diff --git a/Codec/Compression/GZip.hs b/Codec/Compression/GZip.hs --- a/Codec/Compression/GZip.hs +++ b/Codec/Compression/GZip.hs @@ -4,7 +4,7 @@ -- License : BSD-style -- -- Maintainer : duncan.coutts@worc.ox.ac.uk --- Stability : experimental +-- Stability : provisional -- Portability : portable (H98 + FFI) -- -- Compression and decompression of data streams in the gzip format. @@ -37,10 +37,10 @@ compress, compressWith, CompressionLevel(..), - + -- * Decompression decompress - + ) where import Data.ByteString.Lazy (ByteString) diff --git a/Codec/Compression/Zlib.hs b/Codec/Compression/Zlib.hs --- a/Codec/Compression/Zlib.hs +++ b/Codec/Compression/Zlib.hs @@ -4,7 +4,7 @@ -- License : BSD-style -- -- Maintainer : duncan.coutts@worc.ox.ac.uk --- Stability : experimental +-- Stability : provisional -- Portability : portable (H98 + FFI) -- -- Compression and decompression of data streams in the zlib format. @@ -24,7 +24,7 @@ -- * Decompression decompress - + ) where import Data.ByteString.Lazy (ByteString) diff --git a/Codec/Compression/Zlib/Internal.hs b/Codec/Compression/Zlib/Internal.hs --- a/Codec/Compression/Zlib/Internal.hs +++ b/Codec/Compression/Zlib/Internal.hs @@ -1,10 +1,10 @@ ----------------------------------------------------------------------------- -- | --- Copyright : (c) 2006 Duncan Coutts +-- Copyright : (c) 2006-2007 Duncan Coutts -- License : BSD-style -- -- Maintainer : duncan.coutts@worc.ox.ac.uk --- Stability : experimental +-- Stability : provisional -- Portability : portable (H98 + FFI) -- -- Pure stream based interface to lower level zlib wrapper @@ -29,12 +29,15 @@ ) where import Prelude hiding (length) -import Control.Monad (liftM, when) +import Control.Monad (when) import Control.Exception (assert) -import qualified Data.ByteString.Lazy as Lazy -import qualified Data.ByteString as Strict -import qualified Data.ByteString.Base as Base -import Data.ByteString.Base (LazyByteString(LPS)) +import qualified Data.ByteString.Lazy as L +#ifdef BYTESTRING_IN_BASE +import qualified Data.ByteString.Base as S +#else +import qualified Data.ByteString.Lazy.Internal as L +import qualified Data.ByteString.Internal as S +#endif import qualified Codec.Compression.Zlib.Stream as Stream import Codec.Compression.Zlib.Stream (Stream) @@ -42,8 +45,8 @@ compressDefault :: Stream.Format -> Stream.CompressionLevel - -> Lazy.ByteString - -> Lazy.ByteString + -> L.ByteString + -> L.ByteString compressDefault format compressionLevel = compressFull format compressionLevel @@ -54,8 +57,8 @@ decompressDefault :: Stream.Format - -> Lazy.ByteString - -> Lazy.ByteString + -> L.ByteString + -> L.ByteString decompressDefault format = decompressFull format Stream.DefaultWindowBits @@ -68,20 +71,24 @@ -> Stream.WindowBits -> Stream.MemoryLevel -> Stream.CompressionStrategy - -> Lazy.ByteString - -> Lazy.ByteString -compressFull format compLevel method bits memLevel strategy (LPS chunks) = - Stream.run $ do + -> L.ByteString + -> L.ByteString +compressFull format compLevel method bits memLevel strategy input = + L.fromChunks $ Stream.run $ do Stream.deflateInit format compLevel method bits memLevel strategy - case chunks of - [] -> liftM LPS (fillBuffers []) - (Base.PS inFPtr offset length : chunks') -> do + case L.toChunks input of + [] -> fillBuffers [] + S.PS inFPtr offset length : chunks -> do Stream.pushInputBuffer inFPtr offset length - liftM LPS (fillBuffers chunks') + fillBuffers chunks where outChunkSize :: Int +#ifdef BYTESTRING_IN_BASE outChunkSize = 16 * 1024 - 16 +#else + outChunkSize = 16 * 1024 - L.chunkOverhead +#endif -- we flick between two states: -- * where one or other buffer is empty @@ -90,8 +97,8 @@ -- - in which case we compress until a buffer is empty fillBuffers :: - [Strict.ByteString] - -> Stream [Strict.ByteString] + [S.ByteString] + -> Stream [S.ByteString] fillBuffers inChunks = do Stream.consistencyCheck @@ -106,21 +113,21 @@ assert (inputBufferEmpty || outputBufferFull) $ return () when outputBufferFull $ do - outFPtr <- Stream.unsafeLiftIO (Base.mallocByteString outChunkSize) + outFPtr <- Stream.unsafeLiftIO (S.mallocByteString outChunkSize) Stream.pushOutputBuffer outFPtr 0 outChunkSize if inputBufferEmpty then case inChunks of [] -> drainBuffers [] - (Base.PS inFPtr offset length : inChunks') -> do + S.PS inFPtr offset length : inChunks' -> do Stream.pushInputBuffer inFPtr offset length drainBuffers inChunks' else drainBuffers inChunks drainBuffers :: - [Strict.ByteString] - -> Stream [Strict.ByteString] + [S.ByteString] + -> Stream [S.ByteString] drainBuffers inChunks = do inputBufferEmpty' <- Stream.inputBufferEmpty @@ -139,7 +146,7 @@ if outputBufferFull then do (outFPtr, offset, length) <- Stream.popOutputBuffer outChunks <- Stream.unsafeInterleave (fillBuffers inChunks) - return (Base.PS outFPtr offset length : outChunks) + return (S.PS outFPtr offset length : outChunks) else do fillBuffers inChunks Stream.StreamEnd -> do @@ -149,7 +156,7 @@ if outputBufferBytesAvailable > 0 then do (outFPtr, offset, length) <- Stream.popOutputBuffer Stream.finalise - return (Base.PS outFPtr offset length : []) + return [S.PS outFPtr offset length] else do Stream.finalise return [] Stream.BufferError -> fail "BufferError should be impossible!" @@ -160,20 +167,24 @@ decompressFull :: Stream.Format -> Stream.WindowBits - -> Lazy.ByteString - -> Lazy.ByteString -decompressFull format bits (LPS chunks) = - Stream.run $ do + -> L.ByteString + -> L.ByteString +decompressFull format bits input = + L.fromChunks $ Stream.run $ do Stream.inflateInit format bits - case chunks of - [] -> liftM LPS (fillBuffers []) - (Base.PS inFPtr offset length : chunks') -> do + case L.toChunks input of + [] -> fillBuffers [] + S.PS inFPtr offset length : chunks -> do Stream.pushInputBuffer inFPtr offset length - liftM LPS (fillBuffers chunks') + fillBuffers chunks where outChunkSize :: Int +#ifdef BYTESTRING_IN_BASE outChunkSize = 32 * 1024 - 16 +#else + outChunkSize = 32 * 1024 - L.chunkOverhead +#endif -- we flick between two states: -- * where one or other buffer is empty @@ -182,8 +193,8 @@ -- - in which case we compress until a buffer is empty fillBuffers :: - [Strict.ByteString] - -> Stream [Strict.ByteString] + [S.ByteString] + -> Stream [S.ByteString] fillBuffers inChunks = do -- in this state there are two possabilities: @@ -197,21 +208,21 @@ assert (inputBufferEmpty || outputBufferFull) $ return () when outputBufferFull $ do - outFPtr <- Stream.unsafeLiftIO (Base.mallocByteString outChunkSize) + outFPtr <- Stream.unsafeLiftIO (S.mallocByteString outChunkSize) Stream.pushOutputBuffer outFPtr 0 outChunkSize if inputBufferEmpty then case inChunks of [] -> drainBuffers [] - (Base.PS inFPtr offset length : inChunks') -> do + S.PS inFPtr offset length : inChunks' -> do Stream.pushInputBuffer inFPtr offset length drainBuffers inChunks' else drainBuffers inChunks drainBuffers :: - [Strict.ByteString] - -> Stream [Strict.ByteString] + [S.ByteString] + -> Stream [S.ByteString] drainBuffers inChunks = do inputBufferEmpty' <- Stream.inputBufferEmpty @@ -229,7 +240,7 @@ if outputBufferFull then do (outFPtr, offset, length) <- Stream.popOutputBuffer outChunks <- Stream.unsafeInterleave (fillBuffers inChunks) - return (Base.PS outFPtr offset length : outChunks) + return (S.PS outFPtr offset length : outChunks) else do fillBuffers inChunks Stream.StreamEnd -> do @@ -240,7 +251,7 @@ if outputBufferBytesAvailable > 0 then do (outFPtr, offset, length) <- Stream.popOutputBuffer Stream.finalise - return (Base.PS outFPtr offset length : []) + return [S.PS outFPtr offset length] else do Stream.finalise return [] Stream.BufferError -> fail "premature end of compressed stream" diff --git a/Codec/Compression/Zlib/Stream.hsc b/Codec/Compression/Zlib/Stream.hsc --- a/Codec/Compression/Zlib/Stream.hsc +++ b/Codec/Compression/Zlib/Stream.hsc @@ -58,7 +58,11 @@ import Foreign import Foreign.C +#ifdef BYTESTRING_IN_BASE import Data.ByteString.Base +#else +import Data.ByteString.Internal +#endif import System.IO.Unsafe (unsafeInterleaveIO) import System.IO (hPutStrLn, stderr) import Control.Monad (liftM) @@ -66,7 +70,7 @@ import Prelude hiding (length) -#include +#include "zlib.h" pushInputBuffer :: ForeignPtr Word8 -> Int -> Int -> Stream () @@ -387,14 +391,14 @@ | SyncFlush | FullFlush | Finish - | Block +-- | Block -- only available in zlib 1.2 and later, uncomment if you need it. instance Enum Flush where fromEnum NoFlush = #{const Z_NO_FLUSH} fromEnum SyncFlush = #{const Z_SYNC_FLUSH} fromEnum FullFlush = #{const Z_FULL_FLUSH} fromEnum Finish = #{const Z_FINISH} - fromEnum Block = #{const Z_BLOCK} +-- fromEnum Block = #{const Z_BLOCK} data Format = GZip -- ^ Encode or decode with the gzip header format. @@ -480,19 +484,23 @@ -- 'HuffmanOnly'. | HuffmanOnly -- ^ Use 'HuffmanOnly' to force Huffman encoding only (no -- string match). + +{- +-- -- only available in zlib 1.2 and later, uncomment if you need it. | RLE -- ^ Use 'RLE' to limit match distances to one (run-length -- encoding). 'RLE' is designed to be almost as fast as -- 'HuffmanOnly', but give better compression for PNG -- image data. | Fixed -- ^ 'Fixed' prevents the use of dynamic Huffman codes, -- allowing for a simpler decoder for special applications. +-} instance Enum CompressionStrategy where fromEnum DefaultStrategy = #{const Z_DEFAULT_STRATEGY} fromEnum Filtered = #{const Z_FILTERED} fromEnum HuffmanOnly = #{const Z_HUFFMAN_ONLY} - fromEnum RLE = #{const Z_RLE} - fromEnum Fixed = #{const Z_FIXED} +-- fromEnum RLE = #{const Z_RLE} +-- fromEnum Fixed = #{const Z_FIXED} withStreamPtr :: (Ptr StreamState -> IO a) -> Stream a withStreamPtr f = do diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,23 @@ +Copyright (c) 2006-2007, Duncan Coutts +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + +1. Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. +2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +POSSIBILITY OF SUCH DAMAGE. diff --git a/cbits/adler32.c b/cbits/adler32.c new file mode 100644 --- /dev/null +++ b/cbits/adler32.c @@ -0,0 +1,149 @@ +/* adler32.c -- compute the Adler-32 checksum of a data stream + * Copyright (C) 1995-2004 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id$ */ + +#define ZLIB_INTERNAL +#include "zlib.h" + +#define BASE 65521UL /* largest prime smaller than 65536 */ +#define NMAX 5552 +/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ + +#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;} +#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); +#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); +#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); +#define DO16(buf) DO8(buf,0); DO8(buf,8); + +/* use NO_DIVIDE if your processor does not do division in hardware */ +#ifdef NO_DIVIDE +# define MOD(a) \ + do { \ + if (a >= (BASE << 16)) a -= (BASE << 16); \ + if (a >= (BASE << 15)) a -= (BASE << 15); \ + if (a >= (BASE << 14)) a -= (BASE << 14); \ + if (a >= (BASE << 13)) a -= (BASE << 13); \ + if (a >= (BASE << 12)) a -= (BASE << 12); \ + if (a >= (BASE << 11)) a -= (BASE << 11); \ + if (a >= (BASE << 10)) a -= (BASE << 10); \ + if (a >= (BASE << 9)) a -= (BASE << 9); \ + if (a >= (BASE << 8)) a -= (BASE << 8); \ + if (a >= (BASE << 7)) a -= (BASE << 7); \ + if (a >= (BASE << 6)) a -= (BASE << 6); \ + if (a >= (BASE << 5)) a -= (BASE << 5); \ + if (a >= (BASE << 4)) a -= (BASE << 4); \ + if (a >= (BASE << 3)) a -= (BASE << 3); \ + if (a >= (BASE << 2)) a -= (BASE << 2); \ + if (a >= (BASE << 1)) a -= (BASE << 1); \ + if (a >= BASE) a -= BASE; \ + } while (0) +# define MOD4(a) \ + do { \ + if (a >= (BASE << 4)) a -= (BASE << 4); \ + if (a >= (BASE << 3)) a -= (BASE << 3); \ + if (a >= (BASE << 2)) a -= (BASE << 2); \ + if (a >= (BASE << 1)) a -= (BASE << 1); \ + if (a >= BASE) a -= BASE; \ + } while (0) +#else +# define MOD(a) a %= BASE +# define MOD4(a) a %= BASE +#endif + +/* ========================================================================= */ +uLong ZEXPORT adler32(adler, buf, len) + uLong adler; + const Bytef *buf; + uInt len; +{ + unsigned long sum2; + unsigned n; + + /* split Adler-32 into component sums */ + sum2 = (adler >> 16) & 0xffff; + adler &= 0xffff; + + /* in case user likes doing a byte at a time, keep it fast */ + if (len == 1) { + adler += buf[0]; + if (adler >= BASE) + adler -= BASE; + sum2 += adler; + if (sum2 >= BASE) + sum2 -= BASE; + return adler | (sum2 << 16); + } + + /* initial Adler-32 value (deferred check for len == 1 speed) */ + if (buf == Z_NULL) + return 1L; + + /* in case short lengths are provided, keep it somewhat fast */ + if (len < 16) { + while (len--) { + adler += *buf++; + sum2 += adler; + } + if (adler >= BASE) + adler -= BASE; + MOD4(sum2); /* only added so many BASE's */ + return adler | (sum2 << 16); + } + + /* do length NMAX blocks -- requires just one modulo operation */ + while (len >= NMAX) { + len -= NMAX; + n = NMAX / 16; /* NMAX is divisible by 16 */ + do { + DO16(buf); /* 16 sums unrolled */ + buf += 16; + } while (--n); + MOD(adler); + MOD(sum2); + } + + /* do remaining bytes (less than NMAX, still just one modulo) */ + if (len) { /* avoid modulos if none remaining */ + while (len >= 16) { + len -= 16; + DO16(buf); + buf += 16; + } + while (len--) { + adler += *buf++; + sum2 += adler; + } + MOD(adler); + MOD(sum2); + } + + /* return recombined sums */ + return adler | (sum2 << 16); +} + +/* ========================================================================= */ +uLong ZEXPORT adler32_combine(adler1, adler2, len2) + uLong adler1; + uLong adler2; + z_off_t len2; +{ + unsigned long sum1; + unsigned long sum2; + unsigned rem; + + /* the derivation of this formula is left as an exercise for the reader */ + rem = (unsigned)(len2 % BASE); + sum1 = adler1 & 0xffff; + sum2 = rem * sum1; + MOD(sum2); + sum1 += (adler2 & 0xffff) + BASE - 1; + sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem; + if (sum1 > BASE) sum1 -= BASE; + if (sum1 > BASE) sum1 -= BASE; + if (sum2 > (BASE << 1)) sum2 -= (BASE << 1); + if (sum2 > BASE) sum2 -= BASE; + return sum1 | (sum2 << 16); +} diff --git a/cbits/compress.c b/cbits/compress.c new file mode 100644 --- /dev/null +++ b/cbits/compress.c @@ -0,0 +1,79 @@ +/* compress.c -- compress a memory buffer + * Copyright (C) 1995-2003 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id$ */ + +#define ZLIB_INTERNAL +#include "zlib.h" + +/* =========================================================================== + Compresses the source buffer into the destination buffer. The level + parameter has the same meaning as in deflateInit. sourceLen is the byte + length of the source buffer. Upon entry, destLen is the total size of the + destination buffer, which must be at least 0.1% larger than sourceLen plus + 12 bytes. Upon exit, destLen is the actual size of the compressed buffer. + + compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_BUF_ERROR if there was not enough room in the output buffer, + Z_STREAM_ERROR if the level parameter is invalid. +*/ +int ZEXPORT compress2 (dest, destLen, source, sourceLen, level) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; + int level; +{ + z_stream stream; + int err; + + stream.next_in = (Bytef*)source; + stream.avail_in = (uInt)sourceLen; +#ifdef MAXSEG_64K + /* Check for source > 64K on 16-bit machine: */ + if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR; +#endif + stream.next_out = dest; + stream.avail_out = (uInt)*destLen; + if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR; + + stream.zalloc = (alloc_func)0; + stream.zfree = (free_func)0; + stream.opaque = (voidpf)0; + + err = deflateInit(&stream, level); + if (err != Z_OK) return err; + + err = deflate(&stream, Z_FINISH); + if (err != Z_STREAM_END) { + deflateEnd(&stream); + return err == Z_OK ? Z_BUF_ERROR : err; + } + *destLen = stream.total_out; + + err = deflateEnd(&stream); + return err; +} + +/* =========================================================================== + */ +int ZEXPORT compress (dest, destLen, source, sourceLen) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; +{ + return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION); +} + +/* =========================================================================== + If the default memLevel or windowBits for deflateInit() is changed, then + this function needs to be updated. + */ +uLong ZEXPORT compressBound (sourceLen) + uLong sourceLen; +{ + return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11; +} diff --git a/cbits/crc32.c b/cbits/crc32.c new file mode 100644 --- /dev/null +++ b/cbits/crc32.c @@ -0,0 +1,423 @@ +/* crc32.c -- compute the CRC-32 of a data stream + * Copyright (C) 1995-2005 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + * + * Thanks to Rodney Brown for his contribution of faster + * CRC methods: exclusive-oring 32 bits of data at a time, and pre-computing + * tables for updating the shift register in one step with three exclusive-ors + * instead of four steps with four exclusive-ors. This results in about a + * factor of two increase in speed on a Power PC G4 (PPC7455) using gcc -O3. + */ + +/* @(#) $Id$ */ + +/* + Note on the use of DYNAMIC_CRC_TABLE: there is no mutex or semaphore + protection on the static variables used to control the first-use generation + of the crc tables. Therefore, if you #define DYNAMIC_CRC_TABLE, you should + first call get_crc_table() to initialize the tables before allowing more than + one thread to use crc32(). + */ + +#ifdef MAKECRCH +# include +# ifndef DYNAMIC_CRC_TABLE +# define DYNAMIC_CRC_TABLE +# endif /* !DYNAMIC_CRC_TABLE */ +#endif /* MAKECRCH */ + +#include "zutil.h" /* for STDC and FAR definitions */ + +#define local static + +/* Find a four-byte integer type for crc32_little() and crc32_big(). */ +#ifndef NOBYFOUR +# ifdef STDC /* need ANSI C limits.h to determine sizes */ +# include +# define BYFOUR +# if (UINT_MAX == 0xffffffffUL) + typedef unsigned int u4; +# else +# if (ULONG_MAX == 0xffffffffUL) + typedef unsigned long u4; +# else +# if (USHRT_MAX == 0xffffffffUL) + typedef unsigned short u4; +# else +# undef BYFOUR /* can't find a four-byte integer type! */ +# endif +# endif +# endif +# endif /* STDC */ +#endif /* !NOBYFOUR */ + +/* Definitions for doing the crc four data bytes at a time. */ +#ifdef BYFOUR +# define REV(w) (((w)>>24)+(((w)>>8)&0xff00)+ \ + (((w)&0xff00)<<8)+(((w)&0xff)<<24)) + local unsigned long crc32_little OF((unsigned long, + const unsigned char FAR *, unsigned)); + local unsigned long crc32_big OF((unsigned long, + const unsigned char FAR *, unsigned)); +# define TBLS 8 +#else +# define TBLS 1 +#endif /* BYFOUR */ + +/* Local functions for crc concatenation */ +local unsigned long gf2_matrix_times OF((unsigned long *mat, + unsigned long vec)); +local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat)); + +#ifdef DYNAMIC_CRC_TABLE + +local volatile int crc_table_empty = 1; +local unsigned long FAR crc_table[TBLS][256]; +local void make_crc_table OF((void)); +#ifdef MAKECRCH + local void write_table OF((FILE *, const unsigned long FAR *)); +#endif /* MAKECRCH */ +/* + Generate tables for a byte-wise 32-bit CRC calculation on the polynomial: + x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1. + + Polynomials over GF(2) are represented in binary, one bit per coefficient, + with the lowest powers in the most significant bit. Then adding polynomials + is just exclusive-or, and multiplying a polynomial by x is a right shift by + one. If we call the above polynomial p, and represent a byte as the + polynomial q, also with the lowest power in the most significant bit (so the + byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p, + where a mod b means the remainder after dividing a by b. + + This calculation is done using the shift-register method of multiplying and + taking the remainder. The register is initialized to zero, and for each + incoming bit, x^32 is added mod p to the register if the bit is a one (where + x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by + x (which is shifting right by one and adding x^32 mod p if the bit shifted + out is a one). We start with the highest power (least significant bit) of + q and repeat for all eight bits of q. + + The first table is simply the CRC of all possible eight bit values. This is + all the information needed to generate CRCs on data a byte at a time for all + combinations of CRC register values and incoming bytes. The remaining tables + allow for word-at-a-time CRC calculation for both big-endian and little- + endian machines, where a word is four bytes. +*/ +local void make_crc_table() +{ + unsigned long c; + int n, k; + unsigned long poly; /* polynomial exclusive-or pattern */ + /* terms of polynomial defining this crc (except x^32): */ + static volatile int first = 1; /* flag to limit concurrent making */ + static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26}; + + /* See if another task is already doing this (not thread-safe, but better + than nothing -- significantly reduces duration of vulnerability in + case the advice about DYNAMIC_CRC_TABLE is ignored) */ + if (first) { + first = 0; + + /* make exclusive-or pattern from polynomial (0xedb88320UL) */ + poly = 0UL; + for (n = 0; n < sizeof(p)/sizeof(unsigned char); n++) + poly |= 1UL << (31 - p[n]); + + /* generate a crc for every 8-bit value */ + for (n = 0; n < 256; n++) { + c = (unsigned long)n; + for (k = 0; k < 8; k++) + c = c & 1 ? poly ^ (c >> 1) : c >> 1; + crc_table[0][n] = c; + } + +#ifdef BYFOUR + /* generate crc for each value followed by one, two, and three zeros, + and then the byte reversal of those as well as the first table */ + for (n = 0; n < 256; n++) { + c = crc_table[0][n]; + crc_table[4][n] = REV(c); + for (k = 1; k < 4; k++) { + c = crc_table[0][c & 0xff] ^ (c >> 8); + crc_table[k][n] = c; + crc_table[k + 4][n] = REV(c); + } + } +#endif /* BYFOUR */ + + crc_table_empty = 0; + } + else { /* not first */ + /* wait for the other guy to finish (not efficient, but rare) */ + while (crc_table_empty) + ; + } + +#ifdef MAKECRCH + /* write out CRC tables to crc32.h */ + { + FILE *out; + + out = fopen("crc32.h", "w"); + if (out == NULL) return; + fprintf(out, "/* crc32.h -- tables for rapid CRC calculation\n"); + fprintf(out, " * Generated automatically by crc32.c\n */\n\n"); + fprintf(out, "local const unsigned long FAR "); + fprintf(out, "crc_table[TBLS][256] =\n{\n {\n"); + write_table(out, crc_table[0]); +# ifdef BYFOUR + fprintf(out, "#ifdef BYFOUR\n"); + for (k = 1; k < 8; k++) { + fprintf(out, " },\n {\n"); + write_table(out, crc_table[k]); + } + fprintf(out, "#endif\n"); +# endif /* BYFOUR */ + fprintf(out, " }\n};\n"); + fclose(out); + } +#endif /* MAKECRCH */ +} + +#ifdef MAKECRCH +local void write_table(out, table) + FILE *out; + const unsigned long FAR *table; +{ + int n; + + for (n = 0; n < 256; n++) + fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : " ", table[n], + n == 255 ? "\n" : (n % 5 == 4 ? ",\n" : ", ")); +} +#endif /* MAKECRCH */ + +#else /* !DYNAMIC_CRC_TABLE */ +/* ======================================================================== + * Tables of CRC-32s of all single-byte values, made by make_crc_table(). + */ +#include "crc32.h" +#endif /* DYNAMIC_CRC_TABLE */ + +/* ========================================================================= + * This function can be used by asm versions of crc32() + */ +const unsigned long FAR * ZEXPORT get_crc_table() +{ +#ifdef DYNAMIC_CRC_TABLE + if (crc_table_empty) + make_crc_table(); +#endif /* DYNAMIC_CRC_TABLE */ + return (const unsigned long FAR *)crc_table; +} + +/* ========================================================================= */ +#define DO1 crc = crc_table[0][((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8) +#define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1 + +/* ========================================================================= */ +unsigned long ZEXPORT crc32(crc, buf, len) + unsigned long crc; + const unsigned char FAR *buf; + unsigned len; +{ + if (buf == Z_NULL) return 0UL; + +#ifdef DYNAMIC_CRC_TABLE + if (crc_table_empty) + make_crc_table(); +#endif /* DYNAMIC_CRC_TABLE */ + +#ifdef BYFOUR + if (sizeof(void *) == sizeof(ptrdiff_t)) { + u4 endian; + + endian = 1; + if (*((unsigned char *)(&endian))) + return crc32_little(crc, buf, len); + else + return crc32_big(crc, buf, len); + } +#endif /* BYFOUR */ + crc = crc ^ 0xffffffffUL; + while (len >= 8) { + DO8; + len -= 8; + } + if (len) do { + DO1; + } while (--len); + return crc ^ 0xffffffffUL; +} + +#ifdef BYFOUR + +/* ========================================================================= */ +#define DOLIT4 c ^= *buf4++; \ + c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \ + crc_table[1][(c >> 16) & 0xff] ^ crc_table[0][c >> 24] +#define DOLIT32 DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4 + +/* ========================================================================= */ +local unsigned long crc32_little(crc, buf, len) + unsigned long crc; + const unsigned char FAR *buf; + unsigned len; +{ + register u4 c; + register const u4 FAR *buf4; + + c = (u4)crc; + c = ~c; + while (len && ((ptrdiff_t)buf & 3)) { + c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); + len--; + } + + buf4 = (const u4 FAR *)(const void FAR *)buf; + while (len >= 32) { + DOLIT32; + len -= 32; + } + while (len >= 4) { + DOLIT4; + len -= 4; + } + buf = (const unsigned char FAR *)buf4; + + if (len) do { + c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); + } while (--len); + c = ~c; + return (unsigned long)c; +} + +/* ========================================================================= */ +#define DOBIG4 c ^= *++buf4; \ + c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \ + crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24] +#define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4 + +/* ========================================================================= */ +local unsigned long crc32_big(crc, buf, len) + unsigned long crc; + const unsigned char FAR *buf; + unsigned len; +{ + register u4 c; + register const u4 FAR *buf4; + + c = REV((u4)crc); + c = ~c; + while (len && ((ptrdiff_t)buf & 3)) { + c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); + len--; + } + + buf4 = (const u4 FAR *)(const void FAR *)buf; + buf4--; + while (len >= 32) { + DOBIG32; + len -= 32; + } + while (len >= 4) { + DOBIG4; + len -= 4; + } + buf4++; + buf = (const unsigned char FAR *)buf4; + + if (len) do { + c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); + } while (--len); + c = ~c; + return (unsigned long)(REV(c)); +} + +#endif /* BYFOUR */ + +#define GF2_DIM 32 /* dimension of GF(2) vectors (length of CRC) */ + +/* ========================================================================= */ +local unsigned long gf2_matrix_times(mat, vec) + unsigned long *mat; + unsigned long vec; +{ + unsigned long sum; + + sum = 0; + while (vec) { + if (vec & 1) + sum ^= *mat; + vec >>= 1; + mat++; + } + return sum; +} + +/* ========================================================================= */ +local void gf2_matrix_square(square, mat) + unsigned long *square; + unsigned long *mat; +{ + int n; + + for (n = 0; n < GF2_DIM; n++) + square[n] = gf2_matrix_times(mat, mat[n]); +} + +/* ========================================================================= */ +uLong ZEXPORT crc32_combine(crc1, crc2, len2) + uLong crc1; + uLong crc2; + z_off_t len2; +{ + int n; + unsigned long row; + unsigned long even[GF2_DIM]; /* even-power-of-two zeros operator */ + unsigned long odd[GF2_DIM]; /* odd-power-of-two zeros operator */ + + /* degenerate case */ + if (len2 == 0) + return crc1; + + /* put operator for one zero bit in odd */ + odd[0] = 0xedb88320L; /* CRC-32 polynomial */ + row = 1; + for (n = 1; n < GF2_DIM; n++) { + odd[n] = row; + row <<= 1; + } + + /* put operator for two zero bits in even */ + gf2_matrix_square(even, odd); + + /* put operator for four zero bits in odd */ + gf2_matrix_square(odd, even); + + /* apply len2 zeros to crc1 (first square will put the operator for one + zero byte, eight zero bits, in even) */ + do { + /* apply zeros operator for this bit of len2 */ + gf2_matrix_square(even, odd); + if (len2 & 1) + crc1 = gf2_matrix_times(even, crc1); + len2 >>= 1; + + /* if no more bits set, then done */ + if (len2 == 0) + break; + + /* another iteration of the loop with odd and even swapped */ + gf2_matrix_square(odd, even); + if (len2 & 1) + crc1 = gf2_matrix_times(odd, crc1); + len2 >>= 1; + + /* if no more bits set, then done */ + } while (len2 != 0); + + /* return combined crc */ + crc1 ^= crc2; + return crc1; +} diff --git a/cbits/deflate.c b/cbits/deflate.c new file mode 100644 --- /dev/null +++ b/cbits/deflate.c @@ -0,0 +1,1736 @@ +/* deflate.c -- compress data using the deflation algorithm + * Copyright (C) 1995-2005 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * ALGORITHM + * + * The "deflation" process depends on being able to identify portions + * of the input text which are identical to earlier input (within a + * sliding window trailing behind the input currently being processed). + * + * The most straightforward technique turns out to be the fastest for + * most input files: try all possible matches and select the longest. + * The key feature of this algorithm is that insertions into the string + * dictionary are very simple and thus fast, and deletions are avoided + * completely. Insertions are performed at each input character, whereas + * string matches are performed only when the previous match ends. So it + * is preferable to spend more time in matches to allow very fast string + * insertions and avoid deletions. The matching algorithm for small + * strings is inspired from that of Rabin & Karp. A brute force approach + * is used to find longer strings when a small match has been found. + * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze + * (by Leonid Broukhis). + * A previous version of this file used a more sophisticated algorithm + * (by Fiala and Greene) which is guaranteed to run in linear amortized + * time, but has a larger average cost, uses more memory and is patented. + * However the F&G algorithm may be faster for some highly redundant + * files if the parameter max_chain_length (described below) is too large. + * + * ACKNOWLEDGEMENTS + * + * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and + * I found it in 'freeze' written by Leonid Broukhis. + * Thanks to many people for bug reports and testing. + * + * REFERENCES + * + * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". + * Available in http://www.ietf.org/rfc/rfc1951.txt + * + * A description of the Rabin and Karp algorithm is given in the book + * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. + * + * Fiala,E.R., and Greene,D.H. + * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 + * + */ + +/* @(#) $Id$ */ + +#include "deflate.h" + +const char deflate_copyright[] = + " deflate 1.2.3 Copyright 1995-2005 Jean-loup Gailly "; +/* + If you use the zlib library in a product, an acknowledgment is welcome + in the documentation of your product. If for some reason you cannot + include such an acknowledgment, I would appreciate that you keep this + copyright string in the executable of your product. + */ + +/* =========================================================================== + * Function prototypes. + */ +typedef enum { + need_more, /* block not completed, need more input or more output */ + block_done, /* block flush performed */ + finish_started, /* finish started, need only more output at next deflate */ + finish_done /* finish done, accept no more input or output */ +} block_state; + +typedef block_state (*compress_func) OF((deflate_state *s, int flush)); +/* Compression function. Returns the block state after the call. */ + +local void fill_window OF((deflate_state *s)); +local block_state deflate_stored OF((deflate_state *s, int flush)); +local block_state deflate_fast OF((deflate_state *s, int flush)); +#ifndef FASTEST +local block_state deflate_slow OF((deflate_state *s, int flush)); +#endif +local void lm_init OF((deflate_state *s)); +local void putShortMSB OF((deflate_state *s, uInt b)); +local void flush_pending OF((z_streamp strm)); +local int read_buf OF((z_streamp strm, Bytef *buf, unsigned size)); +#ifndef FASTEST +#ifdef ASMV + void match_init OF((void)); /* asm code initialization */ + uInt longest_match OF((deflate_state *s, IPos cur_match)); +#else +local uInt longest_match OF((deflate_state *s, IPos cur_match)); +#endif +#endif +local uInt longest_match_fast OF((deflate_state *s, IPos cur_match)); + +#ifdef DEBUG +local void check_match OF((deflate_state *s, IPos start, IPos match, + int length)); +#endif + +/* =========================================================================== + * Local data + */ + +#define NIL 0 +/* Tail of hash chains */ + +#ifndef TOO_FAR +# define TOO_FAR 4096 +#endif +/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ + +#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) +/* Minimum amount of lookahead, except at the end of the input file. + * See deflate.c for comments about the MIN_MATCH+1. + */ + +/* Values for max_lazy_match, good_match and max_chain_length, depending on + * the desired pack level (0..9). The values given below have been tuned to + * exclude worst case performance for pathological files. Better values may be + * found for specific files. + */ +typedef struct config_s { + ush good_length; /* reduce lazy search above this match length */ + ush max_lazy; /* do not perform lazy search above this match length */ + ush nice_length; /* quit search above this match length */ + ush max_chain; + compress_func func; +} config; + +#ifdef FASTEST +local const config configuration_table[2] = { +/* good lazy nice chain */ +/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ +/* 1 */ {4, 4, 8, 4, deflate_fast}}; /* max speed, no lazy matches */ +#else +local const config configuration_table[10] = { +/* good lazy nice chain */ +/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ +/* 1 */ {4, 4, 8, 4, deflate_fast}, /* max speed, no lazy matches */ +/* 2 */ {4, 5, 16, 8, deflate_fast}, +/* 3 */ {4, 6, 32, 32, deflate_fast}, + +/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ +/* 5 */ {8, 16, 32, 32, deflate_slow}, +/* 6 */ {8, 16, 128, 128, deflate_slow}, +/* 7 */ {8, 32, 128, 256, deflate_slow}, +/* 8 */ {32, 128, 258, 1024, deflate_slow}, +/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* max compression */ +#endif + +/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 + * For deflate_fast() (levels <= 3) good is ignored and lazy has a different + * meaning. + */ + +#define EQUAL 0 +/* result of memcmp for equal strings */ + +#ifndef NO_DUMMY_DECL +struct static_tree_desc_s {int dummy;}; /* for buggy compilers */ +#endif + +/* =========================================================================== + * Update a hash value with the given input byte + * IN assertion: all calls to to UPDATE_HASH are made with consecutive + * input characters, so that a running hash key can be computed from the + * previous key instead of complete recalculation each time. + */ +#define UPDATE_HASH(s,h,c) (h = (((h)<hash_shift) ^ (c)) & s->hash_mask) + + +/* =========================================================================== + * Insert string str in the dictionary and set match_head to the previous head + * of the hash chain (the most recent string with same hash key). Return + * the previous length of the hash chain. + * If this file is compiled with -DFASTEST, the compression level is forced + * to 1, and no hash chains are maintained. + * IN assertion: all calls to to INSERT_STRING are made with consecutive + * input characters and the first MIN_MATCH bytes of str are valid + * (except for the last MIN_MATCH-1 bytes of the input file). + */ +#ifdef FASTEST +#define INSERT_STRING(s, str, match_head) \ + (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ + match_head = s->head[s->ins_h], \ + s->head[s->ins_h] = (Pos)(str)) +#else +#define INSERT_STRING(s, str, match_head) \ + (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ + match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \ + s->head[s->ins_h] = (Pos)(str)) +#endif + +/* =========================================================================== + * Initialize the hash table (avoiding 64K overflow for 16 bit systems). + * prev[] will be initialized on the fly. + */ +#define CLEAR_HASH(s) \ + s->head[s->hash_size-1] = NIL; \ + zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); + +/* ========================================================================= */ +int ZEXPORT deflateInit_(strm, level, version, stream_size) + z_streamp strm; + int level; + const char *version; + int stream_size; +{ + return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, + Z_DEFAULT_STRATEGY, version, stream_size); + /* To do: ignore strm->next_in if we use it as window */ +} + +/* ========================================================================= */ +int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy, + version, stream_size) + z_streamp strm; + int level; + int method; + int windowBits; + int memLevel; + int strategy; + const char *version; + int stream_size; +{ + deflate_state *s; + int wrap = 1; + static const char my_version[] = ZLIB_VERSION; + + ushf *overlay; + /* We overlay pending_buf and d_buf+l_buf. This works since the average + * output size for (length,distance) codes is <= 24 bits. + */ + + if (version == Z_NULL || version[0] != my_version[0] || + stream_size != sizeof(z_stream)) { + return Z_VERSION_ERROR; + } + if (strm == Z_NULL) return Z_STREAM_ERROR; + + strm->msg = Z_NULL; + if (strm->zalloc == (alloc_func)0) { + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; + } + if (strm->zfree == (free_func)0) strm->zfree = zcfree; + +#ifdef FASTEST + if (level != 0) level = 1; +#else + if (level == Z_DEFAULT_COMPRESSION) level = 6; +#endif + + if (windowBits < 0) { /* suppress zlib wrapper */ + wrap = 0; + windowBits = -windowBits; + } +#ifdef GZIP + else if (windowBits > 15) { + wrap = 2; /* write gzip wrapper instead */ + windowBits -= 16; + } +#endif + if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || + windowBits < 8 || windowBits > 15 || level < 0 || level > 9 || + strategy < 0 || strategy > Z_FIXED) { + return Z_STREAM_ERROR; + } + if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */ + s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); + if (s == Z_NULL) return Z_MEM_ERROR; + strm->state = (struct internal_state FAR *)s; + s->strm = strm; + + s->wrap = wrap; + s->gzhead = Z_NULL; + s->w_bits = windowBits; + s->w_size = 1 << s->w_bits; + s->w_mask = s->w_size - 1; + + s->hash_bits = memLevel + 7; + s->hash_size = 1 << s->hash_bits; + s->hash_mask = s->hash_size - 1; + s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); + + s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); + s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); + s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); + + s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ + + overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); + s->pending_buf = (uchf *) overlay; + s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L); + + if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || + s->pending_buf == Z_NULL) { + s->status = FINISH_STATE; + strm->msg = (char*)ERR_MSG(Z_MEM_ERROR); + deflateEnd (strm); + return Z_MEM_ERROR; + } + s->d_buf = overlay + s->lit_bufsize/sizeof(ush); + s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; + + s->level = level; + s->strategy = strategy; + s->method = (Byte)method; + + return deflateReset(strm); +} + +/* ========================================================================= */ +int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength) + z_streamp strm; + const Bytef *dictionary; + uInt dictLength; +{ + deflate_state *s; + uInt length = dictLength; + uInt n; + IPos hash_head = 0; + + if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL || + strm->state->wrap == 2 || + (strm->state->wrap == 1 && strm->state->status != INIT_STATE)) + return Z_STREAM_ERROR; + + s = strm->state; + if (s->wrap) + strm->adler = adler32(strm->adler, dictionary, dictLength); + + if (length < MIN_MATCH) return Z_OK; + if (length > MAX_DIST(s)) { + length = MAX_DIST(s); + dictionary += dictLength - length; /* use the tail of the dictionary */ + } + zmemcpy(s->window, dictionary, length); + s->strstart = length; + s->block_start = (long)length; + + /* Insert all strings in the hash table (except for the last two bytes). + * s->lookahead stays null, so s->ins_h will be recomputed at the next + * call of fill_window. + */ + s->ins_h = s->window[0]; + UPDATE_HASH(s, s->ins_h, s->window[1]); + for (n = 0; n <= length - MIN_MATCH; n++) { + INSERT_STRING(s, n, hash_head); + } + if (hash_head) hash_head = 0; /* to make compiler happy */ + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateReset (strm) + z_streamp strm; +{ + deflate_state *s; + + if (strm == Z_NULL || strm->state == Z_NULL || + strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) { + return Z_STREAM_ERROR; + } + + strm->total_in = strm->total_out = 0; + strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ + strm->data_type = Z_UNKNOWN; + + s = (deflate_state *)strm->state; + s->pending = 0; + s->pending_out = s->pending_buf; + + if (s->wrap < 0) { + s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */ + } + s->status = s->wrap ? INIT_STATE : BUSY_STATE; + strm->adler = +#ifdef GZIP + s->wrap == 2 ? crc32(0L, Z_NULL, 0) : +#endif + adler32(0L, Z_NULL, 0); + s->last_flush = Z_NO_FLUSH; + + _tr_init(s); + lm_init(s); + + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateSetHeader (strm, head) + z_streamp strm; + gz_headerp head; +{ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + if (strm->state->wrap != 2) return Z_STREAM_ERROR; + strm->state->gzhead = head; + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflatePrime (strm, bits, value) + z_streamp strm; + int bits; + int value; +{ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + strm->state->bi_valid = bits; + strm->state->bi_buf = (ush)(value & ((1 << bits) - 1)); + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateParams(strm, level, strategy) + z_streamp strm; + int level; + int strategy; +{ + deflate_state *s; + compress_func func; + int err = Z_OK; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + s = strm->state; + +#ifdef FASTEST + if (level != 0) level = 1; +#else + if (level == Z_DEFAULT_COMPRESSION) level = 6; +#endif + if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) { + return Z_STREAM_ERROR; + } + func = configuration_table[s->level].func; + + if (func != configuration_table[level].func && strm->total_in != 0) { + /* Flush the last buffer: */ + err = deflate(strm, Z_PARTIAL_FLUSH); + } + if (s->level != level) { + s->level = level; + s->max_lazy_match = configuration_table[level].max_lazy; + s->good_match = configuration_table[level].good_length; + s->nice_match = configuration_table[level].nice_length; + s->max_chain_length = configuration_table[level].max_chain; + } + s->strategy = strategy; + return err; +} + +/* ========================================================================= */ +int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain) + z_streamp strm; + int good_length; + int max_lazy; + int nice_length; + int max_chain; +{ + deflate_state *s; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + s = strm->state; + s->good_match = good_length; + s->max_lazy_match = max_lazy; + s->nice_match = nice_length; + s->max_chain_length = max_chain; + return Z_OK; +} + +/* ========================================================================= + * For the default windowBits of 15 and memLevel of 8, this function returns + * a close to exact, as well as small, upper bound on the compressed size. + * They are coded as constants here for a reason--if the #define's are + * changed, then this function needs to be changed as well. The return + * value for 15 and 8 only works for those exact settings. + * + * For any setting other than those defaults for windowBits and memLevel, + * the value returned is a conservative worst case for the maximum expansion + * resulting from using fixed blocks instead of stored blocks, which deflate + * can emit on compressed data for some combinations of the parameters. + * + * This function could be more sophisticated to provide closer upper bounds + * for every combination of windowBits and memLevel, as well as wrap. + * But even the conservative upper bound of about 14% expansion does not + * seem onerous for output buffer allocation. + */ +uLong ZEXPORT deflateBound(strm, sourceLen) + z_streamp strm; + uLong sourceLen; +{ + deflate_state *s; + uLong destLen; + + /* conservative upper bound */ + destLen = sourceLen + + ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 11; + + /* if can't get parameters, return conservative bound */ + if (strm == Z_NULL || strm->state == Z_NULL) + return destLen; + + /* if not default parameters, return conservative bound */ + s = strm->state; + if (s->w_bits != 15 || s->hash_bits != 8 + 7) + return destLen; + + /* default settings: return tight bound for that case */ + return compressBound(sourceLen); +} + +/* ========================================================================= + * Put a short in the pending buffer. The 16-bit value is put in MSB order. + * IN assertion: the stream state is correct and there is enough room in + * pending_buf. + */ +local void putShortMSB (s, b) + deflate_state *s; + uInt b; +{ + put_byte(s, (Byte)(b >> 8)); + put_byte(s, (Byte)(b & 0xff)); +} + +/* ========================================================================= + * Flush as much pending output as possible. All deflate() output goes + * through this function so some applications may wish to modify it + * to avoid allocating a large strm->next_out buffer and copying into it. + * (See also read_buf()). + */ +local void flush_pending(strm) + z_streamp strm; +{ + unsigned len = strm->state->pending; + + if (len > strm->avail_out) len = strm->avail_out; + if (len == 0) return; + + zmemcpy(strm->next_out, strm->state->pending_out, len); + strm->next_out += len; + strm->state->pending_out += len; + strm->total_out += len; + strm->avail_out -= len; + strm->state->pending -= len; + if (strm->state->pending == 0) { + strm->state->pending_out = strm->state->pending_buf; + } +} + +/* ========================================================================= */ +int ZEXPORT deflate (strm, flush) + z_streamp strm; + int flush; +{ + int old_flush; /* value of flush param for previous deflate call */ + deflate_state *s; + + if (strm == Z_NULL || strm->state == Z_NULL || + flush > Z_FINISH || flush < 0) { + return Z_STREAM_ERROR; + } + s = strm->state; + + if (strm->next_out == Z_NULL || + (strm->next_in == Z_NULL && strm->avail_in != 0) || + (s->status == FINISH_STATE && flush != Z_FINISH)) { + ERR_RETURN(strm, Z_STREAM_ERROR); + } + if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); + + s->strm = strm; /* just in case */ + old_flush = s->last_flush; + s->last_flush = flush; + + /* Write the header */ + if (s->status == INIT_STATE) { +#ifdef GZIP + if (s->wrap == 2) { + strm->adler = crc32(0L, Z_NULL, 0); + put_byte(s, 31); + put_byte(s, 139); + put_byte(s, 8); + if (s->gzhead == NULL) { + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, s->level == 9 ? 2 : + (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? + 4 : 0)); + put_byte(s, OS_CODE); + s->status = BUSY_STATE; + } + else { + put_byte(s, (s->gzhead->text ? 1 : 0) + + (s->gzhead->hcrc ? 2 : 0) + + (s->gzhead->extra == Z_NULL ? 0 : 4) + + (s->gzhead->name == Z_NULL ? 0 : 8) + + (s->gzhead->comment == Z_NULL ? 0 : 16) + ); + put_byte(s, (Byte)(s->gzhead->time & 0xff)); + put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff)); + put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff)); + put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff)); + put_byte(s, s->level == 9 ? 2 : + (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? + 4 : 0)); + put_byte(s, s->gzhead->os & 0xff); + if (s->gzhead->extra != NULL) { + put_byte(s, s->gzhead->extra_len & 0xff); + put_byte(s, (s->gzhead->extra_len >> 8) & 0xff); + } + if (s->gzhead->hcrc) + strm->adler = crc32(strm->adler, s->pending_buf, + s->pending); + s->gzindex = 0; + s->status = EXTRA_STATE; + } + } + else +#endif + { + uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; + uInt level_flags; + + if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2) + level_flags = 0; + else if (s->level < 6) + level_flags = 1; + else if (s->level == 6) + level_flags = 2; + else + level_flags = 3; + header |= (level_flags << 6); + if (s->strstart != 0) header |= PRESET_DICT; + header += 31 - (header % 31); + + s->status = BUSY_STATE; + putShortMSB(s, header); + + /* Save the adler32 of the preset dictionary: */ + if (s->strstart != 0) { + putShortMSB(s, (uInt)(strm->adler >> 16)); + putShortMSB(s, (uInt)(strm->adler & 0xffff)); + } + strm->adler = adler32(0L, Z_NULL, 0); + } + } +#ifdef GZIP + if (s->status == EXTRA_STATE) { + if (s->gzhead->extra != NULL) { + uInt beg = s->pending; /* start of bytes to update crc */ + + while (s->gzindex < (s->gzhead->extra_len & 0xffff)) { + if (s->pending == s->pending_buf_size) { + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + flush_pending(strm); + beg = s->pending; + if (s->pending == s->pending_buf_size) + break; + } + put_byte(s, s->gzhead->extra[s->gzindex]); + s->gzindex++; + } + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + if (s->gzindex == s->gzhead->extra_len) { + s->gzindex = 0; + s->status = NAME_STATE; + } + } + else + s->status = NAME_STATE; + } + if (s->status == NAME_STATE) { + if (s->gzhead->name != NULL) { + uInt beg = s->pending; /* start of bytes to update crc */ + int val; + + do { + if (s->pending == s->pending_buf_size) { + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + flush_pending(strm); + beg = s->pending; + if (s->pending == s->pending_buf_size) { + val = 1; + break; + } + } + val = s->gzhead->name[s->gzindex++]; + put_byte(s, val); + } while (val != 0); + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + if (val == 0) { + s->gzindex = 0; + s->status = COMMENT_STATE; + } + } + else + s->status = COMMENT_STATE; + } + if (s->status == COMMENT_STATE) { + if (s->gzhead->comment != NULL) { + uInt beg = s->pending; /* start of bytes to update crc */ + int val; + + do { + if (s->pending == s->pending_buf_size) { + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + flush_pending(strm); + beg = s->pending; + if (s->pending == s->pending_buf_size) { + val = 1; + break; + } + } + val = s->gzhead->comment[s->gzindex++]; + put_byte(s, val); + } while (val != 0); + if (s->gzhead->hcrc && s->pending > beg) + strm->adler = crc32(strm->adler, s->pending_buf + beg, + s->pending - beg); + if (val == 0) + s->status = HCRC_STATE; + } + else + s->status = HCRC_STATE; + } + if (s->status == HCRC_STATE) { + if (s->gzhead->hcrc) { + if (s->pending + 2 > s->pending_buf_size) + flush_pending(strm); + if (s->pending + 2 <= s->pending_buf_size) { + put_byte(s, (Byte)(strm->adler & 0xff)); + put_byte(s, (Byte)((strm->adler >> 8) & 0xff)); + strm->adler = crc32(0L, Z_NULL, 0); + s->status = BUSY_STATE; + } + } + else + s->status = BUSY_STATE; + } +#endif + + /* Flush as much pending output as possible */ + if (s->pending != 0) { + flush_pending(strm); + if (strm->avail_out == 0) { + /* Since avail_out is 0, deflate will be called again with + * more output space, but possibly with both pending and + * avail_in equal to zero. There won't be anything to do, + * but this is not an error situation so make sure we + * return OK instead of BUF_ERROR at next call of deflate: + */ + s->last_flush = -1; + return Z_OK; + } + + /* Make sure there is something to do and avoid duplicate consecutive + * flushes. For repeated and useless calls with Z_FINISH, we keep + * returning Z_STREAM_END instead of Z_BUF_ERROR. + */ + } else if (strm->avail_in == 0 && flush <= old_flush && + flush != Z_FINISH) { + ERR_RETURN(strm, Z_BUF_ERROR); + } + + /* User must not provide more input after the first FINISH: */ + if (s->status == FINISH_STATE && strm->avail_in != 0) { + ERR_RETURN(strm, Z_BUF_ERROR); + } + + /* Start a new block or continue the current one. + */ + if (strm->avail_in != 0 || s->lookahead != 0 || + (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { + block_state bstate; + + bstate = (*(configuration_table[s->level].func))(s, flush); + + if (bstate == finish_started || bstate == finish_done) { + s->status = FINISH_STATE; + } + if (bstate == need_more || bstate == finish_started) { + if (strm->avail_out == 0) { + s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ + } + return Z_OK; + /* If flush != Z_NO_FLUSH && avail_out == 0, the next call + * of deflate should use the same flush parameter to make sure + * that the flush is complete. So we don't have to output an + * empty block here, this will be done at next call. This also + * ensures that for a very small output buffer, we emit at most + * one empty block. + */ + } + if (bstate == block_done) { + if (flush == Z_PARTIAL_FLUSH) { + _tr_align(s); + } else { /* FULL_FLUSH or SYNC_FLUSH */ + _tr_stored_block(s, (char*)0, 0L, 0); + /* For a full flush, this empty block will be recognized + * as a special marker by inflate_sync(). + */ + if (flush == Z_FULL_FLUSH) { + CLEAR_HASH(s); /* forget history */ + } + } + flush_pending(strm); + if (strm->avail_out == 0) { + s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ + return Z_OK; + } + } + } + Assert(strm->avail_out > 0, "bug2"); + + if (flush != Z_FINISH) return Z_OK; + if (s->wrap <= 0) return Z_STREAM_END; + + /* Write the trailer */ +#ifdef GZIP + if (s->wrap == 2) { + put_byte(s, (Byte)(strm->adler & 0xff)); + put_byte(s, (Byte)((strm->adler >> 8) & 0xff)); + put_byte(s, (Byte)((strm->adler >> 16) & 0xff)); + put_byte(s, (Byte)((strm->adler >> 24) & 0xff)); + put_byte(s, (Byte)(strm->total_in & 0xff)); + put_byte(s, (Byte)((strm->total_in >> 8) & 0xff)); + put_byte(s, (Byte)((strm->total_in >> 16) & 0xff)); + put_byte(s, (Byte)((strm->total_in >> 24) & 0xff)); + } + else +#endif + { + putShortMSB(s, (uInt)(strm->adler >> 16)); + putShortMSB(s, (uInt)(strm->adler & 0xffff)); + } + flush_pending(strm); + /* If avail_out is zero, the application will call deflate again + * to flush the rest. + */ + if (s->wrap > 0) s->wrap = -s->wrap; /* write the trailer only once! */ + return s->pending != 0 ? Z_OK : Z_STREAM_END; +} + +/* ========================================================================= */ +int ZEXPORT deflateEnd (strm) + z_streamp strm; +{ + int status; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + + status = strm->state->status; + if (status != INIT_STATE && + status != EXTRA_STATE && + status != NAME_STATE && + status != COMMENT_STATE && + status != HCRC_STATE && + status != BUSY_STATE && + status != FINISH_STATE) { + return Z_STREAM_ERROR; + } + + /* Deallocate in reverse order of allocations: */ + TRY_FREE(strm, strm->state->pending_buf); + TRY_FREE(strm, strm->state->head); + TRY_FREE(strm, strm->state->prev); + TRY_FREE(strm, strm->state->window); + + ZFREE(strm, strm->state); + strm->state = Z_NULL; + + return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; +} + +/* ========================================================================= + * Copy the source state to the destination state. + * To simplify the source, this is not supported for 16-bit MSDOS (which + * doesn't have enough memory anyway to duplicate compression states). + */ +int ZEXPORT deflateCopy (dest, source) + z_streamp dest; + z_streamp source; +{ +#ifdef MAXSEG_64K + return Z_STREAM_ERROR; +#else + deflate_state *ds; + deflate_state *ss; + ushf *overlay; + + + if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) { + return Z_STREAM_ERROR; + } + + ss = source->state; + + zmemcpy(dest, source, sizeof(z_stream)); + + ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); + if (ds == Z_NULL) return Z_MEM_ERROR; + dest->state = (struct internal_state FAR *) ds; + zmemcpy(ds, ss, sizeof(deflate_state)); + ds->strm = dest; + + ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); + ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); + ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); + overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); + ds->pending_buf = (uchf *) overlay; + + if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL || + ds->pending_buf == Z_NULL) { + deflateEnd (dest); + return Z_MEM_ERROR; + } + /* following zmemcpy do not work for 16-bit MSDOS */ + zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); + zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos)); + zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos)); + zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); + + ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); + ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush); + ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; + + ds->l_desc.dyn_tree = ds->dyn_ltree; + ds->d_desc.dyn_tree = ds->dyn_dtree; + ds->bl_desc.dyn_tree = ds->bl_tree; + + return Z_OK; +#endif /* MAXSEG_64K */ +} + +/* =========================================================================== + * Read a new buffer from the current input stream, update the adler32 + * and total number of bytes read. All deflate() input goes through + * this function so some applications may wish to modify it to avoid + * allocating a large strm->next_in buffer and copying from it. + * (See also flush_pending()). + */ +local int read_buf(strm, buf, size) + z_streamp strm; + Bytef *buf; + unsigned size; +{ + unsigned len = strm->avail_in; + + if (len > size) len = size; + if (len == 0) return 0; + + strm->avail_in -= len; + + if (strm->state->wrap == 1) { + strm->adler = adler32(strm->adler, strm->next_in, len); + } +#ifdef GZIP + else if (strm->state->wrap == 2) { + strm->adler = crc32(strm->adler, strm->next_in, len); + } +#endif + zmemcpy(buf, strm->next_in, len); + strm->next_in += len; + strm->total_in += len; + + return (int)len; +} + +/* =========================================================================== + * Initialize the "longest match" routines for a new zlib stream + */ +local void lm_init (s) + deflate_state *s; +{ + s->window_size = (ulg)2L*s->w_size; + + CLEAR_HASH(s); + + /* Set the default configuration parameters: + */ + s->max_lazy_match = configuration_table[s->level].max_lazy; + s->good_match = configuration_table[s->level].good_length; + s->nice_match = configuration_table[s->level].nice_length; + s->max_chain_length = configuration_table[s->level].max_chain; + + s->strstart = 0; + s->block_start = 0L; + s->lookahead = 0; + s->match_length = s->prev_length = MIN_MATCH-1; + s->match_available = 0; + s->ins_h = 0; +#ifndef FASTEST +#ifdef ASMV + match_init(); /* initialize the asm code */ +#endif +#endif +} + +#ifndef FASTEST +/* =========================================================================== + * Set match_start to the longest match starting at the given string and + * return its length. Matches shorter or equal to prev_length are discarded, + * in which case the result is equal to prev_length and match_start is + * garbage. + * IN assertions: cur_match is the head of the hash chain for the current + * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 + * OUT assertion: the match length is not greater than s->lookahead. + */ +#ifndef ASMV +/* For 80x86 and 680x0, an optimized version will be provided in match.asm or + * match.S. The code will be functionally equivalent. + */ +local uInt longest_match(s, cur_match) + deflate_state *s; + IPos cur_match; /* current match */ +{ + unsigned chain_length = s->max_chain_length;/* max hash chain length */ + register Bytef *scan = s->window + s->strstart; /* current string */ + register Bytef *match; /* matched string */ + register int len; /* length of current match */ + int best_len = s->prev_length; /* best match length so far */ + int nice_match = s->nice_match; /* stop if match long enough */ + IPos limit = s->strstart > (IPos)MAX_DIST(s) ? + s->strstart - (IPos)MAX_DIST(s) : NIL; + /* Stop when cur_match becomes <= limit. To simplify the code, + * we prevent matches with the string of window index 0. + */ + Posf *prev = s->prev; + uInt wmask = s->w_mask; + +#ifdef UNALIGNED_OK + /* Compare two bytes at a time. Note: this is not always beneficial. + * Try with and without -DUNALIGNED_OK to check. + */ + register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; + register ush scan_start = *(ushf*)scan; + register ush scan_end = *(ushf*)(scan+best_len-1); +#else + register Bytef *strend = s->window + s->strstart + MAX_MATCH; + register Byte scan_end1 = scan[best_len-1]; + register Byte scan_end = scan[best_len]; +#endif + + /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. + * It is easy to get rid of this optimization if necessary. + */ + Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); + + /* Do not waste too much time if we already have a good match: */ + if (s->prev_length >= s->good_match) { + chain_length >>= 2; + } + /* Do not look for matches beyond the end of the input. This is necessary + * to make deflate deterministic. + */ + if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; + + Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); + + do { + Assert(cur_match < s->strstart, "no future"); + match = s->window + cur_match; + + /* Skip to next match if the match length cannot increase + * or if the match length is less than 2. Note that the checks below + * for insufficient lookahead only occur occasionally for performance + * reasons. Therefore uninitialized memory will be accessed, and + * conditional jumps will be made that depend on those values. + * However the length of the match is limited to the lookahead, so + * the output of deflate is not affected by the uninitialized values. + */ +#if (defined(UNALIGNED_OK) && MAX_MATCH == 258) + /* This code assumes sizeof(unsigned short) == 2. Do not use + * UNALIGNED_OK if your compiler uses a different size. + */ + if (*(ushf*)(match+best_len-1) != scan_end || + *(ushf*)match != scan_start) continue; + + /* It is not necessary to compare scan[2] and match[2] since they are + * always equal when the other bytes match, given that the hash keys + * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at + * strstart+3, +5, ... up to strstart+257. We check for insufficient + * lookahead only every 4th comparison; the 128th check will be made + * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is + * necessary to put more guard bytes at the end of the window, or + * to check more often for insufficient lookahead. + */ + Assert(scan[2] == match[2], "scan[2]?"); + scan++, match++; + do { + } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + scan < strend); + /* The funny "do {}" generates better code on most compilers */ + + /* Here, scan <= window+strstart+257 */ + Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + if (*scan == *match) scan++; + + len = (MAX_MATCH - 1) - (int)(strend-scan); + scan = strend - (MAX_MATCH-1); + +#else /* UNALIGNED_OK */ + + if (match[best_len] != scan_end || + match[best_len-1] != scan_end1 || + *match != *scan || + *++match != scan[1]) continue; + + /* The check at best_len-1 can be removed because it will be made + * again later. (This heuristic is not always a win.) + * It is not necessary to compare scan[2] and match[2] since they + * are always equal when the other bytes match, given that + * the hash keys are equal and that HASH_BITS >= 8. + */ + scan += 2, match++; + Assert(*scan == *match, "match[2]?"); + + /* We check for insufficient lookahead only every 8th comparison; + * the 256th check will be made at strstart+258. + */ + do { + } while (*++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + scan < strend); + + Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + + len = MAX_MATCH - (int)(strend - scan); + scan = strend - MAX_MATCH; + +#endif /* UNALIGNED_OK */ + + if (len > best_len) { + s->match_start = cur_match; + best_len = len; + if (len >= nice_match) break; +#ifdef UNALIGNED_OK + scan_end = *(ushf*)(scan+best_len-1); +#else + scan_end1 = scan[best_len-1]; + scan_end = scan[best_len]; +#endif + } + } while ((cur_match = prev[cur_match & wmask]) > limit + && --chain_length != 0); + + if ((uInt)best_len <= s->lookahead) return (uInt)best_len; + return s->lookahead; +} +#endif /* ASMV */ +#endif /* FASTEST */ + +/* --------------------------------------------------------------------------- + * Optimized version for level == 1 or strategy == Z_RLE only + */ +local uInt longest_match_fast(s, cur_match) + deflate_state *s; + IPos cur_match; /* current match */ +{ + register Bytef *scan = s->window + s->strstart; /* current string */ + register Bytef *match; /* matched string */ + register int len; /* length of current match */ + register Bytef *strend = s->window + s->strstart + MAX_MATCH; + + /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. + * It is easy to get rid of this optimization if necessary. + */ + Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); + + Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); + + Assert(cur_match < s->strstart, "no future"); + + match = s->window + cur_match; + + /* Return failure if the match length is less than 2: + */ + if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1; + + /* The check at best_len-1 can be removed because it will be made + * again later. (This heuristic is not always a win.) + * It is not necessary to compare scan[2] and match[2] since they + * are always equal when the other bytes match, given that + * the hash keys are equal and that HASH_BITS >= 8. + */ + scan += 2, match += 2; + Assert(*scan == *match, "match[2]?"); + + /* We check for insufficient lookahead only every 8th comparison; + * the 256th check will be made at strstart+258. + */ + do { + } while (*++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + scan < strend); + + Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + + len = MAX_MATCH - (int)(strend - scan); + + if (len < MIN_MATCH) return MIN_MATCH - 1; + + s->match_start = cur_match; + return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead; +} + +#ifdef DEBUG +/* =========================================================================== + * Check that the match at match_start is indeed a match. + */ +local void check_match(s, start, match, length) + deflate_state *s; + IPos start, match; + int length; +{ + /* check that the match is indeed a match */ + if (zmemcmp(s->window + match, + s->window + start, length) != EQUAL) { + fprintf(stderr, " start %u, match %u, length %d\n", + start, match, length); + do { + fprintf(stderr, "%c%c", s->window[match++], s->window[start++]); + } while (--length != 0); + z_error("invalid match"); + } + if (z_verbose > 1) { + fprintf(stderr,"\\[%d,%d]", start-match, length); + do { putc(s->window[start++], stderr); } while (--length != 0); + } +} +#else +# define check_match(s, start, match, length) +#endif /* DEBUG */ + +/* =========================================================================== + * Fill the window when the lookahead becomes insufficient. + * Updates strstart and lookahead. + * + * IN assertion: lookahead < MIN_LOOKAHEAD + * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD + * At least one byte has been read, or avail_in == 0; reads are + * performed for at least two bytes (required for the zip translate_eol + * option -- not supported here). + */ +local void fill_window(s) + deflate_state *s; +{ + register unsigned n, m; + register Posf *p; + unsigned more; /* Amount of free space at the end of the window. */ + uInt wsize = s->w_size; + + do { + more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); + + /* Deal with !@#$% 64K limit: */ + if (sizeof(int) <= 2) { + if (more == 0 && s->strstart == 0 && s->lookahead == 0) { + more = wsize; + + } else if (more == (unsigned)(-1)) { + /* Very unlikely, but possible on 16 bit machine if + * strstart == 0 && lookahead == 1 (input done a byte at time) + */ + more--; + } + } + + /* If the window is almost full and there is insufficient lookahead, + * move the upper half to the lower one to make room in the upper half. + */ + if (s->strstart >= wsize+MAX_DIST(s)) { + + zmemcpy(s->window, s->window+wsize, (unsigned)wsize); + s->match_start -= wsize; + s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ + s->block_start -= (long) wsize; + + /* Slide the hash table (could be avoided with 32 bit values + at the expense of memory usage). We slide even when level == 0 + to keep the hash table consistent if we switch back to level > 0 + later. (Using level 0 permanently is not an optimal usage of + zlib, so we don't care about this pathological case.) + */ + /* %%% avoid this when Z_RLE */ + n = s->hash_size; + p = &s->head[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m-wsize : NIL); + } while (--n); + + n = wsize; +#ifndef FASTEST + p = &s->prev[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m-wsize : NIL); + /* If n is not on any hash chain, prev[n] is garbage but + * its value will never be used. + */ + } while (--n); +#endif + more += wsize; + } + if (s->strm->avail_in == 0) return; + + /* If there was no sliding: + * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && + * more == window_size - lookahead - strstart + * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) + * => more >= window_size - 2*WSIZE + 2 + * In the BIG_MEM or MMAP case (not yet supported), + * window_size == input_size + MIN_LOOKAHEAD && + * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. + * Otherwise, window_size == 2*WSIZE so more >= 2. + * If there was sliding, more >= WSIZE. So in all cases, more >= 2. + */ + Assert(more >= 2, "more < 2"); + + n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more); + s->lookahead += n; + + /* Initialize the hash value now that we have some input: */ + if (s->lookahead >= MIN_MATCH) { + s->ins_h = s->window[s->strstart]; + UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); +#if MIN_MATCH != 3 + Call UPDATE_HASH() MIN_MATCH-3 more times +#endif + } + /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, + * but this is not important since only literal bytes will be emitted. + */ + + } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); +} + +/* =========================================================================== + * Flush the current block, with given end-of-file flag. + * IN assertion: strstart is set to the end of the current match. + */ +#define FLUSH_BLOCK_ONLY(s, eof) { \ + _tr_flush_block(s, (s->block_start >= 0L ? \ + (charf *)&s->window[(unsigned)s->block_start] : \ + (charf *)Z_NULL), \ + (ulg)((long)s->strstart - s->block_start), \ + (eof)); \ + s->block_start = s->strstart; \ + flush_pending(s->strm); \ + Tracev((stderr,"[FLUSH]")); \ +} + +/* Same but force premature exit if necessary. */ +#define FLUSH_BLOCK(s, eof) { \ + FLUSH_BLOCK_ONLY(s, eof); \ + if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \ +} + +/* =========================================================================== + * Copy without compression as much as possible from the input stream, return + * the current block state. + * This function does not insert new strings in the dictionary since + * uncompressible data is probably not useful. This function is used + * only for the level=0 compression option. + * NOTE: this function should be optimized to avoid extra copying from + * window to pending_buf. + */ +local block_state deflate_stored(s, flush) + deflate_state *s; + int flush; +{ + /* Stored blocks are limited to 0xffff bytes, pending_buf is limited + * to pending_buf_size, and each stored block has a 5 byte header: + */ + ulg max_block_size = 0xffff; + ulg max_start; + + if (max_block_size > s->pending_buf_size - 5) { + max_block_size = s->pending_buf_size - 5; + } + + /* Copy as much as possible from input to output: */ + for (;;) { + /* Fill the window as much as possible: */ + if (s->lookahead <= 1) { + + Assert(s->strstart < s->w_size+MAX_DIST(s) || + s->block_start >= (long)s->w_size, "slide too late"); + + fill_window(s); + if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more; + + if (s->lookahead == 0) break; /* flush the current block */ + } + Assert(s->block_start >= 0L, "block gone"); + + s->strstart += s->lookahead; + s->lookahead = 0; + + /* Emit a stored block if pending_buf will be full: */ + max_start = s->block_start + max_block_size; + if (s->strstart == 0 || (ulg)s->strstart >= max_start) { + /* strstart == 0 is possible when wraparound on 16-bit machine */ + s->lookahead = (uInt)(s->strstart - max_start); + s->strstart = (uInt)max_start; + FLUSH_BLOCK(s, 0); + } + /* Flush if we may have to slide, otherwise block_start may become + * negative and the data will be gone: + */ + if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) { + FLUSH_BLOCK(s, 0); + } + } + FLUSH_BLOCK(s, flush == Z_FINISH); + return flush == Z_FINISH ? finish_done : block_done; +} + +/* =========================================================================== + * Compress as much as possible from the input stream, return the current + * block state. + * This function does not perform lazy evaluation of matches and inserts + * new strings in the dictionary only for unmatched strings or for short + * matches. It is used only for the fast compression options. + */ +local block_state deflate_fast(s, flush) + deflate_state *s; + int flush; +{ + IPos hash_head = NIL; /* head of the hash chain */ + int bflush; /* set if current block must be flushed */ + + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s->lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { + return need_more; + } + if (s->lookahead == 0) break; /* flush the current block */ + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + if (s->lookahead >= MIN_MATCH) { + INSERT_STRING(s, s->strstart, hash_head); + } + + /* Find the longest match, discarding those <= prev_length. + * At this point we have always match_length < MIN_MATCH + */ + if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ +#ifdef FASTEST + if ((s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) || + (s->strategy == Z_RLE && s->strstart - hash_head == 1)) { + s->match_length = longest_match_fast (s, hash_head); + } +#else + if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) { + s->match_length = longest_match (s, hash_head); + } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) { + s->match_length = longest_match_fast (s, hash_head); + } +#endif + /* longest_match() or longest_match_fast() sets match_start */ + } + if (s->match_length >= MIN_MATCH) { + check_match(s, s->strstart, s->match_start, s->match_length); + + _tr_tally_dist(s, s->strstart - s->match_start, + s->match_length - MIN_MATCH, bflush); + + s->lookahead -= s->match_length; + + /* Insert new strings in the hash table only if the match length + * is not too large. This saves time but degrades compression. + */ +#ifndef FASTEST + if (s->match_length <= s->max_insert_length && + s->lookahead >= MIN_MATCH) { + s->match_length--; /* string at strstart already in table */ + do { + s->strstart++; + INSERT_STRING(s, s->strstart, hash_head); + /* strstart never exceeds WSIZE-MAX_MATCH, so there are + * always MIN_MATCH bytes ahead. + */ + } while (--s->match_length != 0); + s->strstart++; + } else +#endif + { + s->strstart += s->match_length; + s->match_length = 0; + s->ins_h = s->window[s->strstart]; + UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); +#if MIN_MATCH != 3 + Call UPDATE_HASH() MIN_MATCH-3 more times +#endif + /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not + * matter since it will be recomputed at next deflate call. + */ + } + } else { + /* No match, output a literal byte */ + Tracevv((stderr,"%c", s->window[s->strstart])); + _tr_tally_lit (s, s->window[s->strstart], bflush); + s->lookahead--; + s->strstart++; + } + if (bflush) FLUSH_BLOCK(s, 0); + } + FLUSH_BLOCK(s, flush == Z_FINISH); + return flush == Z_FINISH ? finish_done : block_done; +} + +#ifndef FASTEST +/* =========================================================================== + * Same as above, but achieves better compression. We use a lazy + * evaluation for matches: a match is finally adopted only if there is + * no better match at the next window position. + */ +local block_state deflate_slow(s, flush) + deflate_state *s; + int flush; +{ + IPos hash_head = NIL; /* head of hash chain */ + int bflush; /* set if current block must be flushed */ + + /* Process the input block. */ + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s->lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { + return need_more; + } + if (s->lookahead == 0) break; /* flush the current block */ + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + if (s->lookahead >= MIN_MATCH) { + INSERT_STRING(s, s->strstart, hash_head); + } + + /* Find the longest match, discarding those <= prev_length. + */ + s->prev_length = s->match_length, s->prev_match = s->match_start; + s->match_length = MIN_MATCH-1; + + if (hash_head != NIL && s->prev_length < s->max_lazy_match && + s->strstart - hash_head <= MAX_DIST(s)) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) { + s->match_length = longest_match (s, hash_head); + } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) { + s->match_length = longest_match_fast (s, hash_head); + } + /* longest_match() or longest_match_fast() sets match_start */ + + if (s->match_length <= 5 && (s->strategy == Z_FILTERED +#if TOO_FAR <= 32767 + || (s->match_length == MIN_MATCH && + s->strstart - s->match_start > TOO_FAR) +#endif + )) { + + /* If prev_match is also MIN_MATCH, match_start is garbage + * but we will ignore the current match anyway. + */ + s->match_length = MIN_MATCH-1; + } + } + /* If there was a match at the previous step and the current + * match is not better, output the previous match: + */ + if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { + uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; + /* Do not insert strings in hash table beyond this. */ + + check_match(s, s->strstart-1, s->prev_match, s->prev_length); + + _tr_tally_dist(s, s->strstart -1 - s->prev_match, + s->prev_length - MIN_MATCH, bflush); + + /* Insert in hash table all strings up to the end of the match. + * strstart-1 and strstart are already inserted. If there is not + * enough lookahead, the last two strings are not inserted in + * the hash table. + */ + s->lookahead -= s->prev_length-1; + s->prev_length -= 2; + do { + if (++s->strstart <= max_insert) { + INSERT_STRING(s, s->strstart, hash_head); + } + } while (--s->prev_length != 0); + s->match_available = 0; + s->match_length = MIN_MATCH-1; + s->strstart++; + + if (bflush) FLUSH_BLOCK(s, 0); + + } else if (s->match_available) { + /* If there was no match at the previous position, output a + * single literal. If there was a match but the current match + * is longer, truncate the previous match to a single literal. + */ + Tracevv((stderr,"%c", s->window[s->strstart-1])); + _tr_tally_lit(s, s->window[s->strstart-1], bflush); + if (bflush) { + FLUSH_BLOCK_ONLY(s, 0); + } + s->strstart++; + s->lookahead--; + if (s->strm->avail_out == 0) return need_more; + } else { + /* There is no previous match to compare with, wait for + * the next step to decide. + */ + s->match_available = 1; + s->strstart++; + s->lookahead--; + } + } + Assert (flush != Z_NO_FLUSH, "no flush?"); + if (s->match_available) { + Tracevv((stderr,"%c", s->window[s->strstart-1])); + _tr_tally_lit(s, s->window[s->strstart-1], bflush); + s->match_available = 0; + } + FLUSH_BLOCK(s, flush == Z_FINISH); + return flush == Z_FINISH ? finish_done : block_done; +} +#endif /* FASTEST */ + +#if 0 +/* =========================================================================== + * For Z_RLE, simply look for runs of bytes, generate matches only of distance + * one. Do not maintain a hash table. (It will be regenerated if this run of + * deflate switches away from Z_RLE.) + */ +local block_state deflate_rle(s, flush) + deflate_state *s; + int flush; +{ + int bflush; /* set if current block must be flushed */ + uInt run; /* length of run */ + uInt max; /* maximum length of run */ + uInt prev; /* byte at distance one to match */ + Bytef *scan; /* scan for end of run */ + + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the longest encodable run. + */ + if (s->lookahead < MAX_MATCH) { + fill_window(s); + if (s->lookahead < MAX_MATCH && flush == Z_NO_FLUSH) { + return need_more; + } + if (s->lookahead == 0) break; /* flush the current block */ + } + + /* See how many times the previous byte repeats */ + run = 0; + if (s->strstart > 0) { /* if there is a previous byte, that is */ + max = s->lookahead < MAX_MATCH ? s->lookahead : MAX_MATCH; + scan = s->window + s->strstart - 1; + prev = *scan++; + do { + if (*scan++ != prev) + break; + } while (++run < max); + } + + /* Emit match if have run of MIN_MATCH or longer, else emit literal */ + if (run >= MIN_MATCH) { + check_match(s, s->strstart, s->strstart - 1, run); + _tr_tally_dist(s, 1, run - MIN_MATCH, bflush); + s->lookahead -= run; + s->strstart += run; + } else { + /* No match, output a literal byte */ + Tracevv((stderr,"%c", s->window[s->strstart])); + _tr_tally_lit (s, s->window[s->strstart], bflush); + s->lookahead--; + s->strstart++; + } + if (bflush) FLUSH_BLOCK(s, 0); + } + FLUSH_BLOCK(s, flush == Z_FINISH); + return flush == Z_FINISH ? finish_done : block_done; +} +#endif diff --git a/cbits/gzio.c b/cbits/gzio.c new file mode 100644 --- /dev/null +++ b/cbits/gzio.c @@ -0,0 +1,1026 @@ +/* gzio.c -- IO on .gz files + * Copyright (C) 1995-2005 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + * + * Compile this file with -DNO_GZCOMPRESS to avoid the compression code. + */ + +/* @(#) $Id$ */ + +#include + +#include "zutil.h" + +#ifdef NO_DEFLATE /* for compatibility with old definition */ +# define NO_GZCOMPRESS +#endif + +#ifndef NO_DUMMY_DECL +struct internal_state {int dummy;}; /* for buggy compilers */ +#endif + +#ifndef Z_BUFSIZE +# ifdef MAXSEG_64K +# define Z_BUFSIZE 4096 /* minimize memory usage for 16-bit DOS */ +# else +# define Z_BUFSIZE 16384 +# endif +#endif +#ifndef Z_PRINTF_BUFSIZE +# define Z_PRINTF_BUFSIZE 4096 +#endif + +#ifdef __MVS__ +# pragma map (fdopen , "\174\174FDOPEN") + FILE *fdopen(int, const char *); +#endif + +#ifndef STDC +extern voidp malloc OF((uInt size)); +extern void free OF((voidpf ptr)); +#endif + +#define ALLOC(size) malloc(size) +#define TRYFREE(p) {if (p) free(p);} + +static int const gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */ + +/* gzip flag byte */ +#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ +#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ +#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ +#define ORIG_NAME 0x08 /* bit 3 set: original file name present */ +#define COMMENT 0x10 /* bit 4 set: file comment present */ +#define RESERVED 0xE0 /* bits 5..7: reserved */ + +typedef struct gz_stream { + z_stream stream; + int z_err; /* error code for last stream operation */ + int z_eof; /* set if end of input file */ + FILE *file; /* .gz file */ + Byte *inbuf; /* input buffer */ + Byte *outbuf; /* output buffer */ + uLong crc; /* crc32 of uncompressed data */ + char *msg; /* error message */ + char *path; /* path name for debugging only */ + int transparent; /* 1 if input file is not a .gz file */ + char mode; /* 'w' or 'r' */ + z_off_t start; /* start of compressed data in file (header skipped) */ + z_off_t in; /* bytes into deflate or inflate */ + z_off_t out; /* bytes out of deflate or inflate */ + int back; /* one character push-back */ + int last; /* true if push-back is last character */ +} gz_stream; + + +local gzFile gz_open OF((const char *path, const char *mode, int fd)); +local int do_flush OF((gzFile file, int flush)); +local int get_byte OF((gz_stream *s)); +local void check_header OF((gz_stream *s)); +local int destroy OF((gz_stream *s)); +local void putLong OF((FILE *file, uLong x)); +local uLong getLong OF((gz_stream *s)); + +/* =========================================================================== + Opens a gzip (.gz) file for reading or writing. The mode parameter + is as in fopen ("rb" or "wb"). The file is given either by file descriptor + or path name (if fd == -1). + gz_open returns NULL if the file could not be opened or if there was + insufficient memory to allocate the (de)compression state; errno + can be checked to distinguish the two cases (if errno is zero, the + zlib error is Z_MEM_ERROR). +*/ +local gzFile gz_open (path, mode, fd) + const char *path; + const char *mode; + int fd; +{ + int err; + int level = Z_DEFAULT_COMPRESSION; /* compression level */ + int strategy = Z_DEFAULT_STRATEGY; /* compression strategy */ + char *p = (char*)mode; + gz_stream *s; + char fmode[80]; /* copy of mode, without the compression level */ + char *m = fmode; + + if (!path || !mode) return Z_NULL; + + s = (gz_stream *)ALLOC(sizeof(gz_stream)); + if (!s) return Z_NULL; + + s->stream.zalloc = (alloc_func)0; + s->stream.zfree = (free_func)0; + s->stream.opaque = (voidpf)0; + s->stream.next_in = s->inbuf = Z_NULL; + s->stream.next_out = s->outbuf = Z_NULL; + s->stream.avail_in = s->stream.avail_out = 0; + s->file = NULL; + s->z_err = Z_OK; + s->z_eof = 0; + s->in = 0; + s->out = 0; + s->back = EOF; + s->crc = crc32(0L, Z_NULL, 0); + s->msg = NULL; + s->transparent = 0; + + s->path = (char*)ALLOC(strlen(path)+1); + if (s->path == NULL) { + return destroy(s), (gzFile)Z_NULL; + } + strcpy(s->path, path); /* do this early for debugging */ + + s->mode = '\0'; + do { + if (*p == 'r') s->mode = 'r'; + if (*p == 'w' || *p == 'a') s->mode = 'w'; + if (*p >= '0' && *p <= '9') { + level = *p - '0'; + } else if (*p == 'f') { + strategy = Z_FILTERED; + } else if (*p == 'h') { + strategy = Z_HUFFMAN_ONLY; + } else if (*p == 'R') { + strategy = Z_RLE; + } else { + *m++ = *p; /* copy the mode */ + } + } while (*p++ && m != fmode + sizeof(fmode)); + if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL; + + if (s->mode == 'w') { +#ifdef NO_GZCOMPRESS + err = Z_STREAM_ERROR; +#else + err = deflateInit2(&(s->stream), level, + Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, strategy); + /* windowBits is passed < 0 to suppress zlib header */ + + s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE); +#endif + if (err != Z_OK || s->outbuf == Z_NULL) { + return destroy(s), (gzFile)Z_NULL; + } + } else { + s->stream.next_in = s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); + + err = inflateInit2(&(s->stream), -MAX_WBITS); + /* windowBits is passed < 0 to tell that there is no zlib header. + * Note that in this case inflate *requires* an extra "dummy" byte + * after the compressed stream in order to complete decompression and + * return Z_STREAM_END. Here the gzip CRC32 ensures that 4 bytes are + * present after the compressed stream. + */ + if (err != Z_OK || s->inbuf == Z_NULL) { + return destroy(s), (gzFile)Z_NULL; + } + } + s->stream.avail_out = Z_BUFSIZE; + + errno = 0; + s->file = fd < 0 ? F_OPEN(path, fmode) : (FILE*)fdopen(fd, fmode); + + if (s->file == NULL) { + return destroy(s), (gzFile)Z_NULL; + } + if (s->mode == 'w') { + /* Write a very simple .gz header: + */ + fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1], + Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE); + s->start = 10L; + /* We use 10L instead of ftell(s->file) to because ftell causes an + * fflush on some systems. This version of the library doesn't use + * start anyway in write mode, so this initialization is not + * necessary. + */ + } else { + check_header(s); /* skip the .gz header */ + s->start = ftell(s->file) - s->stream.avail_in; + } + + return (gzFile)s; +} + +/* =========================================================================== + Opens a gzip (.gz) file for reading or writing. +*/ +gzFile ZEXPORT gzopen (path, mode) + const char *path; + const char *mode; +{ + return gz_open (path, mode, -1); +} + +/* =========================================================================== + Associate a gzFile with the file descriptor fd. fd is not dup'ed here + to mimic the behavio(u)r of fdopen. +*/ +gzFile ZEXPORT gzdopen (fd, mode) + int fd; + const char *mode; +{ + char name[46]; /* allow for up to 128-bit integers */ + + if (fd < 0) return (gzFile)Z_NULL; + sprintf(name, "", fd); /* for debugging */ + + return gz_open (name, mode, fd); +} + +/* =========================================================================== + * Update the compression level and strategy + */ +int ZEXPORT gzsetparams (file, level, strategy) + gzFile file; + int level; + int strategy; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; + + /* Make room to allow flushing */ + if (s->stream.avail_out == 0) { + + s->stream.next_out = s->outbuf; + if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) { + s->z_err = Z_ERRNO; + } + s->stream.avail_out = Z_BUFSIZE; + } + + return deflateParams (&(s->stream), level, strategy); +} + +/* =========================================================================== + Read a byte from a gz_stream; update next_in and avail_in. Return EOF + for end of file. + IN assertion: the stream s has been sucessfully opened for reading. +*/ +local int get_byte(s) + gz_stream *s; +{ + if (s->z_eof) return EOF; + if (s->stream.avail_in == 0) { + errno = 0; + s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file); + if (s->stream.avail_in == 0) { + s->z_eof = 1; + if (ferror(s->file)) s->z_err = Z_ERRNO; + return EOF; + } + s->stream.next_in = s->inbuf; + } + s->stream.avail_in--; + return *(s->stream.next_in)++; +} + +/* =========================================================================== + Check the gzip header of a gz_stream opened for reading. Set the stream + mode to transparent if the gzip magic header is not present; set s->err + to Z_DATA_ERROR if the magic header is present but the rest of the header + is incorrect. + IN assertion: the stream s has already been created sucessfully; + s->stream.avail_in is zero for the first time, but may be non-zero + for concatenated .gz files. +*/ +local void check_header(s) + gz_stream *s; +{ + int method; /* method byte */ + int flags; /* flags byte */ + uInt len; + int c; + + /* Assure two bytes in the buffer so we can peek ahead -- handle case + where first byte of header is at the end of the buffer after the last + gzip segment */ + len = s->stream.avail_in; + if (len < 2) { + if (len) s->inbuf[0] = s->stream.next_in[0]; + errno = 0; + len = (uInt)fread(s->inbuf + len, 1, Z_BUFSIZE >> len, s->file); + if (len == 0 && ferror(s->file)) s->z_err = Z_ERRNO; + s->stream.avail_in += len; + s->stream.next_in = s->inbuf; + if (s->stream.avail_in < 2) { + s->transparent = s->stream.avail_in; + return; + } + } + + /* Peek ahead to check the gzip magic header */ + if (s->stream.next_in[0] != gz_magic[0] || + s->stream.next_in[1] != gz_magic[1]) { + s->transparent = 1; + return; + } + s->stream.avail_in -= 2; + s->stream.next_in += 2; + + /* Check the rest of the gzip header */ + method = get_byte(s); + flags = get_byte(s); + if (method != Z_DEFLATED || (flags & RESERVED) != 0) { + s->z_err = Z_DATA_ERROR; + return; + } + + /* Discard time, xflags and OS code: */ + for (len = 0; len < 6; len++) (void)get_byte(s); + + if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */ + len = (uInt)get_byte(s); + len += ((uInt)get_byte(s))<<8; + /* len is garbage if EOF but the loop below will quit anyway */ + while (len-- != 0 && get_byte(s) != EOF) ; + } + if ((flags & ORIG_NAME) != 0) { /* skip the original file name */ + while ((c = get_byte(s)) != 0 && c != EOF) ; + } + if ((flags & COMMENT) != 0) { /* skip the .gz file comment */ + while ((c = get_byte(s)) != 0 && c != EOF) ; + } + if ((flags & HEAD_CRC) != 0) { /* skip the header crc */ + for (len = 0; len < 2; len++) (void)get_byte(s); + } + s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK; +} + + /* =========================================================================== + * Cleanup then free the given gz_stream. Return a zlib error code. + Try freeing in the reverse order of allocations. + */ +local int destroy (s) + gz_stream *s; +{ + int err = Z_OK; + + if (!s) return Z_STREAM_ERROR; + + TRYFREE(s->msg); + + if (s->stream.state != NULL) { + if (s->mode == 'w') { +#ifdef NO_GZCOMPRESS + err = Z_STREAM_ERROR; +#else + err = deflateEnd(&(s->stream)); +#endif + } else if (s->mode == 'r') { + err = inflateEnd(&(s->stream)); + } + } + if (s->file != NULL && fclose(s->file)) { +#ifdef ESPIPE + if (errno != ESPIPE) /* fclose is broken for pipes in HP/UX */ +#endif + err = Z_ERRNO; + } + if (s->z_err < 0) err = s->z_err; + + TRYFREE(s->inbuf); + TRYFREE(s->outbuf); + TRYFREE(s->path); + TRYFREE(s); + return err; +} + +/* =========================================================================== + Reads the given number of uncompressed bytes from the compressed file. + gzread returns the number of bytes actually read (0 for end of file). +*/ +int ZEXPORT gzread (file, buf, len) + gzFile file; + voidp buf; + unsigned len; +{ + gz_stream *s = (gz_stream*)file; + Bytef *start = (Bytef*)buf; /* starting point for crc computation */ + Byte *next_out; /* == stream.next_out but not forced far (for MSDOS) */ + + if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR; + + if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1; + if (s->z_err == Z_STREAM_END) return 0; /* EOF */ + + next_out = (Byte*)buf; + s->stream.next_out = (Bytef*)buf; + s->stream.avail_out = len; + + if (s->stream.avail_out && s->back != EOF) { + *next_out++ = s->back; + s->stream.next_out++; + s->stream.avail_out--; + s->back = EOF; + s->out++; + start++; + if (s->last) { + s->z_err = Z_STREAM_END; + return 1; + } + } + + while (s->stream.avail_out != 0) { + + if (s->transparent) { + /* Copy first the lookahead bytes: */ + uInt n = s->stream.avail_in; + if (n > s->stream.avail_out) n = s->stream.avail_out; + if (n > 0) { + zmemcpy(s->stream.next_out, s->stream.next_in, n); + next_out += n; + s->stream.next_out = next_out; + s->stream.next_in += n; + s->stream.avail_out -= n; + s->stream.avail_in -= n; + } + if (s->stream.avail_out > 0) { + s->stream.avail_out -= + (uInt)fread(next_out, 1, s->stream.avail_out, s->file); + } + len -= s->stream.avail_out; + s->in += len; + s->out += len; + if (len == 0) s->z_eof = 1; + return (int)len; + } + if (s->stream.avail_in == 0 && !s->z_eof) { + + errno = 0; + s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file); + if (s->stream.avail_in == 0) { + s->z_eof = 1; + if (ferror(s->file)) { + s->z_err = Z_ERRNO; + break; + } + } + s->stream.next_in = s->inbuf; + } + s->in += s->stream.avail_in; + s->out += s->stream.avail_out; + s->z_err = inflate(&(s->stream), Z_NO_FLUSH); + s->in -= s->stream.avail_in; + s->out -= s->stream.avail_out; + + if (s->z_err == Z_STREAM_END) { + /* Check CRC and original size */ + s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start)); + start = s->stream.next_out; + + if (getLong(s) != s->crc) { + s->z_err = Z_DATA_ERROR; + } else { + (void)getLong(s); + /* The uncompressed length returned by above getlong() may be + * different from s->out in case of concatenated .gz files. + * Check for such files: + */ + check_header(s); + if (s->z_err == Z_OK) { + inflateReset(&(s->stream)); + s->crc = crc32(0L, Z_NULL, 0); + } + } + } + if (s->z_err != Z_OK || s->z_eof) break; + } + s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start)); + + if (len == s->stream.avail_out && + (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO)) + return -1; + return (int)(len - s->stream.avail_out); +} + + +/* =========================================================================== + Reads one byte from the compressed file. gzgetc returns this byte + or -1 in case of end of file or error. +*/ +int ZEXPORT gzgetc(file) + gzFile file; +{ + unsigned char c; + + return gzread(file, &c, 1) == 1 ? c : -1; +} + + +/* =========================================================================== + Push one byte back onto the stream. +*/ +int ZEXPORT gzungetc(c, file) + int c; + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'r' || c == EOF || s->back != EOF) return EOF; + s->back = c; + s->out--; + s->last = (s->z_err == Z_STREAM_END); + if (s->last) s->z_err = Z_OK; + s->z_eof = 0; + return c; +} + + +/* =========================================================================== + Reads bytes from the compressed file until len-1 characters are + read, or a newline character is read and transferred to buf, or an + end-of-file condition is encountered. The string is then terminated + with a null character. + gzgets returns buf, or Z_NULL in case of error. + + The current implementation is not optimized at all. +*/ +char * ZEXPORT gzgets(file, buf, len) + gzFile file; + char *buf; + int len; +{ + char *b = buf; + if (buf == Z_NULL || len <= 0) return Z_NULL; + + while (--len > 0 && gzread(file, buf, 1) == 1 && *buf++ != '\n') ; + *buf = '\0'; + return b == buf && len > 0 ? Z_NULL : b; +} + + +#ifndef NO_GZCOMPRESS +/* =========================================================================== + Writes the given number of uncompressed bytes into the compressed file. + gzwrite returns the number of bytes actually written (0 in case of error). +*/ +int ZEXPORT gzwrite (file, buf, len) + gzFile file; + voidpc buf; + unsigned len; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; + + s->stream.next_in = (Bytef*)buf; + s->stream.avail_in = len; + + while (s->stream.avail_in != 0) { + + if (s->stream.avail_out == 0) { + + s->stream.next_out = s->outbuf; + if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) { + s->z_err = Z_ERRNO; + break; + } + s->stream.avail_out = Z_BUFSIZE; + } + s->in += s->stream.avail_in; + s->out += s->stream.avail_out; + s->z_err = deflate(&(s->stream), Z_NO_FLUSH); + s->in -= s->stream.avail_in; + s->out -= s->stream.avail_out; + if (s->z_err != Z_OK) break; + } + s->crc = crc32(s->crc, (const Bytef *)buf, len); + + return (int)(len - s->stream.avail_in); +} + + +/* =========================================================================== + Converts, formats, and writes the args to the compressed file under + control of the format string, as in fprintf. gzprintf returns the number of + uncompressed bytes actually written (0 in case of error). +*/ +#ifdef STDC +#include + +int ZEXPORTVA gzprintf (gzFile file, const char *format, /* args */ ...) +{ + char buf[Z_PRINTF_BUFSIZE]; + va_list va; + int len; + + buf[sizeof(buf) - 1] = 0; + va_start(va, format); +#ifdef NO_vsnprintf +# ifdef HAS_vsprintf_void + (void)vsprintf(buf, format, va); + va_end(va); + for (len = 0; len < sizeof(buf); len++) + if (buf[len] == 0) break; +# else + len = vsprintf(buf, format, va); + va_end(va); +# endif +#else +# ifdef HAS_vsnprintf_void + (void)vsnprintf(buf, sizeof(buf), format, va); + va_end(va); + len = strlen(buf); +# else + len = vsnprintf(buf, sizeof(buf), format, va); + va_end(va); +# endif +#endif + if (len <= 0 || len >= (int)sizeof(buf) || buf[sizeof(buf) - 1] != 0) + return 0; + return gzwrite(file, buf, (unsigned)len); +} +#else /* not ANSI C */ + +int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, + a11, a12, a13, a14, a15, a16, a17, a18, a19, a20) + gzFile file; + const char *format; + int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, + a11, a12, a13, a14, a15, a16, a17, a18, a19, a20; +{ + char buf[Z_PRINTF_BUFSIZE]; + int len; + + buf[sizeof(buf) - 1] = 0; +#ifdef NO_snprintf +# ifdef HAS_sprintf_void + sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); + for (len = 0; len < sizeof(buf); len++) + if (buf[len] == 0) break; +# else + len = sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); +# endif +#else +# ifdef HAS_snprintf_void + snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); + len = strlen(buf); +# else + len = snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); +# endif +#endif + if (len <= 0 || len >= sizeof(buf) || buf[sizeof(buf) - 1] != 0) + return 0; + return gzwrite(file, buf, len); +} +#endif + +/* =========================================================================== + Writes c, converted to an unsigned char, into the compressed file. + gzputc returns the value that was written, or -1 in case of error. +*/ +int ZEXPORT gzputc(file, c) + gzFile file; + int c; +{ + unsigned char cc = (unsigned char) c; /* required for big endian systems */ + + return gzwrite(file, &cc, 1) == 1 ? (int)cc : -1; +} + + +/* =========================================================================== + Writes the given null-terminated string to the compressed file, excluding + the terminating null character. + gzputs returns the number of characters written, or -1 in case of error. +*/ +int ZEXPORT gzputs(file, s) + gzFile file; + const char *s; +{ + return gzwrite(file, (char*)s, (unsigned)strlen(s)); +} + + +/* =========================================================================== + Flushes all pending output into the compressed file. The parameter + flush is as in the deflate() function. +*/ +local int do_flush (file, flush) + gzFile file; + int flush; +{ + uInt len; + int done = 0; + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; + + s->stream.avail_in = 0; /* should be zero already anyway */ + + for (;;) { + len = Z_BUFSIZE - s->stream.avail_out; + + if (len != 0) { + if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) { + s->z_err = Z_ERRNO; + return Z_ERRNO; + } + s->stream.next_out = s->outbuf; + s->stream.avail_out = Z_BUFSIZE; + } + if (done) break; + s->out += s->stream.avail_out; + s->z_err = deflate(&(s->stream), flush); + s->out -= s->stream.avail_out; + + /* Ignore the second of two consecutive flushes: */ + if (len == 0 && s->z_err == Z_BUF_ERROR) s->z_err = Z_OK; + + /* deflate has finished flushing only when it hasn't used up + * all the available space in the output buffer: + */ + done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END); + + if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) break; + } + return s->z_err == Z_STREAM_END ? Z_OK : s->z_err; +} + +int ZEXPORT gzflush (file, flush) + gzFile file; + int flush; +{ + gz_stream *s = (gz_stream*)file; + int err = do_flush (file, flush); + + if (err) return err; + fflush(s->file); + return s->z_err == Z_STREAM_END ? Z_OK : s->z_err; +} +#endif /* NO_GZCOMPRESS */ + +/* =========================================================================== + Sets the starting position for the next gzread or gzwrite on the given + compressed file. The offset represents a number of bytes in the + gzseek returns the resulting offset location as measured in bytes from + the beginning of the uncompressed stream, or -1 in case of error. + SEEK_END is not implemented, returns error. + In this version of the library, gzseek can be extremely slow. +*/ +z_off_t ZEXPORT gzseek (file, offset, whence) + gzFile file; + z_off_t offset; + int whence; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || whence == SEEK_END || + s->z_err == Z_ERRNO || s->z_err == Z_DATA_ERROR) { + return -1L; + } + + if (s->mode == 'w') { +#ifdef NO_GZCOMPRESS + return -1L; +#else + if (whence == SEEK_SET) { + offset -= s->in; + } + if (offset < 0) return -1L; + + /* At this point, offset is the number of zero bytes to write. */ + if (s->inbuf == Z_NULL) { + s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); /* for seeking */ + if (s->inbuf == Z_NULL) return -1L; + zmemzero(s->inbuf, Z_BUFSIZE); + } + while (offset > 0) { + uInt size = Z_BUFSIZE; + if (offset < Z_BUFSIZE) size = (uInt)offset; + + size = gzwrite(file, s->inbuf, size); + if (size == 0) return -1L; + + offset -= size; + } + return s->in; +#endif + } + /* Rest of function is for reading only */ + + /* compute absolute position */ + if (whence == SEEK_CUR) { + offset += s->out; + } + if (offset < 0) return -1L; + + if (s->transparent) { + /* map to fseek */ + s->back = EOF; + s->stream.avail_in = 0; + s->stream.next_in = s->inbuf; + if (fseek(s->file, offset, SEEK_SET) < 0) return -1L; + + s->in = s->out = offset; + return offset; + } + + /* For a negative seek, rewind and use positive seek */ + if (offset >= s->out) { + offset -= s->out; + } else if (gzrewind(file) < 0) { + return -1L; + } + /* offset is now the number of bytes to skip. */ + + if (offset != 0 && s->outbuf == Z_NULL) { + s->outbuf = (Byte*)ALLOC(Z_BUFSIZE); + if (s->outbuf == Z_NULL) return -1L; + } + if (offset && s->back != EOF) { + s->back = EOF; + s->out++; + offset--; + if (s->last) s->z_err = Z_STREAM_END; + } + while (offset > 0) { + int size = Z_BUFSIZE; + if (offset < Z_BUFSIZE) size = (int)offset; + + size = gzread(file, s->outbuf, (uInt)size); + if (size <= 0) return -1L; + offset -= size; + } + return s->out; +} + +/* =========================================================================== + Rewinds input file. +*/ +int ZEXPORT gzrewind (file) + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'r') return -1; + + s->z_err = Z_OK; + s->z_eof = 0; + s->back = EOF; + s->stream.avail_in = 0; + s->stream.next_in = s->inbuf; + s->crc = crc32(0L, Z_NULL, 0); + if (!s->transparent) (void)inflateReset(&s->stream); + s->in = 0; + s->out = 0; + return fseek(s->file, s->start, SEEK_SET); +} + +/* =========================================================================== + Returns the starting position for the next gzread or gzwrite on the + given compressed file. This position represents a number of bytes in the + uncompressed data stream. +*/ +z_off_t ZEXPORT gztell (file) + gzFile file; +{ + return gzseek(file, 0L, SEEK_CUR); +} + +/* =========================================================================== + Returns 1 when EOF has previously been detected reading the given + input stream, otherwise zero. +*/ +int ZEXPORT gzeof (file) + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + /* With concatenated compressed files that can have embedded + * crc trailers, z_eof is no longer the only/best indicator of EOF + * on a gz_stream. Handle end-of-stream error explicitly here. + */ + if (s == NULL || s->mode != 'r') return 0; + if (s->z_eof) return 1; + return s->z_err == Z_STREAM_END; +} + +/* =========================================================================== + Returns 1 if reading and doing so transparently, otherwise zero. +*/ +int ZEXPORT gzdirect (file) + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL || s->mode != 'r') return 0; + return s->transparent; +} + +/* =========================================================================== + Outputs a long in LSB order to the given file +*/ +local void putLong (file, x) + FILE *file; + uLong x; +{ + int n; + for (n = 0; n < 4; n++) { + fputc((int)(x & 0xff), file); + x >>= 8; + } +} + +/* =========================================================================== + Reads a long in LSB order from the given gz_stream. Sets z_err in case + of error. +*/ +local uLong getLong (s) + gz_stream *s; +{ + uLong x = (uLong)get_byte(s); + int c; + + x += ((uLong)get_byte(s))<<8; + x += ((uLong)get_byte(s))<<16; + c = get_byte(s); + if (c == EOF) s->z_err = Z_DATA_ERROR; + x += ((uLong)c)<<24; + return x; +} + +/* =========================================================================== + Flushes all pending output if necessary, closes the compressed file + and deallocates all the (de)compression state. +*/ +int ZEXPORT gzclose (file) + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL) return Z_STREAM_ERROR; + + if (s->mode == 'w') { +#ifdef NO_GZCOMPRESS + return Z_STREAM_ERROR; +#else + if (do_flush (file, Z_FINISH) != Z_OK) + return destroy((gz_stream*)file); + + putLong (s->file, s->crc); + putLong (s->file, (uLong)(s->in & 0xffffffff)); +#endif + } + return destroy((gz_stream*)file); +} + +#ifdef STDC +# define zstrerror(errnum) strerror(errnum) +#else +# define zstrerror(errnum) "" +#endif + +/* =========================================================================== + Returns the error message for the last error which occurred on the + given compressed file. errnum is set to zlib error number. If an + error occurred in the file system and not in the compression library, + errnum is set to Z_ERRNO and the application may consult errno + to get the exact error code. +*/ +const char * ZEXPORT gzerror (file, errnum) + gzFile file; + int *errnum; +{ + char *m; + gz_stream *s = (gz_stream*)file; + + if (s == NULL) { + *errnum = Z_STREAM_ERROR; + return (const char*)ERR_MSG(Z_STREAM_ERROR); + } + *errnum = s->z_err; + if (*errnum == Z_OK) return (const char*)""; + + m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg); + + if (m == NULL || *m == '\0') m = (char*)ERR_MSG(s->z_err); + + TRYFREE(s->msg); + s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3); + if (s->msg == Z_NULL) return (const char*)ERR_MSG(Z_MEM_ERROR); + strcpy(s->msg, s->path); + strcat(s->msg, ": "); + strcat(s->msg, m); + return (const char*)s->msg; +} + +/* =========================================================================== + Clear the error and end-of-file flags, and do the same for the real file. +*/ +void ZEXPORT gzclearerr (file) + gzFile file; +{ + gz_stream *s = (gz_stream*)file; + + if (s == NULL) return; + if (s->z_err != Z_STREAM_END) s->z_err = Z_OK; + s->z_eof = 0; + clearerr(s->file); +} diff --git a/cbits/infback.c b/cbits/infback.c new file mode 100644 --- /dev/null +++ b/cbits/infback.c @@ -0,0 +1,623 @@ +/* infback.c -- inflate using a call-back interface + * Copyright (C) 1995-2005 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + This code is largely copied from inflate.c. Normally either infback.o or + inflate.o would be linked into an application--not both. The interface + with inffast.c is retained so that optimized assembler-coded versions of + inflate_fast() can be used with either inflate.c or infback.c. + */ + +#include "zutil.h" +#include "inftrees.h" +#include "inflate.h" +#include "inffast.h" + +/* function prototypes */ +local void fixedtables OF((struct inflate_state FAR *state)); + +/* + strm provides memory allocation functions in zalloc and zfree, or + Z_NULL to use the library memory allocation functions. + + windowBits is in the range 8..15, and window is a user-supplied + window and output buffer that is 2**windowBits bytes. + */ +int ZEXPORT inflateBackInit_(strm, windowBits, window, version, stream_size) +z_streamp strm; +int windowBits; +unsigned char FAR *window; +const char *version; +int stream_size; +{ + struct inflate_state FAR *state; + + if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || + stream_size != (int)(sizeof(z_stream))) + return Z_VERSION_ERROR; + if (strm == Z_NULL || window == Z_NULL || + windowBits < 8 || windowBits > 15) + return Z_STREAM_ERROR; + strm->msg = Z_NULL; /* in case we return an error */ + if (strm->zalloc == (alloc_func)0) { + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; + } + if (strm->zfree == (free_func)0) strm->zfree = zcfree; + state = (struct inflate_state FAR *)ZALLOC(strm, 1, + sizeof(struct inflate_state)); + if (state == Z_NULL) return Z_MEM_ERROR; + Tracev((stderr, "inflate: allocated\n")); + strm->state = (struct internal_state FAR *)state; + state->dmax = 32768U; + state->wbits = windowBits; + state->wsize = 1U << windowBits; + state->window = window; + state->write = 0; + state->whave = 0; + return Z_OK; +} + +/* + Return state with length and distance decoding tables and index sizes set to + fixed code decoding. Normally this returns fixed tables from inffixed.h. + If BUILDFIXED is defined, then instead this routine builds the tables the + first time it's called, and returns those tables the first time and + thereafter. This reduces the size of the code by about 2K bytes, in + exchange for a little execution time. However, BUILDFIXED should not be + used for threaded applications, since the rewriting of the tables and virgin + may not be thread-safe. + */ +local void fixedtables(state) +struct inflate_state FAR *state; +{ +#ifdef BUILDFIXED + static int virgin = 1; + static code *lenfix, *distfix; + static code fixed[544]; + + /* build fixed huffman tables if first call (may not be thread safe) */ + if (virgin) { + unsigned sym, bits; + static code *next; + + /* literal/length table */ + sym = 0; + while (sym < 144) state->lens[sym++] = 8; + while (sym < 256) state->lens[sym++] = 9; + while (sym < 280) state->lens[sym++] = 7; + while (sym < 288) state->lens[sym++] = 8; + next = fixed; + lenfix = next; + bits = 9; + inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); + + /* distance table */ + sym = 0; + while (sym < 32) state->lens[sym++] = 5; + distfix = next; + bits = 5; + inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); + + /* do this just once */ + virgin = 0; + } +#else /* !BUILDFIXED */ +# include "inffixed.h" +#endif /* BUILDFIXED */ + state->lencode = lenfix; + state->lenbits = 9; + state->distcode = distfix; + state->distbits = 5; +} + +/* Macros for inflateBack(): */ + +/* Load returned state from inflate_fast() */ +#define LOAD() \ + do { \ + put = strm->next_out; \ + left = strm->avail_out; \ + next = strm->next_in; \ + have = strm->avail_in; \ + hold = state->hold; \ + bits = state->bits; \ + } while (0) + +/* Set state from registers for inflate_fast() */ +#define RESTORE() \ + do { \ + strm->next_out = put; \ + strm->avail_out = left; \ + strm->next_in = next; \ + strm->avail_in = have; \ + state->hold = hold; \ + state->bits = bits; \ + } while (0) + +/* Clear the input bit accumulator */ +#define INITBITS() \ + do { \ + hold = 0; \ + bits = 0; \ + } while (0) + +/* Assure that some input is available. If input is requested, but denied, + then return a Z_BUF_ERROR from inflateBack(). */ +#define PULL() \ + do { \ + if (have == 0) { \ + have = in(in_desc, &next); \ + if (have == 0) { \ + next = Z_NULL; \ + ret = Z_BUF_ERROR; \ + goto inf_leave; \ + } \ + } \ + } while (0) + +/* Get a byte of input into the bit accumulator, or return from inflateBack() + with an error if there is no input available. */ +#define PULLBYTE() \ + do { \ + PULL(); \ + have--; \ + hold += (unsigned long)(*next++) << bits; \ + bits += 8; \ + } while (0) + +/* Assure that there are at least n bits in the bit accumulator. If there is + not enough available input to do that, then return from inflateBack() with + an error. */ +#define NEEDBITS(n) \ + do { \ + while (bits < (unsigned)(n)) \ + PULLBYTE(); \ + } while (0) + +/* Return the low n bits of the bit accumulator (n < 16) */ +#define BITS(n) \ + ((unsigned)hold & ((1U << (n)) - 1)) + +/* Remove n bits from the bit accumulator */ +#define DROPBITS(n) \ + do { \ + hold >>= (n); \ + bits -= (unsigned)(n); \ + } while (0) + +/* Remove zero to seven bits as needed to go to a byte boundary */ +#define BYTEBITS() \ + do { \ + hold >>= bits & 7; \ + bits -= bits & 7; \ + } while (0) + +/* Assure that some output space is available, by writing out the window + if it's full. If the write fails, return from inflateBack() with a + Z_BUF_ERROR. */ +#define ROOM() \ + do { \ + if (left == 0) { \ + put = state->window; \ + left = state->wsize; \ + state->whave = left; \ + if (out(out_desc, put, left)) { \ + ret = Z_BUF_ERROR; \ + goto inf_leave; \ + } \ + } \ + } while (0) + +/* + strm provides the memory allocation functions and window buffer on input, + and provides information on the unused input on return. For Z_DATA_ERROR + returns, strm will also provide an error message. + + in() and out() are the call-back input and output functions. When + inflateBack() needs more input, it calls in(). When inflateBack() has + filled the window with output, or when it completes with data in the + window, it calls out() to write out the data. The application must not + change the provided input until in() is called again or inflateBack() + returns. The application must not change the window/output buffer until + inflateBack() returns. + + in() and out() are called with a descriptor parameter provided in the + inflateBack() call. This parameter can be a structure that provides the + information required to do the read or write, as well as accumulated + information on the input and output such as totals and check values. + + in() should return zero on failure. out() should return non-zero on + failure. If either in() or out() fails, than inflateBack() returns a + Z_BUF_ERROR. strm->next_in can be checked for Z_NULL to see whether it + was in() or out() that caused in the error. Otherwise, inflateBack() + returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format + error, or Z_MEM_ERROR if it could not allocate memory for the state. + inflateBack() can also return Z_STREAM_ERROR if the input parameters + are not correct, i.e. strm is Z_NULL or the state was not initialized. + */ +int ZEXPORT inflateBack(strm, in, in_desc, out, out_desc) +z_streamp strm; +in_func in; +void FAR *in_desc; +out_func out; +void FAR *out_desc; +{ + struct inflate_state FAR *state; + unsigned char FAR *next; /* next input */ + unsigned char FAR *put; /* next output */ + unsigned have, left; /* available input and output */ + unsigned long hold; /* bit buffer */ + unsigned bits; /* bits in bit buffer */ + unsigned copy; /* number of stored or match bytes to copy */ + unsigned char FAR *from; /* where to copy match bytes from */ + code this; /* current decoding table entry */ + code last; /* parent table entry */ + unsigned len; /* length to copy for repeats, bits to drop */ + int ret; /* return code */ + static const unsigned short order[19] = /* permutation of code lengths */ + {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + + /* Check that the strm exists and that the state was initialized */ + if (strm == Z_NULL || strm->state == Z_NULL) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + + /* Reset the state */ + strm->msg = Z_NULL; + state->mode = TYPE; + state->last = 0; + state->whave = 0; + next = strm->next_in; + have = next != Z_NULL ? strm->avail_in : 0; + hold = 0; + bits = 0; + put = state->window; + left = state->wsize; + + /* Inflate until end of block marked as last */ + for (;;) + switch (state->mode) { + case TYPE: + /* determine and dispatch block type */ + if (state->last) { + BYTEBITS(); + state->mode = DONE; + break; + } + NEEDBITS(3); + state->last = BITS(1); + DROPBITS(1); + switch (BITS(2)) { + case 0: /* stored block */ + Tracev((stderr, "inflate: stored block%s\n", + state->last ? " (last)" : "")); + state->mode = STORED; + break; + case 1: /* fixed block */ + fixedtables(state); + Tracev((stderr, "inflate: fixed codes block%s\n", + state->last ? " (last)" : "")); + state->mode = LEN; /* decode codes */ + break; + case 2: /* dynamic block */ + Tracev((stderr, "inflate: dynamic codes block%s\n", + state->last ? " (last)" : "")); + state->mode = TABLE; + break; + case 3: + strm->msg = (char *)"invalid block type"; + state->mode = BAD; + } + DROPBITS(2); + break; + + case STORED: + /* get and verify stored block length */ + BYTEBITS(); /* go to byte boundary */ + NEEDBITS(32); + if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { + strm->msg = (char *)"invalid stored block lengths"; + state->mode = BAD; + break; + } + state->length = (unsigned)hold & 0xffff; + Tracev((stderr, "inflate: stored length %u\n", + state->length)); + INITBITS(); + + /* copy stored block from input to output */ + while (state->length != 0) { + copy = state->length; + PULL(); + ROOM(); + if (copy > have) copy = have; + if (copy > left) copy = left; + zmemcpy(put, next, copy); + have -= copy; + next += copy; + left -= copy; + put += copy; + state->length -= copy; + } + Tracev((stderr, "inflate: stored end\n")); + state->mode = TYPE; + break; + + case TABLE: + /* get dynamic table entries descriptor */ + NEEDBITS(14); + state->nlen = BITS(5) + 257; + DROPBITS(5); + state->ndist = BITS(5) + 1; + DROPBITS(5); + state->ncode = BITS(4) + 4; + DROPBITS(4); +#ifndef PKZIP_BUG_WORKAROUND + if (state->nlen > 286 || state->ndist > 30) { + strm->msg = (char *)"too many length or distance symbols"; + state->mode = BAD; + break; + } +#endif + Tracev((stderr, "inflate: table sizes ok\n")); + + /* get code length code lengths (not a typo) */ + state->have = 0; + while (state->have < state->ncode) { + NEEDBITS(3); + state->lens[order[state->have++]] = (unsigned short)BITS(3); + DROPBITS(3); + } + while (state->have < 19) + state->lens[order[state->have++]] = 0; + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 7; + ret = inflate_table(CODES, state->lens, 19, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid code lengths set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: code lengths ok\n")); + + /* get length and distance code code lengths */ + state->have = 0; + while (state->have < state->nlen + state->ndist) { + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.val < 16) { + NEEDBITS(this.bits); + DROPBITS(this.bits); + state->lens[state->have++] = this.val; + } + else { + if (this.val == 16) { + NEEDBITS(this.bits + 2); + DROPBITS(this.bits); + if (state->have == 0) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + len = (unsigned)(state->lens[state->have - 1]); + copy = 3 + BITS(2); + DROPBITS(2); + } + else if (this.val == 17) { + NEEDBITS(this.bits + 3); + DROPBITS(this.bits); + len = 0; + copy = 3 + BITS(3); + DROPBITS(3); + } + else { + NEEDBITS(this.bits + 7); + DROPBITS(this.bits); + len = 0; + copy = 11 + BITS(7); + DROPBITS(7); + } + if (state->have + copy > state->nlen + state->ndist) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + while (copy--) + state->lens[state->have++] = (unsigned short)len; + } + } + + /* handle error breaks in while */ + if (state->mode == BAD) break; + + /* build code tables */ + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 9; + ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid literal/lengths set"; + state->mode = BAD; + break; + } + state->distcode = (code const FAR *)(state->next); + state->distbits = 6; + ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, + &(state->next), &(state->distbits), state->work); + if (ret) { + strm->msg = (char *)"invalid distances set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: codes ok\n")); + state->mode = LEN; + + case LEN: + /* use inflate_fast() if we have enough input and output */ + if (have >= 6 && left >= 258) { + RESTORE(); + if (state->whave < state->wsize) + state->whave = state->wsize - left; + inflate_fast(strm, state->wsize); + LOAD(); + break; + } + + /* get a literal, length, or end-of-block code */ + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.op && (this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->lencode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + state->length = (unsigned)this.val; + + /* process literal */ + if (this.op == 0) { + Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", this.val)); + ROOM(); + *put++ = (unsigned char)(state->length); + left--; + state->mode = LEN; + break; + } + + /* process end of block */ + if (this.op & 32) { + Tracevv((stderr, "inflate: end of block\n")); + state->mode = TYPE; + break; + } + + /* invalid code */ + if (this.op & 64) { + strm->msg = (char *)"invalid literal/length code"; + state->mode = BAD; + break; + } + + /* length code -- get extra bits, if any */ + state->extra = (unsigned)(this.op) & 15; + if (state->extra != 0) { + NEEDBITS(state->extra); + state->length += BITS(state->extra); + DROPBITS(state->extra); + } + Tracevv((stderr, "inflate: length %u\n", state->length)); + + /* get distance code */ + for (;;) { + this = state->distcode[BITS(state->distbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if ((this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->distcode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + if (this.op & 64) { + strm->msg = (char *)"invalid distance code"; + state->mode = BAD; + break; + } + state->offset = (unsigned)this.val; + + /* get distance extra bits, if any */ + state->extra = (unsigned)(this.op) & 15; + if (state->extra != 0) { + NEEDBITS(state->extra); + state->offset += BITS(state->extra); + DROPBITS(state->extra); + } + if (state->offset > state->wsize - (state->whave < state->wsize ? + left : 0)) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } + Tracevv((stderr, "inflate: distance %u\n", state->offset)); + + /* copy match from window to output */ + do { + ROOM(); + copy = state->wsize - state->offset; + if (copy < left) { + from = put + copy; + copy = left - copy; + } + else { + from = put - state->offset; + copy = left; + } + if (copy > state->length) copy = state->length; + state->length -= copy; + left -= copy; + do { + *put++ = *from++; + } while (--copy); + } while (state->length != 0); + break; + + case DONE: + /* inflate stream terminated properly -- write leftover output */ + ret = Z_STREAM_END; + if (left < state->wsize) { + if (out(out_desc, state->window, state->wsize - left)) + ret = Z_BUF_ERROR; + } + goto inf_leave; + + case BAD: + ret = Z_DATA_ERROR; + goto inf_leave; + + default: /* can't happen, but makes compilers happy */ + ret = Z_STREAM_ERROR; + goto inf_leave; + } + + /* Return unused input */ + inf_leave: + strm->next_in = next; + strm->avail_in = have; + return ret; +} + +int ZEXPORT inflateBackEnd(strm) +z_streamp strm; +{ + if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) + return Z_STREAM_ERROR; + ZFREE(strm, strm->state); + strm->state = Z_NULL; + Tracev((stderr, "inflate: end\n")); + return Z_OK; +} diff --git a/cbits/inffast.c b/cbits/inffast.c new file mode 100644 --- /dev/null +++ b/cbits/inffast.c @@ -0,0 +1,318 @@ +/* inffast.c -- fast decoding + * Copyright (C) 1995-2004 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "zutil.h" +#include "inftrees.h" +#include "inflate.h" +#include "inffast.h" + +#ifndef ASMINF + +/* Allow machine dependent optimization for post-increment or pre-increment. + Based on testing to date, + Pre-increment preferred for: + - PowerPC G3 (Adler) + - MIPS R5000 (Randers-Pehrson) + Post-increment preferred for: + - none + No measurable difference: + - Pentium III (Anderson) + - M68060 (Nikl) + */ +#ifdef POSTINC +# define OFF 0 +# define PUP(a) *(a)++ +#else +# define OFF 1 +# define PUP(a) *++(a) +#endif + +/* + Decode literal, length, and distance codes and write out the resulting + literal and match bytes until either not enough input or output is + available, an end-of-block is encountered, or a data error is encountered. + When large enough input and output buffers are supplied to inflate(), for + example, a 16K input buffer and a 64K output buffer, more than 95% of the + inflate execution time is spent in this routine. + + Entry assumptions: + + state->mode == LEN + strm->avail_in >= 6 + strm->avail_out >= 258 + start >= strm->avail_out + state->bits < 8 + + On return, state->mode is one of: + + LEN -- ran out of enough output space or enough available input + TYPE -- reached end of block code, inflate() to interpret next block + BAD -- error in block data + + Notes: + + - The maximum input bits used by a length/distance pair is 15 bits for the + length code, 5 bits for the length extra, 15 bits for the distance code, + and 13 bits for the distance extra. This totals 48 bits, or six bytes. + Therefore if strm->avail_in >= 6, then there is enough input to avoid + checking for available input while decoding. + + - The maximum bytes that a single length/distance pair can output is 258 + bytes, which is the maximum length that can be coded. inflate_fast() + requires strm->avail_out >= 258 for each loop to avoid checking for + output space. + */ +void inflate_fast(strm, start) +z_streamp strm; +unsigned start; /* inflate()'s starting value for strm->avail_out */ +{ + struct inflate_state FAR *state; + unsigned char FAR *in; /* local strm->next_in */ + unsigned char FAR *last; /* while in < last, enough input available */ + unsigned char FAR *out; /* local strm->next_out */ + unsigned char FAR *beg; /* inflate()'s initial strm->next_out */ + unsigned char FAR *end; /* while out < end, enough space available */ +#ifdef INFLATE_STRICT + unsigned dmax; /* maximum distance from zlib header */ +#endif + unsigned wsize; /* window size or zero if not using window */ + unsigned whave; /* valid bytes in the window */ + unsigned write; /* window write index */ + unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ + unsigned long hold; /* local strm->hold */ + unsigned bits; /* local strm->bits */ + code const FAR *lcode; /* local strm->lencode */ + code const FAR *dcode; /* local strm->distcode */ + unsigned lmask; /* mask for first level of length codes */ + unsigned dmask; /* mask for first level of distance codes */ + code this; /* retrieved table entry */ + unsigned op; /* code bits, operation, extra bits, or */ + /* window position, window bytes to copy */ + unsigned len; /* match length, unused bytes */ + unsigned dist; /* match distance */ + unsigned char FAR *from; /* where to copy match from */ + + /* copy state to local variables */ + state = (struct inflate_state FAR *)strm->state; + in = strm->next_in - OFF; + last = in + (strm->avail_in - 5); + out = strm->next_out - OFF; + beg = out - (start - strm->avail_out); + end = out + (strm->avail_out - 257); +#ifdef INFLATE_STRICT + dmax = state->dmax; +#endif + wsize = state->wsize; + whave = state->whave; + write = state->write; + window = state->window; + hold = state->hold; + bits = state->bits; + lcode = state->lencode; + dcode = state->distcode; + lmask = (1U << state->lenbits) - 1; + dmask = (1U << state->distbits) - 1; + + /* decode literals and length/distances until end-of-block or not enough + input data or output space */ + do { + if (bits < 15) { + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + } + this = lcode[hold & lmask]; + dolen: + op = (unsigned)(this.bits); + hold >>= op; + bits -= op; + op = (unsigned)(this.op); + if (op == 0) { /* literal */ + Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", this.val)); + PUP(out) = (unsigned char)(this.val); + } + else if (op & 16) { /* length base */ + len = (unsigned)(this.val); + op &= 15; /* number of extra bits */ + if (op) { + if (bits < op) { + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + } + len += (unsigned)hold & ((1U << op) - 1); + hold >>= op; + bits -= op; + } + Tracevv((stderr, "inflate: length %u\n", len)); + if (bits < 15) { + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + } + this = dcode[hold & dmask]; + dodist: + op = (unsigned)(this.bits); + hold >>= op; + bits -= op; + op = (unsigned)(this.op); + if (op & 16) { /* distance base */ + dist = (unsigned)(this.val); + op &= 15; /* number of extra bits */ + if (bits < op) { + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + if (bits < op) { + hold += (unsigned long)(PUP(in)) << bits; + bits += 8; + } + } + dist += (unsigned)hold & ((1U << op) - 1); +#ifdef INFLATE_STRICT + if (dist > dmax) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#endif + hold >>= op; + bits -= op; + Tracevv((stderr, "inflate: distance %u\n", dist)); + op = (unsigned)(out - beg); /* max distance in output */ + if (dist > op) { /* see if copy from window */ + op = dist - op; /* distance back in window */ + if (op > whave) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } + from = window - OFF; + if (write == 0) { /* very common case */ + from += wsize - op; + if (op < len) { /* some from window */ + len -= op; + do { + PUP(out) = PUP(from); + } while (--op); + from = out - dist; /* rest from output */ + } + } + else if (write < op) { /* wrap around window */ + from += wsize + write - op; + op -= write; + if (op < len) { /* some from end of window */ + len -= op; + do { + PUP(out) = PUP(from); + } while (--op); + from = window - OFF; + if (write < len) { /* some from start of window */ + op = write; + len -= op; + do { + PUP(out) = PUP(from); + } while (--op); + from = out - dist; /* rest from output */ + } + } + } + else { /* contiguous in window */ + from += write - op; + if (op < len) { /* some from window */ + len -= op; + do { + PUP(out) = PUP(from); + } while (--op); + from = out - dist; /* rest from output */ + } + } + while (len > 2) { + PUP(out) = PUP(from); + PUP(out) = PUP(from); + PUP(out) = PUP(from); + len -= 3; + } + if (len) { + PUP(out) = PUP(from); + if (len > 1) + PUP(out) = PUP(from); + } + } + else { + from = out - dist; /* copy direct from output */ + do { /* minimum length is three */ + PUP(out) = PUP(from); + PUP(out) = PUP(from); + PUP(out) = PUP(from); + len -= 3; + } while (len > 2); + if (len) { + PUP(out) = PUP(from); + if (len > 1) + PUP(out) = PUP(from); + } + } + } + else if ((op & 64) == 0) { /* 2nd level distance code */ + this = dcode[this.val + (hold & ((1U << op) - 1))]; + goto dodist; + } + else { + strm->msg = (char *)"invalid distance code"; + state->mode = BAD; + break; + } + } + else if ((op & 64) == 0) { /* 2nd level length code */ + this = lcode[this.val + (hold & ((1U << op) - 1))]; + goto dolen; + } + else if (op & 32) { /* end-of-block */ + Tracevv((stderr, "inflate: end of block\n")); + state->mode = TYPE; + break; + } + else { + strm->msg = (char *)"invalid literal/length code"; + state->mode = BAD; + break; + } + } while (in < last && out < end); + + /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ + len = bits >> 3; + in -= len; + bits -= len << 3; + hold &= (1U << bits) - 1; + + /* update state and return */ + strm->next_in = in + OFF; + strm->next_out = out + OFF; + strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last)); + strm->avail_out = (unsigned)(out < end ? + 257 + (end - out) : 257 - (out - end)); + state->hold = hold; + state->bits = bits; + return; +} + +/* + inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe): + - Using bit fields for code structure + - Different op definition to avoid & for extra bits (do & for table bits) + - Three separate decoding do-loops for direct, window, and write == 0 + - Special case for distance > 1 copies to do overlapped load and store copy + - Explicit branch predictions (based on measured branch probabilities) + - Deferring match copy and interspersed it with decoding subsequent codes + - Swapping literal/length else + - Swapping window/direct else + - Larger unrolled copy loops (three is about right) + - Moving len -= 3 statement into middle of loop + */ + +#endif /* !ASMINF */ diff --git a/cbits/inflate.c b/cbits/inflate.c new file mode 100644 --- /dev/null +++ b/cbits/inflate.c @@ -0,0 +1,1368 @@ +/* inflate.c -- zlib decompression + * Copyright (C) 1995-2005 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * Change history: + * + * 1.2.beta0 24 Nov 2002 + * - First version -- complete rewrite of inflate to simplify code, avoid + * creation of window when not needed, minimize use of window when it is + * needed, make inffast.c even faster, implement gzip decoding, and to + * improve code readability and style over the previous zlib inflate code + * + * 1.2.beta1 25 Nov 2002 + * - Use pointers for available input and output checking in inffast.c + * - Remove input and output counters in inffast.c + * - Change inffast.c entry and loop from avail_in >= 7 to >= 6 + * - Remove unnecessary second byte pull from length extra in inffast.c + * - Unroll direct copy to three copies per loop in inffast.c + * + * 1.2.beta2 4 Dec 2002 + * - Change external routine names to reduce potential conflicts + * - Correct filename to inffixed.h for fixed tables in inflate.c + * - Make hbuf[] unsigned char to match parameter type in inflate.c + * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset) + * to avoid negation problem on Alphas (64 bit) in inflate.c + * + * 1.2.beta3 22 Dec 2002 + * - Add comments on state->bits assertion in inffast.c + * - Add comments on op field in inftrees.h + * - Fix bug in reuse of allocated window after inflateReset() + * - Remove bit fields--back to byte structure for speed + * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths + * - Change post-increments to pre-increments in inflate_fast(), PPC biased? + * - Add compile time option, POSTINC, to use post-increments instead (Intel?) + * - Make MATCH copy in inflate() much faster for when inflate_fast() not used + * - Use local copies of stream next and avail values, as well as local bit + * buffer and bit count in inflate()--for speed when inflate_fast() not used + * + * 1.2.beta4 1 Jan 2003 + * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings + * - Move a comment on output buffer sizes from inffast.c to inflate.c + * - Add comments in inffast.c to introduce the inflate_fast() routine + * - Rearrange window copies in inflate_fast() for speed and simplification + * - Unroll last copy for window match in inflate_fast() + * - Use local copies of window variables in inflate_fast() for speed + * - Pull out common write == 0 case for speed in inflate_fast() + * - Make op and len in inflate_fast() unsigned for consistency + * - Add FAR to lcode and dcode declarations in inflate_fast() + * - Simplified bad distance check in inflate_fast() + * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new + * source file infback.c to provide a call-back interface to inflate for + * programs like gzip and unzip -- uses window as output buffer to avoid + * window copying + * + * 1.2.beta5 1 Jan 2003 + * - Improved inflateBack() interface to allow the caller to provide initial + * input in strm. + * - Fixed stored blocks bug in inflateBack() + * + * 1.2.beta6 4 Jan 2003 + * - Added comments in inffast.c on effectiveness of POSTINC + * - Typecasting all around to reduce compiler warnings + * - Changed loops from while (1) or do {} while (1) to for (;;), again to + * make compilers happy + * - Changed type of window in inflateBackInit() to unsigned char * + * + * 1.2.beta7 27 Jan 2003 + * - Changed many types to unsigned or unsigned short to avoid warnings + * - Added inflateCopy() function + * + * 1.2.0 9 Mar 2003 + * - Changed inflateBack() interface to provide separate opaque descriptors + * for the in() and out() functions + * - Changed inflateBack() argument and in_func typedef to swap the length + * and buffer address return values for the input function + * - Check next_in and next_out for Z_NULL on entry to inflate() + * + * The history for versions after 1.2.0 are in ChangeLog in zlib distribution. + */ + +#include "zutil.h" +#include "inftrees.h" +#include "inflate.h" +#include "inffast.h" + +#ifdef MAKEFIXED +# ifndef BUILDFIXED +# define BUILDFIXED +# endif +#endif + +/* function prototypes */ +local void fixedtables OF((struct inflate_state FAR *state)); +local int updatewindow OF((z_streamp strm, unsigned out)); +#ifdef BUILDFIXED + void makefixed OF((void)); +#endif +local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf, + unsigned len)); + +int ZEXPORT inflateReset(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + strm->total_in = strm->total_out = state->total = 0; + strm->msg = Z_NULL; + strm->adler = 1; /* to support ill-conceived Java test suite */ + state->mode = HEAD; + state->last = 0; + state->havedict = 0; + state->dmax = 32768U; + state->head = Z_NULL; + state->wsize = 0; + state->whave = 0; + state->write = 0; + state->hold = 0; + state->bits = 0; + state->lencode = state->distcode = state->next = state->codes; + Tracev((stderr, "inflate: reset\n")); + return Z_OK; +} + +int ZEXPORT inflatePrime(strm, bits, value) +z_streamp strm; +int bits; +int value; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR; + value &= (1L << bits) - 1; + state->hold += value << state->bits; + state->bits += bits; + return Z_OK; +} + +int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) +z_streamp strm; +int windowBits; +const char *version; +int stream_size; +{ + struct inflate_state FAR *state; + + if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || + stream_size != (int)(sizeof(z_stream))) + return Z_VERSION_ERROR; + if (strm == Z_NULL) return Z_STREAM_ERROR; + strm->msg = Z_NULL; /* in case we return an error */ + if (strm->zalloc == (alloc_func)0) { + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; + } + if (strm->zfree == (free_func)0) strm->zfree = zcfree; + state = (struct inflate_state FAR *) + ZALLOC(strm, 1, sizeof(struct inflate_state)); + if (state == Z_NULL) return Z_MEM_ERROR; + Tracev((stderr, "inflate: allocated\n")); + strm->state = (struct internal_state FAR *)state; + if (windowBits < 0) { + state->wrap = 0; + windowBits = -windowBits; + } + else { + state->wrap = (windowBits >> 4) + 1; +#ifdef GUNZIP + if (windowBits < 48) windowBits &= 15; +#endif + } + if (windowBits < 8 || windowBits > 15) { + ZFREE(strm, state); + strm->state = Z_NULL; + return Z_STREAM_ERROR; + } + state->wbits = (unsigned)windowBits; + state->window = Z_NULL; + return inflateReset(strm); +} + +int ZEXPORT inflateInit_(strm, version, stream_size) +z_streamp strm; +const char *version; +int stream_size; +{ + return inflateInit2_(strm, DEF_WBITS, version, stream_size); +} + +/* + Return state with length and distance decoding tables and index sizes set to + fixed code decoding. Normally this returns fixed tables from inffixed.h. + If BUILDFIXED is defined, then instead this routine builds the tables the + first time it's called, and returns those tables the first time and + thereafter. This reduces the size of the code by about 2K bytes, in + exchange for a little execution time. However, BUILDFIXED should not be + used for threaded applications, since the rewriting of the tables and virgin + may not be thread-safe. + */ +local void fixedtables(state) +struct inflate_state FAR *state; +{ +#ifdef BUILDFIXED + static int virgin = 1; + static code *lenfix, *distfix; + static code fixed[544]; + + /* build fixed huffman tables if first call (may not be thread safe) */ + if (virgin) { + unsigned sym, bits; + static code *next; + + /* literal/length table */ + sym = 0; + while (sym < 144) state->lens[sym++] = 8; + while (sym < 256) state->lens[sym++] = 9; + while (sym < 280) state->lens[sym++] = 7; + while (sym < 288) state->lens[sym++] = 8; + next = fixed; + lenfix = next; + bits = 9; + inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); + + /* distance table */ + sym = 0; + while (sym < 32) state->lens[sym++] = 5; + distfix = next; + bits = 5; + inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); + + /* do this just once */ + virgin = 0; + } +#else /* !BUILDFIXED */ +# include "inffixed.h" +#endif /* BUILDFIXED */ + state->lencode = lenfix; + state->lenbits = 9; + state->distcode = distfix; + state->distbits = 5; +} + +#ifdef MAKEFIXED +#include + +/* + Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also + defines BUILDFIXED, so the tables are built on the fly. makefixed() writes + those tables to stdout, which would be piped to inffixed.h. A small program + can simply call makefixed to do this: + + void makefixed(void); + + int main(void) + { + makefixed(); + return 0; + } + + Then that can be linked with zlib built with MAKEFIXED defined and run: + + a.out > inffixed.h + */ +void makefixed() +{ + unsigned low, size; + struct inflate_state state; + + fixedtables(&state); + puts(" /* inffixed.h -- table for decoding fixed codes"); + puts(" * Generated automatically by makefixed()."); + puts(" */"); + puts(""); + puts(" /* WARNING: this file should *not* be used by applications."); + puts(" It is part of the implementation of this library and is"); + puts(" subject to change. Applications should only use zlib.h."); + puts(" */"); + puts(""); + size = 1U << 9; + printf(" static const code lenfix[%u] = {", size); + low = 0; + for (;;) { + if ((low % 7) == 0) printf("\n "); + printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits, + state.lencode[low].val); + if (++low == size) break; + putchar(','); + } + puts("\n };"); + size = 1U << 5; + printf("\n static const code distfix[%u] = {", size); + low = 0; + for (;;) { + if ((low % 6) == 0) printf("\n "); + printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits, + state.distcode[low].val); + if (++low == size) break; + putchar(','); + } + puts("\n };"); +} +#endif /* MAKEFIXED */ + +/* + Update the window with the last wsize (normally 32K) bytes written before + returning. If window does not exist yet, create it. This is only called + when a window is already in use, or when output has been written during this + inflate call, but the end of the deflate stream has not been reached yet. + It is also called to create a window for dictionary data when a dictionary + is loaded. + + Providing output buffers larger than 32K to inflate() should provide a speed + advantage, since only the last 32K of output is copied to the sliding window + upon return from inflate(), and since all distances after the first 32K of + output will fall in the output data, making match copies simpler and faster. + The advantage may be dependent on the size of the processor's data caches. + */ +local int updatewindow(strm, out) +z_streamp strm; +unsigned out; +{ + struct inflate_state FAR *state; + unsigned copy, dist; + + state = (struct inflate_state FAR *)strm->state; + + /* if it hasn't been done already, allocate space for the window */ + if (state->window == Z_NULL) { + state->window = (unsigned char FAR *) + ZALLOC(strm, 1U << state->wbits, + sizeof(unsigned char)); + if (state->window == Z_NULL) return 1; + } + + /* if window not in use yet, initialize */ + if (state->wsize == 0) { + state->wsize = 1U << state->wbits; + state->write = 0; + state->whave = 0; + } + + /* copy state->wsize or less output bytes into the circular window */ + copy = out - strm->avail_out; + if (copy >= state->wsize) { + zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); + state->write = 0; + state->whave = state->wsize; + } + else { + dist = state->wsize - state->write; + if (dist > copy) dist = copy; + zmemcpy(state->window + state->write, strm->next_out - copy, dist); + copy -= dist; + if (copy) { + zmemcpy(state->window, strm->next_out - copy, copy); + state->write = copy; + state->whave = state->wsize; + } + else { + state->write += dist; + if (state->write == state->wsize) state->write = 0; + if (state->whave < state->wsize) state->whave += dist; + } + } + return 0; +} + +/* Macros for inflate(): */ + +/* check function to use adler32() for zlib or crc32() for gzip */ +#ifdef GUNZIP +# define UPDATE(check, buf, len) \ + (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) +#else +# define UPDATE(check, buf, len) adler32(check, buf, len) +#endif + +/* check macros for header crc */ +#ifdef GUNZIP +# define CRC2(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + check = crc32(check, hbuf, 2); \ + } while (0) + +# define CRC4(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + hbuf[2] = (unsigned char)((word) >> 16); \ + hbuf[3] = (unsigned char)((word) >> 24); \ + check = crc32(check, hbuf, 4); \ + } while (0) +#endif + +/* Load registers with state in inflate() for speed */ +#define LOAD() \ + do { \ + put = strm->next_out; \ + left = strm->avail_out; \ + next = strm->next_in; \ + have = strm->avail_in; \ + hold = state->hold; \ + bits = state->bits; \ + } while (0) + +/* Restore state from registers in inflate() */ +#define RESTORE() \ + do { \ + strm->next_out = put; \ + strm->avail_out = left; \ + strm->next_in = next; \ + strm->avail_in = have; \ + state->hold = hold; \ + state->bits = bits; \ + } while (0) + +/* Clear the input bit accumulator */ +#define INITBITS() \ + do { \ + hold = 0; \ + bits = 0; \ + } while (0) + +/* Get a byte of input into the bit accumulator, or return from inflate() + if there is no input available. */ +#define PULLBYTE() \ + do { \ + if (have == 0) goto inf_leave; \ + have--; \ + hold += (unsigned long)(*next++) << bits; \ + bits += 8; \ + } while (0) + +/* Assure that there are at least n bits in the bit accumulator. If there is + not enough available input to do that, then return from inflate(). */ +#define NEEDBITS(n) \ + do { \ + while (bits < (unsigned)(n)) \ + PULLBYTE(); \ + } while (0) + +/* Return the low n bits of the bit accumulator (n < 16) */ +#define BITS(n) \ + ((unsigned)hold & ((1U << (n)) - 1)) + +/* Remove n bits from the bit accumulator */ +#define DROPBITS(n) \ + do { \ + hold >>= (n); \ + bits -= (unsigned)(n); \ + } while (0) + +/* Remove zero to seven bits as needed to go to a byte boundary */ +#define BYTEBITS() \ + do { \ + hold >>= bits & 7; \ + bits -= bits & 7; \ + } while (0) + +/* Reverse the bytes in a 32-bit value */ +#define REVERSE(q) \ + ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \ + (((q) & 0xff00) << 8) + (((q) & 0xff) << 24)) + +/* + inflate() uses a state machine to process as much input data and generate as + much output data as possible before returning. The state machine is + structured roughly as follows: + + for (;;) switch (state) { + ... + case STATEn: + if (not enough input data or output space to make progress) + return; + ... make progress ... + state = STATEm; + break; + ... + } + + so when inflate() is called again, the same case is attempted again, and + if the appropriate resources are provided, the machine proceeds to the + next state. The NEEDBITS() macro is usually the way the state evaluates + whether it can proceed or should return. NEEDBITS() does the return if + the requested bits are not available. The typical use of the BITS macros + is: + + NEEDBITS(n); + ... do something with BITS(n) ... + DROPBITS(n); + + where NEEDBITS(n) either returns from inflate() if there isn't enough + input left to load n bits into the accumulator, or it continues. BITS(n) + gives the low n bits in the accumulator. When done, DROPBITS(n) drops + the low n bits off the accumulator. INITBITS() clears the accumulator + and sets the number of available bits to zero. BYTEBITS() discards just + enough bits to put the accumulator on a byte boundary. After BYTEBITS() + and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. + + NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return + if there is no input available. The decoding of variable length codes uses + PULLBYTE() directly in order to pull just enough bytes to decode the next + code, and no more. + + Some states loop until they get enough input, making sure that enough + state information is maintained to continue the loop where it left off + if NEEDBITS() returns in the loop. For example, want, need, and keep + would all have to actually be part of the saved state in case NEEDBITS() + returns: + + case STATEw: + while (want < need) { + NEEDBITS(n); + keep[want++] = BITS(n); + DROPBITS(n); + } + state = STATEx; + case STATEx: + + As shown above, if the next state is also the next case, then the break + is omitted. + + A state may also return if there is not enough output space available to + complete that state. Those states are copying stored data, writing a + literal byte, and copying a matching string. + + When returning, a "goto inf_leave" is used to update the total counters, + update the check value, and determine whether any progress has been made + during that inflate() call in order to return the proper return code. + Progress is defined as a change in either strm->avail_in or strm->avail_out. + When there is a window, goto inf_leave will update the window with the last + output written. If a goto inf_leave occurs in the middle of decompression + and there is no window currently, goto inf_leave will create one and copy + output to the window for the next call of inflate(). + + In this implementation, the flush parameter of inflate() only affects the + return code (per zlib.h). inflate() always writes as much as possible to + strm->next_out, given the space available and the provided input--the effect + documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers + the allocation of and copying into a sliding window until necessary, which + provides the effect documented in zlib.h for Z_FINISH when the entire input + stream available. So the only thing the flush parameter actually does is: + when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it + will return Z_BUF_ERROR if it has not reached the end of the stream. + */ + +int ZEXPORT inflate(strm, flush) +z_streamp strm; +int flush; +{ + struct inflate_state FAR *state; + unsigned char FAR *next; /* next input */ + unsigned char FAR *put; /* next output */ + unsigned have, left; /* available input and output */ + unsigned long hold; /* bit buffer */ + unsigned bits; /* bits in bit buffer */ + unsigned in, out; /* save starting available input and output */ + unsigned copy; /* number of stored or match bytes to copy */ + unsigned char FAR *from; /* where to copy match bytes from */ + code this; /* current decoding table entry */ + code last; /* parent table entry */ + unsigned len; /* length to copy for repeats, bits to drop */ + int ret; /* return code */ +#ifdef GUNZIP + unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ +#endif + static const unsigned short order[19] = /* permutation of code lengths */ + {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + + if (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL || + (strm->next_in == Z_NULL && strm->avail_in != 0)) + return Z_STREAM_ERROR; + + state = (struct inflate_state FAR *)strm->state; + if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ + LOAD(); + in = have; + out = left; + ret = Z_OK; + for (;;) + switch (state->mode) { + case HEAD: + if (state->wrap == 0) { + state->mode = TYPEDO; + break; + } + NEEDBITS(16); +#ifdef GUNZIP + if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ + state->check = crc32(0L, Z_NULL, 0); + CRC2(state->check, hold); + INITBITS(); + state->mode = FLAGS; + break; + } + state->flags = 0; /* expect zlib header */ + if (state->head != Z_NULL) + state->head->done = -1; + if (!(state->wrap & 1) || /* check if zlib header allowed */ +#else + if ( +#endif + ((BITS(8) << 8) + (hold >> 8)) % 31) { + strm->msg = (char *)"incorrect header check"; + state->mode = BAD; + break; + } + if (BITS(4) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + DROPBITS(4); + len = BITS(4) + 8; + if (len > state->wbits) { + strm->msg = (char *)"invalid window size"; + state->mode = BAD; + break; + } + state->dmax = 1U << len; + Tracev((stderr, "inflate: zlib header ok\n")); + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = hold & 0x200 ? DICTID : TYPE; + INITBITS(); + break; +#ifdef GUNZIP + case FLAGS: + NEEDBITS(16); + state->flags = (int)(hold); + if ((state->flags & 0xff) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + if (state->flags & 0xe000) { + strm->msg = (char *)"unknown header flags set"; + state->mode = BAD; + break; + } + if (state->head != Z_NULL) + state->head->text = (int)((hold >> 8) & 1); + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + state->mode = TIME; + case TIME: + NEEDBITS(32); + if (state->head != Z_NULL) + state->head->time = hold; + if (state->flags & 0x0200) CRC4(state->check, hold); + INITBITS(); + state->mode = OS; + case OS: + NEEDBITS(16); + if (state->head != Z_NULL) { + state->head->xflags = (int)(hold & 0xff); + state->head->os = (int)(hold >> 8); + } + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + state->mode = EXLEN; + case EXLEN: + if (state->flags & 0x0400) { + NEEDBITS(16); + state->length = (unsigned)(hold); + if (state->head != Z_NULL) + state->head->extra_len = (unsigned)hold; + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + } + else if (state->head != Z_NULL) + state->head->extra = Z_NULL; + state->mode = EXTRA; + case EXTRA: + if (state->flags & 0x0400) { + copy = state->length; + if (copy > have) copy = have; + if (copy) { + if (state->head != Z_NULL && + state->head->extra != Z_NULL) { + len = state->head->extra_len - state->length; + zmemcpy(state->head->extra + len, next, + len + copy > state->head->extra_max ? + state->head->extra_max - len : copy); + } + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + state->length -= copy; + } + if (state->length) goto inf_leave; + } + state->length = 0; + state->mode = NAME; + case NAME: + if (state->flags & 0x0800) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->name != Z_NULL && + state->length < state->head->name_max) + state->head->name[state->length++] = len; + } while (len && copy < have); + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->name = Z_NULL; + state->length = 0; + state->mode = COMMENT; + case COMMENT: + if (state->flags & 0x1000) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->comment != Z_NULL && + state->length < state->head->comm_max) + state->head->comment[state->length++] = len; + } while (len && copy < have); + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->comment = Z_NULL; + state->mode = HCRC; + case HCRC: + if (state->flags & 0x0200) { + NEEDBITS(16); + if (hold != (state->check & 0xffff)) { + strm->msg = (char *)"header crc mismatch"; + state->mode = BAD; + break; + } + INITBITS(); + } + if (state->head != Z_NULL) { + state->head->hcrc = (int)((state->flags >> 9) & 1); + state->head->done = 1; + } + strm->adler = state->check = crc32(0L, Z_NULL, 0); + state->mode = TYPE; + break; +#endif + case DICTID: + NEEDBITS(32); + strm->adler = state->check = REVERSE(hold); + INITBITS(); + state->mode = DICT; + case DICT: + if (state->havedict == 0) { + RESTORE(); + return Z_NEED_DICT; + } + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = TYPE; + case TYPE: + if (flush == Z_BLOCK) goto inf_leave; + case TYPEDO: + if (state->last) { + BYTEBITS(); + state->mode = CHECK; + break; + } + NEEDBITS(3); + state->last = BITS(1); + DROPBITS(1); + switch (BITS(2)) { + case 0: /* stored block */ + Tracev((stderr, "inflate: stored block%s\n", + state->last ? " (last)" : "")); + state->mode = STORED; + break; + case 1: /* fixed block */ + fixedtables(state); + Tracev((stderr, "inflate: fixed codes block%s\n", + state->last ? " (last)" : "")); + state->mode = LEN; /* decode codes */ + break; + case 2: /* dynamic block */ + Tracev((stderr, "inflate: dynamic codes block%s\n", + state->last ? " (last)" : "")); + state->mode = TABLE; + break; + case 3: + strm->msg = (char *)"invalid block type"; + state->mode = BAD; + } + DROPBITS(2); + break; + case STORED: + BYTEBITS(); /* go to byte boundary */ + NEEDBITS(32); + if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { + strm->msg = (char *)"invalid stored block lengths"; + state->mode = BAD; + break; + } + state->length = (unsigned)hold & 0xffff; + Tracev((stderr, "inflate: stored length %u\n", + state->length)); + INITBITS(); + state->mode = COPY; + case COPY: + copy = state->length; + if (copy) { + if (copy > have) copy = have; + if (copy > left) copy = left; + if (copy == 0) goto inf_leave; + zmemcpy(put, next, copy); + have -= copy; + next += copy; + left -= copy; + put += copy; + state->length -= copy; + break; + } + Tracev((stderr, "inflate: stored end\n")); + state->mode = TYPE; + break; + case TABLE: + NEEDBITS(14); + state->nlen = BITS(5) + 257; + DROPBITS(5); + state->ndist = BITS(5) + 1; + DROPBITS(5); + state->ncode = BITS(4) + 4; + DROPBITS(4); +#ifndef PKZIP_BUG_WORKAROUND + if (state->nlen > 286 || state->ndist > 30) { + strm->msg = (char *)"too many length or distance symbols"; + state->mode = BAD; + break; + } +#endif + Tracev((stderr, "inflate: table sizes ok\n")); + state->have = 0; + state->mode = LENLENS; + case LENLENS: + while (state->have < state->ncode) { + NEEDBITS(3); + state->lens[order[state->have++]] = (unsigned short)BITS(3); + DROPBITS(3); + } + while (state->have < 19) + state->lens[order[state->have++]] = 0; + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 7; + ret = inflate_table(CODES, state->lens, 19, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid code lengths set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: code lengths ok\n")); + state->have = 0; + state->mode = CODELENS; + case CODELENS: + while (state->have < state->nlen + state->ndist) { + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.val < 16) { + NEEDBITS(this.bits); + DROPBITS(this.bits); + state->lens[state->have++] = this.val; + } + else { + if (this.val == 16) { + NEEDBITS(this.bits + 2); + DROPBITS(this.bits); + if (state->have == 0) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + len = state->lens[state->have - 1]; + copy = 3 + BITS(2); + DROPBITS(2); + } + else if (this.val == 17) { + NEEDBITS(this.bits + 3); + DROPBITS(this.bits); + len = 0; + copy = 3 + BITS(3); + DROPBITS(3); + } + else { + NEEDBITS(this.bits + 7); + DROPBITS(this.bits); + len = 0; + copy = 11 + BITS(7); + DROPBITS(7); + } + if (state->have + copy > state->nlen + state->ndist) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + while (copy--) + state->lens[state->have++] = (unsigned short)len; + } + } + + /* handle error breaks in while */ + if (state->mode == BAD) break; + + /* build code tables */ + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 9; + ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid literal/lengths set"; + state->mode = BAD; + break; + } + state->distcode = (code const FAR *)(state->next); + state->distbits = 6; + ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, + &(state->next), &(state->distbits), state->work); + if (ret) { + strm->msg = (char *)"invalid distances set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: codes ok\n")); + state->mode = LEN; + case LEN: + if (have >= 6 && left >= 258) { + RESTORE(); + inflate_fast(strm, out); + LOAD(); + break; + } + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.op && (this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->lencode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + state->length = (unsigned)this.val; + if ((int)(this.op) == 0) { + Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", this.val)); + state->mode = LIT; + break; + } + if (this.op & 32) { + Tracevv((stderr, "inflate: end of block\n")); + state->mode = TYPE; + break; + } + if (this.op & 64) { + strm->msg = (char *)"invalid literal/length code"; + state->mode = BAD; + break; + } + state->extra = (unsigned)(this.op) & 15; + state->mode = LENEXT; + case LENEXT: + if (state->extra) { + NEEDBITS(state->extra); + state->length += BITS(state->extra); + DROPBITS(state->extra); + } + Tracevv((stderr, "inflate: length %u\n", state->length)); + state->mode = DIST; + case DIST: + for (;;) { + this = state->distcode[BITS(state->distbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if ((this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->distcode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + if (this.op & 64) { + strm->msg = (char *)"invalid distance code"; + state->mode = BAD; + break; + } + state->offset = (unsigned)this.val; + state->extra = (unsigned)(this.op) & 15; + state->mode = DISTEXT; + case DISTEXT: + if (state->extra) { + NEEDBITS(state->extra); + state->offset += BITS(state->extra); + DROPBITS(state->extra); + } +#ifdef INFLATE_STRICT + if (state->offset > state->dmax) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#endif + if (state->offset > state->whave + out - left) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } + Tracevv((stderr, "inflate: distance %u\n", state->offset)); + state->mode = MATCH; + case MATCH: + if (left == 0) goto inf_leave; + copy = out - left; + if (state->offset > copy) { /* copy from window */ + copy = state->offset - copy; + if (copy > state->write) { + copy -= state->write; + from = state->window + (state->wsize - copy); + } + else + from = state->window + (state->write - copy); + if (copy > state->length) copy = state->length; + } + else { /* copy from output */ + from = put - state->offset; + copy = state->length; + } + if (copy > left) copy = left; + left -= copy; + state->length -= copy; + do { + *put++ = *from++; + } while (--copy); + if (state->length == 0) state->mode = LEN; + break; + case LIT: + if (left == 0) goto inf_leave; + *put++ = (unsigned char)(state->length); + left--; + state->mode = LEN; + break; + case CHECK: + if (state->wrap) { + NEEDBITS(32); + out -= left; + strm->total_out += out; + state->total += out; + if (out) + strm->adler = state->check = + UPDATE(state->check, put - out, out); + out = left; + if (( +#ifdef GUNZIP + state->flags ? hold : +#endif + REVERSE(hold)) != state->check) { + strm->msg = (char *)"incorrect data check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: check matches trailer\n")); + } +#ifdef GUNZIP + state->mode = LENGTH; + case LENGTH: + if (state->wrap && state->flags) { + NEEDBITS(32); + if (hold != (state->total & 0xffffffffUL)) { + strm->msg = (char *)"incorrect length check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: length matches trailer\n")); + } +#endif + state->mode = DONE; + case DONE: + ret = Z_STREAM_END; + goto inf_leave; + case BAD: + ret = Z_DATA_ERROR; + goto inf_leave; + case MEM: + return Z_MEM_ERROR; + case SYNC: + default: + return Z_STREAM_ERROR; + } + + /* + Return from inflate(), updating the total counts and the check value. + If there was no progress during the inflate() call, return a buffer + error. Call updatewindow() to create and/or update the window state. + Note: a memory error from inflate() is non-recoverable. + */ + inf_leave: + RESTORE(); + if (state->wsize || (state->mode < CHECK && out != strm->avail_out)) + if (updatewindow(strm, out)) { + state->mode = MEM; + return Z_MEM_ERROR; + } + in -= strm->avail_in; + out -= strm->avail_out; + strm->total_in += in; + strm->total_out += out; + state->total += out; + if (state->wrap && out) + strm->adler = state->check = + UPDATE(state->check, strm->next_out - out, out); + strm->data_type = state->bits + (state->last ? 64 : 0) + + (state->mode == TYPE ? 128 : 0); + if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) + ret = Z_BUF_ERROR; + return ret; +} + +int ZEXPORT inflateEnd(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (state->window != Z_NULL) ZFREE(strm, state->window); + ZFREE(strm, strm->state); + strm->state = Z_NULL; + Tracev((stderr, "inflate: end\n")); + return Z_OK; +} + +int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength) +z_streamp strm; +const Bytef *dictionary; +uInt dictLength; +{ + struct inflate_state FAR *state; + unsigned long id; + + /* check state */ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (state->wrap != 0 && state->mode != DICT) + return Z_STREAM_ERROR; + + /* check for correct dictionary id */ + if (state->mode == DICT) { + id = adler32(0L, Z_NULL, 0); + id = adler32(id, dictionary, dictLength); + if (id != state->check) + return Z_DATA_ERROR; + } + + /* copy dictionary to window */ + if (updatewindow(strm, strm->avail_out)) { + state->mode = MEM; + return Z_MEM_ERROR; + } + if (dictLength > state->wsize) { + zmemcpy(state->window, dictionary + dictLength - state->wsize, + state->wsize); + state->whave = state->wsize; + } + else { + zmemcpy(state->window + state->wsize - dictLength, dictionary, + dictLength); + state->whave = dictLength; + } + state->havedict = 1; + Tracev((stderr, "inflate: dictionary set\n")); + return Z_OK; +} + +int ZEXPORT inflateGetHeader(strm, head) +z_streamp strm; +gz_headerp head; +{ + struct inflate_state FAR *state; + + /* check state */ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if ((state->wrap & 2) == 0) return Z_STREAM_ERROR; + + /* save header structure */ + state->head = head; + head->done = 0; + return Z_OK; +} + +/* + Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found + or when out of input. When called, *have is the number of pattern bytes + found in order so far, in 0..3. On return *have is updated to the new + state. If on return *have equals four, then the pattern was found and the + return value is how many bytes were read including the last byte of the + pattern. If *have is less than four, then the pattern has not been found + yet and the return value is len. In the latter case, syncsearch() can be + called again with more data and the *have state. *have is initialized to + zero for the first call. + */ +local unsigned syncsearch(have, buf, len) +unsigned FAR *have; +unsigned char FAR *buf; +unsigned len; +{ + unsigned got; + unsigned next; + + got = *have; + next = 0; + while (next < len && got < 4) { + if ((int)(buf[next]) == (got < 2 ? 0 : 0xff)) + got++; + else if (buf[next]) + got = 0; + else + got = 4 - got; + next++; + } + *have = got; + return next; +} + +int ZEXPORT inflateSync(strm) +z_streamp strm; +{ + unsigned len; /* number of bytes to look at or looked at */ + unsigned long in, out; /* temporary to save total_in and total_out */ + unsigned char buf[4]; /* to restore bit buffer to byte string */ + struct inflate_state FAR *state; + + /* check parameters */ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR; + + /* if first time, start search in bit buffer */ + if (state->mode != SYNC) { + state->mode = SYNC; + state->hold <<= state->bits & 7; + state->bits -= state->bits & 7; + len = 0; + while (state->bits >= 8) { + buf[len++] = (unsigned char)(state->hold); + state->hold >>= 8; + state->bits -= 8; + } + state->have = 0; + syncsearch(&(state->have), buf, len); + } + + /* search available input */ + len = syncsearch(&(state->have), strm->next_in, strm->avail_in); + strm->avail_in -= len; + strm->next_in += len; + strm->total_in += len; + + /* return no joy or set up to restart inflate() on a new block */ + if (state->have != 4) return Z_DATA_ERROR; + in = strm->total_in; out = strm->total_out; + inflateReset(strm); + strm->total_in = in; strm->total_out = out; + state->mode = TYPE; + return Z_OK; +} + +/* + Returns true if inflate is currently at the end of a block generated by + Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP + implementation to provide an additional safety check. PPP uses + Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored + block. When decompressing, PPP checks that at the end of input packet, + inflate is waiting for these length bytes. + */ +int ZEXPORT inflateSyncPoint(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + return state->mode == STORED && state->bits == 0; +} + +int ZEXPORT inflateCopy(dest, source) +z_streamp dest; +z_streamp source; +{ + struct inflate_state FAR *state; + struct inflate_state FAR *copy; + unsigned char FAR *window; + unsigned wsize; + + /* check input */ + if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL || + source->zalloc == (alloc_func)0 || source->zfree == (free_func)0) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)source->state; + + /* allocate space */ + copy = (struct inflate_state FAR *) + ZALLOC(source, 1, sizeof(struct inflate_state)); + if (copy == Z_NULL) return Z_MEM_ERROR; + window = Z_NULL; + if (state->window != Z_NULL) { + window = (unsigned char FAR *) + ZALLOC(source, 1U << state->wbits, sizeof(unsigned char)); + if (window == Z_NULL) { + ZFREE(source, copy); + return Z_MEM_ERROR; + } + } + + /* copy state */ + zmemcpy(dest, source, sizeof(z_stream)); + zmemcpy(copy, state, sizeof(struct inflate_state)); + if (state->lencode >= state->codes && + state->lencode <= state->codes + ENOUGH - 1) { + copy->lencode = copy->codes + (state->lencode - state->codes); + copy->distcode = copy->codes + (state->distcode - state->codes); + } + copy->next = copy->codes + (state->next - state->codes); + if (window != Z_NULL) { + wsize = 1U << state->wbits; + zmemcpy(window, state->window, wsize); + } + copy->window = window; + dest->state = (struct internal_state FAR *)copy; + return Z_OK; +} diff --git a/cbits/inftrees.c b/cbits/inftrees.c new file mode 100644 --- /dev/null +++ b/cbits/inftrees.c @@ -0,0 +1,329 @@ +/* inftrees.c -- generate Huffman trees for efficient decoding + * Copyright (C) 1995-2005 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "zutil.h" +#include "inftrees.h" + +#define MAXBITS 15 + +const char inflate_copyright[] = + " inflate 1.2.3 Copyright 1995-2005 Mark Adler "; +/* + If you use the zlib library in a product, an acknowledgment is welcome + in the documentation of your product. If for some reason you cannot + include such an acknowledgment, I would appreciate that you keep this + copyright string in the executable of your product. + */ + +/* + Build a set of tables to decode the provided canonical Huffman code. + The code lengths are lens[0..codes-1]. The result starts at *table, + whose indices are 0..2^bits-1. work is a writable array of at least + lens shorts, which is used as a work area. type is the type of code + to be generated, CODES, LENS, or DISTS. On return, zero is success, + -1 is an invalid code, and +1 means that ENOUGH isn't enough. table + on return points to the next available entry's address. bits is the + requested root table index bits, and on return it is the actual root + table index bits. It will differ if the request is greater than the + longest code or if it is less than the shortest code. + */ +int inflate_table(type, lens, codes, table, bits, work) +codetype type; +unsigned short FAR *lens; +unsigned codes; +code FAR * FAR *table; +unsigned FAR *bits; +unsigned short FAR *work; +{ + unsigned len; /* a code's length in bits */ + unsigned sym; /* index of code symbols */ + unsigned min, max; /* minimum and maximum code lengths */ + unsigned root; /* number of index bits for root table */ + unsigned curr; /* number of index bits for current table */ + unsigned drop; /* code bits to drop for sub-table */ + int left; /* number of prefix codes available */ + unsigned used; /* code entries in table used */ + unsigned huff; /* Huffman code */ + unsigned incr; /* for incrementing code, index */ + unsigned fill; /* index for replicating entries */ + unsigned low; /* low bits for current root entry */ + unsigned mask; /* mask for low root bits */ + code this; /* table entry for duplication */ + code FAR *next; /* next available space in table */ + const unsigned short FAR *base; /* base value table to use */ + const unsigned short FAR *extra; /* extra bits table to use */ + int end; /* use base and extra for symbol > end */ + unsigned short count[MAXBITS+1]; /* number of codes of each length */ + unsigned short offs[MAXBITS+1]; /* offsets in table for each length */ + static const unsigned short lbase[31] = { /* Length codes 257..285 base */ + 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, + 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; + static const unsigned short lext[31] = { /* Length codes 257..285 extra */ + 16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, + 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196}; + static const unsigned short dbase[32] = { /* Distance codes 0..29 base */ + 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, + 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, + 8193, 12289, 16385, 24577, 0, 0}; + static const unsigned short dext[32] = { /* Distance codes 0..29 extra */ + 16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, + 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, + 28, 28, 29, 29, 64, 64}; + + /* + Process a set of code lengths to create a canonical Huffman code. The + code lengths are lens[0..codes-1]. Each length corresponds to the + symbols 0..codes-1. The Huffman code is generated by first sorting the + symbols by length from short to long, and retaining the symbol order + for codes with equal lengths. Then the code starts with all zero bits + for the first code of the shortest length, and the codes are integer + increments for the same length, and zeros are appended as the length + increases. For the deflate format, these bits are stored backwards + from their more natural integer increment ordering, and so when the + decoding tables are built in the large loop below, the integer codes + are incremented backwards. + + This routine assumes, but does not check, that all of the entries in + lens[] are in the range 0..MAXBITS. The caller must assure this. + 1..MAXBITS is interpreted as that code length. zero means that that + symbol does not occur in this code. + + The codes are sorted by computing a count of codes for each length, + creating from that a table of starting indices for each length in the + sorted table, and then entering the symbols in order in the sorted + table. The sorted table is work[], with that space being provided by + the caller. + + The length counts are used for other purposes as well, i.e. finding + the minimum and maximum length codes, determining if there are any + codes at all, checking for a valid set of lengths, and looking ahead + at length counts to determine sub-table sizes when building the + decoding tables. + */ + + /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */ + for (len = 0; len <= MAXBITS; len++) + count[len] = 0; + for (sym = 0; sym < codes; sym++) + count[lens[sym]]++; + + /* bound code lengths, force root to be within code lengths */ + root = *bits; + for (max = MAXBITS; max >= 1; max--) + if (count[max] != 0) break; + if (root > max) root = max; + if (max == 0) { /* no symbols to code at all */ + this.op = (unsigned char)64; /* invalid code marker */ + this.bits = (unsigned char)1; + this.val = (unsigned short)0; + *(*table)++ = this; /* make a table to force an error */ + *(*table)++ = this; + *bits = 1; + return 0; /* no symbols, but wait for decoding to report error */ + } + for (min = 1; min <= MAXBITS; min++) + if (count[min] != 0) break; + if (root < min) root = min; + + /* check for an over-subscribed or incomplete set of lengths */ + left = 1; + for (len = 1; len <= MAXBITS; len++) { + left <<= 1; + left -= count[len]; + if (left < 0) return -1; /* over-subscribed */ + } + if (left > 0 && (type == CODES || max != 1)) + return -1; /* incomplete set */ + + /* generate offsets into symbol table for each length for sorting */ + offs[1] = 0; + for (len = 1; len < MAXBITS; len++) + offs[len + 1] = offs[len] + count[len]; + + /* sort symbols by length, by symbol order within each length */ + for (sym = 0; sym < codes; sym++) + if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym; + + /* + Create and fill in decoding tables. In this loop, the table being + filled is at next and has curr index bits. The code being used is huff + with length len. That code is converted to an index by dropping drop + bits off of the bottom. For codes where len is less than drop + curr, + those top drop + curr - len bits are incremented through all values to + fill the table with replicated entries. + + root is the number of index bits for the root table. When len exceeds + root, sub-tables are created pointed to by the root entry with an index + of the low root bits of huff. This is saved in low to check for when a + new sub-table should be started. drop is zero when the root table is + being filled, and drop is root when sub-tables are being filled. + + When a new sub-table is needed, it is necessary to look ahead in the + code lengths to determine what size sub-table is needed. The length + counts are used for this, and so count[] is decremented as codes are + entered in the tables. + + used keeps track of how many table entries have been allocated from the + provided *table space. It is checked when a LENS table is being made + against the space in *table, ENOUGH, minus the maximum space needed by + the worst case distance code, MAXD. This should never happen, but the + sufficiency of ENOUGH has not been proven exhaustively, hence the check. + This assumes that when type == LENS, bits == 9. + + sym increments through all symbols, and the loop terminates when + all codes of length max, i.e. all codes, have been processed. This + routine permits incomplete codes, so another loop after this one fills + in the rest of the decoding tables with invalid code markers. + */ + + /* set up for code type */ + switch (type) { + case CODES: + base = extra = work; /* dummy value--not used */ + end = 19; + break; + case LENS: + base = lbase; + base -= 257; + extra = lext; + extra -= 257; + end = 256; + break; + default: /* DISTS */ + base = dbase; + extra = dext; + end = -1; + } + + /* initialize state for loop */ + huff = 0; /* starting code */ + sym = 0; /* starting code symbol */ + len = min; /* starting code length */ + next = *table; /* current table to fill in */ + curr = root; /* current table index bits */ + drop = 0; /* current bits to drop from code for index */ + low = (unsigned)(-1); /* trigger new sub-table when len > root */ + used = 1U << root; /* use root table entries */ + mask = used - 1; /* mask for comparing low */ + + /* check available table space */ + if (type == LENS && used >= ENOUGH - MAXD) + return 1; + + /* process all codes and make table entries */ + for (;;) { + /* create table entry */ + this.bits = (unsigned char)(len - drop); + if ((int)(work[sym]) < end) { + this.op = (unsigned char)0; + this.val = work[sym]; + } + else if ((int)(work[sym]) > end) { + this.op = (unsigned char)(extra[work[sym]]); + this.val = base[work[sym]]; + } + else { + this.op = (unsigned char)(32 + 64); /* end of block */ + this.val = 0; + } + + /* replicate for those indices with low len bits equal to huff */ + incr = 1U << (len - drop); + fill = 1U << curr; + min = fill; /* save offset to next table */ + do { + fill -= incr; + next[(huff >> drop) + fill] = this; + } while (fill != 0); + + /* backwards increment the len-bit code huff */ + incr = 1U << (len - 1); + while (huff & incr) + incr >>= 1; + if (incr != 0) { + huff &= incr - 1; + huff += incr; + } + else + huff = 0; + + /* go to next symbol, update count, len */ + sym++; + if (--(count[len]) == 0) { + if (len == max) break; + len = lens[work[sym]]; + } + + /* create new sub-table if needed */ + if (len > root && (huff & mask) != low) { + /* if first time, transition to sub-tables */ + if (drop == 0) + drop = root; + + /* increment past last table */ + next += min; /* here min is 1 << curr */ + + /* determine length of next table */ + curr = len - drop; + left = (int)(1 << curr); + while (curr + drop < max) { + left -= count[curr + drop]; + if (left <= 0) break; + curr++; + left <<= 1; + } + + /* check for enough space */ + used += 1U << curr; + if (type == LENS && used >= ENOUGH - MAXD) + return 1; + + /* point entry in root table to sub-table */ + low = huff & mask; + (*table)[low].op = (unsigned char)curr; + (*table)[low].bits = (unsigned char)root; + (*table)[low].val = (unsigned short)(next - *table); + } + } + + /* + Fill in rest of table for incomplete codes. This loop is similar to the + loop above in incrementing huff for table indices. It is assumed that + len is equal to curr + drop, so there is no loop needed to increment + through high index bits. When the current sub-table is filled, the loop + drops back to the root table to fill in any remaining entries there. + */ + this.op = (unsigned char)64; /* invalid code marker */ + this.bits = (unsigned char)(len - drop); + this.val = (unsigned short)0; + while (huff != 0) { + /* when done with sub-table, drop back to root table */ + if (drop != 0 && (huff & mask) != low) { + drop = 0; + len = root; + next = *table; + this.bits = (unsigned char)len; + } + + /* put invalid code marker in table */ + next[huff >> drop] = this; + + /* backwards increment the len-bit code huff */ + incr = 1U << (len - 1); + while (huff & incr) + incr >>= 1; + if (incr != 0) { + huff &= incr - 1; + huff += incr; + } + else + huff = 0; + } + + /* set return parameters */ + *table += used; + *bits = root; + return 0; +} diff --git a/cbits/trees.c b/cbits/trees.c new file mode 100644 --- /dev/null +++ b/cbits/trees.c @@ -0,0 +1,1219 @@ +/* trees.c -- output deflated data using Huffman coding + * Copyright (C) 1995-2005 Jean-loup Gailly + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * ALGORITHM + * + * The "deflation" process uses several Huffman trees. The more + * common source values are represented by shorter bit sequences. + * + * Each code tree is stored in a compressed form which is itself + * a Huffman encoding of the lengths of all the code strings (in + * ascending order by source values). The actual code strings are + * reconstructed from the lengths in the inflate process, as described + * in the deflate specification. + * + * REFERENCES + * + * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". + * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc + * + * Storer, James A. + * Data Compression: Methods and Theory, pp. 49-50. + * Computer Science Press, 1988. ISBN 0-7167-8156-5. + * + * Sedgewick, R. + * Algorithms, p290. + * Addison-Wesley, 1983. ISBN 0-201-06672-6. + */ + +/* @(#) $Id$ */ + +/* #define GEN_TREES_H */ + +#include "deflate.h" + +#ifdef DEBUG +# include +#endif + +/* =========================================================================== + * Constants + */ + +#define MAX_BL_BITS 7 +/* Bit length codes must not exceed MAX_BL_BITS bits */ + +#define END_BLOCK 256 +/* end of block literal code */ + +#define REP_3_6 16 +/* repeat previous bit length 3-6 times (2 bits of repeat count) */ + +#define REPZ_3_10 17 +/* repeat a zero length 3-10 times (3 bits of repeat count) */ + +#define REPZ_11_138 18 +/* repeat a zero length 11-138 times (7 bits of repeat count) */ + +local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ + = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0}; + +local const int extra_dbits[D_CODES] /* extra bits for each distance code */ + = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}; + +local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */ + = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; + +local const uch bl_order[BL_CODES] + = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; +/* The lengths of the bit length codes are sent in order of decreasing + * probability, to avoid transmitting the lengths for unused bit length codes. + */ + +#define Buf_size (8 * 2*sizeof(char)) +/* Number of bits used within bi_buf. (bi_buf might be implemented on + * more than 16 bits on some systems.) + */ + +/* =========================================================================== + * Local data. These are initialized only once. + */ + +#define DIST_CODE_LEN 512 /* see definition of array dist_code below */ + +#if defined(GEN_TREES_H) || !defined(STDC) +/* non ANSI compilers may not accept trees.h */ + +local ct_data static_ltree[L_CODES+2]; +/* The static literal tree. Since the bit lengths are imposed, there is no + * need for the L_CODES extra codes used during heap construction. However + * The codes 286 and 287 are needed to build a canonical tree (see _tr_init + * below). + */ + +local ct_data static_dtree[D_CODES]; +/* The static distance tree. (Actually a trivial tree since all codes use + * 5 bits.) + */ + +uch _dist_code[DIST_CODE_LEN]; +/* Distance codes. The first 256 values correspond to the distances + * 3 .. 258, the last 256 values correspond to the top 8 bits of + * the 15 bit distances. + */ + +uch _length_code[MAX_MATCH-MIN_MATCH+1]; +/* length code for each normalized match length (0 == MIN_MATCH) */ + +local int base_length[LENGTH_CODES]; +/* First normalized length for each code (0 = MIN_MATCH) */ + +local int base_dist[D_CODES]; +/* First normalized distance for each code (0 = distance of 1) */ + +#else +# include "trees.h" +#endif /* GEN_TREES_H */ + +struct static_tree_desc_s { + const ct_data *static_tree; /* static tree or NULL */ + const intf *extra_bits; /* extra bits for each code or NULL */ + int extra_base; /* base index for extra_bits */ + int elems; /* max number of elements in the tree */ + int max_length; /* max bit length for the codes */ +}; + +local static_tree_desc static_l_desc = +{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; + +local static_tree_desc static_d_desc = +{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; + +local static_tree_desc static_bl_desc = +{(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; + +/* =========================================================================== + * Local (static) routines in this file. + */ + +local void tr_static_init OF((void)); +local void init_block OF((deflate_state *s)); +local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); +local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); +local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); +local void build_tree OF((deflate_state *s, tree_desc *desc)); +local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); +local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); +local int build_bl_tree OF((deflate_state *s)); +local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, + int blcodes)); +local void compress_block OF((deflate_state *s, ct_data *ltree, + ct_data *dtree)); +local void set_data_type OF((deflate_state *s)); +local unsigned bi_reverse OF((unsigned value, int length)); +local void bi_windup OF((deflate_state *s)); +local void bi_flush OF((deflate_state *s)); +local void copy_block OF((deflate_state *s, charf *buf, unsigned len, + int header)); + +#ifdef GEN_TREES_H +local void gen_trees_header OF((void)); +#endif + +#ifndef DEBUG +# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) + /* Send a code of the given tree. c and tree must not have side effects */ + +#else /* DEBUG */ +# define send_code(s, c, tree) \ + { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ + send_bits(s, tree[c].Code, tree[c].Len); } +#endif + +/* =========================================================================== + * Output a short LSB first on the stream. + * IN assertion: there is enough room in pendingBuf. + */ +#define put_short(s, w) { \ + put_byte(s, (uch)((w) & 0xff)); \ + put_byte(s, (uch)((ush)(w) >> 8)); \ +} + +/* =========================================================================== + * Send a value on a given number of bits. + * IN assertion: length <= 16 and value fits in length bits. + */ +#ifdef DEBUG +local void send_bits OF((deflate_state *s, int value, int length)); + +local void send_bits(s, value, length) + deflate_state *s; + int value; /* value to send */ + int length; /* number of bits */ +{ + Tracevv((stderr," l %2d v %4x ", length, value)); + Assert(length > 0 && length <= 15, "invalid length"); + s->bits_sent += (ulg)length; + + /* If not enough room in bi_buf, use (valid) bits from bi_buf and + * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) + * unused bits in value. + */ + if (s->bi_valid > (int)Buf_size - length) { + s->bi_buf |= (value << s->bi_valid); + put_short(s, s->bi_buf); + s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); + s->bi_valid += length - Buf_size; + } else { + s->bi_buf |= value << s->bi_valid; + s->bi_valid += length; + } +} +#else /* !DEBUG */ + +#define send_bits(s, value, length) \ +{ int len = length;\ + if (s->bi_valid > (int)Buf_size - len) {\ + int val = value;\ + s->bi_buf |= (val << s->bi_valid);\ + put_short(s, s->bi_buf);\ + s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ + s->bi_valid += len - Buf_size;\ + } else {\ + s->bi_buf |= (value) << s->bi_valid;\ + s->bi_valid += len;\ + }\ +} +#endif /* DEBUG */ + + +/* the arguments must not have side effects */ + +/* =========================================================================== + * Initialize the various 'constant' tables. + */ +local void tr_static_init() +{ +#if defined(GEN_TREES_H) || !defined(STDC) + static int static_init_done = 0; + int n; /* iterates over tree elements */ + int bits; /* bit counter */ + int length; /* length value */ + int code; /* code value */ + int dist; /* distance index */ + ush bl_count[MAX_BITS+1]; + /* number of codes at each bit length for an optimal tree */ + + if (static_init_done) return; + + /* For some embedded targets, global variables are not initialized: */ + static_l_desc.static_tree = static_ltree; + static_l_desc.extra_bits = extra_lbits; + static_d_desc.static_tree = static_dtree; + static_d_desc.extra_bits = extra_dbits; + static_bl_desc.extra_bits = extra_blbits; + + /* Initialize the mapping length (0..255) -> length code (0..28) */ + length = 0; + for (code = 0; code < LENGTH_CODES-1; code++) { + base_length[code] = length; + for (n = 0; n < (1< dist code (0..29) */ + dist = 0; + for (code = 0 ; code < 16; code++) { + base_dist[code] = dist; + for (n = 0; n < (1<>= 7; /* from now on, all distances are divided by 128 */ + for ( ; code < D_CODES; code++) { + base_dist[code] = dist << 7; + for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { + _dist_code[256 + dist++] = (uch)code; + } + } + Assert (dist == 256, "tr_static_init: 256+dist != 512"); + + /* Construct the codes of the static literal tree */ + for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; + n = 0; + while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; + while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; + while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; + while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; + /* Codes 286 and 287 do not exist, but we must include them in the + * tree construction to get a canonical Huffman tree (longest code + * all ones) + */ + gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); + + /* The static distance tree is trivial: */ + for (n = 0; n < D_CODES; n++) { + static_dtree[n].Len = 5; + static_dtree[n].Code = bi_reverse((unsigned)n, 5); + } + static_init_done = 1; + +# ifdef GEN_TREES_H + gen_trees_header(); +# endif +#endif /* defined(GEN_TREES_H) || !defined(STDC) */ +} + +/* =========================================================================== + * Genererate the file trees.h describing the static trees. + */ +#ifdef GEN_TREES_H +# ifndef DEBUG +# include +# endif + +# define SEPARATOR(i, last, width) \ + ((i) == (last)? "\n};\n\n" : \ + ((i) % (width) == (width)-1 ? ",\n" : ", ")) + +void gen_trees_header() +{ + FILE *header = fopen("trees.h", "w"); + int i; + + Assert (header != NULL, "Can't open trees.h"); + fprintf(header, + "/* header created automatically with -DGEN_TREES_H */\n\n"); + + fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); + for (i = 0; i < L_CODES+2; i++) { + fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, + static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); + } + + fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); + for (i = 0; i < D_CODES; i++) { + fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, + static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); + } + + fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n"); + for (i = 0; i < DIST_CODE_LEN; i++) { + fprintf(header, "%2u%s", _dist_code[i], + SEPARATOR(i, DIST_CODE_LEN-1, 20)); + } + + fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); + for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { + fprintf(header, "%2u%s", _length_code[i], + SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); + } + + fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); + for (i = 0; i < LENGTH_CODES; i++) { + fprintf(header, "%1u%s", base_length[i], + SEPARATOR(i, LENGTH_CODES-1, 20)); + } + + fprintf(header, "local const int base_dist[D_CODES] = {\n"); + for (i = 0; i < D_CODES; i++) { + fprintf(header, "%5u%s", base_dist[i], + SEPARATOR(i, D_CODES-1, 10)); + } + + fclose(header); +} +#endif /* GEN_TREES_H */ + +/* =========================================================================== + * Initialize the tree data structures for a new zlib stream. + */ +void _tr_init(s) + deflate_state *s; +{ + tr_static_init(); + + s->l_desc.dyn_tree = s->dyn_ltree; + s->l_desc.stat_desc = &static_l_desc; + + s->d_desc.dyn_tree = s->dyn_dtree; + s->d_desc.stat_desc = &static_d_desc; + + s->bl_desc.dyn_tree = s->bl_tree; + s->bl_desc.stat_desc = &static_bl_desc; + + s->bi_buf = 0; + s->bi_valid = 0; + s->last_eob_len = 8; /* enough lookahead for inflate */ +#ifdef DEBUG + s->compressed_len = 0L; + s->bits_sent = 0L; +#endif + + /* Initialize the first block of the first file: */ + init_block(s); +} + +/* =========================================================================== + * Initialize a new block. + */ +local void init_block(s) + deflate_state *s; +{ + int n; /* iterates over tree elements */ + + /* Initialize the trees. */ + for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; + for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; + for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; + + s->dyn_ltree[END_BLOCK].Freq = 1; + s->opt_len = s->static_len = 0L; + s->last_lit = s->matches = 0; +} + +#define SMALLEST 1 +/* Index within the heap array of least frequent node in the Huffman tree */ + + +/* =========================================================================== + * Remove the smallest element from the heap and recreate the heap with + * one less element. Updates heap and heap_len. + */ +#define pqremove(s, tree, top) \ +{\ + top = s->heap[SMALLEST]; \ + s->heap[SMALLEST] = s->heap[s->heap_len--]; \ + pqdownheap(s, tree, SMALLEST); \ +} + +/* =========================================================================== + * Compares to subtrees, using the tree depth as tie breaker when + * the subtrees have equal frequency. This minimizes the worst case length. + */ +#define smaller(tree, n, m, depth) \ + (tree[n].Freq < tree[m].Freq || \ + (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) + +/* =========================================================================== + * Restore the heap property by moving down the tree starting at node k, + * exchanging a node with the smallest of its two sons if necessary, stopping + * when the heap property is re-established (each father smaller than its + * two sons). + */ +local void pqdownheap(s, tree, k) + deflate_state *s; + ct_data *tree; /* the tree to restore */ + int k; /* node to move down */ +{ + int v = s->heap[k]; + int j = k << 1; /* left son of k */ + while (j <= s->heap_len) { + /* Set j to the smallest of the two sons: */ + if (j < s->heap_len && + smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { + j++; + } + /* Exit if v is smaller than both sons */ + if (smaller(tree, v, s->heap[j], s->depth)) break; + + /* Exchange v with the smallest son */ + s->heap[k] = s->heap[j]; k = j; + + /* And continue down the tree, setting j to the left son of k */ + j <<= 1; + } + s->heap[k] = v; +} + +/* =========================================================================== + * Compute the optimal bit lengths for a tree and update the total bit length + * for the current block. + * IN assertion: the fields freq and dad are set, heap[heap_max] and + * above are the tree nodes sorted by increasing frequency. + * OUT assertions: the field len is set to the optimal bit length, the + * array bl_count contains the frequencies for each bit length. + * The length opt_len is updated; static_len is also updated if stree is + * not null. + */ +local void gen_bitlen(s, desc) + deflate_state *s; + tree_desc *desc; /* the tree descriptor */ +{ + ct_data *tree = desc->dyn_tree; + int max_code = desc->max_code; + const ct_data *stree = desc->stat_desc->static_tree; + const intf *extra = desc->stat_desc->extra_bits; + int base = desc->stat_desc->extra_base; + int max_length = desc->stat_desc->max_length; + int h; /* heap index */ + int n, m; /* iterate over the tree elements */ + int bits; /* bit length */ + int xbits; /* extra bits */ + ush f; /* frequency */ + int overflow = 0; /* number of elements with bit length too large */ + + for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; + + /* In a first pass, compute the optimal bit lengths (which may + * overflow in the case of the bit length tree). + */ + tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ + + for (h = s->heap_max+1; h < HEAP_SIZE; h++) { + n = s->heap[h]; + bits = tree[tree[n].Dad].Len + 1; + if (bits > max_length) bits = max_length, overflow++; + tree[n].Len = (ush)bits; + /* We overwrite tree[n].Dad which is no longer needed */ + + if (n > max_code) continue; /* not a leaf node */ + + s->bl_count[bits]++; + xbits = 0; + if (n >= base) xbits = extra[n-base]; + f = tree[n].Freq; + s->opt_len += (ulg)f * (bits + xbits); + if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); + } + if (overflow == 0) return; + + Trace((stderr,"\nbit length overflow\n")); + /* This happens for example on obj2 and pic of the Calgary corpus */ + + /* Find the first bit length which could increase: */ + do { + bits = max_length-1; + while (s->bl_count[bits] == 0) bits--; + s->bl_count[bits]--; /* move one leaf down the tree */ + s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ + s->bl_count[max_length]--; + /* The brother of the overflow item also moves one step up, + * but this does not affect bl_count[max_length] + */ + overflow -= 2; + } while (overflow > 0); + + /* Now recompute all bit lengths, scanning in increasing frequency. + * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all + * lengths instead of fixing only the wrong ones. This idea is taken + * from 'ar' written by Haruhiko Okumura.) + */ + for (bits = max_length; bits != 0; bits--) { + n = s->bl_count[bits]; + while (n != 0) { + m = s->heap[--h]; + if (m > max_code) continue; + if ((unsigned) tree[m].Len != (unsigned) bits) { + Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); + s->opt_len += ((long)bits - (long)tree[m].Len) + *(long)tree[m].Freq; + tree[m].Len = (ush)bits; + } + n--; + } + } +} + +/* =========================================================================== + * Generate the codes for a given tree and bit counts (which need not be + * optimal). + * IN assertion: the array bl_count contains the bit length statistics for + * the given tree and the field len is set for all tree elements. + * OUT assertion: the field code is set for all tree elements of non + * zero code length. + */ +local void gen_codes (tree, max_code, bl_count) + ct_data *tree; /* the tree to decorate */ + int max_code; /* largest code with non zero frequency */ + ushf *bl_count; /* number of codes at each bit length */ +{ + ush next_code[MAX_BITS+1]; /* next code value for each bit length */ + ush code = 0; /* running code value */ + int bits; /* bit index */ + int n; /* code index */ + + /* The distribution counts are first used to generate the code values + * without bit reversal. + */ + for (bits = 1; bits <= MAX_BITS; bits++) { + next_code[bits] = code = (code + bl_count[bits-1]) << 1; + } + /* Check that the bit counts in bl_count are consistent. The last code + * must be all ones. + */ + Assert (code + bl_count[MAX_BITS]-1 == (1<dyn_tree; + const ct_data *stree = desc->stat_desc->static_tree; + int elems = desc->stat_desc->elems; + int n, m; /* iterate over heap elements */ + int max_code = -1; /* largest code with non zero frequency */ + int node; /* new node being created */ + + /* Construct the initial heap, with least frequent element in + * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. + * heap[0] is not used. + */ + s->heap_len = 0, s->heap_max = HEAP_SIZE; + + for (n = 0; n < elems; n++) { + if (tree[n].Freq != 0) { + s->heap[++(s->heap_len)] = max_code = n; + s->depth[n] = 0; + } else { + tree[n].Len = 0; + } + } + + /* The pkzip format requires that at least one distance code exists, + * and that at least one bit should be sent even if there is only one + * possible code. So to avoid special checks later on we force at least + * two codes of non zero frequency. + */ + while (s->heap_len < 2) { + node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); + tree[node].Freq = 1; + s->depth[node] = 0; + s->opt_len--; if (stree) s->static_len -= stree[node].Len; + /* node is 0 or 1 so it does not have extra bits */ + } + desc->max_code = max_code; + + /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, + * establish sub-heaps of increasing lengths: + */ + for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); + + /* Construct the Huffman tree by repeatedly combining the least two + * frequent nodes. + */ + node = elems; /* next internal node of the tree */ + do { + pqremove(s, tree, n); /* n = node of least frequency */ + m = s->heap[SMALLEST]; /* m = node of next least frequency */ + + s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ + s->heap[--(s->heap_max)] = m; + + /* Create a new node father of n and m */ + tree[node].Freq = tree[n].Freq + tree[m].Freq; + s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ? + s->depth[n] : s->depth[m]) + 1); + tree[n].Dad = tree[m].Dad = (ush)node; +#ifdef DUMP_BL_TREE + if (tree == s->bl_tree) { + fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", + node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); + } +#endif + /* and insert the new node in the heap */ + s->heap[SMALLEST] = node++; + pqdownheap(s, tree, SMALLEST); + + } while (s->heap_len >= 2); + + s->heap[--(s->heap_max)] = s->heap[SMALLEST]; + + /* At this point, the fields freq and dad are set. We can now + * generate the bit lengths. + */ + gen_bitlen(s, (tree_desc *)desc); + + /* The field len is now set, we can generate the bit codes */ + gen_codes ((ct_data *)tree, max_code, s->bl_count); +} + +/* =========================================================================== + * Scan a literal or distance tree to determine the frequencies of the codes + * in the bit length tree. + */ +local void scan_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + if (nextlen == 0) max_count = 138, min_count = 3; + tree[max_code+1].Len = (ush)0xffff; /* guard */ + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + s->bl_tree[curlen].Freq += count; + } else if (curlen != 0) { + if (curlen != prevlen) s->bl_tree[curlen].Freq++; + s->bl_tree[REP_3_6].Freq++; + } else if (count <= 10) { + s->bl_tree[REPZ_3_10].Freq++; + } else { + s->bl_tree[REPZ_11_138].Freq++; + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Send a literal or distance tree in compressed form, using the codes in + * bl_tree. + */ +local void send_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + /* tree[max_code+1].Len = -1; */ /* guard already set */ + if (nextlen == 0) max_count = 138, min_count = 3; + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + do { send_code(s, curlen, s->bl_tree); } while (--count != 0); + + } else if (curlen != 0) { + if (curlen != prevlen) { + send_code(s, curlen, s->bl_tree); count--; + } + Assert(count >= 3 && count <= 6, " 3_6?"); + send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); + + } else if (count <= 10) { + send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); + + } else { + send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Construct the Huffman tree for the bit lengths and return the index in + * bl_order of the last bit length code to send. + */ +local int build_bl_tree(s) + deflate_state *s; +{ + int max_blindex; /* index of last bit length code of non zero freq */ + + /* Determine the bit length frequencies for literal and distance trees */ + scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); + scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); + + /* Build the bit length tree: */ + build_tree(s, (tree_desc *)(&(s->bl_desc))); + /* opt_len now includes the length of the tree representations, except + * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. + */ + + /* Determine the number of bit length codes to send. The pkzip format + * requires that at least 4 bit length codes be sent. (appnote.txt says + * 3 but the actual value used is 4.) + */ + for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { + if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; + } + /* Update opt_len to include the bit length tree and counts */ + s->opt_len += 3*(max_blindex+1) + 5+5+4; + Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", + s->opt_len, s->static_len)); + + return max_blindex; +} + +/* =========================================================================== + * Send the header for a block using dynamic Huffman trees: the counts, the + * lengths of the bit length codes, the literal tree and the distance tree. + * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. + */ +local void send_all_trees(s, lcodes, dcodes, blcodes) + deflate_state *s; + int lcodes, dcodes, blcodes; /* number of codes for each tree */ +{ + int rank; /* index in bl_order */ + + Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); + Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, + "too many codes"); + Tracev((stderr, "\nbl counts: ")); + send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ + send_bits(s, dcodes-1, 5); + send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ + for (rank = 0; rank < blcodes; rank++) { + Tracev((stderr, "\nbl code %2d ", bl_order[rank])); + send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); + } + Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ + Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ + Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); +} + +/* =========================================================================== + * Send a stored block + */ +void _tr_stored_block(s, buf, stored_len, eof) + deflate_state *s; + charf *buf; /* input block */ + ulg stored_len; /* length of input block */ + int eof; /* true if this is the last block for a file */ +{ + send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ +#ifdef DEBUG + s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; + s->compressed_len += (stored_len + 4) << 3; +#endif + copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ +} + +/* =========================================================================== + * Send one empty static block to give enough lookahead for inflate. + * This takes 10 bits, of which 7 may remain in the bit buffer. + * The current inflate code requires 9 bits of lookahead. If the + * last two codes for the previous block (real code plus EOB) were coded + * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode + * the last real code. In this case we send two empty static blocks instead + * of one. (There are no problems if the previous block is stored or fixed.) + * To simplify the code, we assume the worst case of last real code encoded + * on one bit only. + */ +void _tr_align(s) + deflate_state *s; +{ + send_bits(s, STATIC_TREES<<1, 3); + send_code(s, END_BLOCK, static_ltree); +#ifdef DEBUG + s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ +#endif + bi_flush(s); + /* Of the 10 bits for the empty block, we have already sent + * (10 - bi_valid) bits. The lookahead for the last real code (before + * the EOB of the previous block) was thus at least one plus the length + * of the EOB plus what we have just sent of the empty static block. + */ + if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { + send_bits(s, STATIC_TREES<<1, 3); + send_code(s, END_BLOCK, static_ltree); +#ifdef DEBUG + s->compressed_len += 10L; +#endif + bi_flush(s); + } + s->last_eob_len = 7; +} + +/* =========================================================================== + * Determine the best encoding for the current block: dynamic trees, static + * trees or store, and output the encoded block to the zip file. + */ +void _tr_flush_block(s, buf, stored_len, eof) + deflate_state *s; + charf *buf; /* input block, or NULL if too old */ + ulg stored_len; /* length of input block */ + int eof; /* true if this is the last block for a file */ +{ + ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ + int max_blindex = 0; /* index of last bit length code of non zero freq */ + + /* Build the Huffman trees unless a stored block is forced */ + if (s->level > 0) { + + /* Check if the file is binary or text */ + if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN) + set_data_type(s); + + /* Construct the literal and distance trees */ + build_tree(s, (tree_desc *)(&(s->l_desc))); + Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + + build_tree(s, (tree_desc *)(&(s->d_desc))); + Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + /* At this point, opt_len and static_len are the total bit lengths of + * the compressed block data, excluding the tree representations. + */ + + /* Build the bit length tree for the above two trees, and get the index + * in bl_order of the last bit length code to send. + */ + max_blindex = build_bl_tree(s); + + /* Determine the best encoding. Compute the block lengths in bytes. */ + opt_lenb = (s->opt_len+3+7)>>3; + static_lenb = (s->static_len+3+7)>>3; + + Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", + opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, + s->last_lit)); + + if (static_lenb <= opt_lenb) opt_lenb = static_lenb; + + } else { + Assert(buf != (char*)0, "lost buf"); + opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ + } + +#ifdef FORCE_STORED + if (buf != (char*)0) { /* force stored block */ +#else + if (stored_len+4 <= opt_lenb && buf != (char*)0) { + /* 4: two words for the lengths */ +#endif + /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. + * Otherwise we can't have processed more than WSIZE input bytes since + * the last block flush, because compression would have been + * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to + * transform a block into a stored block. + */ + _tr_stored_block(s, buf, stored_len, eof); + +#ifdef FORCE_STATIC + } else if (static_lenb >= 0) { /* force static trees */ +#else + } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) { +#endif + send_bits(s, (STATIC_TREES<<1)+eof, 3); + compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); +#ifdef DEBUG + s->compressed_len += 3 + s->static_len; +#endif + } else { + send_bits(s, (DYN_TREES<<1)+eof, 3); + send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, + max_blindex+1); + compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); +#ifdef DEBUG + s->compressed_len += 3 + s->opt_len; +#endif + } + Assert (s->compressed_len == s->bits_sent, "bad compressed size"); + /* The above check is made mod 2^32, for files larger than 512 MB + * and uLong implemented on 32 bits. + */ + init_block(s); + + if (eof) { + bi_windup(s); +#ifdef DEBUG + s->compressed_len += 7; /* align on byte boundary */ +#endif + } + Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, + s->compressed_len-7*eof)); +} + +/* =========================================================================== + * Save the match info and tally the frequency counts. Return true if + * the current block must be flushed. + */ +int _tr_tally (s, dist, lc) + deflate_state *s; + unsigned dist; /* distance of matched string */ + unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ +{ + s->d_buf[s->last_lit] = (ush)dist; + s->l_buf[s->last_lit++] = (uch)lc; + if (dist == 0) { + /* lc is the unmatched char */ + s->dyn_ltree[lc].Freq++; + } else { + s->matches++; + /* Here, lc is the match length - MIN_MATCH */ + dist--; /* dist = match distance - 1 */ + Assert((ush)dist < (ush)MAX_DIST(s) && + (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && + (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); + + s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; + s->dyn_dtree[d_code(dist)].Freq++; + } + +#ifdef TRUNCATE_BLOCK + /* Try to guess if it is profitable to stop the current block here */ + if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { + /* Compute an upper bound for the compressed length */ + ulg out_length = (ulg)s->last_lit*8L; + ulg in_length = (ulg)((long)s->strstart - s->block_start); + int dcode; + for (dcode = 0; dcode < D_CODES; dcode++) { + out_length += (ulg)s->dyn_dtree[dcode].Freq * + (5L+extra_dbits[dcode]); + } + out_length >>= 3; + Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", + s->last_lit, in_length, out_length, + 100L - out_length*100L/in_length)); + if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; + } +#endif + return (s->last_lit == s->lit_bufsize-1); + /* We avoid equality with lit_bufsize because of wraparound at 64K + * on 16 bit machines and because stored blocks are restricted to + * 64K-1 bytes. + */ +} + +/* =========================================================================== + * Send the block data compressed using the given Huffman trees + */ +local void compress_block(s, ltree, dtree) + deflate_state *s; + ct_data *ltree; /* literal tree */ + ct_data *dtree; /* distance tree */ +{ + unsigned dist; /* distance of matched string */ + int lc; /* match length or unmatched char (if dist == 0) */ + unsigned lx = 0; /* running index in l_buf */ + unsigned code; /* the code to send */ + int extra; /* number of extra bits to send */ + + if (s->last_lit != 0) do { + dist = s->d_buf[lx]; + lc = s->l_buf[lx++]; + if (dist == 0) { + send_code(s, lc, ltree); /* send a literal byte */ + Tracecv(isgraph(lc), (stderr," '%c' ", lc)); + } else { + /* Here, lc is the match length - MIN_MATCH */ + code = _length_code[lc]; + send_code(s, code+LITERALS+1, ltree); /* send the length code */ + extra = extra_lbits[code]; + if (extra != 0) { + lc -= base_length[code]; + send_bits(s, lc, extra); /* send the extra length bits */ + } + dist--; /* dist is now the match distance - 1 */ + code = d_code(dist); + Assert (code < D_CODES, "bad d_code"); + + send_code(s, code, dtree); /* send the distance code */ + extra = extra_dbits[code]; + if (extra != 0) { + dist -= base_dist[code]; + send_bits(s, dist, extra); /* send the extra distance bits */ + } + } /* literal or match pair ? */ + + /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ + Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, + "pendingBuf overflow"); + + } while (lx < s->last_lit); + + send_code(s, END_BLOCK, ltree); + s->last_eob_len = ltree[END_BLOCK].Len; +} + +/* =========================================================================== + * Set the data type to BINARY or TEXT, using a crude approximation: + * set it to Z_TEXT if all symbols are either printable characters (33 to 255) + * or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise. + * IN assertion: the fields Freq of dyn_ltree are set. + */ +local void set_data_type(s) + deflate_state *s; +{ + int n; + + for (n = 0; n < 9; n++) + if (s->dyn_ltree[n].Freq != 0) + break; + if (n == 9) + for (n = 14; n < 32; n++) + if (s->dyn_ltree[n].Freq != 0) + break; + s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY; +} + +/* =========================================================================== + * Reverse the first len bits of a code, using straightforward code (a faster + * method would use a table) + * IN assertion: 1 <= len <= 15 + */ +local unsigned bi_reverse(code, len) + unsigned code; /* the value to invert */ + int len; /* its bit length */ +{ + register unsigned res = 0; + do { + res |= code & 1; + code >>= 1, res <<= 1; + } while (--len > 0); + return res >> 1; +} + +/* =========================================================================== + * Flush the bit buffer, keeping at most 7 bits in it. + */ +local void bi_flush(s) + deflate_state *s; +{ + if (s->bi_valid == 16) { + put_short(s, s->bi_buf); + s->bi_buf = 0; + s->bi_valid = 0; + } else if (s->bi_valid >= 8) { + put_byte(s, (Byte)s->bi_buf); + s->bi_buf >>= 8; + s->bi_valid -= 8; + } +} + +/* =========================================================================== + * Flush the bit buffer and align the output on a byte boundary + */ +local void bi_windup(s) + deflate_state *s; +{ + if (s->bi_valid > 8) { + put_short(s, s->bi_buf); + } else if (s->bi_valid > 0) { + put_byte(s, (Byte)s->bi_buf); + } + s->bi_buf = 0; + s->bi_valid = 0; +#ifdef DEBUG + s->bits_sent = (s->bits_sent+7) & ~7; +#endif +} + +/* =========================================================================== + * Copy a stored block, storing first the length and its + * one's complement if requested. + */ +local void copy_block(s, buf, len, header) + deflate_state *s; + charf *buf; /* the input data */ + unsigned len; /* its length */ + int header; /* true if block header must be written */ +{ + bi_windup(s); /* align on byte boundary */ + s->last_eob_len = 8; /* enough lookahead for inflate */ + + if (header) { + put_short(s, (ush)len); + put_short(s, (ush)~len); +#ifdef DEBUG + s->bits_sent += 2*16; +#endif + } +#ifdef DEBUG + s->bits_sent += (ulg)len<<3; +#endif + while (len--) { + put_byte(s, *buf++); + } +} diff --git a/cbits/uncompr.c b/cbits/uncompr.c new file mode 100644 --- /dev/null +++ b/cbits/uncompr.c @@ -0,0 +1,61 @@ +/* uncompr.c -- decompress a memory buffer + * Copyright (C) 1995-2003 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id$ */ + +#define ZLIB_INTERNAL +#include "zlib.h" + +/* =========================================================================== + Decompresses the source buffer into the destination buffer. sourceLen is + the byte length of the source buffer. Upon entry, destLen is the total + size of the destination buffer, which must be large enough to hold the + entire uncompressed data. (The size of the uncompressed data must have + been saved previously by the compressor and transmitted to the decompressor + by some mechanism outside the scope of this compression library.) + Upon exit, destLen is the actual size of the compressed buffer. + This function can be used to decompress a whole file at once if the + input file is mmap'ed. + + uncompress returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_BUF_ERROR if there was not enough room in the output + buffer, or Z_DATA_ERROR if the input data was corrupted. +*/ +int ZEXPORT uncompress (dest, destLen, source, sourceLen) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; +{ + z_stream stream; + int err; + + stream.next_in = (Bytef*)source; + stream.avail_in = (uInt)sourceLen; + /* Check for source > 64K on 16-bit machine: */ + if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR; + + stream.next_out = dest; + stream.avail_out = (uInt)*destLen; + if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR; + + stream.zalloc = (alloc_func)0; + stream.zfree = (free_func)0; + + err = inflateInit(&stream); + if (err != Z_OK) return err; + + err = inflate(&stream, Z_FINISH); + if (err != Z_STREAM_END) { + inflateEnd(&stream); + if (err == Z_NEED_DICT || (err == Z_BUF_ERROR && stream.avail_in == 0)) + return Z_DATA_ERROR; + return err; + } + *destLen = stream.total_out; + + err = inflateEnd(&stream); + return err; +} diff --git a/cbits/zlib.h b/cbits/zlib.h new file mode 100644 --- /dev/null +++ b/cbits/zlib.h @@ -0,0 +1,1357 @@ +/* zlib.h -- interface of the 'zlib' general purpose compression library + version 1.2.3, July 18th, 2005 + + Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. + + Jean-loup Gailly Mark Adler + jloup@gzip.org madler@alumni.caltech.edu + + + The data format used by the zlib library is described by RFCs (Request for + Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt + (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). +*/ + +#ifndef ZLIB_H +#define ZLIB_H + +#include "zconf.h" + +#ifdef __cplusplus +extern "C" { +#endif + +#define ZLIB_VERSION "1.2.3" +#define ZLIB_VERNUM 0x1230 + +/* + The 'zlib' compression library provides in-memory compression and + decompression functions, including integrity checks of the uncompressed + data. This version of the library supports only one compression method + (deflation) but other algorithms will be added later and will have the same + stream interface. + + Compression can be done in a single step if the buffers are large + enough (for example if an input file is mmap'ed), or can be done by + repeated calls of the compression function. In the latter case, the + application must provide more input and/or consume the output + (providing more output space) before each call. + + The compressed data format used by default by the in-memory functions is + the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped + around a deflate stream, which is itself documented in RFC 1951. + + The library also supports reading and writing files in gzip (.gz) format + with an interface similar to that of stdio using the functions that start + with "gz". The gzip format is different from the zlib format. gzip is a + gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. + + This library can optionally read and write gzip streams in memory as well. + + The zlib format was designed to be compact and fast for use in memory + and on communications channels. The gzip format was designed for single- + file compression on file systems, has a larger header than zlib to maintain + directory information, and uses a different, slower check method than zlib. + + The library does not install any signal handler. The decoder checks + the consistency of the compressed data, so the library should never + crash even in case of corrupted input. +*/ + +typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); +typedef void (*free_func) OF((voidpf opaque, voidpf address)); + +struct internal_state; + +typedef struct z_stream_s { + Bytef *next_in; /* next input byte */ + uInt avail_in; /* number of bytes available at next_in */ + uLong total_in; /* total nb of input bytes read so far */ + + Bytef *next_out; /* next output byte should be put there */ + uInt avail_out; /* remaining free space at next_out */ + uLong total_out; /* total nb of bytes output so far */ + + char *msg; /* last error message, NULL if no error */ + struct internal_state FAR *state; /* not visible by applications */ + + alloc_func zalloc; /* used to allocate the internal state */ + free_func zfree; /* used to free the internal state */ + voidpf opaque; /* private data object passed to zalloc and zfree */ + + int data_type; /* best guess about the data type: binary or text */ + uLong adler; /* adler32 value of the uncompressed data */ + uLong reserved; /* reserved for future use */ +} z_stream; + +typedef z_stream FAR *z_streamp; + +/* + gzip header information passed to and from zlib routines. See RFC 1952 + for more details on the meanings of these fields. +*/ +typedef struct gz_header_s { + int text; /* true if compressed data believed to be text */ + uLong time; /* modification time */ + int xflags; /* extra flags (not used when writing a gzip file) */ + int os; /* operating system */ + Bytef *extra; /* pointer to extra field or Z_NULL if none */ + uInt extra_len; /* extra field length (valid if extra != Z_NULL) */ + uInt extra_max; /* space at extra (only when reading header) */ + Bytef *name; /* pointer to zero-terminated file name or Z_NULL */ + uInt name_max; /* space at name (only when reading header) */ + Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */ + uInt comm_max; /* space at comment (only when reading header) */ + int hcrc; /* true if there was or will be a header crc */ + int done; /* true when done reading gzip header (not used + when writing a gzip file) */ +} gz_header; + +typedef gz_header FAR *gz_headerp; + +/* + The application must update next_in and avail_in when avail_in has + dropped to zero. It must update next_out and avail_out when avail_out + has dropped to zero. The application must initialize zalloc, zfree and + opaque before calling the init function. All other fields are set by the + compression library and must not be updated by the application. + + The opaque value provided by the application will be passed as the first + parameter for calls of zalloc and zfree. This can be useful for custom + memory management. The compression library attaches no meaning to the + opaque value. + + zalloc must return Z_NULL if there is not enough memory for the object. + If zlib is used in a multi-threaded application, zalloc and zfree must be + thread safe. + + On 16-bit systems, the functions zalloc and zfree must be able to allocate + exactly 65536 bytes, but will not be required to allocate more than this + if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, + pointers returned by zalloc for objects of exactly 65536 bytes *must* + have their offset normalized to zero. The default allocation function + provided by this library ensures this (see zutil.c). To reduce memory + requirements and avoid any allocation of 64K objects, at the expense of + compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). + + The fields total_in and total_out can be used for statistics or + progress reports. After compression, total_in holds the total size of + the uncompressed data and may be saved for use in the decompressor + (particularly if the decompressor wants to decompress everything in + a single step). +*/ + + /* constants */ + +#define Z_NO_FLUSH 0 +#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ +#define Z_SYNC_FLUSH 2 +#define Z_FULL_FLUSH 3 +#define Z_FINISH 4 +#define Z_BLOCK 5 +/* Allowed flush values; see deflate() and inflate() below for details */ + +#define Z_OK 0 +#define Z_STREAM_END 1 +#define Z_NEED_DICT 2 +#define Z_ERRNO (-1) +#define Z_STREAM_ERROR (-2) +#define Z_DATA_ERROR (-3) +#define Z_MEM_ERROR (-4) +#define Z_BUF_ERROR (-5) +#define Z_VERSION_ERROR (-6) +/* Return codes for the compression/decompression functions. Negative + * values are errors, positive values are used for special but normal events. + */ + +#define Z_NO_COMPRESSION 0 +#define Z_BEST_SPEED 1 +#define Z_BEST_COMPRESSION 9 +#define Z_DEFAULT_COMPRESSION (-1) +/* compression levels */ + +#define Z_FILTERED 1 +#define Z_HUFFMAN_ONLY 2 +#define Z_RLE 3 +#define Z_FIXED 4 +#define Z_DEFAULT_STRATEGY 0 +/* compression strategy; see deflateInit2() below for details */ + +#define Z_BINARY 0 +#define Z_TEXT 1 +#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ +#define Z_UNKNOWN 2 +/* Possible values of the data_type field (though see inflate()) */ + +#define Z_DEFLATED 8 +/* The deflate compression method (the only one supported in this version) */ + +#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ + +#define zlib_version zlibVersion() +/* for compatibility with versions < 1.0.2 */ + + /* basic functions */ + +ZEXTERN const char * ZEXPORT zlibVersion OF((void)); +/* The application can compare zlibVersion and ZLIB_VERSION for consistency. + If the first character differs, the library code actually used is + not compatible with the zlib.h header file used by the application. + This check is automatically made by deflateInit and inflateInit. + */ + +/* +ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); + + Initializes the internal stream state for compression. The fields + zalloc, zfree and opaque must be initialized before by the caller. + If zalloc and zfree are set to Z_NULL, deflateInit updates them to + use default allocation functions. + + The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: + 1 gives best speed, 9 gives best compression, 0 gives no compression at + all (the input data is simply copied a block at a time). + Z_DEFAULT_COMPRESSION requests a default compromise between speed and + compression (currently equivalent to level 6). + + deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_STREAM_ERROR if level is not a valid compression level, + Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible + with the version assumed by the caller (ZLIB_VERSION). + msg is set to null if there is no error message. deflateInit does not + perform any compression: this will be done by deflate(). +*/ + + +ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); +/* + deflate compresses as much data as possible, and stops when the input + buffer becomes empty or the output buffer becomes full. It may introduce some + output latency (reading input without producing any output) except when + forced to flush. + + The detailed semantics are as follows. deflate performs one or both of the + following actions: + + - Compress more input starting at next_in and update next_in and avail_in + accordingly. If not all input can be processed (because there is not + enough room in the output buffer), next_in and avail_in are updated and + processing will resume at this point for the next call of deflate(). + + - Provide more output starting at next_out and update next_out and avail_out + accordingly. This action is forced if the parameter flush is non zero. + Forcing flush frequently degrades the compression ratio, so this parameter + should be set only when necessary (in interactive applications). + Some output may be provided even if flush is not set. + + Before the call of deflate(), the application should ensure that at least + one of the actions is possible, by providing more input and/or consuming + more output, and updating avail_in or avail_out accordingly; avail_out + should never be zero before the call. The application can consume the + compressed output when it wants, for example when the output buffer is full + (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK + and with zero avail_out, it must be called again after making room in the + output buffer because there might be more output pending. + + Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to + decide how much data to accumualte before producing output, in order to + maximize compression. + + If the parameter flush is set to Z_SYNC_FLUSH, all pending output is + flushed to the output buffer and the output is aligned on a byte boundary, so + that the decompressor can get all input data available so far. (In particular + avail_in is zero after the call if enough output space has been provided + before the call.) Flushing may degrade compression for some compression + algorithms and so it should be used only when necessary. + + If flush is set to Z_FULL_FLUSH, all output is flushed as with + Z_SYNC_FLUSH, and the compression state is reset so that decompression can + restart from this point if previous compressed data has been damaged or if + random access is desired. Using Z_FULL_FLUSH too often can seriously degrade + compression. + + If deflate returns with avail_out == 0, this function must be called again + with the same value of the flush parameter and more output space (updated + avail_out), until the flush is complete (deflate returns with non-zero + avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that + avail_out is greater than six to avoid repeated flush markers due to + avail_out == 0 on return. + + If the parameter flush is set to Z_FINISH, pending input is processed, + pending output is flushed and deflate returns with Z_STREAM_END if there + was enough output space; if deflate returns with Z_OK, this function must be + called again with Z_FINISH and more output space (updated avail_out) but no + more input data, until it returns with Z_STREAM_END or an error. After + deflate has returned Z_STREAM_END, the only possible operations on the + stream are deflateReset or deflateEnd. + + Z_FINISH can be used immediately after deflateInit if all the compression + is to be done in a single step. In this case, avail_out must be at least + the value returned by deflateBound (see below). If deflate does not return + Z_STREAM_END, then it must be called again as described above. + + deflate() sets strm->adler to the adler32 checksum of all input read + so far (that is, total_in bytes). + + deflate() may update strm->data_type if it can make a good guess about + the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered + binary. This field is only for information purposes and does not affect + the compression algorithm in any manner. + + deflate() returns Z_OK if some progress has been made (more input + processed or more output produced), Z_STREAM_END if all input has been + consumed and all output has been produced (only when flush is set to + Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example + if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible + (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not + fatal, and deflate() can be called again with more input and more output + space to continue compressing. +*/ + + +ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); +/* + All dynamically allocated data structures for this stream are freed. + This function discards any unprocessed input and does not flush any + pending output. + + deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the + stream state was inconsistent, Z_DATA_ERROR if the stream was freed + prematurely (some input or output was discarded). In the error case, + msg may be set but then points to a static string (which must not be + deallocated). +*/ + + +/* +ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); + + Initializes the internal stream state for decompression. The fields + next_in, avail_in, zalloc, zfree and opaque must be initialized before by + the caller. If next_in is not Z_NULL and avail_in is large enough (the exact + value depends on the compression method), inflateInit determines the + compression method from the zlib header and allocates all data structures + accordingly; otherwise the allocation will be deferred to the first call of + inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to + use default allocation functions. + + inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_VERSION_ERROR if the zlib library version is incompatible with the + version assumed by the caller. msg is set to null if there is no error + message. inflateInit does not perform any decompression apart from reading + the zlib header if present: this will be done by inflate(). (So next_in and + avail_in may be modified, but next_out and avail_out are unchanged.) +*/ + + +ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); +/* + inflate decompresses as much data as possible, and stops when the input + buffer becomes empty or the output buffer becomes full. It may introduce + some output latency (reading input without producing any output) except when + forced to flush. + + The detailed semantics are as follows. inflate performs one or both of the + following actions: + + - Decompress more input starting at next_in and update next_in and avail_in + accordingly. If not all input can be processed (because there is not + enough room in the output buffer), next_in is updated and processing + will resume at this point for the next call of inflate(). + + - Provide more output starting at next_out and update next_out and avail_out + accordingly. inflate() provides as much output as possible, until there + is no more input data or no more space in the output buffer (see below + about the flush parameter). + + Before the call of inflate(), the application should ensure that at least + one of the actions is possible, by providing more input and/or consuming + more output, and updating the next_* and avail_* values accordingly. + The application can consume the uncompressed output when it wants, for + example when the output buffer is full (avail_out == 0), or after each + call of inflate(). If inflate returns Z_OK and with zero avail_out, it + must be called again after making room in the output buffer because there + might be more output pending. + + The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, + Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much + output as possible to the output buffer. Z_BLOCK requests that inflate() stop + if and when it gets to the next deflate block boundary. When decoding the + zlib or gzip format, this will cause inflate() to return immediately after + the header and before the first block. When doing a raw inflate, inflate() + will go ahead and process the first block, and will return when it gets to + the end of that block, or when it runs out of data. + + The Z_BLOCK option assists in appending to or combining deflate streams. + Also to assist in this, on return inflate() will set strm->data_type to the + number of unused bits in the last byte taken from strm->next_in, plus 64 + if inflate() is currently decoding the last block in the deflate stream, + plus 128 if inflate() returned immediately after decoding an end-of-block + code or decoding the complete header up to just before the first byte of the + deflate stream. The end-of-block will not be indicated until all of the + uncompressed data from that block has been written to strm->next_out. The + number of unused bits may in general be greater than seven, except when + bit 7 of data_type is set, in which case the number of unused bits will be + less than eight. + + inflate() should normally be called until it returns Z_STREAM_END or an + error. However if all decompression is to be performed in a single step + (a single call of inflate), the parameter flush should be set to + Z_FINISH. In this case all pending input is processed and all pending + output is flushed; avail_out must be large enough to hold all the + uncompressed data. (The size of the uncompressed data may have been saved + by the compressor for this purpose.) The next operation on this stream must + be inflateEnd to deallocate the decompression state. The use of Z_FINISH + is never required, but can be used to inform inflate that a faster approach + may be used for the single inflate() call. + + In this implementation, inflate() always flushes as much output as + possible to the output buffer, and always uses the faster approach on the + first call. So the only effect of the flush parameter in this implementation + is on the return value of inflate(), as noted below, or when it returns early + because Z_BLOCK is used. + + If a preset dictionary is needed after this call (see inflateSetDictionary + below), inflate sets strm->adler to the adler32 checksum of the dictionary + chosen by the compressor and returns Z_NEED_DICT; otherwise it sets + strm->adler to the adler32 checksum of all output produced so far (that is, + total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described + below. At the end of the stream, inflate() checks that its computed adler32 + checksum is equal to that saved by the compressor and returns Z_STREAM_END + only if the checksum is correct. + + inflate() will decompress and check either zlib-wrapped or gzip-wrapped + deflate data. The header type is detected automatically. Any information + contained in the gzip header is not retained, so applications that need that + information should instead use raw inflate, see inflateInit2() below, or + inflateBack() and perform their own processing of the gzip header and + trailer. + + inflate() returns Z_OK if some progress has been made (more input processed + or more output produced), Z_STREAM_END if the end of the compressed data has + been reached and all uncompressed output has been produced, Z_NEED_DICT if a + preset dictionary is needed at this point, Z_DATA_ERROR if the input data was + corrupted (input stream not conforming to the zlib format or incorrect check + value), Z_STREAM_ERROR if the stream structure was inconsistent (for example + if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, + Z_BUF_ERROR if no progress is possible or if there was not enough room in the + output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and + inflate() can be called again with more input and more output space to + continue decompressing. If Z_DATA_ERROR is returned, the application may then + call inflateSync() to look for a good compression block if a partial recovery + of the data is desired. +*/ + + +ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); +/* + All dynamically allocated data structures for this stream are freed. + This function discards any unprocessed input and does not flush any + pending output. + + inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state + was inconsistent. In the error case, msg may be set but then points to a + static string (which must not be deallocated). +*/ + + /* Advanced functions */ + +/* + The following functions are needed only in some special applications. +*/ + +/* +ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, + int level, + int method, + int windowBits, + int memLevel, + int strategy)); + + This is another version of deflateInit with more compression options. The + fields next_in, zalloc, zfree and opaque must be initialized before by + the caller. + + The method parameter is the compression method. It must be Z_DEFLATED in + this version of the library. + + The windowBits parameter is the base two logarithm of the window size + (the size of the history buffer). It should be in the range 8..15 for this + version of the library. Larger values of this parameter result in better + compression at the expense of memory usage. The default value is 15 if + deflateInit is used instead. + + windowBits can also be -8..-15 for raw deflate. In this case, -windowBits + determines the window size. deflate() will then generate raw deflate data + with no zlib header or trailer, and will not compute an adler32 check value. + + windowBits can also be greater than 15 for optional gzip encoding. Add + 16 to windowBits to write a simple gzip header and trailer around the + compressed data instead of a zlib wrapper. The gzip header will have no + file name, no extra data, no comment, no modification time (set to zero), + no header crc, and the operating system will be set to 255 (unknown). If a + gzip stream is being written, strm->adler is a crc32 instead of an adler32. + + The memLevel parameter specifies how much memory should be allocated + for the internal compression state. memLevel=1 uses minimum memory but + is slow and reduces compression ratio; memLevel=9 uses maximum memory + for optimal speed. The default value is 8. See zconf.h for total memory + usage as a function of windowBits and memLevel. + + The strategy parameter is used to tune the compression algorithm. Use the + value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a + filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no + string match), or Z_RLE to limit match distances to one (run-length + encoding). Filtered data consists mostly of small values with a somewhat + random distribution. In this case, the compression algorithm is tuned to + compress them better. The effect of Z_FILTERED is to force more Huffman + coding and less string matching; it is somewhat intermediate between + Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as + Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy + parameter only affects the compression ratio but not the correctness of the + compressed output even if it is not set appropriately. Z_FIXED prevents the + use of dynamic Huffman codes, allowing for a simpler decoder for special + applications. + + deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid + method). msg is set to null if there is no error message. deflateInit2 does + not perform any compression: this will be done by deflate(). +*/ + +ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, + const Bytef *dictionary, + uInt dictLength)); +/* + Initializes the compression dictionary from the given byte sequence + without producing any compressed output. This function must be called + immediately after deflateInit, deflateInit2 or deflateReset, before any + call of deflate. The compressor and decompressor must use exactly the same + dictionary (see inflateSetDictionary). + + The dictionary should consist of strings (byte sequences) that are likely + to be encountered later in the data to be compressed, with the most commonly + used strings preferably put towards the end of the dictionary. Using a + dictionary is most useful when the data to be compressed is short and can be + predicted with good accuracy; the data can then be compressed better than + with the default empty dictionary. + + Depending on the size of the compression data structures selected by + deflateInit or deflateInit2, a part of the dictionary may in effect be + discarded, for example if the dictionary is larger than the window size in + deflate or deflate2. Thus the strings most likely to be useful should be + put at the end of the dictionary, not at the front. In addition, the + current implementation of deflate will use at most the window size minus + 262 bytes of the provided dictionary. + + Upon return of this function, strm->adler is set to the adler32 value + of the dictionary; the decompressor may later use this value to determine + which dictionary has been used by the compressor. (The adler32 value + applies to the whole dictionary even if only a subset of the dictionary is + actually used by the compressor.) If a raw deflate was requested, then the + adler32 value is not computed and strm->adler is not set. + + deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a + parameter is invalid (such as NULL dictionary) or the stream state is + inconsistent (for example if deflate has already been called for this stream + or if the compression method is bsort). deflateSetDictionary does not + perform any compression: this will be done by deflate(). +*/ + +ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, + z_streamp source)); +/* + Sets the destination stream as a complete copy of the source stream. + + This function can be useful when several compression strategies will be + tried, for example when there are several ways of pre-processing the input + data with a filter. The streams that will be discarded should then be freed + by calling deflateEnd. Note that deflateCopy duplicates the internal + compression state which can be quite large, so this strategy is slow and + can consume lots of memory. + + deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_STREAM_ERROR if the source stream state was inconsistent + (such as zalloc being NULL). msg is left unchanged in both source and + destination. +*/ + +ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); +/* + This function is equivalent to deflateEnd followed by deflateInit, + but does not free and reallocate all the internal compression state. + The stream will keep the same compression level and any other attributes + that may have been set by deflateInit2. + + deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent (such as zalloc or state being NULL). +*/ + +ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, + int level, + int strategy)); +/* + Dynamically update the compression level and compression strategy. The + interpretation of level and strategy is as in deflateInit2. This can be + used to switch between compression and straight copy of the input data, or + to switch to a different kind of input data requiring a different + strategy. If the compression level is changed, the input available so far + is compressed with the old level (and may be flushed); the new level will + take effect only at the next call of deflate(). + + Before the call of deflateParams, the stream state must be set as for + a call of deflate(), since the currently available input may have to + be compressed and flushed. In particular, strm->avail_out must be non-zero. + + deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source + stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR + if strm->avail_out was zero. +*/ + +ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, + int good_length, + int max_lazy, + int nice_length, + int max_chain)); +/* + Fine tune deflate's internal compression parameters. This should only be + used by someone who understands the algorithm used by zlib's deflate for + searching for the best matching string, and even then only by the most + fanatic optimizer trying to squeeze out the last compressed bit for their + specific input data. Read the deflate.c source code for the meaning of the + max_lazy, good_length, nice_length, and max_chain parameters. + + deflateTune() can be called after deflateInit() or deflateInit2(), and + returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. + */ + +ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, + uLong sourceLen)); +/* + deflateBound() returns an upper bound on the compressed size after + deflation of sourceLen bytes. It must be called after deflateInit() + or deflateInit2(). This would be used to allocate an output buffer + for deflation in a single pass, and so would be called before deflate(). +*/ + +ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, + int bits, + int value)); +/* + deflatePrime() inserts bits in the deflate output stream. The intent + is that this function is used to start off the deflate output with the + bits leftover from a previous deflate stream when appending to it. As such, + this function can only be used for raw deflate, and must be used before the + first deflate() call after a deflateInit2() or deflateReset(). bits must be + less than or equal to 16, and that many of the least significant bits of + value will be inserted in the output. + + deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent. +*/ + +ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, + gz_headerp head)); +/* + deflateSetHeader() provides gzip header information for when a gzip + stream is requested by deflateInit2(). deflateSetHeader() may be called + after deflateInit2() or deflateReset() and before the first call of + deflate(). The text, time, os, extra field, name, and comment information + in the provided gz_header structure are written to the gzip header (xflag is + ignored -- the extra flags are set according to the compression level). The + caller must assure that, if not Z_NULL, name and comment are terminated with + a zero byte, and that if extra is not Z_NULL, that extra_len bytes are + available there. If hcrc is true, a gzip header crc is included. Note that + the current versions of the command-line version of gzip (up through version + 1.3.x) do not support header crc's, and will report that it is a "multi-part + gzip file" and give up. + + If deflateSetHeader is not used, the default gzip header has text false, + the time set to zero, and os set to 255, with no extra, name, or comment + fields. The gzip header is returned to the default state by deflateReset(). + + deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent. +*/ + +/* +ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, + int windowBits)); + + This is another version of inflateInit with an extra parameter. The + fields next_in, avail_in, zalloc, zfree and opaque must be initialized + before by the caller. + + The windowBits parameter is the base two logarithm of the maximum window + size (the size of the history buffer). It should be in the range 8..15 for + this version of the library. The default value is 15 if inflateInit is used + instead. windowBits must be greater than or equal to the windowBits value + provided to deflateInit2() while compressing, or it must be equal to 15 if + deflateInit2() was not used. If a compressed stream with a larger window + size is given as input, inflate() will return with the error code + Z_DATA_ERROR instead of trying to allocate a larger window. + + windowBits can also be -8..-15 for raw inflate. In this case, -windowBits + determines the window size. inflate() will then process raw deflate data, + not looking for a zlib or gzip header, not generating a check value, and not + looking for any check values for comparison at the end of the stream. This + is for use with other formats that use the deflate compressed data format + such as zip. Those formats provide their own check values. If a custom + format is developed using the raw deflate format for compressed data, it is + recommended that a check value such as an adler32 or a crc32 be applied to + the uncompressed data as is done in the zlib, gzip, and zip formats. For + most applications, the zlib format should be used as is. Note that comments + above on the use in deflateInit2() applies to the magnitude of windowBits. + + windowBits can also be greater than 15 for optional gzip decoding. Add + 32 to windowBits to enable zlib and gzip decoding with automatic header + detection, or add 16 to decode only the gzip format (the zlib format will + return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is + a crc32 instead of an adler32. + + inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg + is set to null if there is no error message. inflateInit2 does not perform + any decompression apart from reading the zlib header if present: this will + be done by inflate(). (So next_in and avail_in may be modified, but next_out + and avail_out are unchanged.) +*/ + +ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, + const Bytef *dictionary, + uInt dictLength)); +/* + Initializes the decompression dictionary from the given uncompressed byte + sequence. This function must be called immediately after a call of inflate, + if that call returned Z_NEED_DICT. The dictionary chosen by the compressor + can be determined from the adler32 value returned by that call of inflate. + The compressor and decompressor must use exactly the same dictionary (see + deflateSetDictionary). For raw inflate, this function can be called + immediately after inflateInit2() or inflateReset() and before any call of + inflate() to set the dictionary. The application must insure that the + dictionary that was used for compression is provided. + + inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a + parameter is invalid (such as NULL dictionary) or the stream state is + inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the + expected one (incorrect adler32 value). inflateSetDictionary does not + perform any decompression: this will be done by subsequent calls of + inflate(). +*/ + +ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); +/* + Skips invalid compressed data until a full flush point (see above the + description of deflate with Z_FULL_FLUSH) can be found, or until all + available input is skipped. No output is provided. + + inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR + if no more input was provided, Z_DATA_ERROR if no flush point has been found, + or Z_STREAM_ERROR if the stream structure was inconsistent. In the success + case, the application may save the current current value of total_in which + indicates where valid compressed data was found. In the error case, the + application may repeatedly call inflateSync, providing more input each time, + until success or end of the input data. +*/ + +ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, + z_streamp source)); +/* + Sets the destination stream as a complete copy of the source stream. + + This function can be useful when randomly accessing a large stream. The + first pass through the stream can periodically record the inflate state, + allowing restarting inflate at those points when randomly accessing the + stream. + + inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_STREAM_ERROR if the source stream state was inconsistent + (such as zalloc being NULL). msg is left unchanged in both source and + destination. +*/ + +ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); +/* + This function is equivalent to inflateEnd followed by inflateInit, + but does not free and reallocate all the internal decompression state. + The stream will keep attributes that may have been set by inflateInit2. + + inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent (such as zalloc or state being NULL). +*/ + +ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, + int bits, + int value)); +/* + This function inserts bits in the inflate input stream. The intent is + that this function is used to start inflating at a bit position in the + middle of a byte. The provided bits will be used before any bytes are used + from next_in. This function should only be used with raw inflate, and + should be used before the first inflate() call after inflateInit2() or + inflateReset(). bits must be less than or equal to 16, and that many of the + least significant bits of value will be inserted in the input. + + inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent. +*/ + +ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, + gz_headerp head)); +/* + inflateGetHeader() requests that gzip header information be stored in the + provided gz_header structure. inflateGetHeader() may be called after + inflateInit2() or inflateReset(), and before the first call of inflate(). + As inflate() processes the gzip stream, head->done is zero until the header + is completed, at which time head->done is set to one. If a zlib stream is + being decoded, then head->done is set to -1 to indicate that there will be + no gzip header information forthcoming. Note that Z_BLOCK can be used to + force inflate() to return immediately after header processing is complete + and before any actual data is decompressed. + + The text, time, xflags, and os fields are filled in with the gzip header + contents. hcrc is set to true if there is a header CRC. (The header CRC + was valid if done is set to one.) If extra is not Z_NULL, then extra_max + contains the maximum number of bytes to write to extra. Once done is true, + extra_len contains the actual extra field length, and extra contains the + extra field, or that field truncated if extra_max is less than extra_len. + If name is not Z_NULL, then up to name_max characters are written there, + terminated with a zero unless the length is greater than name_max. If + comment is not Z_NULL, then up to comm_max characters are written there, + terminated with a zero unless the length is greater than comm_max. When + any of extra, name, or comment are not Z_NULL and the respective field is + not present in the header, then that field is set to Z_NULL to signal its + absence. This allows the use of deflateSetHeader() with the returned + structure to duplicate the header. However if those fields are set to + allocated memory, then the application will need to save those pointers + elsewhere so that they can be eventually freed. + + If inflateGetHeader is not used, then the header information is simply + discarded. The header is always checked for validity, including the header + CRC if present. inflateReset() will reset the process to discard the header + information. The application would need to call inflateGetHeader() again to + retrieve the header from the next gzip stream. + + inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent. +*/ + +/* +ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, + unsigned char FAR *window)); + + Initialize the internal stream state for decompression using inflateBack() + calls. The fields zalloc, zfree and opaque in strm must be initialized + before the call. If zalloc and zfree are Z_NULL, then the default library- + derived memory allocation routines are used. windowBits is the base two + logarithm of the window size, in the range 8..15. window is a caller + supplied buffer of that size. Except for special applications where it is + assured that deflate was used with small window sizes, windowBits must be 15 + and a 32K byte window must be supplied to be able to decompress general + deflate streams. + + See inflateBack() for the usage of these routines. + + inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of + the paramaters are invalid, Z_MEM_ERROR if the internal state could not + be allocated, or Z_VERSION_ERROR if the version of the library does not + match the version of the header file. +*/ + +typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); +typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); + +ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, + in_func in, void FAR *in_desc, + out_func out, void FAR *out_desc)); +/* + inflateBack() does a raw inflate with a single call using a call-back + interface for input and output. This is more efficient than inflate() for + file i/o applications in that it avoids copying between the output and the + sliding window by simply making the window itself the output buffer. This + function trusts the application to not change the output buffer passed by + the output function, at least until inflateBack() returns. + + inflateBackInit() must be called first to allocate the internal state + and to initialize the state with the user-provided window buffer. + inflateBack() may then be used multiple times to inflate a complete, raw + deflate stream with each call. inflateBackEnd() is then called to free + the allocated state. + + A raw deflate stream is one with no zlib or gzip header or trailer. + This routine would normally be used in a utility that reads zip or gzip + files and writes out uncompressed files. The utility would decode the + header and process the trailer on its own, hence this routine expects + only the raw deflate stream to decompress. This is different from the + normal behavior of inflate(), which expects either a zlib or gzip header and + trailer around the deflate stream. + + inflateBack() uses two subroutines supplied by the caller that are then + called by inflateBack() for input and output. inflateBack() calls those + routines until it reads a complete deflate stream and writes out all of the + uncompressed data, or until it encounters an error. The function's + parameters and return types are defined above in the in_func and out_func + typedefs. inflateBack() will call in(in_desc, &buf) which should return the + number of bytes of provided input, and a pointer to that input in buf. If + there is no input available, in() must return zero--buf is ignored in that + case--and inflateBack() will return a buffer error. inflateBack() will call + out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() + should return zero on success, or non-zero on failure. If out() returns + non-zero, inflateBack() will return with an error. Neither in() nor out() + are permitted to change the contents of the window provided to + inflateBackInit(), which is also the buffer that out() uses to write from. + The length written by out() will be at most the window size. Any non-zero + amount of input may be provided by in(). + + For convenience, inflateBack() can be provided input on the first call by + setting strm->next_in and strm->avail_in. If that input is exhausted, then + in() will be called. Therefore strm->next_in must be initialized before + calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called + immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in + must also be initialized, and then if strm->avail_in is not zero, input will + initially be taken from strm->next_in[0 .. strm->avail_in - 1]. + + The in_desc and out_desc parameters of inflateBack() is passed as the + first parameter of in() and out() respectively when they are called. These + descriptors can be optionally used to pass any information that the caller- + supplied in() and out() functions need to do their job. + + On return, inflateBack() will set strm->next_in and strm->avail_in to + pass back any unused input that was provided by the last in() call. The + return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR + if in() or out() returned an error, Z_DATA_ERROR if there was a format + error in the deflate stream (in which case strm->msg is set to indicate the + nature of the error), or Z_STREAM_ERROR if the stream was not properly + initialized. In the case of Z_BUF_ERROR, an input or output error can be + distinguished using strm->next_in which will be Z_NULL only if in() returned + an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to + out() returning non-zero. (in() will always be called before out(), so + strm->next_in is assured to be defined if out() returns non-zero.) Note + that inflateBack() cannot return Z_OK. +*/ + +ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); +/* + All memory allocated by inflateBackInit() is freed. + + inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream + state was inconsistent. +*/ + +ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); +/* Return flags indicating compile-time options. + + Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: + 1.0: size of uInt + 3.2: size of uLong + 5.4: size of voidpf (pointer) + 7.6: size of z_off_t + + Compiler, assembler, and debug options: + 8: DEBUG + 9: ASMV or ASMINF -- use ASM code + 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention + 11: 0 (reserved) + + One-time table building (smaller code, but not thread-safe if true): + 12: BUILDFIXED -- build static block decoding tables when needed + 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed + 14,15: 0 (reserved) + + Library content (indicates missing functionality): + 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking + deflate code when not needed) + 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect + and decode gzip streams (to avoid linking crc code) + 18-19: 0 (reserved) + + Operation variations (changes in library functionality): + 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate + 21: FASTEST -- deflate algorithm with only one, lowest compression level + 22,23: 0 (reserved) + + The sprintf variant used by gzprintf (zero is best): + 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format + 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! + 26: 0 = returns value, 1 = void -- 1 means inferred string length returned + + Remainder: + 27-31: 0 (reserved) + */ + + + /* utility functions */ + +/* + The following utility functions are implemented on top of the + basic stream-oriented functions. To simplify the interface, some + default options are assumed (compression level and memory usage, + standard memory allocation functions). The source code of these + utility functions can easily be modified if you need special options. +*/ + +ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, + const Bytef *source, uLong sourceLen)); +/* + Compresses the source buffer into the destination buffer. sourceLen is + the byte length of the source buffer. Upon entry, destLen is the total + size of the destination buffer, which must be at least the value returned + by compressBound(sourceLen). Upon exit, destLen is the actual size of the + compressed buffer. + This function can be used to compress a whole file at once if the + input file is mmap'ed. + compress returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_BUF_ERROR if there was not enough room in the output + buffer. +*/ + +ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen, + const Bytef *source, uLong sourceLen, + int level)); +/* + Compresses the source buffer into the destination buffer. The level + parameter has the same meaning as in deflateInit. sourceLen is the byte + length of the source buffer. Upon entry, destLen is the total size of the + destination buffer, which must be at least the value returned by + compressBound(sourceLen). Upon exit, destLen is the actual size of the + compressed buffer. + + compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_BUF_ERROR if there was not enough room in the output buffer, + Z_STREAM_ERROR if the level parameter is invalid. +*/ + +ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); +/* + compressBound() returns an upper bound on the compressed size after + compress() or compress2() on sourceLen bytes. It would be used before + a compress() or compress2() call to allocate the destination buffer. +*/ + +ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, + const Bytef *source, uLong sourceLen)); +/* + Decompresses the source buffer into the destination buffer. sourceLen is + the byte length of the source buffer. Upon entry, destLen is the total + size of the destination buffer, which must be large enough to hold the + entire uncompressed data. (The size of the uncompressed data must have + been saved previously by the compressor and transmitted to the decompressor + by some mechanism outside the scope of this compression library.) + Upon exit, destLen is the actual size of the compressed buffer. + This function can be used to decompress a whole file at once if the + input file is mmap'ed. + + uncompress returns Z_OK if success, Z_MEM_ERROR if there was not + enough memory, Z_BUF_ERROR if there was not enough room in the output + buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. +*/ + + +typedef voidp gzFile; + +ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); +/* + Opens a gzip (.gz) file for reading or writing. The mode parameter + is as in fopen ("rb" or "wb") but can also include a compression level + ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for + Huffman only compression as in "wb1h", or 'R' for run-length encoding + as in "wb1R". (See the description of deflateInit2 for more information + about the strategy parameter.) + + gzopen can be used to read a file which is not in gzip format; in this + case gzread will directly read from the file without decompression. + + gzopen returns NULL if the file could not be opened or if there was + insufficient memory to allocate the (de)compression state; errno + can be checked to distinguish the two cases (if errno is zero, the + zlib error is Z_MEM_ERROR). */ + +ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); +/* + gzdopen() associates a gzFile with the file descriptor fd. File + descriptors are obtained from calls like open, dup, creat, pipe or + fileno (in the file has been previously opened with fopen). + The mode parameter is as in gzopen. + The next call of gzclose on the returned gzFile will also close the + file descriptor fd, just like fclose(fdopen(fd), mode) closes the file + descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). + gzdopen returns NULL if there was insufficient memory to allocate + the (de)compression state. +*/ + +ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); +/* + Dynamically update the compression level or strategy. See the description + of deflateInit2 for the meaning of these parameters. + gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not + opened for writing. +*/ + +ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); +/* + Reads the given number of uncompressed bytes from the compressed file. + If the input file was not in gzip format, gzread copies the given number + of bytes into the buffer. + gzread returns the number of uncompressed bytes actually read (0 for + end of file, -1 for error). */ + +ZEXTERN int ZEXPORT gzwrite OF((gzFile file, + voidpc buf, unsigned len)); +/* + Writes the given number of uncompressed bytes into the compressed file. + gzwrite returns the number of uncompressed bytes actually written + (0 in case of error). +*/ + +ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); +/* + Converts, formats, and writes the args to the compressed file under + control of the format string, as in fprintf. gzprintf returns the number of + uncompressed bytes actually written (0 in case of error). The number of + uncompressed bytes written is limited to 4095. The caller should assure that + this limit is not exceeded. If it is exceeded, then gzprintf() will return + return an error (0) with nothing written. In this case, there may also be a + buffer overflow with unpredictable consequences, which is possible only if + zlib was compiled with the insecure functions sprintf() or vsprintf() + because the secure snprintf() or vsnprintf() functions were not available. +*/ + +ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); +/* + Writes the given null-terminated string to the compressed file, excluding + the terminating null character. + gzputs returns the number of characters written, or -1 in case of error. +*/ + +ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); +/* + Reads bytes from the compressed file until len-1 characters are read, or + a newline character is read and transferred to buf, or an end-of-file + condition is encountered. The string is then terminated with a null + character. + gzgets returns buf, or Z_NULL in case of error. +*/ + +ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); +/* + Writes c, converted to an unsigned char, into the compressed file. + gzputc returns the value that was written, or -1 in case of error. +*/ + +ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); +/* + Reads one byte from the compressed file. gzgetc returns this byte + or -1 in case of end of file or error. +*/ + +ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); +/* + Push one character back onto the stream to be read again later. + Only one character of push-back is allowed. gzungetc() returns the + character pushed, or -1 on failure. gzungetc() will fail if a + character has been pushed but not read yet, or if c is -1. The pushed + character will be discarded if the stream is repositioned with gzseek() + or gzrewind(). +*/ + +ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); +/* + Flushes all pending output into the compressed file. The parameter + flush is as in the deflate() function. The return value is the zlib + error number (see function gzerror below). gzflush returns Z_OK if + the flush parameter is Z_FINISH and all output could be flushed. + gzflush should be called only when strictly necessary because it can + degrade compression. +*/ + +ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, + z_off_t offset, int whence)); +/* + Sets the starting position for the next gzread or gzwrite on the + given compressed file. The offset represents a number of bytes in the + uncompressed data stream. The whence parameter is defined as in lseek(2); + the value SEEK_END is not supported. + If the file is opened for reading, this function is emulated but can be + extremely slow. If the file is opened for writing, only forward seeks are + supported; gzseek then compresses a sequence of zeroes up to the new + starting position. + + gzseek returns the resulting offset location as measured in bytes from + the beginning of the uncompressed stream, or -1 in case of error, in + particular if the file is opened for writing and the new starting position + would be before the current position. +*/ + +ZEXTERN int ZEXPORT gzrewind OF((gzFile file)); +/* + Rewinds the given file. This function is supported only for reading. + + gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) +*/ + +ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); +/* + Returns the starting position for the next gzread or gzwrite on the + given compressed file. This position represents a number of bytes in the + uncompressed data stream. + + gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) +*/ + +ZEXTERN int ZEXPORT gzeof OF((gzFile file)); +/* + Returns 1 when EOF has previously been detected reading the given + input stream, otherwise zero. +*/ + +ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); +/* + Returns 1 if file is being read directly without decompression, otherwise + zero. +*/ + +ZEXTERN int ZEXPORT gzclose OF((gzFile file)); +/* + Flushes all pending output if necessary, closes the compressed file + and deallocates all the (de)compression state. The return value is the zlib + error number (see function gzerror below). +*/ + +ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); +/* + Returns the error message for the last error which occurred on the + given compressed file. errnum is set to zlib error number. If an + error occurred in the file system and not in the compression library, + errnum is set to Z_ERRNO and the application may consult errno + to get the exact error code. +*/ + +ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); +/* + Clears the error and end-of-file flags for file. This is analogous to the + clearerr() function in stdio. This is useful for continuing to read a gzip + file that is being written concurrently. +*/ + + /* checksum functions */ + +/* + These functions are not related to compression but are exported + anyway because they might be useful in applications using the + compression library. +*/ + +ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); +/* + Update a running Adler-32 checksum with the bytes buf[0..len-1] and + return the updated checksum. If buf is NULL, this function returns + the required initial value for the checksum. + An Adler-32 checksum is almost as reliable as a CRC32 but can be computed + much faster. Usage example: + + uLong adler = adler32(0L, Z_NULL, 0); + + while (read_buffer(buffer, length) != EOF) { + adler = adler32(adler, buffer, length); + } + if (adler != original_adler) error(); +*/ + +ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, + z_off_t len2)); +/* + Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 + and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for + each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of + seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. +*/ + +ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); +/* + Update a running CRC-32 with the bytes buf[0..len-1] and return the + updated CRC-32. If buf is NULL, this function returns the required initial + value for the for the crc. Pre- and post-conditioning (one's complement) is + performed within this function so it shouldn't be done by the application. + Usage example: + + uLong crc = crc32(0L, Z_NULL, 0); + + while (read_buffer(buffer, length) != EOF) { + crc = crc32(crc, buffer, length); + } + if (crc != original_crc) error(); +*/ + +ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); + +/* + Combine two CRC-32 check values into one. For two sequences of bytes, + seq1 and seq2 with lengths len1 and len2, CRC-32 check values were + calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 + check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and + len2. +*/ + + + /* various hacks, don't look :) */ + +/* deflateInit and inflateInit are macros to allow checking the zlib version + * and the compiler's view of z_stream: + */ +ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, + const char *version, int stream_size)); +ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, + const char *version, int stream_size)); +ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method, + int windowBits, int memLevel, + int strategy, const char *version, + int stream_size)); +ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits, + const char *version, int stream_size)); +ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, + unsigned char FAR *window, + const char *version, + int stream_size)); +#define deflateInit(strm, level) \ + deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) +#define inflateInit(strm) \ + inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) +#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ + deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ + (strategy), ZLIB_VERSION, sizeof(z_stream)) +#define inflateInit2(strm, windowBits) \ + inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) +#define inflateBackInit(strm, windowBits, window) \ + inflateBackInit_((strm), (windowBits), (window), \ + ZLIB_VERSION, sizeof(z_stream)) + + +#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) + struct internal_state {int dummy;}; /* hack for buggy compilers */ +#endif + +ZEXTERN const char * ZEXPORT zError OF((int)); +ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z)); +ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); + +#ifdef __cplusplus +} +#endif + +#endif /* ZLIB_H */ diff --git a/cbits/zutil.c b/cbits/zutil.c new file mode 100644 --- /dev/null +++ b/cbits/zutil.c @@ -0,0 +1,318 @@ +/* zutil.c -- target dependent utility functions for the compression library + * Copyright (C) 1995-2005 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id$ */ + +#include "zutil.h" + +#ifndef NO_DUMMY_DECL +struct internal_state {int dummy;}; /* for buggy compilers */ +#endif + +const char * const z_errmsg[10] = { +"need dictionary", /* Z_NEED_DICT 2 */ +"stream end", /* Z_STREAM_END 1 */ +"", /* Z_OK 0 */ +"file error", /* Z_ERRNO (-1) */ +"stream error", /* Z_STREAM_ERROR (-2) */ +"data error", /* Z_DATA_ERROR (-3) */ +"insufficient memory", /* Z_MEM_ERROR (-4) */ +"buffer error", /* Z_BUF_ERROR (-5) */ +"incompatible version",/* Z_VERSION_ERROR (-6) */ +""}; + + +const char * ZEXPORT zlibVersion() +{ + return ZLIB_VERSION; +} + +uLong ZEXPORT zlibCompileFlags() +{ + uLong flags; + + flags = 0; + switch (sizeof(uInt)) { + case 2: break; + case 4: flags += 1; break; + case 8: flags += 2; break; + default: flags += 3; + } + switch (sizeof(uLong)) { + case 2: break; + case 4: flags += 1 << 2; break; + case 8: flags += 2 << 2; break; + default: flags += 3 << 2; + } + switch (sizeof(voidpf)) { + case 2: break; + case 4: flags += 1 << 4; break; + case 8: flags += 2 << 4; break; + default: flags += 3 << 4; + } + switch (sizeof(z_off_t)) { + case 2: break; + case 4: flags += 1 << 6; break; + case 8: flags += 2 << 6; break; + default: flags += 3 << 6; + } +#ifdef DEBUG + flags += 1 << 8; +#endif +#if defined(ASMV) || defined(ASMINF) + flags += 1 << 9; +#endif +#ifdef ZLIB_WINAPI + flags += 1 << 10; +#endif +#ifdef BUILDFIXED + flags += 1 << 12; +#endif +#ifdef DYNAMIC_CRC_TABLE + flags += 1 << 13; +#endif +#ifdef NO_GZCOMPRESS + flags += 1L << 16; +#endif +#ifdef NO_GZIP + flags += 1L << 17; +#endif +#ifdef PKZIP_BUG_WORKAROUND + flags += 1L << 20; +#endif +#ifdef FASTEST + flags += 1L << 21; +#endif +#ifdef STDC +# ifdef NO_vsnprintf + flags += 1L << 25; +# ifdef HAS_vsprintf_void + flags += 1L << 26; +# endif +# else +# ifdef HAS_vsnprintf_void + flags += 1L << 26; +# endif +# endif +#else + flags += 1L << 24; +# ifdef NO_snprintf + flags += 1L << 25; +# ifdef HAS_sprintf_void + flags += 1L << 26; +# endif +# else +# ifdef HAS_snprintf_void + flags += 1L << 26; +# endif +# endif +#endif + return flags; +} + +#ifdef DEBUG + +# ifndef verbose +# define verbose 0 +# endif +int z_verbose = verbose; + +void z_error (m) + char *m; +{ + fprintf(stderr, "%s\n", m); + exit(1); +} +#endif + +/* exported to allow conversion of error code to string for compress() and + * uncompress() + */ +const char * ZEXPORT zError(err) + int err; +{ + return ERR_MSG(err); +} + +#if defined(_WIN32_WCE) + /* The Microsoft C Run-Time Library for Windows CE doesn't have + * errno. We define it as a global variable to simplify porting. + * Its value is always 0 and should not be used. + */ + int errno = 0; +#endif + +#ifndef HAVE_MEMCPY + +void zmemcpy(dest, source, len) + Bytef* dest; + const Bytef* source; + uInt len; +{ + if (len == 0) return; + do { + *dest++ = *source++; /* ??? to be unrolled */ + } while (--len != 0); +} + +int zmemcmp(s1, s2, len) + const Bytef* s1; + const Bytef* s2; + uInt len; +{ + uInt j; + + for (j = 0; j < len; j++) { + if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1; + } + return 0; +} + +void zmemzero(dest, len) + Bytef* dest; + uInt len; +{ + if (len == 0) return; + do { + *dest++ = 0; /* ??? to be unrolled */ + } while (--len != 0); +} +#endif + + +#ifdef SYS16BIT + +#ifdef __TURBOC__ +/* Turbo C in 16-bit mode */ + +# define MY_ZCALLOC + +/* Turbo C malloc() does not allow dynamic allocation of 64K bytes + * and farmalloc(64K) returns a pointer with an offset of 8, so we + * must fix the pointer. Warning: the pointer must be put back to its + * original form in order to free it, use zcfree(). + */ + +#define MAX_PTR 10 +/* 10*64K = 640K */ + +local int next_ptr = 0; + +typedef struct ptr_table_s { + voidpf org_ptr; + voidpf new_ptr; +} ptr_table; + +local ptr_table table[MAX_PTR]; +/* This table is used to remember the original form of pointers + * to large buffers (64K). Such pointers are normalized with a zero offset. + * Since MSDOS is not a preemptive multitasking OS, this table is not + * protected from concurrent access. This hack doesn't work anyway on + * a protected system like OS/2. Use Microsoft C instead. + */ + +voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) +{ + voidpf buf = opaque; /* just to make some compilers happy */ + ulg bsize = (ulg)items*size; + + /* If we allocate less than 65520 bytes, we assume that farmalloc + * will return a usable pointer which doesn't have to be normalized. + */ + if (bsize < 65520L) { + buf = farmalloc(bsize); + if (*(ush*)&buf != 0) return buf; + } else { + buf = farmalloc(bsize + 16L); + } + if (buf == NULL || next_ptr >= MAX_PTR) return NULL; + table[next_ptr].org_ptr = buf; + + /* Normalize the pointer to seg:0 */ + *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4; + *(ush*)&buf = 0; + table[next_ptr++].new_ptr = buf; + return buf; +} + +void zcfree (voidpf opaque, voidpf ptr) +{ + int n; + if (*(ush*)&ptr != 0) { /* object < 64K */ + farfree(ptr); + return; + } + /* Find the original pointer */ + for (n = 0; n < next_ptr; n++) { + if (ptr != table[n].new_ptr) continue; + + farfree(table[n].org_ptr); + while (++n < next_ptr) { + table[n-1] = table[n]; + } + next_ptr--; + return; + } + ptr = opaque; /* just to make some compilers happy */ + Assert(0, "zcfree: ptr not found"); +} + +#endif /* __TURBOC__ */ + + +#ifdef M_I86 +/* Microsoft C in 16-bit mode */ + +# define MY_ZCALLOC + +#if (!defined(_MSC_VER) || (_MSC_VER <= 600)) +# define _halloc halloc +# define _hfree hfree +#endif + +voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) +{ + if (opaque) opaque = 0; /* to make compiler happy */ + return _halloc((long)items, size); +} + +void zcfree (voidpf opaque, voidpf ptr) +{ + if (opaque) opaque = 0; /* to make compiler happy */ + _hfree(ptr); +} + +#endif /* M_I86 */ + +#endif /* SYS16BIT */ + + +#ifndef MY_ZCALLOC /* Any system without a special alloc function */ + +#ifndef STDC +extern voidp malloc OF((uInt size)); +extern voidp calloc OF((uInt items, uInt size)); +extern void free OF((voidpf ptr)); +#endif + +voidpf zcalloc (opaque, items, size) + voidpf opaque; + unsigned items; + unsigned size; +{ + if (opaque) items += size - size; /* make compiler happy */ + return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) : + (voidpf)calloc(items, size); +} + +void zcfree (opaque, ptr) + voidpf opaque; + voidpf ptr; +{ + free(ptr); + if (opaque) return; /* make compiler happy */ +} + +#endif /* MY_ZCALLOC */ diff --git a/zlib.cabal b/zlib.cabal --- a/zlib.cabal +++ b/zlib.cabal @@ -1,17 +1,43 @@ -name: zlib -version: 0.3 -copyright: (c) 2006 Duncan Coutts -build-depends: base -license: BSD3 -author: Duncan Coutts -maintainer: Duncan Coutts -synopsis: Compression and decompression in the gzip and zlib formats -exposed-modules: Codec.Compression.GZip, - Codec.Compression.Zlib, - Codec.Compression.Zlib.Raw, - Codec.Compression.Zlib.Internal -other-modules: Codec.Compression.Zlib.Stream -extensions: ForeignFunctionInterface -includes: zlib.h -extra-libraries: z -ghc-options: -O -fvia-C -Wall +name: zlib +version: 0.4 +copyright: (c) 2006-2007 Duncan Coutts +license: BSD3 +license-file: LICENSE +author: Duncan Coutts +maintainer: Duncan Coutts +synopsis: Compression and decompression in the gzip and zlib formats +stability: provisional +build-type: Simple +cabal-version: >= 1.2.1 + +flag bytestring-in-base + description: In the ghc-6.6 era the bytestring modules were + included in the base package. + +library + exposed-modules: Codec.Compression.GZip, + Codec.Compression.Zlib, + Codec.Compression.Zlib.Raw, + Codec.Compression.Zlib.Internal + other-modules: Codec.Compression.Zlib.Stream + extensions: CPP, ForeignFunctionInterface + if flag(bytestring-in-base) + -- bytestring was in base-2.0 and 2.1.1 + build-depends: base >= 2.0 && < 2.2 + cpp-options: -DBYTESTRING_IN_BASE + else + build-depends: base < 2.0 || >= 2.2, bytestring >= 0.9 + includes: zlib.h + ghc-options: -fvia-C + if !os(windows) + -- Normally we use the the standard system zlib: + extra-libraries: z + else + -- However for the benefit of users of Windows (which does not have zlib + -- by default) we bundle a complete copy of the C sources of zlib-1.2.3 + c-sources: cbits/adler32.c cbits/compress.c cbits/crc32.c + cbits/deflate.c cbits/gzio.c cbits/infback.c + cbits/inffast.c cbits/inflate.c cbits/inftrees.c + cbits/trees.c cbits/uncompr.c cbits/zutil.c + include-dirs: cbits + install-includes: zlib.h