diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,3 @@ +## 0.1.0 + +* Initial release diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,210 @@ + + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. For the purposes of this definition, + "control" means (i) the power, direct or indirect, to cause the + direction or management of such entity, whether by contract or + otherwise, or (ii) ownership of fifty percent (50%) or more of the + outstanding shares, or (iii) beneficial ownership of such entity. + + "You" (or "Your") shall mean an individual or Legal Entity + exercising permissions granted by this License. + + "Source" form shall mean the preferred form for making modifications, + including but not limited to software source code, documentation + source, and configuration files. + + "Object" form shall mean any form resulting from mechanical + transformation or translation of a Source form, including but + not limited to compiled object code, generated documentation, + and conversions to other media types. + + "Work" shall mean the work of authorship, whether in Source or + Object form, made available under the License, as indicated by a + copyright notice that is included in or attached to the work. + + "Derivative Works" shall mean any work, whether in Source or Object + form, that is based on (or derived from) the Work and for which the + editorial revisions, annotations, elaborations, or other modifications + represent, as a whole, an original work of authorship. For the purposes + of this License, Derivative Works shall not include works that remain + separable from, or merely link (or bind by name) to the interfaces of, + the Work and Derivative Works thereof. + + "Contribution" shall mean any work of authorship, including + the original version of the Work and any modifications or additions + to that Work or Derivative Works thereof, that is intentionally + submitted to Licensor for inclusion in the Work by the copyright owner + or by an individual or Legal Entity authorized to submit on behalf of + the copyright owner. For the purposes of this definition, "submitted" + means any form of electronic, verbal, or written communication sent + to the Licensor or its representatives, including but not limited to + communication on electronic mailing lists, source code control systems, + and issue tracking systems that are managed by, or on behalf of, the + Licensor for the purpose of discussing and improving the Work, but + excluding communication that is conspicuously marked or otherwise + designated in writing by the copyright owner as "Not a Contribution." + + "Contributor" shall mean Licensor and any individual or Legal Entity + on behalf of whom a Contribution has been received by Licensor and + subsequently incorporated within the Work. + + 2. Grant of Copyright License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + copyright license to reproduce, prepare Derivative Works of, + publicly display, publicly perform, sublicense, and distribute the + Work and such Derivative Works in Source or Object form. + + 3. Grant of Patent License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + (except as stated in this section) patent license to make, have made, + use, offer to sell, sell, import, and otherwise transfer the Work, + where such license applies only to those patent claims licensable + by such Contributor that are necessarily infringed by their + Contribution(s) alone or by combination of their Contribution(s) + with the Work to which such Contribution(s) was submitted. If You + institute patent litigation against any entity (including a + cross-claim or counterclaim in a lawsuit) alleging that the Work + or a Contribution incorporated within the Work constitutes direct + or contributory patent infringement, then any patent licenses + granted to You under this License for that Work shall terminate + as of the date such litigation is filed. + + 4. Redistribution. You may reproduce and distribute copies of the + Work or Derivative Works thereof in any medium, with or without + modifications, and in Source or Object form, provided that You + meet the following conditions: + + (a) You must give any other recipients of the Work or + Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices + stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works + that You distribute, all copyright, patent, trademark, and + attribution notices from the Source form of the Work, + excluding those notices that do not pertain to any part of + the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its + distribution, then any Derivative Works that You distribute must + include a readable copy of the attribution notices contained + within such NOTICE file, excluding those notices that do not + pertain to any part of the Derivative Works, in at least one + of the following places: within a NOTICE text file distributed + as part of the Derivative Works; within the Source form or + documentation, if provided along with the Derivative Works; or, + within a display generated by the Derivative Works, if and + wherever such third-party notices normally appear. The contents + of the NOTICE file are for informational purposes only and + do not modify the License. You may add Your own attribution + notices within Derivative Works that You distribute, alongside + or as an addendum to the NOTICE text from the Work, provided + that such additional attribution notices cannot be construed + as modifying the License. + + You may add Your own copyright statement to Your modifications and + may provide additional or different license terms and conditions + for use, reproduction, or distribution of Your modifications, or + for any such Derivative Works as a whole, provided Your use, + reproduction, and distribution of the Work otherwise complies with + the conditions stated in this License. + + 5. Submission of Contributions. Unless You explicitly state otherwise, + any Contribution intentionally submitted for inclusion in the Work + by You to the Licensor shall be under the terms and conditions of + this License, without any additional terms or conditions. + Notwithstanding the above, nothing herein shall supersede or modify + the terms of any separate license agreement you may have executed + with Licensor regarding such Contributions. + + 6. Trademarks. This License does not grant permission to use the trade + names, trademarks, service marks, or product names of the Licensor, + except as required for reasonable and customary use in describing the + origin of the Work and reproducing the content of the NOTICE file. + + 7. Disclaimer of Warranty. Unless required by applicable law or + agreed to in writing, Licensor provides the Work (and each + Contributor provides its Contributions) on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or + implied, including, without limitation, any warranties or conditions + of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A + PARTICULAR PURPOSE. You are solely responsible for determining the + appropriateness of using or redistributing the Work and assume any + risks associated with Your exercise of permissions under this License. + + 8. Limitation of Liability. In no event and under no legal theory, + whether in tort (including negligence), contract, or otherwise, + unless required by applicable law (such as deliberate and grossly + negligent acts) or agreed to in writing, shall any Contributor be + liable to You for damages, including any direct, indirect, special, + incidental, or consequential damages of any character arising as a + result of this License or out of the use or inability to use the + Work (including but not limited to damages for loss of goodwill, + work stoppage, computer failure or malfunction, or any and all + other commercial damages or losses), even if such Contributor + has been advised of the possibility of such damages. + + 9. Accepting Warranty or Additional Liability. While redistributing + the Work or Derivative Works thereof, You may choose to offer, + and charge a fee for, acceptance of support, warranty, indemnity, + or other liability obligations and/or rights consistent with this + License. However, in accepting such obligations, You may act only + on Your own behalf and on Your sole responsibility, not on behalf + of any other Contributor, and only if You agree to indemnify, + defend, and hold each Contributor harmless for any liability + incurred by, or claims asserted against, such Contributor by reason + of your accepting any such warranty or additional liability. + + END OF TERMS AND CONDITIONS + +------------------------------------------------------------------------------- +All the files under the direcotry c/ are copied from the LZ4 library. Below is +the LICENSE for those files. +------------------------------------------------------------------------------- + +LZ4 Library +Copyright (c) 2011-present, Yann Collet +All rights reserved. + +Redistribution and use in source and binary forms, with or without modification, +are permitted provided that the following conditions are met: + +* Redistributions of source code must retain the above copyright notice, this + list of conditions and the following disclaimer. + +* 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 HOLDER 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. + + You can contact the author at : + - LZ4 homepage : http://www.lz4.org + - LZ4 source repository : https://github.com/lz4/lz4 diff --git a/NOTICE b/NOTICE new file mode 100644 --- /dev/null +++ b/NOTICE @@ -0,0 +1,5 @@ +streamly-lz4 +Copyright 2020 Composewell Technologies and Contributors + +This product includes software developed at +Composewell Technologies (http://www.composewell.com). diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,51 @@ +# streamly-lz4 + +This library uses the LZ4 compression algorithm + to compress and decompress a data stream +using [Haskell Streamly](https://streamly.composewell.com/). + +## Running benchmarks + +`download-corpora.sh` downloads and unpacks the [caterbury +corpus](https://corpus.canterbury.ac.nz/) used for benchmarking. + +Run the following commands from the top level directory in the repo: +``` +$ ./download-corpora.sh +$ cabal run bench-lz4 -- --quick +``` + +To use [fusion-plugin](https://github.com/composewell/fusion-plugin) for +benchmarks: + +``` +$ cabal run --flag fusion-plugin bench-lz4 -- --quick +``` + +### Benchmarking an external corpus + +`BENCH_STREAMLY_LZ4_FILE` is looked up for file to benchmark. This should +contain the absolute path of the target file. + +`BENCH_STREAMLY_LZ4_STRATEGY` is looked up for which benchmarking combinator to +run on the target file. + +It can contain values of the following structure, +- `c+speed+bufsize` +- `d+bufsize` +- `r+bufsize` + +`c` corresponds to compress, `d` for decompress and `r` for resizing. + +Example, +``` +$ export BENCH_STREAMLY_LZ4_FILE="path/to/file/" +$ export BENCH_STREAMLY_LZ4_STRATEGY="c+400+640000" +$ cabal bench +``` + +The commands above runs the compression bench suite on **path/to/file/** with +the acceleration value of **500** read as arrays of size **640000** bytes. + +*Note*: For the decompression and resizing bench suite a compressed file is +expected as input. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/benchmark/Main.hs b/benchmark/Main.hs new file mode 100644 --- /dev/null +++ b/benchmark/Main.hs @@ -0,0 +1,315 @@ +-- | +-- Module : Streamly.Internal.LZ4.Config +-- Copyright : (c) 2020 Composewell Technologies +-- License : Apache-2.0 +-- Maintainer : streamly@composewell.com +-- Stability : experimental +-- Portability : GHC +-- +module Main (main) where + +import Control.Monad (unless) +import Data.Semigroup (cycle1) +import Data.Word (Word8) +import Data.Function ((&)) +import Streamly.Internal.Data.Array.Foreign (Array) +import Streamly.Internal.Data.Stream.StreamD (fromStreamD, toStreamD) +import Streamly.Prelude (SerialT) +import System.Directory (getCurrentDirectory, doesFileExist) +import System.Environment (lookupEnv) + +import qualified Streamly.Internal.Data.Stream.IsStream as Stream +import qualified Streamly.Internal.Data.Array.Foreign as Array +import qualified Streamly.Internal.FileSystem.File as File +import qualified Streamly.Internal.LZ4 as LZ4 +import qualified Streamly.Internal.LZ4.Config as LZ4 +import qualified Streamly.LZ4 as LZ4 + +import Gauge.Main + +{-# INLINE _64KB #-} +_64KB :: Int +_64KB = 64 * 1024 + +{-# INLINE _10MB #-} +_10MB :: Int +_10MB = 10 * 1024 * 1024 + +-------------------------------------------------------------------------------- +-- Corpora helpers +-------------------------------------------------------------------------------- + +{-# INLINE large_bible_txt #-} +large_bible_txt :: String +large_bible_txt = "large/bible.txt" + +{-# INLINE large_world192_txt #-} +large_world192_txt :: String +large_world192_txt = "large/world192.txt" + +{-# INLINE cantrbry_alice29_txt #-} +cantrbry_alice29_txt :: String +cantrbry_alice29_txt = "cantrbry/alice29.txt" + +-------------------------------------------------------------------------------- +-- Bootstrapping +-------------------------------------------------------------------------------- + +normalizedName :: String -> String +normalizedName x = x ++ ".normalized" + +bigCompressedName :: String -> String +bigCompressedName x = x ++ ".normalized.compressed.big" + +smallCompressedName :: String -> String +smallCompressedName x = x ++ ".normalized.compressed.small" + +withCompressedName :: String -> String +withCompressedName x = x ++ ".normalized.compressed.frame" + +bootstrap :: String -> IO () +bootstrap fp = do + let normalizedFp = normalizedName fp + compressedFpBig = bigCompressedName fp + compressedFpSmall = smallCompressedName fp + compressedWith = withCompressedName fp + fileExists <- doesFileExist normalizedFp + unless fileExists $ do + putStrLn $ "Normalizing " ++ fp + let fileStream = Stream.unfold File.read fp + combinedStream = + Stream.arraysOf _64KB + $ Stream.take _10MB + $ cycle1 fileStream + combinedStream & File.fromChunks normalizedFp + combinedStream & LZ4.compressChunks LZ4.defaultBlockConfig 65537 + & File.fromChunks compressedFpBig + combinedStream & LZ4.compressChunks LZ4.defaultBlockConfig 1 + & File.fromChunks compressedFpSmall + -- Stream with header that returns the config + -- Magic Little endian (4 bytes) = 407708164 + let magicLE = [4, 34, 77, 24] + -- flg with everything unset + flg = 64 + -- bd with 64KB block max size + bd = 64 + headerChk = 0 + headerList = magicLE ++ [flg, bd, headerChk] + header = Stream.fromList headerList + headerArr <- Stream.fold (Array.writeN (length headerList)) header + (bf, ff) <- Stream.parseD LZ4.simpleFrameParserD header + combinedStream & compressChunksFrame bf ff 65537 + & Stream.cons headerArr + & File.fromChunks compressedWith + + where + + {-# INLINE endMarkArr #-} + endMarkArr :: Array.Array Word8 + endMarkArr = Array.fromListN 4 [0,0,0,0] + + compressChunksFrame + :: LZ4.BlockConfig + -> LZ4.FrameConfig + -> Int + -> Stream.SerialT IO (Array.Array Word8) + -> Stream.SerialT IO (Array.Array Word8) + compressChunksFrame bf ff i_ strm = + if LZ4.hasEndMark ff + then (fromStreamD . LZ4.compressChunksD bf i_ . toStreamD) strm + `Stream.append` Stream.fromPure endMarkArr + else (fromStreamD . LZ4.compressChunksD bf i_ . toStreamD) strm + + +-------------------------------------------------------------------------------- +-- Benchmark helpers +-------------------------------------------------------------------------------- + +type Combinator = SerialT IO (Array Word8) -> SerialT IO (Array Word8) + +{-# INLINE benchCorpus #-} +benchCorpus :: Int -> String -> String -> Combinator -> Benchmark +benchCorpus bufsize name corpus combinator = + let bname = ("bufsize(" ++ show bufsize ++ ")/" ++ name ++ "/" ++ corpus) + in bench bname $ nfIO $ do + Stream.unfold File.readChunksWithBufferOf (bufsize, corpus) + & combinator + & Stream.drain + +-------------------------------------------------------------------------------- +-- Benchmarks +-------------------------------------------------------------------------------- + +{-# INLINE compress #-} +compress :: Int -> Int -> String -> Benchmark +compress bufsize i corpus = + benchCorpus bufsize ("compress " ++ show i) corpus + $ LZ4.compressChunks LZ4.defaultBlockConfig i + +{-# INLINE decompress #-} +decompress :: Int -> String -> Benchmark +decompress bufsize corpus = + benchCorpus bufsize "decompress" corpus + $ LZ4.decompressChunks LZ4.defaultBlockConfig + +{-# INLINE decompressWith #-} +decompressWith :: Int -> String -> Benchmark +decompressWith bufsize corpus = + benchCorpus bufsize "decompressWith" corpus + $ fromStreamD + . LZ4.decompressChunksWithD LZ4.simpleFrameParserD . toStreamD + +{-# INLINE resize #-} +resize :: Int -> String -> Benchmark +resize bufsize corpus = + benchCorpus bufsize "resize" corpus + $ fromStreamD + . LZ4.resizeChunksD LZ4.defaultBlockConfig LZ4.defaultFrameConfig + . toStreamD + +-------------------------------------------------------------------------------- +-- Reading environment +-------------------------------------------------------------------------------- + +-- Environment variables looked up +-- BENCH_STREAMLY_LZ4_FILE +-- BENCH_STREAMLY_LZ4_STRATEGY +-- - c+speed+buffer +-- - d+buffer +-- - r+buffer +-- +-- Example: +-- > export BENCH_STREAMLY_LZ4_FILE="path/to/file/" +-- > export BENCH_STREAMLY_LZ4_STRATEGY="c+400+640000" +-- > cabal bench +-- +-- The above commands will benchmark file on compression with acceleration value +-- of 400 and buffer size of 640000 + +data Strategy + = Compress Int Int + | Decompress Int + | Resize Int + +{-# INLINE parseStrategy #-} +parseStrategy :: String -> Strategy +parseStrategy ('c':_:r) = + let (speed, pbufsize) = span (/= '+') r + in Compress (read speed) (read (tail pbufsize)) +parseStrategy ('d':_:r) = Decompress (read r) +parseStrategy ('r':_:r) = Resize (read r) +parseStrategy _ = error "Cannot parse BENCH_STREAMLY_LZ4_STRATEGY" + +{-# INLINE runStrategy #-} +runStrategy :: String -> Strategy -> Benchmark +runStrategy file (Compress speed bufsize) = compress bufsize speed file +runStrategy file (Decompress bufsize) = decompress bufsize file +runStrategy file (Resize bufsize) = resize bufsize file + +{-# INLINE tryBenchExternal #-} +tryBenchExternal :: IO (Maybe Benchmark) +tryBenchExternal = do + fr <- lookupEnv "BENCH_STREAMLY_LZ4_FILE" + case fr of + Nothing -> return Nothing + Just file -> do + fs <- lookupEnv "BENCH_STREAMLY_LZ4_STRATEGY" + return + $ case fs of + Nothing -> Nothing + Just s -> Just $ runStrategy file (parseStrategy s) + +-------------------------------------------------------------------------------- +-- Main +-------------------------------------------------------------------------------- + +main :: IO () +main = do + base <- flip (++) "/corpora/" <$> getCurrentDirectory + let rel f = base ++ f + relNormalized f = normalizedName (base ++ f) + relBigCompressed f = bigCompressedName (base ++ f) + relWithCompressed f = withCompressedName (base ++ f) + relSmallCompressed f = smallCompressedName (base ++ f) + bootstrap (rel large_bible_txt) + bootstrap (rel large_world192_txt) + bootstrap (rel cantrbry_alice29_txt) + external <- maybe [] (: []) <$> tryBenchExternal + defaultMain $ + external ++ + [ compression_files relNormalized + , decompression_files_big relBigCompressed + , decompression_files_with relWithCompressed + , decompression_files_small relSmallCompressed + , compression_accelaration relNormalized + , compression_buffer relNormalized + , decompression_buffer relBigCompressed + , resizing_buffer relBigCompressed + ] + + where + + compression_files f = + bgroup + "compress/files" + [ compress _64KB 5 (f large_bible_txt) + , compress _64KB 5 (f large_world192_txt) + , compress _64KB 5 (f cantrbry_alice29_txt) + ] + + decompression_files_big f = + bgroup + "decompress/files/big" + [ decompress _64KB (f large_bible_txt) + , decompress _64KB (f large_world192_txt) + , decompress _64KB (f cantrbry_alice29_txt) + ] + + decompression_files_with f = + bgroup + "decompressWith" + [ decompressWith _64KB (f large_bible_txt) + , decompressWith _64KB (f large_world192_txt) + , decompressWith _64KB (f cantrbry_alice29_txt) + ] + + decompression_files_small f = + bgroup + "decompression/files/small" + [ decompress _64KB (f large_bible_txt) + , decompress _64KB (f large_world192_txt) + , decompress _64KB (f cantrbry_alice29_txt) + ] + + compression_accelaration f = + bgroup + "compression/acceleration" + [ compress _64KB (-1) (f large_bible_txt) + , compress _64KB 10 (f large_bible_txt) + , compress _64KB 1000 (f large_bible_txt) + , compress _64KB 65537 (f large_bible_txt) + ] + + compression_buffer f = + bgroup + "compression/buffer" + [ compress (_64KB `div` 10) 5 (f large_bible_txt) + , compress _64KB 5 (f large_bible_txt) + , compress (_64KB * 10) 5 (f large_bible_txt) + ] + + decompression_buffer f = + bgroup + "decompression/buffer" + [ decompress (_64KB `div` 10) (f large_bible_txt) + , decompress _64KB (f large_bible_txt) + , decompress (_64KB * 10) (f large_bible_txt) + ] + + resizing_buffer f = + bgroup + "resizing/buffer" + [ resize (_64KB `div` 10) (f large_bible_txt) + , resize _64KB (f large_bible_txt) + , resize (_64KB * 10) (f large_bible_txt) + ] diff --git a/cbits/lz4.c b/cbits/lz4.c new file mode 100644 --- /dev/null +++ b/cbits/lz4.c @@ -0,0 +1,2495 @@ +/* + LZ4 - Fast LZ compression algorithm + Copyright (C) 2011-present, Yann Collet. + + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * 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. + + You can contact the author at : + - LZ4 homepage : http://www.lz4.org + - LZ4 source repository : https://github.com/lz4/lz4 +*/ + +/*-************************************ +* Tuning parameters +**************************************/ +/* + * LZ4_HEAPMODE : + * Select how default compression functions will allocate memory for their hash table, + * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()). + */ +#ifndef LZ4_HEAPMODE +# define LZ4_HEAPMODE 0 +#endif + +/* + * LZ4_ACCELERATION_DEFAULT : + * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0 + */ +#define LZ4_ACCELERATION_DEFAULT 1 +/* + * LZ4_ACCELERATION_MAX : + * Any "acceleration" value higher than this threshold + * get treated as LZ4_ACCELERATION_MAX instead (fix #876) + */ +#define LZ4_ACCELERATION_MAX 65537 + + +/*-************************************ +* CPU Feature Detection +**************************************/ +/* LZ4_FORCE_MEMORY_ACCESS + * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. + * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. + * The below switch allow to select different access method for improved performance. + * Method 0 (default) : use `memcpy()`. Safe and portable. + * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). + * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. + * Method 2 : direct access. This method is portable but violate C standard. + * It can generate buggy code on targets which assembly generation depends on alignment. + * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) + * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. + * Prefer these methods in priority order (0 > 1 > 2) + */ +#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */ +# if defined(__GNUC__) && \ + ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) \ + || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) +# define LZ4_FORCE_MEMORY_ACCESS 2 +# elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__) +# define LZ4_FORCE_MEMORY_ACCESS 1 +# endif +#endif + +/* + * LZ4_FORCE_SW_BITCOUNT + * Define this parameter if your target system or compiler does not support hardware bit count + */ +#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */ +# undef LZ4_FORCE_SW_BITCOUNT /* avoid double def */ +# define LZ4_FORCE_SW_BITCOUNT +#endif + + + +/*-************************************ +* Dependency +**************************************/ +/* + * LZ4_SRC_INCLUDED: + * Amalgamation flag, whether lz4.c is included + */ +#ifndef LZ4_SRC_INCLUDED +# define LZ4_SRC_INCLUDED 1 +#endif + +#ifndef LZ4_STATIC_LINKING_ONLY +#define LZ4_STATIC_LINKING_ONLY +#endif + +#ifndef LZ4_DISABLE_DEPRECATE_WARNINGS +#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */ +#endif + +#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */ +#include "lz4.h" +/* see also "memory routines" below */ + + +/*-************************************ +* Compiler Options +**************************************/ +#if defined(_MSC_VER) && (_MSC_VER >= 1400) /* Visual Studio 2005+ */ +# include /* only present in VS2005+ */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +#endif /* _MSC_VER */ + +#ifndef LZ4_FORCE_INLINE +# ifdef _MSC_VER /* Visual Studio */ +# define LZ4_FORCE_INLINE static __forceinline +# else +# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# ifdef __GNUC__ +# define LZ4_FORCE_INLINE static inline __attribute__((always_inline)) +# else +# define LZ4_FORCE_INLINE static inline +# endif +# else +# define LZ4_FORCE_INLINE static +# endif /* __STDC_VERSION__ */ +# endif /* _MSC_VER */ +#endif /* LZ4_FORCE_INLINE */ + +/* LZ4_FORCE_O2 and LZ4_FORCE_INLINE + * gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy8, + * together with a simple 8-byte copy loop as a fall-back path. + * However, this optimization hurts the decompression speed by >30%, + * because the execution does not go to the optimized loop + * for typical compressible data, and all of the preamble checks + * before going to the fall-back path become useless overhead. + * This optimization happens only with the -O3 flag, and -O2 generates + * a simple 8-byte copy loop. + * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy8 + * functions are annotated with __attribute__((optimize("O2"))), + * and also LZ4_wildCopy8 is forcibly inlined, so that the O2 attribute + * of LZ4_wildCopy8 does not affect the compression speed. + */ +#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__) && !defined(__clang__) +# define LZ4_FORCE_O2 __attribute__((optimize("O2"))) +# undef LZ4_FORCE_INLINE +# define LZ4_FORCE_INLINE static __inline __attribute__((optimize("O2"),always_inline)) +#else +# define LZ4_FORCE_O2 +#endif + +#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__) +# define expect(expr,value) (__builtin_expect ((expr),(value)) ) +#else +# define expect(expr,value) (expr) +#endif + +#ifndef likely +#define likely(expr) expect((expr) != 0, 1) +#endif +#ifndef unlikely +#define unlikely(expr) expect((expr) != 0, 0) +#endif + +/* Should the alignment test prove unreliable, for some reason, + * it can be disabled by setting LZ4_ALIGN_TEST to 0 */ +#ifndef LZ4_ALIGN_TEST /* can be externally provided */ +# define LZ4_ALIGN_TEST 1 +#endif + + +/*-************************************ +* Memory routines +**************************************/ +#ifdef LZ4_USER_MEMORY_FUNCTIONS +/* memory management functions can be customized by user project. + * Below functions must exist somewhere in the Project + * and be available at link time */ +void* LZ4_malloc(size_t s); +void* LZ4_calloc(size_t n, size_t s); +void LZ4_free(void* p); +# define ALLOC(s) LZ4_malloc(s) +# define ALLOC_AND_ZERO(s) LZ4_calloc(1,s) +# define FREEMEM(p) LZ4_free(p) +#else +# include /* malloc, calloc, free */ +# define ALLOC(s) malloc(s) +# define ALLOC_AND_ZERO(s) calloc(1,s) +# define FREEMEM(p) free(p) +#endif + +#include /* memset, memcpy */ +#define MEM_INIT(p,v,s) memset((p),(v),(s)) + + +/*-************************************ +* Common Constants +**************************************/ +#define MINMATCH 4 + +#define WILDCOPYLENGTH 8 +#define LASTLITERALS 5 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ +#define MFLIMIT 12 /* see ../doc/lz4_Block_format.md#parsing-restrictions */ +#define MATCH_SAFEGUARD_DISTANCE ((2*WILDCOPYLENGTH) - MINMATCH) /* ensure it's possible to write 2 x wildcopyLength without overflowing output buffer */ +#define FASTLOOP_SAFE_DISTANCE 64 +static const int LZ4_minLength = (MFLIMIT+1); + +#define KB *(1 <<10) +#define MB *(1 <<20) +#define GB *(1U<<30) + +#define LZ4_DISTANCE_ABSOLUTE_MAX 65535 +#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */ +# error "LZ4_DISTANCE_MAX is too big : must be <= 65535" +#endif + +#define ML_BITS 4 +#define ML_MASK ((1U<=1) +# include +#else +# ifndef assert +# define assert(condition) ((void)0) +# endif +#endif + +#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use after variable declarations */ + +#if defined(LZ4_DEBUG) && (LZ4_DEBUG>=2) +# include + static int g_debuglog_enable = 1; +# define DEBUGLOG(l, ...) { \ + if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \ + fprintf(stderr, __FILE__ ": "); \ + fprintf(stderr, __VA_ARGS__); \ + fprintf(stderr, " \n"); \ + } } +#else +# define DEBUGLOG(l, ...) {} /* disabled */ +#endif + +static int LZ4_isAligned(const void* ptr, size_t alignment) +{ + return ((size_t)ptr & (alignment -1)) == 0; +} + + +/*-************************************ +* Types +**************************************/ +#include +#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +# include + typedef uint8_t BYTE; + typedef uint16_t U16; + typedef uint32_t U32; + typedef int32_t S32; + typedef uint64_t U64; + typedef uintptr_t uptrval; +#else +# if UINT_MAX != 4294967295UL +# error "LZ4 code (when not C++ or C99) assumes that sizeof(int) == 4" +# endif + typedef unsigned char BYTE; + typedef unsigned short U16; + typedef unsigned int U32; + typedef signed int S32; + typedef unsigned long long U64; + typedef size_t uptrval; /* generally true, except OpenVMS-64 */ +#endif + +#if defined(__x86_64__) + typedef U64 reg_t; /* 64-bits in x32 mode */ +#else + typedef size_t reg_t; /* 32-bits in x32 mode */ +#endif + +typedef enum { + notLimited = 0, + limitedOutput = 1, + fillOutput = 2 +} limitedOutput_directive; + + +/*-************************************ +* Reading and writing into memory +**************************************/ + +/** + * LZ4 relies on memcpy with a constant size being inlined. In freestanding + * environments, the compiler can't assume the implementation of memcpy() is + * standard compliant, so it can't apply its specialized memcpy() inlining + * logic. When possible, use __builtin_memcpy() to tell the compiler to analyze + * memcpy() as if it were standard compliant, so it can inline it in freestanding + * environments. This is needed when decompressing the Linux Kernel, for example. + */ +#if defined(__GNUC__) && (__GNUC__ >= 4) +#define LZ4_memcpy(dst, src, size) __builtin_memcpy(dst, src, size) +#else +#define LZ4_memcpy(dst, src, size) memcpy(dst, src, size) +#endif + +static unsigned LZ4_isLittleEndian(void) +{ + const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ + return one.c[0]; +} + + +#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2) +/* lie to the compiler about data alignment; use with caution */ + +static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; } +static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; } +static reg_t LZ4_read_ARCH(const void* memPtr) { return *(const reg_t*) memPtr; } + +static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; } +static void LZ4_write32(void* memPtr, U32 value) { *(U32*)memPtr = value; } + +#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1) + +/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ +/* currently only defined for gcc and icc */ +typedef union { U16 u16; U32 u32; reg_t uArch; } __attribute__((packed)) unalign; + +static U16 LZ4_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } +static U32 LZ4_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } +static reg_t LZ4_read_ARCH(const void* ptr) { return ((const unalign*)ptr)->uArch; } + +static void LZ4_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; } +static void LZ4_write32(void* memPtr, U32 value) { ((unalign*)memPtr)->u32 = value; } + +#else /* safe and portable access using memcpy() */ + +static U16 LZ4_read16(const void* memPtr) +{ + U16 val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static U32 LZ4_read32(const void* memPtr) +{ + U32 val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static reg_t LZ4_read_ARCH(const void* memPtr) +{ + reg_t val; LZ4_memcpy(&val, memPtr, sizeof(val)); return val; +} + +static void LZ4_write16(void* memPtr, U16 value) +{ + LZ4_memcpy(memPtr, &value, sizeof(value)); +} + +static void LZ4_write32(void* memPtr, U32 value) +{ + LZ4_memcpy(memPtr, &value, sizeof(value)); +} + +#endif /* LZ4_FORCE_MEMORY_ACCESS */ + + +static U16 LZ4_readLE16(const void* memPtr) +{ + if (LZ4_isLittleEndian()) { + return LZ4_read16(memPtr); + } else { + const BYTE* p = (const BYTE*)memPtr; + return (U16)((U16)p[0] + (p[1]<<8)); + } +} + +static void LZ4_writeLE16(void* memPtr, U16 value) +{ + if (LZ4_isLittleEndian()) { + LZ4_write16(memPtr, value); + } else { + BYTE* p = (BYTE*)memPtr; + p[0] = (BYTE) value; + p[1] = (BYTE)(value>>8); + } +} + +/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */ +LZ4_FORCE_INLINE +void LZ4_wildCopy8(void* dstPtr, const void* srcPtr, void* dstEnd) +{ + BYTE* d = (BYTE*)dstPtr; + const BYTE* s = (const BYTE*)srcPtr; + BYTE* const e = (BYTE*)dstEnd; + + do { LZ4_memcpy(d,s,8); d+=8; s+=8; } while (d= 16. */ +LZ4_FORCE_INLINE void +LZ4_wildCopy32(void* dstPtr, const void* srcPtr, void* dstEnd) +{ + BYTE* d = (BYTE*)dstPtr; + const BYTE* s = (const BYTE*)srcPtr; + BYTE* const e = (BYTE*)dstEnd; + + do { LZ4_memcpy(d,s,16); LZ4_memcpy(d+16,s+16,16); d+=32; s+=32; } while (d= dstPtr + MINMATCH + * - there is at least 8 bytes available to write after dstEnd */ +LZ4_FORCE_INLINE void +LZ4_memcpy_using_offset(BYTE* dstPtr, const BYTE* srcPtr, BYTE* dstEnd, const size_t offset) +{ + BYTE v[8]; + + assert(dstEnd >= dstPtr + MINMATCH); + + switch(offset) { + case 1: + MEM_INIT(v, *srcPtr, 8); + break; + case 2: + LZ4_memcpy(v, srcPtr, 2); + LZ4_memcpy(&v[2], srcPtr, 2); + LZ4_memcpy(&v[4], v, 4); + break; + case 4: + LZ4_memcpy(v, srcPtr, 4); + LZ4_memcpy(&v[4], srcPtr, 4); + break; + default: + LZ4_memcpy_using_offset_base(dstPtr, srcPtr, dstEnd, offset); + return; + } + + LZ4_memcpy(dstPtr, v, 8); + dstPtr += 8; + while (dstPtr < dstEnd) { + LZ4_memcpy(dstPtr, v, 8); + dstPtr += 8; + } +} +#endif + + +/*-************************************ +* Common functions +**************************************/ +static unsigned LZ4_NbCommonBytes (reg_t val) +{ + assert(val != 0); + if (LZ4_isLittleEndian()) { + if (sizeof(val) == 8) { +# if defined(_MSC_VER) && (_MSC_VER >= 1800) && defined(_M_AMD64) && !defined(LZ4_FORCE_SW_BITCOUNT) + /* x64 CPUS without BMI support interpret `TZCNT` as `REP BSF` */ + return (unsigned)_tzcnt_u64(val) >> 3; +# elif defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r = 0; + _BitScanForward64(&r, (U64)val); + return (unsigned)r >> 3; +# elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_ctzll((U64)val) >> 3; +# else + const U64 m = 0x0101010101010101ULL; + val ^= val - 1; + return (unsigned)(((U64)((val & (m - 1)) * m)) >> 56); +# endif + } else /* 32 bits */ { +# if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r; + _BitScanForward(&r, (U32)val); + return (unsigned)r >> 3; +# elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_ctz((U32)val) >> 3; +# else + const U32 m = 0x01010101; + return (unsigned)((((val - 1) ^ val) & (m - 1)) * m) >> 24; +# endif + } + } else /* Big Endian CPU */ { + if (sizeof(val)==8) { +# if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_clzll((U64)val) >> 3; +# else +#if 1 + /* this method is probably faster, + * but adds a 128 bytes lookup table */ + static const unsigned char ctz7_tab[128] = { + 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, + }; + U64 const mask = 0x0101010101010101ULL; + U64 const t = (((val >> 8) - mask) | val) & mask; + return ctz7_tab[(t * 0x0080402010080402ULL) >> 57]; +#else + /* this method doesn't consume memory space like the previous one, + * but it contains several branches, + * that may end up slowing execution */ + static const U32 by32 = sizeof(val)*4; /* 32 on 64 bits (goal), 16 on 32 bits. + Just to avoid some static analyzer complaining about shift by 32 on 32-bits target. + Note that this code path is never triggered in 32-bits mode. */ + unsigned r; + if (!(val>>by32)) { r=4; } else { r=0; val>>=by32; } + if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; } + r += (!val); + return r; +#endif +# endif + } else /* 32 bits */ { +# if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \ + ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (unsigned)__builtin_clz((U32)val) >> 3; +# else + val >>= 8; + val = ((((val + 0x00FFFF00) | 0x00FFFFFF) + val) | + (val + 0x00FF0000)) >> 24; + return (unsigned)val ^ 3; +# endif + } + } +} + + +#define STEPSIZE sizeof(reg_t) +LZ4_FORCE_INLINE +unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit) +{ + const BYTE* const pStart = pIn; + + if (likely(pIn < pInLimit-(STEPSIZE-1))) { + reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); + if (!diff) { + pIn+=STEPSIZE; pMatch+=STEPSIZE; + } else { + return LZ4_NbCommonBytes(diff); + } } + + while (likely(pIn < pInLimit-(STEPSIZE-1))) { + reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); + if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; } + pIn += LZ4_NbCommonBytes(diff); + return (unsigned)(pIn - pStart); + } + + if ((STEPSIZE==8) && (pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; } + if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; } + if ((pIn compression run slower on incompressible data */ + + +/*-************************************ +* Local Structures and types +**************************************/ +typedef enum { clearedTable = 0, byPtr, byU32, byU16 } tableType_t; + +/** + * This enum distinguishes several different modes of accessing previous + * content in the stream. + * + * - noDict : There is no preceding content. + * - withPrefix64k : Table entries up to ctx->dictSize before the current blob + * blob being compressed are valid and refer to the preceding + * content (of length ctx->dictSize), which is available + * contiguously preceding in memory the content currently + * being compressed. + * - usingExtDict : Like withPrefix64k, but the preceding content is somewhere + * else in memory, starting at ctx->dictionary with length + * ctx->dictSize. + * - usingDictCtx : Like usingExtDict, but everything concerning the preceding + * content is in a separate context, pointed to by + * ctx->dictCtx. ctx->dictionary, ctx->dictSize, and table + * entries in the current context that refer to positions + * preceding the beginning of the current compression are + * ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx + * ->dictSize describe the location and size of the preceding + * content, and matches are found by looking in the ctx + * ->dictCtx->hashTable. + */ +typedef enum { noDict = 0, withPrefix64k, usingExtDict, usingDictCtx } dict_directive; +typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive; + + +/*-************************************ +* Local Utils +**************************************/ +int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; } +const char* LZ4_versionString(void) { return LZ4_VERSION_STRING; } +int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); } +int LZ4_sizeofState(void) { return LZ4_STREAMSIZE; } + + +/*-************************************ +* Internal Definitions used in Tests +**************************************/ +#if defined (__cplusplus) +extern "C" { +#endif + +int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize); + +int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, + int compressedSize, int maxOutputSize, + const void* dictStart, size_t dictSize); + +#if defined (__cplusplus) +} +#endif + +/*-****************************** +* Compression functions +********************************/ +LZ4_FORCE_INLINE U32 LZ4_hash4(U32 sequence, tableType_t const tableType) +{ + if (tableType == byU16) + return ((sequence * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1))); + else + return ((sequence * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG)); +} + +LZ4_FORCE_INLINE U32 LZ4_hash5(U64 sequence, tableType_t const tableType) +{ + const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG; + if (LZ4_isLittleEndian()) { + const U64 prime5bytes = 889523592379ULL; + return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog)); + } else { + const U64 prime8bytes = 11400714785074694791ULL; + return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog)); + } +} + +LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void* const p, tableType_t const tableType) +{ + if ((sizeof(reg_t)==8) && (tableType != byU16)) return LZ4_hash5(LZ4_read_ARCH(p), tableType); + return LZ4_hash4(LZ4_read32(p), tableType); +} + +LZ4_FORCE_INLINE void LZ4_clearHash(U32 h, void* tableBase, tableType_t const tableType) +{ + switch (tableType) + { + default: /* fallthrough */ + case clearedTable: { /* illegal! */ assert(0); return; } + case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = NULL; return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = 0; return; } + case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = 0; return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putIndexOnHash(U32 idx, U32 h, void* tableBase, tableType_t const tableType) +{ + switch (tableType) + { + default: /* fallthrough */ + case clearedTable: /* fallthrough */ + case byPtr: { /* illegal! */ assert(0); return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = idx; return; } + case byU16: { U16* hashTable = (U16*) tableBase; assert(idx < 65536); hashTable[h] = (U16)idx; return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putPositionOnHash(const BYTE* p, U32 h, + void* tableBase, tableType_t const tableType, + const BYTE* srcBase) +{ + switch (tableType) + { + case clearedTable: { /* illegal! */ assert(0); return; } + case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; } + case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; } + } +} + +LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + U32 const h = LZ4_hashPosition(p, tableType); + LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase); +} + +/* LZ4_getIndexOnHash() : + * Index of match position registered in hash table. + * hash position must be calculated by using base+index, or dictBase+index. + * Assumption 1 : only valid if tableType == byU32 or byU16. + * Assumption 2 : h is presumed valid (within limits of hash table) + */ +LZ4_FORCE_INLINE U32 LZ4_getIndexOnHash(U32 h, const void* tableBase, tableType_t tableType) +{ + LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2); + if (tableType == byU32) { + const U32* const hashTable = (const U32*) tableBase; + assert(h < (1U << (LZ4_MEMORY_USAGE-2))); + return hashTable[h]; + } + if (tableType == byU16) { + const U16* const hashTable = (const U16*) tableBase; + assert(h < (1U << (LZ4_MEMORY_USAGE-1))); + return hashTable[h]; + } + assert(0); return 0; /* forbidden case */ +} + +static const BYTE* LZ4_getPositionOnHash(U32 h, const void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + if (tableType == byPtr) { const BYTE* const* hashTable = (const BYTE* const*) tableBase; return hashTable[h]; } + if (tableType == byU32) { const U32* const hashTable = (const U32*) tableBase; return hashTable[h] + srcBase; } + { const U16* const hashTable = (const U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */ +} + +LZ4_FORCE_INLINE const BYTE* +LZ4_getPosition(const BYTE* p, + const void* tableBase, tableType_t tableType, + const BYTE* srcBase) +{ + U32 const h = LZ4_hashPosition(p, tableType); + return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase); +} + +LZ4_FORCE_INLINE void +LZ4_prepareTable(LZ4_stream_t_internal* const cctx, + const int inputSize, + const tableType_t tableType) { + /* If the table hasn't been used, it's guaranteed to be zeroed out, and is + * therefore safe to use no matter what mode we're in. Otherwise, we figure + * out if it's safe to leave as is or whether it needs to be reset. + */ + if ((tableType_t)cctx->tableType != clearedTable) { + assert(inputSize >= 0); + if ((tableType_t)cctx->tableType != tableType + || ((tableType == byU16) && cctx->currentOffset + (unsigned)inputSize >= 0xFFFFU) + || ((tableType == byU32) && cctx->currentOffset > 1 GB) + || tableType == byPtr + || inputSize >= 4 KB) + { + DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx); + MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE); + cctx->currentOffset = 0; + cctx->tableType = (U32)clearedTable; + } else { + DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)"); + } + } + + /* Adding a gap, so all previous entries are > LZ4_DISTANCE_MAX back, is faster + * than compressing without a gap. However, compressing with + * currentOffset == 0 is faster still, so we preserve that case. + */ + if (cctx->currentOffset != 0 && tableType == byU32) { + DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset"); + cctx->currentOffset += 64 KB; + } + + /* Finally, clear history */ + cctx->dictCtx = NULL; + cctx->dictionary = NULL; + cctx->dictSize = 0; +} + +/** LZ4_compress_generic() : + * inlined, to ensure branches are decided at compilation time. + * Presumed already validated at this stage: + * - source != NULL + * - inputSize > 0 + */ +LZ4_FORCE_INLINE int LZ4_compress_generic_validated( + LZ4_stream_t_internal* const cctx, + const char* const source, + char* const dest, + const int inputSize, + int *inputConsumed, /* only written when outputDirective == fillOutput */ + const int maxOutputSize, + const limitedOutput_directive outputDirective, + const tableType_t tableType, + const dict_directive dictDirective, + const dictIssue_directive dictIssue, + const int acceleration) +{ + int result; + const BYTE* ip = (const BYTE*) source; + + U32 const startIndex = cctx->currentOffset; + const BYTE* base = (const BYTE*) source - startIndex; + const BYTE* lowLimit; + + const LZ4_stream_t_internal* dictCtx = (const LZ4_stream_t_internal*) cctx->dictCtx; + const BYTE* const dictionary = + dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary; + const U32 dictSize = + dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize; + const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */ + + int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx); + U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */ + const BYTE* const dictEnd = dictionary ? dictionary + dictSize : dictionary; + const BYTE* anchor = (const BYTE*) source; + const BYTE* const iend = ip + inputSize; + const BYTE* const mflimitPlusOne = iend - MFLIMIT + 1; + const BYTE* const matchlimit = iend - LASTLITERALS; + + /* the dictCtx currentOffset is indexed on the start of the dictionary, + * while a dictionary in the current context precedes the currentOffset */ + const BYTE* dictBase = !dictionary ? NULL : (dictDirective == usingDictCtx) ? + dictionary + dictSize - dictCtx->currentOffset : + dictionary + dictSize - startIndex; + + BYTE* op = (BYTE*) dest; + BYTE* const olimit = op + maxOutputSize; + + U32 offset = 0; + U32 forwardH; + + DEBUGLOG(5, "LZ4_compress_generic_validated: srcSize=%i, tableType=%u", inputSize, tableType); + assert(ip != NULL); + /* If init conditions are not met, we don't have to mark stream + * as having dirty context, since no action was taken yet */ + if (outputDirective == fillOutput && maxOutputSize < 1) { return 0; } /* Impossible to store anything */ + if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) { return 0; } /* Size too large (not within 64K limit) */ + if (tableType==byPtr) assert(dictDirective==noDict); /* only supported use case with byPtr */ + assert(acceleration >= 1); + + lowLimit = (const BYTE*)source - (dictDirective == withPrefix64k ? dictSize : 0); + + /* Update context state */ + if (dictDirective == usingDictCtx) { + /* Subsequent linked blocks can't use the dictionary. */ + /* Instead, they use the block we just compressed. */ + cctx->dictCtx = NULL; + cctx->dictSize = (U32)inputSize; + } else { + cctx->dictSize += (U32)inputSize; + } + cctx->currentOffset += (U32)inputSize; + cctx->tableType = (U32)tableType; + + if (inputSizehashTable, tableType, base); + ip++; forwardH = LZ4_hashPosition(ip, tableType); + + /* Main Loop */ + for ( ; ; ) { + const BYTE* match; + BYTE* token; + const BYTE* filledIp; + + /* Find a match */ + if (tableType == byPtr) { + const BYTE* forwardIp = ip; + int step = 1; + int searchMatchNb = acceleration << LZ4_skipTrigger; + do { + U32 const h = forwardH; + ip = forwardIp; + forwardIp += step; + step = (searchMatchNb++ >> LZ4_skipTrigger); + + if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; + assert(ip < mflimitPlusOne); + + match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base); + forwardH = LZ4_hashPosition(forwardIp, tableType); + LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base); + + } while ( (match+LZ4_DISTANCE_MAX < ip) + || (LZ4_read32(match) != LZ4_read32(ip)) ); + + } else { /* byU32, byU16 */ + + const BYTE* forwardIp = ip; + int step = 1; + int searchMatchNb = acceleration << LZ4_skipTrigger; + do { + U32 const h = forwardH; + U32 const current = (U32)(forwardIp - base); + U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); + assert(matchIndex <= current); + assert(forwardIp - base < (ptrdiff_t)(2 GB - 1)); + ip = forwardIp; + forwardIp += step; + step = (searchMatchNb++ >> LZ4_skipTrigger); + + if (unlikely(forwardIp > mflimitPlusOne)) goto _last_literals; + assert(ip < mflimitPlusOne); + + if (dictDirective == usingDictCtx) { + if (matchIndex < startIndex) { + /* there was no match, try the dictionary */ + assert(tableType == byU32); + matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); + match = dictBase + matchIndex; + matchIndex += dictDelta; /* make dictCtx index comparable with current context */ + lowLimit = dictionary; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; + } + } else if (dictDirective==usingExtDict) { + if (matchIndex < startIndex) { + DEBUGLOG(7, "extDict candidate: matchIndex=%5u < startIndex=%5u", matchIndex, startIndex); + assert(startIndex - matchIndex >= MINMATCH); + match = dictBase + matchIndex; + lowLimit = dictionary; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; + } + } else { /* single continuous memory segment */ + match = base + matchIndex; + } + forwardH = LZ4_hashPosition(forwardIp, tableType); + LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); + + DEBUGLOG(7, "candidate at pos=%u (offset=%u \n", matchIndex, current - matchIndex); + if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) { continue; } /* match outside of valid area */ + assert(matchIndex < current); + if ( ((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX)) + && (matchIndex+LZ4_DISTANCE_MAX < current)) { + continue; + } /* too far */ + assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */ + + if (LZ4_read32(match) == LZ4_read32(ip)) { + if (maybe_extMem) offset = current - matchIndex; + break; /* match found */ + } + + } while(1); + } + + /* Catch up */ + filledIp = ip; + while (((ip>anchor) & (match > lowLimit)) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; } + + /* Encode Literals */ + { unsigned const litLength = (unsigned)(ip - anchor); + token = op++; + if ((outputDirective == limitedOutput) && /* Check output buffer overflow */ + (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)) ) { + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + if ((outputDirective == fillOutput) && + (unlikely(op + (litLength+240)/255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))) { + op--; + goto _last_literals; + } + if (litLength >= RUN_MASK) { + int len = (int)(litLength - RUN_MASK); + *token = (RUN_MASK<= 255 ; len-=255) *op++ = 255; + *op++ = (BYTE)len; + } + else *token = (BYTE)(litLength< olimit)) { + /* the match was too close to the end, rewind and go to last literals */ + op = token; + goto _last_literals; + } + + /* Encode Offset */ + if (maybe_extMem) { /* static test */ + DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE*)source)); + assert(offset <= LZ4_DISTANCE_MAX && offset > 0); + LZ4_writeLE16(op, (U16)offset); op+=2; + } else { + DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match)); + assert(ip-match <= LZ4_DISTANCE_MAX); + LZ4_writeLE16(op, (U16)(ip - match)); op+=2; + } + + /* Encode MatchLength */ + { unsigned matchCode; + + if ( (dictDirective==usingExtDict || dictDirective==usingDictCtx) + && (lowLimit==dictionary) /* match within extDict */ ) { + const BYTE* limit = ip + (dictEnd-match); + assert(dictEnd > match); + if (limit > matchlimit) limit = matchlimit; + matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, limit); + ip += (size_t)matchCode + MINMATCH; + if (ip==limit) { + unsigned const more = LZ4_count(limit, (const BYTE*)source, matchlimit); + matchCode += more; + ip += more; + } + DEBUGLOG(6, " with matchLength=%u starting in extDict", matchCode+MINMATCH); + } else { + matchCode = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit); + ip += (size_t)matchCode + MINMATCH; + DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH); + } + + if ((outputDirective) && /* Check output buffer overflow */ + (unlikely(op + (1 + LASTLITERALS) + (matchCode+240)/255 > olimit)) ) { + if (outputDirective == fillOutput) { + /* Match description too long : reduce it */ + U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 1 - LASTLITERALS) * 255; + ip -= matchCode - newMatchCode; + assert(newMatchCode < matchCode); + matchCode = newMatchCode; + if (unlikely(ip <= filledIp)) { + /* We have already filled up to filledIp so if ip ends up less than filledIp + * we have positions in the hash table beyond the current position. This is + * a problem if we reuse the hash table. So we have to remove these positions + * from the hash table. + */ + const BYTE* ptr; + DEBUGLOG(5, "Clearing %u positions", (U32)(filledIp - ip)); + for (ptr = ip; ptr <= filledIp; ++ptr) { + U32 const h = LZ4_hashPosition(ptr, tableType); + LZ4_clearHash(h, cctx->hashTable, tableType); + } + } + } else { + assert(outputDirective == limitedOutput); + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + } + if (matchCode >= ML_MASK) { + *token += ML_MASK; + matchCode -= ML_MASK; + LZ4_write32(op, 0xFFFFFFFF); + while (matchCode >= 4*255) { + op+=4; + LZ4_write32(op, 0xFFFFFFFF); + matchCode -= 4*255; + } + op += matchCode / 255; + *op++ = (BYTE)(matchCode % 255); + } else + *token += (BYTE)(matchCode); + } + /* Ensure we have enough space for the last literals. */ + assert(!(outputDirective == fillOutput && op + 1 + LASTLITERALS > olimit)); + + anchor = ip; + + /* Test end of chunk */ + if (ip >= mflimitPlusOne) break; + + /* Fill table */ + LZ4_putPosition(ip-2, cctx->hashTable, tableType, base); + + /* Test next position */ + if (tableType == byPtr) { + + match = LZ4_getPosition(ip, cctx->hashTable, tableType, base); + LZ4_putPosition(ip, cctx->hashTable, tableType, base); + if ( (match+LZ4_DISTANCE_MAX >= ip) + && (LZ4_read32(match) == LZ4_read32(ip)) ) + { token=op++; *token=0; goto _next_match; } + + } else { /* byU32, byU16 */ + + U32 const h = LZ4_hashPosition(ip, tableType); + U32 const current = (U32)(ip-base); + U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType); + assert(matchIndex < current); + if (dictDirective == usingDictCtx) { + if (matchIndex < startIndex) { + /* there was no match, try the dictionary */ + matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32); + match = dictBase + matchIndex; + lowLimit = dictionary; /* required for match length counter */ + matchIndex += dictDelta; + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; /* required for match length counter */ + } + } else if (dictDirective==usingExtDict) { + if (matchIndex < startIndex) { + match = dictBase + matchIndex; + lowLimit = dictionary; /* required for match length counter */ + } else { + match = base + matchIndex; + lowLimit = (const BYTE*)source; /* required for match length counter */ + } + } else { /* single memory segment */ + match = base + matchIndex; + } + LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType); + assert(matchIndex < current); + if ( ((dictIssue==dictSmall) ? (matchIndex >= prefixIdxLimit) : 1) + && (((tableType==byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex+LZ4_DISTANCE_MAX >= current)) + && (LZ4_read32(match) == LZ4_read32(ip)) ) { + token=op++; + *token=0; + if (maybe_extMem) offset = current - matchIndex; + DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i", + (int)(anchor-(const BYTE*)source), 0, (int)(ip-(const BYTE*)source)); + goto _next_match; + } + } + + /* Prepare next loop */ + forwardH = LZ4_hashPosition(++ip, tableType); + + } + +_last_literals: + /* Encode Last Literals */ + { size_t lastRun = (size_t)(iend - anchor); + if ( (outputDirective) && /* Check output buffer overflow */ + (op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) { + if (outputDirective == fillOutput) { + /* adapt lastRun to fill 'dst' */ + assert(olimit >= op); + lastRun = (size_t)(olimit-op) - 1/*token*/; + lastRun -= (lastRun + 256 - RUN_MASK) / 256; /*additional length tokens*/ + } else { + assert(outputDirective == limitedOutput); + return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */ + } + } + DEBUGLOG(6, "Final literal run : %i literals", (int)lastRun); + if (lastRun >= RUN_MASK) { + size_t accumulator = lastRun - RUN_MASK; + *op++ = RUN_MASK << ML_BITS; + for(; accumulator >= 255 ; accumulator-=255) *op++ = 255; + *op++ = (BYTE) accumulator; + } else { + *op++ = (BYTE)(lastRun< 0); + DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, result); + return result; +} + +/** LZ4_compress_generic() : + * inlined, to ensure branches are decided at compilation time; + * takes care of src == (NULL, 0) + * and forward the rest to LZ4_compress_generic_validated */ +LZ4_FORCE_INLINE int LZ4_compress_generic( + LZ4_stream_t_internal* const cctx, + const char* const src, + char* const dst, + const int srcSize, + int *inputConsumed, /* only written when outputDirective == fillOutput */ + const int dstCapacity, + const limitedOutput_directive outputDirective, + const tableType_t tableType, + const dict_directive dictDirective, + const dictIssue_directive dictIssue, + const int acceleration) +{ + DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, dstCapacity=%i", + srcSize, dstCapacity); + + if ((U32)srcSize > (U32)LZ4_MAX_INPUT_SIZE) { return 0; } /* Unsupported srcSize, too large (or negative) */ + if (srcSize == 0) { /* src == NULL supported if srcSize == 0 */ + if (outputDirective != notLimited && dstCapacity <= 0) return 0; /* no output, can't write anything */ + DEBUGLOG(5, "Generating an empty block"); + assert(outputDirective == notLimited || dstCapacity >= 1); + assert(dst != NULL); + dst[0] = 0; + if (outputDirective == fillOutput) { + assert (inputConsumed != NULL); + *inputConsumed = 0; + } + return 1; + } + assert(src != NULL); + + return LZ4_compress_generic_validated(cctx, src, dst, srcSize, + inputConsumed, /* only written into if outputDirective == fillOutput */ + dstCapacity, outputDirective, + tableType, dictDirective, dictIssue, acceleration); +} + + +int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) +{ + LZ4_stream_t_internal* const ctx = & LZ4_initStream(state, sizeof(LZ4_stream_t)) -> internal_donotuse; + assert(ctx != NULL); + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + if (maxOutputSize >= LZ4_compressBound(inputSize)) { + if (inputSize < LZ4_64Klimit) { + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration); + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + if (inputSize < LZ4_64Klimit) { + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration); + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } +} + +/** + * LZ4_compress_fast_extState_fastReset() : + * A variant of LZ4_compress_fast_extState(). + * + * Using this variant avoids an expensive initialization step. It is only safe + * to call if the state buffer is known to be correctly initialized already + * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of + * "correctly initialized"). + */ +int LZ4_compress_fast_extState_fastReset(void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration) +{ + LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse; + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + + if (dstCapacity >= LZ4_compressBound(srcSize)) { + if (srcSize < LZ4_64Klimit) { + const tableType_t tableType = byU16; + LZ4_prepareTable(ctx, srcSize, tableType); + if (ctx->currentOffset) { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration); + } else { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + LZ4_prepareTable(ctx, srcSize, tableType); + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration); + } + } else { + if (srcSize < LZ4_64Klimit) { + const tableType_t tableType = byU16; + LZ4_prepareTable(ctx, srcSize, tableType); + if (ctx->currentOffset) { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration); + } else { + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } else { + const tableType_t tableType = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + LZ4_prepareTable(ctx, srcSize, tableType); + return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration); + } + } +} + + +int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) +{ + int result; +#if (LZ4_HEAPMODE) + LZ4_stream_t* ctxPtr = ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ + if (ctxPtr == NULL) return 0; +#else + LZ4_stream_t ctx; + LZ4_stream_t* const ctxPtr = &ctx; +#endif + result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration); + +#if (LZ4_HEAPMODE) + FREEMEM(ctxPtr); +#endif + return result; +} + + +int LZ4_compress_default(const char* src, char* dst, int srcSize, int maxOutputSize) +{ + return LZ4_compress_fast(src, dst, srcSize, maxOutputSize, 1); +} + + +/* Note!: This function leaves the stream in an unclean/broken state! + * It is not safe to subsequently use the same state with a _fastReset() or + * _continue() call without resetting it. */ +static int LZ4_compress_destSize_extState (LZ4_stream_t* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize) +{ + void* const s = LZ4_initStream(state, sizeof (*state)); + assert(s != NULL); (void)s; + + if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) { /* compression success is guaranteed */ + return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1); + } else { + if (*srcSizePtr < LZ4_64Klimit) { + return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1); + } else { + tableType_t const addrMode = ((sizeof(void*)==4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32; + return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, addrMode, noDict, noDictIssue, 1); + } } +} + + +int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize) +{ +#if (LZ4_HEAPMODE) + LZ4_stream_t* ctx = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ + if (ctx == NULL) return 0; +#else + LZ4_stream_t ctxBody; + LZ4_stream_t* ctx = &ctxBody; +#endif + + int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize); + +#if (LZ4_HEAPMODE) + FREEMEM(ctx); +#endif + return result; +} + + + +/*-****************************** +* Streaming functions +********************************/ + +LZ4_stream_t* LZ4_createStream(void) +{ + LZ4_stream_t* const lz4s = (LZ4_stream_t*)ALLOC(sizeof(LZ4_stream_t)); + LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */ + DEBUGLOG(4, "LZ4_createStream %p", lz4s); + if (lz4s == NULL) return NULL; + LZ4_initStream(lz4s, sizeof(*lz4s)); + return lz4s; +} + +static size_t LZ4_stream_t_alignment(void) +{ +#if LZ4_ALIGN_TEST + typedef struct { char c; LZ4_stream_t t; } t_a; + return sizeof(t_a) - sizeof(LZ4_stream_t); +#else + return 1; /* effectively disabled */ +#endif +} + +LZ4_stream_t* LZ4_initStream (void* buffer, size_t size) +{ + DEBUGLOG(5, "LZ4_initStream"); + if (buffer == NULL) { return NULL; } + if (size < sizeof(LZ4_stream_t)) { return NULL; } + if (!LZ4_isAligned(buffer, LZ4_stream_t_alignment())) return NULL; + MEM_INIT(buffer, 0, sizeof(LZ4_stream_t_internal)); + return (LZ4_stream_t*)buffer; +} + +/* resetStream is now deprecated, + * prefer initStream() which is more general */ +void LZ4_resetStream (LZ4_stream_t* LZ4_stream) +{ + DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream); + MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t_internal)); +} + +void LZ4_resetStream_fast(LZ4_stream_t* ctx) { + LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32); +} + +int LZ4_freeStream (LZ4_stream_t* LZ4_stream) +{ + if (!LZ4_stream) return 0; /* support free on NULL */ + DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream); + FREEMEM(LZ4_stream); + return (0); +} + + +#define HASH_UNIT sizeof(reg_t) +int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize) +{ + LZ4_stream_t_internal* dict = &LZ4_dict->internal_donotuse; + const tableType_t tableType = byU32; + const BYTE* p = (const BYTE*)dictionary; + const BYTE* const dictEnd = p + dictSize; + const BYTE* base; + + DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict); + + /* It's necessary to reset the context, + * and not just continue it with prepareTable() + * to avoid any risk of generating overflowing matchIndex + * when compressing using this dictionary */ + LZ4_resetStream(LZ4_dict); + + /* We always increment the offset by 64 KB, since, if the dict is longer, + * we truncate it to the last 64k, and if it's shorter, we still want to + * advance by a whole window length so we can provide the guarantee that + * there are only valid offsets in the window, which allows an optimization + * in LZ4_compress_fast_continue() where it uses noDictIssue even when the + * dictionary isn't a full 64k. */ + dict->currentOffset += 64 KB; + + if (dictSize < (int)HASH_UNIT) { + return 0; + } + + if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB; + base = dictEnd - dict->currentOffset; + dict->dictionary = p; + dict->dictSize = (U32)(dictEnd - p); + dict->tableType = (U32)tableType; + + while (p <= dictEnd-HASH_UNIT) { + LZ4_putPosition(p, dict->hashTable, tableType, base); + p+=3; + } + + return (int)dict->dictSize; +} + +void LZ4_attach_dictionary(LZ4_stream_t* workingStream, const LZ4_stream_t* dictionaryStream) { + const LZ4_stream_t_internal* dictCtx = dictionaryStream == NULL ? NULL : + &(dictionaryStream->internal_donotuse); + + DEBUGLOG(4, "LZ4_attach_dictionary (%p, %p, size %u)", + workingStream, dictionaryStream, + dictCtx != NULL ? dictCtx->dictSize : 0); + + if (dictCtx != NULL) { + /* If the current offset is zero, we will never look in the + * external dictionary context, since there is no value a table + * entry can take that indicate a miss. In that case, we need + * to bump the offset to something non-zero. + */ + if (workingStream->internal_donotuse.currentOffset == 0) { + workingStream->internal_donotuse.currentOffset = 64 KB; + } + + /* Don't actually attach an empty dictionary. + */ + if (dictCtx->dictSize == 0) { + dictCtx = NULL; + } + } + workingStream->internal_donotuse.dictCtx = dictCtx; +} + + +static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, int nextSize) +{ + assert(nextSize >= 0); + if (LZ4_dict->currentOffset + (unsigned)nextSize > 0x80000000) { /* potential ptrdiff_t overflow (32-bits mode) */ + /* rescale hash table */ + U32 const delta = LZ4_dict->currentOffset - 64 KB; + const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize; + int i; + DEBUGLOG(4, "LZ4_renormDictT"); + for (i=0; ihashTable[i] < delta) LZ4_dict->hashTable[i]=0; + else LZ4_dict->hashTable[i] -= delta; + } + LZ4_dict->currentOffset = 64 KB; + if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB; + LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize; + } +} + + +int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, + const char* source, char* dest, + int inputSize, int maxOutputSize, + int acceleration) +{ + const tableType_t tableType = byU32; + LZ4_stream_t_internal* streamPtr = &LZ4_stream->internal_donotuse; + const BYTE* dictEnd = streamPtr->dictionary + streamPtr->dictSize; + + DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i)", inputSize); + + LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */ + if (acceleration < 1) acceleration = LZ4_ACCELERATION_DEFAULT; + if (acceleration > LZ4_ACCELERATION_MAX) acceleration = LZ4_ACCELERATION_MAX; + + /* invalidate tiny dictionaries */ + if ( (streamPtr->dictSize-1 < 4-1) /* intentional underflow */ + && (dictEnd != (const BYTE*)source) ) { + DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary); + streamPtr->dictSize = 0; + streamPtr->dictionary = (const BYTE*)source; + dictEnd = (const BYTE*)source; + } + + /* Check overlapping input/dictionary space */ + { const BYTE* sourceEnd = (const BYTE*) source + inputSize; + if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) { + streamPtr->dictSize = (U32)(dictEnd - sourceEnd); + if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB; + if (streamPtr->dictSize < 4) streamPtr->dictSize = 0; + streamPtr->dictionary = dictEnd - streamPtr->dictSize; + } + } + + /* prefix mode : source data follows dictionary */ + if (dictEnd == (const BYTE*)source) { + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) + return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration); + else + return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration); + } + + /* external dictionary mode */ + { int result; + if (streamPtr->dictCtx) { + /* We depend here on the fact that dictCtx'es (produced by + * LZ4_loadDict) guarantee that their tables contain no references + * to offsets between dictCtx->currentOffset - 64 KB and + * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe + * to use noDictIssue even when the dict isn't a full 64 KB. + */ + if (inputSize > 4 KB) { + /* For compressing large blobs, it is faster to pay the setup + * cost to copy the dictionary's tables into the active context, + * so that the compression loop is only looking into one table. + */ + LZ4_memcpy(streamPtr, streamPtr->dictCtx, sizeof(*streamPtr)); + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration); + } + } else { + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration); + } + } + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)inputSize; + return result; + } +} + + +/* Hidden debug function, to force-test external dictionary mode */ +int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int srcSize) +{ + LZ4_stream_t_internal* streamPtr = &LZ4_dict->internal_donotuse; + int result; + + LZ4_renormDictT(streamPtr, srcSize); + + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) { + result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1); + } else { + result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1); + } + + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)srcSize; + + return result; +} + + +/*! LZ4_saveDict() : + * If previously compressed data block is not guaranteed to remain available at its memory location, + * save it into a safer place (char* safeBuffer). + * Note : you don't need to call LZ4_loadDict() afterwards, + * dictionary is immediately usable, you can therefore call LZ4_compress_fast_continue(). + * Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. + */ +int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize) +{ + LZ4_stream_t_internal* const dict = &LZ4_dict->internal_donotuse; + const BYTE* const previousDictEnd = dict->dictionary + dict->dictSize; + + if ((U32)dictSize > 64 KB) { dictSize = 64 KB; } /* useless to define a dictionary > 64 KB */ + if ((U32)dictSize > dict->dictSize) { dictSize = (int)dict->dictSize; } + + if (safeBuffer == NULL) assert(dictSize == 0); + if (dictSize > 0) + memmove(safeBuffer, previousDictEnd - dictSize, dictSize); + + dict->dictionary = (const BYTE*)safeBuffer; + dict->dictSize = (U32)dictSize; + + return dictSize; +} + + + +/*-******************************* + * Decompression functions + ********************************/ + +typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive; +typedef enum { decode_full_block = 0, partial_decode = 1 } earlyEnd_directive; + +#undef MIN +#define MIN(a,b) ( (a) < (b) ? (a) : (b) ) + +/* Read the variable-length literal or match length. + * + * ip - pointer to use as input. + * lencheck - end ip. Return an error if ip advances >= lencheck. + * loop_check - check ip >= lencheck in body of loop. Returns loop_error if so. + * initial_check - check ip >= lencheck before start of loop. Returns initial_error if so. + * error (output) - error code. Should be set to 0 before call. + */ +typedef enum { loop_error = -2, initial_error = -1, ok = 0 } variable_length_error; +LZ4_FORCE_INLINE unsigned +read_variable_length(const BYTE**ip, const BYTE* lencheck, + int loop_check, int initial_check, + variable_length_error* error) +{ + U32 length = 0; + U32 s; + if (initial_check && unlikely((*ip) >= lencheck)) { /* overflow detection */ + *error = initial_error; + return length; + } + do { + s = **ip; + (*ip)++; + length += s; + if (loop_check && unlikely((*ip) >= lencheck)) { /* overflow detection */ + *error = loop_error; + return length; + } + } while (s==255); + + return length; +} + +/*! LZ4_decompress_generic() : + * This generic decompression function covers all use cases. + * It shall be instantiated several times, using different sets of directives. + * Note that it is important for performance that this function really get inlined, + * in order to remove useless branches during compilation optimization. + */ +LZ4_FORCE_INLINE int +LZ4_decompress_generic( + const char* const src, + char* const dst, + int srcSize, + int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */ + + endCondition_directive endOnInput, /* endOnOutputSize, endOnInputSize */ + earlyEnd_directive partialDecoding, /* full, partial */ + dict_directive dict, /* noDict, withPrefix64k, usingExtDict */ + const BYTE* const lowPrefix, /* always <= dst, == dst when no prefix */ + const BYTE* const dictStart, /* only if dict==usingExtDict */ + const size_t dictSize /* note : = 0 if noDict */ + ) +{ + if (src == NULL) { return -1; } + + { const BYTE* ip = (const BYTE*) src; + const BYTE* const iend = ip + srcSize; + + BYTE* op = (BYTE*) dst; + BYTE* const oend = op + outputSize; + BYTE* cpy; + + const BYTE* const dictEnd = (dictStart == NULL) ? NULL : dictStart + dictSize; + + const int safeDecode = (endOnInput==endOnInputSize); + const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB))); + + + /* Set up the "end" pointers for the shortcut. */ + const BYTE* const shortiend = iend - (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/; + const BYTE* const shortoend = oend - (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/; + + const BYTE* match; + size_t offset; + unsigned token; + size_t length; + + + DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize); + + /* Special cases */ + assert(lowPrefix <= op); + if ((endOnInput) && (unlikely(outputSize==0))) { + /* Empty output buffer */ + if (partialDecoding) return 0; + return ((srcSize==1) && (*ip==0)) ? 0 : -1; + } + if ((!endOnInput) && (unlikely(outputSize==0))) { return (*ip==0 ? 1 : -1); } + if ((endOnInput) && unlikely(srcSize==0)) { return -1; } + + /* Currently the fast loop shows a regression on qualcomm arm chips. */ +#if LZ4_FAST_DEC_LOOP + if ((oend - op) < FASTLOOP_SAFE_DISTANCE) { + DEBUGLOG(6, "skip fast decode loop"); + goto safe_decode; + } + + /* Fast loop : decode sequences as long as output < iend-FASTLOOP_SAFE_DISTANCE */ + while (1) { + /* Main fastloop assertion: We can always wildcopy FASTLOOP_SAFE_DISTANCE */ + assert(oend - op >= FASTLOOP_SAFE_DISTANCE); + if (endOnInput) { assert(ip < iend); } + token = *ip++; + length = token >> ML_BITS; /* literal length */ + + assert(!endOnInput || ip <= iend); /* ip < iend before the increment */ + + /* decode literal length */ + if (length == RUN_MASK) { + variable_length_error error = ok; + length += read_variable_length(&ip, iend-RUN_MASK, (int)endOnInput, (int)endOnInput, &error); + if (error == initial_error) { goto _output_error; } + if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ + if ((safeDecode) && unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ + + /* copy literals */ + cpy = op+length; + LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); + if (endOnInput) { /* LZ4_decompress_safe() */ + if ((cpy>oend-32) || (ip+length>iend-32)) { goto safe_literal_copy; } + LZ4_wildCopy32(op, ip, cpy); + } else { /* LZ4_decompress_fast() */ + if (cpy>oend-8) { goto safe_literal_copy; } + LZ4_wildCopy8(op, ip, cpy); /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time : + * it doesn't know input length, and only relies on end-of-block properties */ + } + ip += length; op = cpy; + } else { + cpy = op+length; + if (endOnInput) { /* LZ4_decompress_safe() */ + DEBUGLOG(7, "copy %u bytes in a 16-bytes stripe", (unsigned)length); + /* We don't need to check oend, since we check it once for each loop below */ + if (ip > iend-(16 + 1/*max lit + offset + nextToken*/)) { goto safe_literal_copy; } + /* Literals can only be 14, but hope compilers optimize if we copy by a register size */ + LZ4_memcpy(op, ip, 16); + } else { /* LZ4_decompress_fast() */ + /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time : + * it doesn't know input length, and relies on end-of-block properties */ + LZ4_memcpy(op, ip, 8); + if (length > 8) { LZ4_memcpy(op+8, ip+8, 8); } + } + ip += length; op = cpy; + } + + /* get offset */ + offset = LZ4_readLE16(ip); ip+=2; + match = op - offset; + assert(match <= op); + + /* get matchlength */ + length = token & ML_MASK; + + if (length == ML_MASK) { + variable_length_error error = ok; + if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ + length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error); + if (error != ok) { goto _output_error; } + if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) { goto _output_error; } /* overflow detection */ + length += MINMATCH; + if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { + goto safe_match_copy; + } + } else { + length += MINMATCH; + if (op + length >= oend - FASTLOOP_SAFE_DISTANCE) { + goto safe_match_copy; + } + + /* Fastpath check: Avoids a branch in LZ4_wildCopy32 if true */ + if ((dict == withPrefix64k) || (match >= lowPrefix)) { + if (offset >= 8) { + assert(match >= lowPrefix); + assert(match <= op); + assert(op + 18 <= oend); + + LZ4_memcpy(op, match, 8); + LZ4_memcpy(op+8, match+8, 8); + LZ4_memcpy(op+16, match+16, 2); + op += length; + continue; + } } } + + if (checkOffset && (unlikely(match + dictSize < lowPrefix))) { goto _output_error; } /* Error : offset outside buffers */ + /* match starting within external dictionary */ + if ((dict==usingExtDict) && (match < lowPrefix)) { + if (unlikely(op+length > oend-LASTLITERALS)) { + if (partialDecoding) { + DEBUGLOG(7, "partialDecoding: dictionary match, close to dstEnd"); + length = MIN(length, (size_t)(oend-op)); + } else { + goto _output_error; /* end-of-block condition violated */ + } } + + if (length <= (size_t)(lowPrefix-match)) { + /* match fits entirely within external dictionary : just copy */ + memmove(op, dictEnd - (lowPrefix-match), length); + op += length; + } else { + /* match stretches into both external dictionary and current block */ + size_t const copySize = (size_t)(lowPrefix - match); + size_t const restSize = length - copySize; + LZ4_memcpy(op, dictEnd - copySize, copySize); + op += copySize; + if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ + BYTE* const endOfMatch = op + restSize; + const BYTE* copyFrom = lowPrefix; + while (op < endOfMatch) { *op++ = *copyFrom++; } + } else { + LZ4_memcpy(op, lowPrefix, restSize); + op += restSize; + } } + continue; + } + + /* copy match within block */ + cpy = op + length; + + assert((op <= oend) && (oend-op >= 32)); + if (unlikely(offset<16)) { + LZ4_memcpy_using_offset(op, match, cpy, offset); + } else { + LZ4_wildCopy32(op, match, cpy); + } + + op = cpy; /* wildcopy correction */ + } + safe_decode: +#endif + + /* Main Loop : decode remaining sequences where output < FASTLOOP_SAFE_DISTANCE */ + while (1) { + token = *ip++; + length = token >> ML_BITS; /* literal length */ + + assert(!endOnInput || ip <= iend); /* ip < iend before the increment */ + + /* A two-stage shortcut for the most common case: + * 1) If the literal length is 0..14, and there is enough space, + * enter the shortcut and copy 16 bytes on behalf of the literals + * (in the fast mode, only 8 bytes can be safely copied this way). + * 2) Further if the match length is 4..18, copy 18 bytes in a similar + * manner; but we ensure that there's enough space in the output for + * those 18 bytes earlier, upon entering the shortcut (in other words, + * there is a combined check for both stages). + */ + if ( (endOnInput ? length != RUN_MASK : length <= 8) + /* strictly "less than" on input, to re-enter the loop with at least one byte */ + && likely((endOnInput ? ip < shortiend : 1) & (op <= shortoend)) ) { + /* Copy the literals */ + LZ4_memcpy(op, ip, endOnInput ? 16 : 8); + op += length; ip += length; + + /* The second stage: prepare for match copying, decode full info. + * If it doesn't work out, the info won't be wasted. */ + length = token & ML_MASK; /* match length */ + offset = LZ4_readLE16(ip); ip += 2; + match = op - offset; + assert(match <= op); /* check overflow */ + + /* Do not deal with overlapping matches. */ + if ( (length != ML_MASK) + && (offset >= 8) + && (dict==withPrefix64k || match >= lowPrefix) ) { + /* Copy the match. */ + LZ4_memcpy(op + 0, match + 0, 8); + LZ4_memcpy(op + 8, match + 8, 8); + LZ4_memcpy(op +16, match +16, 2); + op += length + MINMATCH; + /* Both stages worked, load the next token. */ + continue; + } + + /* The second stage didn't work out, but the info is ready. + * Propel it right to the point of match copying. */ + goto _copy_match; + } + + /* decode literal length */ + if (length == RUN_MASK) { + variable_length_error error = ok; + length += read_variable_length(&ip, iend-RUN_MASK, (int)endOnInput, (int)endOnInput, &error); + if (error == initial_error) { goto _output_error; } + if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)(op))) { goto _output_error; } /* overflow detection */ + if ((safeDecode) && unlikely((uptrval)(ip)+length<(uptrval)(ip))) { goto _output_error; } /* overflow detection */ + } + + /* copy literals */ + cpy = op+length; +#if LZ4_FAST_DEC_LOOP + safe_literal_copy: +#endif + LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH); + if ( ((endOnInput) && ((cpy>oend-MFLIMIT) || (ip+length>iend-(2+1+LASTLITERALS))) ) + || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH)) ) + { + /* We've either hit the input parsing restriction or the output parsing restriction. + * In the normal scenario, decoding a full block, it must be the last sequence, + * otherwise it's an error (invalid input or dimensions). + * In partialDecoding scenario, it's necessary to ensure there is no buffer overflow. + */ + if (partialDecoding) { + /* Since we are partial decoding we may be in this block because of the output parsing + * restriction, which is not valid since the output buffer is allowed to be undersized. + */ + assert(endOnInput); + DEBUGLOG(7, "partialDecoding: copying literals, close to input or output end") + DEBUGLOG(7, "partialDecoding: literal length = %u", (unsigned)length); + DEBUGLOG(7, "partialDecoding: remaining space in dstBuffer : %i", (int)(oend - op)); + DEBUGLOG(7, "partialDecoding: remaining space in srcBuffer : %i", (int)(iend - ip)); + /* Finishing in the middle of a literals segment, + * due to lack of input. + */ + if (ip+length > iend) { + length = (size_t)(iend-ip); + cpy = op + length; + } + /* Finishing in the middle of a literals segment, + * due to lack of output space. + */ + if (cpy > oend) { + cpy = oend; + assert(op<=oend); + length = (size_t)(oend-op); + } + } else { + /* We must be on the last sequence because of the parsing limitations so check + * that we exactly regenerate the original size (must be exact when !endOnInput). + */ + if ((!endOnInput) && (cpy != oend)) { goto _output_error; } + /* We must be on the last sequence (or invalid) because of the parsing limitations + * so check that we exactly consume the input and don't overrun the output buffer. + */ + if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) { + DEBUGLOG(6, "should have been last run of literals") + DEBUGLOG(6, "ip(%p) + length(%i) = %p != iend (%p)", ip, (int)length, ip+length, iend); + DEBUGLOG(6, "or cpy(%p) > oend(%p)", cpy, oend); + goto _output_error; + } + } + memmove(op, ip, length); /* supports overlapping memory regions; only matters for in-place decompression scenarios */ + ip += length; + op += length; + /* Necessarily EOF when !partialDecoding. + * When partialDecoding, it is EOF if we've either + * filled the output buffer or + * can't proceed with reading an offset for following match. + */ + if (!partialDecoding || (cpy == oend) || (ip >= (iend-2))) { + break; + } + } else { + LZ4_wildCopy8(op, ip, cpy); /* may overwrite up to WILDCOPYLENGTH beyond cpy */ + ip += length; op = cpy; + } + + /* get offset */ + offset = LZ4_readLE16(ip); ip+=2; + match = op - offset; + + /* get matchlength */ + length = token & ML_MASK; + + _copy_match: + if (length == ML_MASK) { + variable_length_error error = ok; + length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error); + if (error != ok) goto _output_error; + if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) goto _output_error; /* overflow detection */ + } + length += MINMATCH; + +#if LZ4_FAST_DEC_LOOP + safe_match_copy: +#endif + if ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) goto _output_error; /* Error : offset outside buffers */ + /* match starting within external dictionary */ + if ((dict==usingExtDict) && (match < lowPrefix)) { + if (unlikely(op+length > oend-LASTLITERALS)) { + if (partialDecoding) length = MIN(length, (size_t)(oend-op)); + else goto _output_error; /* doesn't respect parsing restriction */ + } + + if (length <= (size_t)(lowPrefix-match)) { + /* match fits entirely within external dictionary : just copy */ + memmove(op, dictEnd - (lowPrefix-match), length); + op += length; + } else { + /* match stretches into both external dictionary and current block */ + size_t const copySize = (size_t)(lowPrefix - match); + size_t const restSize = length - copySize; + LZ4_memcpy(op, dictEnd - copySize, copySize); + op += copySize; + if (restSize > (size_t)(op - lowPrefix)) { /* overlap copy */ + BYTE* const endOfMatch = op + restSize; + const BYTE* copyFrom = lowPrefix; + while (op < endOfMatch) *op++ = *copyFrom++; + } else { + LZ4_memcpy(op, lowPrefix, restSize); + op += restSize; + } } + continue; + } + assert(match >= lowPrefix); + + /* copy match within block */ + cpy = op + length; + + /* partialDecoding : may end anywhere within the block */ + assert(op<=oend); + if (partialDecoding && (cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { + size_t const mlen = MIN(length, (size_t)(oend-op)); + const BYTE* const matchEnd = match + mlen; + BYTE* const copyEnd = op + mlen; + if (matchEnd > op) { /* overlap copy */ + while (op < copyEnd) { *op++ = *match++; } + } else { + LZ4_memcpy(op, match, mlen); + } + op = copyEnd; + if (op == oend) { break; } + continue; + } + + if (unlikely(offset<8)) { + LZ4_write32(op, 0); /* silence msan warning when offset==0 */ + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += inc32table[offset]; + LZ4_memcpy(op+4, match, 4); + match -= dec64table[offset]; + } else { + LZ4_memcpy(op, match, 8); + match += 8; + } + op += 8; + + if (unlikely(cpy > oend-MATCH_SAFEGUARD_DISTANCE)) { + BYTE* const oCopyLimit = oend - (WILDCOPYLENGTH-1); + if (cpy > oend-LASTLITERALS) { goto _output_error; } /* Error : last LASTLITERALS bytes must be literals (uncompressed) */ + if (op < oCopyLimit) { + LZ4_wildCopy8(op, match, oCopyLimit); + match += oCopyLimit - op; + op = oCopyLimit; + } + while (op < cpy) { *op++ = *match++; } + } else { + LZ4_memcpy(op, match, 8); + if (length > 16) { LZ4_wildCopy8(op+8, match+8, cpy); } + } + op = cpy; /* wildcopy correction */ + } + + /* end of decoding */ + if (endOnInput) { + DEBUGLOG(5, "decoded %i bytes", (int) (((char*)op)-dst)); + return (int) (((char*)op)-dst); /* Nb of output bytes decoded */ + } else { + return (int) (((const char*)ip)-src); /* Nb of input bytes read */ + } + + /* Overflow error detected */ + _output_error: + return (int) (-(((const char*)ip)-src))-1; + } +} + + +/*===== Instantiate the API decoding functions. =====*/ + +LZ4_FORCE_O2 +int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, + endOnInputSize, decode_full_block, noDict, + (BYTE*)dest, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_safe_partial(const char* src, char* dst, int compressedSize, int targetOutputSize, int dstCapacity) +{ + dstCapacity = MIN(targetOutputSize, dstCapacity); + return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity, + endOnInputSize, partial_decode, + noDict, (BYTE*)dst, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_fast(const char* source, char* dest, int originalSize) +{ + return LZ4_decompress_generic(source, dest, 0, originalSize, + endOnOutputSize, decode_full_block, withPrefix64k, + (BYTE*)dest - 64 KB, NULL, 0); +} + +/*===== Instantiate a few more decoding cases, used more than once. =====*/ + +LZ4_FORCE_O2 /* Exported, an obsolete API function. */ +int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + endOnInputSize, decode_full_block, withPrefix64k, + (BYTE*)dest - 64 KB, NULL, 0); +} + +/* Another obsolete API function, paired with the previous one. */ +int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize) +{ + /* LZ4_decompress_fast doesn't validate match offsets, + * and thus serves well with any prefixed dictionary. */ + return LZ4_decompress_fast(source, dest, originalSize); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_safe_withSmallPrefix(const char* source, char* dest, int compressedSize, int maxOutputSize, + size_t prefixSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + endOnInputSize, decode_full_block, noDict, + (BYTE*)dest-prefixSize, NULL, 0); +} + +LZ4_FORCE_O2 +int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, + int compressedSize, int maxOutputSize, + const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + endOnInputSize, decode_full_block, usingExtDict, + (BYTE*)dest, (const BYTE*)dictStart, dictSize); +} + +LZ4_FORCE_O2 +static int LZ4_decompress_fast_extDict(const char* source, char* dest, int originalSize, + const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, 0, originalSize, + endOnOutputSize, decode_full_block, usingExtDict, + (BYTE*)dest, (const BYTE*)dictStart, dictSize); +} + +/* The "double dictionary" mode, for use with e.g. ring buffers: the first part + * of the dictionary is passed as prefix, and the second via dictStart + dictSize. + * These routines are used only once, in LZ4_decompress_*_continue(). + */ +LZ4_FORCE_INLINE +int LZ4_decompress_safe_doubleDict(const char* source, char* dest, int compressedSize, int maxOutputSize, + size_t prefixSize, const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, + endOnInputSize, decode_full_block, usingExtDict, + (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize); +} + +LZ4_FORCE_INLINE +int LZ4_decompress_fast_doubleDict(const char* source, char* dest, int originalSize, + size_t prefixSize, const void* dictStart, size_t dictSize) +{ + return LZ4_decompress_generic(source, dest, 0, originalSize, + endOnOutputSize, decode_full_block, usingExtDict, + (BYTE*)dest-prefixSize, (const BYTE*)dictStart, dictSize); +} + +/*===== streaming decompression functions =====*/ + +LZ4_streamDecode_t* LZ4_createStreamDecode(void) +{ + LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t)); + LZ4_STATIC_ASSERT(LZ4_STREAMDECODESIZE >= sizeof(LZ4_streamDecode_t_internal)); /* A compilation error here means LZ4_STREAMDECODESIZE is not large enough */ + return lz4s; +} + +int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream) +{ + if (LZ4_stream == NULL) { return 0; } /* support free on NULL */ + FREEMEM(LZ4_stream); + return 0; +} + +/*! LZ4_setStreamDecode() : + * Use this function to instruct where to find the dictionary. + * This function is not necessary if previous data is still available where it was decoded. + * Loading a size of 0 is allowed (same effect as no dictionary). + * @return : 1 if OK, 0 if error + */ +int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize) +{ + LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; + lz4sd->prefixSize = (size_t) dictSize; + lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize; + lz4sd->externalDict = NULL; + lz4sd->extDictSize = 0; + return 1; +} + +/*! LZ4_decoderRingBufferSize() : + * when setting a ring buffer for streaming decompression (optional scenario), + * provides the minimum size of this ring buffer + * to be compatible with any source respecting maxBlockSize condition. + * Note : in a ring buffer scenario, + * blocks are presumed decompressed next to each other. + * When not enough space remains for next block (remainingSize < maxBlockSize), + * decoding resumes from beginning of ring buffer. + * @return : minimum ring buffer size, + * or 0 if there is an error (invalid maxBlockSize). + */ +int LZ4_decoderRingBufferSize(int maxBlockSize) +{ + if (maxBlockSize < 0) return 0; + if (maxBlockSize > LZ4_MAX_INPUT_SIZE) return 0; + if (maxBlockSize < 16) maxBlockSize = 16; + return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize); +} + +/* +*_continue() : + These decoding functions allow decompression of multiple blocks in "streaming" mode. + Previously decoded blocks must still be available at the memory position where they were decoded. + If it's not possible, save the relevant part of decoded data into a safe buffer, + and indicate where it stands using LZ4_setStreamDecode() +*/ +LZ4_FORCE_O2 +int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; + int result; + + if (lz4sd->prefixSize == 0) { + /* The first call, no dictionary yet. */ + assert(lz4sd->extDictSize == 0); + result = LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)result; + lz4sd->prefixEnd = (BYTE*)dest + result; + } else if (lz4sd->prefixEnd == (BYTE*)dest) { + /* They're rolling the current segment. */ + if (lz4sd->prefixSize >= 64 KB - 1) + result = LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); + else if (lz4sd->extDictSize == 0) + result = LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, + lz4sd->prefixSize); + else + result = LZ4_decompress_safe_doubleDict(source, dest, compressedSize, maxOutputSize, + lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize += (size_t)result; + lz4sd->prefixEnd += result; + } else { + /* The buffer wraps around, or they're switching to another buffer. */ + lz4sd->extDictSize = lz4sd->prefixSize; + lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; + result = LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, + lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)result; + lz4sd->prefixEnd = (BYTE*)dest + result; + } + + return result; +} + +LZ4_FORCE_O2 +int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize) +{ + LZ4_streamDecode_t_internal* lz4sd = &LZ4_streamDecode->internal_donotuse; + int result; + assert(originalSize >= 0); + + if (lz4sd->prefixSize == 0) { + assert(lz4sd->extDictSize == 0); + result = LZ4_decompress_fast(source, dest, originalSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)originalSize; + lz4sd->prefixEnd = (BYTE*)dest + originalSize; + } else if (lz4sd->prefixEnd == (BYTE*)dest) { + if (lz4sd->prefixSize >= 64 KB - 1 || lz4sd->extDictSize == 0) + result = LZ4_decompress_fast(source, dest, originalSize); + else + result = LZ4_decompress_fast_doubleDict(source, dest, originalSize, + lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize += (size_t)originalSize; + lz4sd->prefixEnd += originalSize; + } else { + lz4sd->extDictSize = lz4sd->prefixSize; + lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; + result = LZ4_decompress_fast_extDict(source, dest, originalSize, + lz4sd->externalDict, lz4sd->extDictSize); + if (result <= 0) return result; + lz4sd->prefixSize = (size_t)originalSize; + lz4sd->prefixEnd = (BYTE*)dest + originalSize; + } + + return result; +} + + +/* +Advanced decoding functions : +*_usingDict() : + These decoding functions work the same as "_continue" ones, + the dictionary must be explicitly provided within parameters +*/ + +int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) +{ + if (dictSize==0) + return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize); + if (dictStart+dictSize == dest) { + if (dictSize >= 64 KB - 1) { + return LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, (size_t)dictSize); + } + assert(dictSize >= 0); + return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, (size_t)dictSize); +} + +int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize) +{ + if (dictSize==0 || dictStart+dictSize == dest) + return LZ4_decompress_fast(source, dest, originalSize); + assert(dictSize >= 0); + return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, (size_t)dictSize); +} + + +/*=************************************************* +* Obsolete Functions +***************************************************/ +/* obsolete compression functions */ +int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) +{ + return LZ4_compress_default(source, dest, inputSize, maxOutputSize); +} +int LZ4_compress(const char* src, char* dest, int srcSize) +{ + return LZ4_compress_default(src, dest, srcSize, LZ4_compressBound(srcSize)); +} +int LZ4_compress_limitedOutput_withState (void* state, const char* src, char* dst, int srcSize, int dstSize) +{ + return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1); +} +int LZ4_compress_withState (void* state, const char* src, char* dst, int srcSize) +{ + return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1); +} +int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int dstCapacity) +{ + return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1); +} +int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize) +{ + return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1); +} + +/* +These decompression functions are deprecated and should no longer be used. +They are only provided here for compatibility with older user programs. +- LZ4_uncompress is totally equivalent to LZ4_decompress_fast +- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe +*/ +int LZ4_uncompress (const char* source, char* dest, int outputSize) +{ + return LZ4_decompress_fast(source, dest, outputSize); +} +int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) +{ + return LZ4_decompress_safe(source, dest, isize, maxOutputSize); +} + +/* Obsolete Streaming functions */ + +int LZ4_sizeofStreamState(void) { return LZ4_STREAMSIZE; } + +int LZ4_resetStreamState(void* state, char* inputBuffer) +{ + (void)inputBuffer; + LZ4_resetStream((LZ4_stream_t*)state); + return 0; +} + +void* LZ4_create (char* inputBuffer) +{ + (void)inputBuffer; + return LZ4_createStream(); +} + +char* LZ4_slideInputBuffer (void* state) +{ + /* avoid const char * -> char * conversion warning */ + return (char *)(uptrval)((LZ4_stream_t*)state)->internal_donotuse.dictionary; +} + +#endif /* LZ4_COMMONDEFS_ONLY */ diff --git a/cbits/lz4.h b/cbits/lz4.h new file mode 100644 --- /dev/null +++ b/cbits/lz4.h @@ -0,0 +1,774 @@ +/* + * LZ4 - Fast LZ compression algorithm + * Header File + * Copyright (C) 2011-present, Yann Collet. + + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * 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. + + You can contact the author at : + - LZ4 homepage : http://www.lz4.org + - LZ4 source repository : https://github.com/lz4/lz4 +*/ +#if defined (__cplusplus) +extern "C" { +#endif + +#ifndef LZ4_H_2983827168210 +#define LZ4_H_2983827168210 + +/* --- Dependency --- */ +#include /* size_t */ + + +/** + Introduction + + LZ4 is lossless compression algorithm, providing compression speed >500 MB/s per core, + scalable with multi-cores CPU. It features an extremely fast decoder, with speed in + multiple GB/s per core, typically reaching RAM speed limits on multi-core systems. + + The LZ4 compression library provides in-memory compression and decompression functions. + It gives full buffer control to user. + Compression can be done in: + - a single step (described as Simple Functions) + - a single step, reusing a context (described in Advanced Functions) + - unbounded multiple steps (described as Streaming compression) + + lz4.h generates and decodes LZ4-compressed blocks (doc/lz4_Block_format.md). + Decompressing such a compressed block requires additional metadata. + Exact metadata depends on exact decompression function. + For the typical case of LZ4_decompress_safe(), + metadata includes block's compressed size, and maximum bound of decompressed size. + Each application is free to encode and pass such metadata in whichever way it wants. + + lz4.h only handle blocks, it can not generate Frames. + + Blocks are different from Frames (doc/lz4_Frame_format.md). + Frames bundle both blocks and metadata in a specified manner. + Embedding metadata is required for compressed data to be self-contained and portable. + Frame format is delivered through a companion API, declared in lz4frame.h. + The `lz4` CLI can only manage frames. +*/ + +/*^*************************************************************** +* Export parameters +*****************************************************************/ +/* +* LZ4_DLL_EXPORT : +* Enable exporting of functions when building a Windows DLL +* LZ4LIB_VISIBILITY : +* Control library symbols visibility. +*/ +#ifndef LZ4LIB_VISIBILITY +# if defined(__GNUC__) && (__GNUC__ >= 4) +# define LZ4LIB_VISIBILITY __attribute__ ((visibility ("default"))) +# else +# define LZ4LIB_VISIBILITY +# endif +#endif +#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1) +# define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY +#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1) +# define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ +#else +# define LZ4LIB_API LZ4LIB_VISIBILITY +#endif + +/*------ Version ------*/ +#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */ +#define LZ4_VERSION_MINOR 9 /* for new (non-breaking) interface capabilities */ +#define LZ4_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */ + +#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE) + +#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE +#define LZ4_QUOTE(str) #str +#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str) +#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) + +LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version */ +LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version */ + + +/*-************************************ +* Tuning parameter +**************************************/ +/*! + * LZ4_MEMORY_USAGE : + * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) + * Increasing memory usage improves compression ratio. + * Reduced memory usage may improve speed, thanks to better cache locality. + * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache + */ +#ifndef LZ4_MEMORY_USAGE +# define LZ4_MEMORY_USAGE 14 +#endif + + +/*-************************************ +* Simple Functions +**************************************/ +/*! LZ4_compress_default() : + * Compresses 'srcSize' bytes from buffer 'src' + * into already allocated 'dst' buffer of size 'dstCapacity'. + * Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize). + * It also runs faster, so it's a recommended setting. + * If the function cannot compress 'src' into a more limited 'dst' budget, + * compression stops *immediately*, and the function result is zero. + * In which case, 'dst' content is undefined (invalid). + * srcSize : max supported value is LZ4_MAX_INPUT_SIZE. + * dstCapacity : size of buffer 'dst' (which must be already allocated) + * @return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity) + * or 0 if compression fails + * Note : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer). + */ +LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity); + +/*! LZ4_decompress_safe() : + * compressedSize : is the exact complete size of the compressed block. + * dstCapacity : is the size of destination buffer (which must be already allocated), presumed an upper bound of decompressed size. + * @return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity) + * If destination buffer is not large enough, decoding will stop and output an error code (negative value). + * If the source stream is detected malformed, the function will stop decoding and return a negative result. + * Note 1 : This function is protected against malicious data packets : + * it will never writes outside 'dst' buffer, nor read outside 'source' buffer, + * even if the compressed block is maliciously modified to order the decoder to do these actions. + * In such case, the decoder stops immediately, and considers the compressed block malformed. + * Note 2 : compressedSize and dstCapacity must be provided to the function, the compressed block does not contain them. + * The implementation is free to send / store / derive this information in whichever way is most beneficial. + * If there is a need for a different format which bundles together both compressed data and its metadata, consider looking at lz4frame.h instead. + */ +LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity); + + +/*-************************************ +* Advanced Functions +**************************************/ +#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */ +#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16) + +/*! LZ4_compressBound() : + Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible) + This function is primarily useful for memory allocation purposes (destination buffer size). + Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example). + Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize) + inputSize : max supported value is LZ4_MAX_INPUT_SIZE + return : maximum output size in a "worst case" scenario + or 0, if input size is incorrect (too large or negative) +*/ +LZ4LIB_API int LZ4_compressBound(int inputSize); + +/*! LZ4_compress_fast() : + Same as LZ4_compress_default(), but allows selection of "acceleration" factor. + The larger the acceleration value, the faster the algorithm, but also the lesser the compression. + It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed. + An acceleration value of "1" is the same as regular LZ4_compress_default() + Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT (currently == 1, see lz4.c). + Values > LZ4_ACCELERATION_MAX will be replaced by LZ4_ACCELERATION_MAX (currently == 65537, see lz4.c). +*/ +LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); + + +/*! LZ4_compress_fast_extState() : + * Same as LZ4_compress_fast(), using an externally allocated memory space for its state. + * Use LZ4_sizeofState() to know how much memory must be allocated, + * and allocate it on 8-bytes boundaries (using `malloc()` typically). + * Then, provide this buffer as `void* state` to compression function. + */ +LZ4LIB_API int LZ4_sizeofState(void); +LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); + + +/*! LZ4_compress_destSize() : + * Reverse the logic : compresses as much data as possible from 'src' buffer + * into already allocated buffer 'dst', of size >= 'targetDestSize'. + * This function either compresses the entire 'src' content into 'dst' if it's large enough, + * or fill 'dst' buffer completely with as much data as possible from 'src'. + * note: acceleration parameter is fixed to "default". + * + * *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'. + * New value is necessarily <= input value. + * @return : Nb bytes written into 'dst' (necessarily <= targetDestSize) + * or 0 if compression fails. + * + * Note : from v1.8.2 to v1.9.1, this function had a bug (fixed un v1.9.2+): + * the produced compressed content could, in specific circumstances, + * require to be decompressed into a destination buffer larger + * by at least 1 byte than the content to decompress. + * If an application uses `LZ4_compress_destSize()`, + * it's highly recommended to update liblz4 to v1.9.2 or better. + * If this can't be done or ensured, + * the receiving decompression function should provide + * a dstCapacity which is > decompressedSize, by at least 1 byte. + * See https://github.com/lz4/lz4/issues/859 for details + */ +LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize); + + +/*! LZ4_decompress_safe_partial() : + * Decompress an LZ4 compressed block, of size 'srcSize' at position 'src', + * into destination buffer 'dst' of size 'dstCapacity'. + * Up to 'targetOutputSize' bytes will be decoded. + * The function stops decoding on reaching this objective. + * This can be useful to boost performance + * whenever only the beginning of a block is required. + * + * @return : the number of bytes decoded in `dst` (necessarily <= targetOutputSize) + * If source stream is detected malformed, function returns a negative result. + * + * Note 1 : @return can be < targetOutputSize, if compressed block contains less data. + * + * Note 2 : targetOutputSize must be <= dstCapacity + * + * Note 3 : this function effectively stops decoding on reaching targetOutputSize, + * so dstCapacity is kind of redundant. + * This is because in older versions of this function, + * decoding operation would still write complete sequences. + * Therefore, there was no guarantee that it would stop writing at exactly targetOutputSize, + * it could write more bytes, though only up to dstCapacity. + * Some "margin" used to be required for this operation to work properly. + * Thankfully, this is no longer necessary. + * The function nonetheless keeps the same signature, in an effort to preserve API compatibility. + * + * Note 4 : If srcSize is the exact size of the block, + * then targetOutputSize can be any value, + * including larger than the block's decompressed size. + * The function will, at most, generate block's decompressed size. + * + * Note 5 : If srcSize is _larger_ than block's compressed size, + * then targetOutputSize **MUST** be <= block's decompressed size. + * Otherwise, *silent corruption will occur*. + */ +LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity); + + +/*-********************************************* +* Streaming Compression Functions +***********************************************/ +typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */ + +LZ4LIB_API LZ4_stream_t* LZ4_createStream(void); +LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr); + +/*! LZ4_resetStream_fast() : v1.9.0+ + * Use this to prepare an LZ4_stream_t for a new chain of dependent blocks + * (e.g., LZ4_compress_fast_continue()). + * + * An LZ4_stream_t must be initialized once before usage. + * This is automatically done when created by LZ4_createStream(). + * However, should the LZ4_stream_t be simply declared on stack (for example), + * it's necessary to initialize it first, using LZ4_initStream(). + * + * After init, start any new stream with LZ4_resetStream_fast(). + * A same LZ4_stream_t can be re-used multiple times consecutively + * and compress multiple streams, + * provided that it starts each new stream with LZ4_resetStream_fast(). + * + * LZ4_resetStream_fast() is much faster than LZ4_initStream(), + * but is not compatible with memory regions containing garbage data. + * + * Note: it's only useful to call LZ4_resetStream_fast() + * in the context of streaming compression. + * The *extState* functions perform their own resets. + * Invoking LZ4_resetStream_fast() before is redundant, and even counterproductive. + */ +LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr); + +/*! LZ4_loadDict() : + * Use this function to reference a static dictionary into LZ4_stream_t. + * The dictionary must remain available during compression. + * LZ4_loadDict() triggers a reset, so any previous data will be forgotten. + * The same dictionary will have to be loaded on decompression side for successful decoding. + * Dictionary are useful for better compression of small data (KB range). + * While LZ4 accept any input as dictionary, + * results are generally better when using Zstandard's Dictionary Builder. + * Loading a size of 0 is allowed, and is the same as reset. + * @return : loaded dictionary size, in bytes (necessarily <= 64 KB) + */ +LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize); + +/*! LZ4_compress_fast_continue() : + * Compress 'src' content using data from previously compressed blocks, for better compression ratio. + * 'dst' buffer must be already allocated. + * If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster. + * + * @return : size of compressed block + * or 0 if there is an error (typically, cannot fit into 'dst'). + * + * Note 1 : Each invocation to LZ4_compress_fast_continue() generates a new block. + * Each block has precise boundaries. + * Each block must be decompressed separately, calling LZ4_decompress_*() with relevant metadata. + * It's not possible to append blocks together and expect a single invocation of LZ4_decompress_*() to decompress them together. + * + * Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory ! + * + * Note 3 : When input is structured as a double-buffer, each buffer can have any size, including < 64 KB. + * Make sure that buffers are separated, by at least one byte. + * This construction ensures that each block only depends on previous block. + * + * Note 4 : If input buffer is a ring-buffer, it can have any size, including < 64 KB. + * + * Note 5 : After an error, the stream status is undefined (invalid), it can only be reset or freed. + */ +LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); + +/*! LZ4_saveDict() : + * If last 64KB data cannot be guaranteed to remain available at its current memory location, + * save it into a safer place (char* safeBuffer). + * This is schematically equivalent to a memcpy() followed by LZ4_loadDict(), + * but is much faster, because LZ4_saveDict() doesn't need to rebuild tables. + * @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error. + */ +LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize); + + +/*-********************************************** +* Streaming Decompression Functions +* Bufferless synchronous API +************************************************/ +typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */ + +/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() : + * creation / destruction of streaming decompression tracking context. + * A tracking context can be re-used multiple times. + */ +LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void); +LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream); + +/*! LZ4_setStreamDecode() : + * An LZ4_streamDecode_t context can be allocated once and re-used multiple times. + * Use this function to start decompression of a new stream of blocks. + * A dictionary can optionally be set. Use NULL or size 0 for a reset order. + * Dictionary is presumed stable : it must remain accessible and unmodified during next decompression. + * @return : 1 if OK, 0 if error + */ +LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize); + +/*! LZ4_decoderRingBufferSize() : v1.8.2+ + * Note : in a ring buffer scenario (optional), + * blocks are presumed decompressed next to each other + * up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize), + * at which stage it resumes from beginning of ring buffer. + * When setting such a ring buffer for streaming decompression, + * provides the minimum size of this ring buffer + * to be compatible with any source respecting maxBlockSize condition. + * @return : minimum ring buffer size, + * or 0 if there is an error (invalid maxBlockSize). + */ +LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize); +#define LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize) (65536 + 14 + (maxBlockSize)) /* for static allocation; maxBlockSize presumed valid */ + +/*! LZ4_decompress_*_continue() : + * These decoding functions allow decompression of consecutive blocks in "streaming" mode. + * A block is an unsplittable entity, it must be presented entirely to a decompression function. + * Decompression functions only accepts one block at a time. + * The last 64KB of previously decoded data *must* remain available and unmodified at the memory position where they were decoded. + * If less than 64KB of data has been decoded, all the data must be present. + * + * Special : if decompression side sets a ring buffer, it must respect one of the following conditions : + * - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize). + * maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes. + * In which case, encoding and decoding buffers do not need to be synchronized. + * Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize. + * - Synchronized mode : + * Decompression buffer size is _exactly_ the same as compression buffer size, + * and follows exactly same update rule (block boundaries at same positions), + * and decoding function is provided with exact decompressed size of each block (exception for last block of the stream), + * _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB). + * - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes. + * In which case, encoding and decoding buffers do not need to be synchronized, + * and encoding ring buffer can have any size, including small ones ( < 64 KB). + * + * Whenever these conditions are not possible, + * save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression, + * then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block. +*/ +LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity); + + +/*! LZ4_decompress_*_usingDict() : + * These decoding functions work the same as + * a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue() + * They are stand-alone, and don't need an LZ4_streamDecode_t structure. + * Dictionary is presumed stable : it must remain accessible and unmodified during decompression. + * Performance tip : Decompression speed can be substantially increased + * when dst == dictStart + dictSize. + */ +LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize); + +#endif /* LZ4_H_2983827168210 */ + + +/*^************************************* + * !!!!!! STATIC LINKING ONLY !!!!!! + ***************************************/ + +/*-**************************************************************************** + * Experimental section + * + * Symbols declared in this section must be considered unstable. Their + * signatures or semantics may change, or they may be removed altogether in the + * future. They are therefore only safe to depend on when the caller is + * statically linked against the library. + * + * To protect against unsafe usage, not only are the declarations guarded, + * the definitions are hidden by default + * when building LZ4 as a shared/dynamic library. + * + * In order to access these declarations, + * define LZ4_STATIC_LINKING_ONLY in your application + * before including LZ4's headers. + * + * In order to make their implementations accessible dynamically, you must + * define LZ4_PUBLISH_STATIC_FUNCTIONS when building the LZ4 library. + ******************************************************************************/ + +#ifdef LZ4_STATIC_LINKING_ONLY + +#ifndef LZ4_STATIC_3504398509 +#define LZ4_STATIC_3504398509 + +#ifdef LZ4_PUBLISH_STATIC_FUNCTIONS +#define LZ4LIB_STATIC_API LZ4LIB_API +#else +#define LZ4LIB_STATIC_API +#endif + + +/*! LZ4_compress_fast_extState_fastReset() : + * A variant of LZ4_compress_fast_extState(). + * + * Using this variant avoids an expensive initialization step. + * It is only safe to call if the state buffer is known to be correctly initialized already + * (see above comment on LZ4_resetStream_fast() for a definition of "correctly initialized"). + * From a high level, the difference is that + * this function initializes the provided state with a call to something like LZ4_resetStream_fast() + * while LZ4_compress_fast_extState() starts with a call to LZ4_resetStream(). + */ +LZ4LIB_STATIC_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); + +/*! LZ4_attach_dictionary() : + * This is an experimental API that allows + * efficient use of a static dictionary many times. + * + * Rather than re-loading the dictionary buffer into a working context before + * each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a + * working LZ4_stream_t, this function introduces a no-copy setup mechanism, + * in which the working stream references the dictionary stream in-place. + * + * Several assumptions are made about the state of the dictionary stream. + * Currently, only streams which have been prepared by LZ4_loadDict() should + * be expected to work. + * + * Alternatively, the provided dictionaryStream may be NULL, + * in which case any existing dictionary stream is unset. + * + * If a dictionary is provided, it replaces any pre-existing stream history. + * The dictionary contents are the only history that can be referenced and + * logically immediately precede the data compressed in the first subsequent + * compression call. + * + * The dictionary will only remain attached to the working stream through the + * first compression call, at the end of which it is cleared. The dictionary + * stream (and source buffer) must remain in-place / accessible / unchanged + * through the completion of the first compression call on the stream. + */ +LZ4LIB_STATIC_API void LZ4_attach_dictionary(LZ4_stream_t* workingStream, const LZ4_stream_t* dictionaryStream); + + +/*! In-place compression and decompression + * + * It's possible to have input and output sharing the same buffer, + * for highly contrained memory environments. + * In both cases, it requires input to lay at the end of the buffer, + * and decompression to start at beginning of the buffer. + * Buffer size must feature some margin, hence be larger than final size. + * + * |<------------------------buffer--------------------------------->| + * |<-----------compressed data--------->| + * |<-----------decompressed size------------------>| + * |<----margin---->| + * + * This technique is more useful for decompression, + * since decompressed size is typically larger, + * and margin is short. + * + * In-place decompression will work inside any buffer + * which size is >= LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize). + * This presumes that decompressedSize > compressedSize. + * Otherwise, it means compression actually expanded data, + * and it would be more efficient to store such data with a flag indicating it's not compressed. + * This can happen when data is not compressible (already compressed, or encrypted). + * + * For in-place compression, margin is larger, as it must be able to cope with both + * history preservation, requiring input data to remain unmodified up to LZ4_DISTANCE_MAX, + * and data expansion, which can happen when input is not compressible. + * As a consequence, buffer size requirements are much higher, + * and memory savings offered by in-place compression are more limited. + * + * There are ways to limit this cost for compression : + * - Reduce history size, by modifying LZ4_DISTANCE_MAX. + * Note that it is a compile-time constant, so all compressions will apply this limit. + * Lower values will reduce compression ratio, except when input_size < LZ4_DISTANCE_MAX, + * so it's a reasonable trick when inputs are known to be small. + * - Require the compressor to deliver a "maximum compressed size". + * This is the `dstCapacity` parameter in `LZ4_compress*()`. + * When this size is < LZ4_COMPRESSBOUND(inputSize), then compression can fail, + * in which case, the return code will be 0 (zero). + * The caller must be ready for these cases to happen, + * and typically design a backup scheme to send data uncompressed. + * The combination of both techniques can significantly reduce + * the amount of margin required for in-place compression. + * + * In-place compression can work in any buffer + * which size is >= (maxCompressedSize) + * with maxCompressedSize == LZ4_COMPRESSBOUND(srcSize) for guaranteed compression success. + * LZ4_COMPRESS_INPLACE_BUFFER_SIZE() depends on both maxCompressedSize and LZ4_DISTANCE_MAX, + * so it's possible to reduce memory requirements by playing with them. + */ + +#define LZ4_DECOMPRESS_INPLACE_MARGIN(compressedSize) (((compressedSize) >> 8) + 32) +#define LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize) ((decompressedSize) + LZ4_DECOMPRESS_INPLACE_MARGIN(decompressedSize)) /**< note: presumes that compressedSize < decompressedSize. note2: margin is overestimated a bit, since it could use compressedSize instead */ + +#ifndef LZ4_DISTANCE_MAX /* history window size; can be user-defined at compile time */ +# define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */ +#endif + +#define LZ4_COMPRESS_INPLACE_MARGIN (LZ4_DISTANCE_MAX + 32) /* LZ4_DISTANCE_MAX can be safely replaced by srcSize when it's smaller */ +#define LZ4_COMPRESS_INPLACE_BUFFER_SIZE(maxCompressedSize) ((maxCompressedSize) + LZ4_COMPRESS_INPLACE_MARGIN) /**< maxCompressedSize is generally LZ4_COMPRESSBOUND(inputSize), but can be set to any lower value, with the risk that compression can fail (return code 0(zero)) */ + +#endif /* LZ4_STATIC_3504398509 */ +#endif /* LZ4_STATIC_LINKING_ONLY */ + + + +#ifndef LZ4_H_98237428734687 +#define LZ4_H_98237428734687 + +/*-************************************************************ + * Private Definitions + ************************************************************** + * Do not use these definitions directly. + * They are only exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`. + * Accessing members will expose user code to API and/or ABI break in future versions of the library. + **************************************************************/ +#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2) +#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE) +#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */ + +#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) +# include + typedef int8_t LZ4_i8; + typedef uint8_t LZ4_byte; + typedef uint16_t LZ4_u16; + typedef uint32_t LZ4_u32; +#else + typedef signed char LZ4_i8; + typedef unsigned char LZ4_byte; + typedef unsigned short LZ4_u16; + typedef unsigned int LZ4_u32; +#endif + +typedef struct LZ4_stream_t_internal LZ4_stream_t_internal; +struct LZ4_stream_t_internal { + LZ4_u32 hashTable[LZ4_HASH_SIZE_U32]; + LZ4_u32 currentOffset; + LZ4_u32 tableType; + const LZ4_byte* dictionary; + const LZ4_stream_t_internal* dictCtx; + LZ4_u32 dictSize; +}; + +typedef struct { + const LZ4_byte* externalDict; + size_t extDictSize; + const LZ4_byte* prefixEnd; + size_t prefixSize; +} LZ4_streamDecode_t_internal; + + +/*! LZ4_stream_t : + * Do not use below internal definitions directly ! + * Declare or allocate an LZ4_stream_t instead. + * LZ4_stream_t can also be created using LZ4_createStream(), which is recommended. + * The structure definition can be convenient for static allocation + * (on stack, or as part of larger structure). + * Init this structure with LZ4_initStream() before first use. + * note : only use this definition in association with static linking ! + * this definition is not API/ABI safe, and may change in future versions. + */ +#define LZ4_STREAMSIZE 16416 /* static size, for inter-version compatibility */ +#define LZ4_STREAMSIZE_VOIDP (LZ4_STREAMSIZE / sizeof(void*)) +union LZ4_stream_u { + void* table[LZ4_STREAMSIZE_VOIDP]; + LZ4_stream_t_internal internal_donotuse; +}; /* previously typedef'd to LZ4_stream_t */ + + +/*! LZ4_initStream() : v1.9.0+ + * An LZ4_stream_t structure must be initialized at least once. + * This is automatically done when invoking LZ4_createStream(), + * but it's not when the structure is simply declared on stack (for example). + * + * Use LZ4_initStream() to properly initialize a newly declared LZ4_stream_t. + * It can also initialize any arbitrary buffer of sufficient size, + * and will @return a pointer of proper type upon initialization. + * + * Note : initialization fails if size and alignment conditions are not respected. + * In which case, the function will @return NULL. + * Note2: An LZ4_stream_t structure guarantees correct alignment and size. + * Note3: Before v1.9.0, use LZ4_resetStream() instead + */ +LZ4LIB_API LZ4_stream_t* LZ4_initStream (void* buffer, size_t size); + + +/*! LZ4_streamDecode_t : + * information structure to track an LZ4 stream during decompression. + * init this structure using LZ4_setStreamDecode() before first use. + * note : only use in association with static linking ! + * this definition is not API/ABI safe, + * and may change in a future version ! + */ +#define LZ4_STREAMDECODESIZE_U64 (4 + ((sizeof(void*)==16) ? 2 : 0) /*AS-400*/ ) +#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long)) +union LZ4_streamDecode_u { + unsigned long long table[LZ4_STREAMDECODESIZE_U64]; + LZ4_streamDecode_t_internal internal_donotuse; +} ; /* previously typedef'd to LZ4_streamDecode_t */ + + + +/*-************************************ +* Obsolete Functions +**************************************/ + +/*! Deprecation warnings + * + * Deprecated functions make the compiler generate a warning when invoked. + * This is meant to invite users to update their source code. + * Should deprecation warnings be a problem, it is generally possible to disable them, + * typically with -Wno-deprecated-declarations for gcc + * or _CRT_SECURE_NO_WARNINGS in Visual. + * + * Another method is to define LZ4_DISABLE_DEPRECATE_WARNINGS + * before including the header file. + */ +#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS +# define LZ4_DEPRECATED(message) /* disable deprecation warnings */ +#else +# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */ +# define LZ4_DEPRECATED(message) [[deprecated(message)]] +# elif defined(_MSC_VER) +# define LZ4_DEPRECATED(message) __declspec(deprecated(message)) +# elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 45)) +# define LZ4_DEPRECATED(message) __attribute__((deprecated(message))) +# elif defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 31) +# define LZ4_DEPRECATED(message) __attribute__((deprecated)) +# else +# pragma message("WARNING: LZ4_DEPRECATED needs custom implementation for this compiler") +# define LZ4_DEPRECATED(message) /* disabled */ +# endif +#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */ + +/*! Obsolete compression functions (since v1.7.3) */ +LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* src, char* dest, int srcSize); +LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* src, char* dest, int srcSize, int maxOutputSize); +LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize); +LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize); +LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize); +LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize); + +/*! Obsolete decompression functions (since v1.8.0) */ +LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize); +LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize); + +/* Obsolete streaming functions (since v1.7.0) + * degraded functionality; do not use! + * + * In order to perform streaming compression, these functions depended on data + * that is no longer tracked in the state. They have been preserved as well as + * possible: using them will still produce a correct output. However, they don't + * actually retain any history between compression calls. The compression ratio + * achieved will therefore be no better than compressing each chunk + * independently. + */ +LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer); +LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int LZ4_sizeofStreamState(void); +LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API int LZ4_resetStreamState(void* state, char* inputBuffer); +LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API char* LZ4_slideInputBuffer (void* state); + +/*! Obsolete streaming decoding functions (since v1.7.0) */ +LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize); +LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize); + +/*! Obsolete LZ4_decompress_fast variants (since v1.9.0) : + * These functions used to be faster than LZ4_decompress_safe(), + * but this is no longer the case. They are now slower. + * This is because LZ4_decompress_fast() doesn't know the input size, + * and therefore must progress more cautiously into the input buffer to not read beyond the end of block. + * On top of that `LZ4_decompress_fast()` is not protected vs malformed or malicious inputs, making it a security liability. + * As a consequence, LZ4_decompress_fast() is strongly discouraged, and deprecated. + * + * The last remaining LZ4_decompress_fast() specificity is that + * it can decompress a block without knowing its compressed size. + * Such functionality can be achieved in a more secure manner + * by employing LZ4_decompress_safe_partial(). + * + * Parameters: + * originalSize : is the uncompressed size to regenerate. + * `dst` must be already allocated, its size must be >= 'originalSize' bytes. + * @return : number of bytes read from source buffer (== compressed size). + * The function expects to finish at block's end exactly. + * If the source stream is detected malformed, the function stops decoding and returns a negative result. + * note : LZ4_decompress_fast*() requires originalSize. Thanks to this information, it never writes past the output buffer. + * However, since it doesn't know its 'src' size, it may read an unknown amount of input, past input buffer bounds. + * Also, since match offsets are not validated, match reads from 'src' may underflow too. + * These issues never happen if input (compressed) data is correct. + * But they may happen if input data is invalid (error or intentional tampering). + * As a consequence, use these functions in trusted environments with trusted data **only**. + */ +LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe() instead") +LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize); +LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_continue() instead") +LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize); +LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_usingDict() instead") +LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize); + +/*! LZ4_resetStream() : + * An LZ4_stream_t structure must be initialized at least once. + * This is done with LZ4_initStream(), or LZ4_resetStream(). + * Consider switching to LZ4_initStream(), + * invoking LZ4_resetStream() will trigger deprecation warnings in the future. + */ +LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr); + + +#endif /* LZ4_H_98237428734687 */ + + +#if defined (__cplusplus) +} +#endif diff --git a/download-corpora.sh b/download-corpora.sh new file mode 100644 --- /dev/null +++ b/download-corpora.sh @@ -0,0 +1,49 @@ +#!/bin/sh + +# This script downloads the corpora required to run certain tests and +# benchmarks. + +BASE_DIR="corpora" +CORPORA="cantrbry artificl large" + +# $1 = list of files to download from http://corpus.canterbury.ac.nz/resources/ +# without suffix +# $2 = directory to download and unzip (relative) +download_and_unzip() { + # Make the base directory if it does not exist + if test ! -d $2 + then + echo "mkdir -p $2" + mkdir -p $2 + fi + + for file in $1 + do + # Remove existing files + if test -d "$2/$file" + then + echo "rm -rf $2/$file" + rm -rf "$2/$file" + fi + + # Downloading tar + if test ! -e "$2/${file}.tar.gz" + then + # Download + echo "Downloading ${file}.tar.gz" + wget -P $2 "http://corpus.canterbury.ac.nz/resources/${file}.tar.gz" + else + echo "${file}.tar.gz already exists, skipping" + fi + + # Make directory + echo "mkdir -p $2/$file" + mkdir -p "$2/$file" + + # Extract files + echo "Extracting $2/${file}.tar.gz" + tar xf "$2/${file}.tar.gz" -C "$2/$file" + done +} + +download_and_unzip "$CORPORA" $BASE_DIR diff --git a/src/Streamly/Internal/LZ4.hs b/src/Streamly/Internal/LZ4.hs new file mode 100644 --- /dev/null +++ b/src/Streamly/Internal/LZ4.hs @@ -0,0 +1,650 @@ +{-# LANGUAGE NamedFieldPuns #-} +-- | +-- Module : Streamly.Internal.LZ4 +-- Copyright : (c) 2020 Composewell Technologies +-- License : Apache-2.0 +-- Maintainer : streamly@composewell.com +-- Stability : experimental +-- Portability : GHC +-- +-- LZ4 compression and decompression routines. +-- +module Streamly.Internal.LZ4 + ( + -- * Foreign + c_createStream + , c_freeStream + , c_createStreamDecode + , c_freeStreamDecode + + -- * Block compression and decompression + , compressChunk + , decompressChunk + + -- * Stream compression and decompression + , compressChunksD + , resizeChunksD + , decompressChunksRawD + , decompressChunksWithD + + -- * Parsing LZ4 Frames + , simpleFrameParserD + ) + +where + +-------------------------------------------------------------------------------- +-- Imports +-------------------------------------------------------------------------------- + +import Control.Monad (when) +import Control.Monad.Catch (MonadThrow) +import Control.Monad.IO.Class (MonadIO(..)) +import Data.Bifunctor (second) +import Data.Bits (Bits(..)) +import Data.Coerce (coerce) +import Data.Int (Int32) +import Data.Word (Word32, Word8, byteSwap32) +import Foreign.C (CInt(..), CString) +import Foreign.ForeignPtr (plusForeignPtr, withForeignPtr) +import Foreign.Ptr (Ptr, castPtr, plusPtr) +import Foreign.Storable (peek, poke) +import Fusion.Plugin.Types (Fuse (..)) +import System.IO.Unsafe (unsafePerformIO) + +import qualified Streamly.Internal.Data.Array.Foreign as Array +import qualified Streamly.Internal.Data.Array.Foreign.Type as Array +import qualified Streamly.Internal.Data.Array.Foreign.Mut.Type as MArray +import qualified Streamly.Internal.Data.Parser.ParserD as Parser +import qualified Streamly.Internal.Data.Fold as Fold +import qualified Streamly.Internal.Data.Stream.StreamD as Stream +import qualified Streamly.Internal.Data.Array.Stream.Foreign as ArrayStream +import qualified Streamly.Internal.Data.Array.Stream.Fold.Foreign as ArrayFold + +import Streamly.Internal.LZ4.Config + +-------------------------------------------------------------------------------- +-- CPP helpers +-------------------------------------------------------------------------------- + +-- Simple helpers for more informative inline statements. + +#define INLINE_EARLY INLINE [2] +#define INLINE_NORMAL INLINE [1] +#define INLINE_LATE INLINE [0] + +-------------------------------------------------------------------------------- +-- Endianess +-------------------------------------------------------------------------------- + +{-# NOINLINE isLittleEndianMachine #-} +isLittleEndianMachine :: Bool +isLittleEndianMachine = + let lsb = head $ Array.toList $ Array.asBytes $ Array.fromList [1 :: Word32] + in lsb == 1 + +{-# INLINE toLittleEndian #-} +toLittleEndian :: Int32 -> Int32 +toLittleEndian i32 + | isLittleEndianMachine = i32 + | otherwise = fromIntegral (byteSwap32 (fromIntegral i32)) + +{-# INLINE fromLittleEndian #-} +fromLittleEndian :: Int32 -> Int32 +fromLittleEndian = toLittleEndian + +-------------------------------------------------------------------------------- +-- Foreign +-------------------------------------------------------------------------------- + +data C_LZ4Stream + +data C_LZ4StreamDecode + +-- | Exported for unit tests +foreign import ccall unsafe "lz4.h LZ4_createStream" + c_createStream :: IO (Ptr C_LZ4Stream) + +-- | Exported for unit tests +foreign import ccall unsafe "lz4.h LZ4_freeStream" + c_freeStream :: Ptr C_LZ4Stream -> IO () + +-- | Exported for unit tests +foreign import ccall unsafe "lz4.h LZ4_createStreamDecode" + c_createStreamDecode :: IO (Ptr C_LZ4StreamDecode) + +-- | Exported for unit tests +foreign import ccall unsafe "lz4.h LZ4_freeStreamDecode" + c_freeStreamDecode :: Ptr C_LZ4StreamDecode -> IO () + +foreign import ccall unsafe "lz4.h LZ4_compressBound" + c_compressBound :: CInt -> IO CInt + +foreign import ccall unsafe "lz4.h LZ4_compress_fast_continue" + c_compressFastContinue + :: Ptr C_LZ4Stream + -> CString + -> Ptr Word8 + -> CInt + -> CInt + -> CInt + -> IO CInt + +foreign import ccall unsafe "lz4.h LZ4_decompress_safe_continue" + c_decompressSafeContinue + :: Ptr C_LZ4StreamDecode + -> CString + -> Ptr Word8 + -> CInt + -> CInt + -> IO CInt + +foreign import capi + "lz4.h value LZ4_MAX_INPUT_SIZE" lz4_MAX_INPUT_SIZE :: CInt + +lz4_MAX_OUTPUT_SIZE :: CInt +lz4_MAX_OUTPUT_SIZE = + min (unsafePerformIO $ c_compressBound lz4_MAX_INPUT_SIZE) maxBound + +-------------------------------------------------------------------------------- +-- Conversion helpers +-------------------------------------------------------------------------------- + +{-# INLINE cIntToInt #-} +cIntToInt :: CInt -> Int +cIntToInt = fromIntegral + +{-# INLINE unsafeIntToCInt #-} +unsafeIntToCInt :: Int -> CInt +unsafeIntToCInt = fromIntegral + +{-# INLINE i32ToInt #-} +i32ToInt :: Int32 -> Int +i32ToInt = fromIntegral + +{-# INLINE cIntToI32 #-} +cIntToI32 :: CInt -> Int32 +cIntToI32 = coerce + +{-# INLINE i32ToCInt #-} +i32ToCInt :: Int32 -> CInt +i32ToCInt = coerce + +------------------------------------------------------------------------------- +-- Block Configuration access +------------------------------------------------------------------------------- + +metaSize :: BlockConfig -> Int +metaSize BlockConfig {blockSize} = + case blockSize of + BlockHasSize -> 8 + _ -> 4 + +setUncompSize :: BlockConfig -> Ptr Word8 -> Int32 -> IO () +setUncompSize BlockConfig {blockSize} = + case blockSize of + BlockHasSize -> \src -> poke (castPtr src `plusPtr` 4) . toLittleEndian + _ -> \_ _ -> return () + +getUncompSize :: BlockConfig -> Ptr Word8 -> IO Int32 +getUncompSize BlockConfig {blockSize} = + case blockSize of + BlockHasSize -> + \src -> + fromLittleEndian <$> peek (castPtr src `plusPtr` 4 :: Ptr Int32) + BlockMax64KB -> \_ -> return $ 64 * 1024 + BlockMax256KB -> \_ -> return $ 256 * 1024 + BlockMax1MB -> \_ -> return $ 1024 * 1024 + BlockMax4MB -> \_ -> return $ 4 * 1024 * 1024 + +dataOffset :: BlockConfig -> Int +dataOffset BlockConfig {blockSize} = + case blockSize of + BlockHasSize -> 8 + _ -> 4 + +compSizeOffset :: BlockConfig -> Int +compSizeOffset _ = 0 + +-------------------------------------------------------------------------------- +-- Block level compression and decompression +-------------------------------------------------------------------------------- + +-- Having NOINLINE here does not effect the performance a lot. Every +-- iteration of the loop is a little slower (< 1us) but the entire loop +-- fuses. +-- On a stream with 404739 elements of 10 bytes each, +-- With NOINLINE: 96.14 ms +-- With INLINE: 81.07 ms +-- +-- With INLINE statement and the usage of fusion-plugin results in an +-- enormous code size when used with other combinators. +-- +-- | Compress an array of Word8. The compressed block header depends on the +-- 'BlockConfig' setting. +{-# NOINLINE compressChunk #-} +compressChunk :: + BlockConfig + -> Int + -> Ptr C_LZ4Stream + -> Array.Array Word8 + -> IO (Array.Array Word8) +compressChunk cfg speed ctx arr = do + Array.unsafeAsPtr arr + $ \src -> do + let uncompLen = Array.byteLength arr + speedC = unsafeIntToCInt speed + when (uncompLen > maxBlockSize) + $ error $ "compressChunk: Source array length " + ++ show uncompLen + ++ " exceeds the maximum block size of " + ++ show maxBlockSize + -- The size is safe to downcast + let uncompLenC = unsafeIntToCInt uncompLen + maxCompLenC <- c_compressBound uncompLenC + let maxCompLen = cIntToInt maxCompLenC + when (maxCompLenC <= 0) + $ error $ "compressChunk: compressed length <= 0." + ++ " maxCompLenC: " ++ show maxCompLenC + ++ " uncompLenC: " ++ show uncompLenC + (MArray.Array fptr dstBegin dstMax) <- + MArray.newArray (maxCompLen + metaSize_) + let hdrCompLen = dstBegin `plusPtr` compSizeOffset_ + compData = dstBegin `plusPtr` dataOffset_ + compLenC <- + c_compressFastContinue + ctx src compData uncompLenC maxCompLenC speedC + when (compLenC <= 0) + $ error $ "compressChunk: c_compressFastContinue failed. " + ++ "uncompLenC: " ++ show uncompLenC + ++ "compLenC: " ++ show compLenC + setUncompSize_ dstBegin (cIntToI32 uncompLenC) + poke hdrCompLen (toLittleEndian (cIntToI32 compLenC)) + let compLen = cIntToInt compLenC + dstEnd = dstBegin `plusPtr` (compLen + metaSize_) + compArr = MArray.Array fptr dstEnd dstMax + -- It is safe to shrink here as we need to hold the last 64KB of + -- the previous uncompressed array and not the compressed one. + Array.unsafeFreeze <$> MArray.shrinkToFit compArr + where + + metaSize_ = metaSize cfg + compSizeOffset_ = compSizeOffset cfg + dataOffset_ = dataOffset cfg + setUncompSize_ = setUncompSize cfg + maxBlockSize = + case blockSize cfg of + BlockHasSize -> cIntToInt lz4_MAX_INPUT_SIZE + BlockMax64KB -> 64 * 1024 + BlockMax256KB -> 256 * 1024 + BlockMax1MB -> 1024 * 1024 + BlockMax4MB -> 4 * 1024 * 1024 + +-- Having NOINLINE here does not effect the performance a lot. Every +-- iteration of the loop is a little slower (< 1us) but the entire loop +-- fuses. +-- +-- With INLINE statement and the usage of fusion-plugin results in an +-- enormous code size when used with other combinators. +-- | Primitive function to decompress a chunk of Word8. +{-# NOINLINE decompressChunk #-} +decompressChunk :: + BlockConfig + -> Ptr C_LZ4StreamDecode + -> Array.Array Word8 + -> IO (Array.Array Word8) +decompressChunk cfg ctx arr = do + Array.unsafeAsPtr arr + $ \src -> do + let hdrCompLen :: Ptr Int32 = src `plusPtr` compSizeOffset cfg + compData = src `plusPtr` dataOffset cfg + arrDataLen = Array.byteLength arr - metaSize cfg + uncompLenC <- i32ToCInt <$> getUncompSize cfg src + compLenC <- i32ToCInt . fromLittleEndian <$> peek hdrCompLen + let compLen = cIntToInt compLenC + maxCompLenC = lz4_MAX_OUTPUT_SIZE + uncompLen = cIntToInt uncompLenC + + -- Error checks + if compLenC <= 0 + then error "decompressChunk: compressed data length > 2GB" + else if compLen < arrDataLen + then error $ "decompressChunk: input array data length " + ++ show arrDataLen ++ " is less than " + ++ "the compressed data length specified in the header " + ++ show compLen + else when (compLenC > maxCompLenC) $ + error $ "decompressChunk: compressed data length is more " + ++ "than the max limit: " ++ show maxCompLenC + + (MArray.Array fptr dstBegin dstMax) <- MArray.newArray uncompLen + decompLenC <- + c_decompressSafeContinue + ctx compData dstBegin compLenC uncompLenC + when (decompLenC < 0) + $ error $ "decompressChunk: c_decompressSafeContinue failed. " + ++ "\narrDataLen = " ++ show arrDataLen + ++ "\ncompLenC = " ++ show compLenC + ++ "\nuncompLenC = " ++ show uncompLenC + ++ "\ndecompLenC = " ++ show decompLenC + let decompLen = cIntToInt decompLenC + dstEnd = dstBegin `plusPtr` decompLen + decompArr = MArray.Array fptr dstEnd dstMax + -- We cannot shrink the array here, because that would reallocate + -- the array invalidating the cached dictionary. + return $ Array.unsafeFreeze decompArr + +-------------------------------------------------------------------------------- +-- Stream compression +-------------------------------------------------------------------------------- + +{-# ANN type CompressState Fuse #-} +data CompressState st ctx prev + = CompressInit st + | CompressDo st ctx prev + | CompressDone ctx + +-- 64KB blocks are optimal as the dictionary max size is 64KB. We can rechunk +-- the stream into 64KB blocks before compression. +-- +-- | See 'Streamly.LZ4.compress' for documentation. +{-# INLINE_NORMAL compressChunksD #-} +compressChunksD :: + MonadIO m + => BlockConfig + -> Int + -> Stream.Stream m (Array.Array Word8) + -> Stream.Stream m (Array.Array Word8) +compressChunksD cfg speed0 (Stream.Stream step0 state0) = + Stream.Stream step (CompressInit state0) + + where + + speed = max speed0 0 + + {-# INLINE_LATE step #-} + step _ (CompressInit st) = + liftIO + $ do + ctx <- c_createStream + -- Instead of using an external dictionary we could just hold + -- the previous chunks. However, the dictionary is only 64KB, + -- if the chunk size is bigger we would be holding a lot more + -- data than required. Also, the perf advantage does not seem + -- much. + return $ Stream.Skip $ CompressDo st ctx Nothing + step gst (CompressDo st ctx prev) = do + r <- step0 gst st + case r of + Stream.Yield arr st1 -> + -- The compression primitives use 32-bit signed int (CInt) to + -- represent the length of the array. The maximum value of a + -- 32-bit signed int is 2GB. + if Array.byteLength arr >= 2 * 1024 * 1024 * 1024 + then error "compressChunksD: Array element > 2 GB encountered" + else do + arr1 <- liftIO $ compressChunk cfg speed ctx arr + -- XXX touch the "prev" array to keep it alive? + return $ Stream.Yield arr1 (CompressDo st1 ctx (Just arr)) + Stream.Skip st1 -> + return $ Stream.Skip $ CompressDo st1 ctx prev + Stream.Stop -> return $ Stream.Skip $ CompressDone ctx + step _ (CompressDone ctx) = + liftIO $ c_freeStream ctx >> return Stream.Stop + +-------------------------------------------------------------------------------- +-- Stream decompression +-------------------------------------------------------------------------------- + +{-# INLINE endMark #-} +endMark :: Int32 +endMark = 0 + +footerSize :: FrameConfig -> Int +footerSize FrameConfig {hasEndMark} = + if hasEndMark + then 4 + else 0 + +validateFooter :: FrameConfig -> Array.Array Word8 -> IO Bool +validateFooter _ _ = return True + +{-# ANN type ResizeState Fuse #-} +data ResizeState st arr + = RInit st + | RProcess st arr + | RAccumulate st arr + | RFooter st arr + | RYield arr (ResizeState st arr) + | RDone + +-- | Look for a compressed block header and compact the arrays in the input +-- stream to the compressed length specified in the header. The output contains +-- arrays, where each array represents a full single compressed block along +-- with the compression header. +-- +-- The resize operation is idempotent: +-- +-- @resizeChunksD . resizeChunksD = resizeChunksD@ +-- +{-# INLINE_NORMAL resizeChunksD #-} +resizeChunksD :: + MonadIO m + => BlockConfig + -> FrameConfig + -> Stream.Stream m (Array.Array Word8) + -> Stream.Stream m (Array.Array Word8) +resizeChunksD cfg conf (Stream.Stream step0 state0) = + Stream.Stream step (RInit state0) + + where + + metaSize_ = metaSize cfg + compSizeOffset_ = compSizeOffset cfg + + hasEndMark_ = hasEndMark conf + footerSize_ = footerSize conf + validateFooter_ = validateFooter conf + + -- Unsafe function + {-# INLINE isEndMark #-} + isEndMark src + | hasEndMark_ = do + em <- peek (castPtr src :: Ptr Int32) + return $ em == endMark + | otherwise = return False + + {-# INLINE process #-} + process st arr@(Array.Array fb e) = do + let len = Array.byteLength arr + if len < 4 + then return $ Stream.Skip $ RAccumulate st arr + else withForeignPtr fb $ \b -> do + res <- isEndMark b + if res + then return $ Stream.Skip $ RFooter st arr + else do + if len <= metaSize_ + then return $ Stream.Skip $ RAccumulate st arr + else do + let compLenPtr = castPtr (b `plusPtr` compSizeOffset_) + compressedSize <- + i32ToInt . fromLittleEndian <$> peek compLenPtr + let required = compressedSize + metaSize_ + if len == required + then return $ Stream.Skip $ RYield arr $ RInit st + else if len < required + then return $ Stream.Skip $ RAccumulate st arr + else do + let arr1E = b `plusPtr` required + arr1 = Array.Array fb arr1E + arr2S = fb `plusForeignPtr` required + arr2 = Array.Array arr2S e + return $ Stream.Skip $ RYield arr1 $ RProcess st arr2 + + {-# INLINE_LATE step #-} + step _ (RYield r next) = return $ Stream.Yield r next + step gst (RInit st) = do + r <- step0 gst st + case r of + Stream.Yield arr st1 -> liftIO $ process st1 arr + Stream.Skip st1 -> return $ Stream.Skip $ RInit st1 + Stream.Stop -> + if hasEndMark_ + then error "resizeChunksD: No end mark found" + else return Stream.Stop + step _ (RProcess st arr) = liftIO $ process st arr + step gst (RAccumulate st buf) = do + r <- step0 gst st + case r of + Stream.Yield arr st1 -> do + arr1 <- Array.spliceTwo buf arr + liftIO $ process st1 arr1 + Stream.Skip st1 -> return $ Stream.Skip $ RAccumulate st1 buf + Stream.Stop -> error "resizeChunksD: Incomplete block" + step gst (RFooter st buf) = do + -- Warn if len > footerSize + let len = Array.byteLength buf + if len < footerSize_ + then do + r <- step0 gst st + case r of + Stream.Yield arr st1 -> do + arr1 <- Array.spliceTwo buf arr + return $ Stream.Skip $ RFooter st1 arr1 + Stream.Skip st1 -> return $ Stream.Skip $ RFooter st1 buf + Stream.Stop -> error "resizeChunksD: Incomplete footer" + else do + res <- liftIO $ validateFooter_ buf + if res + then return Stream.Stop + else error "resizeChunksD: Invalid footer" + step _ RDone = return Stream.Stop + +{-# ANN type DecompressState Fuse #-} +data DecompressState st ctx prev + = DecompressInit st + | DecompressDo st ctx prev + | DecompressDone ctx + +-- | This combinator assumes all the arrays in the incoming stream are properly +-- resized. +-- +-- This combinator works well with untouched arrays compressed with +-- 'compressChunksD'. A random compressed stream would first need to be +-- resized properly with 'resizeChunksD'. +-- +{-# INLINE_NORMAL decompressChunksRawD #-} +decompressChunksRawD :: + MonadIO m + => BlockConfig + -> Stream.Stream m (Array.Array Word8) + -> Stream.Stream m (Array.Array Word8) +decompressChunksRawD cfg (Stream.Stream step0 state0) = + Stream.Stream step (DecompressInit state0) + + where + + {-# INLINE_LATE step #-} + step _ (DecompressInit st) = + liftIO + $ do + lz4Ctx <- c_createStreamDecode + return $ Stream.Skip $ DecompressDo st lz4Ctx Nothing + step _ (DecompressDone lz4Ctx) = + liftIO $ c_freeStreamDecode lz4Ctx >> return Stream.Stop + step gst (DecompressDo st lz4Ctx prev) = do + r <- step0 gst st + case r of + Stream.Yield arr st1 -> do + arr1 <- liftIO $ decompressChunk cfg lz4Ctx arr + -- Instead of the input array chunk we need to hold the output + -- array chunk here. + return $ Stream.Yield arr1 (DecompressDo st1 lz4Ctx (Just arr1)) + Stream.Skip st1 -> + return $ Stream.Skip $ DecompressDo st1 lz4Ctx prev + Stream.Stop -> return $ Stream.Skip $ DecompressDone lz4Ctx + +decompressChunksWithD :: + (MonadThrow m, MonadIO m) + => Parser.Parser m Word8 (BlockConfig, FrameConfig) + -> Stream.Stream m (Array.Array Word8) + -> Stream.Stream m (Array.Array Word8) +decompressChunksWithD p s = do + ((cfg, config), next) <- Stream.fromEffect $ second Stream.toStreamD + <$> ArrayStream.fold_ (ArrayFold.fromParser p) (Stream.fromStreamD s) + decompressChunksRawD cfg (resizeChunksD cfg config next) + +-- XXX Merge this with BlockConfig? +data FLG = + FLG + { isBlockIndependent :: Bool + , hasBlockChecksum :: Bool + , hasContentSize :: Bool + , hasContentChecksum :: Bool + , hasDict :: Bool + } + +-- XXX Support Skippable frames +simpleFrameParserD :: + (Monad m, MonadThrow m) + => Parser.Parser m Word8 (BlockConfig, FrameConfig) +simpleFrameParserD = do + _ <- assertMagic + _flg <- parseFLG + blockMaxSize <- parseBD + _ <- assertHeaderChecksum + let config = + (BlockConfig {blockSize = blockMaxSize} + , FrameConfig {hasEndMark = True}) + Parser.fromPure config + + where + + assertHeaderChecksum = Parser.satisfy (const True) + + assertMagic = do + let magic = 407708164 :: Int + magic_ <- + let w8ToInt = fromIntegral :: Word8 -> Int + stp (i, b) a = (i + 8, b + w8ToInt a * 2 ^ i) :: (Int, Int) + fld = Fold.foldl' stp (0, 0) + in Parser.takeEQ 4 (snd <$> fld) + if magic_ == magic + then Parser.fromPure () + else Parser.die + ("The parsed magic " + ++ show magic_ ++ " does not match " ++ show magic) + + parseFLG = do + a <- Parser.satisfy (const True) + let isVersion01 = not (testBit a 7) && testBit a 6 + let flg = + FLG + (testBit a 5) + (testBit a 4) + (testBit a 3) + (testBit a 2) + (testBit a 0) + if isVersion01 + then if isBlockIndependent flg + then Parser.die "Block independence is not yet supported" + else if hasBlockChecksum flg + then Parser.die "Block checksum is not yet supported" + else if hasContentSize flg + then Parser.die "Content size is not yet supported" + else if hasContentChecksum flg + then Parser.die "Content checksum is not yet supported" + else if hasDict flg + then Parser.die "Dict is not yet supported" + else Parser.fromPure flg + else Parser.die "Version is not 01" + + parseBD = do + a <- Parser.satisfy (const True) + case shiftR a 4 of + 4 -> Parser.fromPure BlockMax64KB + 5 -> Parser.fromPure BlockMax256KB + 6 -> Parser.fromPure BlockMax1MB + 7 -> Parser.fromPure BlockMax4MB + _ -> Parser.die "parseBD: Unknown block max size" diff --git a/src/Streamly/Internal/LZ4/Config.hs b/src/Streamly/Internal/LZ4/Config.hs new file mode 100644 --- /dev/null +++ b/src/Streamly/Internal/LZ4/Config.hs @@ -0,0 +1,161 @@ +-- | +-- Module : Streamly.Internal.LZ4.Config +-- Copyright : (c) 2020 Composewell Technologies +-- License : Apache-2.0 +-- Maintainer : streamly@composewell.com +-- Stability : experimental +-- Portability : GHC +-- +-- Frame and block configuration settings for LZ4. +-- +module Streamly.Internal.LZ4.Config + ( + -- * LZ4 Frame Format + -- | Configuration for a frame consisting of a series of blocks. + FrameConfig(..) + , setFrameContentSize + , setFrameContentChecksum + , setFrameDictionaryId + , setFrameBlockIndependence + , setFrameBlockChecksum + , setFrameEndMark + , defaultFrameConfig + + -- * LZ4 Block Format + -- | Configuration for a single compressed block. + , BlockConfig(..) + , BlockSize(..) + , setBlockMaxSize + , setBlockIndependence + , setBlockChecksum + , defaultBlockConfig + ) + +where + +-------------------------------------------------------------------------------- +-- Frame Configuration +-------------------------------------------------------------------------------- + +-- | Defines the LZ4 frame format. +newtype FrameConfig = + FrameConfig + { hasEndMark :: Bool + } + +-- Header fields + +-- | Whether the frame header has a content size field. +-- +-- /Unimplemented/ +setFrameContentSize :: Bool -> FrameConfig -> FrameConfig +setFrameContentSize = undefined + +-- | Whether the frame header has a dictionary ID field. +-- +-- /Unimplemented/ +setFrameDictionaryId :: Bool -> FrameConfig -> FrameConfig +setFrameDictionaryId = undefined + +-- | When 'False', future blocks in the frame may depend on the past blocks. +-- Block dependency improves compression ratio, especially for small blocks. On +-- the other hand, it makes random access or multi-threaded decoding +-- impossible. +-- +-- /Unimplemented/ +setFrameBlockIndependence :: Bool -> FrameConfig -> FrameConfig +setFrameBlockIndependence = undefined + +-- | Indicate whether blocks in the frame are followed by a 4-byte checksum +-- field. +-- +-- /Unimplemented/ +setFrameBlockChecksum :: Bool -> FrameConfig -> FrameConfig +setFrameBlockChecksum = undefined + +-- Footer fields + +-- | Whether the frame footer has an end mark. +setFrameEndMark :: Bool -> FrameConfig -> FrameConfig +setFrameEndMark val cfg = cfg {hasEndMark = val} + +-- | Whether the frame footer has a content checksum after the end mark. If it +-- is True then it implicitly indicates that setEndMark is set to True. +-- +-- /Unimplemented/ +setFrameContentChecksum :: Bool -> FrameConfig -> FrameConfig +setFrameContentChecksum = undefined + +-- XXX setEndMark should be True by default to conform to the standard. +-- +-- | The default settings are: +-- +-- * 'setFrameContentSize' 'False' +-- * 'setFrameDictionaryId' 'False' +-- * 'setFrameBlockIndependence' 'False' +-- * 'setFrameBlockChecksum' 'False' +-- * 'setFrameEndMark' 'False' +-- +defaultFrameConfig :: FrameConfig +defaultFrameConfig = FrameConfig + { hasEndMark = False + } + +-------------------------------------------------------------------------------- +-- Block Configuration +-------------------------------------------------------------------------------- + +-- | Maximum uncompressed size of a data block. +data BlockSize = + BlockHasSize -- ^ Block header has uncompressed size after the compressed + -- size field. Please note that this option is not in the + -- LZ4 specification. + | BlockMax64KB + | BlockMax256KB + | BlockMax1MB + | BlockMax4MB + +-- | Defines the LZ4 compressed block format. Please note that the +-- @Uncompressed length@ field is optional and not in the LZ4 specification. +-- +-- @ +-- ---------------------------------------------------------------------- +-- | Compressed length | Uncompressed length | Data | Checksum | +-- | (4 byte) | (4 byte) (optional) | | (4 byte) (optional) | +-- ---------------------------------------------------------------------- +-- @ +-- +-- Compressed length is the length of the @Data@ field only. Uncompressed +-- length is present only when the 'setBlockMaxSize' is set to 'BlockHasSize'. +-- Checksum is present when 'setBlockChecksum' is set to 'True'. The 4-byte +-- fields are stored in machine byte order. +-- +newtype BlockConfig = + BlockConfig + { blockSize :: BlockSize + } + +-- | Set the maximum uncompressed size of the data block. +setBlockMaxSize :: BlockSize -> BlockConfig -> BlockConfig +setBlockMaxSize bs cfg = cfg {blockSize = bs} + +-- | When 'False', the block may depend on the past blocks. +-- +-- /Unimplemented/ +setBlockIndependence :: Bool -> BlockConfig -> BlockConfig +setBlockIndependence = undefined + +-- | Indicate whether the block is followed by a 4-byte checksum field. +-- +-- /Unimplemented/ +setBlockChecksum :: Bool -> BlockConfig -> BlockConfig +setBlockChecksum = undefined + +-- | The default settings are: +-- +-- * 'setBlockMaxSize' 'BlockHasSize' +-- * 'setBlockIndependence' 'False' +-- * 'setBlockChecksum' 'False' +-- +defaultBlockConfig :: BlockConfig +defaultBlockConfig = BlockConfig {blockSize = BlockHasSize} diff --git a/src/Streamly/LZ4.hs b/src/Streamly/LZ4.hs new file mode 100644 --- /dev/null +++ b/src/Streamly/LZ4.hs @@ -0,0 +1,122 @@ +-- | +-- Module : Streamly.LZ4 +-- Copyright : (c) 2020 Composewell Technologies +-- License : Apache-2.0 +-- Maintainer : streamly@composewell.com +-- Stability : experimental +-- Portability : GHC +-- +-- Streaming APIs for LZ4 () compression and +-- decompression. +-- +-- A compressed LZ4 object (e.g. a file) may be represented by a sequence of +-- one or more LZ4 frames defined by the [LZ4 frame +-- format](https://github.com/lz4/lz4/blob/dev/doc/lz4_Frame_format.md). A +-- frame consists of a frame header followed by a number of compressed blocks +-- and a frame footer. The frame header defines the attributes of the +-- compression method and the blocks in the frame. For example, the blocks may +-- be independently compressed or future blocks may depend on the past blocks. +-- It may also describe the maximum size of the blocks in the frame and use of +-- some optional features. +-- +-- This module exposes combinators to only compress or decompress the stream of +-- blocks in a frame and not the frame itself. See the "Streamly.Internal.LZ4" +-- module for an experimental frame parsing function. +-- +-- How the blocks are encoded, depends on the attributes specified in the frame +-- header. We provide a 'BlockConfig' parameter to specify those options when +-- decoding or encoding a stream of blocks. Assuming you have parsed the frame, +-- you can set the 'BlockConfig' accordingly to parse the stream of blocks +-- appropriately. +-- +-- Please build with +-- [fusion-plugin](https://hackage.haskell.org/package/fusion-plugin) for best +-- performance. See the [streamly build +-- guide](https://streamly.composewell.com/streamly-0.8.0/Compiling.html) for +-- more details. +-- +-- The APIs are not yet stable and may change in future. +-- +module Streamly.LZ4 + ( + -- * Configuration + BlockConfig + , defaultBlockConfig + , BlockSize(..) + , setBlockMaxSize + + -- * Combinators + , compressChunks + , decompressChunks + ) + +where + +import Control.Monad.IO.Class (MonadIO) +import Data.Word (Word8) +import Streamly.Internal.Data.Array.Foreign (Array) +import Streamly.Internal.Data.Stream.StreamD (fromStreamD, toStreamD) +import Streamly.Prelude (SerialT) + +import Streamly.Internal.LZ4.Config +import Streamly.Internal.LZ4 + +-------------------------------------------------------------------------------- +-- Compression +-------------------------------------------------------------------------------- + +-- Note that "speedup" is specific to compression, therefore, it is not part of +-- BlockConfig. +-- +-- XXX Ensure little-endian byte order as per the spec +-- XXX Check the size of the input array and fail if it is more than the max +-- block size set in BlockConfig. + +-- | @compressChunks config speedup stream@ compresses an input stream of +-- @Array word8@ using the configuration defined by @config@. The resulting +-- stream is of type @Array Word8@ where each array represents a compressed +-- input block. Each input array becomes one compressed block. +-- +-- @speedup@ is a compression speedup factor, more the value of @speedup@ +-- faster the compression but the size of compressed data may increase. The +-- factor should be between 1 and 65537 inclusive, if it is less than 1 it is +-- set to 1 if it is more than 65537 then it is set to 65537. +-- +-- LZ4 does not allow an uncompressed block of size more than 2,113,929,216 +-- (0x7E000000) bytes (a little less than 2GiB). If the compressed block +-- length is more than maximum uncompressed block length (approximately 2GiB) +-- it would result in a decompression error. +-- +-- See 'BlockConfig' for more details about the format of the compressed block. +-- +-- /Since 0.1.0/ +{-# INLINE compressChunks #-} +compressChunks :: + MonadIO m + => BlockConfig + -> Int + -> SerialT m (Array Word8) + -> SerialT m (Array Word8) +compressChunks cfg i m = fromStreamD (compressChunksD cfg i (toStreamD m)) + +-------------------------------------------------------------------------------- +-- Decompression +-------------------------------------------------------------------------------- + +-- | Decompress a stream of @Array Word8@ compressed using LZ4 stream +-- compression. See 'compressChunks' for the format of the input blocks. The +-- input chunks could be of any size, they are resized to the appropriate block +-- size before decompression based on block headers. The decompressed output +-- arrays correspond to one compressed block each. +-- +-- /Since 0.1.0/ +{-# INLINE decompressChunks #-} +decompressChunks :: + MonadIO m + => BlockConfig + -> SerialT m (Array Word8) + -> SerialT m (Array Word8) +decompressChunks bf = + fromStreamD + . decompressChunksRawD bf + . resizeChunksD bf defaultFrameConfig . toStreamD diff --git a/streamly-lz4.cabal b/streamly-lz4.cabal new file mode 100644 --- /dev/null +++ b/streamly-lz4.cabal @@ -0,0 +1,100 @@ +cabal-version: 2.2 +name: streamly-lz4 +version: 0.1.0 +synopsis: Streamly combinators for LZ4 compression +description: + Compress and decompress streams of data using LZ4 compression. See + . +license: Apache-2.0 +license-file: LICENSE +homepage: https://github.com/composewell/streamly-lz4 +bug-reports: https://github.com/composewell/streamly-lz4/issues +author: Composewell Technologies +maintainer: streamly@composewell.com +copyright: 2020 Composewell Technologies +category: Codec, Compression, Streamly +build-type: Simple +tested-with: GHC==8.2.2 + , GHC==8.4.4 + , GHC==8.6.5 + , GHC==8.8.4 + , GHC==8.10.7 + , GHC==9.0.1 +extra-source-files: CHANGELOG.md + , NOTICE + , README.md + , cbits/lz4.h + , download-corpora.sh + +flag fusion-plugin + description: Use fusion plugin for benchmarks and executables + manual: True + default: False + +source-repository head + type: git + location: https://github.com/composewell/streamly-lz4 + +common optimization-options + ghc-options: -O2 + -fdicts-strict + -fspec-constr-recursive=16 + -fmax-worker-args=16 + +common exe-options + import: optimization-options + if flag(fusion-plugin) && !impl(ghc < 8.6) + ghc-options: -fplugin Fusion.Plugin + build-depends: fusion-plugin >= 0.2 && < 0.3 + +library + import: optimization-options + hs-source-dirs: src + include-dirs: cbits + c-sources: cbits/lz4.c + exposed-modules: Streamly.LZ4 + , Streamly.Internal.LZ4 + , Streamly.Internal.LZ4.Config + build-depends: base >= 4 && < 5 + , fusion-plugin-types >= 0.1 && < 0.2 + , exceptions >= 0.8 && < 0.11 + , streamly >= 0.8 && < 0.9 + ghc-options: -Wall + default-language: Haskell2010 + default-extensions: + CPP + CApiFFI + EmptyDataDecls + ForeignFunctionInterface + ScopedTypeVariables + RecordWildCards + TypeInType + FlexibleContexts + +test-suite test-lz4 + type: exitcode-stdio-1.0 + hs-source-dirs: test + main-is: Main.hs + build-depends: streamly-lz4 + , streamly >= 0.8 && < 0.9 + , base >= 4 && < 5 + , QuickCheck >= 2.13.1 && < 2.15 + , hspec >= 2.7 && < 2.9 + , temporary >= 1.3 && < 1.4 + ghc-options: -fno-ignore-asserts -Wall -rtsopts +RTS -M200M -RTS + default-language: Haskell2010 + default-extensions: TypeInType + +benchmark bench-lz4 + import: exe-options + type: exitcode-stdio-1.0 + hs-source-dirs: benchmark + main-is: Main.hs + build-depends: streamly-lz4 + , streamly >= 0.8 && < 0.9 + , base >= 4 && < 5 + , gauge >= 0.2.5 && < 0.2.6 + , directory >= 1.3.0 && < 1.3.8 + ghc-options: -Wall + default-language: Haskell2010 + default-extensions: TypeInType diff --git a/test/Main.hs b/test/Main.hs new file mode 100644 --- /dev/null +++ b/test/Main.hs @@ -0,0 +1,306 @@ +-- | +-- Module : Streamly.Internal.LZ4.Config +-- Copyright : (c) 2020 Composewell Technologies +-- License : Apache-2.0 +-- Maintainer : streamly@composewell.com +-- Stability : experimental +-- Portability : GHC +-- +module Main (main) where + +import Control.Monad (forM_) +import Control.Monad.IO.Class (MonadIO(..)) +import Data.Word (Word8) +import Data.Function ((&)) +import Streamly.Internal.Data.Stream.StreamD (fromStreamD, toStreamD) +import System.IO (IOMode(..), openFile, hClose) +import System.IO.Temp (withSystemTempFile) +import Test.Hspec (describe, hspec, it, shouldBe) +import Test.QuickCheck (Property, forAll, property) +import Test.QuickCheck.Gen + ( Gen, choose, elements, frequency, generate, listOf, vectorOf ) +import Test.QuickCheck.Monadic (monadicIO) + +import qualified Streamly.Internal.Data.Array.Foreign.Type as Array +import qualified Streamly.Internal.Data.Stream.IsStream as Stream +import qualified Streamly.Internal.FileSystem.Handle as Handle + +import Streamly.Internal.LZ4.Config +import Streamly.Internal.LZ4 +import Streamly.LZ4 + +-- Choose only 0 and 1 so that we can get good compressible sequences. +genArrayW8List :: Gen [Array.Array Word8] +genArrayW8List = listOf $ Array.fromList <$> listOf (elements [0,1]) + +genArrayW8Large :: Gen (Array.Array Word8) +genArrayW8Large = do + let minArr = 1024 * 10 + maxArr = 1024 * 100 + arrS <- choose (minArr, maxArr) + Array.fromList <$> vectorOf arrS (elements [0,1]) + +-- HC : Highly compressible +genArrayW8LargeHC :: (Int, Int) -> Gen (Array.Array Word8) +genArrayW8LargeHC (min_, max_) = do + arrS <- choose (min_, max_) + Array.fromList <$> vectorOf arrS (frequency [(9, pure 0), (1, pure 1)]) + +genNonEmptyListWith :: Gen (Array.Array Word8) -> Gen [Array.Array Word8] +genNonEmptyListWith gen = do + sz <- choose (50, 100) + vectorOf sz gen + +genAcceleration :: Gen Int +genAcceleration = elements [-1..12] + +decompressCompressChunk :: BlockConfig -> Int -> Array.Array Word8 -> IO () +decompressCompressChunk conf i arr = do + lz4Ctx <- c_createStream + lz4CtxD <- c_createStreamDecode + compressed <- compressChunk conf i lz4Ctx arr + decompressed <- decompressChunk conf lz4CtxD compressed + c_freeStream lz4Ctx + c_freeStreamDecode lz4CtxD + decompressed `shouldBe` arr + +decompressCompressChunk2 :: + BlockConfig -> Int -> Array.Array Word8 -> Array.Array Word8 -> IO () +decompressCompressChunk2 conf i arr1 arr2 = do + lz4Ctx <- c_createStream + lz4CtxD <- c_createStreamDecode + compressed1 <- compressChunk conf i lz4Ctx arr1 + compressed2 <- compressChunk conf i lz4Ctx arr2 + decompressed1 <- decompressChunk conf lz4CtxD compressed1 + decompressed2 <- decompressChunk conf lz4CtxD compressed2 + c_freeStream lz4Ctx + c_freeStreamDecode lz4CtxD + (decompressed1, decompressed2) `shouldBe` (arr1, arr2) + +decompressResizedcompress :: BlockConfig -> Int -> [Array.Array Word8] -> IO () +decompressResizedcompress conf i lst = + let strm = Stream.fromList lst + in do lst1 <- + Stream.toList $ decompressChunksRaw $ compressChunks conf i strm + lst `shouldBe` lst1 + + where + + decompressChunksRaw = fromStreamD . decompressChunksRawD conf . toStreamD + +decompressCompress :: BlockConfig -> Int -> Int -> [Array.Array Word8] -> IO () +decompressCompress conf bufsize i lst = do + let strm = Stream.fromList lst + withSystemTempFile "LZ4" $ \tmp tmpH -> do + compressChunks conf i strm & Handle.putChunks tmpH + hClose tmpH + lst1 <- + Stream.toList + $ Stream.bracket_ (openFile tmp ReadMode) hClose + $ \h -> + Stream.unfold Handle.readChunksWithBufferOf (bufsize, h) + & decompressChunks conf + lst1 `shouldBe` lst + +{-# INLINE endMarkArr #-} +endMarkArr :: Array.Array Word8 +endMarkArr = Array.fromListN 4 [0,0,0,0] + +decompressCompressFrame :: + BlockConfig -> FrameConfig -> Int -> Int -> [Array.Array Word8] -> IO () +decompressCompressFrame bf ff bufsize i lst = do + let strm = Stream.fromList lst + withSystemTempFile "LZ4" $ \tmp tmpH -> do + compressChunksFrame strm & Handle.putChunks tmpH + hClose tmpH + lst1 <- + Stream.toList + $ Stream.bracket_ (openFile tmp ReadMode) hClose + $ \h -> + Stream.unfold Handle.readChunksWithBufferOf (bufsize, h) + & decompressChunksFrame + lst1 `shouldBe` lst + + where + + decompressChunksFrame + :: Stream.SerialT IO (Array.Array Word8) + -> Stream.SerialT IO (Array.Array Word8) + decompressChunksFrame = + fromStreamD . decompressChunksRawD bf . resizeChunksD bf ff . toStreamD + + compressChunksFrame + :: Stream.SerialT IO (Array.Array Word8) + -> Stream.SerialT IO (Array.Array Word8) + compressChunksFrame strm = + if hasEndMark ff + then (fromStreamD . compressChunksD bf i . toStreamD) strm + `Stream.append` Stream.fromPure endMarkArr + else (fromStreamD . compressChunksD bf i . toStreamD) strm + +decompressWithCompress :: Int -> Int -> [Array.Array Word8] -> IO () +decompressWithCompress bufsize i lst = do + -- Stream with header that returns the config + -- Magic Little endian (4 bytes) = 407708164 + let magicLE = [4, 34, 77, 24] + -- flg with everything unset + flg = 64 + -- bd with 64KB block max size + bd = 64 + headerChk = 0 + headerList = magicLE ++ [flg, bd, headerChk] + header = Stream.fromList headerList + headerArr <- Stream.fold (Array.writeN (length headerList)) header + (bf, ff) <- Stream.parseD simpleFrameParserD header + let strm = Stream.fromList lst + withSystemTempFile "LZ4" $ \tmp tmpH -> do + compressChunksFrame bf ff i strm + & Stream.cons headerArr + & Handle.putChunks tmpH + hClose tmpH + lst1 <- + Stream.toList + $ Stream.bracket_ (openFile tmp ReadMode) hClose + $ \h -> + Stream.unfold Handle.readChunksWithBufferOf (bufsize, h) + & decompressWith_ + lst1 `shouldBe` lst + + where + + compressChunksFrame + :: BlockConfig + -> FrameConfig + -> Int + -> Stream.SerialT IO (Array.Array Word8) + -> Stream.SerialT IO (Array.Array Word8) + compressChunksFrame bf ff i_ strm = + if hasEndMark ff + then (fromStreamD . compressChunksD bf i_ . toStreamD) strm + `Stream.append` Stream.fromPure endMarkArr + else (fromStreamD . compressChunksD bf i_ . toStreamD) strm + + decompressWith_ :: + Stream.SerialT IO (Array.Array Word8) + -> Stream.SerialT IO (Array.Array Word8) + decompressWith_ = + fromStreamD . decompressChunksWithD simpleFrameParserD . toStreamD + +resizeIdempotence :: BlockConfig -> Property +resizeIdempotence conf = + forAll ((,) <$> genAcceleration <*> genArrayW8List) + $ \(acc, w8List) -> do + let strm = compressChunks conf acc $ Stream.fromList w8List + f1 <- Stream.toList $ resizeChunks strm + f2 <- Stream.toList $ foldr ($) strm $ replicate acc resizeChunks + f1 `shouldBe` f2 + + where + + resizeChunks = + fromStreamD . resizeChunksD conf defaultFrameConfig . toStreamD + +main :: IO () +main = do + large <- generate $ genNonEmptyListWith genArrayW8Large + largeHC <- + generate + $ genNonEmptyListWith + $ genArrayW8LargeHC (1024 * 10, 1024 * 64) + hspec $ do + describe "Idempotence" $ + it "resize" (resizeIdempotence defaultBlockConfig) + describe "Identity" $ do + propsChunk defaultBlockConfig + propsChunk2 defaultBlockConfig + propsSimple defaultBlockConfig + forM_ [-1, 5, 12, 100] + $ \i -> + forM_ [1, 512, 32 * 1024, 256 * 1024] + $ \bufsize -> do + propsBig defaultBlockConfig bufsize i large + describe "Highly compressible" + $ propsBig + defaultBlockConfig bufsize i largeHC + describe "setBlockMaxSize BlockMax256KB defaultBlockConfig" $ do + let config = setBlockMaxSize BlockMax256KB defaultBlockConfig + propsChunk config + propsChunk2 config + propsBig config 512 5 largeHC + describe "defaultBlockConfig" $ do + propsSimpleDecompressCompress defaultBlockConfig + propsBigDecompressCompress defaultBlockConfig 512 5 large + propsBigDecompressCompress defaultBlockConfig 512 5 largeHC + describe "setFrameEndMark True defaultFrameConfig" $ do + let ff = setFrameEndMark True defaultFrameConfig + propsFrame defaultBlockConfig ff 512 5 large + propsFrame defaultBlockConfig ff 512 5 largeHC + describe "setFrameEndMark True . setBlockMaxSize BlockMax256KB" + $ do + let bf = setBlockMaxSize BlockMax256KB defaultBlockConfig + ff = setFrameEndMark True defaultFrameConfig + propsFrame bf ff 512 5 large + propsFrame bf ff 512 5 largeHC + describe "parse config (decompressWith)" $ do + propsDecompressWithCompress 512 5 largeHC + + where + + propsSimpleDecompressCompress conf = do + it "decompress . compress == id" + $ property + $ forAll + ((,) <$> genAcceleration <*> genArrayW8List) + (monadicIO . liftIO . uncurry (decompressCompress conf 512)) + + propsBigDecompressCompress conf bufsize i l = do + it + ("decompress . compress (" + ++ show i ++ "/" ++ show bufsize ++ ") == id (big)") + $ decompressCompress conf bufsize i l + + propsDecompressWithCompress bufsize i l = do + it + "decompressWith . compress == id" + (decompressWithCompress bufsize i l) + + propsFrame bf ff bufsize i l = do + it ("decompressFrame . compressFrame (" ++ show i ++ ") == id") + $ decompressCompressFrame bf ff bufsize i l + + propsSimple conf = do + it "decompressResized . compress == id" + $ property + $ forAll + ((,) <$> genAcceleration <*> genArrayW8List) + (monadicIO . liftIO . uncurry (decompressResizedcompress conf)) + it "decompress . compress == id" + $ property + $ forAll + ((,) <$> genAcceleration <*> genArrayW8List) + (monadicIO . liftIO . uncurry (decompressCompress conf 512)) + + propsBig conf bufsize i l = do + it ("decompressResized . compress (" ++ show i ++ ") == id (big)") + $ decompressResizedcompress conf i l + it + ("decompress . compress (" + ++ show i ++ "/" ++ show bufsize ++ ") == id (big)") + $ decompressCompress conf bufsize i l + + propsChunk2 conf = do + it "decompressChunk . compressChunk (x2) == id (big)" + $ property + $ forAll + ((,,) + <$> genAcceleration + <*> genArrayW8Large + <*> genArrayW8Large) + (\(i, arr1, arr2) -> decompressCompressChunk2 conf i arr1 arr2) + + propsChunk conf = do + it "decompressChunk . compressChunk == id (big)" + $ property + $ forAll + ((,) <$> genAcceleration <*> genArrayW8Large) + (uncurry (decompressCompressChunk conf))