/*
* Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de>
*
* Redistribution and use in source and binary forms, with or without modifica-
* tion, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
* CIAL, 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 OTH-
* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License version 2 (the "GPL"), in which case the
* provisions of the GPL are applicable instead of the above. If you wish to
* allow the use of your version of this file only under the terms of the
* GPL and not to allow others to use your version of this file under the
* BSD license, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the GPL. If
* you do not delete the provisions above, a recipient may use your version
* of this file under either the BSD or the GPL.
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <getopt.h>
#include "lzf.h"
typedef unsigned char u8;
static void
usage (int ec)
{
fprintf (stderr, "\n"
"lzf, a very lightweight compression/decompression filter\n"
"written by Marc Lehmann <schmorp@schmorp.de> You can find more info at\n"
"http://liblzf.plan9.de/\n"
"\n"
"USAGE: lzf -c [-b blocksize] | -d\n"
" -c compress\n"
" -d decompress\n"
" -b specify the blocksize (default 64k-1)\n"
"\n"
);
exit (ec);
}
/*
* Anatomy: an lzf file consists of any number of blocks in the following format:
*
* "ZV\0" 2-byte-usize <uncompressed data>
* "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
* "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
*
*/
static void compress (unsigned int blocksize)
{
ssize_t us;
unsigned int cs;
u8 buff1[64*1024];
u8 buff2[64*1024];
u8 header[3+2+2];
header[0] = 'Z';
header[1] = 'V';
for(;;) {
us = fread (buff1, 1, blocksize, stdin);
if (us < blocksize)
{
if (us == 0)
break;
else if (!feof (stdin))
{
perror ("compress");
exit (1);
}
}
cs = lzf_compress (buff1, us, buff2, us - 4);
if (cs)
{
header[2] = 1;
header[3] = cs >> 8;
header[4] = cs & 0xff;
header[5] = us >> 8;
header[6] = us & 0xff;
fwrite (header, 3+2+2, 1, stdout);
fwrite (buff2, cs, 1, stdout);
}
else
{
header[2] = 0;
header[3] = us >> 8;
header[4] = us & 0xff;
fwrite (header, 3+2, 1, stdout);
fwrite (buff1, us, 1, stdout);
}
} while (!feof (stdin));
}
static void decompress (void)
{
ssize_t us;
unsigned int cs;
u8 buff1[64*1024];
u8 buff2[64*1024];
u8 header[3+2+2];
for(;;) {
if (fread (header, 3+2, 1, stdin) != 1)
{
if (feof (stdin))
break;
else
{
perror ("decompress");
exit (1);
}
}
if (header[0] != 'Z' || header[1] != 'V')
{
fprintf (stderr, "decompress: invalid stream - no magic number found\n");
exit (1);
}
cs = (header[3] << 8) | header[4];
if (header[2] == 1)
{
if (fread (header+3+2, 2, 1, stdin) != 1)
{
perror ("decompress");
exit (1);
}
us = (header[5] << 8) | header[6];
if (fread (buff1, cs, 1, stdin) != 1)
{
perror ("decompress");
exit (1);
}
if (lzf_decompress (buff1, cs, buff2, us) != us)
{
fprintf (stderr, "decompress: invalid stream - data corrupted\n");
exit (1);
}
fwrite (buff2, us, 1, stdout);
}
else if (header[2] == 0)
{
if (fread (buff2, cs, 1, stdin) != 1)
{
perror ("decompress");
exit (1);
}
fwrite (buff2, cs, 1, stdout);
}
else
{
fprintf (stderr, "decompress: invalid stream - unknown block type\n");
exit (1);
}
}
}
int
main (int argc, char *argv[])
{
int c;
unsigned int blocksize = 64*1024-1;
enum { m_compress, m_decompress } mode = m_compress;
while ((c = getopt (argc, argv, "cdb:h")) != -1)
switch (c)
{
case 'c':
mode = m_compress;
break;
case 'd':
mode = m_decompress;
break;
case 'b':
blocksize = atol (optarg);
break;
case 'h':
usage (0);
case ':':
fprintf (stderr, "required argument missing, use -h\n");
exit (1);
case '?':
fprintf (stderr, "unknown option, use -h\n");
exit (1);
default:
usage (1);
}
if (mode == m_compress)
compress (blocksize);
else if (mode == m_decompress)
decompress ();
else
abort ();
return 0;
}