/* lzopack.c -- LZO example program: a simple file packer
This file is part of the LZO real-time data compression library.
Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer
All Rights Reserved.
The LZO library is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
The LZO library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with the LZO library; see the file COPYING.
If not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Markus F.X.J. Oberhumer
<markus@oberhumer.com>
http://www.oberhumer.com/opensource/lzo/
*/
/*************************************************************************
// NOTE: this is an example program, so do not use to backup your data.
//
// This program lacks things like sophisticated file handling but is
// pretty complete regarding compression - it should provide a good
// starting point for adaption for your applications.
//
// Please study LZO.FAQ and simple.c first.
**************************************************************************/
#include "lzo/lzoconf.h"
#include "lzo/lzo1x.h"
/* portability layer */
static const char *progname = NULL;
#define WANT_LZO_MALLOC 1
#define WANT_LZO_FREAD 1
#define WANT_LZO_WILDARGV 1
#define WANT_XMALLOC 1
#include "examples/portab.h"
static unsigned long total_in = 0;
static unsigned long total_out = 0;
static lzo_bool opt_debug = 0;
/* magic file header for lzopack-compressed files */
static const unsigned char magic[7] =
{ 0x00, 0xe9, 0x4c, 0x5a, 0x4f, 0xff, 0x1a };
/*************************************************************************
// file IO
**************************************************************************/
static lzo_uint xread(FILE *fp, lzo_voidp buf, lzo_uint len, lzo_bool allow_eof)
{
lzo_uint l;
l = (lzo_uint) lzo_fread(fp, buf, len);
if (l > len)
{
fprintf(stderr, "\n%s: internal error - something is wrong with your C library !!!\n", progname);
exit(1);
}
if (l != len && !allow_eof)
{
fprintf(stderr, "\n%s: read error - premature end of file\n", progname);
exit(1);
}
total_in += (unsigned long) l;
return l;
}
static lzo_uint xwrite(FILE *fp, const lzo_voidp buf, lzo_uint len)
{
if (fp != NULL && lzo_fwrite(fp, buf, len) != len)
{
fprintf(stderr, "\n%s: write error (disk full ?)\n", progname);
exit(1);
}
total_out += (unsigned long) len;
return len;
}
static int xgetc(FILE *fp)
{
unsigned char c;
xread(fp, (lzo_voidp) &c, 1, 0);
return c;
}
static void xputc(FILE *fp, int c)
{
unsigned char cc = (unsigned char) (c & 0xff);
xwrite(fp, (const lzo_voidp) &cc, 1);
}
/* read and write portable 32-bit integers */
static lzo_uint32_t xread32(FILE *fp)
{
unsigned char b[4];
lzo_uint32_t v;
xread(fp, b, 4, 0);
v = (lzo_uint32_t) b[3] << 0;
v |= (lzo_uint32_t) b[2] << 8;
v |= (lzo_uint32_t) b[1] << 16;
v |= (lzo_uint32_t) b[0] << 24;
return v;
}
static void xwrite32(FILE *fp, lzo_uint v)
{
unsigned char b[4];
b[3] = (unsigned char) ((v >> 0) & 0xff);
b[2] = (unsigned char) ((v >> 8) & 0xff);
b[1] = (unsigned char) ((v >> 16) & 0xff);
b[0] = (unsigned char) ((v >> 24) & 0xff);
xwrite(fp, b, 4);
}
/*************************************************************************
// compress
//
// possible improvement: we could use overlapping compression to
// save some memory - see overlap.c. This would require some minor
// changes in the decompression code as well, because if a block
// turns out to be incompressible we would still have to store it in its
// "compressed" (i.e. then slightly enlarged) form because the original
// (uncompressed) data would have been lost during the overlapping
// compression.
**************************************************************************/
static int do_compress(FILE *fi, FILE *fo, int compression_level, lzo_uint block_size)
{
int r = 0;
lzo_bytep in = NULL;
lzo_bytep out = NULL;
lzo_voidp wrkmem = NULL;
lzo_uint in_len;
lzo_uint out_len;
lzo_uint wrkmem_size;
lzo_uint32_t flags = 1; /* do compute a checksum */
int method = 1; /* compression method: LZO1X */
lzo_uint32_t checksum;
total_in = total_out = 0;
/*
* Step 1: write magic header, flags & block size, init checksum
*/
xwrite(fo, magic, sizeof(magic));
xwrite32(fo, flags);
xputc(fo, method); /* compression method */
xputc(fo, compression_level); /* compression level */
xwrite32(fo, block_size);
checksum = lzo_adler32(0, NULL, 0);
/*
* Step 2: allocate compression buffers and work-memory
*/
in = (lzo_bytep) xmalloc(block_size);
out = (lzo_bytep) xmalloc(block_size + block_size / 16 + 64 + 3);
if (compression_level == 9)
wrkmem_size = LZO1X_999_MEM_COMPRESS;
else
wrkmem_size = LZO1X_1_MEM_COMPRESS;
wrkmem = (lzo_voidp) xmalloc(wrkmem_size);
if (in == NULL || out == NULL || wrkmem == NULL)
{
printf("%s: out of memory\n", progname);
r = 1;
goto err;
}
/*
* Step 3: process blocks
*/
for (;;)
{
/* read block */
in_len = xread(fi, in, block_size, 1);
if (in_len == 0)
break;
/* update checksum */
if (flags & 1)
checksum = lzo_adler32(checksum, in, in_len);
/* clear wrkmem (not needed, only for debug/benchmark purposes) */
if (opt_debug)
lzo_memset(wrkmem, 0xff, wrkmem_size);
/* compress block */
if (compression_level == 9)
r = lzo1x_999_compress(in, in_len, out, &out_len, wrkmem);
else
r = lzo1x_1_compress(in, in_len, out, &out_len, wrkmem);
if (r != LZO_E_OK || out_len > in_len + in_len / 16 + 64 + 3)
{
/* this should NEVER happen */
printf("internal error - compression failed: %d\n", r);
r = 2;
goto err;
}
/* write uncompressed block size */
xwrite32(fo, in_len);
if (out_len < in_len)
{
/* write compressed block */
xwrite32(fo, out_len);
xwrite(fo, out, out_len);
}
else
{
/* not compressible - write uncompressed block */
xwrite32(fo, in_len);
xwrite(fo, in, in_len);
}
}
/* write EOF marker */
xwrite32(fo, 0);
/* write checksum */
if (flags & 1)
xwrite32(fo, checksum);
r = 0;
err:
lzo_free(wrkmem);
lzo_free(out);
lzo_free(in);
return r;
}
/*************************************************************************
// decompress / test
//
// We are using overlapping (in-place) decompression to save some
// memory - see overlap.c.
**************************************************************************/
static int do_decompress(FILE *fi, FILE *fo)
{
int r = 0;
lzo_bytep buf = NULL;
lzo_uint buf_len;
unsigned char m [ sizeof(magic) ];
lzo_uint32_t flags;
int method;
int compression_level;
lzo_uint block_size;
lzo_uint32_t checksum;
total_in = total_out = 0;
/*
* Step 1: check magic header, read flags & block size, init checksum
*/
if (xread(fi, m, sizeof(magic), 1) != sizeof(magic) ||
memcmp(m, magic, sizeof(magic)) != 0)
{
printf("%s: header error - this file is not compressed by lzopack\n", progname);
r = 1;
goto err;
}
flags = xread32(fi);
method = xgetc(fi);
compression_level = xgetc(fi);
if (method != 1)
{
printf("%s: header error - invalid method %d (level %d)\n",
progname, method, compression_level);
r = 2;
goto err;
}
block_size = xread32(fi);
if (block_size < 1024 || block_size > 8L * 1024L * 1024L)
{
printf("%s: header error - invalid block size %ld\n",
progname, (long) block_size);
r = 3;
goto err;
}
checksum = lzo_adler32(0, NULL, 0);
/*
* Step 2: allocate buffer for in-place decompression
*/
buf_len = block_size + block_size / 16 + 64 + 3;
buf = (lzo_bytep) xmalloc(buf_len);
if (buf == NULL)
{
printf("%s: out of memory\n", progname);
r = 4;
goto err;
}
/*
* Step 3: process blocks
*/
for (;;)
{
lzo_bytep in;
lzo_bytep out;
lzo_uint in_len;
lzo_uint out_len;
/* read uncompressed size */
out_len = xread32(fi);
/* exit if last block (EOF marker) */
if (out_len == 0)
break;
/* read compressed size */
in_len = xread32(fi);
/* sanity check of the size values */
if (in_len > block_size || out_len > block_size ||
in_len == 0 || in_len > out_len)
{
printf("%s: block size error - data corrupted\n", progname);
r = 5;
goto err;
}
/* place compressed block at the top of the buffer */
in = buf + buf_len - in_len;
out = buf;
/* read compressed block data */
xread(fi, in, in_len, 0);
if (in_len < out_len)
{
/* decompress - use safe decompressor as data might be corrupted
* during a file transfer */
lzo_uint new_len = out_len;
r = lzo1x_decompress_safe(in, in_len, out, &new_len, NULL);
if (r != LZO_E_OK || new_len != out_len)
{
printf("%s: compressed data violation\n", progname);
r = 6;
goto err;
}
/* write decompressed block */
xwrite(fo, out, out_len);
/* update checksum */
if (flags & 1)
checksum = lzo_adler32(checksum, out, out_len);
}
else
{
/* write original (incompressible) block */
xwrite(fo, in, in_len);
/* update checksum */
if (flags & 1)
checksum = lzo_adler32(checksum, in, in_len);
}
}
/* read and verify checksum */
if (flags & 1)
{
lzo_uint32_t c = xread32(fi);
if (c != checksum)
{
printf("%s: checksum error - data corrupted\n", progname);
r = 7;
goto err;
}
}
r = 0;
err:
lzo_free(buf);
return r;
}
/*************************************************************************
//
**************************************************************************/
static void usage(void)
{
printf("usage: %s [-9] input-file output-file (compress)\n", progname);
printf("usage: %s -d input-file output-file (decompress)\n", progname);
printf("usage: %s -t input-file... (test)\n", progname);
exit(1);
}
/* open input file */
static FILE *xopen_fi(const char *name)
{
FILE *fp;
fp = fopen(name, "rb");
if (fp == NULL)
{
printf("%s: cannot open input file %s\n", progname, name);
exit(1);
}
#if defined(HAVE_STAT) && defined(S_ISREG)
{
struct stat st;
int is_regular = 1;
if (stat(name, &st) != 0 || !S_ISREG(st.st_mode))
is_regular = 0;
if (!is_regular)
{
printf("%s: %s is not a regular file\n", progname, name);
fclose(fp); fp = NULL;
exit(1);
}
}
#endif
return fp;
}
/* open output file */
static FILE *xopen_fo(const char *name)
{
FILE *fp;
#if 0
/* this is an example program, so make sure we don't overwrite a file */
fp = fopen(name, "rb");
if (fp != NULL)
{
printf("%s: file %s already exists -- not overwritten\n", progname, name);
fclose(fp); fp = NULL;
exit(1);
}
#endif
fp = fopen(name, "wb");
if (fp == NULL)
{
printf("%s: cannot open output file %s\n", progname, name);
exit(1);
}
return fp;
}
/* close file */
static void xclose(FILE *fp)
{
if (fp)
{
int err;
err = ferror(fp);
if (fclose(fp) != 0)
err = 1;
if (err)
{
printf("%s: error while closing file\n", progname);
exit(1);
}
}
}
/*************************************************************************
//
**************************************************************************/
int __lzo_cdecl_main main(int argc, char *argv[])
{
int i = 1;
int r = 0;
FILE *fi = NULL;
FILE *fo = NULL;
const char *in_name = NULL;
const char *out_name = NULL;
unsigned opt_decompress = 0;
unsigned opt_test = 0;
int opt_compression_level = 1;
lzo_uint opt_block_size;
const char *s;
lzo_wildargv(&argc, &argv);
progname = argv[0];
for (s = progname; *s; s++)
if ((*s == '/' || *s == '\\') && s[1])
progname = s + 1;
printf("\nLZO real-time data compression library (v%s, %s).\n",
lzo_version_string(), lzo_version_date());
printf("Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer\nAll Rights Reserved.\n\n");
#if 0
printf(
"*** DISCLAIMER ***\n"
" This is an example program, do not use to backup your data !\n"
" Get LZOP if you're interested into a full-featured packer.\n"
" See http://www.oberhumer.com/opensource/lzop/\n"
"\n");
#endif
/*
* Step 1: initialize the LZO library
*/
if (lzo_init() != LZO_E_OK)
{
printf("internal error - lzo_init() failed !!!\n");
printf("(this usually indicates a compiler bug - try recompiling\nwithout optimizations, and enable '-DLZO_DEBUG' for diagnostics)\n");
exit(1);
}
/*
* Step 2: setup memory
*/
opt_block_size = 256 * 1024L;
#if defined(LZO_MM_AHSHIFT)
/* reduce memory requirements for ancient 16-bit DOS 640kB real-mode */
if (LZO_MM_AHSHIFT != 3)
opt_block_size = 16 * 1024L;
#endif
/*
* Step 3: get options
*/
while (i < argc && argv[i][0] == '-')
{
if (strcmp(argv[i],"-d") == 0)
opt_decompress = 1;
else if (strcmp(argv[i],"-t") == 0)
opt_test = 1;
else if (strcmp(argv[i],"-9") == 0)
opt_compression_level = 9;
else if (argv[i][1] == 'b' && argv[i][2])
{
long b = atol(&argv[i][2]);
if (b >= 1024L && b <= 8*1024*1024L)
opt_block_size = (lzo_uint) b;
else
{
printf("%s: invalid block_size in option '%s'.\n", progname, argv[i]);
usage();
}
}
else if (strcmp(argv[i],"--debug") == 0)
opt_debug += 1;
else
usage();
i++;
}
if (opt_test && i >= argc)
usage();
if (!opt_test && i + 2 != argc)
usage();
/*
* Step 4: process file(s)
*/
if (opt_test)
{
while (i < argc && r == 0)
{
in_name = argv[i++];
fi = xopen_fi(in_name);
r = do_decompress(fi, NULL);
if (r == 0)
printf("%s: %s tested ok (%lu -> %lu bytes)\n",
progname, in_name, total_in, total_out);
xclose(fi); fi = NULL;
}
}
else if (opt_decompress)
{
in_name = argv[i++];
out_name = argv[i++];
fi = xopen_fi(in_name);
fo = xopen_fo(out_name);
r = do_decompress(fi, fo);
if (r == 0)
printf("%s: decompressed %lu into %lu bytes\n",
progname, total_in, total_out);
}
else /* compress */
{
in_name = argv[i++];
out_name = argv[i++];
fi = xopen_fi(in_name);
fo = xopen_fo(out_name);
r = do_compress(fi, fo, opt_compression_level, opt_block_size);
if (r == 0)
printf("%s: compressed %lu into %lu bytes\n",
progname, total_in, total_out);
}
xclose(fi); fi = NULL;
xclose(fo); fo = NULL;
return r;
}
/* vim:set ts=4 sw=4 et: */