hush/archival/bzip2.c

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/*
* Copyright (C) 2007 Denys Vlasenko <vda.linux@googlemail.com>
*
* This file uses bzip2 library code which is written
* by Julian Seward <jseward@bzip.org>.
* See README and LICENSE files in bz/ directory for more information
* about bzip2 library code.
*/
#include "libbb.h"
#define CONFIG_BZIP2_FEATURE_SPEED 1
/* Speed test:
* Compiled with gcc 4.2.1, run on Athlon 64 1800 MHz (512K L2 cache).
* Stock bzip2 is 26.4% slower than bbox bzip2 at SPEED 1
* (time to compress gcc-4.2.1.tar is 126.4% compared to bbox).
* At SPEED 5 difference is 32.7%.
*
* Test run of all CONFIG_BZIP2_FEATURE_SPEED values on a 11Mb text file:
* Size Time (3 runs)
* 0: 10828 4.145 4.146 4.148
* 1: 11097 3.845 3.860 3.861
* 2: 11392 3.763 3.767 3.768
* 3: 11892 3.722 3.724 3.727
* 4: 12740 3.637 3.640 3.644
* 5: 17273 3.497 3.509 3.509
*/
#define BZ_DEBUG 0
/* Takes ~300 bytes, detects corruption caused by bad RAM etc */
#define BZ_LIGHT_DEBUG 0
#include "bz/bzlib.h"
#include "bz/bzlib_private.h"
#include "bz/blocksort.c"
#include "bz/bzlib.c"
#include "bz/compress.c"
#include "bz/huffman.c"
/* No point in being shy and having very small buffer here.
* bzip2 internal buffers are much bigger anyway, hundreds of kbytes.
* If iobuf is several pages long, malloc() may use mmap,
* making iobuf is page aligned and thus (maybe) have one memcpy less
* if kernel is clever enough.
*/
enum {
IOBUF_SIZE = 8 * 1024
};
static uint8_t level;
/* NB: compressStream() has to return -1 on errors, not die.
* bbunpack() will correctly clean up in this case
* (delete incomplete .bz2 file)
*/
/* Returns:
* -1 on errors
* total written bytes so far otherwise
*/
static
USE_DESKTOP(long long) int bz_write(bz_stream *strm, void* rbuf, ssize_t rlen, void *wbuf)
{
int n, n2, ret;
strm->avail_in = rlen;
strm->next_in = rbuf;
while (1) {
strm->avail_out = IOBUF_SIZE;
strm->next_out = wbuf;
ret = BZ2_bzCompress(strm, rlen ? BZ_RUN : BZ_FINISH);
if (ret != BZ_RUN_OK /* BZ_RUNning */
&& ret != BZ_FINISH_OK /* BZ_FINISHing, but not done yet */
&& ret != BZ_STREAM_END /* BZ_FINISHed */
) {
bb_error_msg_and_die("internal error %d", ret);
}
n = IOBUF_SIZE - strm->avail_out;
if (n) {
n2 = full_write(STDOUT_FILENO, wbuf, n);
if (n2 != n) {
if (n2 >= 0)
errno = 0; /* prevent bogus error message */
bb_perror_msg(n2 >= 0 ? "short write" : "write error");
return -1;
}
}
if (ret == BZ_STREAM_END)
break;
if (rlen && strm->avail_in == 0)
break;
}
return 0 USE_DESKTOP( + strm->total_out );
}
static
USE_DESKTOP(long long) int compressStream(void)
{
USE_DESKTOP(long long) int total;
ssize_t count;
bz_stream bzs; /* it's small */
#define strm (&bzs)
char *iobuf;
#define rbuf iobuf
#define wbuf (iobuf + IOBUF_SIZE)
iobuf = xmalloc(2 * IOBUF_SIZE);
BZ2_bzCompressInit(strm, level);
while (1) {
count = full_read(STDIN_FILENO, rbuf, IOBUF_SIZE);
if (count < 0) {
bb_perror_msg("read error");
total = -1;
break;
}
/* if count == 0, bz_write finalizes compression */
total = bz_write(strm, rbuf, count, wbuf);
if (count == 0 || total < 0)
break;
}
#if ENABLE_FEATURE_CLEAN_UP
BZ2_bzCompressEnd(strm);
free(iobuf);
#endif
return total;
}
static
char* make_new_name_bzip2(char *filename)
{
return xasprintf("%s.bz2", filename);
}
int bzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int bzip2_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opt;
/* standard bzip2 flags
* -d --decompress force decompression
* -z --compress force compression
* -k --keep keep (don't delete) input files
* -f --force overwrite existing output files
* -t --test test compressed file integrity
* -c --stdout output to standard out
* -q --quiet suppress noncritical error messages
* -v --verbose be verbose (a 2nd -v gives more)
* -s --small use less memory (at most 2500k)
* -1 .. -9 set block size to 100k .. 900k
* --fast alias for -1
* --best alias for -9
*/
opt_complementary = "s2"; /* -s means -2 (compatibility) */
/* Must match bbunzip's constants OPT_STDOUT, OPT_FORCE! */
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opt = getopt32(argv, "cfv" USE_BUNZIP2("dt") "123456789qzs");
#if ENABLE_BUNZIP2 /* bunzip2_main may not be visible... */
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if (opt & 0x18) // -d and/or -t
return bunzip2_main(argc, argv);
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opt >>= 5;
#else
opt >>= 3;
#endif
opt = (uint8_t)opt; /* isolate bits for -1..-8 */
opt |= 0x100; /* if nothing else, assume -9 */
level = 1;
while (!(opt & 1)) {
level++;
opt >>= 1;
}
argv += optind;
option_mask32 &= 0x7; /* ignore all except -cfv */
return bbunpack(argv, make_new_name_bzip2, compressStream);
}