1/* 2 * Copyright (C) 2007 Denys Vlasenko <vda.linux@googlemail.com> 3 * 4 * This file uses bzip2 library code which is written 5 * by Julian Seward <jseward@bzip.org>. 6 * See README and LICENSE files in bz/ directory for more information 7 * about bzip2 library code. 8 */ 9//config:config BZIP2 10//config: bool "bzip2 (16 kb)" 11//config: default y 12//config: help 13//config: bzip2 is a compression utility using the Burrows-Wheeler block 14//config: sorting text compression algorithm, and Huffman coding. Compression 15//config: is generally considerably better than that achieved by more 16//config: conventional LZ77/LZ78-based compressors, and approaches the 17//config: performance of the PPM family of statistical compressors. 18//config: 19//config: Unless you have a specific application which requires bzip2, you 20//config: should probably say N here. 21//config: 22//config:config BZIP2_SMALL 23//config: int "Trade bytes for speed (0:fast, 9:small)" 24//config: default 8 # all "fast or small" options default to small 25//config: range 0 9 26//config: depends on BZIP2 27//config: help 28//config: Trade code size versus speed. 29//config: Approximate values with gcc-6.3.0 "bzip -9" compressing 30//config: linux-4.15.tar were: 31//config: value time (sec) code size (386) 32//config: 9 (smallest) 70.11 7687 33//config: 8 67.93 8091 34//config: 7 67.88 8405 35//config: 6 67.78 8624 36//config: 5 67.05 9427 37//config: 4-0 (fastest) 64.14 12083 38//config: 39//config:config FEATURE_BZIP2_DECOMPRESS 40//config: bool "Enable decompression" 41//config: default y 42//config: depends on BZIP2 || BUNZIP2 || BZCAT 43//config: help 44//config: Enable -d (--decompress) and -t (--test) options for bzip2. 45//config: This will be automatically selected if bunzip2 or bzcat is 46//config: enabled. 47 48//applet:IF_BZIP2(APPLET(bzip2, BB_DIR_USR_BIN, BB_SUID_DROP)) 49 50//kbuild:lib-$(CONFIG_BZIP2) += bzip2.o 51 52//usage:#define bzip2_trivial_usage 53//usage: "[-cfk" IF_FEATURE_BZIP2_DECOMPRESS("dt") "123456789] [FILE]..." 54//usage:#define bzip2_full_usage "\n\n" 55//usage: "Compress FILEs (or stdin) with bzip2 algorithm\n" 56//usage: "\n -1..9 Compression level" 57//usage: IF_FEATURE_BZIP2_DECOMPRESS( 58//usage: "\n -d Decompress" 59//usage: ) 60//usage: "\n -c Write to stdout" 61//usage: "\n -f Force" 62//usage: "\n -k Keep input files" 63//usage: IF_FEATURE_BZIP2_DECOMPRESS( 64//usage: "\n -t Test integrity" 65//usage: ) 66 67#include "libbb.h" 68#include "bb_archive.h" 69 70#if CONFIG_BZIP2_SMALL >= 4 71#define BZIP2_SPEED (9 - CONFIG_BZIP2_SMALL) 72#else 73#define BZIP2_SPEED 5 74#endif 75 76/* Speed test: 77 * Compiled with gcc 4.2.1, run on Athlon 64 1800 MHz (512K L2 cache). 78 * Stock bzip2 is 26.4% slower than bbox bzip2 at SPEED 1 79 * (time to compress gcc-4.2.1.tar is 126.4% compared to bbox). 80 * At SPEED 5 difference is 32.7%. 81 * 82 * Test run of all BZIP2_SPEED values on a 11Mb text file: 83 * Size Time (3 runs) 84 * 0: 10828 4.145 4.146 4.148 85 * 1: 11097 3.845 3.860 3.861 86 * 2: 11392 3.763 3.767 3.768 87 * 3: 11892 3.722 3.724 3.727 88 * 4: 12740 3.637 3.640 3.644 89 * 5: 17273 3.497 3.509 3.509 90 */ 91 92 93#define BZ_DEBUG 0 94/* Takes ~300 bytes, detects corruption caused by bad RAM etc */ 95#define BZ_LIGHT_DEBUG 0 96 97#include "libarchive/bz/bzlib.h" 98 99#include "libarchive/bz/bzlib_private.h" 100 101#include "libarchive/bz/blocksort.c" 102#include "libarchive/bz/bzlib.c" 103#include "libarchive/bz/compress.c" 104#include "libarchive/bz/huffman.c" 105 106/* No point in being shy and having very small buffer here. 107 * bzip2 internal buffers are much bigger anyway, hundreds of kbytes. 108 * If iobuf is several pages long, malloc() may use mmap, 109 * making iobuf page aligned and thus (maybe) have one memcpy less 110 * if kernel is clever enough. 111 */ 112enum { 113 IOBUF_SIZE = 8 * 1024 114}; 115 116/* NB: compressStream() has to return -1 on errors, not die. 117 * bbunpack() will correctly clean up in this case 118 * (delete incomplete .bz2 file) 119 */ 120 121/* Returns: 122 * -1 on errors 123 * total written bytes so far otherwise 124 */ 125static 126IF_DESKTOP(long long) int bz_write(bz_stream *strm, void* rbuf, ssize_t rlen, void *wbuf) 127{ 128 int n, n2, ret; 129 130 strm->avail_in = rlen; 131 strm->next_in = rbuf; 132 while (1) { 133 strm->avail_out = IOBUF_SIZE; 134 strm->next_out = wbuf; 135 136 ret = BZ2_bzCompress(strm, rlen ? BZ_RUN : BZ_FINISH); 137 if (ret != BZ_RUN_OK /* BZ_RUNning */ 138 && ret != BZ_FINISH_OK /* BZ_FINISHing, but not done yet */ 139 && ret != BZ_STREAM_END /* BZ_FINISHed */ 140 ) { 141 bb_error_msg_and_die("internal error %d", ret); 142 } 143 144 n = IOBUF_SIZE - strm->avail_out; 145 if (n) { 146 n2 = full_write(STDOUT_FILENO, wbuf, n); 147 if (n2 != n) { 148 if (n2 >= 0) 149 errno = 0; /* prevent bogus error message */ 150 bb_simple_perror_msg(n2 >= 0 ? "short write" : bb_msg_write_error); 151 return -1; 152 } 153 } 154 155 if (ret == BZ_STREAM_END) 156 break; 157 if (rlen && strm->avail_in == 0) 158 break; 159 } 160 return 0 IF_DESKTOP( + strm->total_out ); 161} 162 163static 164IF_DESKTOP(long long) int FAST_FUNC compressStream(transformer_state_t *xstate UNUSED_PARAM) 165{ 166 IF_DESKTOP(long long) int total; 167 unsigned opt, level; 168 ssize_t count; 169 bz_stream bzs; /* it's small */ 170#define strm (&bzs) 171 char *iobuf; 172#define rbuf iobuf 173#define wbuf (iobuf + IOBUF_SIZE) 174 175 iobuf = xmalloc(2 * IOBUF_SIZE); 176 177 opt = option_mask32 >> (BBUNPK_OPTSTRLEN IF_FEATURE_BZIP2_DECOMPRESS(+ 2) + 2); 178 /* skipped BBUNPK_OPTSTR, "dt" and "zs" bits */ 179 opt |= 0x100; /* if nothing else, assume -9 */ 180 level = 0; 181 for (;;) { 182 level++; 183 if (opt & 1) break; 184 opt >>= 1; 185 } 186 187 BZ2_bzCompressInit(strm, level); 188 189 while (1) { 190 count = full_read(STDIN_FILENO, rbuf, IOBUF_SIZE); 191 if (count < 0) { 192 bb_simple_perror_msg(bb_msg_read_error); 193 total = -1; 194 break; 195 } 196 /* if count == 0, bz_write finalizes compression */ 197 total = bz_write(strm, rbuf, count, wbuf); 198 if (count == 0 || total < 0) 199 break; 200 } 201 202 /* Can't be conditional on ENABLE_FEATURE_CLEAN_UP - 203 * we are called repeatedly 204 */ 205 BZ2_bzCompressEnd(strm); 206 free(iobuf); 207 208 return total; 209} 210 211int bzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 212int bzip2_main(int argc UNUSED_PARAM, char **argv) 213{ 214 unsigned opt; 215 216 /* standard bzip2 flags 217 * -d --decompress force decompression 218 * -z --compress force compression 219 * -k --keep keep (don't delete) input files 220 * -f --force overwrite existing output files 221 * -t --test test compressed file integrity 222 * -c --stdout output to standard out 223 * -q --quiet suppress noncritical error messages 224 * -v --verbose be verbose (a 2nd -v gives more) 225 * -s --small use less memory (at most 2500k) 226 * -1 .. -9 set block size to 100k .. 900k 227 * --fast alias for -1 228 * --best alias for -9 229 */ 230 231 opt = getopt32(argv, "^" 232 /* Must match BBUNPK_foo constants! */ 233 BBUNPK_OPTSTR IF_FEATURE_BZIP2_DECOMPRESS("dt") "zs123456789" 234 "\0" "s2" /* -s means -2 (compatibility) */ 235 ); 236#if ENABLE_FEATURE_BZIP2_DECOMPRESS /* bunzip2_main may not be visible... */ 237 if (opt & (BBUNPK_OPT_DECOMPRESS|BBUNPK_OPT_TEST)) /* -d and/or -t */ 238 return bunzip2_main(argc, argv); 239#else 240 /* clear "decompress" and "test" bits (or bbunpack() can get confused) */ 241 /* in !BZIP2_DECOMPRESS config, these bits are -zs and are unused */ 242 option_mask32 = opt & ~(BBUNPK_OPT_DECOMPRESS|BBUNPK_OPT_TEST); 243#endif 244 245 argv += optind; 246 return bbunpack(argv, compressStream, append_ext, "bz2"); 247} 248