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
10 //config:config BZIP2
11 //config: bool "bzip2"
12 //config: default y
13 //config: help
14 //config: bzip2 is a compression utility using the Burrows-Wheeler block
15 //config: sorting text compression algorithm, and Huffman coding. Compression
16 //config: is generally considerably better than that achieved by more
17 //config: conventional LZ77/LZ78-based compressors, and approaches the
18 //config: performance of the PPM family of statistical compressors.
19 //config:
20 //config: Unless you have a specific application which requires bzip2, you
21 //config: should probably say N here.
22
23 //applet:IF_BZIP2(APPLET(bzip2, BB_DIR_USR_BIN, BB_SUID_DROP))
24 //kbuild:lib-$(CONFIG_BZIP2) += bzip2.o
25
26 //usage:#define bzip2_trivial_usage
27 //usage: "[OPTIONS] [FILE]..."
28 //usage:#define bzip2_full_usage "\n\n"
29 //usage: "Compress FILEs (or stdin) with bzip2 algorithm\n"
30 //usage: "\n -1..9 Compression level"
31 //usage: "\n -d Decompress"
32 //usage: "\n -c Write to stdout"
33 //usage: "\n -f Force"
34
35 #include "libbb.h"
36 #include "bb_archive.h"
37
38 #define CONFIG_BZIP2_FAST 1
39
40 /* Speed test:
41 * Compiled with gcc 4.2.1, run on Athlon 64 1800 MHz (512K L2 cache).
42 * Stock bzip2 is 26.4% slower than bbox bzip2 at SPEED 1
43 * (time to compress gcc-4.2.1.tar is 126.4% compared to bbox).
44 * At SPEED 5 difference is 32.7%.
45 *
46 * Test run of all CONFIG_BZIP2_FAST values on a 11Mb text file:
47 * Size Time (3 runs)
48 * 0: 10828 4.145 4.146 4.148
49 * 1: 11097 3.845 3.860 3.861
50 * 2: 11392 3.763 3.767 3.768
51 * 3: 11892 3.722 3.724 3.727
52 * 4: 12740 3.637 3.640 3.644
53 * 5: 17273 3.497 3.509 3.509
54 */
55
56
57 #define BZ_DEBUG 0
58 /* Takes ~300 bytes, detects corruption caused by bad RAM etc */
59 #define BZ_LIGHT_DEBUG 0
60
61 #include "libarchive/bz/bzlib.h"
62
63 #include "libarchive/bz/bzlib_private.h"
64
65 #include "libarchive/bz/blocksort.c"
66 #include "libarchive/bz/bzlib.c"
67 #include "libarchive/bz/compress.c"
68 #include "libarchive/bz/huffman.c"
69
70 /* No point in being shy and having very small buffer here.
71 * bzip2 internal buffers are much bigger anyway, hundreds of kbytes.
72 * If iobuf is several pages long, malloc() may use mmap,
73 * making iobuf is page aligned and thus (maybe) have one memcpy less
74 * if kernel is clever enough.
75 */
76 enum {
77 IOBUF_SIZE = 8 * 1024
78 };
79
80 static uint8_t level;
81
82 /* NB: compressStream() has to return -1 on errors, not die.
83 * bbunpack() will correctly clean up in this case
84 * (delete incomplete .bz2 file)
85 */
86
87 /* Returns:
88 * -1 on errors
89 * total written bytes so far otherwise
90 */
91 static
IF_DESKTOP(long long)92 IF_DESKTOP(long long) int bz_write(bz_stream *strm, void* rbuf, ssize_t rlen, void *wbuf)
93 {
94 int n, n2, ret;
95
96 strm->avail_in = rlen;
97 strm->next_in = rbuf;
98 while (1) {
99 strm->avail_out = IOBUF_SIZE;
100 strm->next_out = wbuf;
101
102 ret = BZ2_bzCompress(strm, rlen ? BZ_RUN : BZ_FINISH);
103 if (ret != BZ_RUN_OK /* BZ_RUNning */
104 && ret != BZ_FINISH_OK /* BZ_FINISHing, but not done yet */
105 && ret != BZ_STREAM_END /* BZ_FINISHed */
106 ) {
107 bb_error_msg_and_die("internal error %d", ret);
108 }
109
110 n = IOBUF_SIZE - strm->avail_out;
111 if (n) {
112 n2 = full_write(STDOUT_FILENO, wbuf, n);
113 if (n2 != n) {
114 if (n2 >= 0)
115 errno = 0; /* prevent bogus error message */
116 bb_perror_msg(n2 >= 0 ? "short write" : bb_msg_write_error);
117 return -1;
118 }
119 }
120
121 if (ret == BZ_STREAM_END)
122 break;
123 if (rlen && strm->avail_in == 0)
124 break;
125 }
126 return 0 IF_DESKTOP( + strm->total_out );
127 }
128
129 static
IF_DESKTOP(long long)130 IF_DESKTOP(long long) int FAST_FUNC compressStream(transformer_state_t *xstate UNUSED_PARAM)
131 {
132 IF_DESKTOP(long long) int total;
133 ssize_t count;
134 bz_stream bzs; /* it's small */
135 #define strm (&bzs)
136 char *iobuf;
137 #define rbuf iobuf
138 #define wbuf (iobuf + IOBUF_SIZE)
139
140 iobuf = xmalloc(2 * IOBUF_SIZE);
141 BZ2_bzCompressInit(strm, level);
142
143 while (1) {
144 count = full_read(STDIN_FILENO, rbuf, IOBUF_SIZE);
145 if (count < 0) {
146 bb_perror_msg(bb_msg_read_error);
147 total = -1;
148 break;
149 }
150 /* if count == 0, bz_write finalizes compression */
151 total = bz_write(strm, rbuf, count, wbuf);
152 if (count == 0 || total < 0)
153 break;
154 }
155
156 /* Can't be conditional on ENABLE_FEATURE_CLEAN_UP -
157 * we are called repeatedly
158 */
159 BZ2_bzCompressEnd(strm);
160 free(iobuf);
161
162 return total;
163 }
164
165 int bzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
bzip2_main(int argc UNUSED_PARAM,char ** argv)166 int bzip2_main(int argc UNUSED_PARAM, char **argv)
167 {
168 unsigned opt;
169
170 /* standard bzip2 flags
171 * -d --decompress force decompression
172 * -z --compress force compression
173 * -k --keep keep (don't delete) input files
174 * -f --force overwrite existing output files
175 * -t --test test compressed file integrity
176 * -c --stdout output to standard out
177 * -q --quiet suppress noncritical error messages
178 * -v --verbose be verbose (a 2nd -v gives more)
179 * -s --small use less memory (at most 2500k)
180 * -1 .. -9 set block size to 100k .. 900k
181 * --fast alias for -1
182 * --best alias for -9
183 */
184
185 opt_complementary = "s2"; /* -s means -2 (compatibility) */
186 /* Must match bbunzip's constants OPT_STDOUT, OPT_FORCE! */
187 opt = getopt32(argv, "cfv" IF_BUNZIP2("dt") "123456789qzs");
188 #if ENABLE_BUNZIP2 /* bunzip2_main may not be visible... */
189 if (opt & 0x18) // -d and/or -t
190 return bunzip2_main(argc, argv);
191 opt >>= 5;
192 #else
193 opt >>= 3;
194 #endif
195 opt = (uint8_t)opt; /* isolate bits for -1..-8 */
196 opt |= 0x100; /* if nothing else, assume -9 */
197 level = 1;
198 while (!(opt & 1)) {
199 level++;
200 opt >>= 1;
201 }
202
203 argv += optind;
204 option_mask32 &= 0x7; /* ignore all except -cfv */
205 return bbunpack(argv, compressStream, append_ext, "bz2");
206 }
207