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5ca28f79 | 1 | /* gun.c -- simple gunzip to give an example of the use of inflateBack() |
da09a436 | 2 | * Copyright (C) 2003, 2005, 2008, 2010, 2012 Mark Adler |
5ca28f79 | 3 | * For conditions of distribution and use, see copyright notice in zlib.h |
da09a436 | 4 | Version 1.7 12 August 2012 Mark Adler */ |
5ca28f79 L |
5 | |
6 | /* Version history: | |
7 | 1.0 16 Feb 2003 First version for testing of inflateBack() | |
8 | 1.1 21 Feb 2005 Decompress concatenated gzip streams | |
9 | Remove use of "this" variable (C++ keyword) | |
10 | Fix return value for in() | |
11 | Improve allocation failure checking | |
12 | Add typecasting for void * structures | |
13 | Add -h option for command version and usage | |
14 | Add a bunch of comments | |
15 | 1.2 20 Mar 2005 Add Unix compress (LZW) decompression | |
16 | Copy file attributes from input file to output file | |
17 | 1.3 12 Jun 2005 Add casts for error messages [Oberhumer] | |
18 | 1.4 8 Dec 2006 LZW decompression speed improvements | |
19 | 1.5 9 Feb 2008 Avoid warning in latest version of gcc | |
20 | 1.6 17 Jan 2010 Avoid signed/unsigned comparison warnings | |
da09a436 | 21 | 1.7 12 Aug 2012 Update for z_const usage in zlib 1.2.8 |
5ca28f79 L |
22 | */ |
23 | ||
24 | /* | |
25 | gun [ -t ] [ name ... ] | |
26 | ||
27 | decompresses the data in the named gzip files. If no arguments are given, | |
28 | gun will decompress from stdin to stdout. The names must end in .gz, -gz, | |
29 | .z, -z, _z, or .Z. The uncompressed data will be written to a file name | |
30 | with the suffix stripped. On success, the original file is deleted. On | |
31 | failure, the output file is deleted. For most failures, the command will | |
32 | continue to process the remaining names on the command line. A memory | |
33 | allocation failure will abort the command. If -t is specified, then the | |
34 | listed files or stdin will be tested as gzip files for integrity (without | |
35 | checking for a proper suffix), no output will be written, and no files | |
36 | will be deleted. | |
37 | ||
38 | Like gzip, gun allows concatenated gzip streams and will decompress them, | |
39 | writing all of the uncompressed data to the output. Unlike gzip, gun allows | |
40 | an empty file on input, and will produce no error writing an empty output | |
41 | file. | |
42 | ||
43 | gun will also decompress files made by Unix compress, which uses LZW | |
44 | compression. These files are automatically detected by virtue of their | |
45 | magic header bytes. Since the end of Unix compress stream is marked by the | |
46 | end-of-file, they cannot be concantenated. If a Unix compress stream is | |
47 | encountered in an input file, it is the last stream in that file. | |
48 | ||
de1ab01e | 49 | Like gunzip and uncompress, the file attributes of the original compressed |
5ca28f79 L |
50 | file are maintained in the final uncompressed file, to the extent that the |
51 | user permissions allow it. | |
52 | ||
53 | On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version | |
54 | 1.2.4) is on the same file, when gun is linked with zlib 1.2.2. Also the | |
55 | LZW decompression provided by gun is about twice as fast as the standard | |
56 | Unix uncompress command. | |
57 | */ | |
58 | ||
59 | /* external functions and related types and constants */ | |
60 | #include <stdio.h> /* fprintf() */ | |
61 | #include <stdlib.h> /* malloc(), free() */ | |
62 | #include <string.h> /* strerror(), strcmp(), strlen(), memcpy() */ | |
63 | #include <errno.h> /* errno */ | |
64 | #include <fcntl.h> /* open() */ | |
65 | #include <unistd.h> /* read(), write(), close(), chown(), unlink() */ | |
66 | #include <sys/types.h> | |
67 | #include <sys/stat.h> /* stat(), chmod() */ | |
68 | #include <utime.h> /* utime() */ | |
69 | #include "zlib.h" /* inflateBackInit(), inflateBack(), */ | |
70 | /* inflateBackEnd(), crc32() */ | |
71 | ||
72 | /* function declaration */ | |
73 | #define local static | |
74 | ||
75 | /* buffer constants */ | |
76 | #define SIZE 32768U /* input and output buffer sizes */ | |
77 | #define PIECE 16384 /* limits i/o chunks for 16-bit int case */ | |
78 | ||
79 | /* structure for infback() to pass to input function in() -- it maintains the | |
80 | input file and a buffer of size SIZE */ | |
81 | struct ind { | |
82 | int infile; | |
83 | unsigned char *inbuf; | |
84 | }; | |
85 | ||
86 | /* Load input buffer, assumed to be empty, and return bytes loaded and a | |
87 | pointer to them. read() is called until the buffer is full, or until it | |
88 | returns end-of-file or error. Return 0 on error. */ | |
da09a436 | 89 | local unsigned in(void *in_desc, z_const unsigned char **buf) |
5ca28f79 L |
90 | { |
91 | int ret; | |
92 | unsigned len; | |
93 | unsigned char *next; | |
94 | struct ind *me = (struct ind *)in_desc; | |
95 | ||
96 | next = me->inbuf; | |
97 | *buf = next; | |
98 | len = 0; | |
99 | do { | |
100 | ret = PIECE; | |
101 | if ((unsigned)ret > SIZE - len) | |
102 | ret = (int)(SIZE - len); | |
103 | ret = (int)read(me->infile, next, ret); | |
104 | if (ret == -1) { | |
105 | len = 0; | |
106 | break; | |
107 | } | |
108 | next += ret; | |
109 | len += ret; | |
110 | } while (ret != 0 && len < SIZE); | |
111 | return len; | |
112 | } | |
113 | ||
114 | /* structure for infback() to pass to output function out() -- it maintains the | |
115 | output file, a running CRC-32 check on the output and the total number of | |
116 | bytes output, both for checking against the gzip trailer. (The length in | |
117 | the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and | |
118 | the output is greater than 4 GB.) */ | |
119 | struct outd { | |
120 | int outfile; | |
121 | int check; /* true if checking crc and total */ | |
122 | unsigned long crc; | |
123 | unsigned long total; | |
124 | }; | |
125 | ||
126 | /* Write output buffer and update the CRC-32 and total bytes written. write() | |
127 | is called until all of the output is written or an error is encountered. | |
128 | On success out() returns 0. For a write failure, out() returns 1. If the | |
129 | output file descriptor is -1, then nothing is written. | |
130 | */ | |
131 | local int out(void *out_desc, unsigned char *buf, unsigned len) | |
132 | { | |
133 | int ret; | |
134 | struct outd *me = (struct outd *)out_desc; | |
135 | ||
136 | if (me->check) { | |
137 | me->crc = crc32(me->crc, buf, len); | |
138 | me->total += len; | |
139 | } | |
140 | if (me->outfile != -1) | |
141 | do { | |
142 | ret = PIECE; | |
143 | if ((unsigned)ret > len) | |
144 | ret = (int)len; | |
145 | ret = (int)write(me->outfile, buf, ret); | |
146 | if (ret == -1) | |
147 | return 1; | |
148 | buf += ret; | |
149 | len -= ret; | |
150 | } while (len != 0); | |
151 | return 0; | |
152 | } | |
153 | ||
154 | /* next input byte macro for use inside lunpipe() and gunpipe() */ | |
155 | #define NEXT() (have ? 0 : (have = in(indp, &next)), \ | |
156 | last = have ? (have--, (int)(*next++)) : -1) | |
157 | ||
158 | /* memory for gunpipe() and lunpipe() -- | |
159 | the first 256 entries of prefix[] and suffix[] are never used, could | |
160 | have offset the index, but it's faster to waste the memory */ | |
161 | unsigned char inbuf[SIZE]; /* input buffer */ | |
162 | unsigned char outbuf[SIZE]; /* output buffer */ | |
163 | unsigned short prefix[65536]; /* index to LZW prefix string */ | |
164 | unsigned char suffix[65536]; /* one-character LZW suffix */ | |
165 | unsigned char match[65280 + 2]; /* buffer for reversed match or gzip | |
166 | 32K sliding window */ | |
167 | ||
168 | /* throw out what's left in the current bits byte buffer (this is a vestigial | |
169 | aspect of the compressed data format derived from an implementation that | |
170 | made use of a special VAX machine instruction!) */ | |
171 | #define FLUSHCODE() \ | |
172 | do { \ | |
173 | left = 0; \ | |
174 | rem = 0; \ | |
175 | if (chunk > have) { \ | |
176 | chunk -= have; \ | |
177 | have = 0; \ | |
178 | if (NEXT() == -1) \ | |
179 | break; \ | |
180 | chunk--; \ | |
181 | if (chunk > have) { \ | |
182 | chunk = have = 0; \ | |
183 | break; \ | |
184 | } \ | |
185 | } \ | |
186 | have -= chunk; \ | |
187 | next += chunk; \ | |
188 | chunk = 0; \ | |
189 | } while (0) | |
190 | ||
191 | /* Decompress a compress (LZW) file from indp to outfile. The compress magic | |
192 | header (two bytes) has already been read and verified. There are have bytes | |
193 | of buffered input at next. strm is used for passing error information back | |
194 | to gunpipe(). | |
195 | ||
196 | lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of | |
197 | file, read error, or write error (a write error indicated by strm->next_in | |
198 | not equal to Z_NULL), or Z_DATA_ERROR for invalid input. | |
199 | */ | |
da09a436 | 200 | local int lunpipe(unsigned have, z_const unsigned char *next, struct ind *indp, |
5ca28f79 L |
201 | int outfile, z_stream *strm) |
202 | { | |
203 | int last; /* last byte read by NEXT(), or -1 if EOF */ | |
204 | unsigned chunk; /* bytes left in current chunk */ | |
205 | int left; /* bits left in rem */ | |
206 | unsigned rem; /* unused bits from input */ | |
207 | int bits; /* current bits per code */ | |
208 | unsigned code; /* code, table traversal index */ | |
209 | unsigned mask; /* mask for current bits codes */ | |
210 | int max; /* maximum bits per code for this stream */ | |
211 | unsigned flags; /* compress flags, then block compress flag */ | |
212 | unsigned end; /* last valid entry in prefix/suffix tables */ | |
213 | unsigned temp; /* current code */ | |
214 | unsigned prev; /* previous code */ | |
215 | unsigned final; /* last character written for previous code */ | |
216 | unsigned stack; /* next position for reversed string */ | |
217 | unsigned outcnt; /* bytes in output buffer */ | |
218 | struct outd outd; /* output structure */ | |
219 | unsigned char *p; | |
220 | ||
221 | /* set up output */ | |
222 | outd.outfile = outfile; | |
223 | outd.check = 0; | |
224 | ||
225 | /* process remainder of compress header -- a flags byte */ | |
226 | flags = NEXT(); | |
227 | if (last == -1) | |
228 | return Z_BUF_ERROR; | |
229 | if (flags & 0x60) { | |
230 | strm->msg = (char *)"unknown lzw flags set"; | |
231 | return Z_DATA_ERROR; | |
232 | } | |
233 | max = flags & 0x1f; | |
234 | if (max < 9 || max > 16) { | |
235 | strm->msg = (char *)"lzw bits out of range"; | |
236 | return Z_DATA_ERROR; | |
237 | } | |
238 | if (max == 9) /* 9 doesn't really mean 9 */ | |
239 | max = 10; | |
240 | flags &= 0x80; /* true if block compress */ | |
241 | ||
242 | /* clear table */ | |
243 | bits = 9; | |
244 | mask = 0x1ff; | |
245 | end = flags ? 256 : 255; | |
246 | ||
247 | /* set up: get first 9-bit code, which is the first decompressed byte, but | |
248 | don't create a table entry until the next code */ | |
249 | if (NEXT() == -1) /* no compressed data is ok */ | |
250 | return Z_OK; | |
251 | final = prev = (unsigned)last; /* low 8 bits of code */ | |
252 | if (NEXT() == -1) /* missing a bit */ | |
253 | return Z_BUF_ERROR; | |
254 | if (last & 1) { /* code must be < 256 */ | |
255 | strm->msg = (char *)"invalid lzw code"; | |
256 | return Z_DATA_ERROR; | |
257 | } | |
258 | rem = (unsigned)last >> 1; /* remaining 7 bits */ | |
259 | left = 7; | |
260 | chunk = bits - 2; /* 7 bytes left in this chunk */ | |
261 | outbuf[0] = (unsigned char)final; /* write first decompressed byte */ | |
262 | outcnt = 1; | |
263 | ||
264 | /* decode codes */ | |
265 | stack = 0; | |
266 | for (;;) { | |
267 | /* if the table will be full after this, increment the code size */ | |
268 | if (end >= mask && bits < max) { | |
269 | FLUSHCODE(); | |
270 | bits++; | |
271 | mask <<= 1; | |
272 | mask++; | |
273 | } | |
274 | ||
275 | /* get a code of length bits */ | |
276 | if (chunk == 0) /* decrement chunk modulo bits */ | |
277 | chunk = bits; | |
278 | code = rem; /* low bits of code */ | |
279 | if (NEXT() == -1) { /* EOF is end of compressed data */ | |
280 | /* write remaining buffered output */ | |
281 | if (outcnt && out(&outd, outbuf, outcnt)) { | |
282 | strm->next_in = outbuf; /* signal write error */ | |
283 | return Z_BUF_ERROR; | |
284 | } | |
285 | return Z_OK; | |
286 | } | |
287 | code += (unsigned)last << left; /* middle (or high) bits of code */ | |
288 | left += 8; | |
289 | chunk--; | |
290 | if (bits > left) { /* need more bits */ | |
291 | if (NEXT() == -1) /* can't end in middle of code */ | |
292 | return Z_BUF_ERROR; | |
293 | code += (unsigned)last << left; /* high bits of code */ | |
294 | left += 8; | |
295 | chunk--; | |
296 | } | |
297 | code &= mask; /* mask to current code length */ | |
298 | left -= bits; /* number of unused bits */ | |
299 | rem = (unsigned)last >> (8 - left); /* unused bits from last byte */ | |
300 | ||
301 | /* process clear code (256) */ | |
302 | if (code == 256 && flags) { | |
303 | FLUSHCODE(); | |
304 | bits = 9; /* initialize bits and mask */ | |
305 | mask = 0x1ff; | |
306 | end = 255; /* empty table */ | |
307 | continue; /* get next code */ | |
308 | } | |
309 | ||
310 | /* special code to reuse last match */ | |
311 | temp = code; /* save the current code */ | |
312 | if (code > end) { | |
313 | /* Be picky on the allowed code here, and make sure that the code | |
314 | we drop through (prev) will be a valid index so that random | |
315 | input does not cause an exception. The code != end + 1 check is | |
316 | empirically derived, and not checked in the original uncompress | |
317 | code. If this ever causes a problem, that check could be safely | |
318 | removed. Leaving this check in greatly improves gun's ability | |
319 | to detect random or corrupted input after a compress header. | |
320 | In any case, the prev > end check must be retained. */ | |
321 | if (code != end + 1 || prev > end) { | |
322 | strm->msg = (char *)"invalid lzw code"; | |
323 | return Z_DATA_ERROR; | |
324 | } | |
325 | match[stack++] = (unsigned char)final; | |
326 | code = prev; | |
327 | } | |
328 | ||
329 | /* walk through linked list to generate output in reverse order */ | |
330 | p = match + stack; | |
331 | while (code >= 256) { | |
332 | *p++ = suffix[code]; | |
333 | code = prefix[code]; | |
334 | } | |
335 | stack = p - match; | |
336 | match[stack++] = (unsigned char)code; | |
337 | final = code; | |
338 | ||
339 | /* link new table entry */ | |
340 | if (end < mask) { | |
341 | end++; | |
342 | prefix[end] = (unsigned short)prev; | |
343 | suffix[end] = (unsigned char)final; | |
344 | } | |
345 | ||
346 | /* set previous code for next iteration */ | |
347 | prev = temp; | |
348 | ||
349 | /* write output in forward order */ | |
350 | while (stack > SIZE - outcnt) { | |
351 | while (outcnt < SIZE) | |
352 | outbuf[outcnt++] = match[--stack]; | |
353 | if (out(&outd, outbuf, outcnt)) { | |
354 | strm->next_in = outbuf; /* signal write error */ | |
355 | return Z_BUF_ERROR; | |
356 | } | |
357 | outcnt = 0; | |
358 | } | |
359 | p = match + stack; | |
360 | do { | |
361 | outbuf[outcnt++] = *--p; | |
362 | } while (p > match); | |
363 | stack = 0; | |
364 | ||
365 | /* loop for next code with final and prev as the last match, rem and | |
366 | left provide the first 0..7 bits of the next code, end is the last | |
367 | valid table entry */ | |
368 | } | |
369 | } | |
370 | ||
371 | /* Decompress a gzip file from infile to outfile. strm is assumed to have been | |
372 | successfully initialized with inflateBackInit(). The input file may consist | |
373 | of a series of gzip streams, in which case all of them will be decompressed | |
374 | to the output file. If outfile is -1, then the gzip stream(s) integrity is | |
375 | checked and nothing is written. | |
376 | ||
377 | The return value is a zlib error code: Z_MEM_ERROR if out of memory, | |
378 | Z_DATA_ERROR if the header or the compressed data is invalid, or if the | |
379 | trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends | |
380 | prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip | |
381 | stream) follows a valid gzip stream. | |
382 | */ | |
383 | local int gunpipe(z_stream *strm, int infile, int outfile) | |
384 | { | |
385 | int ret, first, last; | |
386 | unsigned have, flags, len; | |
da09a436 | 387 | z_const unsigned char *next = NULL; |
5ca28f79 L |
388 | struct ind ind, *indp; |
389 | struct outd outd; | |
390 | ||
391 | /* setup input buffer */ | |
392 | ind.infile = infile; | |
393 | ind.inbuf = inbuf; | |
394 | indp = &ind; | |
395 | ||
396 | /* decompress concatenated gzip streams */ | |
397 | have = 0; /* no input data read in yet */ | |
398 | first = 1; /* looking for first gzip header */ | |
399 | strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ | |
400 | for (;;) { | |
401 | /* look for the two magic header bytes for a gzip stream */ | |
402 | if (NEXT() == -1) { | |
403 | ret = Z_OK; | |
404 | break; /* empty gzip stream is ok */ | |
405 | } | |
406 | if (last != 31 || (NEXT() != 139 && last != 157)) { | |
407 | strm->msg = (char *)"incorrect header check"; | |
408 | ret = first ? Z_DATA_ERROR : Z_ERRNO; | |
409 | break; /* not a gzip or compress header */ | |
410 | } | |
411 | first = 0; /* next non-header is junk */ | |
412 | ||
413 | /* process a compress (LZW) file -- can't be concatenated after this */ | |
414 | if (last == 157) { | |
415 | ret = lunpipe(have, next, indp, outfile, strm); | |
416 | break; | |
417 | } | |
418 | ||
419 | /* process remainder of gzip header */ | |
420 | ret = Z_BUF_ERROR; | |
421 | if (NEXT() != 8) { /* only deflate method allowed */ | |
422 | if (last == -1) break; | |
423 | strm->msg = (char *)"unknown compression method"; | |
424 | ret = Z_DATA_ERROR; | |
425 | break; | |
426 | } | |
427 | flags = NEXT(); /* header flags */ | |
428 | NEXT(); /* discard mod time, xflgs, os */ | |
429 | NEXT(); | |
430 | NEXT(); | |
431 | NEXT(); | |
432 | NEXT(); | |
433 | NEXT(); | |
434 | if (last == -1) break; | |
435 | if (flags & 0xe0) { | |
436 | strm->msg = (char *)"unknown header flags set"; | |
437 | ret = Z_DATA_ERROR; | |
438 | break; | |
439 | } | |
440 | if (flags & 4) { /* extra field */ | |
441 | len = NEXT(); | |
442 | len += (unsigned)(NEXT()) << 8; | |
443 | if (last == -1) break; | |
444 | while (len > have) { | |
445 | len -= have; | |
446 | have = 0; | |
447 | if (NEXT() == -1) break; | |
448 | len--; | |
449 | } | |
450 | if (last == -1) break; | |
451 | have -= len; | |
452 | next += len; | |
453 | } | |
454 | if (flags & 8) /* file name */ | |
455 | while (NEXT() != 0 && last != -1) | |
456 | ; | |
457 | if (flags & 16) /* comment */ | |
458 | while (NEXT() != 0 && last != -1) | |
459 | ; | |
460 | if (flags & 2) { /* header crc */ | |
461 | NEXT(); | |
462 | NEXT(); | |
463 | } | |
464 | if (last == -1) break; | |
465 | ||
466 | /* set up output */ | |
467 | outd.outfile = outfile; | |
468 | outd.check = 1; | |
469 | outd.crc = crc32(0L, Z_NULL, 0); | |
470 | outd.total = 0; | |
471 | ||
472 | /* decompress data to output */ | |
473 | strm->next_in = next; | |
474 | strm->avail_in = have; | |
475 | ret = inflateBack(strm, in, indp, out, &outd); | |
476 | if (ret != Z_STREAM_END) break; | |
477 | next = strm->next_in; | |
478 | have = strm->avail_in; | |
479 | strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ | |
480 | ||
481 | /* check trailer */ | |
482 | ret = Z_BUF_ERROR; | |
483 | if (NEXT() != (int)(outd.crc & 0xff) || | |
484 | NEXT() != (int)((outd.crc >> 8) & 0xff) || | |
485 | NEXT() != (int)((outd.crc >> 16) & 0xff) || | |
486 | NEXT() != (int)((outd.crc >> 24) & 0xff)) { | |
487 | /* crc error */ | |
488 | if (last != -1) { | |
489 | strm->msg = (char *)"incorrect data check"; | |
490 | ret = Z_DATA_ERROR; | |
491 | } | |
492 | break; | |
493 | } | |
494 | if (NEXT() != (int)(outd.total & 0xff) || | |
495 | NEXT() != (int)((outd.total >> 8) & 0xff) || | |
496 | NEXT() != (int)((outd.total >> 16) & 0xff) || | |
497 | NEXT() != (int)((outd.total >> 24) & 0xff)) { | |
498 | /* length error */ | |
499 | if (last != -1) { | |
500 | strm->msg = (char *)"incorrect length check"; | |
501 | ret = Z_DATA_ERROR; | |
502 | } | |
503 | break; | |
504 | } | |
505 | ||
506 | /* go back and look for another gzip stream */ | |
507 | } | |
508 | ||
509 | /* clean up and return */ | |
510 | return ret; | |
511 | } | |
512 | ||
513 | /* Copy file attributes, from -> to, as best we can. This is best effort, so | |
514 | no errors are reported. The mode bits, including suid, sgid, and the sticky | |
515 | bit are copied (if allowed), the owner's user id and group id are copied | |
516 | (again if allowed), and the access and modify times are copied. */ | |
517 | local void copymeta(char *from, char *to) | |
518 | { | |
519 | struct stat was; | |
520 | struct utimbuf when; | |
521 | ||
522 | /* get all of from's Unix meta data, return if not a regular file */ | |
523 | if (stat(from, &was) != 0 || (was.st_mode & S_IFMT) != S_IFREG) | |
524 | return; | |
525 | ||
526 | /* set to's mode bits, ignore errors */ | |
527 | (void)chmod(to, was.st_mode & 07777); | |
528 | ||
529 | /* copy owner's user and group, ignore errors */ | |
530 | (void)chown(to, was.st_uid, was.st_gid); | |
531 | ||
532 | /* copy access and modify times, ignore errors */ | |
533 | when.actime = was.st_atime; | |
534 | when.modtime = was.st_mtime; | |
535 | (void)utime(to, &when); | |
536 | } | |
537 | ||
538 | /* Decompress the file inname to the file outnname, of if test is true, just | |
539 | decompress without writing and check the gzip trailer for integrity. If | |
540 | inname is NULL or an empty string, read from stdin. If outname is NULL or | |
541 | an empty string, write to stdout. strm is a pre-initialized inflateBack | |
542 | structure. When appropriate, copy the file attributes from inname to | |
543 | outname. | |
544 | ||
545 | gunzip() returns 1 if there is an out-of-memory error or an unexpected | |
546 | return code from gunpipe(). Otherwise it returns 0. | |
547 | */ | |
548 | local int gunzip(z_stream *strm, char *inname, char *outname, int test) | |
549 | { | |
550 | int ret; | |
551 | int infile, outfile; | |
552 | ||
553 | /* open files */ | |
554 | if (inname == NULL || *inname == 0) { | |
555 | inname = "-"; | |
556 | infile = 0; /* stdin */ | |
557 | } | |
558 | else { | |
559 | infile = open(inname, O_RDONLY, 0); | |
560 | if (infile == -1) { | |
561 | fprintf(stderr, "gun cannot open %s\n", inname); | |
562 | return 0; | |
563 | } | |
564 | } | |
565 | if (test) | |
566 | outfile = -1; | |
567 | else if (outname == NULL || *outname == 0) { | |
568 | outname = "-"; | |
569 | outfile = 1; /* stdout */ | |
570 | } | |
571 | else { | |
572 | outfile = open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0666); | |
573 | if (outfile == -1) { | |
574 | close(infile); | |
575 | fprintf(stderr, "gun cannot create %s\n", outname); | |
576 | return 0; | |
577 | } | |
578 | } | |
579 | errno = 0; | |
580 | ||
581 | /* decompress */ | |
582 | ret = gunpipe(strm, infile, outfile); | |
583 | if (outfile > 2) close(outfile); | |
584 | if (infile > 2) close(infile); | |
585 | ||
586 | /* interpret result */ | |
587 | switch (ret) { | |
588 | case Z_OK: | |
589 | case Z_ERRNO: | |
590 | if (infile > 2 && outfile > 2) { | |
591 | copymeta(inname, outname); /* copy attributes */ | |
592 | unlink(inname); | |
593 | } | |
594 | if (ret == Z_ERRNO) | |
595 | fprintf(stderr, "gun warning: trailing garbage ignored in %s\n", | |
596 | inname); | |
597 | break; | |
598 | case Z_DATA_ERROR: | |
599 | if (outfile > 2) unlink(outname); | |
600 | fprintf(stderr, "gun data error on %s: %s\n", inname, strm->msg); | |
601 | break; | |
602 | case Z_MEM_ERROR: | |
603 | if (outfile > 2) unlink(outname); | |
604 | fprintf(stderr, "gun out of memory error--aborting\n"); | |
605 | return 1; | |
606 | case Z_BUF_ERROR: | |
607 | if (outfile > 2) unlink(outname); | |
608 | if (strm->next_in != Z_NULL) { | |
609 | fprintf(stderr, "gun write error on %s: %s\n", | |
610 | outname, strerror(errno)); | |
611 | } | |
612 | else if (errno) { | |
613 | fprintf(stderr, "gun read error on %s: %s\n", | |
614 | inname, strerror(errno)); | |
615 | } | |
616 | else { | |
617 | fprintf(stderr, "gun unexpected end of file on %s\n", | |
618 | inname); | |
619 | } | |
620 | break; | |
621 | default: | |
622 | if (outfile > 2) unlink(outname); | |
623 | fprintf(stderr, "gun internal error--aborting\n"); | |
624 | return 1; | |
625 | } | |
626 | return 0; | |
627 | } | |
628 | ||
629 | /* Process the gun command line arguments. See the command syntax near the | |
630 | beginning of this source file. */ | |
631 | int main(int argc, char **argv) | |
632 | { | |
633 | int ret, len, test; | |
634 | char *outname; | |
635 | unsigned char *window; | |
636 | z_stream strm; | |
637 | ||
638 | /* initialize inflateBack state for repeated use */ | |
639 | window = match; /* reuse LZW match buffer */ | |
640 | strm.zalloc = Z_NULL; | |
641 | strm.zfree = Z_NULL; | |
642 | strm.opaque = Z_NULL; | |
643 | ret = inflateBackInit(&strm, 15, window); | |
644 | if (ret != Z_OK) { | |
645 | fprintf(stderr, "gun out of memory error--aborting\n"); | |
646 | return 1; | |
647 | } | |
648 | ||
649 | /* decompress each file to the same name with the suffix removed */ | |
650 | argc--; | |
651 | argv++; | |
652 | test = 0; | |
653 | if (argc && strcmp(*argv, "-h") == 0) { | |
654 | fprintf(stderr, "gun 1.6 (17 Jan 2010)\n"); | |
655 | fprintf(stderr, "Copyright (C) 2003-2010 Mark Adler\n"); | |
656 | fprintf(stderr, "usage: gun [-t] [file1.gz [file2.Z ...]]\n"); | |
657 | return 0; | |
658 | } | |
659 | if (argc && strcmp(*argv, "-t") == 0) { | |
660 | test = 1; | |
661 | argc--; | |
662 | argv++; | |
663 | } | |
664 | if (argc) | |
665 | do { | |
666 | if (test) | |
667 | outname = NULL; | |
668 | else { | |
669 | len = (int)strlen(*argv); | |
670 | if (strcmp(*argv + len - 3, ".gz") == 0 || | |
671 | strcmp(*argv + len - 3, "-gz") == 0) | |
672 | len -= 3; | |
673 | else if (strcmp(*argv + len - 2, ".z") == 0 || | |
674 | strcmp(*argv + len - 2, "-z") == 0 || | |
675 | strcmp(*argv + len - 2, "_z") == 0 || | |
676 | strcmp(*argv + len - 2, ".Z") == 0) | |
677 | len -= 2; | |
678 | else { | |
679 | fprintf(stderr, "gun error: no gz type on %s--skipping\n", | |
680 | *argv); | |
681 | continue; | |
682 | } | |
683 | outname = malloc(len + 1); | |
684 | if (outname == NULL) { | |
685 | fprintf(stderr, "gun out of memory error--aborting\n"); | |
686 | ret = 1; | |
687 | break; | |
688 | } | |
689 | memcpy(outname, *argv, len); | |
690 | outname[len] = 0; | |
691 | } | |
692 | ret = gunzip(&strm, *argv, outname, test); | |
693 | if (outname != NULL) free(outname); | |
694 | if (ret) break; | |
695 | } while (argv++, --argc); | |
696 | else | |
697 | ret = gunzip(&strm, NULL, NULL, test); | |
698 | ||
699 | /* clean up */ | |
700 | inflateBackEnd(&strm); | |
701 | return ret; | |
702 | } |