Mercurial > hgrepos > Python2 > PyMuPDF
comparison mupdf-source/thirdparty/zlib/examples/gun.c @ 2:b50eed0cc0ef upstream
ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4.
The directory name has changed: no version number in the expanded directory now.
| author | Franz Glasner <fzglas.hg@dom66.de> |
|---|---|
| date | Mon, 15 Sep 2025 11:43:07 +0200 |
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| 1:1d09e1dec1d9 | 2:b50eed0cc0ef |
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| 1 /* gun.c -- simple gunzip to give an example of the use of inflateBack() | |
| 2 * Copyright (C) 2003, 2005, 2008, 2010, 2012 Mark Adler | |
| 3 * For conditions of distribution and use, see copyright notice in zlib.h | |
| 4 Version 1.7 12 August 2012 Mark Adler */ | |
| 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 | |
| 21 1.7 12 Aug 2012 Update for z_const usage in zlib 1.2.8 | |
| 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 concatenated. If a Unix compress stream is | |
| 47 encountered in an input file, it is the last stream in that file. | |
| 48 | |
| 49 Like gunzip and uncompress, the file attributes of the original compressed | |
| 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. */ | |
| 89 local unsigned in(void *in_desc, z_const unsigned char **buf) | |
| 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 */ | |
| 200 local int lunpipe(unsigned have, z_const unsigned char *next, struct ind *indp, | |
| 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; | |
| 387 z_const unsigned char *next = NULL; | |
| 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 } |
