1 /* util.c -- utility functions for gzip support
3 Copyright (C) 1997, 1998, 1999, 2001, 2002, 2006 Free Software
5 Copyright (C) 1992-1993 Jean-loup Gailly
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software Foundation,
19 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
22 static char rcsid[] = "$Id: util.c,v 1.6 2006/12/11 18:54:39 eggert Exp $";
41 #if defined STDC_HEADERS || defined HAVE_STDLIB_H
55 static int write_buffer OF((int, voidp, unsigned int));
57 extern ulg crc_32_tab[]; /* crc table, defined below */
59 /* ===========================================================================
60 * Copy input to output unchanged: zcat == cat with --force.
61 * IN assertion: insize bytes have already been read in inbuf.
64 int in, out; /* input and output file descriptors */
67 while (insize != 0 && (int)insize != -1) {
68 write_buf(out, (char*)inbuf, insize);
70 insize = read_buffer (in, (char *) inbuf, INBUFSIZ);
72 if ((int)insize == -1) {
79 /* ===========================================================================
80 * Run a set of bytes through the crc shift register. If s is a NULL
81 * pointer, then initialize the crc shift register contents instead.
82 * Return the current crc in either case.
85 uch *s; /* pointer to bytes to pump through */
86 unsigned n; /* number of bytes in s[] */
88 register ulg c; /* temporary variable */
90 static ulg crc = (ulg)0xffffffffL; /* shift register contents */
97 c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
101 return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */
104 /* ===========================================================================
105 * Clear input and output buffers
111 bytes_in = bytes_out = 0L;
114 /* ===========================================================================
115 * Fill the input buffer. This is called only when the buffer is empty.
117 int fill_inbuf(eof_ok)
118 int eof_ok; /* set if EOF acceptable as a result */
122 /* Read as much as possible */
125 len = read_buffer (ifd, (char *) inbuf + insize, INBUFSIZ - insize);
132 } while (insize < INBUFSIZ);
135 if (eof_ok) return EOF;
140 bytes_in += (off_t)insize;
145 /* Like the standard read function, except do not attempt to read more
146 than SSIZE_MAX bytes at a time. */
148 read_buffer (fd, buf, cnt)
157 return read (fd, buf, cnt);
160 /* Likewise for 'write'. */
162 write_buffer (fd, buf, cnt)
171 return write (fd, buf, cnt);
174 /* ===========================================================================
175 * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
176 * (used for the compressed data only)
180 if (outcnt == 0) return;
182 write_buf(ofd, (char *)outbuf, outcnt);
183 bytes_out += (off_t)outcnt;
187 /* ===========================================================================
188 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
189 * (Used for the decompressed data only.)
193 if (outcnt == 0) return;
194 updcrc(window, outcnt);
197 write_buf(ofd, (char *)window, outcnt);
199 bytes_out += (off_t)outcnt;
203 /* ===========================================================================
204 * Does the same as write(), but also handles partial pipe writes and checks
207 void write_buf(fd, buf, cnt)
214 while ((n = write_buffer (fd, buf, cnt)) != cnt) {
215 if (n == (unsigned)(-1)) {
219 buf = (voidp)((char*)buf+n);
223 /* ========================================================================
224 * Put string s in lower case, return s.
231 *t = tolow ((unsigned char) *t);
235 /* ========================================================================
236 * Return the base name of a file (remove any directory prefix and
237 * any version suffix). For systems with file names that are not
238 * case sensitive, force the base name to lower case.
241 gzip_base_name (fname)
246 if ((p = strrchr(fname, PATH_SEP)) != NULL) fname = p+1;
248 if ((p = strrchr(fname, PATH_SEP2)) != NULL) fname = p+1;
251 if ((p = strrchr(fname, PATH_SEP3)) != NULL) fname = p+1;
254 if ((p = strrchr(fname, SUFFIX_SEP)) != NULL) *p = '\0';
256 if (casemap('A') == 'a') strlwr(fname);
260 /* ========================================================================
261 * Unlink a file, working around the unlink readonly bug (if present).
263 int xunlink (filename)
266 int r = unlink (filename);
268 #ifdef UNLINK_READONLY_BUG
272 if (chmod (filename, S_IWUSR) != 0)
278 r = unlink (filename);
285 /* ========================================================================
286 * Make a file name legal for file systems not allowing file names with
287 * multiple dots or starting with a dot (such as MSDOS), by changing
288 * all dots except the last one into underlines. A target dependent
289 * function can be used instead of this simple function by defining the macro
290 * MAKE_LEGAL_NAME in tailor.h and providing the function in a target
293 void make_simple_name(name)
296 char *p = strrchr(name, '.');
297 if (p == NULL) return;
300 if (*--p == '.') *p = '_';
305 #if !defined HAVE_STRING_H && !defined STDC_HEADERS
307 /* Provide missing strspn and strcspn functions. */
313 int strspn OF((const char *s, const char *accept));
314 int strcspn OF((const char *s, const char *reject));
316 /* ========================================================================
317 * Return the length of the maximum initial segment
318 * of s which contains only characters in accept.
320 int strspn(s, accept)
324 register const char *p;
325 register const char *a;
326 register int count = 0;
328 for (p = s; *p != '\0'; ++p) {
329 for (a = accept; *a != '\0'; ++a) {
332 if (*a == '\0') return count;
338 /* ========================================================================
339 * Return the length of the maximum inital segment of s
340 * which contains no characters from reject.
342 int strcspn(s, reject)
346 register int count = 0;
349 if (strchr(reject, *s++) != NULL) return count;
357 /* ========================================================================
358 * Add an environment variable (if any) before argv, and update argc.
359 * Return the expanded environment variable to be freed later, or NULL
360 * if no options were added to argv.
362 #define SEPARATOR " \t" /* separators in env variable */
364 char *add_envopt(argcp, argvp, env)
365 int *argcp; /* pointer to argc */
366 char ***argvp; /* pointer to argv */
367 char *env; /* name of environment variable */
369 char *p; /* running pointer through env variable */
370 char **oargv; /* runs through old argv array */
371 char **nargv; /* runs through new argv array */
372 int oargc = *argcp; /* old argc */
373 int nargc = 0; /* number of arguments in env variable */
375 env = (char*)getenv(env);
376 if (env == NULL) return NULL;
380 for (p = env; *p; nargc++ ) { /* move through env */
381 p += strspn(p, SEPARATOR); /* skip leading separators */
382 if (*p == '\0') break;
384 p += strcspn(p, SEPARATOR); /* find end of word */
385 if (*p) *p++ = '\0'; /* mark it */
392 /* Allocate the new argv array, with an extra element just in case
393 * the original arg list did not end with a NULL.
395 nargv = (char **) xcalloc (*argcp + 1, sizeof (char *));
399 /* Copy the program name first */
401 gzip_error ("argc<=0");
402 *(nargv++) = *(oargv++);
404 /* Then copy the environment args */
405 for (p = env; nargc > 0; nargc--) {
406 p += strspn(p, SEPARATOR); /* skip separators */
407 *(nargv++) = p; /* store start */
408 while (*p++) ; /* skip over word */
411 /* Finally copy the old args and add a NULL (usual convention) */
412 while (oargc--) *(nargv++) = *(oargv++);
417 /* ========================================================================
424 fprintf (stderr, "\n%s: %s: %s\n", program_name, ifname, m);
431 fprintf (stderr, "\n%s: memory_exhausted\n", program_name);
438 WARN ((stderr, "%s: %s: warning: %s\n", program_name, ifname, m));
444 fprintf (stderr, "\n%s: ", program_name);
449 fprintf(stderr, "%s: unexpected end of file\n", ifname);
457 fprintf (stderr, "\n%s: ", program_name);
463 /* ========================================================================
464 * Display compression ratio on the given stream on 6 characters.
466 void display_ratio(num, den, file)
471 fprintf(file, "%5.1f%%", den == 0 ? 0 : 100.0 * num / den);
474 /* ========================================================================
475 * Print an off_t. There's no completely portable way to use printf,
476 * so we do it ourselves.
478 void fprint_off(file, offset, width)
483 char buf[CHAR_BIT * sizeof (off_t)];
484 char *p = buf + sizeof buf;
486 /* Don't negate offset here; it might overflow. */
489 *--p = '0' - offset % 10;
490 while ((offset /= 10) != 0);
495 *--p = '0' + offset % 10;
496 while ((offset /= 10) != 0);
499 width -= buf + sizeof buf - p;
500 while (0 < width--) {
503 for (; p < buf + sizeof buf; p++)
507 /* ========================================================================
508 * Table of CRC-32's of all single-byte values (made by makecrc.c)
511 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
512 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
513 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
514 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
515 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
516 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
517 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
518 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
519 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
520 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
521 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
522 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
523 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
524 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
525 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
526 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
527 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
528 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
529 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
530 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
531 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
532 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
533 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
534 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
535 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
536 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
537 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
538 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
539 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
540 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
541 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
542 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
543 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
544 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
545 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
546 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
547 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
548 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
549 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
550 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
551 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
552 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
553 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
554 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
555 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
556 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
557 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
558 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
559 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
560 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
561 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,