1 /* util.c -- utility functions for gzip support
3 Copyright (C) 1997-1999, 2001-2002, 2006, 2009-2018 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 3, 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. */
39 static int write_buffer (int, voidp
, unsigned int);
41 /* ========================================================================
42 * Table of CRC-32's of all single-byte values (made by makecrc.c)
44 static const ulg crc_32_tab
[] = {
45 0x00000000L
, 0x77073096L
, 0xee0e612cL
, 0x990951baL
, 0x076dc419L
,
46 0x706af48fL
, 0xe963a535L
, 0x9e6495a3L
, 0x0edb8832L
, 0x79dcb8a4L
,
47 0xe0d5e91eL
, 0x97d2d988L
, 0x09b64c2bL
, 0x7eb17cbdL
, 0xe7b82d07L
,
48 0x90bf1d91L
, 0x1db71064L
, 0x6ab020f2L
, 0xf3b97148L
, 0x84be41deL
,
49 0x1adad47dL
, 0x6ddde4ebL
, 0xf4d4b551L
, 0x83d385c7L
, 0x136c9856L
,
50 0x646ba8c0L
, 0xfd62f97aL
, 0x8a65c9ecL
, 0x14015c4fL
, 0x63066cd9L
,
51 0xfa0f3d63L
, 0x8d080df5L
, 0x3b6e20c8L
, 0x4c69105eL
, 0xd56041e4L
,
52 0xa2677172L
, 0x3c03e4d1L
, 0x4b04d447L
, 0xd20d85fdL
, 0xa50ab56bL
,
53 0x35b5a8faL
, 0x42b2986cL
, 0xdbbbc9d6L
, 0xacbcf940L
, 0x32d86ce3L
,
54 0x45df5c75L
, 0xdcd60dcfL
, 0xabd13d59L
, 0x26d930acL
, 0x51de003aL
,
55 0xc8d75180L
, 0xbfd06116L
, 0x21b4f4b5L
, 0x56b3c423L
, 0xcfba9599L
,
56 0xb8bda50fL
, 0x2802b89eL
, 0x5f058808L
, 0xc60cd9b2L
, 0xb10be924L
,
57 0x2f6f7c87L
, 0x58684c11L
, 0xc1611dabL
, 0xb6662d3dL
, 0x76dc4190L
,
58 0x01db7106L
, 0x98d220bcL
, 0xefd5102aL
, 0x71b18589L
, 0x06b6b51fL
,
59 0x9fbfe4a5L
, 0xe8b8d433L
, 0x7807c9a2L
, 0x0f00f934L
, 0x9609a88eL
,
60 0xe10e9818L
, 0x7f6a0dbbL
, 0x086d3d2dL
, 0x91646c97L
, 0xe6635c01L
,
61 0x6b6b51f4L
, 0x1c6c6162L
, 0x856530d8L
, 0xf262004eL
, 0x6c0695edL
,
62 0x1b01a57bL
, 0x8208f4c1L
, 0xf50fc457L
, 0x65b0d9c6L
, 0x12b7e950L
,
63 0x8bbeb8eaL
, 0xfcb9887cL
, 0x62dd1ddfL
, 0x15da2d49L
, 0x8cd37cf3L
,
64 0xfbd44c65L
, 0x4db26158L
, 0x3ab551ceL
, 0xa3bc0074L
, 0xd4bb30e2L
,
65 0x4adfa541L
, 0x3dd895d7L
, 0xa4d1c46dL
, 0xd3d6f4fbL
, 0x4369e96aL
,
66 0x346ed9fcL
, 0xad678846L
, 0xda60b8d0L
, 0x44042d73L
, 0x33031de5L
,
67 0xaa0a4c5fL
, 0xdd0d7cc9L
, 0x5005713cL
, 0x270241aaL
, 0xbe0b1010L
,
68 0xc90c2086L
, 0x5768b525L
, 0x206f85b3L
, 0xb966d409L
, 0xce61e49fL
,
69 0x5edef90eL
, 0x29d9c998L
, 0xb0d09822L
, 0xc7d7a8b4L
, 0x59b33d17L
,
70 0x2eb40d81L
, 0xb7bd5c3bL
, 0xc0ba6cadL
, 0xedb88320L
, 0x9abfb3b6L
,
71 0x03b6e20cL
, 0x74b1d29aL
, 0xead54739L
, 0x9dd277afL
, 0x04db2615L
,
72 0x73dc1683L
, 0xe3630b12L
, 0x94643b84L
, 0x0d6d6a3eL
, 0x7a6a5aa8L
,
73 0xe40ecf0bL
, 0x9309ff9dL
, 0x0a00ae27L
, 0x7d079eb1L
, 0xf00f9344L
,
74 0x8708a3d2L
, 0x1e01f268L
, 0x6906c2feL
, 0xf762575dL
, 0x806567cbL
,
75 0x196c3671L
, 0x6e6b06e7L
, 0xfed41b76L
, 0x89d32be0L
, 0x10da7a5aL
,
76 0x67dd4accL
, 0xf9b9df6fL
, 0x8ebeeff9L
, 0x17b7be43L
, 0x60b08ed5L
,
77 0xd6d6a3e8L
, 0xa1d1937eL
, 0x38d8c2c4L
, 0x4fdff252L
, 0xd1bb67f1L
,
78 0xa6bc5767L
, 0x3fb506ddL
, 0x48b2364bL
, 0xd80d2bdaL
, 0xaf0a1b4cL
,
79 0x36034af6L
, 0x41047a60L
, 0xdf60efc3L
, 0xa867df55L
, 0x316e8eefL
,
80 0x4669be79L
, 0xcb61b38cL
, 0xbc66831aL
, 0x256fd2a0L
, 0x5268e236L
,
81 0xcc0c7795L
, 0xbb0b4703L
, 0x220216b9L
, 0x5505262fL
, 0xc5ba3bbeL
,
82 0xb2bd0b28L
, 0x2bb45a92L
, 0x5cb36a04L
, 0xc2d7ffa7L
, 0xb5d0cf31L
,
83 0x2cd99e8bL
, 0x5bdeae1dL
, 0x9b64c2b0L
, 0xec63f226L
, 0x756aa39cL
,
84 0x026d930aL
, 0x9c0906a9L
, 0xeb0e363fL
, 0x72076785L
, 0x05005713L
,
85 0x95bf4a82L
, 0xe2b87a14L
, 0x7bb12baeL
, 0x0cb61b38L
, 0x92d28e9bL
,
86 0xe5d5be0dL
, 0x7cdcefb7L
, 0x0bdbdf21L
, 0x86d3d2d4L
, 0xf1d4e242L
,
87 0x68ddb3f8L
, 0x1fda836eL
, 0x81be16cdL
, 0xf6b9265bL
, 0x6fb077e1L
,
88 0x18b74777L
, 0x88085ae6L
, 0xff0f6a70L
, 0x66063bcaL
, 0x11010b5cL
,
89 0x8f659effL
, 0xf862ae69L
, 0x616bffd3L
, 0x166ccf45L
, 0xa00ae278L
,
90 0xd70dd2eeL
, 0x4e048354L
, 0x3903b3c2L
, 0xa7672661L
, 0xd06016f7L
,
91 0x4969474dL
, 0x3e6e77dbL
, 0xaed16a4aL
, 0xd9d65adcL
, 0x40df0b66L
,
92 0x37d83bf0L
, 0xa9bcae53L
, 0xdebb9ec5L
, 0x47b2cf7fL
, 0x30b5ffe9L
,
93 0xbdbdf21cL
, 0xcabac28aL
, 0x53b39330L
, 0x24b4a3a6L
, 0xbad03605L
,
94 0xcdd70693L
, 0x54de5729L
, 0x23d967bfL
, 0xb3667a2eL
, 0xc4614ab8L
,
95 0x5d681b02L
, 0x2a6f2b94L
, 0xb40bbe37L
, 0xc30c8ea1L
, 0x5a05df1bL
,
99 /* ===========================================================================
100 * Copy input to output unchanged: zcat == cat with --force.
101 * IN assertion: insize bytes have already been read in inbuf and inptr bytes
102 * already processed or copied.
105 int in
, out
; /* input and output file descriptors */
110 while (insize
> inptr
) {
111 write_buf(out
, (char*)inbuf
+ inptr
, insize
- inptr
);
112 bytes_out
+= insize
- inptr
;
113 got
= read_buffer (in
, (char *) inbuf
, INBUFSIZ
);
117 insize
= (unsigned)got
;
123 /* ===========================================================================
124 * Run a set of bytes through the crc shift register. If s is a NULL
125 * pointer, then initialize the crc shift register contents instead.
126 * Return the current crc in either case.
129 uch
*s
; /* pointer to bytes to pump through */
130 unsigned n
; /* number of bytes in s[] */
132 register ulg c
; /* temporary variable */
134 static ulg crc
= (ulg
)0xffffffffL
; /* shift register contents */
141 c
= crc_32_tab
[((int)c
^ (*s
++)) & 0xff] ^ (c
>> 8);
145 return c
^ 0xffffffffL
; /* (instead of ~c for 64-bit machines) */
148 /* ===========================================================================
149 * Clear input and output buffers
155 bytes_in
= bytes_out
= 0L;
158 /* ===========================================================================
159 * Fill the input buffer. This is called only when the buffer is empty.
161 int fill_inbuf(eof_ok
)
162 int eof_ok
; /* set if EOF acceptable as a result */
166 /* Read as much as possible */
169 len
= read_buffer (ifd
, (char *) inbuf
+ insize
, INBUFSIZ
- insize
);
176 } while (insize
< INBUFSIZ
);
179 if (eof_ok
) return EOF
;
184 bytes_in
+= (off_t
)insize
;
189 /* Like the standard read function, except do not attempt to read more
190 than INT_MAX bytes at a time. */
192 read_buffer (fd
, buf
, cnt
)
200 len
= read (fd
, buf
, cnt
);
202 #if defined F_SETFL && O_NONBLOCK && defined EAGAIN
203 /* Input files are opened O_NONBLOCK for security reasons. On some
204 file systems this can cause read to fail with errno == EAGAIN. */
205 if (len
< 0 && errno
== EAGAIN
)
207 int flags
= fcntl (fd
, F_GETFL
);
210 if (! (flags
& O_NONBLOCK
))
212 else if (fcntl (fd
, F_SETFL
, flags
& ~O_NONBLOCK
) != -1)
213 len
= read (fd
, buf
, cnt
);
221 /* Likewise for 'write'. */
223 write_buffer (fd
, buf
, cnt
)
230 return write (fd
, buf
, cnt
);
233 /* ===========================================================================
234 * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
235 * (used for the compressed data only)
239 if (outcnt
== 0) return;
241 write_buf(ofd
, (char *)outbuf
, outcnt
);
242 bytes_out
+= (off_t
)outcnt
;
246 /* ===========================================================================
247 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
248 * (Used for the decompressed data only.)
252 if (outcnt
== 0) return;
253 updcrc(window
, outcnt
);
256 write_buf(ofd
, (char *)window
, outcnt
);
258 bytes_out
+= (off_t
)outcnt
;
262 /* ===========================================================================
263 * Does the same as write(), but also handles partial pipe writes and checks
266 void write_buf(fd
, buf
, cnt
)
273 while ((n
= write_buffer (fd
, buf
, cnt
)) != cnt
) {
274 if (n
== (unsigned)(-1)) {
278 buf
= (voidp
)((char*)buf
+n
);
282 /* ========================================================================
283 * Put string s in lower case, return s.
290 *t
= tolow ((unsigned char) *t
);
294 /* ========================================================================
295 * Return the base name of a file (remove any directory prefix and
296 * any version suffix). For systems with file names that are not
297 * case sensitive, force the base name to lower case.
300 gzip_base_name (fname
)
303 fname
= last_component (fname
);
304 if (casemap('A') == 'a') strlwr(fname
);
308 /* ========================================================================
309 * Unlink a file, working around the unlink readonly bug (if present).
311 int xunlink (filename
)
314 int r
= unlink (filename
);
316 #ifdef UNLINK_READONLY_BUG
320 if (chmod (filename
, S_IWUSR
) != 0)
326 r
= unlink (filename
);
333 /* ========================================================================
334 * Make a file name legal for file systems not allowing file names with
335 * multiple dots or starting with a dot (such as MSDOS), by changing
336 * all dots except the last one into underlines. A target dependent
337 * function can be used instead of this simple function by defining the macro
338 * MAKE_LEGAL_NAME in tailor.h and providing the function in a target
341 void make_simple_name(name
)
344 char *p
= strrchr(name
, '.');
345 if (p
== NULL
) return;
348 if (*--p
== '.') *p
= '_';
352 /* Convert the value of the environment variable ENVVAR_NAME
353 to a newly allocated argument vector, and set *ARGCP and *ARGVP
354 to the number of arguments and to the vector, respectively.
355 Make the new vector's zeroth element equal to the old **ARGVP.
356 Return a pointer to the newly allocated string storage.
358 If the vector would be empty, do not allocate storage,
359 do not set *ARGCP and *ARGVP, and return NULL. */
361 #define SEPARATOR " \t" /* separators in env variable */
364 int *argcp
, /* pointer to argc */
365 char ***argvp
, /* pointer to argv */
366 char const *envvar_name
) /* name of environment variable */
368 char *p
; /* running pointer through env variable */
369 char **oargv
; /* runs through old argv array */
370 char **nargv
; /* runs through new argv array */
371 int nargc
= 0; /* number of arguments in env variable */
374 env_val
= getenv(envvar_name
);
375 if (env_val
== NULL
) return NULL
;
377 env_val
= xstrdup (env_val
);
379 for (p
= env_val
; *p
; nargc
++ ) { /* move through env_val */
380 p
+= strspn(p
, SEPARATOR
); /* skip leading separators */
381 if (*p
== '\0') break;
383 p
+= strcspn(p
, SEPARATOR
); /* find end of word */
384 if (*p
) *p
++ = '\0'; /* mark it */
391 /* Allocate the new argv array, with an extra element just in case
392 * the original arg list did not end with a NULL.
394 nargv
= xcalloc (*argcp
+ 1, sizeof (char *));
398 /* Copy the program name first */
401 /* Then copy the environment args */
402 for (p
= env_val
; nargc
> 0; nargc
--) {
403 p
+= strspn(p
, SEPARATOR
); /* skip separators */
404 *(nargv
++) = p
; /* store start */
405 while (*p
++) ; /* skip over word */
412 /* ========================================================================
416 gzip_error (char const *m
)
418 fprintf (stderr
, "\n%s: %s: %s\n", program_name
, ifname
, m
);
425 fprintf (stderr
, "\n%s: memory_exhausted\n", program_name
);
429 void warning (char const *m
)
431 WARN ((stderr
, "%s: %s: warning: %s\n", program_name
, ifname
, m
));
437 fprintf (stderr
, "\n%s: ", program_name
);
442 fprintf(stderr
, "%s: unexpected end of file\n", ifname
);
450 fprintf (stderr
, "\n%s: ", program_name
);
456 /* ========================================================================
457 * Display compression ratio on the given stream on 6 characters.
459 void display_ratio(num
, den
, file
)
464 fprintf(file
, "%5.1f%%", den
== 0 ? 0 : 100.0 * num
/ den
);
467 /* ========================================================================
468 * Print an off_t. There's no completely portable way to use printf,
469 * so we do it ourselves.
471 void fprint_off(file
, offset
, width
)
476 char buf
[CHAR_BIT
* sizeof (off_t
)];
477 char *p
= buf
+ sizeof buf
;
479 /* Don't negate offset here; it might overflow. */
482 *--p
= '0' - offset
% 10;
483 while ((offset
/= 10) != 0);
488 *--p
= '0' + offset
% 10;
489 while ((offset
/= 10) != 0);
492 width
-= buf
+ sizeof buf
- p
;
493 while (0 < width
--) {
496 for (; p
< buf
+ sizeof buf
; p
++)