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5ca28f79 | 1 | /* gzlib.c -- zlib functions common to reading and writing gzip files |
da09a436 | 2 | * Copyright (C) 2004, 2010, 2011, 2012, 2013 Mark Adler |
5ca28f79 L |
3 | * For conditions of distribution and use, see copyright notice in zlib.h |
4 | */ | |
5 | ||
6 | #include "gzguts.h" | |
7 | ||
8 | #if defined(_WIN32) && !defined(__BORLANDC__) | |
9 | # define LSEEK _lseeki64 | |
10 | #else | |
11 | #if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0 | |
12 | # define LSEEK lseek64 | |
13 | #else | |
14 | # define LSEEK lseek | |
15 | #endif | |
16 | #endif | |
17 | ||
18 | /* Local functions */ | |
19 | local void gz_reset OF((gz_statep)); | |
20 | local gzFile gz_open OF((const void *, int, const char *)); | |
21 | ||
22 | #if defined UNDER_CE | |
23 | ||
24 | /* Map the Windows error number in ERROR to a locale-dependent error message | |
25 | string and return a pointer to it. Typically, the values for ERROR come | |
26 | from GetLastError. | |
27 | ||
28 | The string pointed to shall not be modified by the application, but may be | |
29 | overwritten by a subsequent call to gz_strwinerror | |
30 | ||
31 | The gz_strwinerror function does not change the current setting of | |
32 | GetLastError. */ | |
33 | char ZLIB_INTERNAL *gz_strwinerror (error) | |
34 | DWORD error; | |
35 | { | |
36 | static char buf[1024]; | |
37 | ||
38 | wchar_t *msgbuf; | |
39 | DWORD lasterr = GetLastError(); | |
40 | DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | |
41 | | FORMAT_MESSAGE_ALLOCATE_BUFFER, | |
42 | NULL, | |
43 | error, | |
44 | 0, /* Default language */ | |
45 | (LPVOID)&msgbuf, | |
46 | 0, | |
47 | NULL); | |
48 | if (chars != 0) { | |
49 | /* If there is an \r\n appended, zap it. */ | |
50 | if (chars >= 2 | |
51 | && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') { | |
52 | chars -= 2; | |
53 | msgbuf[chars] = 0; | |
54 | } | |
55 | ||
56 | if (chars > sizeof (buf) - 1) { | |
57 | chars = sizeof (buf) - 1; | |
58 | msgbuf[chars] = 0; | |
59 | } | |
60 | ||
61 | wcstombs(buf, msgbuf, chars + 1); | |
62 | LocalFree(msgbuf); | |
63 | } | |
64 | else { | |
65 | sprintf(buf, "unknown win32 error (%ld)", error); | |
66 | } | |
67 | ||
68 | SetLastError(lasterr); | |
69 | return buf; | |
70 | } | |
71 | ||
72 | #endif /* UNDER_CE */ | |
73 | ||
74 | /* Reset gzip file state */ | |
75 | local void gz_reset(state) | |
76 | gz_statep state; | |
77 | { | |
78 | state->x.have = 0; /* no output data available */ | |
79 | if (state->mode == GZ_READ) { /* for reading ... */ | |
80 | state->eof = 0; /* not at end of file */ | |
81 | state->past = 0; /* have not read past end yet */ | |
82 | state->how = LOOK; /* look for gzip header */ | |
83 | } | |
84 | state->seek = 0; /* no seek request pending */ | |
85 | gz_error(state, Z_OK, NULL); /* clear error */ | |
86 | state->x.pos = 0; /* no uncompressed data yet */ | |
87 | state->strm.avail_in = 0; /* no input data yet */ | |
88 | } | |
89 | ||
90 | /* Open a gzip file either by name or file descriptor. */ | |
91 | local gzFile gz_open(path, fd, mode) | |
92 | const void *path; | |
93 | int fd; | |
94 | const char *mode; | |
95 | { | |
96 | gz_statep state; | |
97 | size_t len; | |
98 | int oflag; | |
99 | #ifdef O_CLOEXEC | |
100 | int cloexec = 0; | |
101 | #endif | |
102 | #ifdef O_EXCL | |
103 | int exclusive = 0; | |
104 | #endif | |
105 | ||
106 | /* check input */ | |
107 | if (path == NULL) | |
108 | return NULL; | |
109 | ||
110 | /* allocate gzFile structure to return */ | |
da09a436 | 111 | state = (gz_statep)malloc(sizeof(gz_state)); |
5ca28f79 L |
112 | if (state == NULL) |
113 | return NULL; | |
114 | state->size = 0; /* no buffers allocated yet */ | |
115 | state->want = GZBUFSIZE; /* requested buffer size */ | |
116 | state->msg = NULL; /* no error message yet */ | |
117 | ||
118 | /* interpret mode */ | |
119 | state->mode = GZ_NONE; | |
120 | state->level = Z_DEFAULT_COMPRESSION; | |
121 | state->strategy = Z_DEFAULT_STRATEGY; | |
122 | state->direct = 0; | |
123 | while (*mode) { | |
124 | if (*mode >= '0' && *mode <= '9') | |
125 | state->level = *mode - '0'; | |
126 | else | |
127 | switch (*mode) { | |
128 | case 'r': | |
129 | state->mode = GZ_READ; | |
130 | break; | |
131 | #ifndef NO_GZCOMPRESS | |
132 | case 'w': | |
133 | state->mode = GZ_WRITE; | |
134 | break; | |
135 | case 'a': | |
136 | state->mode = GZ_APPEND; | |
137 | break; | |
138 | #endif | |
139 | case '+': /* can't read and write at the same time */ | |
140 | free(state); | |
141 | return NULL; | |
142 | case 'b': /* ignore -- will request binary anyway */ | |
143 | break; | |
144 | #ifdef O_CLOEXEC | |
145 | case 'e': | |
146 | cloexec = 1; | |
147 | break; | |
148 | #endif | |
149 | #ifdef O_EXCL | |
150 | case 'x': | |
151 | exclusive = 1; | |
152 | break; | |
153 | #endif | |
154 | case 'f': | |
155 | state->strategy = Z_FILTERED; | |
156 | break; | |
157 | case 'h': | |
158 | state->strategy = Z_HUFFMAN_ONLY; | |
159 | break; | |
160 | case 'R': | |
161 | state->strategy = Z_RLE; | |
162 | break; | |
163 | case 'F': | |
164 | state->strategy = Z_FIXED; | |
da09a436 | 165 | break; |
5ca28f79 L |
166 | case 'T': |
167 | state->direct = 1; | |
da09a436 | 168 | break; |
5ca28f79 L |
169 | default: /* could consider as an error, but just ignore */ |
170 | ; | |
171 | } | |
172 | mode++; | |
173 | } | |
174 | ||
175 | /* must provide an "r", "w", or "a" */ | |
176 | if (state->mode == GZ_NONE) { | |
177 | free(state); | |
178 | return NULL; | |
179 | } | |
180 | ||
181 | /* can't force transparent read */ | |
182 | if (state->mode == GZ_READ) { | |
183 | if (state->direct) { | |
184 | free(state); | |
185 | return NULL; | |
186 | } | |
187 | state->direct = 1; /* for empty file */ | |
188 | } | |
189 | ||
190 | /* save the path name for error messages */ | |
191 | #ifdef _WIN32 | |
192 | if (fd == -2) { | |
193 | len = wcstombs(NULL, path, 0); | |
194 | if (len == (size_t)-1) | |
195 | len = 0; | |
196 | } | |
197 | else | |
198 | #endif | |
da09a436 JB |
199 | len = strlen((const char *)path); |
200 | state->path = (char *)malloc(len + 1); | |
5ca28f79 L |
201 | if (state->path == NULL) { |
202 | free(state); | |
203 | return NULL; | |
204 | } | |
205 | #ifdef _WIN32 | |
206 | if (fd == -2) | |
207 | if (len) | |
208 | wcstombs(state->path, path, len + 1); | |
209 | else | |
210 | *(state->path) = 0; | |
211 | else | |
212 | #endif | |
da09a436 JB |
213 | #if !defined(NO_snprintf) && !defined(NO_vsnprintf) |
214 | snprintf(state->path, len + 1, "%s", (const char *)path); | |
215 | #else | |
5ca28f79 | 216 | strcpy(state->path, path); |
da09a436 | 217 | #endif |
5ca28f79 L |
218 | |
219 | /* compute the flags for open() */ | |
220 | oflag = | |
221 | #ifdef O_LARGEFILE | |
222 | O_LARGEFILE | | |
223 | #endif | |
224 | #ifdef O_BINARY | |
225 | O_BINARY | | |
226 | #endif | |
227 | #ifdef O_CLOEXEC | |
228 | (cloexec ? O_CLOEXEC : 0) | | |
229 | #endif | |
230 | (state->mode == GZ_READ ? | |
231 | O_RDONLY : | |
232 | (O_WRONLY | O_CREAT | | |
233 | #ifdef O_EXCL | |
234 | (exclusive ? O_EXCL : 0) | | |
235 | #endif | |
236 | (state->mode == GZ_WRITE ? | |
237 | O_TRUNC : | |
238 | O_APPEND))); | |
239 | ||
240 | /* open the file with the appropriate flags (or just use fd) */ | |
241 | state->fd = fd > -1 ? fd : ( | |
242 | #ifdef _WIN32 | |
243 | fd == -2 ? _wopen(path, oflag, 0666) : | |
244 | #endif | |
da09a436 | 245 | open((const char *)path, oflag, 0666)); |
5ca28f79 L |
246 | if (state->fd == -1) { |
247 | free(state->path); | |
248 | free(state); | |
249 | return NULL; | |
250 | } | |
251 | if (state->mode == GZ_APPEND) | |
252 | state->mode = GZ_WRITE; /* simplify later checks */ | |
253 | ||
254 | /* save the current position for rewinding (only if reading) */ | |
255 | if (state->mode == GZ_READ) { | |
256 | state->start = LSEEK(state->fd, 0, SEEK_CUR); | |
257 | if (state->start == -1) state->start = 0; | |
258 | } | |
259 | ||
260 | /* initialize stream */ | |
261 | gz_reset(state); | |
262 | ||
263 | /* return stream */ | |
264 | return (gzFile)state; | |
265 | } | |
266 | ||
267 | /* -- see zlib.h -- */ | |
268 | gzFile ZEXPORT gzopen(path, mode) | |
269 | const char *path; | |
270 | const char *mode; | |
271 | { | |
272 | return gz_open(path, -1, mode); | |
273 | } | |
274 | ||
275 | /* -- see zlib.h -- */ | |
276 | gzFile ZEXPORT gzopen64(path, mode) | |
277 | const char *path; | |
278 | const char *mode; | |
279 | { | |
280 | return gz_open(path, -1, mode); | |
281 | } | |
282 | ||
283 | /* -- see zlib.h -- */ | |
284 | gzFile ZEXPORT gzdopen(fd, mode) | |
285 | int fd; | |
286 | const char *mode; | |
287 | { | |
288 | char *path; /* identifier for error messages */ | |
289 | gzFile gz; | |
290 | ||
da09a436 | 291 | if (fd == -1 || (path = (char *)malloc(7 + 3 * sizeof(int))) == NULL) |
5ca28f79 | 292 | return NULL; |
da09a436 JB |
293 | #if !defined(NO_snprintf) && !defined(NO_vsnprintf) |
294 | snprintf(path, 7 + 3 * sizeof(int), "<fd:%d>", fd); /* for debugging */ | |
295 | #else | |
5ca28f79 | 296 | sprintf(path, "<fd:%d>", fd); /* for debugging */ |
da09a436 | 297 | #endif |
5ca28f79 L |
298 | gz = gz_open(path, fd, mode); |
299 | free(path); | |
300 | return gz; | |
301 | } | |
302 | ||
303 | /* -- see zlib.h -- */ | |
304 | #ifdef _WIN32 | |
305 | gzFile ZEXPORT gzopen_w(path, mode) | |
306 | const wchar_t *path; | |
307 | const char *mode; | |
308 | { | |
309 | return gz_open(path, -2, mode); | |
310 | } | |
311 | #endif | |
312 | ||
313 | /* -- see zlib.h -- */ | |
314 | int ZEXPORT gzbuffer(file, size) | |
315 | gzFile file; | |
316 | unsigned size; | |
317 | { | |
318 | gz_statep state; | |
319 | ||
320 | /* get internal structure and check integrity */ | |
321 | if (file == NULL) | |
322 | return -1; | |
323 | state = (gz_statep)file; | |
324 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
325 | return -1; | |
326 | ||
327 | /* make sure we haven't already allocated memory */ | |
328 | if (state->size != 0) | |
329 | return -1; | |
330 | ||
331 | /* check and set requested size */ | |
332 | if (size < 2) | |
333 | size = 2; /* need two bytes to check magic header */ | |
334 | state->want = size; | |
335 | return 0; | |
336 | } | |
337 | ||
338 | /* -- see zlib.h -- */ | |
339 | int ZEXPORT gzrewind(file) | |
340 | gzFile file; | |
341 | { | |
342 | gz_statep state; | |
343 | ||
344 | /* get internal structure */ | |
345 | if (file == NULL) | |
346 | return -1; | |
347 | state = (gz_statep)file; | |
348 | ||
349 | /* check that we're reading and that there's no error */ | |
350 | if (state->mode != GZ_READ || | |
351 | (state->err != Z_OK && state->err != Z_BUF_ERROR)) | |
352 | return -1; | |
353 | ||
354 | /* back up and start over */ | |
355 | if (LSEEK(state->fd, state->start, SEEK_SET) == -1) | |
356 | return -1; | |
357 | gz_reset(state); | |
358 | return 0; | |
359 | } | |
360 | ||
361 | /* -- see zlib.h -- */ | |
362 | z_off64_t ZEXPORT gzseek64(file, offset, whence) | |
363 | gzFile file; | |
364 | z_off64_t offset; | |
365 | int whence; | |
366 | { | |
367 | unsigned n; | |
368 | z_off64_t ret; | |
369 | gz_statep state; | |
370 | ||
371 | /* get internal structure and check integrity */ | |
372 | if (file == NULL) | |
373 | return -1; | |
374 | state = (gz_statep)file; | |
375 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
376 | return -1; | |
377 | ||
378 | /* check that there's no error */ | |
379 | if (state->err != Z_OK && state->err != Z_BUF_ERROR) | |
380 | return -1; | |
381 | ||
382 | /* can only seek from start or relative to current position */ | |
383 | if (whence != SEEK_SET && whence != SEEK_CUR) | |
384 | return -1; | |
385 | ||
386 | /* normalize offset to a SEEK_CUR specification */ | |
387 | if (whence == SEEK_SET) | |
388 | offset -= state->x.pos; | |
389 | else if (state->seek) | |
390 | offset += state->skip; | |
391 | state->seek = 0; | |
392 | ||
393 | /* if within raw area while reading, just go there */ | |
394 | if (state->mode == GZ_READ && state->how == COPY && | |
395 | state->x.pos + offset >= 0) { | |
396 | ret = LSEEK(state->fd, offset - state->x.have, SEEK_CUR); | |
397 | if (ret == -1) | |
398 | return -1; | |
399 | state->x.have = 0; | |
400 | state->eof = 0; | |
401 | state->past = 0; | |
402 | state->seek = 0; | |
403 | gz_error(state, Z_OK, NULL); | |
404 | state->strm.avail_in = 0; | |
405 | state->x.pos += offset; | |
406 | return state->x.pos; | |
407 | } | |
408 | ||
409 | /* calculate skip amount, rewinding if needed for back seek when reading */ | |
410 | if (offset < 0) { | |
411 | if (state->mode != GZ_READ) /* writing -- can't go backwards */ | |
412 | return -1; | |
413 | offset += state->x.pos; | |
414 | if (offset < 0) /* before start of file! */ | |
415 | return -1; | |
416 | if (gzrewind(file) == -1) /* rewind, then skip to offset */ | |
417 | return -1; | |
418 | } | |
419 | ||
420 | /* if reading, skip what's in output buffer (one less gzgetc() check) */ | |
421 | if (state->mode == GZ_READ) { | |
422 | n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > offset ? | |
423 | (unsigned)offset : state->x.have; | |
424 | state->x.have -= n; | |
425 | state->x.next += n; | |
426 | state->x.pos += n; | |
427 | offset -= n; | |
428 | } | |
429 | ||
430 | /* request skip (if not zero) */ | |
431 | if (offset) { | |
432 | state->seek = 1; | |
433 | state->skip = offset; | |
434 | } | |
435 | return state->x.pos + offset; | |
436 | } | |
437 | ||
438 | /* -- see zlib.h -- */ | |
439 | z_off_t ZEXPORT gzseek(file, offset, whence) | |
440 | gzFile file; | |
441 | z_off_t offset; | |
442 | int whence; | |
443 | { | |
444 | z_off64_t ret; | |
445 | ||
446 | ret = gzseek64(file, (z_off64_t)offset, whence); | |
447 | return ret == (z_off_t)ret ? (z_off_t)ret : -1; | |
448 | } | |
449 | ||
450 | /* -- see zlib.h -- */ | |
451 | z_off64_t ZEXPORT gztell64(file) | |
452 | gzFile file; | |
453 | { | |
454 | gz_statep state; | |
455 | ||
456 | /* get internal structure and check integrity */ | |
457 | if (file == NULL) | |
458 | return -1; | |
459 | state = (gz_statep)file; | |
460 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
461 | return -1; | |
462 | ||
463 | /* return position */ | |
464 | return state->x.pos + (state->seek ? state->skip : 0); | |
465 | } | |
466 | ||
467 | /* -- see zlib.h -- */ | |
468 | z_off_t ZEXPORT gztell(file) | |
469 | gzFile file; | |
470 | { | |
471 | z_off64_t ret; | |
472 | ||
473 | ret = gztell64(file); | |
474 | return ret == (z_off_t)ret ? (z_off_t)ret : -1; | |
475 | } | |
476 | ||
477 | /* -- see zlib.h -- */ | |
478 | z_off64_t ZEXPORT gzoffset64(file) | |
479 | gzFile file; | |
480 | { | |
481 | z_off64_t offset; | |
482 | gz_statep state; | |
483 | ||
484 | /* get internal structure and check integrity */ | |
485 | if (file == NULL) | |
486 | return -1; | |
487 | state = (gz_statep)file; | |
488 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
489 | return -1; | |
490 | ||
491 | /* compute and return effective offset in file */ | |
492 | offset = LSEEK(state->fd, 0, SEEK_CUR); | |
493 | if (offset == -1) | |
494 | return -1; | |
495 | if (state->mode == GZ_READ) /* reading */ | |
496 | offset -= state->strm.avail_in; /* don't count buffered input */ | |
497 | return offset; | |
498 | } | |
499 | ||
500 | /* -- see zlib.h -- */ | |
501 | z_off_t ZEXPORT gzoffset(file) | |
502 | gzFile file; | |
503 | { | |
504 | z_off64_t ret; | |
505 | ||
506 | ret = gzoffset64(file); | |
507 | return ret == (z_off_t)ret ? (z_off_t)ret : -1; | |
508 | } | |
509 | ||
510 | /* -- see zlib.h -- */ | |
511 | int ZEXPORT gzeof(file) | |
512 | gzFile file; | |
513 | { | |
514 | gz_statep state; | |
515 | ||
516 | /* get internal structure and check integrity */ | |
517 | if (file == NULL) | |
518 | return 0; | |
519 | state = (gz_statep)file; | |
520 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
521 | return 0; | |
522 | ||
523 | /* return end-of-file state */ | |
524 | return state->mode == GZ_READ ? state->past : 0; | |
525 | } | |
526 | ||
527 | /* -- see zlib.h -- */ | |
528 | const char * ZEXPORT gzerror(file, errnum) | |
529 | gzFile file; | |
530 | int *errnum; | |
531 | { | |
532 | gz_statep state; | |
533 | ||
534 | /* get internal structure and check integrity */ | |
535 | if (file == NULL) | |
536 | return NULL; | |
537 | state = (gz_statep)file; | |
538 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
539 | return NULL; | |
540 | ||
541 | /* return error information */ | |
542 | if (errnum != NULL) | |
543 | *errnum = state->err; | |
da09a436 JB |
544 | return state->err == Z_MEM_ERROR ? "out of memory" : |
545 | (state->msg == NULL ? "" : state->msg); | |
5ca28f79 L |
546 | } |
547 | ||
548 | /* -- see zlib.h -- */ | |
549 | void ZEXPORT gzclearerr(file) | |
550 | gzFile file; | |
551 | { | |
552 | gz_statep state; | |
553 | ||
554 | /* get internal structure and check integrity */ | |
555 | if (file == NULL) | |
556 | return; | |
557 | state = (gz_statep)file; | |
558 | if (state->mode != GZ_READ && state->mode != GZ_WRITE) | |
559 | return; | |
560 | ||
561 | /* clear error and end-of-file */ | |
562 | if (state->mode == GZ_READ) { | |
563 | state->eof = 0; | |
564 | state->past = 0; | |
565 | } | |
566 | gz_error(state, Z_OK, NULL); | |
567 | } | |
568 | ||
569 | /* Create an error message in allocated memory and set state->err and | |
570 | state->msg accordingly. Free any previous error message already there. Do | |
571 | not try to free or allocate space if the error is Z_MEM_ERROR (out of | |
572 | memory). Simply save the error message as a static string. If there is an | |
573 | allocation failure constructing the error message, then convert the error to | |
574 | out of memory. */ | |
575 | void ZLIB_INTERNAL gz_error(state, err, msg) | |
576 | gz_statep state; | |
577 | int err; | |
578 | const char *msg; | |
579 | { | |
580 | /* free previously allocated message and clear */ | |
581 | if (state->msg != NULL) { | |
582 | if (state->err != Z_MEM_ERROR) | |
583 | free(state->msg); | |
584 | state->msg = NULL; | |
585 | } | |
586 | ||
587 | /* if fatal, set state->x.have to 0 so that the gzgetc() macro fails */ | |
588 | if (err != Z_OK && err != Z_BUF_ERROR) | |
589 | state->x.have = 0; | |
590 | ||
591 | /* set error code, and if no message, then done */ | |
592 | state->err = err; | |
593 | if (msg == NULL) | |
594 | return; | |
595 | ||
da09a436 JB |
596 | /* for an out of memory error, return literal string when requested */ |
597 | if (err == Z_MEM_ERROR) | |
5ca28f79 | 598 | return; |
5ca28f79 L |
599 | |
600 | /* construct error message with path */ | |
da09a436 JB |
601 | if ((state->msg = (char *)malloc(strlen(state->path) + strlen(msg) + 3)) == |
602 | NULL) { | |
5ca28f79 | 603 | state->err = Z_MEM_ERROR; |
5ca28f79 L |
604 | return; |
605 | } | |
da09a436 JB |
606 | #if !defined(NO_snprintf) && !defined(NO_vsnprintf) |
607 | snprintf(state->msg, strlen(state->path) + strlen(msg) + 3, | |
608 | "%s%s%s", state->path, ": ", msg); | |
609 | #else | |
5ca28f79 L |
610 | strcpy(state->msg, state->path); |
611 | strcat(state->msg, ": "); | |
612 | strcat(state->msg, msg); | |
da09a436 | 613 | #endif |
5ca28f79 L |
614 | return; |
615 | } | |
616 | ||
617 | #ifndef INT_MAX | |
618 | /* portably return maximum value for an int (when limits.h presumed not | |
619 | available) -- we need to do this to cover cases where 2's complement not | |
620 | used, since C standard permits 1's complement and sign-bit representations, | |
621 | otherwise we could just use ((unsigned)-1) >> 1 */ | |
622 | unsigned ZLIB_INTERNAL gz_intmax() | |
623 | { | |
624 | unsigned p, q; | |
625 | ||
626 | p = 1; | |
627 | do { | |
628 | q = p; | |
629 | p <<= 1; | |
630 | p++; | |
631 | } while (p > q); | |
632 | return q >> 1; | |
633 | } | |
634 | #endif |