1 /* gzwrite.c -- zlib functions for writing gzip files
2 * Copyright (C) 2004-2019 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 #include "gzguts.h"
7
8 /* Local functions */
9 local int gz_init OF((gz_statep));
10 local int gz_comp OF((gz_statep, int));
11 local int gz_zero OF((gz_statep, z_off64_t));
12 local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));
13
14 /* Initialize state for writing a gzip file. Mark initialization by setting
15 state->size to non-zero. Return -1 on a memory allocation failure, or 0 on
16 success. */
17 local int gz_init(state)
18 gz_statep state;
19 {
20 int ret;
21 z_streamp strm = &(state->strm);
22
23 /* allocate input buffer (double size for gzprintf) */
24 state->in = (unsigned char *)malloc(state->want << 1);
25 if (state->in == NULL) {
26 gz_error(state, Z_MEM_ERROR, "out of memory");
27 return -1;
28 }
29
30 /* only need output buffer and deflate state if compressing */
31 if (!state->direct) {
32 /* allocate output buffer */
33 state->out = (unsigned char *)malloc(state->want);
34 if (state->out == NULL) {
35 free(state->in);
36 gz_error(state, Z_MEM_ERROR, "out of memory");
37 return -1;
38 }
39
40 /* allocate deflate memory, set up for gzip compression */
41 strm->zalloc = Z_NULL;
42 strm->zfree = Z_NULL;
43 strm->opaque = Z_NULL;
44 ret = deflateInit2(strm, state->level, Z_DEFLATED,
45 MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
46 if (ret != Z_OK) {
47 free(state->out);
48 free(state->in);
49 gz_error(state, Z_MEM_ERROR, "out of memory");
50 return -1;
51 }
52 strm->next_in = NULL;
53 }
54
55 /* mark state as initialized */
56 state->size = state->want;
57
58 /* initialize write buffer if compressing */
59 if (!state->direct) {
60 strm->avail_out = state->size;
61 strm->next_out = state->out;
62 state->x.next = strm->next_out;
63 }
64 return 0;
65 }
66
67 /* Compress whatever is at avail_in and next_in and write to the output file.
68 Return -1 if there is an error writing to the output file or if gz_init()
69 fails to allocate memory, otherwise 0. flush is assumed to be a valid
70 deflate() flush value. If flush is Z_FINISH, then the deflate() state is
71 reset to start a new gzip stream. If gz->direct is true, then simply write
72 to the output file without compressing, and ignore flush. */
73 local int gz_comp(state, flush)
74 gz_statep state;
75 int flush;
76 {
77 int ret, writ;
78 unsigned have, put, max = ((unsigned)-1 >> 2) + 1;
79 z_streamp strm = &(state->strm);
80
81 /* allocate memory if this is the first time through */
82 if (state->size == 0 && gz_init(state) == -1)
83 return -1;
84
85 /* write directly if requested */
86 if (state->direct) {
87 while (strm->avail_in) {
88 put = strm->avail_in > max ? max : strm->avail_in;
89 writ = write(state->fd, strm->next_in, put);
90 if (writ < 0) {
91 gz_error(state, Z_ERRNO, zstrerror());
92 return -1;
93 }
94 strm->avail_in -= (unsigned)writ;
95 strm->next_in += writ;
96 }
97 return 0;
98 }
99
100 /* check for a pending reset */
101 if (state->reset) {
102 /* don't start a new gzip member unless there is data to write */
103 if (strm->avail_in == 0)
104 return 0;
105 deflateReset(strm);
106 state->reset = 0;
107 }
108
109 /* run deflate() on provided input until it produces no more output */
110 ret = Z_OK;
111 do {
112 /* write out current buffer contents if full, or if flushing, but if
113 doing Z_FINISH then don't write until we get to Z_STREAM_END */
114 if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
115 (flush != Z_FINISH || ret == Z_STREAM_END))) {
116 while (strm->next_out > state->x.next) {
117 put = strm->next_out - state->x.next > (int)max ? max :
118 (unsigned)(strm->next_out - state->x.next);
119 writ = write(state->fd, state->x.next, put);
120 if (writ < 0) {
121 gz_error(state, Z_ERRNO, zstrerror());
122 return -1;
123 }
124 state->x.next += writ;
125 }
126 if (strm->avail_out == 0) {
127 strm->avail_out = state->size;
128 strm->next_out = state->out;
129 state->x.next = state->out;
130 }
131 }
132
133 /* compress */
134 have = strm->avail_out;
135 ret = deflate(strm, flush);
136 if (ret == Z_STREAM_ERROR) {
137 gz_error(state, Z_STREAM_ERROR,
138 "internal error: deflate stream corrupt");
139 return -1;
140 }
141 have -= strm->avail_out;
142 } while (have);
143
144 /* if that completed a deflate stream, allow another to start */
145 if (flush == Z_FINISH)
146 state->reset = 1;
147
148 /* all done, no errors */
149 return 0;
150 }
151
152 /* Compress len zeros to output. Return -1 on a write error or memory
153 allocation failure by gz_comp(), or 0 on success. */
154 local int gz_zero(state, len)
155 gz_statep state;
156 z_off64_t len;
157 {
158 int first;
159 unsigned n;
160 z_streamp strm = &(state->strm);
161
162 /* consume whatever's left in the input buffer */
163 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
164 return -1;
165
166 /* compress len zeros (len guaranteed > 0) */
167 first = 1;
168 while (len) {
169 n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
170 (unsigned)len : state->size;
171 if (first) {
172 memset(state->in, 0, n);
173 first = 0;
174 }
175 strm->avail_in = n;
176 strm->next_in = state->in;
177 state->x.pos += n;
178 if (gz_comp(state, Z_NO_FLUSH) == -1)
179 return -1;
180 len -= n;
181 }
182 return 0;
183 }
184
185 /* Write len bytes from buf to file. Return the number of bytes written. If
186 the returned value is less than len, then there was an error. */
187 local z_size_t gz_write(state, buf, len)
188 gz_statep state;
189 voidpc buf;
190 z_size_t len;
191 {
192 z_size_t put = len;
193
194 /* if len is zero, avoid unnecessary operations */
195 if (len == 0)
196 return 0;
197
198 /* allocate memory if this is the first time through */
199 if (state->size == 0 && gz_init(state) == -1)
200 return 0;
201
202 /* check for seek request */
203 if (state->seek) {
204 state->seek = 0;
205 if (gz_zero(state, state->skip) == -1)
206 return 0;
207 }
208
209 /* for small len, copy to input buffer, otherwise compress directly */
210 if (len < state->size) {
211 /* copy to input buffer, compress when full */
212 do {
213 unsigned have, copy;
214
215 if (state->strm.avail_in == 0)
216 state->strm.next_in = state->in;
217 have = (unsigned)((state->strm.next_in + state->strm.avail_in) -
218 state->in);
219 copy = state->size - have;
220 if (copy > len)
221 copy = (unsigned)len;
222 memcpy(state->in + have, buf, copy);
223 state->strm.avail_in += copy;
224 state->x.pos += copy;
225 buf = (const char *)buf + copy;
226 len -= copy;
227 if (len && gz_comp(state, Z_NO_FLUSH) == -1)
228 return 0;
229 } while (len);
230 }
231 else {
232 /* consume whatever's left in the input buffer */
233 if (state->strm.avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
234 return 0;
235
236 /* directly compress user buffer to file */
237 state->strm.next_in = (z_const Bytef *)buf;
238 do {
239 unsigned n = (unsigned)-1;
240 if (n > len)
241 n = (unsigned)len;
242 state->strm.avail_in = n;
243 state->x.pos += n;
244 if (gz_comp(state, Z_NO_FLUSH) == -1)
245 return 0;
246 len -= n;
247 } while (len);
248 }
249
250 /* input was all buffered or compressed */
251 return put;
252 }
253
254 /* -- see zlib.h -- */
255 int ZEXPORT gzwrite(file, buf, len)
256 gzFile file;
257 voidpc buf;
258 unsigned len;
259 {
260 gz_statep state;
261
262 /* get internal structure */
263 if (file == NULL)
264 return 0;
265 state = (gz_statep)file;
266
267 /* check that we're writing and that there's no error */
268 if (state->mode != GZ_WRITE || state->err != Z_OK)
269 return 0;
270
271 /* since an int is returned, make sure len fits in one, otherwise return
272 with an error (this avoids a flaw in the interface) */
273 if ((int)len < 0) {
274 gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
275 return 0;
276 }
277
278 /* write len bytes from buf (the return value will fit in an int) */
279 return (int)gz_write(state, buf, len);
280 }
281
282 /* -- see zlib.h -- */
283 z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
284 voidpc buf;
285 z_size_t size;
286 z_size_t nitems;
287 gzFile file;
288 {
289 z_size_t len;
290 gz_statep state;
291
292 /* get internal structure */
293 if (file == NULL)
294 return 0;
295 state = (gz_statep)file;
296
297 /* check that we're writing and that there's no error */
298 if (state->mode != GZ_WRITE || state->err != Z_OK)
299 return 0;
300
301 /* compute bytes to read -- error on overflow */
302 len = nitems * size;
303 if (size && len / size != nitems) {
304 gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
305 return 0;
306 }
307
308 /* write len bytes to buf, return the number of full items written */
309 return len ? gz_write(state, buf, len) / size : 0;
310 }
311
312 /* -- see zlib.h -- */
313 int ZEXPORT gzputc(file, c)
314 gzFile file;
315 int c;
316 {
317 unsigned have;
318 unsigned char buf[1];
319 gz_statep state;
320 z_streamp strm;
321
322 /* get internal structure */
323 if (file == NULL)
324 return -1;
325 state = (gz_statep)file;
326 strm = &(state->strm);
327
328 /* check that we're writing and that there's no error */
329 if (state->mode != GZ_WRITE || state->err != Z_OK)
330 return -1;
331
332 /* check for seek request */
333 if (state->seek) {
334 state->seek = 0;
335 if (gz_zero(state, state->skip) == -1)
336 return -1;
337 }
338
339 /* try writing to input buffer for speed (state->size == 0 if buffer not
340 initialized) */
341 if (state->size) {
342 if (strm->avail_in == 0)
343 strm->next_in = state->in;
344 have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
345 if (have < state->size) {
346 state->in[have] = (unsigned char)c;
347 strm->avail_in++;
348 state->x.pos++;
349 return c & 0xff;
350 }
351 }
352
353 /* no room in buffer or not initialized, use gz_write() */
354 buf[0] = (unsigned char)c;
355 if (gz_write(state, buf, 1) != 1)
356 return -1;
357 return c & 0xff;
358 }
359
360 /* -- see zlib.h -- */
361 int ZEXPORT gzputs(file, s)
362 gzFile file;
363 const char *s;
364 {
365 z_size_t len, put;
366 gz_statep state;
367
368 /* get internal structure */
369 if (file == NULL)
370 return -1;
371 state = (gz_statep)file;
372
373 /* check that we're writing and that there's no error */
374 if (state->mode != GZ_WRITE || state->err != Z_OK)
375 return -1;
376
377 /* write string */
378 len = strlen(s);
379 if ((int)len < 0 || (unsigned)len != len) {
380 gz_error(state, Z_STREAM_ERROR, "string length does not fit in int");
381 return -1;
382 }
383 put = gz_write(state, s, len);
384 return put < len ? -1 : (int)len;
385 }
386
387 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
388 #include <stdarg.h>
389
390 /* -- see zlib.h -- */
391 int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
392 {
393 int len;
394 unsigned left;
395 char *next;
396 gz_statep state;
397 z_streamp strm;
398
399 /* get internal structure */
400 if (file == NULL)
401 return Z_STREAM_ERROR;
402 state = (gz_statep)file;
403 strm = &(state->strm);
404
405 /* check that we're writing and that there's no error */
406 if (state->mode != GZ_WRITE || state->err != Z_OK)
407 return Z_STREAM_ERROR;
408
409 /* make sure we have some buffer space */
410 if (state->size == 0 && gz_init(state) == -1)
411 return state->err;
412
413 /* check for seek request */
414 if (state->seek) {
415 state->seek = 0;
416 if (gz_zero(state, state->skip) == -1)
417 return state->err;
418 }
419
420 /* do the printf() into the input buffer, put length in len -- the input
421 buffer is double-sized just for this function, so there is guaranteed to
422 be state->size bytes available after the current contents */
423 if (strm->avail_in == 0)
424 strm->next_in = state->in;
425 next = (char *)(state->in + (strm->next_in - state->in) + strm->avail_in);
426 next[state->size - 1] = 0;
427 #ifdef NO_vsnprintf
428 # ifdef HAS_vsprintf_void
429 (void)vsprintf(next, format, va);
430 for (len = 0; len < state->size; len++)
431 if (next[len] == 0) break;
432 # else
433 len = vsprintf(next, format, va);
434 # endif
435 #else
436 # ifdef HAS_vsnprintf_void
437 (void)vsnprintf(next, state->size, format, va);
438 len = strlen(next);
439 # else
440 len = vsnprintf(next, state->size, format, va);
441 # endif
442 #endif
443
444 /* check that printf() results fit in buffer */
445 if (len == 0 || (unsigned)len >= state->size || next[state->size - 1] != 0)
446 return 0;
447
448 /* update buffer and position, compress first half if past that */
449 strm->avail_in += (unsigned)len;
450 state->x.pos += len;
451 if (strm->avail_in >= state->size) {
452 left = strm->avail_in - state->size;
453 strm->avail_in = state->size;
454 if (gz_comp(state, Z_NO_FLUSH) == -1)
455 return state->err;
456 memmove(state->in, state->in + state->size, left);
457 strm->next_in = state->in;
458 strm->avail_in = left;
459 }
460 return len;
461 }
462
463 int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
464 {
465 va_list va;
466 int ret;
467
468 va_start(va, format);
469 ret = gzvprintf(file, format, va);
470 va_end(va);
471 return ret;
472 }
473
474 #else /* !STDC && !Z_HAVE_STDARG_H */
475
476 /* -- see zlib.h -- */
477 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
478 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
479 gzFile file;
480 const char *format;
481 int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
482 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
483 {
484 unsigned len, left;
485 char *next;
486 gz_statep state;
487 z_streamp strm;
488
489 /* get internal structure */
490 if (file == NULL)
491 return Z_STREAM_ERROR;
492 state = (gz_statep)file;
493 strm = &(state->strm);
494
495 /* check that can really pass pointer in ints */
496 if (sizeof(int) != sizeof(void *))
497 return Z_STREAM_ERROR;
498
499 /* check that we're writing and that there's no error */
500 if (state->mode != GZ_WRITE || state->err != Z_OK)
501 return Z_STREAM_ERROR;
502
503 /* make sure we have some buffer space */
504 if (state->size == 0 && gz_init(state) == -1)
505 return state->error;
506
507 /* check for seek request */
508 if (state->seek) {
509 state->seek = 0;
510 if (gz_zero(state, state->skip) == -1)
511 return state->error;
512 }
513
514 /* do the printf() into the input buffer, put length in len -- the input
515 buffer is double-sized just for this function, so there is guaranteed to
516 be state->size bytes available after the current contents */
517 if (strm->avail_in == 0)
518 strm->next_in = state->in;
519 next = (char *)(strm->next_in + strm->avail_in);
520 next[state->size - 1] = 0;
521 #ifdef NO_snprintf
522 # ifdef HAS_sprintf_void
523 sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
524 a13, a14, a15, a16, a17, a18, a19, a20);
525 for (len = 0; len < size; len++)
526 if (next[len] == 0)
527 break;
528 # else
529 len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
530 a12, a13, a14, a15, a16, a17, a18, a19, a20);
531 # endif
532 #else
533 # ifdef HAS_snprintf_void
534 snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
535 a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
536 len = strlen(next);
537 # else
538 len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8,
539 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
540 # endif
541 #endif
542
543 /* check that printf() results fit in buffer */
544 if (len == 0 || len >= state->size || next[state->size - 1] != 0)
545 return 0;
546
547 /* update buffer and position, compress first half if past that */
548 strm->avail_in += len;
549 state->x.pos += len;
550 if (strm->avail_in >= state->size) {
551 left = strm->avail_in - state->size;
552 strm->avail_in = state->size;
553 if (gz_comp(state, Z_NO_FLUSH) == -1)
554 return state->err;
555 memmove(state->in, state->in + state->size, left);
556 strm->next_in = state->in;
557 strm->avail_in = left;
558 }
559 return (int)len;
560 }
561
562 #endif
563
564 /* -- see zlib.h -- */
565 int ZEXPORT gzflush(file, flush)
566 gzFile file;
567 int flush;
568 {
569 gz_statep state;
570
571 /* get internal structure */
572 if (file == NULL)
573 return Z_STREAM_ERROR;
574 state = (gz_statep)file;
575
576 /* check that we're writing and that there's no error */
577 if (state->mode != GZ_WRITE || state->err != Z_OK)
578 return Z_STREAM_ERROR;
579
580 /* check flush parameter */
581 if (flush < 0 || flush > Z_FINISH)
582 return Z_STREAM_ERROR;
583
584 /* check for seek request */
585 if (state->seek) {
586 state->seek = 0;
587 if (gz_zero(state, state->skip) == -1)
588 return state->err;
589 }
590
591 /* compress remaining data with requested flush */
592 (void)gz_comp(state, flush);
593 return state->err;
594 }
595
596 /* -- see zlib.h -- */
597 int ZEXPORT gzsetparams(file, level, strategy)
598 gzFile file;
599 int level;
600 int strategy;
601 {
602 gz_statep state;
603 z_streamp strm;
604
605 /* get internal structure */
606 if (file == NULL)
607 return Z_STREAM_ERROR;
608 state = (gz_statep)file;
609 strm = &(state->strm);
610
611 /* check that we're writing and that there's no error */
612 if (state->mode != GZ_WRITE || state->err != Z_OK)
613 return Z_STREAM_ERROR;
614
615 /* if no change is requested, then do nothing */
616 if (level == state->level && strategy == state->strategy)
617 return Z_OK;
618
619 /* check for seek request */
620 if (state->seek) {
621 state->seek = 0;
622 if (gz_zero(state, state->skip) == -1)
623 return state->err;
624 }
625
626 /* change compression parameters for subsequent input */
627 if (state->size) {
628 /* flush previous input with previous parameters before changing */
629 if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
630 return state->err;
631 deflateParams(strm, level, strategy);
632 }
633 state->level = level;
634 state->strategy = strategy;
635 return Z_OK;
636 }
637
638 /* -- see zlib.h -- */
639 int ZEXPORT gzclose_w(file)
640 gzFile file;
641 {
642 int ret = Z_OK;
643 gz_statep state;
644
645 /* get internal structure */
646 if (file == NULL)
647 return Z_STREAM_ERROR;
648 state = (gz_statep)file;
649
650 /* check that we're writing */
651 if (state->mode != GZ_WRITE)
652 return Z_STREAM_ERROR;
653
654 /* check for seek request */
655 if (state->seek) {
656 state->seek = 0;
657 if (gz_zero(state, state->skip) == -1)
658 ret = state->err;
659 }
660
661 /* flush, free memory, and close file */
662 if (gz_comp(state, Z_FINISH) == -1)
663 ret = state->err;
664 if (state->size) {
665 if (!state->direct) {
666 (void)deflateEnd(&(state->strm));
667 free(state->out);
668 }
669 free(state->in);
670 }
671 gz_error(state, Z_OK, NULL);
672 free(state->path);
673 if (close(state->fd) == -1)
674 ret = Z_ERRNO;
675 free(state);
676 return ret;
677 }