1 /* gzwrite.c -- zlib functions for writing gzip files
2 * Copyright (C) 2004-2017 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 /* $FreeBSD$ */
7
8 #include "gzguts.h"
9 #include <unistd.h>
10
11 /* Local functions */
12 local int gz_init OF((gz_statep));
13 local int gz_comp OF((gz_statep, int));
14 local int gz_zero OF((gz_statep, z_off64_t));
15 local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));
16
17 /* Initialize state for writing a gzip file. Mark initialization by setting
18 state->size to non-zero. Return -1 on a memory allocation failure, or 0 on
19 success. */
gz_init(state)20 local int gz_init(state)
21 gz_statep state;
22 {
23 int ret;
24 z_streamp strm = &(state->strm);
25
26 /* allocate input buffer (double size for gzprintf) */
27 state->in = (unsigned char *)malloc(state->want << 1);
28 if (state->in == NULL) {
29 gz_error(state, Z_MEM_ERROR, "out of memory");
30 return -1;
31 }
32
33 /* only need output buffer and deflate state if compressing */
34 if (!state->direct) {
35 /* allocate output buffer */
36 state->out = (unsigned char *)malloc(state->want);
37 if (state->out == NULL) {
38 free(state->in);
39 gz_error(state, Z_MEM_ERROR, "out of memory");
40 return -1;
41 }
42
43 /* allocate deflate memory, set up for gzip compression */
44 strm->zalloc = Z_NULL;
45 strm->zfree = Z_NULL;
46 strm->opaque = Z_NULL;
47 ret = deflateInit2(strm, state->level, Z_DEFLATED,
48 MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
49 if (ret != Z_OK) {
50 free(state->out);
51 free(state->in);
52 gz_error(state, Z_MEM_ERROR, "out of memory");
53 return -1;
54 }
55 strm->next_in = NULL;
56 }
57
58 /* mark state as initialized */
59 state->size = state->want;
60
61 /* initialize write buffer if compressing */
62 if (!state->direct) {
63 strm->avail_out = state->size;
64 strm->next_out = state->out;
65 state->x.next = strm->next_out;
66 }
67 return 0;
68 }
69
70 /* Compress whatever is at avail_in and next_in and write to the output file.
71 Return -1 if there is an error writing to the output file or if gz_init()
72 fails to allocate memory, otherwise 0. flush is assumed to be a valid
73 deflate() flush value. If flush is Z_FINISH, then the deflate() state is
74 reset to start a new gzip stream. If gz->direct is true, then simply write
75 to the output file without compressing, and ignore flush. */
gz_comp(state,flush)76 local int gz_comp(state, flush)
77 gz_statep state;
78 int flush;
79 {
80 int ret, writ;
81 unsigned have, put, max = ((unsigned)-1 >> 2) + 1;
82 z_streamp strm = &(state->strm);
83
84 /* allocate memory if this is the first time through */
85 if (state->size == 0 && gz_init(state) == -1)
86 return -1;
87
88 /* write directly if requested */
89 if (state->direct) {
90 while (strm->avail_in) {
91 put = strm->avail_in > max ? max : strm->avail_in;
92 writ = write(state->fd, strm->next_in, put);
93 if (writ < 0) {
94 gz_error(state, Z_ERRNO, zstrerror());
95 return -1;
96 }
97 strm->avail_in -= (unsigned)writ;
98 strm->next_in += writ;
99 }
100 return 0;
101 }
102
103 /* run deflate() on provided input until it produces no more output */
104 ret = Z_OK;
105 do {
106 /* write out current buffer contents if full, or if flushing, but if
107 doing Z_FINISH then don't write until we get to Z_STREAM_END */
108 if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
109 (flush != Z_FINISH || ret == Z_STREAM_END))) {
110 while (strm->next_out > state->x.next) {
111 put = strm->next_out - state->x.next > (int)max ? max :
112 (unsigned)(strm->next_out - state->x.next);
113 writ = write(state->fd, state->x.next, put);
114 if (writ < 0) {
115 gz_error(state, Z_ERRNO, zstrerror());
116 return -1;
117 }
118 state->x.next += writ;
119 }
120 if (strm->avail_out == 0) {
121 strm->avail_out = state->size;
122 strm->next_out = state->out;
123 state->x.next = state->out;
124 }
125 }
126
127 /* compress */
128 have = strm->avail_out;
129 ret = deflate(strm, flush);
130 if (ret == Z_STREAM_ERROR) {
131 gz_error(state, Z_STREAM_ERROR,
132 "internal error: deflate stream corrupt");
133 return -1;
134 }
135 have -= strm->avail_out;
136 } while (have);
137
138 /* if that completed a deflate stream, allow another to start */
139 if (flush == Z_FINISH)
140 deflateReset(strm);
141
142 /* all done, no errors */
143 return 0;
144 }
145
146 /* Compress len zeros to output. Return -1 on a write error or memory
147 allocation failure by gz_comp(), or 0 on success. */
gz_zero(state,len)148 local int gz_zero(state, len)
149 gz_statep state;
150 z_off64_t len;
151 {
152 int first;
153 unsigned n;
154 z_streamp strm = &(state->strm);
155
156 /* consume whatever's left in the input buffer */
157 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
158 return -1;
159
160 /* compress len zeros (len guaranteed > 0) */
161 first = 1;
162 while (len) {
163 n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
164 (unsigned)len : state->size;
165 if (first) {
166 memset(state->in, 0, n);
167 first = 0;
168 }
169 strm->avail_in = n;
170 strm->next_in = state->in;
171 state->x.pos += n;
172 if (gz_comp(state, Z_NO_FLUSH) == -1)
173 return -1;
174 len -= n;
175 }
176 return 0;
177 }
178
179 /* Write len bytes from buf to file. Return the number of bytes written. If
180 the returned value is less than len, then there was an error. */
gz_write(state,buf,len)181 local z_size_t gz_write(state, buf, len)
182 gz_statep state;
183 voidpc buf;
184 z_size_t len;
185 {
186 z_size_t put = len;
187
188 /* if len is zero, avoid unnecessary operations */
189 if (len == 0)
190 return 0;
191
192 /* allocate memory if this is the first time through */
193 if (state->size == 0 && gz_init(state) == -1)
194 return 0;
195
196 /* check for seek request */
197 if (state->seek) {
198 state->seek = 0;
199 if (gz_zero(state, state->skip) == -1)
200 return 0;
201 }
202
203 /* for small len, copy to input buffer, otherwise compress directly */
204 if (len < state->size) {
205 /* copy to input buffer, compress when full */
206 do {
207 unsigned have, copy;
208
209 if (state->strm.avail_in == 0)
210 state->strm.next_in = state->in;
211 have = (unsigned)((state->strm.next_in + state->strm.avail_in) -
212 state->in);
213 copy = state->size - have;
214 if (copy > len)
215 copy = len;
216 memcpy(state->in + have, buf, copy);
217 state->strm.avail_in += copy;
218 state->x.pos += copy;
219 buf = (const char *)buf + copy;
220 len -= copy;
221 if (len && gz_comp(state, Z_NO_FLUSH) == -1)
222 return 0;
223 } while (len);
224 }
225 else {
226 /* consume whatever's left in the input buffer */
227 if (state->strm.avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
228 return 0;
229
230 /* directly compress user buffer to file */
231 state->strm.next_in = (z_const Bytef *)buf;
232 do {
233 unsigned n = (unsigned)-1;
234 if (n > len)
235 n = len;
236 state->strm.avail_in = n;
237 state->x.pos += n;
238 if (gz_comp(state, Z_NO_FLUSH) == -1)
239 return 0;
240 len -= n;
241 } while (len);
242 }
243
244 /* input was all buffered or compressed */
245 return put;
246 }
247
248 /* -- see zlib.h -- */
gzwrite(file,buf,len)249 int ZEXPORT gzwrite(file, buf, len)
250 gzFile file;
251 voidpc buf;
252 unsigned len;
253 {
254 gz_statep state;
255
256 /* get internal structure */
257 if (file == NULL)
258 return 0;
259 state = (gz_statep)file;
260
261 /* check that we're writing and that there's no error */
262 if (state->mode != GZ_WRITE || state->err != Z_OK)
263 return 0;
264
265 /* since an int is returned, make sure len fits in one, otherwise return
266 with an error (this avoids a flaw in the interface) */
267 if ((int)len < 0) {
268 gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
269 return 0;
270 }
271
272 /* write len bytes from buf (the return value will fit in an int) */
273 return (int)gz_write(state, buf, len);
274 }
275
276 /* -- see zlib.h -- */
gzfwrite(buf,size,nitems,file)277 z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
278 voidpc buf;
279 z_size_t size;
280 z_size_t nitems;
281 gzFile file;
282 {
283 z_size_t len;
284 gz_statep state;
285
286 /* get internal structure */
287 if (file == NULL)
288 return 0;
289 state = (gz_statep)file;
290
291 /* check that we're writing and that there's no error */
292 if (state->mode != GZ_WRITE || state->err != Z_OK)
293 return 0;
294
295 /* compute bytes to read -- error on overflow */
296 len = nitems * size;
297 if (size && len / size != nitems) {
298 gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
299 return 0;
300 }
301
302 /* write len bytes to buf, return the number of full items written */
303 return len ? gz_write(state, buf, len) / size : 0;
304 }
305
306 /* -- see zlib.h -- */
gzputc(file,c)307 int ZEXPORT gzputc(file, c)
308 gzFile file;
309 int c;
310 {
311 unsigned have;
312 unsigned char buf[1];
313 gz_statep state;
314 z_streamp strm;
315
316 /* get internal structure */
317 if (file == NULL)
318 return -1;
319 state = (gz_statep)file;
320 strm = &(state->strm);
321
322 /* check that we're writing and that there's no error */
323 if (state->mode != GZ_WRITE || state->err != Z_OK)
324 return -1;
325
326 /* check for seek request */
327 if (state->seek) {
328 state->seek = 0;
329 if (gz_zero(state, state->skip) == -1)
330 return -1;
331 }
332
333 /* try writing to input buffer for speed (state->size == 0 if buffer not
334 initialized) */
335 if (state->size) {
336 if (strm->avail_in == 0)
337 strm->next_in = state->in;
338 have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
339 if (have < state->size) {
340 state->in[have] = (unsigned char)c;
341 strm->avail_in++;
342 state->x.pos++;
343 return c & 0xff;
344 }
345 }
346
347 /* no room in buffer or not initialized, use gz_write() */
348 buf[0] = (unsigned char)c;
349 if (gz_write(state, buf, 1) != 1)
350 return -1;
351 return c & 0xff;
352 }
353
354 /* -- see zlib.h -- */
gzputs(file,str)355 int ZEXPORT gzputs(file, str)
356 gzFile file;
357 const char *str;
358 {
359 int ret;
360 z_size_t len;
361 gz_statep state;
362
363 /* get internal structure */
364 if (file == NULL)
365 return -1;
366 state = (gz_statep)file;
367
368 /* check that we're writing and that there's no error */
369 if (state->mode != GZ_WRITE || state->err != Z_OK)
370 return -1;
371
372 /* write string */
373 len = strlen(str);
374 ret = gz_write(state, str, len);
375 return ret == 0 && len != 0 ? -1 : ret;
376 }
377
378 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
379 #include <stdarg.h>
380
381 /* -- see zlib.h -- */
gzvprintf(gzFile file,const char * format,va_list va)382 int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
383 {
384 int len;
385 unsigned left;
386 char *next;
387 gz_statep state;
388 z_streamp strm;
389
390 /* get internal structure */
391 if (file == NULL)
392 return Z_STREAM_ERROR;
393 state = (gz_statep)file;
394 strm = &(state->strm);
395
396 /* check that we're writing and that there's no error */
397 if (state->mode != GZ_WRITE || state->err != Z_OK)
398 return Z_STREAM_ERROR;
399
400 /* make sure we have some buffer space */
401 if (state->size == 0 && gz_init(state) == -1)
402 return state->err;
403
404 /* check for seek request */
405 if (state->seek) {
406 state->seek = 0;
407 if (gz_zero(state, state->skip) == -1)
408 return state->err;
409 }
410
411 /* do the printf() into the input buffer, put length in len -- the input
412 buffer is double-sized just for this function, so there is guaranteed to
413 be state->size bytes available after the current contents */
414 if (strm->avail_in == 0)
415 strm->next_in = state->in;
416 next = (char *)(state->in + (strm->next_in - state->in) + strm->avail_in);
417 next[state->size - 1] = 0;
418 #ifdef NO_vsnprintf
419 # ifdef HAS_vsprintf_void
420 (void)vsprintf(next, format, va);
421 for (len = 0; len < state->size; len++)
422 if (next[len] == 0) break;
423 # else
424 len = vsprintf(next, format, va);
425 # endif
426 #else
427 # ifdef HAS_vsnprintf_void
428 (void)vsnprintf(next, state->size, format, va);
429 len = strlen(next);
430 # else
431 len = vsnprintf(next, state->size, format, va);
432 # endif
433 #endif
434
435 /* check that printf() results fit in buffer */
436 if (len == 0 || (unsigned)len >= state->size || next[state->size - 1] != 0)
437 return 0;
438
439 /* update buffer and position, compress first half if past that */
440 strm->avail_in += (unsigned)len;
441 state->x.pos += len;
442 if (strm->avail_in >= state->size) {
443 left = strm->avail_in - state->size;
444 strm->avail_in = state->size;
445 if (gz_comp(state, Z_NO_FLUSH) == -1)
446 return state->err;
447 memcpy(state->in, state->in + state->size, left);
448 strm->next_in = state->in;
449 strm->avail_in = left;
450 }
451 return len;
452 }
453
gzprintf(gzFile file,const char * format,...)454 int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
455 {
456 va_list va;
457 int ret;
458
459 va_start(va, format);
460 ret = gzvprintf(file, format, va);
461 va_end(va);
462 return ret;
463 }
464
465 #else /* !STDC && !Z_HAVE_STDARG_H */
466
467 /* -- see zlib.h -- */
gzprintf(file,format,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)468 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
469 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
470 gzFile file;
471 const char *format;
472 int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
473 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
474 {
475 unsigned len, left;
476 char *next;
477 gz_statep state;
478 z_streamp strm;
479
480 /* get internal structure */
481 if (file == NULL)
482 return Z_STREAM_ERROR;
483 state = (gz_statep)file;
484 strm = &(state->strm);
485
486 /* check that can really pass pointer in ints */
487 if (sizeof(int) != sizeof(void *))
488 return Z_STREAM_ERROR;
489
490 /* check that we're writing and that there's no error */
491 if (state->mode != GZ_WRITE || state->err != Z_OK)
492 return Z_STREAM_ERROR;
493
494 /* make sure we have some buffer space */
495 if (state->size == 0 && gz_init(state) == -1)
496 return state->error;
497
498 /* check for seek request */
499 if (state->seek) {
500 state->seek = 0;
501 if (gz_zero(state, state->skip) == -1)
502 return state->error;
503 }
504
505 /* do the printf() into the input buffer, put length in len -- the input
506 buffer is double-sized just for this function, so there is guaranteed to
507 be state->size bytes available after the current contents */
508 if (strm->avail_in == 0)
509 strm->next_in = state->in;
510 next = (char *)(strm->next_in + strm->avail_in);
511 next[state->size - 1] = 0;
512 #ifdef NO_snprintf
513 # ifdef HAS_sprintf_void
514 sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
515 a13, a14, a15, a16, a17, a18, a19, a20);
516 for (len = 0; len < size; len++)
517 if (next[len] == 0)
518 break;
519 # else
520 len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
521 a12, a13, a14, a15, a16, a17, a18, a19, a20);
522 # endif
523 #else
524 # ifdef HAS_snprintf_void
525 snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
526 a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
527 len = strlen(next);
528 # else
529 len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8,
530 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
531 # endif
532 #endif
533
534 /* check that printf() results fit in buffer */
535 if (len == 0 || len >= state->size || next[state->size - 1] != 0)
536 return 0;
537
538 /* update buffer and position, compress first half if past that */
539 strm->avail_in += len;
540 state->x.pos += len;
541 if (strm->avail_in >= state->size) {
542 left = strm->avail_in - state->size;
543 strm->avail_in = state->size;
544 if (gz_comp(state, Z_NO_FLUSH) == -1)
545 return state->err;
546 memcpy(state->in, state->in + state->size, left);
547 strm->next_in = state->in;
548 strm->avail_in = left;
549 }
550 return (int)len;
551 }
552
553 #endif
554
555 /* -- see zlib.h -- */
gzflush(file,flush)556 int ZEXPORT gzflush(file, flush)
557 gzFile file;
558 int flush;
559 {
560 gz_statep state;
561
562 /* get internal structure */
563 if (file == NULL)
564 return Z_STREAM_ERROR;
565 state = (gz_statep)file;
566
567 /* check that we're writing and that there's no error */
568 if (state->mode != GZ_WRITE || state->err != Z_OK)
569 return Z_STREAM_ERROR;
570
571 /* check flush parameter */
572 if (flush < 0 || flush > Z_FINISH)
573 return Z_STREAM_ERROR;
574
575 /* check for seek request */
576 if (state->seek) {
577 state->seek = 0;
578 if (gz_zero(state, state->skip) == -1)
579 return state->err;
580 }
581
582 /* compress remaining data with requested flush */
583 (void)gz_comp(state, flush);
584 return state->err;
585 }
586
587 /* -- see zlib.h -- */
gzsetparams(file,level,strategy)588 int ZEXPORT gzsetparams(file, level, strategy)
589 gzFile file;
590 int level;
591 int strategy;
592 {
593 gz_statep state;
594 z_streamp strm;
595
596 /* get internal structure */
597 if (file == NULL)
598 return Z_STREAM_ERROR;
599 state = (gz_statep)file;
600 strm = &(state->strm);
601
602 /* check that we're writing and that there's no error */
603 if (state->mode != GZ_WRITE || state->err != Z_OK)
604 return Z_STREAM_ERROR;
605
606 /* if no change is requested, then do nothing */
607 if (level == state->level && strategy == state->strategy)
608 return Z_OK;
609
610 /* check for seek request */
611 if (state->seek) {
612 state->seek = 0;
613 if (gz_zero(state, state->skip) == -1)
614 return state->err;
615 }
616
617 /* change compression parameters for subsequent input */
618 if (state->size) {
619 /* flush previous input with previous parameters before changing */
620 if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
621 return state->err;
622 deflateParams(strm, level, strategy);
623 }
624 state->level = level;
625 state->strategy = strategy;
626 return Z_OK;
627 }
628
629 /* -- see zlib.h -- */
gzclose_w(file)630 int ZEXPORT gzclose_w(file)
631 gzFile file;
632 {
633 int ret = Z_OK;
634 gz_statep state;
635
636 /* get internal structure */
637 if (file == NULL)
638 return Z_STREAM_ERROR;
639 state = (gz_statep)file;
640
641 /* check that we're writing */
642 if (state->mode != GZ_WRITE)
643 return Z_STREAM_ERROR;
644
645 /* check for seek request */
646 if (state->seek) {
647 state->seek = 0;
648 if (gz_zero(state, state->skip) == -1)
649 ret = state->err;
650 }
651
652 /* flush, free memory, and close file */
653 if (gz_comp(state, Z_FINISH) == -1)
654 ret = state->err;
655 if (state->size) {
656 if (!state->direct) {
657 (void)deflateEnd(&(state->strm));
658 free(state->out);
659 }
660 free(state->in);
661 }
662 gz_error(state, Z_OK, NULL);
663 free(state->path);
664 if (close(state->fd) == -1)
665 ret = Z_ERRNO;
666 free(state);
667 return ret;
668 }
669