Make url_fsize() return AVERROR(ENOSYS) rather than AVERROR(EPIPE) if
[libav.git] / libavformat / aviobuf.c
1 /*
2 * Buffered I/O for ffmpeg system
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg 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 GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "libavutil/crc.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "avio.h"
26 #include <stdarg.h>
27
28 #define IO_BUFFER_SIZE 32768
29
30 static void fill_buffer(ByteIOContext *s);
31 #if LIBAVFORMAT_VERSION_MAJOR >= 53
32 static int url_resetbuf(ByteIOContext *s, int flags);
33 #endif
34
35 int init_put_byte(ByteIOContext *s,
36 unsigned char *buffer,
37 int buffer_size,
38 int write_flag,
39 void *opaque,
40 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
41 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
42 int64_t (*seek)(void *opaque, int64_t offset, int whence))
43 {
44 s->buffer = buffer;
45 s->buffer_size = buffer_size;
46 s->buf_ptr = buffer;
47 s->opaque = opaque;
48 url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
49 s->write_packet = write_packet;
50 s->read_packet = read_packet;
51 s->seek = seek;
52 s->pos = 0;
53 s->must_flush = 0;
54 s->eof_reached = 0;
55 s->error = 0;
56 s->is_streamed = 0;
57 s->max_packet_size = 0;
58 s->update_checksum= NULL;
59 if(!read_packet && !write_flag){
60 s->pos = buffer_size;
61 s->buf_end = s->buffer + buffer_size;
62 }
63 s->read_pause = NULL;
64 s->read_seek = NULL;
65 return 0;
66 }
67
68 ByteIOContext *av_alloc_put_byte(
69 unsigned char *buffer,
70 int buffer_size,
71 int write_flag,
72 void *opaque,
73 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
74 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
75 int64_t (*seek)(void *opaque, int64_t offset, int whence))
76 {
77 ByteIOContext *s = av_mallocz(sizeof(ByteIOContext));
78 init_put_byte(s, buffer, buffer_size, write_flag, opaque,
79 read_packet, write_packet, seek);
80 return s;
81 }
82
83 static void flush_buffer(ByteIOContext *s)
84 {
85 if (s->buf_ptr > s->buffer) {
86 if (s->write_packet && !s->error){
87 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
88 if(ret < 0){
89 s->error = ret;
90 }
91 }
92 if(s->update_checksum){
93 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
94 s->checksum_ptr= s->buffer;
95 }
96 s->pos += s->buf_ptr - s->buffer;
97 }
98 s->buf_ptr = s->buffer;
99 }
100
101 void put_byte(ByteIOContext *s, int b)
102 {
103 *(s->buf_ptr)++ = b;
104 if (s->buf_ptr >= s->buf_end)
105 flush_buffer(s);
106 }
107
108 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
109 {
110 while (size > 0) {
111 int len = FFMIN(s->buf_end - s->buf_ptr, size);
112 memcpy(s->buf_ptr, buf, len);
113 s->buf_ptr += len;
114
115 if (s->buf_ptr >= s->buf_end)
116 flush_buffer(s);
117
118 buf += len;
119 size -= len;
120 }
121 }
122
123 void put_flush_packet(ByteIOContext *s)
124 {
125 flush_buffer(s);
126 s->must_flush = 0;
127 }
128
129 int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
130 {
131 int64_t offset1;
132 int64_t pos;
133 int force = whence & AVSEEK_FORCE;
134 whence &= ~AVSEEK_FORCE;
135
136 if(!s)
137 return AVERROR(EINVAL);
138
139 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
140
141 if (whence != SEEK_CUR && whence != SEEK_SET)
142 return AVERROR(EINVAL);
143
144 if (whence == SEEK_CUR) {
145 offset1 = pos + (s->buf_ptr - s->buffer);
146 if (offset == 0)
147 return offset1;
148 offset += offset1;
149 }
150 offset1 = offset - pos;
151 if (!s->must_flush &&
152 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
153 /* can do the seek inside the buffer */
154 s->buf_ptr = s->buffer + offset1;
155 } else if(s->is_streamed && !s->write_flag && offset1 >= 0 &&
156 (whence != SEEK_END || force)) {
157 while(s->pos < offset && !s->eof_reached)
158 fill_buffer(s);
159 if (s->eof_reached)
160 return AVERROR_EOF;
161 s->buf_ptr = s->buf_end + offset - s->pos;
162 } else {
163 int64_t res = AVERROR(EPIPE);
164
165 #if CONFIG_MUXERS || CONFIG_NETWORK
166 if (s->write_flag) {
167 flush_buffer(s);
168 s->must_flush = 1;
169 }
170 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
171 if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
172 return res;
173 if (!s->write_flag)
174 s->buf_end = s->buffer;
175 s->buf_ptr = s->buffer;
176 s->pos = offset;
177 }
178 s->eof_reached = 0;
179 return offset;
180 }
181
182 void url_fskip(ByteIOContext *s, int64_t offset)
183 {
184 url_fseek(s, offset, SEEK_CUR);
185 }
186
187 int64_t url_ftell(ByteIOContext *s)
188 {
189 return url_fseek(s, 0, SEEK_CUR);
190 }
191
192 int64_t url_fsize(ByteIOContext *s)
193 {
194 int64_t size;
195
196 if(!s)
197 return AVERROR(EINVAL);
198
199 if (!s->seek)
200 return AVERROR(ENOSYS);
201 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
202 if(size<0){
203 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
204 return size;
205 size++;
206 s->seek(s->opaque, s->pos, SEEK_SET);
207 }
208 return size;
209 }
210
211 int url_feof(ByteIOContext *s)
212 {
213 if(!s)
214 return 0;
215 return s->eof_reached;
216 }
217
218 int url_ferror(ByteIOContext *s)
219 {
220 if(!s)
221 return 0;
222 return s->error;
223 }
224
225 void put_le32(ByteIOContext *s, unsigned int val)
226 {
227 put_byte(s, val);
228 put_byte(s, val >> 8);
229 put_byte(s, val >> 16);
230 put_byte(s, val >> 24);
231 }
232
233 void put_be32(ByteIOContext *s, unsigned int val)
234 {
235 put_byte(s, val >> 24);
236 put_byte(s, val >> 16);
237 put_byte(s, val >> 8);
238 put_byte(s, val);
239 }
240
241 void put_strz(ByteIOContext *s, const char *str)
242 {
243 if (str)
244 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
245 else
246 put_byte(s, 0);
247 }
248
249 void put_le64(ByteIOContext *s, uint64_t val)
250 {
251 put_le32(s, (uint32_t)(val & 0xffffffff));
252 put_le32(s, (uint32_t)(val >> 32));
253 }
254
255 void put_be64(ByteIOContext *s, uint64_t val)
256 {
257 put_be32(s, (uint32_t)(val >> 32));
258 put_be32(s, (uint32_t)(val & 0xffffffff));
259 }
260
261 void put_le16(ByteIOContext *s, unsigned int val)
262 {
263 put_byte(s, val);
264 put_byte(s, val >> 8);
265 }
266
267 void put_be16(ByteIOContext *s, unsigned int val)
268 {
269 put_byte(s, val >> 8);
270 put_byte(s, val);
271 }
272
273 void put_le24(ByteIOContext *s, unsigned int val)
274 {
275 put_le16(s, val & 0xffff);
276 put_byte(s, val >> 16);
277 }
278
279 void put_be24(ByteIOContext *s, unsigned int val)
280 {
281 put_be16(s, val >> 8);
282 put_byte(s, val);
283 }
284
285 void put_tag(ByteIOContext *s, const char *tag)
286 {
287 while (*tag) {
288 put_byte(s, *tag++);
289 }
290 }
291
292 /* Input stream */
293
294 static void fill_buffer(ByteIOContext *s)
295 {
296 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
297 int len= s->buffer_size - (dst - s->buffer);
298 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
299
300 assert(s->buf_ptr == s->buf_end);
301
302 /* no need to do anything if EOF already reached */
303 if (s->eof_reached)
304 return;
305
306 if(s->update_checksum && dst == s->buffer){
307 if(s->buf_end > s->checksum_ptr)
308 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
309 s->checksum_ptr= s->buffer;
310 }
311
312 /* make buffer smaller in case it ended up large after probing */
313 if (s->buffer_size > max_buffer_size) {
314 url_setbufsize(s, max_buffer_size);
315
316 s->checksum_ptr = dst = s->buffer;
317 len = s->buffer_size;
318 }
319
320 if(s->read_packet)
321 len = s->read_packet(s->opaque, dst, len);
322 else
323 len = 0;
324 if (len <= 0) {
325 /* do not modify buffer if EOF reached so that a seek back can
326 be done without rereading data */
327 s->eof_reached = 1;
328 if(len<0)
329 s->error= len;
330 } else {
331 s->pos += len;
332 s->buf_ptr = dst;
333 s->buf_end = dst + len;
334 }
335 }
336
337 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
338 unsigned int len)
339 {
340 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
341 }
342
343 unsigned long get_checksum(ByteIOContext *s)
344 {
345 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
346 s->update_checksum= NULL;
347 return s->checksum;
348 }
349
350 void init_checksum(ByteIOContext *s,
351 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
352 unsigned long checksum)
353 {
354 s->update_checksum= update_checksum;
355 if(s->update_checksum){
356 s->checksum= checksum;
357 s->checksum_ptr= s->buf_ptr;
358 }
359 }
360
361 /* XXX: put an inline version */
362 int get_byte(ByteIOContext *s)
363 {
364 if (s->buf_ptr < s->buf_end) {
365 return *s->buf_ptr++;
366 } else {
367 fill_buffer(s);
368 if (s->buf_ptr < s->buf_end)
369 return *s->buf_ptr++;
370 else
371 return 0;
372 }
373 }
374
375 int url_fgetc(ByteIOContext *s)
376 {
377 if (s->buf_ptr < s->buf_end) {
378 return *s->buf_ptr++;
379 } else {
380 fill_buffer(s);
381 if (s->buf_ptr < s->buf_end)
382 return *s->buf_ptr++;
383 else
384 return URL_EOF;
385 }
386 }
387
388 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
389 {
390 int len, size1;
391
392 size1 = size;
393 while (size > 0) {
394 len = s->buf_end - s->buf_ptr;
395 if (len > size)
396 len = size;
397 if (len == 0) {
398 if(size > s->buffer_size && !s->update_checksum){
399 if(s->read_packet)
400 len = s->read_packet(s->opaque, buf, size);
401 if (len <= 0) {
402 /* do not modify buffer if EOF reached so that a seek back can
403 be done without rereading data */
404 s->eof_reached = 1;
405 if(len<0)
406 s->error= len;
407 break;
408 } else {
409 s->pos += len;
410 size -= len;
411 buf += len;
412 s->buf_ptr = s->buffer;
413 s->buf_end = s->buffer/* + len*/;
414 }
415 }else{
416 fill_buffer(s);
417 len = s->buf_end - s->buf_ptr;
418 if (len == 0)
419 break;
420 }
421 } else {
422 memcpy(buf, s->buf_ptr, len);
423 buf += len;
424 s->buf_ptr += len;
425 size -= len;
426 }
427 }
428 if (size1 == size) {
429 if (url_ferror(s)) return url_ferror(s);
430 if (url_feof(s)) return AVERROR_EOF;
431 }
432 return size1 - size;
433 }
434
435 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
436 {
437 int len;
438
439 if(size<0)
440 return -1;
441
442 len = s->buf_end - s->buf_ptr;
443 if (len == 0) {
444 fill_buffer(s);
445 len = s->buf_end - s->buf_ptr;
446 }
447 if (len > size)
448 len = size;
449 memcpy(buf, s->buf_ptr, len);
450 s->buf_ptr += len;
451 if (!len) {
452 if (url_ferror(s)) return url_ferror(s);
453 if (url_feof(s)) return AVERROR_EOF;
454 }
455 return len;
456 }
457
458 unsigned int get_le16(ByteIOContext *s)
459 {
460 unsigned int val;
461 val = get_byte(s);
462 val |= get_byte(s) << 8;
463 return val;
464 }
465
466 unsigned int get_le24(ByteIOContext *s)
467 {
468 unsigned int val;
469 val = get_le16(s);
470 val |= get_byte(s) << 16;
471 return val;
472 }
473
474 unsigned int get_le32(ByteIOContext *s)
475 {
476 unsigned int val;
477 val = get_le16(s);
478 val |= get_le16(s) << 16;
479 return val;
480 }
481
482 uint64_t get_le64(ByteIOContext *s)
483 {
484 uint64_t val;
485 val = (uint64_t)get_le32(s);
486 val |= (uint64_t)get_le32(s) << 32;
487 return val;
488 }
489
490 unsigned int get_be16(ByteIOContext *s)
491 {
492 unsigned int val;
493 val = get_byte(s) << 8;
494 val |= get_byte(s);
495 return val;
496 }
497
498 unsigned int get_be24(ByteIOContext *s)
499 {
500 unsigned int val;
501 val = get_be16(s) << 8;
502 val |= get_byte(s);
503 return val;
504 }
505 unsigned int get_be32(ByteIOContext *s)
506 {
507 unsigned int val;
508 val = get_be16(s) << 16;
509 val |= get_be16(s);
510 return val;
511 }
512
513 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
514 {
515 int i = 0;
516 char c;
517
518 while ((c = get_byte(s))) {
519 if (i < maxlen-1)
520 buf[i++] = c;
521 }
522
523 buf[i] = 0; /* Ensure null terminated, but may be truncated */
524
525 return buf;
526 }
527
528 uint64_t get_be64(ByteIOContext *s)
529 {
530 uint64_t val;
531 val = (uint64_t)get_be32(s) << 32;
532 val |= (uint64_t)get_be32(s);
533 return val;
534 }
535
536 uint64_t ff_get_v(ByteIOContext *bc){
537 uint64_t val = 0;
538 int tmp;
539
540 do{
541 tmp = get_byte(bc);
542 val= (val<<7) + (tmp&127);
543 }while(tmp&128);
544 return val;
545 }
546
547 int url_fdopen(ByteIOContext **s, URLContext *h)
548 {
549 uint8_t *buffer;
550 int buffer_size, max_packet_size;
551
552 max_packet_size = url_get_max_packet_size(h);
553 if (max_packet_size) {
554 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
555 } else {
556 buffer_size = IO_BUFFER_SIZE;
557 }
558 buffer = av_malloc(buffer_size);
559 if (!buffer)
560 return AVERROR(ENOMEM);
561
562 *s = av_mallocz(sizeof(ByteIOContext));
563 if(!*s) {
564 av_free(buffer);
565 return AVERROR(ENOMEM);
566 }
567
568 if (init_put_byte(*s, buffer, buffer_size,
569 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
570 url_read, url_write, url_seek) < 0) {
571 av_free(buffer);
572 av_freep(s);
573 return AVERROR(EIO);
574 }
575 (*s)->is_streamed = h->is_streamed;
576 (*s)->max_packet_size = max_packet_size;
577 if(h->prot) {
578 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
579 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
580 }
581 return 0;
582 }
583
584 int url_setbufsize(ByteIOContext *s, int buf_size)
585 {
586 uint8_t *buffer;
587 buffer = av_malloc(buf_size);
588 if (!buffer)
589 return AVERROR(ENOMEM);
590
591 av_free(s->buffer);
592 s->buffer = buffer;
593 s->buffer_size = buf_size;
594 s->buf_ptr = buffer;
595 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
596 return 0;
597 }
598
599 #if LIBAVFORMAT_VERSION_MAJOR < 53
600 int url_resetbuf(ByteIOContext *s, int flags)
601 #else
602 static int url_resetbuf(ByteIOContext *s, int flags)
603 #endif
604 {
605 #if LIBAVFORMAT_VERSION_MAJOR < 53
606 URLContext *h = s->opaque;
607 if ((flags & URL_RDWR) || (h && h->flags != flags && !h->flags & URL_RDWR))
608 return AVERROR(EINVAL);
609 #else
610 assert(flags == URL_WRONLY || flags == URL_RDONLY);
611 #endif
612
613 if (flags & URL_WRONLY) {
614 s->buf_end = s->buffer + s->buffer_size;
615 s->write_flag = 1;
616 } else {
617 s->buf_end = s->buffer;
618 s->write_flag = 0;
619 }
620 return 0;
621 }
622
623 int ff_rewind_with_probe_data(ByteIOContext *s, unsigned char *buf, int buf_size)
624 {
625 int64_t buffer_start;
626 int buffer_size;
627 int overlap, new_size;
628
629 if (s->write_flag)
630 return AVERROR(EINVAL);
631
632 buffer_size = s->buf_end - s->buffer;
633
634 /* the buffers must touch or overlap */
635 if ((buffer_start = s->pos - buffer_size) > buf_size)
636 return AVERROR(EINVAL);
637
638 overlap = buf_size - buffer_start;
639 new_size = buf_size + buffer_size - overlap;
640
641 if (new_size > buf_size) {
642 if (!(buf = av_realloc(buf, new_size)))
643 return AVERROR(ENOMEM);
644
645 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
646 buf_size = new_size;
647 }
648
649 av_free(s->buffer);
650 s->buf_ptr = s->buffer = buf;
651 s->pos = s->buffer_size = buf_size;
652 s->buf_end = s->buf_ptr + buf_size;
653 s->eof_reached = 0;
654 s->must_flush = 0;
655
656 return 0;
657 }
658
659 int url_fopen(ByteIOContext **s, const char *filename, int flags)
660 {
661 URLContext *h;
662 int err;
663
664 err = url_open(&h, filename, flags);
665 if (err < 0)
666 return err;
667 err = url_fdopen(s, h);
668 if (err < 0) {
669 url_close(h);
670 return err;
671 }
672 return 0;
673 }
674
675 int url_fclose(ByteIOContext *s)
676 {
677 URLContext *h = s->opaque;
678
679 av_free(s->buffer);
680 av_free(s);
681 return url_close(h);
682 }
683
684 URLContext *url_fileno(ByteIOContext *s)
685 {
686 return s->opaque;
687 }
688
689 #if CONFIG_MUXERS
690 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
691 {
692 va_list ap;
693 char buf[4096];
694 int ret;
695
696 va_start(ap, fmt);
697 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
698 va_end(ap);
699 put_buffer(s, buf, strlen(buf));
700 return ret;
701 }
702 #endif //CONFIG_MUXERS
703
704 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
705 {
706 int c;
707 char *q;
708
709 c = url_fgetc(s);
710 if (c == EOF)
711 return NULL;
712 q = buf;
713 for(;;) {
714 if (c == EOF || c == '\n')
715 break;
716 if ((q - buf) < buf_size - 1)
717 *q++ = c;
718 c = url_fgetc(s);
719 }
720 if (buf_size > 0)
721 *q = '\0';
722 return buf;
723 }
724
725 int url_fget_max_packet_size(ByteIOContext *s)
726 {
727 return s->max_packet_size;
728 }
729
730 int av_url_read_fpause(ByteIOContext *s, int pause)
731 {
732 if (!s->read_pause)
733 return AVERROR(ENOSYS);
734 return s->read_pause(s->opaque, pause);
735 }
736
737 int64_t av_url_read_fseek(ByteIOContext *s, int stream_index,
738 int64_t timestamp, int flags)
739 {
740 URLContext *h = s->opaque;
741 int64_t ret;
742 if (!s->read_seek)
743 return AVERROR(ENOSYS);
744 ret = s->read_seek(h, stream_index, timestamp, flags);
745 if(ret >= 0) {
746 int64_t pos;
747 s->buf_ptr = s->buf_end; // Flush buffer
748 pos = s->seek(h, 0, SEEK_CUR);
749 if (pos >= 0)
750 s->pos = pos;
751 else if (pos != AVERROR(ENOSYS))
752 ret = pos;
753 }
754 return ret;
755 }
756
757 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
758 * back to the server even if CONFIG_MUXERS is false. */
759 #if CONFIG_MUXERS || CONFIG_NETWORK
760 /* buffer handling */
761 int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
762 {
763 int ret;
764 *s = av_mallocz(sizeof(ByteIOContext));
765 if(!*s)
766 return AVERROR(ENOMEM);
767 ret = init_put_byte(*s, buf, buf_size,
768 (flags & URL_WRONLY || flags & URL_RDWR),
769 NULL, NULL, NULL, NULL);
770 if(ret != 0)
771 av_freep(s);
772 return ret;
773 }
774
775 int url_close_buf(ByteIOContext *s)
776 {
777 put_flush_packet(s);
778 return s->buf_ptr - s->buffer;
779 }
780
781 /* output in a dynamic buffer */
782
783 typedef struct DynBuffer {
784 int pos, size, allocated_size;
785 uint8_t *buffer;
786 int io_buffer_size;
787 uint8_t io_buffer[1];
788 } DynBuffer;
789
790 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
791 {
792 DynBuffer *d = opaque;
793 unsigned new_size, new_allocated_size;
794
795 /* reallocate buffer if needed */
796 new_size = d->pos + buf_size;
797 new_allocated_size = d->allocated_size;
798 if(new_size < d->pos || new_size > INT_MAX/2)
799 return -1;
800 while (new_size > new_allocated_size) {
801 if (!new_allocated_size)
802 new_allocated_size = new_size;
803 else
804 new_allocated_size += new_allocated_size / 2 + 1;
805 }
806
807 if (new_allocated_size > d->allocated_size) {
808 d->buffer = av_realloc(d->buffer, new_allocated_size);
809 if(d->buffer == NULL)
810 return AVERROR(ENOMEM);
811 d->allocated_size = new_allocated_size;
812 }
813 memcpy(d->buffer + d->pos, buf, buf_size);
814 d->pos = new_size;
815 if (d->pos > d->size)
816 d->size = d->pos;
817 return buf_size;
818 }
819
820 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
821 {
822 unsigned char buf1[4];
823 int ret;
824
825 /* packetized write: output the header */
826 AV_WB32(buf1, buf_size);
827 ret= dyn_buf_write(opaque, buf1, 4);
828 if(ret < 0)
829 return ret;
830
831 /* then the data */
832 return dyn_buf_write(opaque, buf, buf_size);
833 }
834
835 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
836 {
837 DynBuffer *d = opaque;
838
839 if (whence == SEEK_CUR)
840 offset += d->pos;
841 else if (whence == SEEK_END)
842 offset += d->size;
843 if (offset < 0 || offset > 0x7fffffffLL)
844 return -1;
845 d->pos = offset;
846 return 0;
847 }
848
849 static int url_open_dyn_buf_internal(ByteIOContext **s, int max_packet_size)
850 {
851 DynBuffer *d;
852 int ret;
853 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
854
855 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
856 return -1;
857 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
858 if (!d)
859 return AVERROR(ENOMEM);
860 *s = av_mallocz(sizeof(ByteIOContext));
861 if(!*s) {
862 av_free(d);
863 return AVERROR(ENOMEM);
864 }
865 d->io_buffer_size = io_buffer_size;
866 ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
867 1, d, NULL,
868 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
869 max_packet_size ? NULL : dyn_buf_seek);
870 if (ret == 0) {
871 (*s)->max_packet_size = max_packet_size;
872 } else {
873 av_free(d);
874 av_freep(s);
875 }
876 return ret;
877 }
878
879 int url_open_dyn_buf(ByteIOContext **s)
880 {
881 return url_open_dyn_buf_internal(s, 0);
882 }
883
884 int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
885 {
886 if (max_packet_size <= 0)
887 return -1;
888 return url_open_dyn_buf_internal(s, max_packet_size);
889 }
890
891 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
892 {
893 DynBuffer *d = s->opaque;
894 int size;
895
896 put_flush_packet(s);
897
898 *pbuffer = d->buffer;
899 size = d->size;
900 av_free(d);
901 av_free(s);
902 return size;
903 }
904 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */