29d07153578700be8504e50861a156411d2ebcf4
[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
134 if(!s)
135 return AVERROR(EINVAL);
136
137 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
138
139 if (whence != SEEK_CUR && whence != SEEK_SET)
140 return AVERROR(EINVAL);
141
142 if (whence == SEEK_CUR) {
143 offset1 = pos + (s->buf_ptr - s->buffer);
144 if (offset == 0)
145 return offset1;
146 offset += offset1;
147 }
148 offset1 = offset - pos;
149 if (!s->must_flush &&
150 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
151 /* can do the seek inside the buffer */
152 s->buf_ptr = s->buffer + offset1;
153 } else if(s->is_streamed && !s->write_flag && offset1 >= 0 &&
154 ( offset1 < (s->buf_end - s->buffer) + (1<<16)
155 || (whence & AVSEEK_FORCE))){
156 while(s->pos < offset && !s->eof_reached)
157 fill_buffer(s);
158 if (s->eof_reached)
159 return AVERROR(EPIPE);
160 s->buf_ptr = s->buf_end + offset - s->pos;
161 } else {
162 int64_t res = AVERROR(EPIPE);
163
164 #if CONFIG_MUXERS || CONFIG_NETWORK
165 if (s->write_flag) {
166 flush_buffer(s);
167 s->must_flush = 1;
168 }
169 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
170 if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
171 return res;
172 if (!s->write_flag)
173 s->buf_end = s->buffer;
174 s->buf_ptr = s->buffer;
175 s->pos = offset;
176 }
177 s->eof_reached = 0;
178 return offset;
179 }
180
181 void url_fskip(ByteIOContext *s, int64_t offset)
182 {
183 url_fseek(s, offset, SEEK_CUR);
184 }
185
186 int64_t url_ftell(ByteIOContext *s)
187 {
188 return url_fseek(s, 0, SEEK_CUR);
189 }
190
191 int64_t url_fsize(ByteIOContext *s)
192 {
193 int64_t size;
194
195 if(!s)
196 return AVERROR(EINVAL);
197
198 if (!s->seek)
199 return AVERROR(EPIPE);
200 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
201 if(size<0){
202 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
203 return size;
204 size++;
205 s->seek(s->opaque, s->pos, SEEK_SET);
206 }
207 return size;
208 }
209
210 int url_feof(ByteIOContext *s)
211 {
212 if(!s)
213 return 0;
214 return s->eof_reached;
215 }
216
217 int url_ferror(ByteIOContext *s)
218 {
219 if(!s)
220 return 0;
221 return s->error;
222 }
223
224 void put_le32(ByteIOContext *s, unsigned int val)
225 {
226 put_byte(s, val);
227 put_byte(s, val >> 8);
228 put_byte(s, val >> 16);
229 put_byte(s, val >> 24);
230 }
231
232 void put_be32(ByteIOContext *s, unsigned int val)
233 {
234 put_byte(s, val >> 24);
235 put_byte(s, val >> 16);
236 put_byte(s, val >> 8);
237 put_byte(s, val);
238 }
239
240 void put_strz(ByteIOContext *s, const char *str)
241 {
242 if (str)
243 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
244 else
245 put_byte(s, 0);
246 }
247
248 void put_le64(ByteIOContext *s, uint64_t val)
249 {
250 put_le32(s, (uint32_t)(val & 0xffffffff));
251 put_le32(s, (uint32_t)(val >> 32));
252 }
253
254 void put_be64(ByteIOContext *s, uint64_t val)
255 {
256 put_be32(s, (uint32_t)(val >> 32));
257 put_be32(s, (uint32_t)(val & 0xffffffff));
258 }
259
260 void put_le16(ByteIOContext *s, unsigned int val)
261 {
262 put_byte(s, val);
263 put_byte(s, val >> 8);
264 }
265
266 void put_be16(ByteIOContext *s, unsigned int val)
267 {
268 put_byte(s, val >> 8);
269 put_byte(s, val);
270 }
271
272 void put_le24(ByteIOContext *s, unsigned int val)
273 {
274 put_le16(s, val & 0xffff);
275 put_byte(s, val >> 16);
276 }
277
278 void put_be24(ByteIOContext *s, unsigned int val)
279 {
280 put_be16(s, val >> 8);
281 put_byte(s, val);
282 }
283
284 void put_tag(ByteIOContext *s, const char *tag)
285 {
286 while (*tag) {
287 put_byte(s, *tag++);
288 }
289 }
290
291 /* Input stream */
292
293 static void fill_buffer(ByteIOContext *s)
294 {
295 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
296 int len= s->buffer_size - (dst - s->buffer);
297
298 assert(s->buf_ptr == s->buf_end);
299
300 /* no need to do anything if EOF already reached */
301 if (s->eof_reached)
302 return;
303
304 if(s->update_checksum && dst == s->buffer){
305 if(s->buf_end > s->checksum_ptr)
306 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
307 s->checksum_ptr= s->buffer;
308 }
309
310 if(s->read_packet)
311 len = s->read_packet(s->opaque, dst, len);
312 else
313 len = 0;
314 if (len <= 0) {
315 /* do not modify buffer if EOF reached so that a seek back can
316 be done without rereading data */
317 s->eof_reached = 1;
318 if(len<0)
319 s->error= len;
320 } else {
321 s->pos += len;
322 s->buf_ptr = dst;
323 s->buf_end = dst + len;
324 }
325 }
326
327 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
328 unsigned int len)
329 {
330 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
331 }
332
333 unsigned long get_checksum(ByteIOContext *s)
334 {
335 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
336 s->update_checksum= NULL;
337 return s->checksum;
338 }
339
340 void init_checksum(ByteIOContext *s,
341 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
342 unsigned long checksum)
343 {
344 s->update_checksum= update_checksum;
345 if(s->update_checksum){
346 s->checksum= checksum;
347 s->checksum_ptr= s->buf_ptr;
348 }
349 }
350
351 /* XXX: put an inline version */
352 int get_byte(ByteIOContext *s)
353 {
354 if (s->buf_ptr < s->buf_end) {
355 return *s->buf_ptr++;
356 } else {
357 fill_buffer(s);
358 if (s->buf_ptr < s->buf_end)
359 return *s->buf_ptr++;
360 else
361 return 0;
362 }
363 }
364
365 int url_fgetc(ByteIOContext *s)
366 {
367 if (s->buf_ptr < s->buf_end) {
368 return *s->buf_ptr++;
369 } else {
370 fill_buffer(s);
371 if (s->buf_ptr < s->buf_end)
372 return *s->buf_ptr++;
373 else
374 return URL_EOF;
375 }
376 }
377
378 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
379 {
380 int len, size1;
381
382 size1 = size;
383 while (size > 0) {
384 len = s->buf_end - s->buf_ptr;
385 if (len > size)
386 len = size;
387 if (len == 0) {
388 if(size > s->buffer_size && !s->update_checksum){
389 if(s->read_packet)
390 len = s->read_packet(s->opaque, buf, size);
391 if (len <= 0) {
392 /* do not modify buffer if EOF reached so that a seek back can
393 be done without rereading data */
394 s->eof_reached = 1;
395 if(len<0)
396 s->error= len;
397 break;
398 } else {
399 s->pos += len;
400 size -= len;
401 buf += len;
402 s->buf_ptr = s->buffer;
403 s->buf_end = s->buffer/* + len*/;
404 }
405 }else{
406 fill_buffer(s);
407 len = s->buf_end - s->buf_ptr;
408 if (len == 0)
409 break;
410 }
411 } else {
412 memcpy(buf, s->buf_ptr, len);
413 buf += len;
414 s->buf_ptr += len;
415 size -= len;
416 }
417 }
418 if (size1 == size) {
419 if (url_ferror(s)) return url_ferror(s);
420 if (url_feof(s)) return AVERROR_EOF;
421 }
422 return size1 - size;
423 }
424
425 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
426 {
427 int len;
428
429 if(size<0)
430 return -1;
431
432 len = s->buf_end - s->buf_ptr;
433 if (len == 0) {
434 fill_buffer(s);
435 len = s->buf_end - s->buf_ptr;
436 }
437 if (len > size)
438 len = size;
439 memcpy(buf, s->buf_ptr, len);
440 s->buf_ptr += len;
441 if (!len) {
442 if (url_ferror(s)) return url_ferror(s);
443 if (url_feof(s)) return AVERROR_EOF;
444 }
445 return len;
446 }
447
448 unsigned int get_le16(ByteIOContext *s)
449 {
450 unsigned int val;
451 val = get_byte(s);
452 val |= get_byte(s) << 8;
453 return val;
454 }
455
456 unsigned int get_le24(ByteIOContext *s)
457 {
458 unsigned int val;
459 val = get_le16(s);
460 val |= get_byte(s) << 16;
461 return val;
462 }
463
464 unsigned int get_le32(ByteIOContext *s)
465 {
466 unsigned int val;
467 val = get_le16(s);
468 val |= get_le16(s) << 16;
469 return val;
470 }
471
472 uint64_t get_le64(ByteIOContext *s)
473 {
474 uint64_t val;
475 val = (uint64_t)get_le32(s);
476 val |= (uint64_t)get_le32(s) << 32;
477 return val;
478 }
479
480 unsigned int get_be16(ByteIOContext *s)
481 {
482 unsigned int val;
483 val = get_byte(s) << 8;
484 val |= get_byte(s);
485 return val;
486 }
487
488 unsigned int get_be24(ByteIOContext *s)
489 {
490 unsigned int val;
491 val = get_be16(s) << 8;
492 val |= get_byte(s);
493 return val;
494 }
495 unsigned int get_be32(ByteIOContext *s)
496 {
497 unsigned int val;
498 val = get_be16(s) << 16;
499 val |= get_be16(s);
500 return val;
501 }
502
503 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
504 {
505 int i = 0;
506 char c;
507
508 while ((c = get_byte(s))) {
509 if (i < maxlen-1)
510 buf[i++] = c;
511 }
512
513 buf[i] = 0; /* Ensure null terminated, but may be truncated */
514
515 return buf;
516 }
517
518 uint64_t get_be64(ByteIOContext *s)
519 {
520 uint64_t val;
521 val = (uint64_t)get_be32(s) << 32;
522 val |= (uint64_t)get_be32(s);
523 return val;
524 }
525
526 uint64_t ff_get_v(ByteIOContext *bc){
527 uint64_t val = 0;
528 int tmp;
529
530 do{
531 tmp = get_byte(bc);
532 val= (val<<7) + (tmp&127);
533 }while(tmp&128);
534 return val;
535 }
536
537 int url_fdopen(ByteIOContext **s, URLContext *h)
538 {
539 uint8_t *buffer;
540 int buffer_size, max_packet_size;
541
542 max_packet_size = url_get_max_packet_size(h);
543 if (max_packet_size) {
544 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
545 } else {
546 buffer_size = IO_BUFFER_SIZE;
547 }
548 buffer = av_malloc(buffer_size);
549 if (!buffer)
550 return AVERROR(ENOMEM);
551
552 *s = av_mallocz(sizeof(ByteIOContext));
553 if(!*s) {
554 av_free(buffer);
555 return AVERROR(ENOMEM);
556 }
557
558 if (init_put_byte(*s, buffer, buffer_size,
559 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
560 url_read, url_write, url_seek) < 0) {
561 av_free(buffer);
562 av_freep(s);
563 return AVERROR(EIO);
564 }
565 (*s)->is_streamed = h->is_streamed;
566 (*s)->max_packet_size = max_packet_size;
567 if(h->prot) {
568 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
569 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
570 }
571 return 0;
572 }
573
574 int url_setbufsize(ByteIOContext *s, int buf_size)
575 {
576 uint8_t *buffer;
577 buffer = av_malloc(buf_size);
578 if (!buffer)
579 return AVERROR(ENOMEM);
580
581 av_free(s->buffer);
582 s->buffer = buffer;
583 s->buffer_size = buf_size;
584 s->buf_ptr = buffer;
585 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
586 return 0;
587 }
588
589 #if LIBAVFORMAT_VERSION_MAJOR < 53
590 int url_resetbuf(ByteIOContext *s, int flags)
591 #else
592 static int url_resetbuf(ByteIOContext *s, int flags)
593 #endif
594 {
595 #if LIBAVFORMAT_VERSION_MAJOR < 53
596 URLContext *h = s->opaque;
597 if ((flags & URL_RDWR) || (h && h->flags != flags && !h->flags & URL_RDWR))
598 return AVERROR(EINVAL);
599 #else
600 assert(flags == URL_WRONLY || flags == URL_RDONLY);
601 #endif
602
603 if (flags & URL_WRONLY) {
604 s->buf_end = s->buffer + s->buffer_size;
605 s->write_flag = 1;
606 } else {
607 s->buf_end = s->buffer;
608 s->write_flag = 0;
609 }
610 return 0;
611 }
612
613 int url_fopen(ByteIOContext **s, const char *filename, int flags)
614 {
615 URLContext *h;
616 int err;
617
618 err = url_open(&h, filename, flags);
619 if (err < 0)
620 return err;
621 err = url_fdopen(s, h);
622 if (err < 0) {
623 url_close(h);
624 return err;
625 }
626 return 0;
627 }
628
629 int url_fclose(ByteIOContext *s)
630 {
631 URLContext *h = s->opaque;
632
633 av_free(s->buffer);
634 av_free(s);
635 return url_close(h);
636 }
637
638 URLContext *url_fileno(ByteIOContext *s)
639 {
640 return s->opaque;
641 }
642
643 #if CONFIG_MUXERS
644 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
645 {
646 va_list ap;
647 char buf[4096];
648 int ret;
649
650 va_start(ap, fmt);
651 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
652 va_end(ap);
653 put_buffer(s, buf, strlen(buf));
654 return ret;
655 }
656 #endif //CONFIG_MUXERS
657
658 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
659 {
660 int c;
661 char *q;
662
663 c = url_fgetc(s);
664 if (c == EOF)
665 return NULL;
666 q = buf;
667 for(;;) {
668 if (c == EOF || c == '\n')
669 break;
670 if ((q - buf) < buf_size - 1)
671 *q++ = c;
672 c = url_fgetc(s);
673 }
674 if (buf_size > 0)
675 *q = '\0';
676 return buf;
677 }
678
679 int url_fget_max_packet_size(ByteIOContext *s)
680 {
681 return s->max_packet_size;
682 }
683
684 int av_url_read_fpause(ByteIOContext *s, int pause)
685 {
686 if (!s->read_pause)
687 return AVERROR(ENOSYS);
688 return s->read_pause(s->opaque, pause);
689 }
690
691 int64_t av_url_read_fseek(ByteIOContext *s, int stream_index,
692 int64_t timestamp, int flags)
693 {
694 URLContext *h = s->opaque;
695 int64_t ret;
696 if (!s->read_seek)
697 return AVERROR(ENOSYS);
698 ret = s->read_seek(h, stream_index, timestamp, flags);
699 if(ret >= 0) {
700 s->buf_ptr = s->buf_end; // Flush buffer
701 s->pos = s->seek(h, 0, SEEK_CUR);
702 }
703 return ret;
704 }
705
706 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
707 * back to the server even if CONFIG_MUXERS is false. */
708 #if CONFIG_MUXERS || CONFIG_NETWORK
709 /* buffer handling */
710 int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
711 {
712 int ret;
713 *s = av_mallocz(sizeof(ByteIOContext));
714 if(!*s)
715 return AVERROR(ENOMEM);
716 ret = init_put_byte(*s, buf, buf_size,
717 (flags & URL_WRONLY || flags & URL_RDWR),
718 NULL, NULL, NULL, NULL);
719 if(ret != 0)
720 av_freep(s);
721 return ret;
722 }
723
724 int url_close_buf(ByteIOContext *s)
725 {
726 put_flush_packet(s);
727 return s->buf_ptr - s->buffer;
728 }
729
730 /* output in a dynamic buffer */
731
732 typedef struct DynBuffer {
733 int pos, size, allocated_size;
734 uint8_t *buffer;
735 int io_buffer_size;
736 uint8_t io_buffer[1];
737 } DynBuffer;
738
739 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
740 {
741 DynBuffer *d = opaque;
742 unsigned new_size, new_allocated_size;
743
744 /* reallocate buffer if needed */
745 new_size = d->pos + buf_size;
746 new_allocated_size = d->allocated_size;
747 if(new_size < d->pos || new_size > INT_MAX/2)
748 return -1;
749 while (new_size > new_allocated_size) {
750 if (!new_allocated_size)
751 new_allocated_size = new_size;
752 else
753 new_allocated_size += new_allocated_size / 2 + 1;
754 }
755
756 if (new_allocated_size > d->allocated_size) {
757 d->buffer = av_realloc(d->buffer, new_allocated_size);
758 if(d->buffer == NULL)
759 return AVERROR(ENOMEM);
760 d->allocated_size = new_allocated_size;
761 }
762 memcpy(d->buffer + d->pos, buf, buf_size);
763 d->pos = new_size;
764 if (d->pos > d->size)
765 d->size = d->pos;
766 return buf_size;
767 }
768
769 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
770 {
771 unsigned char buf1[4];
772 int ret;
773
774 /* packetized write: output the header */
775 AV_WB32(buf1, buf_size);
776 ret= dyn_buf_write(opaque, buf1, 4);
777 if(ret < 0)
778 return ret;
779
780 /* then the data */
781 return dyn_buf_write(opaque, buf, buf_size);
782 }
783
784 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
785 {
786 DynBuffer *d = opaque;
787
788 if (whence == SEEK_CUR)
789 offset += d->pos;
790 else if (whence == SEEK_END)
791 offset += d->size;
792 if (offset < 0 || offset > 0x7fffffffLL)
793 return -1;
794 d->pos = offset;
795 return 0;
796 }
797
798 static int url_open_dyn_buf_internal(ByteIOContext **s, int max_packet_size)
799 {
800 DynBuffer *d;
801 int ret;
802 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
803
804 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
805 return -1;
806 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
807 if (!d)
808 return AVERROR(ENOMEM);
809 *s = av_mallocz(sizeof(ByteIOContext));
810 if(!*s) {
811 av_free(d);
812 return AVERROR(ENOMEM);
813 }
814 d->io_buffer_size = io_buffer_size;
815 ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
816 1, d, NULL,
817 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
818 max_packet_size ? NULL : dyn_buf_seek);
819 if (ret == 0) {
820 (*s)->max_packet_size = max_packet_size;
821 } else {
822 av_free(d);
823 av_freep(s);
824 }
825 return ret;
826 }
827
828 int url_open_dyn_buf(ByteIOContext **s)
829 {
830 return url_open_dyn_buf_internal(s, 0);
831 }
832
833 int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
834 {
835 if (max_packet_size <= 0)
836 return -1;
837 return url_open_dyn_buf_internal(s, max_packet_size);
838 }
839
840 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
841 {
842 DynBuffer *d = s->opaque;
843 int size;
844
845 put_flush_packet(s);
846
847 *pbuffer = d->buffer;
848 size = d->size;
849 av_free(d);
850 av_free(s);
851 return size;
852 }
853 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */