2 * Buffered I/O for ffmpeg system
3 * Copyright (c) 2000,2001 Fabrice Bellard
5 * This file is part of Libav.
7 * Libav 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.
12 * Libav 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.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/crc.h"
23 #include "libavutil/intreadwrite.h"
26 #include "avio_internal.h"
30 #define IO_BUFFER_SIZE 32768
33 * Do seeks within this distance ahead of the current buffer by skipping
34 * data instead of calling the protocol seek function, for seekable
37 #define SHORT_SEEK_THRESHOLD 4096
39 static void fill_buffer(AVIOContext *s);
40 #if !FF_API_URL_RESETBUF
41 static int url_resetbuf(AVIOContext *s, int flags);
44 int ffio_init_context(AVIOContext *s,
45 unsigned char *buffer,
49 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
50 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
51 int64_t (*seek)(void *opaque, int64_t offset, int whence))
54 s->buffer_size = buffer_size;
57 url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
58 s->write_packet = write_packet;
59 s->read_packet = read_packet;
68 s->seekable = AVIO_SEEKABLE_NORMAL;
69 s->max_packet_size = 0;
70 s->update_checksum= NULL;
71 if(!read_packet && !write_flag){
73 s->buf_end = s->buffer + buffer_size;
81 int init_put_byte(AVIOContext *s,
82 unsigned char *buffer,
86 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
87 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
88 int64_t (*seek)(void *opaque, int64_t offset, int whence))
90 return ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
91 read_packet, write_packet, seek);
93 AVIOContext *av_alloc_put_byte(
94 unsigned char *buffer,
98 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
99 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
100 int64_t (*seek)(void *opaque, int64_t offset, int whence))
102 return avio_alloc_context(buffer, buffer_size, write_flag, opaque,
103 read_packet, write_packet, seek);
107 AVIOContext *avio_alloc_context(
108 unsigned char *buffer,
112 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
113 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
114 int64_t (*seek)(void *opaque, int64_t offset, int whence))
116 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
117 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
118 read_packet, write_packet, seek);
122 static void flush_buffer(AVIOContext *s)
124 if (s->buf_ptr > s->buffer) {
125 if (s->write_packet && !s->error){
126 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
131 if(s->update_checksum){
132 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
133 s->checksum_ptr= s->buffer;
135 s->pos += s->buf_ptr - s->buffer;
137 s->buf_ptr = s->buffer;
140 void avio_w8(AVIOContext *s, int b)
143 if (s->buf_ptr >= s->buf_end)
147 void ffio_fill(AVIOContext *s, int b, int count)
150 int len = FFMIN(s->buf_end - s->buf_ptr, count);
151 memset(s->buf_ptr, b, len);
154 if (s->buf_ptr >= s->buf_end)
161 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
164 int len = FFMIN(s->buf_end - s->buf_ptr, size);
165 memcpy(s->buf_ptr, buf, len);
168 if (s->buf_ptr >= s->buf_end)
176 void avio_flush(AVIOContext *s)
182 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
186 int force = whence & AVSEEK_FORCE;
187 whence &= ~AVSEEK_FORCE;
190 return AVERROR(EINVAL);
192 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
194 if (whence != SEEK_CUR && whence != SEEK_SET)
195 return AVERROR(EINVAL);
197 if (whence == SEEK_CUR) {
198 offset1 = pos + (s->buf_ptr - s->buffer);
203 offset1 = offset - pos;
204 if (!s->must_flush &&
205 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
206 /* can do the seek inside the buffer */
207 s->buf_ptr = s->buffer + offset1;
208 } else if ((!s->seekable ||
209 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
210 !s->write_flag && offset1 >= 0 &&
211 (whence != SEEK_END || force)) {
212 while(s->pos < offset && !s->eof_reached)
216 s->buf_ptr = s->buf_end + offset - s->pos;
220 #if CONFIG_MUXERS || CONFIG_NETWORK
225 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
227 return AVERROR(EPIPE);
228 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
231 s->buf_end = s->buffer;
232 s->buf_ptr = s->buffer;
240 int url_fskip(AVIOContext *s, int64_t offset)
242 int64_t ret = avio_seek(s, offset, SEEK_CUR);
243 return ret < 0 ? ret : 0;
246 int64_t url_ftell(AVIOContext *s)
248 return avio_seek(s, 0, SEEK_CUR);
252 int64_t avio_size(AVIOContext *s)
257 return AVERROR(EINVAL);
260 return AVERROR(ENOSYS);
261 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
263 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
266 s->seek(s->opaque, s->pos, SEEK_SET);
272 int url_feof(AVIOContext *s)
276 return s->eof_reached;
279 int url_ferror(AVIOContext *s)
287 void avio_wl32(AVIOContext *s, unsigned int val)
290 avio_w8(s, val >> 8);
291 avio_w8(s, val >> 16);
292 avio_w8(s, val >> 24);
295 void avio_wb32(AVIOContext *s, unsigned int val)
297 avio_w8(s, val >> 24);
298 avio_w8(s, val >> 16);
299 avio_w8(s, val >> 8);
304 void put_strz(AVIOContext *s, const char *str)
306 avio_put_str(s, str);
309 #define GET(name, type) \
310 type get_be ##name(AVIOContext *s) \
312 return avio_rb ##name(s);\
314 type get_le ##name(AVIOContext *s) \
316 return avio_rl ##name(s);\
319 GET(16, unsigned int)
320 GET(24, unsigned int)
321 GET(32, unsigned int)
326 #define PUT(name, type ) \
327 void put_le ##name(AVIOContext *s, type val)\
329 avio_wl ##name(s, val);\
331 void put_be ##name(AVIOContext *s, type val)\
333 avio_wb ##name(s, val);\
336 PUT(16, unsigned int)
337 PUT(24, unsigned int)
338 PUT(32, unsigned int)
342 int get_byte(AVIOContext *s)
346 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
348 return avio_read(s, buf, size);
350 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
352 return ffio_read_partial(s, buf, size);
354 void put_byte(AVIOContext *s, int val)
358 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
360 avio_write(s, buf, size);
362 void put_nbyte(AVIOContext *s, int b, int count)
364 ffio_fill(s, b, count);
367 int url_fopen(AVIOContext **s, const char *filename, int flags)
369 return avio_open(s, filename, flags);
371 int url_fclose(AVIOContext *s)
373 return avio_close(s);
375 int64_t url_fseek(AVIOContext *s, int64_t offset, int whence)
377 return avio_seek(s, offset, whence);
379 int64_t url_fsize(AVIOContext *s)
383 int url_setbufsize(AVIOContext *s, int buf_size)
385 return ffio_set_buf_size(s, buf_size);
387 int url_fprintf(AVIOContext *s, const char *fmt, ...)
394 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
396 avio_write(s, buf, strlen(buf));
399 void put_flush_packet(AVIOContext *s)
403 int av_url_read_fpause(AVIOContext *s, int pause)
405 return ffio_read_pause(s, pause);
407 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
408 int64_t timestamp, int flags)
410 return ffio_read_seek(s, stream_index, timestamp, flags);
412 void init_checksum(AVIOContext *s,
413 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
414 unsigned long checksum)
416 ffio_init_checksum(s, update_checksum, checksum);
418 unsigned long get_checksum(AVIOContext *s)
420 return ffio_get_checksum(s);
422 int url_open_dyn_buf(AVIOContext **s)
424 return avio_open_dyn_buf(s);
426 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
428 return avio_close_dyn_buf(s, pbuffer);
432 int avio_put_str(AVIOContext *s, const char *str)
437 avio_write(s, (const unsigned char *) str, len);
443 int avio_put_str16le(AVIOContext *s, const char *str)
445 const uint8_t *q = str;
452 GET_UTF8(ch, *q++, break;)
453 PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
460 int ff_get_v_length(uint64_t val){
469 void ff_put_v(AVIOContext *bc, uint64_t val){
470 int i= ff_get_v_length(val);
473 avio_w8(bc, 128 | (val>>(7*i)));
475 avio_w8(bc, val&127);
478 void avio_wl64(AVIOContext *s, uint64_t val)
480 avio_wl32(s, (uint32_t)(val & 0xffffffff));
481 avio_wl32(s, (uint32_t)(val >> 32));
484 void avio_wb64(AVIOContext *s, uint64_t val)
486 avio_wb32(s, (uint32_t)(val >> 32));
487 avio_wb32(s, (uint32_t)(val & 0xffffffff));
490 void avio_wl16(AVIOContext *s, unsigned int val)
493 avio_w8(s, val >> 8);
496 void avio_wb16(AVIOContext *s, unsigned int val)
498 avio_w8(s, val >> 8);
502 void avio_wl24(AVIOContext *s, unsigned int val)
504 avio_wl16(s, val & 0xffff);
505 avio_w8(s, val >> 16);
508 void avio_wb24(AVIOContext *s, unsigned int val)
510 avio_wb16(s, val >> 8);
515 void put_tag(AVIOContext *s, const char *tag)
525 static void fill_buffer(AVIOContext *s)
527 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_end : s->buffer;
528 int len= s->buffer_size - (dst - s->buffer);
529 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
531 /* no need to do anything if EOF already reached */
535 if(s->update_checksum && dst == s->buffer){
536 if(s->buf_end > s->checksum_ptr)
537 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
538 s->checksum_ptr= s->buffer;
541 /* make buffer smaller in case it ended up large after probing */
542 if (s->buffer_size > max_buffer_size) {
543 ffio_set_buf_size(s, max_buffer_size);
545 s->checksum_ptr = dst = s->buffer;
546 len = s->buffer_size;
550 len = s->read_packet(s->opaque, dst, len);
554 /* do not modify buffer if EOF reached so that a seek back can
555 be done without rereading data */
562 s->buf_end = dst + len;
566 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
569 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
572 unsigned long ffio_get_checksum(AVIOContext *s)
574 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
575 s->update_checksum= NULL;
579 void ffio_init_checksum(AVIOContext *s,
580 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
581 unsigned long checksum)
583 s->update_checksum= update_checksum;
584 if(s->update_checksum){
585 s->checksum= checksum;
586 s->checksum_ptr= s->buf_ptr;
590 /* XXX: put an inline version */
591 int avio_r8(AVIOContext *s)
593 if (s->buf_ptr >= s->buf_end)
595 if (s->buf_ptr < s->buf_end)
596 return *s->buf_ptr++;
601 int url_fgetc(AVIOContext *s)
603 if (s->buf_ptr >= s->buf_end)
605 if (s->buf_ptr < s->buf_end)
606 return *s->buf_ptr++;
611 int avio_read(AVIOContext *s, unsigned char *buf, int size)
617 len = s->buf_end - s->buf_ptr;
621 if(size > s->buffer_size && !s->update_checksum){
623 len = s->read_packet(s->opaque, buf, size);
625 /* do not modify buffer if EOF reached so that a seek back can
626 be done without rereading data */
635 s->buf_ptr = s->buffer;
636 s->buf_end = s->buffer/* + len*/;
640 len = s->buf_end - s->buf_ptr;
645 memcpy(buf, s->buf_ptr, len);
652 if (s->error) return s->error;
653 if (s->eof_reached) return AVERROR_EOF;
658 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
665 len = s->buf_end - s->buf_ptr;
668 len = s->buf_end - s->buf_ptr;
672 memcpy(buf, s->buf_ptr, len);
675 if (s->error) return s->error;
676 if (s->eof_reached) return AVERROR_EOF;
681 unsigned int avio_rl16(AVIOContext *s)
685 val |= avio_r8(s) << 8;
689 unsigned int avio_rl24(AVIOContext *s)
693 val |= avio_r8(s) << 16;
697 unsigned int avio_rl32(AVIOContext *s)
701 val |= avio_rl16(s) << 16;
705 uint64_t avio_rl64(AVIOContext *s)
708 val = (uint64_t)avio_rl32(s);
709 val |= (uint64_t)avio_rl32(s) << 32;
713 unsigned int avio_rb16(AVIOContext *s)
716 val = avio_r8(s) << 8;
721 unsigned int avio_rb24(AVIOContext *s)
724 val = avio_rb16(s) << 8;
728 unsigned int avio_rb32(AVIOContext *s)
731 val = avio_rb16(s) << 16;
737 char *get_strz(AVIOContext *s, char *buf, int maxlen)
739 avio_get_str(s, INT_MAX, buf, maxlen);
744 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
751 if (c && i < maxlen-1)
753 } while (c != '\n' && c);
759 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
763 // reserve 1 byte for terminating 0
764 buflen = FFMIN(buflen - 1, maxlen);
765 for (i = 0; i < buflen; i++)
766 if (!(buf[i] = avio_r8(s)))
770 for (; i < maxlen; i++)
776 #define GET_STR16(type, read) \
777 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
781 while (ret + 1 < maxlen) {\
784 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
787 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
793 GET_STR16(le, avio_rl16)
794 GET_STR16(be, avio_rb16)
798 uint64_t avio_rb64(AVIOContext *s)
801 val = (uint64_t)avio_rb32(s) << 32;
802 val |= (uint64_t)avio_rb32(s);
806 uint64_t ffio_read_varlen(AVIOContext *bc){
812 val= (val<<7) + (tmp&127);
817 int url_fdopen(AVIOContext **s, URLContext *h)
820 int buffer_size, max_packet_size;
822 max_packet_size = url_get_max_packet_size(h);
823 if (max_packet_size) {
824 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
826 buffer_size = IO_BUFFER_SIZE;
828 buffer = av_malloc(buffer_size);
830 return AVERROR(ENOMEM);
832 *s = av_mallocz(sizeof(AVIOContext));
835 return AVERROR(ENOMEM);
838 if (ffio_init_context(*s, buffer, buffer_size,
839 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
840 url_read, url_write, url_seek) < 0) {
846 (*s)->is_streamed = h->is_streamed;
848 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
849 (*s)->max_packet_size = max_packet_size;
851 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
852 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
857 int ffio_set_buf_size(AVIOContext *s, int buf_size)
860 buffer = av_malloc(buf_size);
862 return AVERROR(ENOMEM);
866 s->buffer_size = buf_size;
868 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
872 #if FF_API_URL_RESETBUF
873 int url_resetbuf(AVIOContext *s, int flags)
875 static int url_resetbuf(AVIOContext *s, int flags)
878 #if FF_API_URL_RESETBUF
879 if (flags & URL_RDWR)
880 return AVERROR(EINVAL);
882 assert(flags == URL_WRONLY || flags == URL_RDONLY);
885 if (flags & URL_WRONLY) {
886 s->buf_end = s->buffer + s->buffer_size;
889 s->buf_end = s->buffer;
895 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
897 int64_t buffer_start;
899 int overlap, new_size, alloc_size;
902 return AVERROR(EINVAL);
904 buffer_size = s->buf_end - s->buffer;
906 /* the buffers must touch or overlap */
907 if ((buffer_start = s->pos - buffer_size) > buf_size)
908 return AVERROR(EINVAL);
910 overlap = buf_size - buffer_start;
911 new_size = buf_size + buffer_size - overlap;
913 alloc_size = FFMAX(s->buffer_size, new_size);
914 if (alloc_size > buf_size)
915 if (!(buf = av_realloc(buf, alloc_size)))
916 return AVERROR(ENOMEM);
918 if (new_size > buf_size) {
919 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
924 s->buf_ptr = s->buffer = buf;
925 s->buffer_size = alloc_size;
927 s->buf_end = s->buf_ptr + buf_size;
934 int avio_open(AVIOContext **s, const char *filename, int flags)
939 err = url_open(&h, filename, flags);
942 err = url_fdopen(s, h);
950 int avio_close(AVIOContext *s)
952 URLContext *h = s->opaque;
960 URLContext *url_fileno(AVIOContext *s)
966 int avio_printf(AVIOContext *s, const char *fmt, ...)
973 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
975 avio_write(s, buf, strlen(buf));
980 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
990 if (s->eof_reached || c == '\n')
992 if ((q - buf) < buf_size - 1)
1001 int url_fget_max_packet_size(AVIOContext *s)
1003 return s->max_packet_size;
1007 int ffio_read_pause(AVIOContext *s, int pause)
1010 return AVERROR(ENOSYS);
1011 return s->read_pause(s->opaque, pause);
1014 int64_t ffio_read_seek(AVIOContext *s, int stream_index,
1015 int64_t timestamp, int flags)
1017 URLContext *h = s->opaque;
1020 return AVERROR(ENOSYS);
1021 ret = s->read_seek(h, stream_index, timestamp, flags);
1024 s->buf_ptr = s->buf_end; // Flush buffer
1025 pos = s->seek(h, 0, SEEK_CUR);
1028 else if (pos != AVERROR(ENOSYS))
1034 /* avio_open_dyn_buf and avio_close_dyn_buf are used in rtp.c to send a response
1035 * back to the server even if CONFIG_MUXERS is false. */
1036 #if CONFIG_MUXERS || CONFIG_NETWORK
1037 /* buffer handling */
1039 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
1042 *s = av_mallocz(sizeof(AVIOContext));
1044 return AVERROR(ENOMEM);
1045 ret = ffio_init_context(*s, buf, buf_size,
1046 (flags & URL_WRONLY || flags & URL_RDWR),
1047 NULL, NULL, NULL, NULL);
1053 int url_close_buf(AVIOContext *s)
1056 return s->buf_ptr - s->buffer;
1060 /* output in a dynamic buffer */
1062 typedef struct DynBuffer {
1063 int pos, size, allocated_size;
1066 uint8_t io_buffer[1];
1069 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1071 DynBuffer *d = opaque;
1072 unsigned new_size, new_allocated_size;
1074 /* reallocate buffer if needed */
1075 new_size = d->pos + buf_size;
1076 new_allocated_size = d->allocated_size;
1077 if(new_size < d->pos || new_size > INT_MAX/2)
1079 while (new_size > new_allocated_size) {
1080 if (!new_allocated_size)
1081 new_allocated_size = new_size;
1083 new_allocated_size += new_allocated_size / 2 + 1;
1086 if (new_allocated_size > d->allocated_size) {
1087 d->buffer = av_realloc(d->buffer, new_allocated_size);
1088 if(d->buffer == NULL)
1089 return AVERROR(ENOMEM);
1090 d->allocated_size = new_allocated_size;
1092 memcpy(d->buffer + d->pos, buf, buf_size);
1094 if (d->pos > d->size)
1099 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1101 unsigned char buf1[4];
1104 /* packetized write: output the header */
1105 AV_WB32(buf1, buf_size);
1106 ret= dyn_buf_write(opaque, buf1, 4);
1111 return dyn_buf_write(opaque, buf, buf_size);
1114 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1116 DynBuffer *d = opaque;
1118 if (whence == SEEK_CUR)
1120 else if (whence == SEEK_END)
1122 if (offset < 0 || offset > 0x7fffffffLL)
1128 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1132 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1134 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1136 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1138 return AVERROR(ENOMEM);
1139 *s = av_mallocz(sizeof(AVIOContext));
1142 return AVERROR(ENOMEM);
1144 d->io_buffer_size = io_buffer_size;
1145 ret = ffio_init_context(*s, d->io_buffer, io_buffer_size,
1147 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1148 max_packet_size ? NULL : dyn_buf_seek);
1150 (*s)->max_packet_size = max_packet_size;
1158 int avio_open_dyn_buf(AVIOContext **s)
1160 return url_open_dyn_buf_internal(s, 0);
1163 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1165 if (max_packet_size <= 0)
1167 return url_open_dyn_buf_internal(s, max_packet_size);
1170 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1172 DynBuffer *d = s->opaque;
1174 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1177 /* don't attempt to pad fixed-size packet buffers */
1178 if (!s->max_packet_size) {
1179 avio_write(s, padbuf, sizeof(padbuf));
1180 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1185 *pbuffer = d->buffer;
1189 return size - padding;
1191 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */