3 * Copyright (c) 2000,2001 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/bprint.h"
23 #include "libavutil/crc.h"
24 #include "libavutil/dict.h"
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/log.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/avassert.h"
31 #include "avio_internal.h"
36 #define IO_BUFFER_SIZE 32768
39 * Do seeks within this distance ahead of the current buffer by skipping
40 * data instead of calling the protocol seek function, for seekable
43 #define SHORT_SEEK_THRESHOLD 4096
45 static void *ff_avio_child_next(void *obj, void *prev)
48 return prev ? NULL : s->opaque;
51 static const AVClass *ff_avio_child_class_next(const AVClass *prev)
53 return prev ? NULL : &ffurl_context_class;
56 static const AVOption ff_avio_options[] = {
60 const AVClass ff_avio_class = {
61 .class_name = "AVIOContext",
62 .item_name = av_default_item_name,
63 .version = LIBAVUTIL_VERSION_INT,
64 .option = ff_avio_options,
65 .child_next = ff_avio_child_next,
66 .child_class_next = ff_avio_child_class_next,
69 static void fill_buffer(AVIOContext *s);
70 static int url_resetbuf(AVIOContext *s, int flags);
72 int ffio_init_context(AVIOContext *s,
73 unsigned char *buffer,
77 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
78 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
79 int64_t (*seek)(void *opaque, int64_t offset, int whence))
83 s->buffer_size = buffer_size;
88 url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
90 s->write_packet = write_packet;
91 s->read_packet = read_packet;
97 s->seekable = seek ? AVIO_SEEKABLE_NORMAL : 0;
98 s->max_packet_size = 0;
99 s->update_checksum = NULL;
101 if (!read_packet && !write_flag) {
102 s->pos = buffer_size;
103 s->buf_end = s->buffer + buffer_size;
105 s->read_pause = NULL;
111 AVIOContext *avio_alloc_context(
112 unsigned char *buffer,
116 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
117 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
118 int64_t (*seek)(void *opaque, int64_t offset, int whence))
120 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
123 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
124 read_packet, write_packet, seek);
128 static void writeout(AVIOContext *s, const uint8_t *data, int len)
130 if (s->write_packet && !s->error) {
131 int ret = s->write_packet(s->opaque, (uint8_t *)data, len);
136 s->writeout_count ++;
140 static void flush_buffer(AVIOContext *s)
142 if (s->write_flag && s->buf_ptr > s->buffer) {
143 writeout(s, s->buffer, s->buf_ptr - s->buffer);
144 if (s->update_checksum) {
145 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
146 s->buf_ptr - s->checksum_ptr);
147 s->checksum_ptr = s->buffer;
150 s->buf_ptr = s->buffer;
152 s->buf_end = s->buffer;
155 void avio_w8(AVIOContext *s, int b)
157 av_assert2(b>=-128 && b<=255);
159 if (s->buf_ptr >= s->buf_end)
163 void ffio_fill(AVIOContext *s, int b, int count)
166 int len = FFMIN(s->buf_end - s->buf_ptr, count);
167 memset(s->buf_ptr, b, len);
170 if (s->buf_ptr >= s->buf_end)
177 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
179 if (s->direct && !s->update_checksum) {
181 writeout(s, buf, size);
185 int len = FFMIN(s->buf_end - s->buf_ptr, size);
186 memcpy(s->buf_ptr, buf, len);
189 if (s->buf_ptr >= s->buf_end)
197 void avio_flush(AVIOContext *s)
203 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
207 int force = whence & AVSEEK_FORCE;
209 whence &= ~AVSEEK_FORCE;
212 return AVERROR(EINVAL);
214 buffer_size = s->buf_end - s->buffer;
215 pos = s->pos - (s->write_flag ? 0 : buffer_size);
217 if (whence != SEEK_CUR && whence != SEEK_SET)
218 return AVERROR(EINVAL);
220 if (whence == SEEK_CUR) {
221 offset1 = pos + (s->buf_ptr - s->buffer);
227 return AVERROR(EINVAL);
229 offset1 = offset - pos;
230 if (!s->must_flush && (!s->direct || !s->seek) &&
231 offset1 >= 0 && offset1 <= buffer_size - s->write_flag) {
232 /* can do the seek inside the buffer */
233 s->buf_ptr = s->buffer + offset1;
234 } else if ((!s->seekable ||
235 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
236 !s->write_flag && offset1 >= 0 &&
237 (!s->direct || !s->seek) &&
238 (whence != SEEK_END || force)) {
239 while(s->pos < offset && !s->eof_reached)
243 s->buf_ptr = s->buf_end + offset - s->pos;
244 } else if(!s->write_flag && offset1 < 0 && -offset1 < buffer_size>>1 && s->seek && offset > 0) {
247 pos -= FFMIN(buffer_size>>1, pos);
248 if ((res = s->seek(s->opaque, pos, SEEK_SET)) < 0)
251 s->buf_ptr = s->buffer;
255 return avio_seek(s, offset, SEEK_SET | force);
263 return AVERROR(EPIPE);
264 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
268 s->buf_end = s->buffer;
269 s->buf_ptr = s->buffer;
276 int64_t avio_skip(AVIOContext *s, int64_t offset)
278 return avio_seek(s, offset, SEEK_CUR);
281 int64_t avio_size(AVIOContext *s)
286 return AVERROR(EINVAL);
289 return AVERROR(ENOSYS);
290 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
292 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
295 s->seek(s->opaque, s->pos, SEEK_SET);
300 int avio_feof(AVIOContext *s)
308 return s->eof_reached;
312 int url_feof(AVIOContext *s)
318 void avio_wl32(AVIOContext *s, unsigned int val)
320 avio_w8(s, (uint8_t) val );
321 avio_w8(s, (uint8_t)(val >> 8 ));
322 avio_w8(s, (uint8_t)(val >> 16));
323 avio_w8(s, val >> 24 );
326 void avio_wb32(AVIOContext *s, unsigned int val)
328 avio_w8(s, val >> 24 );
329 avio_w8(s, (uint8_t)(val >> 16));
330 avio_w8(s, (uint8_t)(val >> 8 ));
331 avio_w8(s, (uint8_t) val );
334 int avio_put_str(AVIOContext *s, const char *str)
339 avio_write(s, (const unsigned char *) str, len);
345 static inline int put_str16(AVIOContext *s, const char *str, const int be)
347 const uint8_t *q = str;
355 GET_UTF8(ch, *q++, goto invalid;)
356 PUT_UTF16(ch, tmp, be ? avio_wb16(s, tmp) : avio_wl16(s, tmp);
360 av_log(s, AV_LOG_ERROR, "Invaid UTF8 sequence in avio_put_str16%s\n", be ? "be" : "le");
361 err = AVERROR(EINVAL);
373 #define PUT_STR16(type, big_endian) \
374 int avio_put_str16 ## type(AVIOContext *s, const char *str) \
376 return put_str16(s, str, big_endian); \
384 int ff_get_v_length(uint64_t val)
394 void ff_put_v(AVIOContext *bc, uint64_t val)
396 int i = ff_get_v_length(val);
399 avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
401 avio_w8(bc, val & 127);
404 void avio_wl64(AVIOContext *s, uint64_t val)
406 avio_wl32(s, (uint32_t)(val & 0xffffffff));
407 avio_wl32(s, (uint32_t)(val >> 32));
410 void avio_wb64(AVIOContext *s, uint64_t val)
412 avio_wb32(s, (uint32_t)(val >> 32));
413 avio_wb32(s, (uint32_t)(val & 0xffffffff));
416 void avio_wl16(AVIOContext *s, unsigned int val)
418 avio_w8(s, (uint8_t)val);
419 avio_w8(s, (int)val >> 8);
422 void avio_wb16(AVIOContext *s, unsigned int val)
424 avio_w8(s, (int)val >> 8);
425 avio_w8(s, (uint8_t)val);
428 void avio_wl24(AVIOContext *s, unsigned int val)
430 avio_wl16(s, val & 0xffff);
431 avio_w8(s, (int)val >> 16);
434 void avio_wb24(AVIOContext *s, unsigned int val)
436 avio_wb16(s, (int)val >> 8);
437 avio_w8(s, (uint8_t)val);
442 static void fill_buffer(AVIOContext *s)
444 int max_buffer_size = s->max_packet_size ?
445 s->max_packet_size : IO_BUFFER_SIZE;
446 uint8_t *dst = s->buf_end - s->buffer + max_buffer_size < s->buffer_size ?
447 s->buf_end : s->buffer;
448 int len = s->buffer_size - (dst - s->buffer);
450 /* can't fill the buffer without read_packet, just set EOF if appropriate */
451 if (!s->read_packet && s->buf_ptr >= s->buf_end)
454 /* no need to do anything if EOF already reached */
458 if (s->update_checksum && dst == s->buffer) {
459 if (s->buf_end > s->checksum_ptr)
460 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
461 s->buf_end - s->checksum_ptr);
462 s->checksum_ptr = s->buffer;
465 /* make buffer smaller in case it ended up large after probing */
466 if (s->read_packet && s->orig_buffer_size && s->buffer_size > s->orig_buffer_size) {
467 if (dst == s->buffer) {
468 ffio_set_buf_size(s, s->orig_buffer_size);
470 s->checksum_ptr = dst = s->buffer;
472 av_assert0(len >= s->orig_buffer_size);
473 len = s->orig_buffer_size;
477 len = s->read_packet(s->opaque, dst, len);
481 /* do not modify buffer if EOF reached so that a seek back can
482 be done without rereading data */
489 s->buf_end = dst + len;
490 s->bytes_read += len;
494 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
497 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
500 unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf,
503 return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len);
506 unsigned long ffio_get_checksum(AVIOContext *s)
508 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
509 s->buf_ptr - s->checksum_ptr);
510 s->update_checksum = NULL;
514 void ffio_init_checksum(AVIOContext *s,
515 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
516 unsigned long checksum)
518 s->update_checksum = update_checksum;
519 if (s->update_checksum) {
520 s->checksum = checksum;
521 s->checksum_ptr = s->buf_ptr;
525 /* XXX: put an inline version */
526 int avio_r8(AVIOContext *s)
528 if (s->buf_ptr >= s->buf_end)
530 if (s->buf_ptr < s->buf_end)
531 return *s->buf_ptr++;
535 int avio_read(AVIOContext *s, unsigned char *buf, int size)
541 len = s->buf_end - s->buf_ptr;
544 if (len == 0 || s->write_flag) {
545 if((s->direct || size > s->buffer_size) && !s->update_checksum){
547 len = s->read_packet(s->opaque, buf, size);
549 /* do not modify buffer if EOF reached so that a seek back can
550 be done without rereading data */
557 s->bytes_read += len;
560 s->buf_ptr = s->buffer;
561 s->buf_end = s->buffer/* + len*/;
565 len = s->buf_end - s->buf_ptr;
570 memcpy(buf, s->buf_ptr, len);
577 if (s->error) return s->error;
578 if (avio_feof(s)) return AVERROR_EOF;
583 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
585 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
591 return avio_read(s, buf, size);
595 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
602 if (s->read_packet && s->write_flag) {
603 len = s->read_packet(s->opaque, buf, size);
609 len = s->buf_end - s->buf_ptr;
611 /* Reset the buf_end pointer to the start of the buffer, to make sure
612 * the fill_buffer call tries to read as much data as fits into the
613 * full buffer, instead of just what space is left after buf_end.
614 * This avoids returning partial packets at the end of the buffer,
615 * for packet based inputs.
617 s->buf_end = s->buf_ptr = s->buffer;
619 len = s->buf_end - s->buf_ptr;
623 memcpy(buf, s->buf_ptr, len);
626 if (s->error) return s->error;
627 if (avio_feof(s)) return AVERROR_EOF;
632 unsigned int avio_rl16(AVIOContext *s)
636 val |= avio_r8(s) << 8;
640 unsigned int avio_rl24(AVIOContext *s)
644 val |= avio_r8(s) << 16;
648 unsigned int avio_rl32(AVIOContext *s)
652 val |= avio_rl16(s) << 16;
656 uint64_t avio_rl64(AVIOContext *s)
659 val = (uint64_t)avio_rl32(s);
660 val |= (uint64_t)avio_rl32(s) << 32;
664 unsigned int avio_rb16(AVIOContext *s)
667 val = avio_r8(s) << 8;
672 unsigned int avio_rb24(AVIOContext *s)
675 val = avio_rb16(s) << 8;
679 unsigned int avio_rb32(AVIOContext *s)
682 val = avio_rb16(s) << 16;
687 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
694 if (c && i < maxlen-1)
696 } while (c != '\n' && c != '\r' && c);
697 if (c == '\r' && avio_r8(s) != '\n' && !avio_feof(s))
704 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
709 return AVERROR(EINVAL);
710 // reserve 1 byte for terminating 0
711 buflen = FFMIN(buflen - 1, maxlen);
712 for (i = 0; i < buflen; i++)
713 if (!(buf[i] = avio_r8(s)))
716 for (; i < maxlen; i++)
722 #define GET_STR16(type, read) \
723 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
728 return AVERROR(EINVAL); \
729 while (ret + 1 < maxlen) {\
732 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
735 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
741 GET_STR16(le, avio_rl16)
742 GET_STR16(be, avio_rb16)
746 uint64_t avio_rb64(AVIOContext *s)
749 val = (uint64_t)avio_rb32(s) << 32;
750 val |= (uint64_t)avio_rb32(s);
754 uint64_t ffio_read_varlen(AVIOContext *bc){
760 val= (val<<7) + (tmp&127);
765 int ffio_fdopen(AVIOContext **s, URLContext *h)
768 int buffer_size, max_packet_size;
770 max_packet_size = h->max_packet_size;
771 if (max_packet_size) {
772 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
774 buffer_size = IO_BUFFER_SIZE;
776 buffer = av_malloc(buffer_size);
778 return AVERROR(ENOMEM);
780 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
781 (int (*)(void *, uint8_t *, int)) ffurl_read,
782 (int (*)(void *, uint8_t *, int)) ffurl_write,
783 (int64_t (*)(void *, int64_t, int)) ffurl_seek);
786 return AVERROR(ENOMEM);
788 (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
789 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
790 (*s)->max_packet_size = max_packet_size;
792 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
793 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
795 (*s)->av_class = &ff_avio_class;
799 int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
802 int max_buffer_size = s->max_packet_size ?
803 s->max_packet_size : IO_BUFFER_SIZE;
804 int filled = s->buf_end - s->buffer;
806 buf_size += s->buf_ptr - s->buffer + max_buffer_size;
808 if (buf_size < filled || s->seekable)
810 av_assert0(!s->write_flag);
812 buffer = av_malloc(buf_size);
814 return AVERROR(ENOMEM);
816 memcpy(buffer, s->buffer, filled);
818 s->buf_ptr = buffer + (s->buf_ptr - s->buffer);
819 s->buf_end = buffer + (s->buf_end - s->buffer);
821 s->buffer_size = buf_size;
825 int ffio_set_buf_size(AVIOContext *s, int buf_size)
828 buffer = av_malloc(buf_size);
830 return AVERROR(ENOMEM);
834 s->orig_buffer_size =
835 s->buffer_size = buf_size;
837 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
841 static int url_resetbuf(AVIOContext *s, int flags)
843 av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
845 if (flags & AVIO_FLAG_WRITE) {
846 s->buf_end = s->buffer + s->buffer_size;
849 s->buf_end = s->buffer;
855 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
857 int64_t buffer_start;
859 int overlap, new_size, alloc_size;
860 uint8_t *buf = *bufp;
864 return AVERROR(EINVAL);
867 buffer_size = s->buf_end - s->buffer;
869 /* the buffers must touch or overlap */
870 if ((buffer_start = s->pos - buffer_size) > buf_size) {
872 return AVERROR(EINVAL);
875 overlap = buf_size - buffer_start;
876 new_size = buf_size + buffer_size - overlap;
878 alloc_size = FFMAX(s->buffer_size, new_size);
879 if (alloc_size > buf_size)
880 if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
881 return AVERROR(ENOMEM);
883 if (new_size > buf_size) {
884 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
889 s->buf_ptr = s->buffer = buf;
890 s->buffer_size = alloc_size;
892 s->buf_end = s->buf_ptr + buf_size;
899 int avio_open(AVIOContext **s, const char *filename, int flags)
901 return avio_open2(s, filename, flags, NULL, NULL);
904 int avio_open2(AVIOContext **s, const char *filename, int flags,
905 const AVIOInterruptCB *int_cb, AVDictionary **options)
910 err = ffurl_open(&h, filename, flags, int_cb, options);
913 err = ffio_fdopen(s, h);
921 int avio_close(AVIOContext *s)
930 av_freep(&s->buffer);
932 av_log(s, AV_LOG_DEBUG, "Statistics: %d seeks, %d writeouts\n", s->seek_count, s->writeout_count);
934 av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
936 return ffurl_close(h);
939 int avio_closep(AVIOContext **s)
941 int ret = avio_close(*s);
946 int avio_printf(AVIOContext *s, const char *fmt, ...)
953 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
955 avio_write(s, buf, strlen(buf));
959 int avio_pause(AVIOContext *s, int pause)
962 return AVERROR(ENOSYS);
963 return s->read_pause(s->opaque, pause);
966 int64_t avio_seek_time(AVIOContext *s, int stream_index,
967 int64_t timestamp, int flags)
969 URLContext *h = s->opaque;
972 return AVERROR(ENOSYS);
973 ret = s->read_seek(h, stream_index, timestamp, flags);
976 s->buf_ptr = s->buf_end; // Flush buffer
977 pos = s->seek(h, 0, SEEK_CUR);
980 else if (pos != AVERROR(ENOSYS))
986 int avio_read_to_bprint(AVIOContext *h, AVBPrint *pb, size_t max_size)
991 ret = avio_read(h, buf, FFMIN(max_size, sizeof(buf)));
992 if (ret == AVERROR_EOF)
996 av_bprint_append_data(pb, buf, ret);
997 if (!av_bprint_is_complete(pb))
998 return AVERROR(ENOMEM);
1004 /* output in a dynamic buffer */
1006 typedef struct DynBuffer {
1007 int pos, size, allocated_size;
1010 uint8_t io_buffer[1];
1013 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1015 DynBuffer *d = opaque;
1016 unsigned new_size, new_allocated_size;
1018 /* reallocate buffer if needed */
1019 new_size = d->pos + buf_size;
1020 new_allocated_size = d->allocated_size;
1021 if (new_size < d->pos || new_size > INT_MAX/2)
1023 while (new_size > new_allocated_size) {
1024 if (!new_allocated_size)
1025 new_allocated_size = new_size;
1027 new_allocated_size += new_allocated_size / 2 + 1;
1030 if (new_allocated_size > d->allocated_size) {
1032 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
1033 d->allocated_size = 0;
1037 d->allocated_size = new_allocated_size;
1039 memcpy(d->buffer + d->pos, buf, buf_size);
1041 if (d->pos > d->size)
1046 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1048 unsigned char buf1[4];
1051 /* packetized write: output the header */
1052 AV_WB32(buf1, buf_size);
1053 ret = dyn_buf_write(opaque, buf1, 4);
1058 return dyn_buf_write(opaque, buf, buf_size);
1061 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1063 DynBuffer *d = opaque;
1065 if (whence == SEEK_CUR)
1067 else if (whence == SEEK_END)
1069 if (offset < 0 || offset > 0x7fffffffLL)
1075 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1078 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1080 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1082 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1084 return AVERROR(ENOMEM);
1085 d->io_buffer_size = io_buffer_size;
1086 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1087 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1088 max_packet_size ? NULL : dyn_buf_seek);
1091 return AVERROR(ENOMEM);
1093 (*s)->max_packet_size = max_packet_size;
1097 int avio_open_dyn_buf(AVIOContext **s)
1099 return url_open_dyn_buf_internal(s, 0);
1102 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1104 if (max_packet_size <= 0)
1106 return url_open_dyn_buf_internal(s, max_packet_size);
1109 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1113 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1121 /* don't attempt to pad fixed-size packet buffers */
1122 if (!s->max_packet_size) {
1123 avio_write(s, padbuf, sizeof(padbuf));
1124 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1130 *pbuffer = d->buffer;
1134 return size - padding;
1137 void ffio_free_dyn_buf(AVIOContext **s)
1142 avio_close_dyn_buf(*s, &tmp);
1147 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1149 DynBuffer *d = opaque;
1152 if (d->pos > d->size)
1157 int ffio_open_null_buf(AVIOContext **s)
1159 int ret = url_open_dyn_buf_internal(s, 0);
1161 AVIOContext *pb = *s;
1162 pb->write_packet = null_buf_write;
1167 int ffio_close_null_buf(AVIOContext *s)
1169 DynBuffer *d = s->opaque;