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/dict.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/log.h"
26 #include "libavutil/opt.h"
29 #include "avio_internal.h"
34 #define IO_BUFFER_SIZE 32768
37 * Do seeks within this distance ahead of the current buffer by skipping
38 * data instead of calling the protocol seek function, for seekable
41 #define SHORT_SEEK_THRESHOLD 4096
43 typedef struct AVIOInternal {
46 char *protocol_whitelist;
47 char *protocol_blacklist;
50 const URLProtocol **protocols;
53 static void *io_priv_child_next(void *obj, void *prev)
55 AVIOInternal *internal = obj;
56 return prev ? NULL : internal->h;
59 static const AVClass *io_priv_child_class_next(const AVClass *prev)
61 return prev ? NULL : &ffurl_context_class;
64 #define OFFSET(x) offsetof(AVIOInternal, x)
65 static const AVOption io_priv_options[] = {
66 { "protocol_whitelist", "A comma-separated list of allowed protocols",
67 OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING },
68 { "protocol_blacklist", "A comma-separated list of forbidden protocols",
69 OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING },
73 static const AVClass io_priv_class = {
74 .class_name = "AVIOContext",
75 .item_name = av_default_item_name,
76 .version = LIBAVUTIL_VERSION_INT,
77 .option = io_priv_options,
78 .child_next = io_priv_child_next,
79 .child_class_next = io_priv_child_class_next,
82 static void *ff_avio_child_next(void *obj, void *prev)
85 return prev ? NULL : s->opaque;
88 static const AVClass *ff_avio_child_class_next(const AVClass *prev)
90 return prev ? NULL : &io_priv_class;
93 static const AVOption ff_avio_options[] = {
97 const AVClass ff_avio_class = {
98 .class_name = "AVIOContext",
99 .item_name = av_default_item_name,
100 .version = LIBAVUTIL_VERSION_INT,
101 .option = ff_avio_options,
102 .child_next = ff_avio_child_next,
103 .child_class_next = ff_avio_child_class_next,
106 static void fill_buffer(AVIOContext *s);
107 static int url_resetbuf(AVIOContext *s, int flags);
109 int ffio_init_context(AVIOContext *s,
110 unsigned char *buffer,
114 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
115 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
116 int64_t (*seek)(void *opaque, int64_t offset, int whence))
119 s->buffer_size = buffer_size;
123 url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
125 s->write_packet = write_packet;
126 s->read_packet = read_packet;
132 s->seekable = seek ? AVIO_SEEKABLE_NORMAL : 0;
133 s->max_packet_size = 0;
134 s->update_checksum = NULL;
136 if (!read_packet && !write_flag) {
137 s->pos = buffer_size;
138 s->buf_end = s->buffer + buffer_size;
140 s->read_pause = NULL;
143 s->write_data_type = NULL;
144 s->ignore_boundary_point = 0;
145 s->current_type = AVIO_DATA_MARKER_UNKNOWN;
146 s->last_time = AV_NOPTS_VALUE;
151 AVIOContext *avio_alloc_context(
152 unsigned char *buffer,
156 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
157 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
158 int64_t (*seek)(void *opaque, int64_t offset, int whence))
160 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
163 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
164 read_packet, write_packet, seek);
168 static void flush_buffer(AVIOContext *s)
170 if (s->buf_ptr > s->buffer) {
171 int size = s->buf_ptr - s->buffer;
174 if (s->write_data_type)
175 ret = s->write_data_type(s->opaque, s->buffer,
179 else if (s->write_packet)
180 ret = s->write_packet(s->opaque, s->buffer,
185 if (s->pos + size > s->written)
186 s->written = s->pos + size;
189 if (s->current_type == AVIO_DATA_MARKER_SYNC_POINT ||
190 s->current_type == AVIO_DATA_MARKER_BOUNDARY_POINT) {
191 s->current_type = AVIO_DATA_MARKER_UNKNOWN;
193 s->last_time = AV_NOPTS_VALUE;
194 if (s->update_checksum) {
195 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
196 s->buf_ptr - s->checksum_ptr);
197 s->checksum_ptr = s->buffer;
201 s->buf_ptr = s->buffer;
204 void avio_w8(AVIOContext *s, int b)
207 if (s->buf_ptr >= s->buf_end)
211 void ffio_fill(AVIOContext *s, int b, int count)
214 int len = FFMIN(s->buf_end - s->buf_ptr, count);
215 memset(s->buf_ptr, b, len);
218 if (s->buf_ptr >= s->buf_end)
225 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
228 int len = FFMIN(s->buf_end - s->buf_ptr, size);
229 memcpy(s->buf_ptr, buf, len);
232 if (s->buf_ptr >= s->buf_end)
240 void avio_flush(AVIOContext *s)
246 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
250 int force = whence & AVSEEK_FORCE;
251 whence &= ~AVSEEK_FORCE;
254 return AVERROR(EINVAL);
256 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
258 if (whence != SEEK_CUR && whence != SEEK_SET)
259 return AVERROR(EINVAL);
261 if (whence == SEEK_CUR) {
262 offset1 = pos + (s->buf_ptr - s->buffer);
267 offset1 = offset - pos;
268 if (!s->must_flush &&
269 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
270 /* can do the seek inside the buffer */
271 s->buf_ptr = s->buffer + offset1;
272 } else if ((!(s->seekable & AVIO_SEEKABLE_NORMAL) ||
273 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
274 !s->write_flag && offset1 >= 0 &&
275 (whence != SEEK_END || force)) {
276 while(s->pos < offset && !s->eof_reached)
280 s->buf_ptr = s->buf_end + offset - s->pos;
289 return AVERROR(EPIPE);
290 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
293 s->buf_end = s->buffer;
294 s->buf_ptr = s->buffer;
301 int64_t avio_size(AVIOContext *s)
306 return AVERROR(EINVAL);
312 return AVERROR(ENOSYS);
313 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
315 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
318 s->seek(s->opaque, s->pos, SEEK_SET);
323 void avio_wl32(AVIOContext *s, unsigned int val)
326 avio_w8(s, val >> 8);
327 avio_w8(s, val >> 16);
328 avio_w8(s, val >> 24);
331 void avio_wb32(AVIOContext *s, unsigned int val)
333 avio_w8(s, val >> 24);
334 avio_w8(s, val >> 16);
335 avio_w8(s, val >> 8);
339 int avio_put_str(AVIOContext *s, const char *str)
344 avio_write(s, (const unsigned char *) str, len);
350 #define PUT_STR16(type, write) \
351 int avio_put_str16 ## type(AVIOContext * s, const char *str) \
353 const uint8_t *q = str; \
360 GET_UTF8(ch, *q++, break; ) \
361 PUT_UTF16(ch, tmp, write(s, tmp); ret += 2; ) \
368 PUT_STR16(le, avio_wl16)
369 PUT_STR16(be, avio_wb16)
373 int ff_get_v_length(uint64_t val)
383 void ff_put_v(AVIOContext *bc, uint64_t val)
385 int i = ff_get_v_length(val);
388 avio_w8(bc, 128 | (val >> (7 * i)));
390 avio_w8(bc, val & 127);
393 void avio_wl64(AVIOContext *s, uint64_t val)
395 avio_wl32(s, (uint32_t)(val & 0xffffffff));
396 avio_wl32(s, (uint32_t)(val >> 32));
399 void avio_wb64(AVIOContext *s, uint64_t val)
401 avio_wb32(s, (uint32_t)(val >> 32));
402 avio_wb32(s, (uint32_t)(val & 0xffffffff));
405 void avio_wl16(AVIOContext *s, unsigned int val)
408 avio_w8(s, val >> 8);
411 void avio_wb16(AVIOContext *s, unsigned int val)
413 avio_w8(s, val >> 8);
417 void avio_wl24(AVIOContext *s, unsigned int val)
419 avio_wl16(s, val & 0xffff);
420 avio_w8(s, val >> 16);
423 void avio_wb24(AVIOContext *s, unsigned int val)
425 avio_wb16(s, val >> 8);
429 void avio_write_marker(AVIOContext *s, int64_t time, enum AVIODataMarkerType type)
431 if (!s->write_data_type)
433 // If ignoring boundary points, just treat it as unknown
434 if (type == AVIO_DATA_MARKER_BOUNDARY_POINT && s->ignore_boundary_point)
435 type = AVIO_DATA_MARKER_UNKNOWN;
436 // Avoid unnecessary flushes if we are already in non-header/trailer
437 // data and setting the type to unknown
438 if (type == AVIO_DATA_MARKER_UNKNOWN &&
439 (s->current_type != AVIO_DATA_MARKER_HEADER &&
440 s->current_type != AVIO_DATA_MARKER_TRAILER))
444 case AVIO_DATA_MARKER_HEADER:
445 case AVIO_DATA_MARKER_TRAILER:
446 // For header/trailer, ignore a new marker of the same type;
447 // consecutive header/trailer markers can be merged.
448 if (type == s->current_type)
453 // If we've reached here, we have a new, noteworthy marker.
454 // Flush the previous data and mark the start of the new data.
456 s->current_type = type;
462 static void fill_buffer(AVIOContext *s)
464 uint8_t *dst = !s->max_packet_size &&
465 s->buf_end - s->buffer < s->buffer_size ?
466 s->buf_end : s->buffer;
467 int len = s->buffer_size - (dst - s->buffer);
468 int max_buffer_size = s->max_packet_size ?
469 s->max_packet_size : IO_BUFFER_SIZE;
471 /* can't fill the buffer without read_packet, just set EOF if appropriate */
472 if (!s->read_packet && s->buf_ptr >= s->buf_end)
475 /* no need to do anything if EOF already reached */
479 if (s->update_checksum && dst == s->buffer) {
480 if (s->buf_end > s->checksum_ptr)
481 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
482 s->buf_end - s->checksum_ptr);
483 s->checksum_ptr = s->buffer;
486 /* make buffer smaller in case it ended up large after probing */
487 if (s->buffer_size > max_buffer_size) {
488 ffio_set_buf_size(s, max_buffer_size);
490 s->checksum_ptr = dst = s->buffer;
491 len = s->buffer_size;
495 len = s->read_packet(s->opaque, dst, len);
499 /* do not modify buffer if EOF reached so that a seek back can
500 be done without rereading data */
507 s->buf_end = dst + len;
511 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
514 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
517 unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf,
520 return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len);
523 unsigned long ffio_get_checksum(AVIOContext *s)
525 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
526 s->buf_ptr - s->checksum_ptr);
527 s->update_checksum = NULL;
531 void ffio_init_checksum(AVIOContext *s,
532 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
533 unsigned long checksum)
535 s->update_checksum = update_checksum;
536 if (s->update_checksum) {
537 s->checksum = checksum;
538 s->checksum_ptr = s->buf_ptr;
542 /* XXX: put an inline version */
543 int avio_r8(AVIOContext *s)
545 if (s->buf_ptr >= s->buf_end)
547 if (s->buf_ptr < s->buf_end)
548 return *s->buf_ptr++;
552 int avio_read(AVIOContext *s, unsigned char *buf, int size)
558 len = s->buf_end - s->buf_ptr;
561 if (len == 0 || s->write_flag) {
562 if(size > s->buffer_size && !s->update_checksum){
564 len = s->read_packet(s->opaque, buf, size);
566 /* do not modify buffer if EOF reached so that a seek back can
567 be done without rereading data */
576 s->buf_ptr = s->buffer;
577 s->buf_end = s->buffer/* + len*/;
581 len = s->buf_end - s->buf_ptr;
586 memcpy(buf, s->buf_ptr, len);
593 if (s->error) return s->error;
594 if (s->eof_reached) return AVERROR_EOF;
599 int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
601 int ret = avio_read(s, buf, size);
603 return AVERROR_INVALIDDATA;
607 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
609 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
615 return avio_read(s, buf, size);
619 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
626 if (s->read_packet && s->write_flag) {
627 len = s->read_packet(s->opaque, buf, size);
633 len = s->buf_end - s->buf_ptr;
635 /* Reset the buf_end pointer to the start of the buffer, to make sure
636 * the fill_buffer call tries to read as much data as fits into the
637 * full buffer, instead of just what space is left after buf_end.
638 * This avoids returning partial packets at the end of the buffer,
639 * for packet based inputs.
641 s->buf_end = s->buf_ptr = s->buffer;
643 len = s->buf_end - s->buf_ptr;
647 memcpy(buf, s->buf_ptr, len);
650 if (s->error) return s->error;
651 if (s->eof_reached) return AVERROR_EOF;
656 unsigned int avio_rl16(AVIOContext *s)
660 val |= avio_r8(s) << 8;
664 unsigned int avio_rl24(AVIOContext *s)
668 val |= avio_r8(s) << 16;
672 unsigned int avio_rl32(AVIOContext *s)
676 val |= avio_rl16(s) << 16;
680 uint64_t avio_rl64(AVIOContext *s)
683 val = (uint64_t)avio_rl32(s);
684 val |= (uint64_t)avio_rl32(s) << 32;
688 unsigned int avio_rb16(AVIOContext *s)
691 val = avio_r8(s) << 8;
696 unsigned int avio_rb24(AVIOContext *s)
699 val = avio_rb16(s) << 8;
703 unsigned int avio_rb32(AVIOContext *s)
706 val = avio_rb16(s) << 16;
711 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
718 if (c && i < maxlen-1)
720 } while (c != '\n' && c);
726 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
731 return AVERROR(EINVAL);
732 // reserve 1 byte for terminating 0
733 buflen = FFMIN(buflen - 1, maxlen);
734 for (i = 0; i < buflen; i++)
735 if (!(buf[i] = avio_r8(s)))
738 for (; i < maxlen; i++)
744 #define GET_STR16(type, read) \
745 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
750 return AVERROR(EINVAL); \
751 while (ret + 1 < maxlen) {\
754 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
757 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
763 GET_STR16(le, avio_rl16)
764 GET_STR16(be, avio_rb16)
768 uint64_t avio_rb64(AVIOContext *s)
771 val = (uint64_t)avio_rb32(s) << 32;
772 val |= (uint64_t)avio_rb32(s);
776 uint64_t ffio_read_varlen(AVIOContext *bc){
782 val= (val<<7) + (tmp&127);
787 static int io_read_packet(void *opaque, uint8_t *buf, int buf_size)
789 AVIOInternal *internal = opaque;
790 return ffurl_read(internal->h, buf, buf_size);
793 static int io_write_packet(void *opaque, uint8_t *buf, int buf_size)
795 AVIOInternal *internal = opaque;
796 return ffurl_write(internal->h, buf, buf_size);
799 static int64_t io_seek(void *opaque, int64_t offset, int whence)
801 AVIOInternal *internal = opaque;
802 return ffurl_seek(internal->h, offset, whence);
805 static int io_read_pause(void *opaque, int pause)
807 AVIOInternal *internal = opaque;
808 if (!internal->h->prot->url_read_pause)
809 return AVERROR(ENOSYS);
810 return internal->h->prot->url_read_pause(internal->h, pause);
813 static int64_t io_read_seek(void *opaque, int stream_index, int64_t timestamp, int flags)
815 AVIOInternal *internal = opaque;
816 if (!internal->h->prot->url_read_seek)
817 return AVERROR(ENOSYS);
818 return internal->h->prot->url_read_seek(internal->h, stream_index, timestamp, flags);
821 int ffio_fdopen(AVIOContext **s, URLContext *h)
823 AVIOInternal *internal = NULL;
824 uint8_t *buffer = NULL;
825 int buffer_size, max_packet_size;
827 max_packet_size = h->max_packet_size;
828 if (max_packet_size) {
829 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
831 buffer_size = IO_BUFFER_SIZE;
833 buffer = av_malloc(buffer_size);
835 return AVERROR(ENOMEM);
837 internal = av_mallocz(sizeof(*internal));
841 internal->class = &io_priv_class;
844 av_opt_set_defaults(internal);
846 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE,
847 internal, io_read_packet, io_write_packet, io_seek);
851 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
852 (*s)->max_packet_size = max_packet_size;
854 (*s)->read_pause = io_read_pause;
855 (*s)->read_seek = io_read_seek;
857 if (h->prot->url_read_seek)
858 (*s)->seekable |= AVIO_SEEKABLE_TIME;
860 (*s)->av_class = &ff_avio_class;
864 av_opt_free(internal);
867 return AVERROR(ENOMEM);
870 int ffio_set_buf_size(AVIOContext *s, int buf_size)
873 buffer = av_malloc(buf_size);
875 return AVERROR(ENOMEM);
879 s->buffer_size = buf_size;
881 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
885 static int url_resetbuf(AVIOContext *s, int flags)
887 assert(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
889 if (flags & AVIO_FLAG_WRITE) {
890 s->buf_end = s->buffer + s->buffer_size;
893 s->buf_end = s->buffer;
899 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
901 int64_t buffer_start;
903 int overlap, new_size, alloc_size;
906 return AVERROR(EINVAL);
908 buffer_size = s->buf_end - s->buffer;
910 /* the buffers must touch or overlap */
911 if ((buffer_start = s->pos - buffer_size) > buf_size)
912 return AVERROR(EINVAL);
914 overlap = buf_size - buffer_start;
915 new_size = buf_size + buffer_size - overlap;
917 alloc_size = FFMAX(s->buffer_size, new_size);
918 if (alloc_size > buf_size)
919 if (!(buf = av_realloc(buf, alloc_size)))
920 return AVERROR(ENOMEM);
922 if (new_size > buf_size) {
923 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
928 s->buf_ptr = s->buffer = buf;
929 s->buffer_size = alloc_size;
931 s->buf_end = s->buf_ptr + buf_size;
938 int avio_open(AVIOContext **s, const char *filename, int flags)
940 return avio_open2(s, filename, flags, NULL, NULL);
943 int avio_open2(AVIOContext **s, const char *filename, int flags,
944 const AVIOInterruptCB *int_cb, AVDictionary **options)
946 AVIOInternal *internal;
947 const URLProtocol **protocols;
948 char *proto_whitelist = NULL, *proto_blacklist = NULL;
949 AVDictionaryEntry *e;
954 e = av_dict_get(*options, "protocol_whitelist", NULL, 0);
956 proto_whitelist = e->value;
957 e = av_dict_get(*options, "protocol_blacklist", NULL, 0);
959 proto_blacklist = e->value;
962 protocols = ffurl_get_protocols(proto_whitelist, proto_blacklist);
964 return AVERROR(ENOMEM);
966 err = ffurl_open(&h, filename, flags, int_cb, options, protocols, NULL);
968 av_freep(&protocols);
972 err = ffio_fdopen(s, h);
975 av_freep(&protocols);
979 internal = (*s)->opaque;
980 internal->protocols = protocols;
983 err = av_opt_set_dict(internal, options);
993 int avio_close(AVIOContext *s)
995 AVIOInternal *internal;
1002 internal = s->opaque;
1005 av_opt_free(internal);
1007 av_freep(&internal->protocols);
1008 av_freep(&s->opaque);
1009 av_freep(&s->buffer);
1011 return ffurl_close(h);
1014 int avio_closep(AVIOContext **s)
1016 int ret = avio_close(*s);
1021 int avio_printf(AVIOContext *s, const char *fmt, ...)
1028 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
1030 avio_write(s, buf, strlen(buf));
1034 int avio_pause(AVIOContext *s, int pause)
1037 return AVERROR(ENOSYS);
1038 return s->read_pause(s->opaque, pause);
1041 int64_t avio_seek_time(AVIOContext *s, int stream_index,
1042 int64_t timestamp, int flags)
1046 return AVERROR(ENOSYS);
1047 ret = s->read_seek(s->opaque, stream_index, timestamp, flags);
1050 s->buf_ptr = s->buf_end; // Flush buffer
1051 pos = s->seek(s->opaque, 0, SEEK_CUR);
1054 else if (pos != AVERROR(ENOSYS))
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) {
1088 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
1089 d->allocated_size = 0;
1093 d->allocated_size = new_allocated_size;
1095 memcpy(d->buffer + d->pos, buf, buf_size);
1097 if (d->pos > d->size)
1102 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1104 unsigned char buf1[4];
1107 /* packetized write: output the header */
1108 AV_WB32(buf1, buf_size);
1109 ret = dyn_buf_write(opaque, buf1, 4);
1114 return dyn_buf_write(opaque, buf, buf_size);
1117 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1119 DynBuffer *d = opaque;
1121 if (whence == SEEK_CUR)
1123 else if (whence == SEEK_END)
1125 if (offset < 0 || offset > 0x7fffffffLL)
1131 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1134 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1136 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1138 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1140 return AVERROR(ENOMEM);
1141 d->io_buffer_size = io_buffer_size;
1142 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1143 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1144 max_packet_size ? NULL : dyn_buf_seek);
1147 return AVERROR(ENOMEM);
1149 (*s)->max_packet_size = max_packet_size;
1153 int avio_open_dyn_buf(AVIOContext **s)
1155 return url_open_dyn_buf_internal(s, 0);
1158 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1160 if (max_packet_size <= 0)
1162 return url_open_dyn_buf_internal(s, max_packet_size);
1165 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1169 static const char padbuf[AV_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 = AV_INPUT_BUFFER_PADDING_SIZE;
1186 *pbuffer = d->buffer;
1190 return size - padding;
1193 void ffio_free_dyn_buf(AVIOContext **s)
1198 avio_close_dyn_buf(*s, &tmp);
1203 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1205 DynBuffer *d = opaque;
1208 if (d->pos > d->size)
1213 int ffio_open_null_buf(AVIOContext **s)
1215 int ret = url_open_dyn_buf_internal(s, 0);
1217 AVIOContext *pb = *s;
1218 pb->write_packet = null_buf_write;
1223 int ffio_close_null_buf(AVIOContext *s)
1225 DynBuffer *d = s->opaque;