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 void avio_context_free(AVIOContext **ps)
173 static void flush_buffer(AVIOContext *s)
175 if (s->buf_ptr > s->buffer) {
176 int size = s->buf_ptr - s->buffer;
179 if (s->write_data_type)
180 ret = s->write_data_type(s->opaque, s->buffer,
184 else if (s->write_packet)
185 ret = s->write_packet(s->opaque, s->buffer,
190 if (s->pos + size > s->written)
191 s->written = s->pos + size;
194 if (s->current_type == AVIO_DATA_MARKER_SYNC_POINT ||
195 s->current_type == AVIO_DATA_MARKER_BOUNDARY_POINT) {
196 s->current_type = AVIO_DATA_MARKER_UNKNOWN;
198 s->last_time = AV_NOPTS_VALUE;
199 if (s->update_checksum) {
200 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
201 s->buf_ptr - s->checksum_ptr);
202 s->checksum_ptr = s->buffer;
206 s->buf_ptr = s->buffer;
209 void avio_w8(AVIOContext *s, int b)
212 if (s->buf_ptr >= s->buf_end)
216 void ffio_fill(AVIOContext *s, int b, int count)
219 int len = FFMIN(s->buf_end - s->buf_ptr, count);
220 memset(s->buf_ptr, b, len);
223 if (s->buf_ptr >= s->buf_end)
230 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
233 int len = FFMIN(s->buf_end - s->buf_ptr, size);
234 memcpy(s->buf_ptr, buf, len);
237 if (s->buf_ptr >= s->buf_end)
245 void avio_flush(AVIOContext *s)
251 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
255 int force = whence & AVSEEK_FORCE;
256 whence &= ~AVSEEK_FORCE;
259 return AVERROR(EINVAL);
261 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
263 if (whence != SEEK_CUR && whence != SEEK_SET)
264 return AVERROR(EINVAL);
266 if (whence == SEEK_CUR) {
267 offset1 = pos + (s->buf_ptr - s->buffer);
272 offset1 = offset - pos;
273 if (!s->must_flush &&
274 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
275 /* can do the seek inside the buffer */
276 s->buf_ptr = s->buffer + offset1;
277 } else if ((!(s->seekable & AVIO_SEEKABLE_NORMAL) ||
278 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
279 !s->write_flag && offset1 >= 0 &&
280 (whence != SEEK_END || force)) {
281 while(s->pos < offset && !s->eof_reached)
285 s->buf_ptr = s->buf_end + offset - s->pos;
294 return AVERROR(EPIPE);
295 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
298 s->buf_end = s->buffer;
299 s->buf_ptr = s->buffer;
306 int64_t avio_size(AVIOContext *s)
311 return AVERROR(EINVAL);
317 return AVERROR(ENOSYS);
318 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
320 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
323 s->seek(s->opaque, s->pos, SEEK_SET);
328 void avio_wl32(AVIOContext *s, unsigned int val)
331 avio_w8(s, val >> 8);
332 avio_w8(s, val >> 16);
333 avio_w8(s, val >> 24);
336 void avio_wb32(AVIOContext *s, unsigned int val)
338 avio_w8(s, val >> 24);
339 avio_w8(s, val >> 16);
340 avio_w8(s, val >> 8);
344 int avio_put_str(AVIOContext *s, const char *str)
349 avio_write(s, (const unsigned char *) str, len);
355 #define PUT_STR16(type, write) \
356 int avio_put_str16 ## type(AVIOContext * s, const char *str) \
358 const uint8_t *q = str; \
365 GET_UTF8(ch, *q++, break; ) \
366 PUT_UTF16(ch, tmp, write(s, tmp); ret += 2; ) \
373 PUT_STR16(le, avio_wl16)
374 PUT_STR16(be, avio_wb16)
378 int ff_get_v_length(uint64_t val)
388 void ff_put_v(AVIOContext *bc, uint64_t val)
390 int i = ff_get_v_length(val);
393 avio_w8(bc, 128 | (val >> (7 * i)));
395 avio_w8(bc, val & 127);
398 void avio_wl64(AVIOContext *s, uint64_t val)
400 avio_wl32(s, (uint32_t)(val & 0xffffffff));
401 avio_wl32(s, (uint32_t)(val >> 32));
404 void avio_wb64(AVIOContext *s, uint64_t val)
406 avio_wb32(s, (uint32_t)(val >> 32));
407 avio_wb32(s, (uint32_t)(val & 0xffffffff));
410 void avio_wl16(AVIOContext *s, unsigned int val)
413 avio_w8(s, val >> 8);
416 void avio_wb16(AVIOContext *s, unsigned int val)
418 avio_w8(s, val >> 8);
422 void avio_wl24(AVIOContext *s, unsigned int val)
424 avio_wl16(s, val & 0xffff);
425 avio_w8(s, val >> 16);
428 void avio_wb24(AVIOContext *s, unsigned int val)
430 avio_wb16(s, val >> 8);
434 void avio_write_marker(AVIOContext *s, int64_t time, enum AVIODataMarkerType type)
436 if (!s->write_data_type)
438 // If ignoring boundary points, just treat it as unknown
439 if (type == AVIO_DATA_MARKER_BOUNDARY_POINT && s->ignore_boundary_point)
440 type = AVIO_DATA_MARKER_UNKNOWN;
441 // Avoid unnecessary flushes if we are already in non-header/trailer
442 // data and setting the type to unknown
443 if (type == AVIO_DATA_MARKER_UNKNOWN &&
444 (s->current_type != AVIO_DATA_MARKER_HEADER &&
445 s->current_type != AVIO_DATA_MARKER_TRAILER))
449 case AVIO_DATA_MARKER_HEADER:
450 case AVIO_DATA_MARKER_TRAILER:
451 // For header/trailer, ignore a new marker of the same type;
452 // consecutive header/trailer markers can be merged.
453 if (type == s->current_type)
458 // If we've reached here, we have a new, noteworthy marker.
459 // Flush the previous data and mark the start of the new data.
461 s->current_type = type;
467 static void fill_buffer(AVIOContext *s)
469 uint8_t *dst = !s->max_packet_size &&
470 s->buf_end - s->buffer < s->buffer_size ?
471 s->buf_end : s->buffer;
472 int len = s->buffer_size - (dst - s->buffer);
473 int max_buffer_size = s->max_packet_size ?
474 s->max_packet_size : IO_BUFFER_SIZE;
476 /* can't fill the buffer without read_packet, just set EOF if appropriate */
477 if (!s->read_packet && s->buf_ptr >= s->buf_end)
480 /* no need to do anything if EOF already reached */
484 if (s->update_checksum && dst == s->buffer) {
485 if (s->buf_end > s->checksum_ptr)
486 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
487 s->buf_end - s->checksum_ptr);
488 s->checksum_ptr = s->buffer;
491 /* make buffer smaller in case it ended up large after probing */
492 if (s->buffer_size > max_buffer_size) {
493 ffio_set_buf_size(s, max_buffer_size);
495 s->checksum_ptr = dst = s->buffer;
496 len = s->buffer_size;
500 len = s->read_packet(s->opaque, dst, len);
504 /* do not modify buffer if EOF reached so that a seek back can
505 be done without rereading data */
512 s->buf_end = dst + len;
516 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
519 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
522 unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf,
525 return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len);
528 unsigned long ffio_get_checksum(AVIOContext *s)
530 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
531 s->buf_ptr - s->checksum_ptr);
532 s->update_checksum = NULL;
536 void ffio_init_checksum(AVIOContext *s,
537 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
538 unsigned long checksum)
540 s->update_checksum = update_checksum;
541 if (s->update_checksum) {
542 s->checksum = checksum;
543 s->checksum_ptr = s->buf_ptr;
547 /* XXX: put an inline version */
548 int avio_r8(AVIOContext *s)
550 if (s->buf_ptr >= s->buf_end)
552 if (s->buf_ptr < s->buf_end)
553 return *s->buf_ptr++;
557 int avio_read(AVIOContext *s, unsigned char *buf, int size)
563 len = s->buf_end - s->buf_ptr;
566 if (len == 0 || s->write_flag) {
567 if(size > s->buffer_size && !s->update_checksum){
569 len = s->read_packet(s->opaque, buf, size);
571 /* do not modify buffer if EOF reached so that a seek back can
572 be done without rereading data */
581 s->buf_ptr = s->buffer;
582 s->buf_end = s->buffer/* + len*/;
586 len = s->buf_end - s->buf_ptr;
591 memcpy(buf, s->buf_ptr, len);
598 if (s->error) return s->error;
599 if (s->eof_reached) return AVERROR_EOF;
604 int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
606 int ret = avio_read(s, buf, size);
608 return AVERROR_INVALIDDATA;
612 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
614 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
620 return avio_read(s, buf, size);
624 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
631 if (s->read_packet && s->write_flag) {
632 len = s->read_packet(s->opaque, buf, size);
638 len = s->buf_end - s->buf_ptr;
640 /* Reset the buf_end pointer to the start of the buffer, to make sure
641 * the fill_buffer call tries to read as much data as fits into the
642 * full buffer, instead of just what space is left after buf_end.
643 * This avoids returning partial packets at the end of the buffer,
644 * for packet based inputs.
646 s->buf_end = s->buf_ptr = s->buffer;
648 len = s->buf_end - s->buf_ptr;
652 memcpy(buf, s->buf_ptr, len);
655 if (s->error) return s->error;
656 if (s->eof_reached) return AVERROR_EOF;
661 unsigned int avio_rl16(AVIOContext *s)
665 val |= avio_r8(s) << 8;
669 unsigned int avio_rl24(AVIOContext *s)
673 val |= avio_r8(s) << 16;
677 unsigned int avio_rl32(AVIOContext *s)
681 val |= avio_rl16(s) << 16;
685 uint64_t avio_rl64(AVIOContext *s)
688 val = (uint64_t)avio_rl32(s);
689 val |= (uint64_t)avio_rl32(s) << 32;
693 unsigned int avio_rb16(AVIOContext *s)
696 val = avio_r8(s) << 8;
701 unsigned int avio_rb24(AVIOContext *s)
704 val = avio_rb16(s) << 8;
708 unsigned int avio_rb32(AVIOContext *s)
711 val = avio_rb16(s) << 16;
716 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
723 if (c && i < maxlen-1)
725 } while (c != '\n' && c);
731 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
736 return AVERROR(EINVAL);
737 // reserve 1 byte for terminating 0
738 buflen = FFMIN(buflen - 1, maxlen);
739 for (i = 0; i < buflen; i++)
740 if (!(buf[i] = avio_r8(s)))
743 for (; i < maxlen; i++)
749 #define GET_STR16(type, read) \
750 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
755 return AVERROR(EINVAL); \
756 while (ret + 1 < maxlen) {\
759 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
762 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
768 GET_STR16(le, avio_rl16)
769 GET_STR16(be, avio_rb16)
773 uint64_t avio_rb64(AVIOContext *s)
776 val = (uint64_t)avio_rb32(s) << 32;
777 val |= (uint64_t)avio_rb32(s);
781 uint64_t ffio_read_varlen(AVIOContext *bc){
787 val= (val<<7) + (tmp&127);
792 static int io_read_packet(void *opaque, uint8_t *buf, int buf_size)
794 AVIOInternal *internal = opaque;
795 return ffurl_read(internal->h, buf, buf_size);
798 static int io_write_packet(void *opaque, uint8_t *buf, int buf_size)
800 AVIOInternal *internal = opaque;
801 return ffurl_write(internal->h, buf, buf_size);
804 static int64_t io_seek(void *opaque, int64_t offset, int whence)
806 AVIOInternal *internal = opaque;
807 return ffurl_seek(internal->h, offset, whence);
810 static int io_read_pause(void *opaque, int pause)
812 AVIOInternal *internal = opaque;
813 if (!internal->h->prot->url_read_pause)
814 return AVERROR(ENOSYS);
815 return internal->h->prot->url_read_pause(internal->h, pause);
818 static int64_t io_read_seek(void *opaque, int stream_index, int64_t timestamp, int flags)
820 AVIOInternal *internal = opaque;
821 if (!internal->h->prot->url_read_seek)
822 return AVERROR(ENOSYS);
823 return internal->h->prot->url_read_seek(internal->h, stream_index, timestamp, flags);
826 int ffio_fdopen(AVIOContext **s, URLContext *h)
828 AVIOInternal *internal = NULL;
829 uint8_t *buffer = NULL;
830 int buffer_size, max_packet_size;
832 max_packet_size = h->max_packet_size;
833 if (max_packet_size) {
834 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
836 buffer_size = IO_BUFFER_SIZE;
838 buffer = av_malloc(buffer_size);
840 return AVERROR(ENOMEM);
842 internal = av_mallocz(sizeof(*internal));
846 internal->class = &io_priv_class;
849 av_opt_set_defaults(internal);
851 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE,
852 internal, io_read_packet, io_write_packet, io_seek);
856 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
857 (*s)->max_packet_size = max_packet_size;
859 (*s)->read_pause = io_read_pause;
860 (*s)->read_seek = io_read_seek;
862 if (h->prot->url_read_seek)
863 (*s)->seekable |= AVIO_SEEKABLE_TIME;
865 (*s)->av_class = &ff_avio_class;
869 av_opt_free(internal);
872 return AVERROR(ENOMEM);
875 int ffio_set_buf_size(AVIOContext *s, int buf_size)
878 buffer = av_malloc(buf_size);
880 return AVERROR(ENOMEM);
884 s->buffer_size = buf_size;
886 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
890 static int url_resetbuf(AVIOContext *s, int flags)
892 assert(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
894 if (flags & AVIO_FLAG_WRITE) {
895 s->buf_end = s->buffer + s->buffer_size;
898 s->buf_end = s->buffer;
904 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
906 int64_t buffer_start;
908 int overlap, new_size, alloc_size;
911 return AVERROR(EINVAL);
913 buffer_size = s->buf_end - s->buffer;
915 /* the buffers must touch or overlap */
916 if ((buffer_start = s->pos - buffer_size) > buf_size)
917 return AVERROR(EINVAL);
919 overlap = buf_size - buffer_start;
920 new_size = buf_size + buffer_size - overlap;
922 alloc_size = FFMAX(s->buffer_size, new_size);
923 if (alloc_size > buf_size)
924 if (!(buf = av_realloc(buf, alloc_size)))
925 return AVERROR(ENOMEM);
927 if (new_size > buf_size) {
928 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
933 s->buf_ptr = s->buffer = buf;
934 s->buffer_size = alloc_size;
936 s->buf_end = s->buf_ptr + buf_size;
943 int avio_open(AVIOContext **s, const char *filename, int flags)
945 return avio_open2(s, filename, flags, NULL, NULL);
948 int avio_open2(AVIOContext **s, const char *filename, int flags,
949 const AVIOInterruptCB *int_cb, AVDictionary **options)
951 AVIOInternal *internal;
952 const URLProtocol **protocols;
953 char *proto_whitelist = NULL, *proto_blacklist = NULL;
954 AVDictionaryEntry *e;
959 e = av_dict_get(*options, "protocol_whitelist", NULL, 0);
961 proto_whitelist = e->value;
962 e = av_dict_get(*options, "protocol_blacklist", NULL, 0);
964 proto_blacklist = e->value;
967 protocols = ffurl_get_protocols(proto_whitelist, proto_blacklist);
969 return AVERROR(ENOMEM);
971 err = ffurl_open(&h, filename, flags, int_cb, options, protocols, NULL);
973 av_freep(&protocols);
977 err = ffio_fdopen(s, h);
980 av_freep(&protocols);
984 internal = (*s)->opaque;
985 internal->protocols = protocols;
988 err = av_opt_set_dict(internal, options);
998 int avio_close(AVIOContext *s)
1000 AVIOInternal *internal;
1007 internal = s->opaque;
1010 av_opt_free(internal);
1012 av_freep(&internal->protocols);
1013 av_freep(&s->opaque);
1014 av_freep(&s->buffer);
1016 avio_context_free(&s);
1018 return ffurl_close(h);
1021 int avio_closep(AVIOContext **s)
1023 int ret = avio_close(*s);
1028 int avio_printf(AVIOContext *s, const char *fmt, ...)
1035 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
1037 avio_write(s, buf, strlen(buf));
1041 int avio_pause(AVIOContext *s, int pause)
1044 return AVERROR(ENOSYS);
1045 return s->read_pause(s->opaque, pause);
1048 int64_t avio_seek_time(AVIOContext *s, int stream_index,
1049 int64_t timestamp, int flags)
1053 return AVERROR(ENOSYS);
1054 ret = s->read_seek(s->opaque, stream_index, timestamp, flags);
1057 s->buf_ptr = s->buf_end; // Flush buffer
1058 pos = s->seek(s->opaque, 0, SEEK_CUR);
1061 else if (pos != AVERROR(ENOSYS))
1067 /* output in a dynamic buffer */
1069 typedef struct DynBuffer {
1070 int pos, size, allocated_size;
1073 uint8_t io_buffer[1];
1076 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1078 DynBuffer *d = opaque;
1079 unsigned new_size, new_allocated_size;
1081 /* reallocate buffer if needed */
1082 new_size = d->pos + buf_size;
1083 new_allocated_size = d->allocated_size;
1084 if (new_size < d->pos || new_size > INT_MAX/2)
1086 while (new_size > new_allocated_size) {
1087 if (!new_allocated_size)
1088 new_allocated_size = new_size;
1090 new_allocated_size += new_allocated_size / 2 + 1;
1093 if (new_allocated_size > d->allocated_size) {
1095 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
1096 d->allocated_size = 0;
1100 d->allocated_size = new_allocated_size;
1102 memcpy(d->buffer + d->pos, buf, buf_size);
1104 if (d->pos > d->size)
1109 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1111 unsigned char buf1[4];
1114 /* packetized write: output the header */
1115 AV_WB32(buf1, buf_size);
1116 ret = dyn_buf_write(opaque, buf1, 4);
1121 return dyn_buf_write(opaque, buf, buf_size);
1124 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1126 DynBuffer *d = opaque;
1128 if (whence == SEEK_CUR)
1130 else if (whence == SEEK_END)
1132 if (offset < 0 || offset > 0x7fffffffLL)
1138 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1141 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1143 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1145 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1147 return AVERROR(ENOMEM);
1148 d->io_buffer_size = io_buffer_size;
1149 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1150 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1151 max_packet_size ? NULL : dyn_buf_seek);
1154 return AVERROR(ENOMEM);
1156 (*s)->max_packet_size = max_packet_size;
1160 int avio_open_dyn_buf(AVIOContext **s)
1162 return url_open_dyn_buf_internal(s, 0);
1165 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1167 if (max_packet_size <= 0)
1169 return url_open_dyn_buf_internal(s, max_packet_size);
1172 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1176 static const char padbuf[AV_INPUT_BUFFER_PADDING_SIZE] = {0};
1184 /* don't attempt to pad fixed-size packet buffers */
1185 if (!s->max_packet_size) {
1186 avio_write(s, padbuf, sizeof(padbuf));
1187 padding = AV_INPUT_BUFFER_PADDING_SIZE;
1193 *pbuffer = d->buffer;
1197 avio_context_free(&s);
1199 return size - padding;
1202 void ffio_free_dyn_buf(AVIOContext **s)
1207 avio_close_dyn_buf(*s, &tmp);
1212 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1214 DynBuffer *d = opaque;
1217 if (d->pos > d->size)
1222 int ffio_open_null_buf(AVIOContext **s)
1224 int ret = url_open_dyn_buf_internal(s, 0);
1226 AVIOContext *pb = *s;
1227 pb->write_packet = null_buf_write;
1232 int ffio_close_null_buf(AVIOContext *s)
1234 DynBuffer *d = s->opaque;
1242 avio_context_free(&s);