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;
100 s->short_seek_threshold = SHORT_SEEK_THRESHOLD;
102 if (!read_packet && !write_flag) {
103 s->pos = buffer_size;
104 s->buf_end = s->buffer + buffer_size;
106 s->read_pause = NULL;
112 AVIOContext *avio_alloc_context(
113 unsigned char *buffer,
117 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
118 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
119 int64_t (*seek)(void *opaque, int64_t offset, int whence))
121 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
124 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
125 read_packet, write_packet, seek);
129 static void writeout(AVIOContext *s, const uint8_t *data, int len)
131 if (s->write_packet && !s->error) {
132 int ret = s->write_packet(s->opaque, (uint8_t *)data, len);
137 s->writeout_count ++;
141 static void flush_buffer(AVIOContext *s)
143 if (s->write_flag && s->buf_ptr > s->buffer) {
144 writeout(s, s->buffer, s->buf_ptr - s->buffer);
145 if (s->update_checksum) {
146 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
147 s->buf_ptr - s->checksum_ptr);
148 s->checksum_ptr = s->buffer;
151 s->buf_ptr = s->buffer;
153 s->buf_end = s->buffer;
156 void avio_w8(AVIOContext *s, int b)
158 av_assert2(b>=-128 && b<=255);
160 if (s->buf_ptr >= s->buf_end)
164 void ffio_fill(AVIOContext *s, int b, int count)
167 int len = FFMIN(s->buf_end - s->buf_ptr, count);
168 memset(s->buf_ptr, b, len);
171 if (s->buf_ptr >= s->buf_end)
178 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
180 if (s->direct && !s->update_checksum) {
182 writeout(s, buf, size);
186 int len = FFMIN(s->buf_end - s->buf_ptr, size);
187 memcpy(s->buf_ptr, buf, len);
190 if (s->buf_ptr >= s->buf_end)
198 void avio_flush(AVIOContext *s)
204 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
208 int force = whence & AVSEEK_FORCE;
210 whence &= ~AVSEEK_FORCE;
213 return AVERROR(EINVAL);
215 buffer_size = s->buf_end - s->buffer;
216 // pos is the absolute position that the beginning of s->buffer corresponds to in the file
217 pos = s->pos - (s->write_flag ? 0 : buffer_size);
219 if (whence != SEEK_CUR && whence != SEEK_SET)
220 return AVERROR(EINVAL);
222 if (whence == SEEK_CUR) {
223 offset1 = pos + (s->buf_ptr - s->buffer);
229 return AVERROR(EINVAL);
231 offset1 = offset - pos; // "offset1" is the relative offset from the beginning of s->buffer
232 if (!s->must_flush && (!s->direct || !s->seek) &&
233 offset1 >= 0 && offset1 <= buffer_size - s->write_flag) {
234 /* can do the seek inside the buffer */
235 s->buf_ptr = s->buffer + offset1;
236 } else if ((!s->seekable ||
237 offset1 <= buffer_size + s->short_seek_threshold) &&
238 !s->write_flag && offset1 >= 0 &&
239 (!s->direct || !s->seek) &&
240 (whence != SEEK_END || force)) {
241 while(s->pos < offset && !s->eof_reached)
245 s->buf_ptr = s->buf_end - (s->pos - offset);
246 } else if(!s->write_flag && offset1 < 0 && -offset1 < buffer_size>>1 && s->seek && offset > 0) {
249 pos -= FFMIN(buffer_size>>1, pos);
250 if ((res = s->seek(s->opaque, pos, SEEK_SET)) < 0)
253 s->buf_ptr = s->buffer;
257 return avio_seek(s, offset, SEEK_SET | force);
265 return AVERROR(EPIPE);
266 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
270 s->buf_end = s->buffer;
271 s->buf_ptr = s->buffer;
278 int64_t avio_skip(AVIOContext *s, int64_t offset)
280 return avio_seek(s, offset, SEEK_CUR);
283 int64_t avio_size(AVIOContext *s)
288 return AVERROR(EINVAL);
291 return AVERROR(ENOSYS);
292 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
294 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
297 s->seek(s->opaque, s->pos, SEEK_SET);
302 int avio_feof(AVIOContext *s)
310 return s->eof_reached;
314 int url_feof(AVIOContext *s)
320 void avio_wl32(AVIOContext *s, unsigned int val)
322 avio_w8(s, (uint8_t) val );
323 avio_w8(s, (uint8_t)(val >> 8 ));
324 avio_w8(s, (uint8_t)(val >> 16));
325 avio_w8(s, val >> 24 );
328 void avio_wb32(AVIOContext *s, unsigned int val)
330 avio_w8(s, val >> 24 );
331 avio_w8(s, (uint8_t)(val >> 16));
332 avio_w8(s, (uint8_t)(val >> 8 ));
333 avio_w8(s, (uint8_t) val );
336 int avio_put_str(AVIOContext *s, const char *str)
341 avio_write(s, (const unsigned char *) str, len);
347 static inline int put_str16(AVIOContext *s, const char *str, const int be)
349 const uint8_t *q = str;
357 GET_UTF8(ch, *q++, goto invalid;)
358 PUT_UTF16(ch, tmp, be ? avio_wb16(s, tmp) : avio_wl16(s, tmp);
362 av_log(s, AV_LOG_ERROR, "Invaid UTF8 sequence in avio_put_str16%s\n", be ? "be" : "le");
363 err = AVERROR(EINVAL);
377 #define PUT_STR16(type, big_endian) \
378 int avio_put_str16 ## type(AVIOContext *s, const char *str) \
380 return put_str16(s, str, big_endian); \
388 int ff_get_v_length(uint64_t val)
398 void ff_put_v(AVIOContext *bc, uint64_t val)
400 int i = ff_get_v_length(val);
403 avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
405 avio_w8(bc, val & 127);
408 void avio_wl64(AVIOContext *s, uint64_t val)
410 avio_wl32(s, (uint32_t)(val & 0xffffffff));
411 avio_wl32(s, (uint32_t)(val >> 32));
414 void avio_wb64(AVIOContext *s, uint64_t val)
416 avio_wb32(s, (uint32_t)(val >> 32));
417 avio_wb32(s, (uint32_t)(val & 0xffffffff));
420 void avio_wl16(AVIOContext *s, unsigned int val)
422 avio_w8(s, (uint8_t)val);
423 avio_w8(s, (int)val >> 8);
426 void avio_wb16(AVIOContext *s, unsigned int val)
428 avio_w8(s, (int)val >> 8);
429 avio_w8(s, (uint8_t)val);
432 void avio_wl24(AVIOContext *s, unsigned int val)
434 avio_wl16(s, val & 0xffff);
435 avio_w8(s, (int)val >> 16);
438 void avio_wb24(AVIOContext *s, unsigned int val)
440 avio_wb16(s, (int)val >> 8);
441 avio_w8(s, (uint8_t)val);
446 static void fill_buffer(AVIOContext *s)
448 int max_buffer_size = s->max_packet_size ?
449 s->max_packet_size : IO_BUFFER_SIZE;
450 uint8_t *dst = s->buf_end - s->buffer + max_buffer_size < s->buffer_size ?
451 s->buf_end : s->buffer;
452 int len = s->buffer_size - (dst - s->buffer);
454 /* can't fill the buffer without read_packet, just set EOF if appropriate */
455 if (!s->read_packet && s->buf_ptr >= s->buf_end)
458 /* no need to do anything if EOF already reached */
462 if (s->update_checksum && dst == s->buffer) {
463 if (s->buf_end > s->checksum_ptr)
464 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
465 s->buf_end - s->checksum_ptr);
466 s->checksum_ptr = s->buffer;
469 /* make buffer smaller in case it ended up large after probing */
470 if (s->read_packet && s->orig_buffer_size && s->buffer_size > s->orig_buffer_size) {
471 if (dst == s->buffer) {
472 int ret = ffio_set_buf_size(s, s->orig_buffer_size);
474 av_log(s, AV_LOG_WARNING, "Failed to decrease buffer size\n");
476 s->checksum_ptr = dst = s->buffer;
478 av_assert0(len >= s->orig_buffer_size);
479 len = s->orig_buffer_size;
483 len = s->read_packet(s->opaque, dst, len);
487 /* do not modify buffer if EOF reached so that a seek back can
488 be done without rereading data */
495 s->buf_end = dst + len;
496 s->bytes_read += len;
500 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
503 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
506 unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf,
509 return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len);
512 unsigned long ffio_get_checksum(AVIOContext *s)
514 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
515 s->buf_ptr - s->checksum_ptr);
516 s->update_checksum = NULL;
520 void ffio_init_checksum(AVIOContext *s,
521 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
522 unsigned long checksum)
524 s->update_checksum = update_checksum;
525 if (s->update_checksum) {
526 s->checksum = checksum;
527 s->checksum_ptr = s->buf_ptr;
531 /* XXX: put an inline version */
532 int avio_r8(AVIOContext *s)
534 if (s->buf_ptr >= s->buf_end)
536 if (s->buf_ptr < s->buf_end)
537 return *s->buf_ptr++;
541 int avio_read(AVIOContext *s, unsigned char *buf, int size)
547 len = FFMIN(s->buf_end - s->buf_ptr, size);
548 if (len == 0 || s->write_flag) {
549 if((s->direct || size > s->buffer_size) && !s->update_checksum) {
550 // bypass the buffer and read data directly into buf
552 len = s->read_packet(s->opaque, buf, size);
555 /* do not modify buffer if EOF reached so that a seek back can
556 be done without rereading data */
563 s->bytes_read += len;
567 s->buf_ptr = s->buffer;
568 s->buf_end = s->buffer/* + len*/;
572 len = s->buf_end - s->buf_ptr;
577 memcpy(buf, s->buf_ptr, len);
584 if (s->error) return s->error;
585 if (avio_feof(s)) return AVERROR_EOF;
590 int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
592 int ret = avio_read(s, buf, size);
594 return AVERROR_INVALIDDATA;
598 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
600 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
606 return avio_read(s, buf, size);
610 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
617 if (s->read_packet && s->write_flag) {
618 len = s->read_packet(s->opaque, buf, size);
624 len = s->buf_end - s->buf_ptr;
626 /* Reset the buf_end pointer to the start of the buffer, to make sure
627 * the fill_buffer call tries to read as much data as fits into the
628 * full buffer, instead of just what space is left after buf_end.
629 * This avoids returning partial packets at the end of the buffer,
630 * for packet based inputs.
632 s->buf_end = s->buf_ptr = s->buffer;
634 len = s->buf_end - s->buf_ptr;
638 memcpy(buf, s->buf_ptr, len);
641 if (s->error) return s->error;
642 if (avio_feof(s)) return AVERROR_EOF;
647 unsigned int avio_rl16(AVIOContext *s)
651 val |= avio_r8(s) << 8;
655 unsigned int avio_rl24(AVIOContext *s)
659 val |= avio_r8(s) << 16;
663 unsigned int avio_rl32(AVIOContext *s)
667 val |= avio_rl16(s) << 16;
671 uint64_t avio_rl64(AVIOContext *s)
674 val = (uint64_t)avio_rl32(s);
675 val |= (uint64_t)avio_rl32(s) << 32;
679 unsigned int avio_rb16(AVIOContext *s)
682 val = avio_r8(s) << 8;
687 unsigned int avio_rb24(AVIOContext *s)
690 val = avio_rb16(s) << 8;
694 unsigned int avio_rb32(AVIOContext *s)
697 val = avio_rb16(s) << 16;
702 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
709 if (c && i < maxlen-1)
711 } while (c != '\n' && c != '\r' && c);
712 if (c == '\r' && avio_r8(s) != '\n' && !avio_feof(s))
719 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
724 return AVERROR(EINVAL);
725 // reserve 1 byte for terminating 0
726 buflen = FFMIN(buflen - 1, maxlen);
727 for (i = 0; i < buflen; i++)
728 if (!(buf[i] = avio_r8(s)))
731 for (; i < maxlen; i++)
737 #define GET_STR16(type, read) \
738 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
743 return AVERROR(EINVAL); \
744 while (ret + 1 < maxlen) {\
747 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
750 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
756 GET_STR16(le, avio_rl16)
757 GET_STR16(be, avio_rb16)
761 uint64_t avio_rb64(AVIOContext *s)
764 val = (uint64_t)avio_rb32(s) << 32;
765 val |= (uint64_t)avio_rb32(s);
769 uint64_t ffio_read_varlen(AVIOContext *bc){
775 val= (val<<7) + (tmp&127);
780 int ffio_fdopen(AVIOContext **s, URLContext *h)
783 int buffer_size, max_packet_size;
785 max_packet_size = h->max_packet_size;
786 if (max_packet_size) {
787 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
789 buffer_size = IO_BUFFER_SIZE;
791 buffer = av_malloc(buffer_size);
793 return AVERROR(ENOMEM);
795 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
796 (int (*)(void *, uint8_t *, int)) ffurl_read,
797 (int (*)(void *, uint8_t *, int)) ffurl_write,
798 (int64_t (*)(void *, int64_t, int)) ffurl_seek);
801 return AVERROR(ENOMEM);
803 (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
804 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
805 (*s)->max_packet_size = max_packet_size;
807 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
808 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
810 (*s)->av_class = &ff_avio_class;
814 int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
817 int max_buffer_size = s->max_packet_size ?
818 s->max_packet_size : IO_BUFFER_SIZE;
819 int filled = s->buf_end - s->buffer;
820 ptrdiff_t checksum_ptr_offset = s->checksum_ptr ? s->checksum_ptr - s->buffer : -1;
822 buf_size += s->buf_ptr - s->buffer + max_buffer_size;
824 if (buf_size < filled || s->seekable || !s->read_packet)
826 av_assert0(!s->write_flag);
828 buffer = av_malloc(buf_size);
830 return AVERROR(ENOMEM);
832 memcpy(buffer, s->buffer, filled);
834 s->buf_ptr = buffer + (s->buf_ptr - s->buffer);
835 s->buf_end = buffer + (s->buf_end - s->buffer);
837 s->buffer_size = buf_size;
838 if (checksum_ptr_offset >= 0)
839 s->checksum_ptr = s->buffer + checksum_ptr_offset;
843 int ffio_set_buf_size(AVIOContext *s, int buf_size)
846 buffer = av_malloc(buf_size);
848 return AVERROR(ENOMEM);
852 s->orig_buffer_size =
853 s->buffer_size = buf_size;
855 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
859 static int url_resetbuf(AVIOContext *s, int flags)
861 av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
863 if (flags & AVIO_FLAG_WRITE) {
864 s->buf_end = s->buffer + s->buffer_size;
867 s->buf_end = s->buffer;
873 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
875 int64_t buffer_start;
877 int overlap, new_size, alloc_size;
878 uint8_t *buf = *bufp;
882 return AVERROR(EINVAL);
885 buffer_size = s->buf_end - s->buffer;
887 /* the buffers must touch or overlap */
888 if ((buffer_start = s->pos - buffer_size) > buf_size) {
890 return AVERROR(EINVAL);
893 overlap = buf_size - buffer_start;
894 new_size = buf_size + buffer_size - overlap;
896 alloc_size = FFMAX(s->buffer_size, new_size);
897 if (alloc_size > buf_size)
898 if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
899 return AVERROR(ENOMEM);
901 if (new_size > buf_size) {
902 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
907 s->buf_ptr = s->buffer = buf;
908 s->buffer_size = alloc_size;
910 s->buf_end = s->buf_ptr + buf_size;
917 int avio_open(AVIOContext **s, const char *filename, int flags)
919 return avio_open2(s, filename, flags, NULL, NULL);
922 int avio_open2(AVIOContext **s, const char *filename, int flags,
923 const AVIOInterruptCB *int_cb, AVDictionary **options)
928 err = ffurl_open(&h, filename, flags, int_cb, options);
931 err = ffio_fdopen(s, h);
939 int ffio_open2_wrapper(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
940 const AVIOInterruptCB *int_cb, AVDictionary **options)
942 return avio_open2(pb, url, flags, int_cb, options);
945 int avio_close(AVIOContext *s)
954 av_freep(&s->buffer);
956 av_log(s, AV_LOG_DEBUG, "Statistics: %d seeks, %d writeouts\n", s->seek_count, s->writeout_count);
958 av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
960 return ffurl_close(h);
963 int avio_closep(AVIOContext **s)
965 int ret = avio_close(*s);
970 int avio_printf(AVIOContext *s, const char *fmt, ...)
973 char buf[4096]; /* update doc entry in avio.h if changed */
977 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
979 avio_write(s, buf, strlen(buf));
983 int avio_pause(AVIOContext *s, int pause)
986 return AVERROR(ENOSYS);
987 return s->read_pause(s->opaque, pause);
990 int64_t avio_seek_time(AVIOContext *s, int stream_index,
991 int64_t timestamp, int flags)
993 URLContext *h = s->opaque;
996 return AVERROR(ENOSYS);
997 ret = s->read_seek(h, stream_index, timestamp, flags);
1000 s->buf_ptr = s->buf_end; // Flush buffer
1001 pos = s->seek(h, 0, SEEK_CUR);
1004 else if (pos != AVERROR(ENOSYS))
1010 int avio_read_to_bprint(AVIOContext *h, AVBPrint *pb, size_t max_size)
1015 ret = avio_read(h, buf, FFMIN(max_size, sizeof(buf)));
1016 if (ret == AVERROR_EOF)
1020 av_bprint_append_data(pb, buf, ret);
1021 if (!av_bprint_is_complete(pb))
1022 return AVERROR(ENOMEM);
1028 int avio_accept(AVIOContext *s, AVIOContext **c)
1031 URLContext *sc = s->opaque;
1032 URLContext *cc = NULL;
1033 ret = ffurl_accept(sc, &cc);
1036 return ffio_fdopen(c, cc);
1039 int avio_handshake(AVIOContext *c)
1041 URLContext *cc = c->opaque;
1042 return ffurl_handshake(cc);
1045 /* output in a dynamic buffer */
1047 typedef struct DynBuffer {
1048 int pos, size, allocated_size;
1051 uint8_t io_buffer[1];
1054 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1056 DynBuffer *d = opaque;
1057 unsigned new_size, new_allocated_size;
1059 /* reallocate buffer if needed */
1060 new_size = d->pos + buf_size;
1061 new_allocated_size = d->allocated_size;
1062 if (new_size < d->pos || new_size > INT_MAX/2)
1064 while (new_size > new_allocated_size) {
1065 if (!new_allocated_size)
1066 new_allocated_size = new_size;
1068 new_allocated_size += new_allocated_size / 2 + 1;
1071 if (new_allocated_size > d->allocated_size) {
1073 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
1074 d->allocated_size = 0;
1078 d->allocated_size = new_allocated_size;
1080 memcpy(d->buffer + d->pos, buf, buf_size);
1082 if (d->pos > d->size)
1087 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1089 unsigned char buf1[4];
1092 /* packetized write: output the header */
1093 AV_WB32(buf1, buf_size);
1094 ret = dyn_buf_write(opaque, buf1, 4);
1099 return dyn_buf_write(opaque, buf, buf_size);
1102 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1104 DynBuffer *d = opaque;
1106 if (whence == SEEK_CUR)
1108 else if (whence == SEEK_END)
1110 if (offset < 0 || offset > 0x7fffffffLL)
1116 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1119 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1121 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1123 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1125 return AVERROR(ENOMEM);
1126 d->io_buffer_size = io_buffer_size;
1127 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1128 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1129 max_packet_size ? NULL : dyn_buf_seek);
1132 return AVERROR(ENOMEM);
1134 (*s)->max_packet_size = max_packet_size;
1138 int avio_open_dyn_buf(AVIOContext **s)
1140 return url_open_dyn_buf_internal(s, 0);
1143 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1145 if (max_packet_size <= 0)
1147 return url_open_dyn_buf_internal(s, max_packet_size);
1150 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1154 static const char padbuf[AV_INPUT_BUFFER_PADDING_SIZE] = {0};
1162 /* don't attempt to pad fixed-size packet buffers */
1163 if (!s->max_packet_size) {
1164 avio_write(s, padbuf, sizeof(padbuf));
1165 padding = AV_INPUT_BUFFER_PADDING_SIZE;
1171 *pbuffer = d->buffer;
1175 return size - padding;
1178 void ffio_free_dyn_buf(AVIOContext **s)
1183 avio_close_dyn_buf(*s, &tmp);
1188 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1190 DynBuffer *d = opaque;
1193 if (d->pos > d->size)
1198 int ffio_open_null_buf(AVIOContext **s)
1200 int ret = url_open_dyn_buf_internal(s, 0);
1202 AVIOContext *pb = *s;
1203 pb->write_packet = null_buf_write;
1208 int ffio_close_null_buf(AVIOContext *s)
1210 DynBuffer *d = s->opaque;