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/crc.h"
23 #include "libavutil/dict.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/log.h"
26 #include "libavutil/opt.h"
27 #include "libavutil/avassert.h"
30 #include "avio_internal.h"
35 #define IO_BUFFER_SIZE 32768
38 * Do seeks within this distance ahead of the current buffer by skipping
39 * data instead of calling the protocol seek function, for seekable
42 #define SHORT_SEEK_THRESHOLD 4096
44 static void *ffio_url_child_next(void *obj, void *prev)
47 return prev ? NULL : s->opaque;
50 static const AVClass *ffio_url_child_class_next(const AVClass *prev)
52 return prev ? NULL : &ffurl_context_class;
55 static const AVOption ffio_url_options[] = {
59 const AVClass ffio_url_class = {
60 .class_name = "AVIOContext",
61 .item_name = av_default_item_name,
62 .version = LIBAVUTIL_VERSION_INT,
63 .option = ffio_url_options,
64 .child_next = ffio_url_child_next,
65 .child_class_next = ffio_url_child_class_next,
68 static void fill_buffer(AVIOContext *s);
69 static int url_resetbuf(AVIOContext *s, int flags);
71 int ffio_init_context(AVIOContext *s,
72 unsigned char *buffer,
76 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
77 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
78 int64_t (*seek)(void *opaque, int64_t offset, int whence))
81 s->buffer_size = buffer_size;
86 url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
88 s->write_packet = write_packet;
89 s->read_packet = read_packet;
95 s->seekable = seek ? AVIO_SEEKABLE_NORMAL : 0;
96 s->max_packet_size = 0;
97 s->update_checksum = NULL;
99 if (!read_packet && !write_flag) {
100 s->pos = buffer_size;
101 s->buf_end = s->buffer + buffer_size;
103 s->read_pause = NULL;
109 AVIOContext *avio_alloc_context(
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))
118 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
121 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
122 read_packet, write_packet, seek);
126 static void writeout(AVIOContext *s, const uint8_t *data, int len)
128 if (s->write_packet && !s->error) {
129 int ret = s->write_packet(s->opaque, (uint8_t *)data, len);
134 s->writeout_count ++;
138 static void flush_buffer(AVIOContext *s)
140 if (s->buf_ptr > s->buffer) {
141 writeout(s, s->buffer, s->buf_ptr - s->buffer);
142 if (s->update_checksum) {
143 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
144 s->buf_ptr - s->checksum_ptr);
145 s->checksum_ptr = s->buffer;
148 s->buf_ptr = s->buffer;
151 void avio_w8(AVIOContext *s, int b)
153 av_assert2(b>=-128 && b<=255);
155 if (s->buf_ptr >= s->buf_end)
159 void ffio_fill(AVIOContext *s, int b, int count)
162 int len = FFMIN(s->buf_end - s->buf_ptr, count);
163 memset(s->buf_ptr, b, len);
166 if (s->buf_ptr >= s->buf_end)
173 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
175 if (s->direct && !s->update_checksum) {
177 writeout(s, buf, size);
181 int len = FFMIN(s->buf_end - s->buf_ptr, size);
182 memcpy(s->buf_ptr, buf, len);
185 if (s->buf_ptr >= s->buf_end)
193 void avio_flush(AVIOContext *s)
199 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
203 int force = whence & AVSEEK_FORCE;
204 whence &= ~AVSEEK_FORCE;
207 return AVERROR(EINVAL);
209 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
211 if (whence != SEEK_CUR && whence != SEEK_SET)
212 return AVERROR(EINVAL);
214 if (whence == SEEK_CUR) {
215 offset1 = pos + (s->buf_ptr - s->buffer);
220 offset1 = offset - pos;
221 if (!s->must_flush && (!s->direct || !s->seek) &&
222 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
223 /* can do the seek inside the buffer */
224 s->buf_ptr = s->buffer + offset1;
225 } else if ((!s->seekable ||
226 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
227 !s->write_flag && offset1 >= 0 &&
228 (!s->direct || !s->seek) &&
229 (whence != SEEK_END || force)) {
230 while(s->pos < offset && !s->eof_reached)
234 s->buf_ptr = s->buf_end + offset - s->pos;
243 return AVERROR(EPIPE);
244 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
248 s->buf_end = s->buffer;
249 s->buf_ptr = s->buffer;
256 int64_t avio_skip(AVIOContext *s, int64_t offset)
258 return avio_seek(s, offset, SEEK_CUR);
261 int64_t avio_size(AVIOContext *s)
266 return AVERROR(EINVAL);
269 return AVERROR(ENOSYS);
270 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
272 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
275 s->seek(s->opaque, s->pos, SEEK_SET);
280 int url_feof(AVIOContext *s)
288 return s->eof_reached;
291 void avio_wl32(AVIOContext *s, unsigned int val)
293 avio_w8(s, (uint8_t) val );
294 avio_w8(s, (uint8_t)(val >> 8 ));
295 avio_w8(s, (uint8_t)(val >> 16));
296 avio_w8(s, val >> 24 );
299 void avio_wb32(AVIOContext *s, unsigned int val)
301 avio_w8(s, val >> 24 );
302 avio_w8(s, (uint8_t)(val >> 16));
303 avio_w8(s, (uint8_t)(val >> 8 ));
304 avio_w8(s, (uint8_t) val );
307 int avio_put_str(AVIOContext *s, const char *str)
312 avio_write(s, (const unsigned char *) str, len);
318 int avio_put_str16le(AVIOContext *s, const char *str)
320 const uint8_t *q = str;
327 GET_UTF8(ch, *q++, break;)
328 PUT_UTF16(ch, tmp, avio_wl16(s, tmp); ret += 2;)
335 int ff_get_v_length(uint64_t val)
345 void ff_put_v(AVIOContext *bc, uint64_t val)
347 int i = ff_get_v_length(val);
350 avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
352 avio_w8(bc, val & 127);
355 void avio_wl64(AVIOContext *s, uint64_t val)
357 avio_wl32(s, (uint32_t)(val & 0xffffffff));
358 avio_wl32(s, (uint32_t)(val >> 32));
361 void avio_wb64(AVIOContext *s, uint64_t val)
363 avio_wb32(s, (uint32_t)(val >> 32));
364 avio_wb32(s, (uint32_t)(val & 0xffffffff));
367 void avio_wl16(AVIOContext *s, unsigned int val)
369 avio_w8(s, (uint8_t)val);
370 avio_w8(s, (int)val >> 8);
373 void avio_wb16(AVIOContext *s, unsigned int val)
375 avio_w8(s, (int)val >> 8);
376 avio_w8(s, (uint8_t)val);
379 void avio_wl24(AVIOContext *s, unsigned int val)
381 avio_wl16(s, val & 0xffff);
382 avio_w8(s, (int)val >> 16);
385 void avio_wb24(AVIOContext *s, unsigned int val)
387 avio_wb16(s, (int)val >> 8);
388 avio_w8(s, (uint8_t)val);
393 static void fill_buffer(AVIOContext *s)
395 int max_buffer_size = s->max_packet_size ?
396 s->max_packet_size : IO_BUFFER_SIZE;
397 uint8_t *dst = s->buf_end - s->buffer + max_buffer_size < s->buffer_size ?
398 s->buf_end : s->buffer;
399 int len = s->buffer_size - (dst - s->buffer);
401 /* can't fill the buffer without read_packet, just set EOF if appropriate */
402 if (!s->read_packet && s->buf_ptr >= s->buf_end)
405 /* no need to do anything if EOF already reached */
409 if (s->update_checksum && dst == s->buffer) {
410 if (s->buf_end > s->checksum_ptr)
411 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
412 s->buf_end - s->checksum_ptr);
413 s->checksum_ptr = s->buffer;
416 /* make buffer smaller in case it ended up large after probing */
417 if (s->read_packet && s->buffer_size > max_buffer_size) {
418 if (dst == s->buffer) {
419 ffio_set_buf_size(s, max_buffer_size);
421 s->checksum_ptr = dst = s->buffer;
423 av_assert0(len >= max_buffer_size);
424 len = max_buffer_size;
428 len = s->read_packet(s->opaque, dst, len);
432 /* do not modify buffer if EOF reached so that a seek back can
433 be done without rereading data */
440 s->buf_end = dst + len;
441 s->bytes_read += len;
445 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
448 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
451 unsigned long ffio_get_checksum(AVIOContext *s)
453 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
454 s->buf_ptr - s->checksum_ptr);
455 s->update_checksum = NULL;
459 void ffio_init_checksum(AVIOContext *s,
460 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
461 unsigned long checksum)
463 s->update_checksum = update_checksum;
464 if (s->update_checksum) {
465 s->checksum = checksum;
466 s->checksum_ptr = s->buf_ptr;
470 /* XXX: put an inline version */
471 int avio_r8(AVIOContext *s)
473 if (s->buf_ptr >= s->buf_end)
475 if (s->buf_ptr < s->buf_end)
476 return *s->buf_ptr++;
480 int avio_read(AVIOContext *s, unsigned char *buf, int size)
486 len = s->buf_end - s->buf_ptr;
489 if (len == 0 || s->write_flag) {
490 if((s->direct || size > s->buffer_size) && !s->update_checksum){
492 len = s->read_packet(s->opaque, buf, size);
494 /* do not modify buffer if EOF reached so that a seek back can
495 be done without rereading data */
502 s->bytes_read += len;
505 s->buf_ptr = s->buffer;
506 s->buf_end = s->buffer/* + len*/;
510 len = s->buf_end - s->buf_ptr;
515 memcpy(buf, s->buf_ptr, len);
522 if (s->error) return s->error;
523 if (url_feof(s)) return AVERROR_EOF;
528 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
530 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
536 return avio_read(s, buf, size);
540 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
547 if (s->read_packet && s->write_flag) {
548 len = s->read_packet(s->opaque, buf, size);
554 len = s->buf_end - s->buf_ptr;
556 /* Reset the buf_end pointer to the start of the buffer, to make sure
557 * the fill_buffer call tries to read as much data as fits into the
558 * full buffer, instead of just what space is left after buf_end.
559 * This avoids returning partial packets at the end of the buffer,
560 * for packet based inputs.
562 s->buf_end = s->buf_ptr = s->buffer;
564 len = s->buf_end - s->buf_ptr;
568 memcpy(buf, s->buf_ptr, len);
571 if (s->error) return s->error;
572 if (url_feof(s)) return AVERROR_EOF;
577 unsigned int avio_rl16(AVIOContext *s)
581 val |= avio_r8(s) << 8;
585 unsigned int avio_rl24(AVIOContext *s)
589 val |= avio_r8(s) << 16;
593 unsigned int avio_rl32(AVIOContext *s)
597 val |= avio_rl16(s) << 16;
601 uint64_t avio_rl64(AVIOContext *s)
604 val = (uint64_t)avio_rl32(s);
605 val |= (uint64_t)avio_rl32(s) << 32;
609 unsigned int avio_rb16(AVIOContext *s)
612 val = avio_r8(s) << 8;
617 unsigned int avio_rb24(AVIOContext *s)
620 val = avio_rb16(s) << 8;
624 unsigned int avio_rb32(AVIOContext *s)
627 val = avio_rb16(s) << 16;
632 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
639 if (c && i < maxlen-1)
641 } while (c != '\n' && c);
647 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
652 return AVERROR(EINVAL);
653 // reserve 1 byte for terminating 0
654 buflen = FFMIN(buflen - 1, maxlen);
655 for (i = 0; i < buflen; i++)
656 if (!(buf[i] = avio_r8(s)))
659 for (; i < maxlen; i++)
665 #define GET_STR16(type, read) \
666 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
671 return AVERROR(EINVAL); \
672 while (ret + 1 < maxlen) {\
675 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
678 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
684 GET_STR16(le, avio_rl16)
685 GET_STR16(be, avio_rb16)
689 uint64_t avio_rb64(AVIOContext *s)
692 val = (uint64_t)avio_rb32(s) << 32;
693 val |= (uint64_t)avio_rb32(s);
697 uint64_t ffio_read_varlen(AVIOContext *bc){
703 val= (val<<7) + (tmp&127);
708 int ffio_fdopen(AVIOContext **s, URLContext *h)
711 int buffer_size, max_packet_size;
713 max_packet_size = h->max_packet_size;
714 if (max_packet_size) {
715 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
717 buffer_size = IO_BUFFER_SIZE;
719 buffer = av_malloc(buffer_size);
721 return AVERROR(ENOMEM);
723 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
724 (void*)ffurl_read, (void*)ffurl_write, (void*)ffurl_seek);
727 return AVERROR(ENOMEM);
729 (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
730 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
731 (*s)->max_packet_size = max_packet_size;
733 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
734 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
736 (*s)->av_class = &ffio_url_class;
740 int ffio_ensure_seekback(AVIOContext *s, int buf_size)
743 int max_buffer_size = s->max_packet_size ?
744 s->max_packet_size : IO_BUFFER_SIZE;
746 buf_size += s->buf_ptr - s->buffer + max_buffer_size;
748 if (buf_size < s->buffer_size || s->seekable)
750 av_assert0(!s->write_flag);
752 buffer = av_malloc(buf_size);
754 return AVERROR(ENOMEM);
756 memcpy(buffer, s->buffer, s->buffer_size);
758 s->buf_ptr = buffer + (s->buf_ptr - s->buffer);
759 s->buf_end = buffer + (s->buf_end - s->buffer);
761 s->buffer_size = buf_size;
765 int ffio_set_buf_size(AVIOContext *s, int buf_size)
768 buffer = av_malloc(buf_size);
770 return AVERROR(ENOMEM);
774 s->buffer_size = buf_size;
776 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
780 static int url_resetbuf(AVIOContext *s, int flags)
782 av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
784 if (flags & AVIO_FLAG_WRITE) {
785 s->buf_end = s->buffer + s->buffer_size;
788 s->buf_end = s->buffer;
794 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
796 int64_t buffer_start;
798 int overlap, new_size, alloc_size;
799 uint8_t *buf = *bufp;
803 return AVERROR(EINVAL);
806 buffer_size = s->buf_end - s->buffer;
808 /* the buffers must touch or overlap */
809 if ((buffer_start = s->pos - buffer_size) > buf_size) {
811 return AVERROR(EINVAL);
814 overlap = buf_size - buffer_start;
815 new_size = buf_size + buffer_size - overlap;
817 alloc_size = FFMAX(s->buffer_size, new_size);
818 if (alloc_size > buf_size)
819 if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
820 return AVERROR(ENOMEM);
822 if (new_size > buf_size) {
823 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
828 s->buf_ptr = s->buffer = buf;
829 s->buffer_size = alloc_size;
831 s->buf_end = s->buf_ptr + buf_size;
838 int avio_open(AVIOContext **s, const char *filename, int flags)
840 return avio_open2(s, filename, flags, NULL, NULL);
843 int avio_open2(AVIOContext **s, const char *filename, int flags,
844 const AVIOInterruptCB *int_cb, AVDictionary **options)
849 err = ffurl_open(&h, filename, flags, int_cb, options);
852 err = ffio_fdopen(s, h);
860 int avio_close(AVIOContext *s)
869 av_freep(&s->buffer);
871 av_log(s, AV_LOG_DEBUG, "Statistics: %d seeks, %d writeouts\n", s->seek_count, s->writeout_count);
873 av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
875 return ffurl_close(h);
878 int avio_closep(AVIOContext **s)
880 int ret = avio_close(*s);
885 int avio_printf(AVIOContext *s, const char *fmt, ...)
892 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
894 avio_write(s, buf, strlen(buf));
898 int avio_pause(AVIOContext *s, int pause)
901 return AVERROR(ENOSYS);
902 return s->read_pause(s->opaque, pause);
905 int64_t avio_seek_time(AVIOContext *s, int stream_index,
906 int64_t timestamp, int flags)
908 URLContext *h = s->opaque;
911 return AVERROR(ENOSYS);
912 ret = s->read_seek(h, stream_index, timestamp, flags);
915 s->buf_ptr = s->buf_end; // Flush buffer
916 pos = s->seek(h, 0, SEEK_CUR);
919 else if (pos != AVERROR(ENOSYS))
925 /* output in a dynamic buffer */
927 typedef struct DynBuffer {
928 int pos, size, allocated_size;
931 uint8_t io_buffer[1];
934 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
936 DynBuffer *d = opaque;
937 unsigned new_size, new_allocated_size;
939 /* reallocate buffer if needed */
940 new_size = d->pos + buf_size;
941 new_allocated_size = d->allocated_size;
942 if (new_size < d->pos || new_size > INT_MAX/2)
944 while (new_size > new_allocated_size) {
945 if (!new_allocated_size)
946 new_allocated_size = new_size;
948 new_allocated_size += new_allocated_size / 2 + 1;
951 if (new_allocated_size > d->allocated_size) {
953 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
954 d->allocated_size = 0;
958 d->allocated_size = new_allocated_size;
960 memcpy(d->buffer + d->pos, buf, buf_size);
962 if (d->pos > d->size)
967 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
969 unsigned char buf1[4];
972 /* packetized write: output the header */
973 AV_WB32(buf1, buf_size);
974 ret = dyn_buf_write(opaque, buf1, 4);
979 return dyn_buf_write(opaque, buf, buf_size);
982 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
984 DynBuffer *d = opaque;
986 if (whence == SEEK_CUR)
988 else if (whence == SEEK_END)
990 if (offset < 0 || offset > 0x7fffffffLL)
996 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
999 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1001 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1003 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1005 return AVERROR(ENOMEM);
1006 d->io_buffer_size = io_buffer_size;
1007 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1008 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1009 max_packet_size ? NULL : dyn_buf_seek);
1012 return AVERROR(ENOMEM);
1014 (*s)->max_packet_size = max_packet_size;
1018 int avio_open_dyn_buf(AVIOContext **s)
1020 return url_open_dyn_buf_internal(s, 0);
1023 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1025 if (max_packet_size <= 0)
1027 return url_open_dyn_buf_internal(s, max_packet_size);
1030 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1032 DynBuffer *d = s->opaque;
1034 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1037 /* don't attempt to pad fixed-size packet buffers */
1038 if (!s->max_packet_size) {
1039 avio_write(s, padbuf, sizeof(padbuf));
1040 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1045 *pbuffer = d->buffer;
1049 return size - padding;
1052 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1054 DynBuffer *d = opaque;
1057 if (d->pos > d->size)
1062 int ffio_open_null_buf(AVIOContext **s)
1064 int ret = url_open_dyn_buf_internal(s, 0);
1066 AVIOContext *pb = *s;
1067 pb->write_packet = null_buf_write;
1072 int ffio_close_null_buf(AVIOContext *s)
1074 DynBuffer *d = s->opaque;