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;
205 whence &= ~AVSEEK_FORCE;
208 return AVERROR(EINVAL);
210 buffer_size = s->buf_end - s->buffer;
211 pos = s->pos - (s->write_flag ? 0 : buffer_size);
213 if (whence != SEEK_CUR && whence != SEEK_SET)
214 return AVERROR(EINVAL);
216 if (whence == SEEK_CUR) {
217 offset1 = pos + (s->buf_ptr - s->buffer);
222 offset1 = offset - pos;
223 if (!s->must_flush && (!s->direct || !s->seek) &&
224 offset1 >= 0 && offset1 <= buffer_size) {
225 /* can do the seek inside the buffer */
226 s->buf_ptr = s->buffer + offset1;
227 } else if ((!s->seekable ||
228 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
229 !s->write_flag && offset1 >= 0 &&
230 (!s->direct || !s->seek) &&
231 (whence != SEEK_END || force)) {
232 while(s->pos < offset && !s->eof_reached)
236 s->buf_ptr = s->buf_end + offset - s->pos;
237 } else if(!s->write_flag && offset1 < 0 && -offset1 < buffer_size>>1 && s->seek && offset > 0) {
240 pos -= FFMIN(buffer_size>>1, pos);
241 if ((res = s->seek(s->opaque, pos, SEEK_SET)) < 0)
244 s->buf_ptr = s->buffer;
248 return avio_seek(s, offset, SEEK_SET | force);
256 return AVERROR(EPIPE);
257 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
261 s->buf_end = s->buffer;
262 s->buf_ptr = s->buffer;
269 int64_t avio_skip(AVIOContext *s, int64_t offset)
271 return avio_seek(s, offset, SEEK_CUR);
274 int64_t avio_size(AVIOContext *s)
279 return AVERROR(EINVAL);
282 return AVERROR(ENOSYS);
283 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
285 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
288 s->seek(s->opaque, s->pos, SEEK_SET);
293 int url_feof(AVIOContext *s)
301 return s->eof_reached;
304 void avio_wl32(AVIOContext *s, unsigned int val)
306 avio_w8(s, (uint8_t) val );
307 avio_w8(s, (uint8_t)(val >> 8 ));
308 avio_w8(s, (uint8_t)(val >> 16));
309 avio_w8(s, val >> 24 );
312 void avio_wb32(AVIOContext *s, unsigned int val)
314 avio_w8(s, val >> 24 );
315 avio_w8(s, (uint8_t)(val >> 16));
316 avio_w8(s, (uint8_t)(val >> 8 ));
317 avio_w8(s, (uint8_t) val );
320 int avio_put_str(AVIOContext *s, const char *str)
325 avio_write(s, (const unsigned char *) str, len);
331 int avio_put_str16le(AVIOContext *s, const char *str)
333 const uint8_t *q = str;
341 GET_UTF8(ch, *q++, goto invalid;)
342 PUT_UTF16(ch, tmp, avio_wl16(s, tmp); ret += 2;)
345 av_log(s, AV_LOG_ERROR, "Invaid UTF8 sequence in avio_put_str16le\n");
346 err = AVERROR(EINVAL);
355 int ff_get_v_length(uint64_t val)
365 void ff_put_v(AVIOContext *bc, uint64_t val)
367 int i = ff_get_v_length(val);
370 avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
372 avio_w8(bc, val & 127);
375 void avio_wl64(AVIOContext *s, uint64_t val)
377 avio_wl32(s, (uint32_t)(val & 0xffffffff));
378 avio_wl32(s, (uint32_t)(val >> 32));
381 void avio_wb64(AVIOContext *s, uint64_t val)
383 avio_wb32(s, (uint32_t)(val >> 32));
384 avio_wb32(s, (uint32_t)(val & 0xffffffff));
387 void avio_wl16(AVIOContext *s, unsigned int val)
389 avio_w8(s, (uint8_t)val);
390 avio_w8(s, (int)val >> 8);
393 void avio_wb16(AVIOContext *s, unsigned int val)
395 avio_w8(s, (int)val >> 8);
396 avio_w8(s, (uint8_t)val);
399 void avio_wl24(AVIOContext *s, unsigned int val)
401 avio_wl16(s, val & 0xffff);
402 avio_w8(s, (int)val >> 16);
405 void avio_wb24(AVIOContext *s, unsigned int val)
407 avio_wb16(s, (int)val >> 8);
408 avio_w8(s, (uint8_t)val);
413 static void fill_buffer(AVIOContext *s)
415 int max_buffer_size = s->max_packet_size ?
416 s->max_packet_size : IO_BUFFER_SIZE;
417 uint8_t *dst = s->buf_end - s->buffer + max_buffer_size < s->buffer_size ?
418 s->buf_end : s->buffer;
419 int len = s->buffer_size - (dst - s->buffer);
421 /* can't fill the buffer without read_packet, just set EOF if appropriate */
422 if (!s->read_packet && s->buf_ptr >= s->buf_end)
425 /* no need to do anything if EOF already reached */
429 if (s->update_checksum && dst == s->buffer) {
430 if (s->buf_end > s->checksum_ptr)
431 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
432 s->buf_end - s->checksum_ptr);
433 s->checksum_ptr = s->buffer;
436 /* make buffer smaller in case it ended up large after probing */
437 if (s->read_packet && s->buffer_size > max_buffer_size) {
438 if (dst == s->buffer) {
439 ffio_set_buf_size(s, max_buffer_size);
441 s->checksum_ptr = dst = s->buffer;
443 av_assert0(len >= max_buffer_size);
444 len = max_buffer_size;
448 len = s->read_packet(s->opaque, dst, len);
452 /* do not modify buffer if EOF reached so that a seek back can
453 be done without rereading data */
460 s->buf_end = dst + len;
461 s->bytes_read += len;
465 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
468 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
471 unsigned long ffio_get_checksum(AVIOContext *s)
473 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
474 s->buf_ptr - s->checksum_ptr);
475 s->update_checksum = NULL;
479 void ffio_init_checksum(AVIOContext *s,
480 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
481 unsigned long checksum)
483 s->update_checksum = update_checksum;
484 if (s->update_checksum) {
485 s->checksum = checksum;
486 s->checksum_ptr = s->buf_ptr;
490 /* XXX: put an inline version */
491 int avio_r8(AVIOContext *s)
493 if (s->buf_ptr >= s->buf_end)
495 if (s->buf_ptr < s->buf_end)
496 return *s->buf_ptr++;
500 int avio_read(AVIOContext *s, unsigned char *buf, int size)
506 len = s->buf_end - s->buf_ptr;
509 if (len == 0 || s->write_flag) {
510 if((s->direct || size > s->buffer_size) && !s->update_checksum){
512 len = s->read_packet(s->opaque, buf, size);
514 /* do not modify buffer if EOF reached so that a seek back can
515 be done without rereading data */
522 s->bytes_read += len;
525 s->buf_ptr = s->buffer;
526 s->buf_end = s->buffer/* + len*/;
530 len = s->buf_end - s->buf_ptr;
535 memcpy(buf, s->buf_ptr, len);
542 if (s->error) return s->error;
543 if (url_feof(s)) return AVERROR_EOF;
548 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
550 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
556 return avio_read(s, buf, size);
560 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
567 if (s->read_packet && s->write_flag) {
568 len = s->read_packet(s->opaque, buf, size);
574 len = s->buf_end - s->buf_ptr;
576 /* Reset the buf_end pointer to the start of the buffer, to make sure
577 * the fill_buffer call tries to read as much data as fits into the
578 * full buffer, instead of just what space is left after buf_end.
579 * This avoids returning partial packets at the end of the buffer,
580 * for packet based inputs.
582 s->buf_end = s->buf_ptr = s->buffer;
584 len = s->buf_end - s->buf_ptr;
588 memcpy(buf, s->buf_ptr, len);
591 if (s->error) return s->error;
592 if (url_feof(s)) return AVERROR_EOF;
597 unsigned int avio_rl16(AVIOContext *s)
601 val |= avio_r8(s) << 8;
605 unsigned int avio_rl24(AVIOContext *s)
609 val |= avio_r8(s) << 16;
613 unsigned int avio_rl32(AVIOContext *s)
617 val |= avio_rl16(s) << 16;
621 uint64_t avio_rl64(AVIOContext *s)
624 val = (uint64_t)avio_rl32(s);
625 val |= (uint64_t)avio_rl32(s) << 32;
629 unsigned int avio_rb16(AVIOContext *s)
632 val = avio_r8(s) << 8;
637 unsigned int avio_rb24(AVIOContext *s)
640 val = avio_rb16(s) << 8;
644 unsigned int avio_rb32(AVIOContext *s)
647 val = avio_rb16(s) << 16;
652 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
659 if (c && i < maxlen-1)
661 } while (c != '\n' && c);
667 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
672 return AVERROR(EINVAL);
673 // reserve 1 byte for terminating 0
674 buflen = FFMIN(buflen - 1, maxlen);
675 for (i = 0; i < buflen; i++)
676 if (!(buf[i] = avio_r8(s)))
679 for (; i < maxlen; i++)
685 #define GET_STR16(type, read) \
686 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
691 return AVERROR(EINVAL); \
692 while (ret + 1 < maxlen) {\
695 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
698 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
704 GET_STR16(le, avio_rl16)
705 GET_STR16(be, avio_rb16)
709 uint64_t avio_rb64(AVIOContext *s)
712 val = (uint64_t)avio_rb32(s) << 32;
713 val |= (uint64_t)avio_rb32(s);
717 uint64_t ffio_read_varlen(AVIOContext *bc){
723 val= (val<<7) + (tmp&127);
728 int ffio_fdopen(AVIOContext **s, URLContext *h)
731 int buffer_size, max_packet_size;
733 max_packet_size = h->max_packet_size;
734 if (max_packet_size) {
735 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
737 buffer_size = IO_BUFFER_SIZE;
739 buffer = av_malloc(buffer_size);
741 return AVERROR(ENOMEM);
743 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
744 (void*)ffurl_read, (void*)ffurl_write, (void*)ffurl_seek);
747 return AVERROR(ENOMEM);
749 (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
750 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
751 (*s)->max_packet_size = max_packet_size;
753 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
754 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
756 (*s)->av_class = &ffio_url_class;
760 int ffio_ensure_seekback(AVIOContext *s, int buf_size)
763 int max_buffer_size = s->max_packet_size ?
764 s->max_packet_size : IO_BUFFER_SIZE;
766 buf_size += s->buf_ptr - s->buffer + max_buffer_size;
768 if (buf_size < s->buffer_size || s->seekable)
770 av_assert0(!s->write_flag);
772 buffer = av_malloc(buf_size);
774 return AVERROR(ENOMEM);
776 memcpy(buffer, s->buffer, s->buffer_size);
778 s->buf_ptr = buffer + (s->buf_ptr - s->buffer);
779 s->buf_end = buffer + (s->buf_end - s->buffer);
781 s->buffer_size = buf_size;
785 int ffio_set_buf_size(AVIOContext *s, int buf_size)
788 buffer = av_malloc(buf_size);
790 return AVERROR(ENOMEM);
794 s->buffer_size = buf_size;
796 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
800 static int url_resetbuf(AVIOContext *s, int flags)
802 av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
804 if (flags & AVIO_FLAG_WRITE) {
805 s->buf_end = s->buffer + s->buffer_size;
808 s->buf_end = s->buffer;
814 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
816 int64_t buffer_start;
818 int overlap, new_size, alloc_size;
819 uint8_t *buf = *bufp;
823 return AVERROR(EINVAL);
826 buffer_size = s->buf_end - s->buffer;
828 /* the buffers must touch or overlap */
829 if ((buffer_start = s->pos - buffer_size) > buf_size) {
831 return AVERROR(EINVAL);
834 overlap = buf_size - buffer_start;
835 new_size = buf_size + buffer_size - overlap;
837 alloc_size = FFMAX(s->buffer_size, new_size);
838 if (alloc_size > buf_size)
839 if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
840 return AVERROR(ENOMEM);
842 if (new_size > buf_size) {
843 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
848 s->buf_ptr = s->buffer = buf;
849 s->buffer_size = alloc_size;
851 s->buf_end = s->buf_ptr + buf_size;
858 int avio_open(AVIOContext **s, const char *filename, int flags)
860 return avio_open2(s, filename, flags, NULL, NULL);
863 int avio_open2(AVIOContext **s, const char *filename, int flags,
864 const AVIOInterruptCB *int_cb, AVDictionary **options)
869 err = ffurl_open(&h, filename, flags, int_cb, options);
872 err = ffio_fdopen(s, h);
880 int avio_close(AVIOContext *s)
889 av_freep(&s->buffer);
891 av_log(s, AV_LOG_DEBUG, "Statistics: %d seeks, %d writeouts\n", s->seek_count, s->writeout_count);
893 av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
895 return ffurl_close(h);
898 int avio_closep(AVIOContext **s)
900 int ret = avio_close(*s);
905 int avio_printf(AVIOContext *s, const char *fmt, ...)
912 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
914 avio_write(s, buf, strlen(buf));
918 int avio_pause(AVIOContext *s, int pause)
921 return AVERROR(ENOSYS);
922 return s->read_pause(s->opaque, pause);
925 int64_t avio_seek_time(AVIOContext *s, int stream_index,
926 int64_t timestamp, int flags)
928 URLContext *h = s->opaque;
931 return AVERROR(ENOSYS);
932 ret = s->read_seek(h, stream_index, timestamp, flags);
935 s->buf_ptr = s->buf_end; // Flush buffer
936 pos = s->seek(h, 0, SEEK_CUR);
939 else if (pos != AVERROR(ENOSYS))
945 /* output in a dynamic buffer */
947 typedef struct DynBuffer {
948 int pos, size, allocated_size;
951 uint8_t io_buffer[1];
954 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
956 DynBuffer *d = opaque;
957 unsigned new_size, new_allocated_size;
959 /* reallocate buffer if needed */
960 new_size = d->pos + buf_size;
961 new_allocated_size = d->allocated_size;
962 if (new_size < d->pos || new_size > INT_MAX/2)
964 while (new_size > new_allocated_size) {
965 if (!new_allocated_size)
966 new_allocated_size = new_size;
968 new_allocated_size += new_allocated_size / 2 + 1;
971 if (new_allocated_size > d->allocated_size) {
973 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
974 d->allocated_size = 0;
978 d->allocated_size = new_allocated_size;
980 memcpy(d->buffer + d->pos, buf, buf_size);
982 if (d->pos > d->size)
987 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
989 unsigned char buf1[4];
992 /* packetized write: output the header */
993 AV_WB32(buf1, buf_size);
994 ret = dyn_buf_write(opaque, buf1, 4);
999 return dyn_buf_write(opaque, buf, buf_size);
1002 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1004 DynBuffer *d = opaque;
1006 if (whence == SEEK_CUR)
1008 else if (whence == SEEK_END)
1010 if (offset < 0 || offset > 0x7fffffffLL)
1016 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1019 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1021 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1023 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1025 return AVERROR(ENOMEM);
1026 d->io_buffer_size = io_buffer_size;
1027 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
1028 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1029 max_packet_size ? NULL : dyn_buf_seek);
1032 return AVERROR(ENOMEM);
1034 (*s)->max_packet_size = max_packet_size;
1038 int avio_open_dyn_buf(AVIOContext **s)
1040 return url_open_dyn_buf_internal(s, 0);
1043 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1045 if (max_packet_size <= 0)
1047 return url_open_dyn_buf_internal(s, max_packet_size);
1050 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1054 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1063 /* don't attempt to pad fixed-size packet buffers */
1064 if (!s->max_packet_size) {
1065 avio_write(s, padbuf, sizeof(padbuf));
1066 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1071 *pbuffer = d->buffer;
1075 return size - padding;
1078 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1080 DynBuffer *d = opaque;
1083 if (d->pos > d->size)
1088 int ffio_open_null_buf(AVIOContext **s)
1090 int ret = url_open_dyn_buf_internal(s, 0);
1092 AVIOContext *pb = *s;
1093 pb->write_packet = null_buf_write;
1098 int ffio_close_null_buf(AVIOContext *s)
1100 DynBuffer *d = s->opaque;