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 static void *ff_avio_child_next(void *obj, void *prev)
46 return prev ? NULL : s->opaque;
49 static const AVClass *ff_avio_child_class_next(const AVClass *prev)
51 return prev ? NULL : &ffurl_context_class;
54 static const AVOption ff_avio_options[] = {
58 const AVClass ff_avio_class = {
59 .class_name = "AVIOContext",
60 .item_name = av_default_item_name,
61 .version = LIBAVUTIL_VERSION_INT,
62 .option = ff_avio_options,
63 .child_next = ff_avio_child_next,
64 .child_class_next = ff_avio_child_class_next,
67 static void fill_buffer(AVIOContext *s);
68 static int url_resetbuf(AVIOContext *s, int flags);
70 int ffio_init_context(AVIOContext *s,
71 unsigned char *buffer,
75 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
76 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
77 int64_t (*seek)(void *opaque, int64_t offset, int whence))
80 s->buffer_size = buffer_size;
84 url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
86 s->write_packet = write_packet;
87 s->read_packet = read_packet;
93 s->seekable = seek ? AVIO_SEEKABLE_NORMAL : 0;
94 s->max_packet_size = 0;
95 s->update_checksum = NULL;
97 if (!read_packet && !write_flag) {
99 s->buf_end = s->buffer + buffer_size;
101 s->read_pause = NULL;
107 AVIOContext *avio_alloc_context(
108 unsigned char *buffer,
112 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
113 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
114 int64_t (*seek)(void *opaque, int64_t offset, int whence))
116 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
119 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
120 read_packet, write_packet, seek);
124 static void flush_buffer(AVIOContext *s)
126 if (s->buf_ptr > s->buffer) {
127 if (s->write_packet && !s->error) {
128 int ret = s->write_packet(s->opaque, s->buffer,
129 s->buf_ptr - s->buffer);
134 if (s->update_checksum) {
135 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
136 s->buf_ptr - s->checksum_ptr);
137 s->checksum_ptr = s->buffer;
139 s->pos += s->buf_ptr - s->buffer;
141 s->buf_ptr = s->buffer;
144 void avio_w8(AVIOContext *s, int b)
147 if (s->buf_ptr >= s->buf_end)
151 void ffio_fill(AVIOContext *s, int b, int count)
154 int len = FFMIN(s->buf_end - s->buf_ptr, count);
155 memset(s->buf_ptr, b, len);
158 if (s->buf_ptr >= s->buf_end)
165 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
168 int len = FFMIN(s->buf_end - s->buf_ptr, size);
169 memcpy(s->buf_ptr, buf, len);
172 if (s->buf_ptr >= s->buf_end)
180 void avio_flush(AVIOContext *s)
186 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
190 int force = whence & AVSEEK_FORCE;
191 whence &= ~AVSEEK_FORCE;
194 return AVERROR(EINVAL);
196 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
198 if (whence != SEEK_CUR && whence != SEEK_SET)
199 return AVERROR(EINVAL);
201 if (whence == SEEK_CUR) {
202 offset1 = pos + (s->buf_ptr - s->buffer);
207 offset1 = offset - pos;
208 if (!s->must_flush &&
209 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
210 /* can do the seek inside the buffer */
211 s->buf_ptr = s->buffer + offset1;
212 } else if ((!s->seekable ||
213 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
214 !s->write_flag && offset1 >= 0 &&
215 (whence != SEEK_END || force)) {
216 while(s->pos < offset && !s->eof_reached)
220 s->buf_ptr = s->buf_end + offset - s->pos;
229 return AVERROR(EPIPE);
230 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
233 s->buf_end = s->buffer;
234 s->buf_ptr = s->buffer;
241 int64_t avio_size(AVIOContext *s)
246 return AVERROR(EINVAL);
249 return AVERROR(ENOSYS);
250 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
252 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
255 s->seek(s->opaque, s->pos, SEEK_SET);
260 void avio_wl32(AVIOContext *s, unsigned int val)
263 avio_w8(s, val >> 8);
264 avio_w8(s, val >> 16);
265 avio_w8(s, val >> 24);
268 void avio_wb32(AVIOContext *s, unsigned int val)
270 avio_w8(s, val >> 24);
271 avio_w8(s, val >> 16);
272 avio_w8(s, val >> 8);
276 int avio_put_str(AVIOContext *s, const char *str)
281 avio_write(s, (const unsigned char *) str, len);
287 #define PUT_STR16(type, write) \
288 int avio_put_str16 ## type(AVIOContext * s, const char *str) \
290 const uint8_t *q = str; \
297 GET_UTF8(ch, *q++, break; ) \
298 PUT_UTF16(ch, tmp, write(s, tmp); ret += 2; ) \
305 PUT_STR16(le, avio_wl16)
306 PUT_STR16(be, avio_wb16)
310 int ff_get_v_length(uint64_t val)
320 void ff_put_v(AVIOContext *bc, uint64_t val)
322 int i = ff_get_v_length(val);
325 avio_w8(bc, 128 | (val >> (7 * i)));
327 avio_w8(bc, val & 127);
330 void avio_wl64(AVIOContext *s, uint64_t val)
332 avio_wl32(s, (uint32_t)(val & 0xffffffff));
333 avio_wl32(s, (uint32_t)(val >> 32));
336 void avio_wb64(AVIOContext *s, uint64_t val)
338 avio_wb32(s, (uint32_t)(val >> 32));
339 avio_wb32(s, (uint32_t)(val & 0xffffffff));
342 void avio_wl16(AVIOContext *s, unsigned int val)
345 avio_w8(s, val >> 8);
348 void avio_wb16(AVIOContext *s, unsigned int val)
350 avio_w8(s, val >> 8);
354 void avio_wl24(AVIOContext *s, unsigned int val)
356 avio_wl16(s, val & 0xffff);
357 avio_w8(s, val >> 16);
360 void avio_wb24(AVIOContext *s, unsigned int val)
362 avio_wb16(s, val >> 8);
368 static void fill_buffer(AVIOContext *s)
370 uint8_t *dst = !s->max_packet_size &&
371 s->buf_end - s->buffer < s->buffer_size ?
372 s->buf_end : s->buffer;
373 int len = s->buffer_size - (dst - s->buffer);
374 int max_buffer_size = s->max_packet_size ?
375 s->max_packet_size : IO_BUFFER_SIZE;
377 /* can't fill the buffer without read_packet, just set EOF if appropriate */
378 if (!s->read_packet && s->buf_ptr >= s->buf_end)
381 /* no need to do anything if EOF already reached */
385 if (s->update_checksum && dst == s->buffer) {
386 if (s->buf_end > s->checksum_ptr)
387 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
388 s->buf_end - s->checksum_ptr);
389 s->checksum_ptr = s->buffer;
392 /* make buffer smaller in case it ended up large after probing */
393 if (s->buffer_size > max_buffer_size) {
394 ffio_set_buf_size(s, max_buffer_size);
396 s->checksum_ptr = dst = s->buffer;
397 len = s->buffer_size;
401 len = s->read_packet(s->opaque, dst, len);
405 /* do not modify buffer if EOF reached so that a seek back can
406 be done without rereading data */
413 s->buf_end = dst + len;
417 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
420 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
423 unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf,
426 return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len);
429 unsigned long ffio_get_checksum(AVIOContext *s)
431 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
432 s->buf_ptr - s->checksum_ptr);
433 s->update_checksum = NULL;
437 void ffio_init_checksum(AVIOContext *s,
438 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
439 unsigned long checksum)
441 s->update_checksum = update_checksum;
442 if (s->update_checksum) {
443 s->checksum = checksum;
444 s->checksum_ptr = s->buf_ptr;
448 /* XXX: put an inline version */
449 int avio_r8(AVIOContext *s)
451 if (s->buf_ptr >= s->buf_end)
453 if (s->buf_ptr < s->buf_end)
454 return *s->buf_ptr++;
458 int avio_read(AVIOContext *s, unsigned char *buf, int size)
464 len = s->buf_end - s->buf_ptr;
467 if (len == 0 || s->write_flag) {
468 if(size > s->buffer_size && !s->update_checksum){
470 len = s->read_packet(s->opaque, buf, size);
472 /* do not modify buffer if EOF reached so that a seek back can
473 be done without rereading data */
482 s->buf_ptr = s->buffer;
483 s->buf_end = s->buffer/* + len*/;
487 len = s->buf_end - s->buf_ptr;
492 memcpy(buf, s->buf_ptr, len);
499 if (s->error) return s->error;
500 if (s->eof_reached) return AVERROR_EOF;
505 int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
507 int ret = avio_read(s, buf, size);
509 return AVERROR_INVALIDDATA;
513 int ffio_read_indirect(AVIOContext *s, unsigned char *buf, int size, const unsigned char **data)
515 if (s->buf_end - s->buf_ptr >= size && !s->write_flag) {
521 return avio_read(s, buf, size);
525 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
532 if (s->read_packet && s->write_flag) {
533 len = s->read_packet(s->opaque, buf, size);
539 len = s->buf_end - s->buf_ptr;
541 /* Reset the buf_end pointer to the start of the buffer, to make sure
542 * the fill_buffer call tries to read as much data as fits into the
543 * full buffer, instead of just what space is left after buf_end.
544 * This avoids returning partial packets at the end of the buffer,
545 * for packet based inputs.
547 s->buf_end = s->buf_ptr = s->buffer;
549 len = s->buf_end - s->buf_ptr;
553 memcpy(buf, s->buf_ptr, len);
556 if (s->error) return s->error;
557 if (s->eof_reached) return AVERROR_EOF;
562 unsigned int avio_rl16(AVIOContext *s)
566 val |= avio_r8(s) << 8;
570 unsigned int avio_rl24(AVIOContext *s)
574 val |= avio_r8(s) << 16;
578 unsigned int avio_rl32(AVIOContext *s)
582 val |= avio_rl16(s) << 16;
586 uint64_t avio_rl64(AVIOContext *s)
589 val = (uint64_t)avio_rl32(s);
590 val |= (uint64_t)avio_rl32(s) << 32;
594 unsigned int avio_rb16(AVIOContext *s)
597 val = avio_r8(s) << 8;
602 unsigned int avio_rb24(AVIOContext *s)
605 val = avio_rb16(s) << 8;
609 unsigned int avio_rb32(AVIOContext *s)
612 val = avio_rb16(s) << 16;
617 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
624 if (c && i < maxlen-1)
626 } while (c != '\n' && c);
632 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
637 return AVERROR(EINVAL);
638 // reserve 1 byte for terminating 0
639 buflen = FFMIN(buflen - 1, maxlen);
640 for (i = 0; i < buflen; i++)
641 if (!(buf[i] = avio_r8(s)))
644 for (; i < maxlen; i++)
650 #define GET_STR16(type, read) \
651 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
656 return AVERROR(EINVAL); \
657 while (ret + 1 < maxlen) {\
660 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
663 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
669 GET_STR16(le, avio_rl16)
670 GET_STR16(be, avio_rb16)
674 uint64_t avio_rb64(AVIOContext *s)
677 val = (uint64_t)avio_rb32(s) << 32;
678 val |= (uint64_t)avio_rb32(s);
682 uint64_t ffio_read_varlen(AVIOContext *bc){
688 val= (val<<7) + (tmp&127);
693 int ffio_fdopen(AVIOContext **s, URLContext *h)
696 int buffer_size, max_packet_size;
698 max_packet_size = h->max_packet_size;
699 if (max_packet_size) {
700 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
702 buffer_size = IO_BUFFER_SIZE;
704 buffer = av_malloc(buffer_size);
706 return AVERROR(ENOMEM);
708 *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
709 (int (*)(void *, uint8_t *, int)) ffurl_read,
710 (int (*)(void *, uint8_t *, int)) ffurl_write,
711 (int64_t (*)(void *, int64_t, int)) ffurl_seek);
714 return AVERROR(ENOMEM);
716 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
717 (*s)->max_packet_size = max_packet_size;
719 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
720 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
722 (*s)->av_class = &ff_avio_class;
726 int ffio_set_buf_size(AVIOContext *s, int buf_size)
729 buffer = av_malloc(buf_size);
731 return AVERROR(ENOMEM);
735 s->buffer_size = buf_size;
737 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
741 static int url_resetbuf(AVIOContext *s, int flags)
743 assert(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
745 if (flags & AVIO_FLAG_WRITE) {
746 s->buf_end = s->buffer + s->buffer_size;
749 s->buf_end = s->buffer;
755 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
757 int64_t buffer_start;
759 int overlap, new_size, alloc_size;
762 return AVERROR(EINVAL);
764 buffer_size = s->buf_end - s->buffer;
766 /* the buffers must touch or overlap */
767 if ((buffer_start = s->pos - buffer_size) > buf_size)
768 return AVERROR(EINVAL);
770 overlap = buf_size - buffer_start;
771 new_size = buf_size + buffer_size - overlap;
773 alloc_size = FFMAX(s->buffer_size, new_size);
774 if (alloc_size > buf_size)
775 if (!(buf = av_realloc(buf, alloc_size)))
776 return AVERROR(ENOMEM);
778 if (new_size > buf_size) {
779 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
784 s->buf_ptr = s->buffer = buf;
785 s->buffer_size = alloc_size;
787 s->buf_end = s->buf_ptr + buf_size;
794 int avio_open(AVIOContext **s, const char *filename, int flags)
796 return avio_open2(s, filename, flags, NULL, NULL);
799 int avio_open2(AVIOContext **s, const char *filename, int flags,
800 const AVIOInterruptCB *int_cb, AVDictionary **options)
805 err = ffurl_open(&h, filename, flags, int_cb, options);
808 err = ffio_fdopen(s, h);
816 int avio_close(AVIOContext *s)
825 av_freep(&s->buffer);
827 return ffurl_close(h);
830 int avio_closep(AVIOContext **s)
832 int ret = avio_close(*s);
837 int avio_printf(AVIOContext *s, const char *fmt, ...)
844 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
846 avio_write(s, buf, strlen(buf));
850 int avio_pause(AVIOContext *s, int pause)
853 return AVERROR(ENOSYS);
854 return s->read_pause(s->opaque, pause);
857 int64_t avio_seek_time(AVIOContext *s, int stream_index,
858 int64_t timestamp, int flags)
860 URLContext *h = s->opaque;
863 return AVERROR(ENOSYS);
864 ret = s->read_seek(h, stream_index, timestamp, flags);
867 s->buf_ptr = s->buf_end; // Flush buffer
868 pos = s->seek(h, 0, SEEK_CUR);
871 else if (pos != AVERROR(ENOSYS))
877 /* output in a dynamic buffer */
879 typedef struct DynBuffer {
880 int pos, size, allocated_size;
883 uint8_t io_buffer[1];
886 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
888 DynBuffer *d = opaque;
889 unsigned new_size, new_allocated_size;
891 /* reallocate buffer if needed */
892 new_size = d->pos + buf_size;
893 new_allocated_size = d->allocated_size;
894 if (new_size < d->pos || new_size > INT_MAX/2)
896 while (new_size > new_allocated_size) {
897 if (!new_allocated_size)
898 new_allocated_size = new_size;
900 new_allocated_size += new_allocated_size / 2 + 1;
903 if (new_allocated_size > d->allocated_size) {
905 if ((err = av_reallocp(&d->buffer, new_allocated_size)) < 0) {
906 d->allocated_size = 0;
910 d->allocated_size = new_allocated_size;
912 memcpy(d->buffer + d->pos, buf, buf_size);
914 if (d->pos > d->size)
919 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
921 unsigned char buf1[4];
924 /* packetized write: output the header */
925 AV_WB32(buf1, buf_size);
926 ret = dyn_buf_write(opaque, buf1, 4);
931 return dyn_buf_write(opaque, buf, buf_size);
934 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
936 DynBuffer *d = opaque;
938 if (whence == SEEK_CUR)
940 else if (whence == SEEK_END)
942 if (offset < 0 || offset > 0x7fffffffLL)
948 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
951 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
953 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
955 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
957 return AVERROR(ENOMEM);
958 d->io_buffer_size = io_buffer_size;
959 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
960 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
961 max_packet_size ? NULL : dyn_buf_seek);
964 return AVERROR(ENOMEM);
966 (*s)->max_packet_size = max_packet_size;
970 int avio_open_dyn_buf(AVIOContext **s)
972 return url_open_dyn_buf_internal(s, 0);
975 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
977 if (max_packet_size <= 0)
979 return url_open_dyn_buf_internal(s, max_packet_size);
982 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
986 static const char padbuf[AV_INPUT_BUFFER_PADDING_SIZE] = {0};
994 /* don't attempt to pad fixed-size packet buffers */
995 if (!s->max_packet_size) {
996 avio_write(s, padbuf, sizeof(padbuf));
997 padding = AV_INPUT_BUFFER_PADDING_SIZE;
1003 *pbuffer = d->buffer;
1007 return size - padding;
1010 void ffio_free_dyn_buf(AVIOContext **s)
1015 avio_close_dyn_buf(*s, &tmp);
1020 static int null_buf_write(void *opaque, uint8_t *buf, int buf_size)
1022 DynBuffer *d = opaque;
1025 if (d->pos > d->size)
1030 int ffio_open_null_buf(AVIOContext **s)
1032 int ret = url_open_dyn_buf_internal(s, 0);
1034 AVIOContext *pb = *s;
1035 pb->write_packet = null_buf_write;
1040 int ffio_close_null_buf(AVIOContext *s)
1042 DynBuffer *d = s->opaque;