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 = AVIO_SEEKABLE_NORMAL;
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);
137 static void flush_buffer(AVIOContext *s)
139 if (s->buf_ptr > s->buffer) {
140 writeout(s, s->buffer, s->buf_ptr - s->buffer);
141 if (s->update_checksum) {
142 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
143 s->buf_ptr - s->checksum_ptr);
144 s->checksum_ptr = s->buffer;
147 s->buf_ptr = s->buffer;
150 void avio_w8(AVIOContext *s, int b)
152 av_assert2(b>=-128 && b<=255);
154 if (s->buf_ptr >= s->buf_end)
158 void ffio_fill(AVIOContext *s, int b, int count)
161 int len = FFMIN(s->buf_end - s->buf_ptr, count);
162 memset(s->buf_ptr, b, len);
165 if (s->buf_ptr >= s->buf_end)
172 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
174 if (s->direct && !s->update_checksum) {
176 writeout(s, buf, size);
180 int len = FFMIN(s->buf_end - s->buf_ptr, size);
181 memcpy(s->buf_ptr, buf, len);
184 if (s->buf_ptr >= s->buf_end)
192 void avio_flush(AVIOContext *s)
198 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
202 int force = whence & AVSEEK_FORCE;
203 whence &= ~AVSEEK_FORCE;
206 return AVERROR(EINVAL);
208 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
210 if (whence != SEEK_CUR && whence != SEEK_SET)
211 return AVERROR(EINVAL);
213 if (whence == SEEK_CUR) {
214 offset1 = pos + (s->buf_ptr - s->buffer);
219 offset1 = offset - pos;
220 if (!s->must_flush && (!s->direct || !s->seek) &&
221 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
222 /* can do the seek inside the buffer */
223 s->buf_ptr = s->buffer + offset1;
224 } else if ((!s->seekable ||
225 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
226 !s->write_flag && offset1 >= 0 &&
227 (!s->direct || !s->seek) &&
228 (whence != SEEK_END || force)) {
229 while(s->pos < offset && !s->eof_reached)
233 s->buf_ptr = s->buf_end + offset - s->pos;
242 return AVERROR(EPIPE);
243 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
247 s->buf_end = s->buffer;
248 s->buf_ptr = s->buffer;
255 int64_t avio_skip(AVIOContext *s, int64_t offset)
257 return avio_seek(s, offset, SEEK_CUR);
260 int64_t avio_size(AVIOContext *s)
265 return AVERROR(EINVAL);
268 return AVERROR(ENOSYS);
269 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
271 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
274 s->seek(s->opaque, s->pos, SEEK_SET);
279 int url_feof(AVIOContext *s)
287 return s->eof_reached;
290 void avio_wl32(AVIOContext *s, unsigned int val)
292 avio_w8(s, (uint8_t) val );
293 avio_w8(s, (uint8_t)(val >> 8 ));
294 avio_w8(s, (uint8_t)(val >> 16));
295 avio_w8(s, val >> 24 );
298 void avio_wb32(AVIOContext *s, unsigned int val)
300 avio_w8(s, val >> 24 );
301 avio_w8(s, (uint8_t)(val >> 16));
302 avio_w8(s, (uint8_t)(val >> 8 ));
303 avio_w8(s, (uint8_t) val );
306 int avio_put_str(AVIOContext *s, const char *str)
311 avio_write(s, (const unsigned char *) str, len);
317 int avio_put_str16le(AVIOContext *s, const char *str)
319 const uint8_t *q = str;
326 GET_UTF8(ch, *q++, break;)
327 PUT_UTF16(ch, tmp, avio_wl16(s, tmp); ret += 2;)
334 int ff_get_v_length(uint64_t val)
344 void ff_put_v(AVIOContext *bc, uint64_t val)
346 int i = ff_get_v_length(val);
349 avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
351 avio_w8(bc, val & 127);
354 void avio_wl64(AVIOContext *s, uint64_t val)
356 avio_wl32(s, (uint32_t)(val & 0xffffffff));
357 avio_wl32(s, (uint32_t)(val >> 32));
360 void avio_wb64(AVIOContext *s, uint64_t val)
362 avio_wb32(s, (uint32_t)(val >> 32));
363 avio_wb32(s, (uint32_t)(val & 0xffffffff));
366 void avio_wl16(AVIOContext *s, unsigned int val)
368 avio_w8(s, (uint8_t)val);
369 avio_w8(s, (int)val >> 8);
372 void avio_wb16(AVIOContext *s, unsigned int val)
374 avio_w8(s, (int)val >> 8);
375 avio_w8(s, (uint8_t)val);
378 void avio_wl24(AVIOContext *s, unsigned int val)
380 avio_wl16(s, val & 0xffff);
381 avio_w8(s, (int)val >> 16);
384 void avio_wb24(AVIOContext *s, unsigned int val)
386 avio_wb16(s, (int)val >> 8);
387 avio_w8(s, (uint8_t)val);
392 static void fill_buffer(AVIOContext *s)
394 uint8_t *dst = !s->max_packet_size &&
395 s->buf_end - s->buffer < s->buffer_size ?
396 s->buf_end : s->buffer;
397 int len = s->buffer_size - (dst - s->buffer);
398 int max_buffer_size = s->max_packet_size ?
399 s->max_packet_size : IO_BUFFER_SIZE;
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 ffio_set_buf_size(s, max_buffer_size);
420 s->checksum_ptr = dst = s->buffer;
421 len = s->buffer_size;
425 len = s->read_packet(s->opaque, dst, len);
429 /* do not modify buffer if EOF reached so that a seek back can
430 be done without rereading data */
437 s->buf_end = dst + len;
438 s->bytes_read += len;
442 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
445 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
448 unsigned long ffio_get_checksum(AVIOContext *s)
450 s->checksum = s->update_checksum(s->checksum, s->checksum_ptr,
451 s->buf_ptr - s->checksum_ptr);
452 s->update_checksum = NULL;
456 void ffio_init_checksum(AVIOContext *s,
457 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
458 unsigned long checksum)
460 s->update_checksum = update_checksum;
461 if (s->update_checksum) {
462 s->checksum = checksum;
463 s->checksum_ptr = s->buf_ptr;
467 /* XXX: put an inline version */
468 int avio_r8(AVIOContext *s)
470 if (s->buf_ptr >= s->buf_end)
472 if (s->buf_ptr < s->buf_end)
473 return *s->buf_ptr++;
477 int avio_read(AVIOContext *s, unsigned char *buf, int size)
483 len = s->buf_end - s->buf_ptr;
486 if (len == 0 || s->write_flag) {
487 if((s->direct || size > s->buffer_size) && !s->update_checksum){
489 len = s->read_packet(s->opaque, buf, size);
491 /* do not modify buffer if EOF reached so that a seek back can
492 be done without rereading data */
499 s->bytes_read += len;
502 s->buf_ptr = s->buffer;
503 s->buf_end = s->buffer/* + len*/;
507 len = s->buf_end - s->buf_ptr;
512 memcpy(buf, s->buf_ptr, len);
519 if (s->error) return s->error;
520 if (url_feof(s)) return AVERROR_EOF;
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 (url_feof(s)) 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 (void*)ffurl_read, (void*)ffurl_write, (void*)ffurl_seek);
712 return AVERROR(ENOMEM);
714 (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
715 (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
716 (*s)->max_packet_size = max_packet_size;
718 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
719 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
721 (*s)->av_class = &ffio_url_class;
725 int ffio_set_buf_size(AVIOContext *s, int buf_size)
728 buffer = av_malloc(buf_size);
730 return AVERROR(ENOMEM);
734 s->buffer_size = buf_size;
736 url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
740 static int url_resetbuf(AVIOContext *s, int flags)
742 av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
744 if (flags & AVIO_FLAG_WRITE) {
745 s->buf_end = s->buffer + s->buffer_size;
748 s->buf_end = s->buffer;
754 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
756 int64_t buffer_start;
758 int overlap, new_size, alloc_size;
759 uint8_t *buf = *bufp;
763 return AVERROR(EINVAL);
766 buffer_size = s->buf_end - s->buffer;
768 /* the buffers must touch or overlap */
769 if ((buffer_start = s->pos - buffer_size) > buf_size) {
771 return AVERROR(EINVAL);
774 overlap = buf_size - buffer_start;
775 new_size = buf_size + buffer_size - overlap;
777 alloc_size = FFMAX(s->buffer_size, new_size);
778 if (alloc_size > buf_size)
779 if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
780 return AVERROR(ENOMEM);
782 if (new_size > buf_size) {
783 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
788 s->buf_ptr = s->buffer = buf;
789 s->buffer_size = alloc_size;
791 s->buf_end = s->buf_ptr + buf_size;
798 int avio_open(AVIOContext **s, const char *filename, int flags)
800 return avio_open2(s, filename, flags, NULL, NULL);
803 int avio_open2(AVIOContext **s, const char *filename, int flags,
804 const AVIOInterruptCB *int_cb, AVDictionary **options)
809 err = ffurl_open(&h, filename, flags, int_cb, options);
812 err = ffio_fdopen(s, h);
820 int avio_close(AVIOContext *s)
829 av_freep(&s->buffer);
831 av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
833 return ffurl_close(h);
836 int avio_closep(AVIOContext **s)
838 int ret = avio_close(*s);
843 int avio_printf(AVIOContext *s, const char *fmt, ...)
850 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
852 avio_write(s, buf, strlen(buf));
856 int avio_pause(AVIOContext *s, int pause)
859 return AVERROR(ENOSYS);
860 return s->read_pause(s->opaque, pause);
863 int64_t avio_seek_time(AVIOContext *s, int stream_index,
864 int64_t timestamp, int flags)
866 URLContext *h = s->opaque;
869 return AVERROR(ENOSYS);
870 ret = s->read_seek(h, stream_index, timestamp, flags);
873 s->buf_ptr = s->buf_end; // Flush buffer
874 pos = s->seek(h, 0, SEEK_CUR);
877 else if (pos != AVERROR(ENOSYS))
883 /* output in a dynamic buffer */
885 typedef struct DynBuffer {
886 int pos, size, allocated_size;
889 uint8_t io_buffer[1];
892 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
894 DynBuffer *d = opaque;
895 unsigned new_size, new_allocated_size;
897 /* reallocate buffer if needed */
898 new_size = d->pos + buf_size;
899 new_allocated_size = d->allocated_size;
900 if (new_size < d->pos || new_size > INT_MAX/2)
902 while (new_size > new_allocated_size) {
903 if (!new_allocated_size)
904 new_allocated_size = new_size;
906 new_allocated_size += new_allocated_size / 2 + 1;
909 if (new_allocated_size > d->allocated_size) {
910 d->buffer = av_realloc_f(d->buffer, 1, new_allocated_size);
911 if(d->buffer == NULL)
912 return AVERROR(ENOMEM);
913 d->allocated_size = new_allocated_size;
915 memcpy(d->buffer + d->pos, buf, buf_size);
917 if (d->pos > d->size)
922 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
924 unsigned char buf1[4];
927 /* packetized write: output the header */
928 AV_WB32(buf1, buf_size);
929 ret = dyn_buf_write(opaque, buf1, 4);
934 return dyn_buf_write(opaque, buf, buf_size);
937 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
939 DynBuffer *d = opaque;
941 if (whence == SEEK_CUR)
943 else if (whence == SEEK_END)
945 if (offset < 0 || offset > 0x7fffffffLL)
951 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
954 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
956 if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
958 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
960 return AVERROR(ENOMEM);
961 d->io_buffer_size = io_buffer_size;
962 *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
963 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
964 max_packet_size ? NULL : dyn_buf_seek);
967 return AVERROR(ENOMEM);
969 (*s)->max_packet_size = max_packet_size;
973 int avio_open_dyn_buf(AVIOContext **s)
975 return url_open_dyn_buf_internal(s, 0);
978 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
980 if (max_packet_size <= 0)
982 return url_open_dyn_buf_internal(s, max_packet_size);
985 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
987 DynBuffer *d = s->opaque;
989 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
992 /* don't attempt to pad fixed-size packet buffers */
993 if (!s->max_packet_size) {
994 avio_write(s, padbuf, sizeof(padbuf));
995 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1000 *pbuffer = d->buffer;
1004 return size - padding;