2 * Buffered I/O for ffmpeg system
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/intreadwrite.h"
26 #include "avio_internal.h"
30 #define IO_BUFFER_SIZE 32768
33 * Do seeks within this distance ahead of the current buffer by skipping
34 * data instead of calling the protocol seek function, for seekable
37 #define SHORT_SEEK_THRESHOLD 4096
39 static void fill_buffer(AVIOContext *s);
40 #if !FF_API_URL_RESETBUF
41 static int url_resetbuf(AVIOContext *s, int flags);
44 int ffio_init_context(AVIOContext *s,
45 unsigned char *buffer,
49 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
50 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
51 int64_t (*seek)(void *opaque, int64_t offset, int whence))
54 s->buffer_size = buffer_size;
57 url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
58 s->write_packet = write_packet;
59 s->read_packet = read_packet;
66 s->max_packet_size = 0;
67 s->update_checksum= NULL;
68 if(!read_packet && !write_flag){
70 s->buf_end = s->buffer + buffer_size;
78 int init_put_byte(AVIOContext *s,
79 unsigned char *buffer,
83 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
84 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
85 int64_t (*seek)(void *opaque, int64_t offset, int whence))
87 return ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
88 read_packet, write_packet, seek);
90 AVIOContext *av_alloc_put_byte(
91 unsigned char *buffer,
95 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
96 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
97 int64_t (*seek)(void *opaque, int64_t offset, int whence))
99 return avio_alloc_context(buffer, buffer_size, write_flag, opaque,
100 read_packet, write_packet, seek);
104 AVIOContext *avio_alloc_context(
105 unsigned char *buffer,
109 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
110 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
111 int64_t (*seek)(void *opaque, int64_t offset, int whence))
113 AVIOContext *s = av_mallocz(sizeof(AVIOContext));
114 ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
115 read_packet, write_packet, seek);
119 static void flush_buffer(AVIOContext *s)
121 if (s->buf_ptr > s->buffer) {
122 if (s->write_packet && !s->error){
123 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
128 if(s->update_checksum){
129 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
130 s->checksum_ptr= s->buffer;
132 s->pos += s->buf_ptr - s->buffer;
134 s->buf_ptr = s->buffer;
137 void avio_w8(AVIOContext *s, int b)
140 if (s->buf_ptr >= s->buf_end)
144 void ffio_fill(AVIOContext *s, int b, int count)
147 int len = FFMIN(s->buf_end - s->buf_ptr, count);
148 memset(s->buf_ptr, b, len);
151 if (s->buf_ptr >= s->buf_end)
158 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
161 int len = FFMIN(s->buf_end - s->buf_ptr, size);
162 memcpy(s->buf_ptr, buf, len);
165 if (s->buf_ptr >= s->buf_end)
173 void put_flush_packet(AVIOContext *s)
179 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
183 int force = whence & AVSEEK_FORCE;
184 whence &= ~AVSEEK_FORCE;
187 return AVERROR(EINVAL);
189 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
191 if (whence != SEEK_CUR && whence != SEEK_SET)
192 return AVERROR(EINVAL);
194 if (whence == SEEK_CUR) {
195 offset1 = pos + (s->buf_ptr - s->buffer);
200 offset1 = offset - pos;
201 if (!s->must_flush &&
202 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
203 /* can do the seek inside the buffer */
204 s->buf_ptr = s->buffer + offset1;
205 } else if ((s->is_streamed ||
206 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
207 !s->write_flag && offset1 >= 0 &&
208 (whence != SEEK_END || force)) {
209 while(s->pos < offset && !s->eof_reached)
213 s->buf_ptr = s->buf_end + offset - s->pos;
217 #if CONFIG_MUXERS || CONFIG_NETWORK
222 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
224 return AVERROR(EPIPE);
225 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
228 s->buf_end = s->buffer;
229 s->buf_ptr = s->buffer;
237 int url_fskip(AVIOContext *s, int64_t offset)
239 int64_t ret = avio_seek(s, offset, SEEK_CUR);
240 return ret < 0 ? ret : 0;
243 int64_t url_ftell(AVIOContext *s)
245 return avio_seek(s, 0, SEEK_CUR);
249 int64_t avio_size(AVIOContext *s)
254 return AVERROR(EINVAL);
257 return AVERROR(ENOSYS);
258 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
260 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
263 s->seek(s->opaque, s->pos, SEEK_SET);
269 int url_feof(AVIOContext *s)
273 return s->eof_reached;
276 int url_ferror(AVIOContext *s)
284 void avio_wl32(AVIOContext *s, unsigned int val)
287 avio_w8(s, val >> 8);
288 avio_w8(s, val >> 16);
289 avio_w8(s, val >> 24);
292 void avio_wb32(AVIOContext *s, unsigned int val)
294 avio_w8(s, val >> 24);
295 avio_w8(s, val >> 16);
296 avio_w8(s, val >> 8);
301 void put_strz(AVIOContext *s, const char *str)
303 avio_put_str(s, str);
306 #define GET(name, type) \
307 type get_be ##name(AVIOContext *s) \
309 return avio_rb ##name(s);\
311 type get_le ##name(AVIOContext *s) \
313 return avio_rl ##name(s);\
316 GET(16, unsigned int)
317 GET(24, unsigned int)
318 GET(32, unsigned int)
323 #define PUT(name, type ) \
324 void put_le ##name(AVIOContext *s, type val)\
326 avio_wl ##name(s, val);\
328 void put_be ##name(AVIOContext *s, type val)\
330 avio_wb ##name(s, val);\
333 PUT(16, unsigned int)
334 PUT(24, unsigned int)
335 PUT(32, unsigned int)
339 int get_byte(AVIOContext *s)
343 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
345 return avio_read(s, buf, size);
347 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
349 return ffio_read_partial(s, buf, size);
351 void put_byte(AVIOContext *s, int val)
355 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
357 avio_write(s, buf, size);
359 void put_nbyte(AVIOContext *s, int b, int count)
361 ffio_fill(s, b, count);
364 int url_fopen(AVIOContext **s, const char *filename, int flags)
366 return avio_open(s, filename, flags);
368 int url_fclose(AVIOContext *s)
370 return avio_close(s);
372 int64_t url_fseek(AVIOContext *s, int64_t offset, int whence)
374 return avio_seek(s, offset, whence);
376 int64_t url_fsize(AVIOContext *s)
380 int url_setbufsize(AVIOContext *s, int buf_size)
382 return ffio_set_buf_size(s, buf_size);
384 int url_fprintf(AVIOContext *s, const char *fmt, ...)
391 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
393 avio_write(s, buf, strlen(buf));
398 int avio_put_str(AVIOContext *s, const char *str)
403 avio_write(s, (const unsigned char *) str, len);
409 int avio_put_str16le(AVIOContext *s, const char *str)
411 const uint8_t *q = str;
418 GET_UTF8(ch, *q++, break;)
419 PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
426 int ff_get_v_length(uint64_t val){
435 void ff_put_v(AVIOContext *bc, uint64_t val){
436 int i= ff_get_v_length(val);
439 avio_w8(bc, 128 | (val>>(7*i)));
441 avio_w8(bc, val&127);
444 void avio_wl64(AVIOContext *s, uint64_t val)
446 avio_wl32(s, (uint32_t)(val & 0xffffffff));
447 avio_wl32(s, (uint32_t)(val >> 32));
450 void avio_wb64(AVIOContext *s, uint64_t val)
452 avio_wb32(s, (uint32_t)(val >> 32));
453 avio_wb32(s, (uint32_t)(val & 0xffffffff));
456 void avio_wl16(AVIOContext *s, unsigned int val)
459 avio_w8(s, val >> 8);
462 void avio_wb16(AVIOContext *s, unsigned int val)
464 avio_w8(s, val >> 8);
468 void avio_wl24(AVIOContext *s, unsigned int val)
470 avio_wl16(s, val & 0xffff);
471 avio_w8(s, val >> 16);
474 void avio_wb24(AVIOContext *s, unsigned int val)
476 avio_wb16(s, val >> 8);
481 void put_tag(AVIOContext *s, const char *tag)
491 static void fill_buffer(AVIOContext *s)
493 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_end : s->buffer;
494 int len= s->buffer_size - (dst - s->buffer);
495 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
497 /* no need to do anything if EOF already reached */
501 if(s->update_checksum && dst == s->buffer){
502 if(s->buf_end > s->checksum_ptr)
503 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
504 s->checksum_ptr= s->buffer;
507 /* make buffer smaller in case it ended up large after probing */
508 if (s->buffer_size > max_buffer_size) {
509 ffio_set_buf_size(s, max_buffer_size);
511 s->checksum_ptr = dst = s->buffer;
512 len = s->buffer_size;
516 len = s->read_packet(s->opaque, dst, len);
520 /* do not modify buffer if EOF reached so that a seek back can
521 be done without rereading data */
528 s->buf_end = dst + len;
532 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
535 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
538 unsigned long get_checksum(AVIOContext *s)
540 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
541 s->update_checksum= NULL;
545 void init_checksum(AVIOContext *s,
546 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
547 unsigned long checksum)
549 s->update_checksum= update_checksum;
550 if(s->update_checksum){
551 s->checksum= checksum;
552 s->checksum_ptr= s->buf_ptr;
556 /* XXX: put an inline version */
557 int avio_r8(AVIOContext *s)
559 if (s->buf_ptr >= s->buf_end)
561 if (s->buf_ptr < s->buf_end)
562 return *s->buf_ptr++;
567 int url_fgetc(AVIOContext *s)
569 if (s->buf_ptr >= s->buf_end)
571 if (s->buf_ptr < s->buf_end)
572 return *s->buf_ptr++;
577 int avio_read(AVIOContext *s, unsigned char *buf, int size)
583 len = s->buf_end - s->buf_ptr;
587 if(size > s->buffer_size && !s->update_checksum){
589 len = s->read_packet(s->opaque, buf, size);
591 /* do not modify buffer if EOF reached so that a seek back can
592 be done without rereading data */
601 s->buf_ptr = s->buffer;
602 s->buf_end = s->buffer/* + len*/;
606 len = s->buf_end - s->buf_ptr;
611 memcpy(buf, s->buf_ptr, len);
618 if (s->error) return s->error;
619 if (s->eof_reached) return AVERROR_EOF;
624 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
631 len = s->buf_end - s->buf_ptr;
634 len = s->buf_end - s->buf_ptr;
638 memcpy(buf, s->buf_ptr, len);
641 if (s->error) return s->error;
642 if (s->eof_reached) 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;
703 char *get_strz(AVIOContext *s, char *buf, int maxlen)
705 avio_get_str(s, INT_MAX, buf, maxlen);
710 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
717 if (c && i < maxlen-1)
719 } while (c != '\n' && c);
725 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
729 // reserve 1 byte for terminating 0
730 buflen = FFMIN(buflen - 1, maxlen);
731 for (i = 0; i < buflen; i++)
732 if (!(buf[i] = avio_r8(s)))
736 for (; i < maxlen; i++)
742 #define GET_STR16(type, read) \
743 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
747 while (ret + 1 < maxlen) {\
750 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
753 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
759 GET_STR16(le, avio_rl16)
760 GET_STR16(be, avio_rb16)
764 uint64_t avio_rb64(AVIOContext *s)
767 val = (uint64_t)avio_rb32(s) << 32;
768 val |= (uint64_t)avio_rb32(s);
772 uint64_t ffio_read_varlen(AVIOContext *bc){
778 val= (val<<7) + (tmp&127);
783 int url_fdopen(AVIOContext **s, URLContext *h)
786 int buffer_size, max_packet_size;
788 max_packet_size = url_get_max_packet_size(h);
789 if (max_packet_size) {
790 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
792 buffer_size = IO_BUFFER_SIZE;
794 buffer = av_malloc(buffer_size);
796 return AVERROR(ENOMEM);
798 *s = av_mallocz(sizeof(AVIOContext));
801 return AVERROR(ENOMEM);
804 if (ffio_init_context(*s, buffer, buffer_size,
805 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
806 url_read, url_write, url_seek) < 0) {
811 (*s)->is_streamed = h->is_streamed;
812 (*s)->max_packet_size = max_packet_size;
814 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
815 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
820 int ffio_set_buf_size(AVIOContext *s, int buf_size)
823 buffer = av_malloc(buf_size);
825 return AVERROR(ENOMEM);
829 s->buffer_size = buf_size;
831 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
835 #if FF_API_URL_RESETBUF
836 int url_resetbuf(AVIOContext *s, int flags)
838 static int url_resetbuf(AVIOContext *s, int flags)
841 #if FF_API_URL_RESETBUF
842 if (flags & URL_RDWR)
843 return AVERROR(EINVAL);
845 assert(flags == URL_WRONLY || flags == URL_RDONLY);
848 if (flags & URL_WRONLY) {
849 s->buf_end = s->buffer + s->buffer_size;
852 s->buf_end = s->buffer;
858 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
860 int64_t buffer_start;
862 int overlap, new_size, alloc_size;
865 return AVERROR(EINVAL);
867 buffer_size = s->buf_end - s->buffer;
869 /* the buffers must touch or overlap */
870 if ((buffer_start = s->pos - buffer_size) > buf_size)
871 return AVERROR(EINVAL);
873 overlap = buf_size - buffer_start;
874 new_size = buf_size + buffer_size - overlap;
876 alloc_size = FFMAX(s->buffer_size, new_size);
877 if (alloc_size > buf_size)
878 if (!(buf = av_realloc(buf, alloc_size)))
879 return AVERROR(ENOMEM);
881 if (new_size > buf_size) {
882 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
887 s->buf_ptr = s->buffer = buf;
888 s->buffer_size = alloc_size;
890 s->buf_end = s->buf_ptr + buf_size;
897 int avio_open(AVIOContext **s, const char *filename, int flags)
902 err = url_open(&h, filename, flags);
905 err = url_fdopen(s, h);
913 int avio_close(AVIOContext *s)
915 URLContext *h = s->opaque;
922 URLContext *url_fileno(AVIOContext *s)
927 int avio_printf(AVIOContext *s, const char *fmt, ...)
934 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
936 avio_write(s, buf, strlen(buf));
941 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
951 if (s->eof_reached || c == '\n')
953 if ((q - buf) < buf_size - 1)
962 int url_fget_max_packet_size(AVIOContext *s)
964 return s->max_packet_size;
968 int av_url_read_fpause(AVIOContext *s, int pause)
971 return AVERROR(ENOSYS);
972 return s->read_pause(s->opaque, pause);
975 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
976 int64_t timestamp, int flags)
978 URLContext *h = s->opaque;
981 return AVERROR(ENOSYS);
982 ret = s->read_seek(h, stream_index, timestamp, flags);
985 s->buf_ptr = s->buf_end; // Flush buffer
986 pos = s->seek(h, 0, SEEK_CUR);
989 else if (pos != AVERROR(ENOSYS))
995 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
996 * back to the server even if CONFIG_MUXERS is false. */
997 #if CONFIG_MUXERS || CONFIG_NETWORK
998 /* buffer handling */
999 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
1002 *s = av_mallocz(sizeof(AVIOContext));
1004 return AVERROR(ENOMEM);
1005 ret = ffio_init_context(*s, buf, buf_size,
1006 (flags & URL_WRONLY || flags & URL_RDWR),
1007 NULL, NULL, NULL, NULL);
1013 int url_close_buf(AVIOContext *s)
1015 put_flush_packet(s);
1016 return s->buf_ptr - s->buffer;
1019 /* output in a dynamic buffer */
1021 typedef struct DynBuffer {
1022 int pos, size, allocated_size;
1025 uint8_t io_buffer[1];
1028 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1030 DynBuffer *d = opaque;
1031 unsigned new_size, new_allocated_size;
1033 /* reallocate buffer if needed */
1034 new_size = d->pos + buf_size;
1035 new_allocated_size = d->allocated_size;
1036 if(new_size < d->pos || new_size > INT_MAX/2)
1038 while (new_size > new_allocated_size) {
1039 if (!new_allocated_size)
1040 new_allocated_size = new_size;
1042 new_allocated_size += new_allocated_size / 2 + 1;
1045 if (new_allocated_size > d->allocated_size) {
1046 d->buffer = av_realloc(d->buffer, new_allocated_size);
1047 if(d->buffer == NULL)
1048 return AVERROR(ENOMEM);
1049 d->allocated_size = new_allocated_size;
1051 memcpy(d->buffer + d->pos, buf, buf_size);
1053 if (d->pos > d->size)
1058 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1060 unsigned char buf1[4];
1063 /* packetized write: output the header */
1064 AV_WB32(buf1, buf_size);
1065 ret= dyn_buf_write(opaque, buf1, 4);
1070 return dyn_buf_write(opaque, buf, buf_size);
1073 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1075 DynBuffer *d = opaque;
1077 if (whence == SEEK_CUR)
1079 else if (whence == SEEK_END)
1081 if (offset < 0 || offset > 0x7fffffffLL)
1087 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1091 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1093 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1095 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1097 return AVERROR(ENOMEM);
1098 *s = av_mallocz(sizeof(AVIOContext));
1101 return AVERROR(ENOMEM);
1103 d->io_buffer_size = io_buffer_size;
1104 ret = ffio_init_context(*s, d->io_buffer, io_buffer_size,
1106 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1107 max_packet_size ? NULL : dyn_buf_seek);
1109 (*s)->max_packet_size = max_packet_size;
1117 int url_open_dyn_buf(AVIOContext **s)
1119 return url_open_dyn_buf_internal(s, 0);
1122 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1124 if (max_packet_size <= 0)
1126 return url_open_dyn_buf_internal(s, max_packet_size);
1129 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1131 DynBuffer *d = s->opaque;
1133 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1136 /* don't attempt to pad fixed-size packet buffers */
1137 if (!s->max_packet_size) {
1138 avio_write(s, padbuf, sizeof(padbuf));
1139 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1142 put_flush_packet(s);
1144 *pbuffer = d->buffer;
1148 return size - padding;
1150 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */