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 put_nbyte(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 url_fseek(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;
236 int url_fskip(AVIOContext *s, int64_t offset)
238 int64_t ret = url_fseek(s, offset, SEEK_CUR);
239 return ret < 0 ? ret : 0;
242 int64_t url_ftell(AVIOContext *s)
244 return url_fseek(s, 0, SEEK_CUR);
247 int64_t url_fsize(AVIOContext *s)
252 return AVERROR(EINVAL);
255 return AVERROR(ENOSYS);
256 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
258 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
261 s->seek(s->opaque, s->pos, SEEK_SET);
266 int url_feof(AVIOContext *s)
270 return s->eof_reached;
273 int url_ferror(AVIOContext *s)
280 void avio_wl32(AVIOContext *s, unsigned int val)
283 avio_w8(s, val >> 8);
284 avio_w8(s, val >> 16);
285 avio_w8(s, val >> 24);
288 void avio_wb32(AVIOContext *s, unsigned int val)
290 avio_w8(s, val >> 24);
291 avio_w8(s, val >> 16);
292 avio_w8(s, val >> 8);
297 void put_strz(AVIOContext *s, const char *str)
299 avio_put_str(s, str);
302 #define GET(name, type) \
303 type get_be ##name(AVIOContext *s) \
305 return avio_rb ##name(s);\
307 type get_le ##name(AVIOContext *s) \
309 return avio_rl ##name(s);\
312 GET(16, unsigned int)
313 GET(24, unsigned int)
314 GET(32, unsigned int)
319 #define PUT(name, type ) \
320 void put_le ##name(AVIOContext *s, type val)\
322 avio_wl ##name(s, val);\
324 void put_be ##name(AVIOContext *s, type val)\
326 avio_wb ##name(s, val);\
329 PUT(16, unsigned int)
330 PUT(24, unsigned int)
331 PUT(32, unsigned int)
335 int get_byte(AVIOContext *s)
339 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
341 return avio_read(s, buf, size);
343 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
345 return ffio_read_partial(s, buf, size);
347 void put_byte(AVIOContext *s, int val)
351 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
353 avio_write(s, buf, size);
357 int avio_put_str(AVIOContext *s, const char *str)
362 avio_write(s, (const unsigned char *) str, len);
368 int avio_put_str16le(AVIOContext *s, const char *str)
370 const uint8_t *q = str;
377 GET_UTF8(ch, *q++, break;)
378 PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
385 int ff_get_v_length(uint64_t val){
394 void ff_put_v(AVIOContext *bc, uint64_t val){
395 int i= ff_get_v_length(val);
398 avio_w8(bc, 128 | (val>>(7*i)));
400 avio_w8(bc, val&127);
403 void avio_wl64(AVIOContext *s, uint64_t val)
405 avio_wl32(s, (uint32_t)(val & 0xffffffff));
406 avio_wl32(s, (uint32_t)(val >> 32));
409 void avio_wb64(AVIOContext *s, uint64_t val)
411 avio_wb32(s, (uint32_t)(val >> 32));
412 avio_wb32(s, (uint32_t)(val & 0xffffffff));
415 void avio_wl16(AVIOContext *s, unsigned int val)
418 avio_w8(s, val >> 8);
421 void avio_wb16(AVIOContext *s, unsigned int val)
423 avio_w8(s, val >> 8);
427 void avio_wl24(AVIOContext *s, unsigned int val)
429 avio_wl16(s, val & 0xffff);
430 avio_w8(s, val >> 16);
433 void avio_wb24(AVIOContext *s, unsigned int val)
435 avio_wb16(s, val >> 8);
439 void put_tag(AVIOContext *s, const char *tag)
448 static void fill_buffer(AVIOContext *s)
450 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
451 int len= s->buffer_size - (dst - s->buffer);
452 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
454 /* no need to do anything if EOF already reached */
458 if(s->update_checksum && dst == s->buffer){
459 if(s->buf_end > s->checksum_ptr)
460 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
461 s->checksum_ptr= s->buffer;
464 /* make buffer smaller in case it ended up large after probing */
465 if (s->buffer_size > max_buffer_size) {
466 url_setbufsize(s, max_buffer_size);
468 s->checksum_ptr = dst = s->buffer;
469 len = s->buffer_size;
473 len = s->read_packet(s->opaque, dst, len);
477 /* do not modify buffer if EOF reached so that a seek back can
478 be done without rereading data */
485 s->buf_end = dst + len;
489 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
492 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
495 unsigned long get_checksum(AVIOContext *s)
497 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
498 s->update_checksum= NULL;
502 void init_checksum(AVIOContext *s,
503 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
504 unsigned long checksum)
506 s->update_checksum= update_checksum;
507 if(s->update_checksum){
508 s->checksum= checksum;
509 s->checksum_ptr= s->buf_ptr;
513 /* XXX: put an inline version */
514 int avio_r8(AVIOContext *s)
516 if (s->buf_ptr >= s->buf_end)
518 if (s->buf_ptr < s->buf_end)
519 return *s->buf_ptr++;
523 int url_fgetc(AVIOContext *s)
525 if (s->buf_ptr >= s->buf_end)
527 if (s->buf_ptr < s->buf_end)
528 return *s->buf_ptr++;
532 int avio_read(AVIOContext *s, unsigned char *buf, int size)
538 len = s->buf_end - s->buf_ptr;
542 if(size > s->buffer_size && !s->update_checksum){
544 len = s->read_packet(s->opaque, buf, size);
546 /* do not modify buffer if EOF reached so that a seek back can
547 be done without rereading data */
556 s->buf_ptr = s->buffer;
557 s->buf_end = s->buffer/* + len*/;
561 len = s->buf_end - s->buf_ptr;
566 memcpy(buf, s->buf_ptr, len);
573 if (url_ferror(s)) return url_ferror(s);
574 if (url_feof(s)) return AVERROR_EOF;
579 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
586 len = s->buf_end - s->buf_ptr;
589 len = s->buf_end - s->buf_ptr;
593 memcpy(buf, s->buf_ptr, len);
596 if (url_ferror(s)) return url_ferror(s);
597 if (url_feof(s)) return AVERROR_EOF;
602 unsigned int avio_rl16(AVIOContext *s)
606 val |= avio_r8(s) << 8;
610 unsigned int avio_rl24(AVIOContext *s)
614 val |= avio_r8(s) << 16;
618 unsigned int avio_rl32(AVIOContext *s)
622 val |= avio_rl16(s) << 16;
626 uint64_t avio_rl64(AVIOContext *s)
629 val = (uint64_t)avio_rl32(s);
630 val |= (uint64_t)avio_rl32(s) << 32;
634 unsigned int avio_rb16(AVIOContext *s)
637 val = avio_r8(s) << 8;
642 unsigned int avio_rb24(AVIOContext *s)
645 val = avio_rb16(s) << 8;
649 unsigned int avio_rb32(AVIOContext *s)
652 val = avio_rb16(s) << 16;
657 char *get_strz(AVIOContext *s, char *buf, int maxlen)
662 while ((c = avio_r8(s))) {
667 buf[i] = 0; /* Ensure null terminated, but may be truncated */
672 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
679 if (c && i < maxlen-1)
681 } while (c != '\n' && c);
687 #define GET_STR16(type, read) \
688 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
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 ff_get_v(AVIOContext *bc){
723 val= (val<<7) + (tmp&127);
728 int url_fdopen(AVIOContext **s, URLContext *h)
731 int buffer_size, max_packet_size;
733 max_packet_size = url_get_max_packet_size(h);
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 = av_mallocz(sizeof(AVIOContext));
746 return AVERROR(ENOMEM);
749 if (ffio_init_context(*s, buffer, buffer_size,
750 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
751 url_read, url_write, url_seek) < 0) {
756 (*s)->is_streamed = h->is_streamed;
757 (*s)->max_packet_size = max_packet_size;
759 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
760 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
765 int url_setbufsize(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 ? URL_WRONLY : URL_RDONLY);
780 #if FF_API_URL_RESETBUF
781 int url_resetbuf(AVIOContext *s, int flags)
783 static int url_resetbuf(AVIOContext *s, int flags)
786 #if FF_API_URL_RESETBUF
787 if (flags & URL_RDWR)
788 return AVERROR(EINVAL);
790 assert(flags == URL_WRONLY || flags == URL_RDONLY);
793 if (flags & URL_WRONLY) {
794 s->buf_end = s->buffer + s->buffer_size;
797 s->buf_end = s->buffer;
803 int ff_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
805 int64_t buffer_start;
807 int overlap, new_size, alloc_size;
810 return AVERROR(EINVAL);
812 buffer_size = s->buf_end - s->buffer;
814 /* the buffers must touch or overlap */
815 if ((buffer_start = s->pos - buffer_size) > buf_size)
816 return AVERROR(EINVAL);
818 overlap = buf_size - buffer_start;
819 new_size = buf_size + buffer_size - overlap;
821 alloc_size = FFMAX(s->buffer_size, new_size);
822 if (alloc_size > buf_size)
823 if (!(buf = av_realloc(buf, alloc_size)))
824 return AVERROR(ENOMEM);
826 if (new_size > buf_size) {
827 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
832 s->buf_ptr = s->buffer = buf;
833 s->buffer_size = alloc_size;
835 s->buf_end = s->buf_ptr + buf_size;
842 int url_fopen(AVIOContext **s, const char *filename, int flags)
847 err = url_open(&h, filename, flags);
850 err = url_fdopen(s, h);
858 int url_fclose(AVIOContext *s)
860 URLContext *h = s->opaque;
867 URLContext *url_fileno(AVIOContext *s)
873 int url_fprintf(AVIOContext *s, const char *fmt, ...)
880 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
882 avio_write(s, buf, strlen(buf));
885 #endif //CONFIG_MUXERS
887 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
897 if (c == EOF || c == '\n')
899 if ((q - buf) < buf_size - 1)
908 int url_fget_max_packet_size(AVIOContext *s)
910 return s->max_packet_size;
913 int av_url_read_fpause(AVIOContext *s, int pause)
916 return AVERROR(ENOSYS);
917 return s->read_pause(s->opaque, pause);
920 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
921 int64_t timestamp, int flags)
923 URLContext *h = s->opaque;
926 return AVERROR(ENOSYS);
927 ret = s->read_seek(h, stream_index, timestamp, flags);
930 s->buf_ptr = s->buf_end; // Flush buffer
931 pos = s->seek(h, 0, SEEK_CUR);
934 else if (pos != AVERROR(ENOSYS))
940 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
941 * back to the server even if CONFIG_MUXERS is false. */
942 #if CONFIG_MUXERS || CONFIG_NETWORK
943 /* buffer handling */
944 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
947 *s = av_mallocz(sizeof(AVIOContext));
949 return AVERROR(ENOMEM);
950 ret = ffio_init_context(*s, buf, buf_size,
951 (flags & URL_WRONLY || flags & URL_RDWR),
952 NULL, NULL, NULL, NULL);
958 int url_close_buf(AVIOContext *s)
961 return s->buf_ptr - s->buffer;
964 /* output in a dynamic buffer */
966 typedef struct DynBuffer {
967 int pos, size, allocated_size;
970 uint8_t io_buffer[1];
973 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
975 DynBuffer *d = opaque;
976 unsigned new_size, new_allocated_size;
978 /* reallocate buffer if needed */
979 new_size = d->pos + buf_size;
980 new_allocated_size = d->allocated_size;
981 if(new_size < d->pos || new_size > INT_MAX/2)
983 while (new_size > new_allocated_size) {
984 if (!new_allocated_size)
985 new_allocated_size = new_size;
987 new_allocated_size += new_allocated_size / 2 + 1;
990 if (new_allocated_size > d->allocated_size) {
991 d->buffer = av_realloc(d->buffer, new_allocated_size);
992 if(d->buffer == NULL)
993 return AVERROR(ENOMEM);
994 d->allocated_size = new_allocated_size;
996 memcpy(d->buffer + d->pos, buf, buf_size);
998 if (d->pos > d->size)
1003 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1005 unsigned char buf1[4];
1008 /* packetized write: output the header */
1009 AV_WB32(buf1, buf_size);
1010 ret= dyn_buf_write(opaque, buf1, 4);
1015 return dyn_buf_write(opaque, buf, buf_size);
1018 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1020 DynBuffer *d = opaque;
1022 if (whence == SEEK_CUR)
1024 else if (whence == SEEK_END)
1026 if (offset < 0 || offset > 0x7fffffffLL)
1032 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1036 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1038 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1040 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1042 return AVERROR(ENOMEM);
1043 *s = av_mallocz(sizeof(AVIOContext));
1046 return AVERROR(ENOMEM);
1048 d->io_buffer_size = io_buffer_size;
1049 ret = ffio_init_context(*s, d->io_buffer, io_buffer_size,
1051 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1052 max_packet_size ? NULL : dyn_buf_seek);
1054 (*s)->max_packet_size = max_packet_size;
1062 int url_open_dyn_buf(AVIOContext **s)
1064 return url_open_dyn_buf_internal(s, 0);
1067 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1069 if (max_packet_size <= 0)
1071 return url_open_dyn_buf_internal(s, max_packet_size);
1074 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1076 DynBuffer *d = s->opaque;
1078 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1081 /* don't attempt to pad fixed-size packet buffers */
1082 if (!s->max_packet_size) {
1083 avio_write(s, padbuf, sizeof(padbuf));
1084 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1087 put_flush_packet(s);
1089 *pbuffer = d->buffer;
1093 return size - padding;
1095 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */