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;
236 int64_t avio_skip(AVIOContext *s, int64_t offset)
238 return avio_seek(s, offset, SEEK_CUR);
242 int url_fskip(AVIOContext *s, int64_t offset)
244 int64_t ret = avio_seek(s, offset, SEEK_CUR);
245 return ret < 0 ? ret : 0;
248 int64_t url_ftell(AVIOContext *s)
250 return avio_seek(s, 0, SEEK_CUR);
254 int64_t avio_size(AVIOContext *s)
259 return AVERROR(EINVAL);
262 return AVERROR(ENOSYS);
263 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
265 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
268 s->seek(s->opaque, s->pos, SEEK_SET);
273 int url_feof(AVIOContext *s)
281 return s->eof_reached;
284 int url_ferror(AVIOContext *s)
291 void avio_wl32(AVIOContext *s, unsigned int val)
294 avio_w8(s, val >> 8);
295 avio_w8(s, val >> 16);
296 avio_w8(s, val >> 24);
299 void avio_wb32(AVIOContext *s, unsigned int val)
301 avio_w8(s, val >> 24);
302 avio_w8(s, val >> 16);
303 avio_w8(s, val >> 8);
308 void put_strz(AVIOContext *s, const char *str)
310 avio_put_str(s, str);
313 #define GET(name, type) \
314 type get_be ##name(AVIOContext *s) \
316 return avio_rb ##name(s);\
318 type get_le ##name(AVIOContext *s) \
320 return avio_rl ##name(s);\
323 GET(16, unsigned int)
324 GET(24, unsigned int)
325 GET(32, unsigned int)
330 #define PUT(name, type ) \
331 void put_le ##name(AVIOContext *s, type val)\
333 avio_wl ##name(s, val);\
335 void put_be ##name(AVIOContext *s, type val)\
337 avio_wb ##name(s, val);\
340 PUT(16, unsigned int)
341 PUT(24, unsigned int)
342 PUT(32, unsigned int)
346 int get_byte(AVIOContext *s)
350 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
352 return avio_read(s, buf, size);
354 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
356 return ffio_read_partial(s, buf, size);
358 void put_byte(AVIOContext *s, int val)
362 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
364 avio_write(s, buf, size);
366 void put_nbyte(AVIOContext *s, int b, int count)
368 ffio_fill(s, b, count);
371 int url_fopen(AVIOContext **s, const char *filename, int flags)
373 return avio_open(s, filename, flags);
375 int url_fclose(AVIOContext *s)
377 return avio_close(s);
379 int64_t url_fseek(AVIOContext *s, int64_t offset, int whence)
381 return avio_seek(s, offset, whence);
383 int64_t url_fsize(AVIOContext *s)
389 int avio_put_str(AVIOContext *s, const char *str)
394 avio_write(s, (const unsigned char *) str, len);
400 int avio_put_str16le(AVIOContext *s, const char *str)
402 const uint8_t *q = str;
409 GET_UTF8(ch, *q++, break;)
410 PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
417 int ff_get_v_length(uint64_t val){
426 void ff_put_v(AVIOContext *bc, uint64_t val){
427 int i= ff_get_v_length(val);
430 avio_w8(bc, 128 | (val>>(7*i)));
432 avio_w8(bc, val&127);
435 void avio_wl64(AVIOContext *s, uint64_t val)
437 avio_wl32(s, (uint32_t)(val & 0xffffffff));
438 avio_wl32(s, (uint32_t)(val >> 32));
441 void avio_wb64(AVIOContext *s, uint64_t val)
443 avio_wb32(s, (uint32_t)(val >> 32));
444 avio_wb32(s, (uint32_t)(val & 0xffffffff));
447 void avio_wl16(AVIOContext *s, unsigned int val)
450 avio_w8(s, val >> 8);
453 void avio_wb16(AVIOContext *s, unsigned int val)
455 avio_w8(s, val >> 8);
459 void avio_wl24(AVIOContext *s, unsigned int val)
461 avio_wl16(s, val & 0xffff);
462 avio_w8(s, val >> 16);
465 void avio_wb24(AVIOContext *s, unsigned int val)
467 avio_wb16(s, val >> 8);
472 void put_tag(AVIOContext *s, const char *tag)
482 static void fill_buffer(AVIOContext *s)
484 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_end : s->buffer;
485 int len= s->buffer_size - (dst - s->buffer);
486 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
488 /* no need to do anything if EOF already reached */
492 if(s->update_checksum && dst == s->buffer){
493 if(s->buf_end > s->checksum_ptr)
494 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
495 s->checksum_ptr= s->buffer;
498 /* make buffer smaller in case it ended up large after probing */
499 if (s->buffer_size > max_buffer_size) {
500 url_setbufsize(s, max_buffer_size);
502 s->checksum_ptr = dst = s->buffer;
503 len = s->buffer_size;
507 len = s->read_packet(s->opaque, dst, len);
511 /* do not modify buffer if EOF reached so that a seek back can
512 be done without rereading data */
519 s->buf_end = dst + len;
523 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
526 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
529 unsigned long get_checksum(AVIOContext *s)
531 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
532 s->update_checksum= NULL;
536 void init_checksum(AVIOContext *s,
537 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
538 unsigned long checksum)
540 s->update_checksum= update_checksum;
541 if(s->update_checksum){
542 s->checksum= checksum;
543 s->checksum_ptr= s->buf_ptr;
547 /* XXX: put an inline version */
548 int avio_r8(AVIOContext *s)
550 if (s->buf_ptr >= s->buf_end)
552 if (s->buf_ptr < s->buf_end)
553 return *s->buf_ptr++;
558 int url_fgetc(AVIOContext *s)
560 if (s->buf_ptr >= s->buf_end)
562 if (s->buf_ptr < s->buf_end)
563 return *s->buf_ptr++;
568 int avio_read(AVIOContext *s, unsigned char *buf, int size)
574 len = s->buf_end - s->buf_ptr;
578 if(size > s->buffer_size && !s->update_checksum){
580 len = s->read_packet(s->opaque, buf, size);
582 /* do not modify buffer if EOF reached so that a seek back can
583 be done without rereading data */
592 s->buf_ptr = s->buffer;
593 s->buf_end = s->buffer/* + len*/;
597 len = s->buf_end - s->buf_ptr;
602 memcpy(buf, s->buf_ptr, len);
609 if (url_ferror(s)) return url_ferror(s);
610 if (url_feof(s)) return AVERROR_EOF;
615 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
622 len = s->buf_end - s->buf_ptr;
625 len = s->buf_end - s->buf_ptr;
629 memcpy(buf, s->buf_ptr, len);
632 if (url_ferror(s)) return url_ferror(s);
633 if (url_feof(s)) return AVERROR_EOF;
638 unsigned int avio_rl16(AVIOContext *s)
642 val |= avio_r8(s) << 8;
646 unsigned int avio_rl24(AVIOContext *s)
650 val |= avio_r8(s) << 16;
654 unsigned int avio_rl32(AVIOContext *s)
658 val |= avio_rl16(s) << 16;
662 uint64_t avio_rl64(AVIOContext *s)
665 val = (uint64_t)avio_rl32(s);
666 val |= (uint64_t)avio_rl32(s) << 32;
670 unsigned int avio_rb16(AVIOContext *s)
673 val = avio_r8(s) << 8;
678 unsigned int avio_rb24(AVIOContext *s)
681 val = avio_rb16(s) << 8;
685 unsigned int avio_rb32(AVIOContext *s)
688 val = avio_rb16(s) << 16;
694 char *get_strz(AVIOContext *s, char *buf, int maxlen)
696 avio_get_str(s, INT_MAX, buf, maxlen);
701 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
708 if (c && i < maxlen-1)
710 } while (c != '\n' && c);
716 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
720 // reserve 1 byte for terminating 0
721 buflen = FFMIN(buflen - 1, maxlen);
722 for (i = 0; i < buflen; i++)
723 if (!(buf[i] = avio_r8(s)))
727 for (; i < maxlen; i++)
733 #define GET_STR16(type, read) \
734 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
738 while (ret + 1 < maxlen) {\
741 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
744 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
750 GET_STR16(le, avio_rl16)
751 GET_STR16(be, avio_rb16)
755 uint64_t avio_rb64(AVIOContext *s)
758 val = (uint64_t)avio_rb32(s) << 32;
759 val |= (uint64_t)avio_rb32(s);
763 uint64_t ff_get_v(AVIOContext *bc){
769 val= (val<<7) + (tmp&127);
774 int url_fdopen(AVIOContext **s, URLContext *h)
777 int buffer_size, max_packet_size;
779 max_packet_size = url_get_max_packet_size(h);
780 if (max_packet_size) {
781 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
783 buffer_size = IO_BUFFER_SIZE;
785 buffer = av_malloc(buffer_size);
787 return AVERROR(ENOMEM);
789 *s = av_mallocz(sizeof(AVIOContext));
792 return AVERROR(ENOMEM);
795 if (ffio_init_context(*s, buffer, buffer_size,
796 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
797 url_read, url_write, url_seek) < 0) {
802 (*s)->is_streamed = h->is_streamed;
803 (*s)->max_packet_size = max_packet_size;
805 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
806 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
811 int url_setbufsize(AVIOContext *s, int buf_size)
814 buffer = av_malloc(buf_size);
816 return AVERROR(ENOMEM);
820 s->buffer_size = buf_size;
822 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
826 #if FF_API_URL_RESETBUF
827 int url_resetbuf(AVIOContext *s, int flags)
829 static int url_resetbuf(AVIOContext *s, int flags)
832 #if FF_API_URL_RESETBUF
833 if (flags & URL_RDWR)
834 return AVERROR(EINVAL);
836 assert(flags == URL_WRONLY || flags == URL_RDONLY);
839 if (flags & URL_WRONLY) {
840 s->buf_end = s->buffer + s->buffer_size;
843 s->buf_end = s->buffer;
849 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
851 int64_t buffer_start;
853 int overlap, new_size, alloc_size;
856 return AVERROR(EINVAL);
858 buffer_size = s->buf_end - s->buffer;
860 /* the buffers must touch or overlap */
861 if ((buffer_start = s->pos - buffer_size) > buf_size)
862 return AVERROR(EINVAL);
864 overlap = buf_size - buffer_start;
865 new_size = buf_size + buffer_size - overlap;
867 alloc_size = FFMAX(s->buffer_size, new_size);
868 if (alloc_size > buf_size)
869 if (!(buf = av_realloc(buf, alloc_size)))
870 return AVERROR(ENOMEM);
872 if (new_size > buf_size) {
873 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
878 s->buf_ptr = s->buffer = buf;
879 s->buffer_size = alloc_size;
881 s->buf_end = s->buf_ptr + buf_size;
888 int avio_open(AVIOContext **s, const char *filename, int flags)
893 err = url_open(&h, filename, flags);
896 err = url_fdopen(s, h);
904 int avio_close(AVIOContext *s)
906 URLContext *h = s->opaque;
913 URLContext *url_fileno(AVIOContext *s)
919 int url_fprintf(AVIOContext *s, const char *fmt, ...)
926 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
928 avio_write(s, buf, strlen(buf));
931 #endif //CONFIG_MUXERS
934 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
944 if (url_feof(s) || c == '\n')
946 if ((q - buf) < buf_size - 1)
955 int url_fget_max_packet_size(AVIOContext *s)
957 return s->max_packet_size;
961 int av_url_read_fpause(AVIOContext *s, int pause)
964 return AVERROR(ENOSYS);
965 return s->read_pause(s->opaque, pause);
968 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
969 int64_t timestamp, int flags)
971 URLContext *h = s->opaque;
974 return AVERROR(ENOSYS);
975 ret = s->read_seek(h, stream_index, timestamp, flags);
978 s->buf_ptr = s->buf_end; // Flush buffer
979 pos = s->seek(h, 0, SEEK_CUR);
982 else if (pos != AVERROR(ENOSYS))
988 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
989 * back to the server even if CONFIG_MUXERS is false. */
990 #if CONFIG_MUXERS || CONFIG_NETWORK
991 /* buffer handling */
992 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
995 *s = av_mallocz(sizeof(AVIOContext));
997 return AVERROR(ENOMEM);
998 ret = ffio_init_context(*s, buf, buf_size,
999 (flags & URL_WRONLY || flags & URL_RDWR),
1000 NULL, NULL, NULL, NULL);
1006 int url_close_buf(AVIOContext *s)
1008 put_flush_packet(s);
1009 return s->buf_ptr - s->buffer;
1012 /* output in a dynamic buffer */
1014 typedef struct DynBuffer {
1015 int pos, size, allocated_size;
1018 uint8_t io_buffer[1];
1021 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1023 DynBuffer *d = opaque;
1024 unsigned new_size, new_allocated_size;
1026 /* reallocate buffer if needed */
1027 new_size = d->pos + buf_size;
1028 new_allocated_size = d->allocated_size;
1029 if(new_size < d->pos || new_size > INT_MAX/2)
1031 while (new_size > new_allocated_size) {
1032 if (!new_allocated_size)
1033 new_allocated_size = new_size;
1035 new_allocated_size += new_allocated_size / 2 + 1;
1038 if (new_allocated_size > d->allocated_size) {
1039 d->buffer = av_realloc(d->buffer, new_allocated_size);
1040 if(d->buffer == NULL)
1041 return AVERROR(ENOMEM);
1042 d->allocated_size = new_allocated_size;
1044 memcpy(d->buffer + d->pos, buf, buf_size);
1046 if (d->pos > d->size)
1051 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1053 unsigned char buf1[4];
1056 /* packetized write: output the header */
1057 AV_WB32(buf1, buf_size);
1058 ret= dyn_buf_write(opaque, buf1, 4);
1063 return dyn_buf_write(opaque, buf, buf_size);
1066 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1068 DynBuffer *d = opaque;
1070 if (whence == SEEK_CUR)
1072 else if (whence == SEEK_END)
1074 if (offset < 0 || offset > 0x7fffffffLL)
1080 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1084 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1086 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1088 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1090 return AVERROR(ENOMEM);
1091 *s = av_mallocz(sizeof(AVIOContext));
1094 return AVERROR(ENOMEM);
1096 d->io_buffer_size = io_buffer_size;
1097 ret = ffio_init_context(*s, d->io_buffer, io_buffer_size,
1099 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1100 max_packet_size ? NULL : dyn_buf_seek);
1102 (*s)->max_packet_size = max_packet_size;
1110 int url_open_dyn_buf(AVIOContext **s)
1112 return url_open_dyn_buf_internal(s, 0);
1115 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1117 if (max_packet_size <= 0)
1119 return url_open_dyn_buf_internal(s, max_packet_size);
1122 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1124 DynBuffer *d = s->opaque;
1126 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1129 /* don't attempt to pad fixed-size packet buffers */
1130 if (!s->max_packet_size) {
1131 avio_write(s, padbuf, sizeof(padbuf));
1132 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1135 put_flush_packet(s);
1137 *pbuffer = d->buffer;
1141 return size - padding;
1143 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */