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 url_fsize(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);
268 int url_feof(AVIOContext *s)
272 return s->eof_reached;
275 int url_ferror(AVIOContext *s)
282 void avio_wl32(AVIOContext *s, unsigned int val)
285 avio_w8(s, val >> 8);
286 avio_w8(s, val >> 16);
287 avio_w8(s, val >> 24);
290 void avio_wb32(AVIOContext *s, unsigned int val)
292 avio_w8(s, val >> 24);
293 avio_w8(s, val >> 16);
294 avio_w8(s, val >> 8);
299 void put_strz(AVIOContext *s, const char *str)
301 avio_put_str(s, str);
304 #define GET(name, type) \
305 type get_be ##name(AVIOContext *s) \
307 return avio_rb ##name(s);\
309 type get_le ##name(AVIOContext *s) \
311 return avio_rl ##name(s);\
314 GET(16, unsigned int)
315 GET(24, unsigned int)
316 GET(32, unsigned int)
321 #define PUT(name, type ) \
322 void put_le ##name(AVIOContext *s, type val)\
324 avio_wl ##name(s, val);\
326 void put_be ##name(AVIOContext *s, type val)\
328 avio_wb ##name(s, val);\
331 PUT(16, unsigned int)
332 PUT(24, unsigned int)
333 PUT(32, unsigned int)
337 int get_byte(AVIOContext *s)
341 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
343 return avio_read(s, buf, size);
345 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
347 return ffio_read_partial(s, buf, size);
349 void put_byte(AVIOContext *s, int val)
353 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
355 avio_write(s, buf, size);
357 void put_nbyte(AVIOContext *s, int b, int count)
359 ffio_fill(s, b, count);
362 int url_fopen(AVIOContext **s, const char *filename, int flags)
364 return avio_open(s, filename, flags);
366 int url_fclose(AVIOContext *s)
368 return avio_close(s);
370 int64_t url_fseek(AVIOContext *s, int64_t offset, int whence)
372 return avio_seek(s, offset, whence);
376 int avio_put_str(AVIOContext *s, const char *str)
381 avio_write(s, (const unsigned char *) str, len);
387 int avio_put_str16le(AVIOContext *s, const char *str)
389 const uint8_t *q = str;
396 GET_UTF8(ch, *q++, break;)
397 PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
404 int ff_get_v_length(uint64_t val){
413 void ff_put_v(AVIOContext *bc, uint64_t val){
414 int i= ff_get_v_length(val);
417 avio_w8(bc, 128 | (val>>(7*i)));
419 avio_w8(bc, val&127);
422 void avio_wl64(AVIOContext *s, uint64_t val)
424 avio_wl32(s, (uint32_t)(val & 0xffffffff));
425 avio_wl32(s, (uint32_t)(val >> 32));
428 void avio_wb64(AVIOContext *s, uint64_t val)
430 avio_wb32(s, (uint32_t)(val >> 32));
431 avio_wb32(s, (uint32_t)(val & 0xffffffff));
434 void avio_wl16(AVIOContext *s, unsigned int val)
437 avio_w8(s, val >> 8);
440 void avio_wb16(AVIOContext *s, unsigned int val)
442 avio_w8(s, val >> 8);
446 void avio_wl24(AVIOContext *s, unsigned int val)
448 avio_wl16(s, val & 0xffff);
449 avio_w8(s, val >> 16);
452 void avio_wb24(AVIOContext *s, unsigned int val)
454 avio_wb16(s, val >> 8);
459 void put_tag(AVIOContext *s, const char *tag)
469 static void fill_buffer(AVIOContext *s)
471 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_end : s->buffer;
472 int len= s->buffer_size - (dst - s->buffer);
473 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
475 /* no need to do anything if EOF already reached */
479 if(s->update_checksum && dst == s->buffer){
480 if(s->buf_end > s->checksum_ptr)
481 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
482 s->checksum_ptr= s->buffer;
485 /* make buffer smaller in case it ended up large after probing */
486 if (s->buffer_size > max_buffer_size) {
487 url_setbufsize(s, max_buffer_size);
489 s->checksum_ptr = dst = s->buffer;
490 len = s->buffer_size;
494 len = s->read_packet(s->opaque, dst, len);
498 /* do not modify buffer if EOF reached so that a seek back can
499 be done without rereading data */
506 s->buf_end = dst + len;
510 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
513 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
516 unsigned long get_checksum(AVIOContext *s)
518 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
519 s->update_checksum= NULL;
523 void init_checksum(AVIOContext *s,
524 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
525 unsigned long checksum)
527 s->update_checksum= update_checksum;
528 if(s->update_checksum){
529 s->checksum= checksum;
530 s->checksum_ptr= s->buf_ptr;
534 /* XXX: put an inline version */
535 int avio_r8(AVIOContext *s)
537 if (s->buf_ptr >= s->buf_end)
539 if (s->buf_ptr < s->buf_end)
540 return *s->buf_ptr++;
544 int url_fgetc(AVIOContext *s)
546 if (s->buf_ptr >= s->buf_end)
548 if (s->buf_ptr < s->buf_end)
549 return *s->buf_ptr++;
553 int avio_read(AVIOContext *s, unsigned char *buf, int size)
559 len = s->buf_end - s->buf_ptr;
563 if(size > s->buffer_size && !s->update_checksum){
565 len = s->read_packet(s->opaque, buf, size);
567 /* do not modify buffer if EOF reached so that a seek back can
568 be done without rereading data */
577 s->buf_ptr = s->buffer;
578 s->buf_end = s->buffer/* + len*/;
582 len = s->buf_end - s->buf_ptr;
587 memcpy(buf, s->buf_ptr, len);
594 if (url_ferror(s)) return url_ferror(s);
595 if (url_feof(s)) return AVERROR_EOF;
600 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
607 len = s->buf_end - s->buf_ptr;
610 len = s->buf_end - s->buf_ptr;
614 memcpy(buf, s->buf_ptr, len);
617 if (url_ferror(s)) return url_ferror(s);
618 if (url_feof(s)) return AVERROR_EOF;
623 unsigned int avio_rl16(AVIOContext *s)
627 val |= avio_r8(s) << 8;
631 unsigned int avio_rl24(AVIOContext *s)
635 val |= avio_r8(s) << 16;
639 unsigned int avio_rl32(AVIOContext *s)
643 val |= avio_rl16(s) << 16;
647 uint64_t avio_rl64(AVIOContext *s)
650 val = (uint64_t)avio_rl32(s);
651 val |= (uint64_t)avio_rl32(s) << 32;
655 unsigned int avio_rb16(AVIOContext *s)
658 val = avio_r8(s) << 8;
663 unsigned int avio_rb24(AVIOContext *s)
666 val = avio_rb16(s) << 8;
670 unsigned int avio_rb32(AVIOContext *s)
673 val = avio_rb16(s) << 16;
679 char *get_strz(AVIOContext *s, char *buf, int maxlen)
681 avio_get_str(s, INT_MAX, buf, maxlen);
686 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
693 if (c && i < maxlen-1)
695 } while (c != '\n' && c);
701 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
705 // reserve 1 byte for terminating 0
706 buflen = FFMIN(buflen - 1, maxlen);
707 for (i = 0; i < buflen; i++)
708 if (!(buf[i] = avio_r8(s)))
712 for (; i < maxlen; i++)
718 #define GET_STR16(type, read) \
719 int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
723 while (ret + 1 < maxlen) {\
726 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
729 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
735 GET_STR16(le, avio_rl16)
736 GET_STR16(be, avio_rb16)
740 uint64_t avio_rb64(AVIOContext *s)
743 val = (uint64_t)avio_rb32(s) << 32;
744 val |= (uint64_t)avio_rb32(s);
748 uint64_t ff_get_v(AVIOContext *bc){
754 val= (val<<7) + (tmp&127);
759 int url_fdopen(AVIOContext **s, URLContext *h)
762 int buffer_size, max_packet_size;
764 max_packet_size = url_get_max_packet_size(h);
765 if (max_packet_size) {
766 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
768 buffer_size = IO_BUFFER_SIZE;
770 buffer = av_malloc(buffer_size);
772 return AVERROR(ENOMEM);
774 *s = av_mallocz(sizeof(AVIOContext));
777 return AVERROR(ENOMEM);
780 if (ffio_init_context(*s, buffer, buffer_size,
781 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
782 url_read, url_write, url_seek) < 0) {
787 (*s)->is_streamed = h->is_streamed;
788 (*s)->max_packet_size = max_packet_size;
790 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
791 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
796 int url_setbufsize(AVIOContext *s, int buf_size)
799 buffer = av_malloc(buf_size);
801 return AVERROR(ENOMEM);
805 s->buffer_size = buf_size;
807 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
811 #if FF_API_URL_RESETBUF
812 int url_resetbuf(AVIOContext *s, int flags)
814 static int url_resetbuf(AVIOContext *s, int flags)
817 #if FF_API_URL_RESETBUF
818 if (flags & URL_RDWR)
819 return AVERROR(EINVAL);
821 assert(flags == URL_WRONLY || flags == URL_RDONLY);
824 if (flags & URL_WRONLY) {
825 s->buf_end = s->buffer + s->buffer_size;
828 s->buf_end = s->buffer;
834 int ff_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
836 int64_t buffer_start;
838 int overlap, new_size, alloc_size;
841 return AVERROR(EINVAL);
843 buffer_size = s->buf_end - s->buffer;
845 /* the buffers must touch or overlap */
846 if ((buffer_start = s->pos - buffer_size) > buf_size)
847 return AVERROR(EINVAL);
849 overlap = buf_size - buffer_start;
850 new_size = buf_size + buffer_size - overlap;
852 alloc_size = FFMAX(s->buffer_size, new_size);
853 if (alloc_size > buf_size)
854 if (!(buf = av_realloc(buf, alloc_size)))
855 return AVERROR(ENOMEM);
857 if (new_size > buf_size) {
858 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
863 s->buf_ptr = s->buffer = buf;
864 s->buffer_size = alloc_size;
866 s->buf_end = s->buf_ptr + buf_size;
873 int avio_open(AVIOContext **s, const char *filename, int flags)
878 err = url_open(&h, filename, flags);
881 err = url_fdopen(s, h);
889 int avio_close(AVIOContext *s)
891 URLContext *h = s->opaque;
898 URLContext *url_fileno(AVIOContext *s)
904 int url_fprintf(AVIOContext *s, const char *fmt, ...)
911 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
913 avio_write(s, buf, strlen(buf));
916 #endif //CONFIG_MUXERS
919 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
929 if (c == EOF || c == '\n')
931 if ((q - buf) < buf_size - 1)
941 int url_fget_max_packet_size(AVIOContext *s)
943 return s->max_packet_size;
946 int av_url_read_fpause(AVIOContext *s, int pause)
949 return AVERROR(ENOSYS);
950 return s->read_pause(s->opaque, pause);
953 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
954 int64_t timestamp, int flags)
956 URLContext *h = s->opaque;
959 return AVERROR(ENOSYS);
960 ret = s->read_seek(h, stream_index, timestamp, flags);
963 s->buf_ptr = s->buf_end; // Flush buffer
964 pos = s->seek(h, 0, SEEK_CUR);
967 else if (pos != AVERROR(ENOSYS))
973 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
974 * back to the server even if CONFIG_MUXERS is false. */
975 #if CONFIG_MUXERS || CONFIG_NETWORK
976 /* buffer handling */
977 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
980 *s = av_mallocz(sizeof(AVIOContext));
982 return AVERROR(ENOMEM);
983 ret = ffio_init_context(*s, buf, buf_size,
984 (flags & URL_WRONLY || flags & URL_RDWR),
985 NULL, NULL, NULL, NULL);
991 int url_close_buf(AVIOContext *s)
994 return s->buf_ptr - s->buffer;
997 /* output in a dynamic buffer */
999 typedef struct DynBuffer {
1000 int pos, size, allocated_size;
1003 uint8_t io_buffer[1];
1006 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
1008 DynBuffer *d = opaque;
1009 unsigned new_size, new_allocated_size;
1011 /* reallocate buffer if needed */
1012 new_size = d->pos + buf_size;
1013 new_allocated_size = d->allocated_size;
1014 if(new_size < d->pos || new_size > INT_MAX/2)
1016 while (new_size > new_allocated_size) {
1017 if (!new_allocated_size)
1018 new_allocated_size = new_size;
1020 new_allocated_size += new_allocated_size / 2 + 1;
1023 if (new_allocated_size > d->allocated_size) {
1024 d->buffer = av_realloc(d->buffer, new_allocated_size);
1025 if(d->buffer == NULL)
1026 return AVERROR(ENOMEM);
1027 d->allocated_size = new_allocated_size;
1029 memcpy(d->buffer + d->pos, buf, buf_size);
1031 if (d->pos > d->size)
1036 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
1038 unsigned char buf1[4];
1041 /* packetized write: output the header */
1042 AV_WB32(buf1, buf_size);
1043 ret= dyn_buf_write(opaque, buf1, 4);
1048 return dyn_buf_write(opaque, buf, buf_size);
1051 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
1053 DynBuffer *d = opaque;
1055 if (whence == SEEK_CUR)
1057 else if (whence == SEEK_END)
1059 if (offset < 0 || offset > 0x7fffffffLL)
1065 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
1069 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
1071 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
1073 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
1075 return AVERROR(ENOMEM);
1076 *s = av_mallocz(sizeof(AVIOContext));
1079 return AVERROR(ENOMEM);
1081 d->io_buffer_size = io_buffer_size;
1082 ret = ffio_init_context(*s, d->io_buffer, io_buffer_size,
1084 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
1085 max_packet_size ? NULL : dyn_buf_seek);
1087 (*s)->max_packet_size = max_packet_size;
1095 int url_open_dyn_buf(AVIOContext **s)
1097 return url_open_dyn_buf_internal(s, 0);
1100 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
1102 if (max_packet_size <= 0)
1104 return url_open_dyn_buf_internal(s, max_packet_size);
1107 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
1109 DynBuffer *d = s->opaque;
1111 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
1114 /* don't attempt to pad fixed-size packet buffers */
1115 if (!s->max_packet_size) {
1116 avio_write(s, padbuf, sizeof(padbuf));
1117 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1120 put_flush_packet(s);
1122 *pbuffer = d->buffer;
1126 return size - padding;
1128 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */