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"
29 #define IO_BUFFER_SIZE 32768
32 * Do seeks within this distance ahead of the current buffer by skipping
33 * data instead of calling the protocol seek function, for seekable
36 #define SHORT_SEEK_THRESHOLD 4096
38 static void fill_buffer(ByteIOContext *s);
39 #if !FF_API_URL_RESETBUF
40 static int url_resetbuf(ByteIOContext *s, int flags);
43 int init_put_byte(ByteIOContext *s,
44 unsigned char *buffer,
48 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
49 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
50 int64_t (*seek)(void *opaque, int64_t offset, int whence))
53 s->buffer_size = buffer_size;
56 url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
57 s->write_packet = write_packet;
58 s->read_packet = read_packet;
65 s->max_packet_size = 0;
66 s->update_checksum= NULL;
67 if(!read_packet && !write_flag){
69 s->buf_end = s->buffer + buffer_size;
76 ByteIOContext *av_alloc_put_byte(
77 unsigned char *buffer,
81 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
82 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
83 int64_t (*seek)(void *opaque, int64_t offset, int whence))
85 ByteIOContext *s = av_mallocz(sizeof(ByteIOContext));
86 init_put_byte(s, buffer, buffer_size, write_flag, opaque,
87 read_packet, write_packet, seek);
91 static void flush_buffer(ByteIOContext *s)
93 if (s->buf_ptr > s->buffer) {
94 if (s->write_packet && !s->error){
95 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
100 if(s->update_checksum){
101 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
102 s->checksum_ptr= s->buffer;
104 s->pos += s->buf_ptr - s->buffer;
106 s->buf_ptr = s->buffer;
109 void put_byte(ByteIOContext *s, int b)
112 if (s->buf_ptr >= s->buf_end)
116 void put_nbyte(ByteIOContext *s, int b, int count)
119 int len = FFMIN(s->buf_end - s->buf_ptr, count);
120 memset(s->buf_ptr, b, len);
123 if (s->buf_ptr >= s->buf_end)
130 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
133 int len = FFMIN(s->buf_end - s->buf_ptr, size);
134 memcpy(s->buf_ptr, buf, len);
137 if (s->buf_ptr >= s->buf_end)
145 void put_flush_packet(ByteIOContext *s)
151 int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
155 int force = whence & AVSEEK_FORCE;
156 whence &= ~AVSEEK_FORCE;
159 return AVERROR(EINVAL);
161 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
163 if (whence != SEEK_CUR && whence != SEEK_SET)
164 return AVERROR(EINVAL);
166 if (whence == SEEK_CUR) {
167 offset1 = pos + (s->buf_ptr - s->buffer);
172 offset1 = offset - pos;
173 if (!s->must_flush &&
174 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
175 /* can do the seek inside the buffer */
176 s->buf_ptr = s->buffer + offset1;
177 } else if ((s->is_streamed ||
178 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
179 !s->write_flag && offset1 >= 0 &&
180 (whence != SEEK_END || force)) {
181 while(s->pos < offset && !s->eof_reached)
185 s->buf_ptr = s->buf_end + offset - s->pos;
189 #if CONFIG_MUXERS || CONFIG_NETWORK
194 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
196 return AVERROR(EPIPE);
197 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
200 s->buf_end = s->buffer;
201 s->buf_ptr = s->buffer;
208 int url_fskip(ByteIOContext *s, int64_t offset)
210 int64_t ret = url_fseek(s, offset, SEEK_CUR);
211 return ret < 0 ? ret : 0;
214 int64_t url_ftell(ByteIOContext *s)
216 return url_fseek(s, 0, SEEK_CUR);
219 int64_t url_fsize(ByteIOContext *s)
224 return AVERROR(EINVAL);
227 return AVERROR(ENOSYS);
228 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
230 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
233 s->seek(s->opaque, s->pos, SEEK_SET);
238 int url_feof(ByteIOContext *s)
242 return s->eof_reached;
245 int url_ferror(ByteIOContext *s)
252 void put_le32(ByteIOContext *s, unsigned int val)
255 put_byte(s, val >> 8);
256 put_byte(s, val >> 16);
257 put_byte(s, val >> 24);
260 void put_be32(ByteIOContext *s, unsigned int val)
262 put_byte(s, val >> 24);
263 put_byte(s, val >> 16);
264 put_byte(s, val >> 8);
269 void put_strz(ByteIOContext *s, const char *str)
271 avio_put_str(s, str);
275 int avio_put_str(ByteIOContext *s, const char *str)
280 put_buffer(s, (const unsigned char *) str, len);
286 int avio_put_str16le(ByteIOContext *s, const char *str)
288 const uint8_t *q = str;
295 GET_UTF8(ch, *q++, break;)
296 PUT_UTF16(ch, tmp, put_le16(s, tmp);ret += 2;)
303 int ff_get_v_length(uint64_t val){
312 void ff_put_v(ByteIOContext *bc, uint64_t val){
313 int i= ff_get_v_length(val);
316 put_byte(bc, 128 | (val>>(7*i)));
318 put_byte(bc, val&127);
321 void put_le64(ByteIOContext *s, uint64_t val)
323 put_le32(s, (uint32_t)(val & 0xffffffff));
324 put_le32(s, (uint32_t)(val >> 32));
327 void put_be64(ByteIOContext *s, uint64_t val)
329 put_be32(s, (uint32_t)(val >> 32));
330 put_be32(s, (uint32_t)(val & 0xffffffff));
333 void put_le16(ByteIOContext *s, unsigned int val)
336 put_byte(s, val >> 8);
339 void put_be16(ByteIOContext *s, unsigned int val)
341 put_byte(s, val >> 8);
345 void put_le24(ByteIOContext *s, unsigned int val)
347 put_le16(s, val & 0xffff);
348 put_byte(s, val >> 16);
351 void put_be24(ByteIOContext *s, unsigned int val)
353 put_be16(s, val >> 8);
357 void put_tag(ByteIOContext *s, const char *tag)
366 static void fill_buffer(ByteIOContext *s)
368 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
369 int len= s->buffer_size - (dst - s->buffer);
370 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
372 /* no need to do anything if EOF already reached */
376 if(s->update_checksum && dst == s->buffer){
377 if(s->buf_end > s->checksum_ptr)
378 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
379 s->checksum_ptr= s->buffer;
382 /* make buffer smaller in case it ended up large after probing */
383 if (s->buffer_size > max_buffer_size) {
384 url_setbufsize(s, max_buffer_size);
386 s->checksum_ptr = dst = s->buffer;
387 len = s->buffer_size;
391 len = s->read_packet(s->opaque, dst, len);
395 /* do not modify buffer if EOF reached so that a seek back can
396 be done without rereading data */
403 s->buf_end = dst + len;
407 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
410 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
413 unsigned long get_checksum(ByteIOContext *s)
415 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
416 s->update_checksum= NULL;
420 void init_checksum(ByteIOContext *s,
421 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
422 unsigned long checksum)
424 s->update_checksum= update_checksum;
425 if(s->update_checksum){
426 s->checksum= checksum;
427 s->checksum_ptr= s->buf_ptr;
431 /* XXX: put an inline version */
432 int get_byte(ByteIOContext *s)
434 if (s->buf_ptr >= s->buf_end)
436 if (s->buf_ptr < s->buf_end)
437 return *s->buf_ptr++;
441 int url_fgetc(ByteIOContext *s)
443 if (s->buf_ptr >= s->buf_end)
445 if (s->buf_ptr < s->buf_end)
446 return *s->buf_ptr++;
450 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
456 len = s->buf_end - s->buf_ptr;
460 if(size > s->buffer_size && !s->update_checksum){
462 len = s->read_packet(s->opaque, buf, size);
464 /* do not modify buffer if EOF reached so that a seek back can
465 be done without rereading data */
474 s->buf_ptr = s->buffer;
475 s->buf_end = s->buffer/* + len*/;
479 len = s->buf_end - s->buf_ptr;
484 memcpy(buf, s->buf_ptr, len);
491 if (url_ferror(s)) return url_ferror(s);
492 if (url_feof(s)) return AVERROR_EOF;
497 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
504 len = s->buf_end - s->buf_ptr;
507 len = s->buf_end - s->buf_ptr;
511 memcpy(buf, s->buf_ptr, len);
514 if (url_ferror(s)) return url_ferror(s);
515 if (url_feof(s)) return AVERROR_EOF;
520 unsigned int get_le16(ByteIOContext *s)
524 val |= get_byte(s) << 8;
528 unsigned int get_le24(ByteIOContext *s)
532 val |= get_byte(s) << 16;
536 unsigned int get_le32(ByteIOContext *s)
540 val |= get_le16(s) << 16;
544 uint64_t get_le64(ByteIOContext *s)
547 val = (uint64_t)get_le32(s);
548 val |= (uint64_t)get_le32(s) << 32;
552 unsigned int get_be16(ByteIOContext *s)
555 val = get_byte(s) << 8;
560 unsigned int get_be24(ByteIOContext *s)
563 val = get_be16(s) << 8;
567 unsigned int get_be32(ByteIOContext *s)
570 val = get_be16(s) << 16;
575 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
580 while ((c = get_byte(s))) {
585 buf[i] = 0; /* Ensure null terminated, but may be truncated */
590 int ff_get_line(ByteIOContext *s, char *buf, int maxlen)
597 if (c && i < maxlen-1)
599 } while (c != '\n' && c);
605 #define GET_STR16(type, read) \
606 int avio_get_str16 ##type(ByteIOContext *pb, int maxlen, char *buf, int buflen)\
610 while (ret + 1 < maxlen) {\
613 GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
616 PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
622 GET_STR16(le, get_le16)
623 GET_STR16(be, get_be16)
627 uint64_t get_be64(ByteIOContext *s)
630 val = (uint64_t)get_be32(s) << 32;
631 val |= (uint64_t)get_be32(s);
635 uint64_t ff_get_v(ByteIOContext *bc){
641 val= (val<<7) + (tmp&127);
646 int url_fdopen(ByteIOContext **s, URLContext *h)
649 int buffer_size, max_packet_size;
651 max_packet_size = url_get_max_packet_size(h);
652 if (max_packet_size) {
653 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
655 buffer_size = IO_BUFFER_SIZE;
657 buffer = av_malloc(buffer_size);
659 return AVERROR(ENOMEM);
661 *s = av_mallocz(sizeof(ByteIOContext));
664 return AVERROR(ENOMEM);
667 if (init_put_byte(*s, buffer, buffer_size,
668 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
669 url_read, url_write, url_seek) < 0) {
674 (*s)->is_streamed = h->is_streamed;
675 (*s)->max_packet_size = max_packet_size;
677 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
678 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
683 int url_setbufsize(ByteIOContext *s, int buf_size)
686 buffer = av_malloc(buf_size);
688 return AVERROR(ENOMEM);
692 s->buffer_size = buf_size;
694 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
698 #if FF_API_URL_RESETBUF
699 int url_resetbuf(ByteIOContext *s, int flags)
701 static int url_resetbuf(ByteIOContext *s, int flags)
704 #if FF_API_URL_RESETBUF
705 if (flags & URL_RDWR)
706 return AVERROR(EINVAL);
708 assert(flags == URL_WRONLY || flags == URL_RDONLY);
711 if (flags & URL_WRONLY) {
712 s->buf_end = s->buffer + s->buffer_size;
715 s->buf_end = s->buffer;
721 int ff_rewind_with_probe_data(ByteIOContext *s, unsigned char *buf, int buf_size)
723 int64_t buffer_start;
725 int overlap, new_size, alloc_size;
728 return AVERROR(EINVAL);
730 buffer_size = s->buf_end - s->buffer;
732 /* the buffers must touch or overlap */
733 if ((buffer_start = s->pos - buffer_size) > buf_size)
734 return AVERROR(EINVAL);
736 overlap = buf_size - buffer_start;
737 new_size = buf_size + buffer_size - overlap;
739 alloc_size = FFMAX(s->buffer_size, new_size);
740 if (alloc_size > buf_size)
741 if (!(buf = av_realloc(buf, alloc_size)))
742 return AVERROR(ENOMEM);
744 if (new_size > buf_size) {
745 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
750 s->buf_ptr = s->buffer = buf;
751 s->buffer_size = alloc_size;
753 s->buf_end = s->buf_ptr + buf_size;
760 int url_fopen(ByteIOContext **s, const char *filename, int flags)
765 err = url_open(&h, filename, flags);
768 err = url_fdopen(s, h);
776 int url_fclose(ByteIOContext *s)
778 URLContext *h = s->opaque;
785 URLContext *url_fileno(ByteIOContext *s)
791 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
798 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
800 put_buffer(s, buf, strlen(buf));
803 #endif //CONFIG_MUXERS
805 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
815 if (c == EOF || c == '\n')
817 if ((q - buf) < buf_size - 1)
826 int url_fget_max_packet_size(ByteIOContext *s)
828 return s->max_packet_size;
831 int av_url_read_fpause(ByteIOContext *s, int pause)
834 return AVERROR(ENOSYS);
835 return s->read_pause(s->opaque, pause);
838 int64_t av_url_read_fseek(ByteIOContext *s, int stream_index,
839 int64_t timestamp, int flags)
841 URLContext *h = s->opaque;
844 return AVERROR(ENOSYS);
845 ret = s->read_seek(h, stream_index, timestamp, flags);
848 s->buf_ptr = s->buf_end; // Flush buffer
849 pos = s->seek(h, 0, SEEK_CUR);
852 else if (pos != AVERROR(ENOSYS))
858 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
859 * back to the server even if CONFIG_MUXERS is false. */
860 #if CONFIG_MUXERS || CONFIG_NETWORK
861 /* buffer handling */
862 int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
865 *s = av_mallocz(sizeof(ByteIOContext));
867 return AVERROR(ENOMEM);
868 ret = init_put_byte(*s, buf, buf_size,
869 (flags & URL_WRONLY || flags & URL_RDWR),
870 NULL, NULL, NULL, NULL);
876 int url_close_buf(ByteIOContext *s)
879 return s->buf_ptr - s->buffer;
882 /* output in a dynamic buffer */
884 typedef struct DynBuffer {
885 int pos, size, allocated_size;
888 uint8_t io_buffer[1];
891 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
893 DynBuffer *d = opaque;
894 unsigned new_size, new_allocated_size;
896 /* reallocate buffer if needed */
897 new_size = d->pos + buf_size;
898 new_allocated_size = d->allocated_size;
899 if(new_size < d->pos || new_size > INT_MAX/2)
901 while (new_size > new_allocated_size) {
902 if (!new_allocated_size)
903 new_allocated_size = new_size;
905 new_allocated_size += new_allocated_size / 2 + 1;
908 if (new_allocated_size > d->allocated_size) {
909 d->buffer = av_realloc(d->buffer, new_allocated_size);
910 if(d->buffer == NULL)
911 return AVERROR(ENOMEM);
912 d->allocated_size = new_allocated_size;
914 memcpy(d->buffer + d->pos, buf, buf_size);
916 if (d->pos > d->size)
921 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
923 unsigned char buf1[4];
926 /* packetized write: output the header */
927 AV_WB32(buf1, buf_size);
928 ret= dyn_buf_write(opaque, buf1, 4);
933 return dyn_buf_write(opaque, buf, buf_size);
936 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
938 DynBuffer *d = opaque;
940 if (whence == SEEK_CUR)
942 else if (whence == SEEK_END)
944 if (offset < 0 || offset > 0x7fffffffLL)
950 static int url_open_dyn_buf_internal(ByteIOContext **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 *s = av_mallocz(sizeof(ByteIOContext));
964 return AVERROR(ENOMEM);
966 d->io_buffer_size = io_buffer_size;
967 ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
969 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
970 max_packet_size ? NULL : dyn_buf_seek);
972 (*s)->max_packet_size = max_packet_size;
980 int url_open_dyn_buf(ByteIOContext **s)
982 return url_open_dyn_buf_internal(s, 0);
985 int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
987 if (max_packet_size <= 0)
989 return url_open_dyn_buf_internal(s, max_packet_size);
992 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
994 DynBuffer *d = s->opaque;
996 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
999 /* don't attempt to pad fixed-size packet buffers */
1000 if (!s->max_packet_size) {
1001 put_buffer(s, padbuf, sizeof(padbuf));
1002 padding = FF_INPUT_BUFFER_PADDING_SIZE;
1005 put_flush_packet(s);
1007 *pbuffer = d->buffer;
1011 return size - padding;
1013 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */