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 LIBAVFORMAT_VERSION_MAJOR >= 53
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_buffer(ByteIOContext *s, const unsigned char *buf, int size)
119 int len = FFMIN(s->buf_end - s->buf_ptr, size);
120 memcpy(s->buf_ptr, buf, len);
123 if (s->buf_ptr >= s->buf_end)
131 void put_flush_packet(ByteIOContext *s)
137 int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
141 int force = whence & AVSEEK_FORCE;
142 whence &= ~AVSEEK_FORCE;
145 return AVERROR(EINVAL);
147 pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
149 if (whence != SEEK_CUR && whence != SEEK_SET)
150 return AVERROR(EINVAL);
152 if (whence == SEEK_CUR) {
153 offset1 = pos + (s->buf_ptr - s->buffer);
158 offset1 = offset - pos;
159 if (!s->must_flush &&
160 offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
161 /* can do the seek inside the buffer */
162 s->buf_ptr = s->buffer + offset1;
163 } else if ((s->is_streamed ||
164 offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
165 !s->write_flag && offset1 >= 0 &&
166 (whence != SEEK_END || force)) {
167 while(s->pos < offset && !s->eof_reached)
171 s->buf_ptr = s->buf_end + offset - s->pos;
175 #if CONFIG_MUXERS || CONFIG_NETWORK
180 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
182 return AVERROR(EPIPE);
183 if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
186 s->buf_end = s->buffer;
187 s->buf_ptr = s->buffer;
194 int url_fskip(ByteIOContext *s, int64_t offset)
196 int64_t ret = url_fseek(s, offset, SEEK_CUR);
197 return ret < 0 ? ret : 0;
200 int64_t url_ftell(ByteIOContext *s)
202 return url_fseek(s, 0, SEEK_CUR);
205 int64_t url_fsize(ByteIOContext *s)
210 return AVERROR(EINVAL);
213 return AVERROR(ENOSYS);
214 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
216 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
219 s->seek(s->opaque, s->pos, SEEK_SET);
224 int url_feof(ByteIOContext *s)
228 return s->eof_reached;
231 int url_ferror(ByteIOContext *s)
238 void put_le32(ByteIOContext *s, unsigned int val)
241 put_byte(s, val >> 8);
242 put_byte(s, val >> 16);
243 put_byte(s, val >> 24);
246 void put_be32(ByteIOContext *s, unsigned int val)
248 put_byte(s, val >> 24);
249 put_byte(s, val >> 16);
250 put_byte(s, val >> 8);
254 void put_strz(ByteIOContext *s, const char *str)
257 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
262 int ff_get_v_length(uint64_t val){
271 void ff_put_v(ByteIOContext *bc, uint64_t val){
272 int i= ff_get_v_length(val);
275 put_byte(bc, 128 | (val>>(7*i)));
277 put_byte(bc, val&127);
280 void put_le64(ByteIOContext *s, uint64_t val)
282 put_le32(s, (uint32_t)(val & 0xffffffff));
283 put_le32(s, (uint32_t)(val >> 32));
286 void put_be64(ByteIOContext *s, uint64_t val)
288 put_be32(s, (uint32_t)(val >> 32));
289 put_be32(s, (uint32_t)(val & 0xffffffff));
292 void put_le16(ByteIOContext *s, unsigned int val)
295 put_byte(s, val >> 8);
298 void put_be16(ByteIOContext *s, unsigned int val)
300 put_byte(s, val >> 8);
304 void put_le24(ByteIOContext *s, unsigned int val)
306 put_le16(s, val & 0xffff);
307 put_byte(s, val >> 16);
310 void put_be24(ByteIOContext *s, unsigned int val)
312 put_be16(s, val >> 8);
316 void put_tag(ByteIOContext *s, const char *tag)
325 static void fill_buffer(ByteIOContext *s)
327 uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
328 int len= s->buffer_size - (dst - s->buffer);
329 int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
331 assert(s->buf_ptr == s->buf_end);
333 /* no need to do anything if EOF already reached */
337 if(s->update_checksum && dst == s->buffer){
338 if(s->buf_end > s->checksum_ptr)
339 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
340 s->checksum_ptr= s->buffer;
343 /* make buffer smaller in case it ended up large after probing */
344 if (s->buffer_size > max_buffer_size) {
345 url_setbufsize(s, max_buffer_size);
347 s->checksum_ptr = dst = s->buffer;
348 len = s->buffer_size;
352 len = s->read_packet(s->opaque, dst, len);
356 /* do not modify buffer if EOF reached so that a seek back can
357 be done without rereading data */
364 s->buf_end = dst + len;
368 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
371 return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
374 unsigned long get_checksum(ByteIOContext *s)
376 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
377 s->update_checksum= NULL;
381 void init_checksum(ByteIOContext *s,
382 unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
383 unsigned long checksum)
385 s->update_checksum= update_checksum;
386 if(s->update_checksum){
387 s->checksum= checksum;
388 s->checksum_ptr= s->buf_ptr;
392 /* XXX: put an inline version */
393 int get_byte(ByteIOContext *s)
395 if (s->buf_ptr < s->buf_end) {
396 return *s->buf_ptr++;
399 if (s->buf_ptr < s->buf_end)
400 return *s->buf_ptr++;
406 int url_fgetc(ByteIOContext *s)
408 if (s->buf_ptr < s->buf_end) {
409 return *s->buf_ptr++;
412 if (s->buf_ptr < s->buf_end)
413 return *s->buf_ptr++;
419 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
425 len = s->buf_end - s->buf_ptr;
429 if(size > s->buffer_size && !s->update_checksum){
431 len = s->read_packet(s->opaque, buf, size);
433 /* do not modify buffer if EOF reached so that a seek back can
434 be done without rereading data */
443 s->buf_ptr = s->buffer;
444 s->buf_end = s->buffer/* + len*/;
448 len = s->buf_end - s->buf_ptr;
453 memcpy(buf, s->buf_ptr, len);
460 if (url_ferror(s)) return url_ferror(s);
461 if (url_feof(s)) return AVERROR_EOF;
466 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
473 len = s->buf_end - s->buf_ptr;
476 len = s->buf_end - s->buf_ptr;
480 memcpy(buf, s->buf_ptr, len);
483 if (url_ferror(s)) return url_ferror(s);
484 if (url_feof(s)) return AVERROR_EOF;
489 unsigned int get_le16(ByteIOContext *s)
493 val |= get_byte(s) << 8;
497 unsigned int get_le24(ByteIOContext *s)
501 val |= get_byte(s) << 16;
505 unsigned int get_le32(ByteIOContext *s)
509 val |= get_le16(s) << 16;
513 uint64_t get_le64(ByteIOContext *s)
516 val = (uint64_t)get_le32(s);
517 val |= (uint64_t)get_le32(s) << 32;
521 unsigned int get_be16(ByteIOContext *s)
524 val = get_byte(s) << 8;
529 unsigned int get_be24(ByteIOContext *s)
532 val = get_be16(s) << 8;
536 unsigned int get_be32(ByteIOContext *s)
539 val = get_be16(s) << 16;
544 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
549 while ((c = get_byte(s))) {
554 buf[i] = 0; /* Ensure null terminated, but may be truncated */
559 uint64_t get_be64(ByteIOContext *s)
562 val = (uint64_t)get_be32(s) << 32;
563 val |= (uint64_t)get_be32(s);
567 uint64_t ff_get_v(ByteIOContext *bc){
573 val= (val<<7) + (tmp&127);
578 int url_fdopen(ByteIOContext **s, URLContext *h)
581 int buffer_size, max_packet_size;
583 max_packet_size = url_get_max_packet_size(h);
584 if (max_packet_size) {
585 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
587 buffer_size = IO_BUFFER_SIZE;
589 buffer = av_malloc(buffer_size);
591 return AVERROR(ENOMEM);
593 *s = av_mallocz(sizeof(ByteIOContext));
596 return AVERROR(ENOMEM);
599 if (init_put_byte(*s, buffer, buffer_size,
600 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
601 url_read, url_write, url_seek) < 0) {
606 (*s)->is_streamed = h->is_streamed;
607 (*s)->max_packet_size = max_packet_size;
609 (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
610 (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
615 int url_setbufsize(ByteIOContext *s, int buf_size)
618 buffer = av_malloc(buf_size);
620 return AVERROR(ENOMEM);
624 s->buffer_size = buf_size;
626 url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
630 #if LIBAVFORMAT_VERSION_MAJOR < 53
631 int url_resetbuf(ByteIOContext *s, int flags)
633 static int url_resetbuf(ByteIOContext *s, int flags)
636 #if LIBAVFORMAT_VERSION_MAJOR < 53
637 if (flags & URL_RDWR)
638 return AVERROR(EINVAL);
640 assert(flags == URL_WRONLY || flags == URL_RDONLY);
643 if (flags & URL_WRONLY) {
644 s->buf_end = s->buffer + s->buffer_size;
647 s->buf_end = s->buffer;
653 int ff_rewind_with_probe_data(ByteIOContext *s, unsigned char *buf, int buf_size)
655 int64_t buffer_start;
657 int overlap, new_size;
660 return AVERROR(EINVAL);
662 buffer_size = s->buf_end - s->buffer;
664 /* the buffers must touch or overlap */
665 if ((buffer_start = s->pos - buffer_size) > buf_size)
666 return AVERROR(EINVAL);
668 overlap = buf_size - buffer_start;
669 new_size = buf_size + buffer_size - overlap;
671 if (new_size > buf_size) {
672 if (!(buf = av_realloc(buf, new_size)))
673 return AVERROR(ENOMEM);
675 memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
680 s->buf_ptr = s->buffer = buf;
681 s->pos = s->buffer_size = buf_size;
682 s->buf_end = s->buf_ptr + buf_size;
689 int url_fopen(ByteIOContext **s, const char *filename, int flags)
694 err = url_open(&h, filename, flags);
697 err = url_fdopen(s, h);
705 int url_fclose(ByteIOContext *s)
707 URLContext *h = s->opaque;
714 URLContext *url_fileno(ByteIOContext *s)
720 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
727 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
729 put_buffer(s, buf, strlen(buf));
732 #endif //CONFIG_MUXERS
734 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
744 if (c == EOF || c == '\n')
746 if ((q - buf) < buf_size - 1)
755 int url_fget_max_packet_size(ByteIOContext *s)
757 return s->max_packet_size;
760 int av_url_read_fpause(ByteIOContext *s, int pause)
763 return AVERROR(ENOSYS);
764 return s->read_pause(s->opaque, pause);
767 int64_t av_url_read_fseek(ByteIOContext *s, int stream_index,
768 int64_t timestamp, int flags)
770 URLContext *h = s->opaque;
773 return AVERROR(ENOSYS);
774 ret = s->read_seek(h, stream_index, timestamp, flags);
777 s->buf_ptr = s->buf_end; // Flush buffer
778 pos = s->seek(h, 0, SEEK_CUR);
781 else if (pos != AVERROR(ENOSYS))
787 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
788 * back to the server even if CONFIG_MUXERS is false. */
789 #if CONFIG_MUXERS || CONFIG_NETWORK
790 /* buffer handling */
791 int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
794 *s = av_mallocz(sizeof(ByteIOContext));
796 return AVERROR(ENOMEM);
797 ret = init_put_byte(*s, buf, buf_size,
798 (flags & URL_WRONLY || flags & URL_RDWR),
799 NULL, NULL, NULL, NULL);
805 int url_close_buf(ByteIOContext *s)
808 return s->buf_ptr - s->buffer;
811 /* output in a dynamic buffer */
813 typedef struct DynBuffer {
814 int pos, size, allocated_size;
817 uint8_t io_buffer[1];
820 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
822 DynBuffer *d = opaque;
823 unsigned new_size, new_allocated_size;
825 /* reallocate buffer if needed */
826 new_size = d->pos + buf_size;
827 new_allocated_size = d->allocated_size;
828 if(new_size < d->pos || new_size > INT_MAX/2)
830 while (new_size > new_allocated_size) {
831 if (!new_allocated_size)
832 new_allocated_size = new_size;
834 new_allocated_size += new_allocated_size / 2 + 1;
837 if (new_allocated_size > d->allocated_size) {
838 d->buffer = av_realloc(d->buffer, new_allocated_size);
839 if(d->buffer == NULL)
840 return AVERROR(ENOMEM);
841 d->allocated_size = new_allocated_size;
843 memcpy(d->buffer + d->pos, buf, buf_size);
845 if (d->pos > d->size)
850 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
852 unsigned char buf1[4];
855 /* packetized write: output the header */
856 AV_WB32(buf1, buf_size);
857 ret= dyn_buf_write(opaque, buf1, 4);
862 return dyn_buf_write(opaque, buf, buf_size);
865 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
867 DynBuffer *d = opaque;
869 if (whence == SEEK_CUR)
871 else if (whence == SEEK_END)
873 if (offset < 0 || offset > 0x7fffffffLL)
879 static int url_open_dyn_buf_internal(ByteIOContext **s, int max_packet_size)
883 unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
885 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
887 d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
889 return AVERROR(ENOMEM);
890 *s = av_mallocz(sizeof(ByteIOContext));
893 return AVERROR(ENOMEM);
895 d->io_buffer_size = io_buffer_size;
896 ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
898 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
899 max_packet_size ? NULL : dyn_buf_seek);
901 (*s)->max_packet_size = max_packet_size;
909 int url_open_dyn_buf(ByteIOContext **s)
911 return url_open_dyn_buf_internal(s, 0);
914 int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
916 if (max_packet_size <= 0)
918 return url_open_dyn_buf_internal(s, max_packet_size);
921 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
923 DynBuffer *d = s->opaque;
925 static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
928 /* don't attempt to pad fixed-size packet buffers */
929 if (!s->max_packet_size) {
930 put_buffer(s, padbuf, sizeof(padbuf));
931 padding = FF_INPUT_BUFFER_PADDING_SIZE;
936 *pbuffer = d->buffer;
940 return size - padding;
942 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */