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
25 #define IO_BUFFER_SIZE 32768
27 static void fill_buffer(ByteIOContext *s);
29 int init_put_byte(ByteIOContext *s,
30 unsigned char *buffer,
34 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
35 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
36 offset_t (*seek)(void *opaque, offset_t offset, int whence))
39 s->buffer_size = buffer_size;
41 s->write_flag = write_flag;
45 s->buf_end = buffer + buffer_size;
47 s->write_packet = write_packet;
48 s->read_packet = read_packet;
55 s->max_packet_size = 0;
56 s->update_checksum= NULL;
57 if(!read_packet && !write_flag){
59 s->buf_end = s->buffer + buffer_size;
64 static void flush_buffer(ByteIOContext *s)
66 if (s->buf_ptr > s->buffer) {
67 if (s->write_packet && !s->error){
68 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
73 if(s->update_checksum){
74 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
75 s->checksum_ptr= s->buffer;
77 s->pos += s->buf_ptr - s->buffer;
79 s->buf_ptr = s->buffer;
82 void put_byte(ByteIOContext *s, int b)
85 if (s->buf_ptr >= s->buf_end)
89 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
94 len = (s->buf_end - s->buf_ptr);
97 memcpy(s->buf_ptr, buf, len);
100 if (s->buf_ptr >= s->buf_end)
108 void put_flush_packet(ByteIOContext *s)
114 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
117 offset_t pos= s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
119 if (whence != SEEK_CUR && whence != SEEK_SET)
120 return AVERROR(EINVAL);
122 if (whence == SEEK_CUR) {
123 offset1 = pos + (s->buf_ptr - s->buffer);
128 offset1 = offset - pos;
129 if (!s->must_flush &&
130 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
131 /* can do the seek inside the buffer */
132 s->buf_ptr = s->buffer + offset1;
133 } else if(s->is_streamed && !s->write_flag &&
134 offset1 >= 0 && offset1 < (s->buf_end - s->buffer) + (1<<16)){
135 while(s->pos < offset && !s->eof_reached)
137 s->buf_ptr = s->buf_end + offset - s->pos;
139 offset_t res = AVERROR(EPIPE);
141 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
146 #endif /* defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK) */
148 s->buf_end = s->buffer;
150 s->buf_ptr = s->buffer;
151 if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
159 void url_fskip(ByteIOContext *s, offset_t offset)
161 url_fseek(s, offset, SEEK_CUR);
164 offset_t url_ftell(ByteIOContext *s)
166 return url_fseek(s, 0, SEEK_CUR);
169 offset_t url_fsize(ByteIOContext *s)
174 return AVERROR(EPIPE);
175 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
177 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
180 s->seek(s->opaque, s->pos, SEEK_SET);
185 int url_feof(ByteIOContext *s)
187 return s->eof_reached;
190 int url_ferror(ByteIOContext *s)
195 void put_le32(ByteIOContext *s, unsigned int val)
198 put_byte(s, val >> 8);
199 put_byte(s, val >> 16);
200 put_byte(s, val >> 24);
203 void put_be32(ByteIOContext *s, unsigned int val)
205 put_byte(s, val >> 24);
206 put_byte(s, val >> 16);
207 put_byte(s, val >> 8);
211 void put_strz(ByteIOContext *s, const char *str)
214 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
219 void put_le64(ByteIOContext *s, uint64_t val)
221 put_le32(s, (uint32_t)(val & 0xffffffff));
222 put_le32(s, (uint32_t)(val >> 32));
225 void put_be64(ByteIOContext *s, uint64_t val)
227 put_be32(s, (uint32_t)(val >> 32));
228 put_be32(s, (uint32_t)(val & 0xffffffff));
231 void put_le16(ByteIOContext *s, unsigned int val)
234 put_byte(s, val >> 8);
237 void put_be16(ByteIOContext *s, unsigned int val)
239 put_byte(s, val >> 8);
243 void put_le24(ByteIOContext *s, unsigned int val)
245 put_le16(s, val & 0xffff);
246 put_byte(s, val >> 16);
249 void put_be24(ByteIOContext *s, unsigned int val)
251 put_be16(s, val >> 8);
255 void put_tag(ByteIOContext *s, const char *tag)
264 static void fill_buffer(ByteIOContext *s)
268 /* no need to do anything if EOF already reached */
272 if(s->update_checksum){
273 if(s->buf_end > s->checksum_ptr)
274 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
275 s->checksum_ptr= s->buffer;
278 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
280 /* do not modify buffer if EOF reached so that a seek back can
281 be done without rereading data */
287 s->buf_ptr = s->buffer;
288 s->buf_end = s->buffer + len;
292 unsigned long get_checksum(ByteIOContext *s){
293 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
294 s->update_checksum= NULL;
298 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
299 s->update_checksum= update_checksum;
300 if(s->update_checksum){
301 s->checksum= checksum;
302 s->checksum_ptr= s->buf_ptr;
306 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
308 /* XXX: put an inline version */
309 int get_byte(ByteIOContext *s)
311 if (s->buf_ptr < s->buf_end) {
312 return *s->buf_ptr++;
315 if (s->buf_ptr < s->buf_end)
316 return *s->buf_ptr++;
322 /* NOTE: return URL_EOF (-1) if EOF */
323 int url_fgetc(ByteIOContext *s)
325 if (s->buf_ptr < s->buf_end) {
326 return *s->buf_ptr++;
329 if (s->buf_ptr < s->buf_end)
330 return *s->buf_ptr++;
336 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
342 len = s->buf_end - s->buf_ptr;
346 if(size > s->buffer_size && !s->update_checksum){
347 len = s->read_packet(s->opaque, buf, size);
349 /* do not modify buffer if EOF reached so that a seek back can
350 be done without rereading data */
359 s->buf_ptr = s->buffer;
360 s->buf_end = s->buffer/* + len*/;
364 len = s->buf_end - s->buf_ptr;
369 memcpy(buf, s->buf_ptr, len);
378 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
385 len = s->buf_end - s->buf_ptr;
388 len = s->buf_end - s->buf_ptr;
392 memcpy(buf, s->buf_ptr, len);
397 unsigned int get_le16(ByteIOContext *s)
401 val |= get_byte(s) << 8;
405 unsigned int get_le24(ByteIOContext *s)
409 val |= get_byte(s) << 16;
413 unsigned int get_le32(ByteIOContext *s)
417 val |= get_le16(s) << 16;
421 uint64_t get_le64(ByteIOContext *s)
424 val = (uint64_t)get_le32(s);
425 val |= (uint64_t)get_le32(s) << 32;
429 unsigned int get_be16(ByteIOContext *s)
432 val = get_byte(s) << 8;
437 unsigned int get_be24(ByteIOContext *s)
440 val = get_be16(s) << 8;
444 unsigned int get_be32(ByteIOContext *s)
447 val = get_be16(s) << 16;
452 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
457 while ((c = get_byte(s))) {
462 buf[i] = 0; /* Ensure null terminated, but may be truncated */
467 uint64_t get_be64(ByteIOContext *s)
470 val = (uint64_t)get_be32(s) << 32;
471 val |= (uint64_t)get_be32(s);
475 /* link with avio functions */
478 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
480 URLContext *h = opaque;
481 return url_write(h, buf, buf_size);
484 #define url_write_packet NULL
485 #endif //CONFIG_MUXERS
487 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
489 URLContext *h = opaque;
490 return url_read(h, buf, buf_size);
493 static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
495 URLContext *h = opaque;
496 return url_seek(h, offset, whence);
500 int url_fdopen(ByteIOContext *s, URLContext *h)
503 int buffer_size, max_packet_size;
506 max_packet_size = url_get_max_packet_size(h);
507 if (max_packet_size) {
508 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
510 buffer_size = IO_BUFFER_SIZE;
512 buffer = av_malloc(buffer_size);
514 return AVERROR(ENOMEM);
516 if (init_put_byte(s, buffer, buffer_size,
517 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
518 url_read_packet, url_write_packet, url_seek_packet) < 0) {
522 s->is_streamed = h->is_streamed;
523 s->max_packet_size = max_packet_size;
527 /* XXX: must be called before any I/O */
528 int url_setbufsize(ByteIOContext *s, int buf_size)
531 buffer = av_malloc(buf_size);
533 return AVERROR(ENOMEM);
537 s->buffer_size = buf_size;
542 s->buf_end = buffer + buf_size;
546 /* NOTE: when opened as read/write, the buffers are only used for
548 int url_fopen(ByteIOContext *s, const char *filename, int flags)
553 err = url_open(&h, filename, flags);
556 err = url_fdopen(s, h);
564 int url_fclose(ByteIOContext *s)
566 URLContext *h = s->opaque;
569 memset(s, 0, sizeof(ByteIOContext));
573 URLContext *url_fileno(ByteIOContext *s)
579 /* XXX: currently size is limited */
580 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
587 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
589 put_buffer(s, buf, strlen(buf));
592 #endif //CONFIG_MUXERS
594 /* note: unlike fgets, the EOL character is not returned and a whole
595 line is parsed. return NULL if first char read was EOF */
596 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
606 if (c == EOF || c == '\n')
608 if ((q - buf) < buf_size - 1)
618 * Return the maximum packet size associated to packetized buffered file
619 * handle. If the file is not packetized (stream like http or file on
620 * disk), then 0 is returned.
622 * @param h buffered file handle
623 * @return maximum packet size in bytes
625 int url_fget_max_packet_size(ByteIOContext *s)
627 return s->max_packet_size;
630 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
631 * back to the server even if CONFIG_MUXERS is not set. */
632 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
633 /* buffer handling */
634 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
636 return init_put_byte(s, buf, buf_size,
637 (flags & URL_WRONLY || flags & URL_RDWR),
638 NULL, NULL, NULL, NULL);
641 /* return the written or read size */
642 int url_close_buf(ByteIOContext *s)
645 return s->buf_ptr - s->buffer;
648 /* output in a dynamic buffer */
650 typedef struct DynBuffer {
651 int pos, size, allocated_size;
654 uint8_t io_buffer[1];
657 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
659 DynBuffer *d = opaque;
660 int new_size, new_allocated_size;
662 /* reallocate buffer if needed */
663 new_size = d->pos + buf_size;
664 new_allocated_size = d->allocated_size;
665 if(new_size < d->pos || new_size > INT_MAX/2)
667 while (new_size > new_allocated_size) {
668 if (!new_allocated_size)
669 new_allocated_size = new_size;
671 new_allocated_size += new_allocated_size / 2 + 1;
674 if (new_allocated_size > d->allocated_size) {
675 d->buffer = av_realloc(d->buffer, new_allocated_size);
676 if(d->buffer == NULL)
678 d->allocated_size = new_allocated_size;
680 memcpy(d->buffer + d->pos, buf, buf_size);
682 if (d->pos > d->size)
687 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
689 unsigned char buf1[4];
692 /* packetized write: output the header */
693 buf1[0] = (buf_size >> 24);
694 buf1[1] = (buf_size >> 16);
695 buf1[2] = (buf_size >> 8);
696 buf1[3] = (buf_size);
697 ret= dyn_buf_write(opaque, buf1, 4);
702 return dyn_buf_write(opaque, buf, buf_size);
705 static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
707 DynBuffer *d = opaque;
709 if (whence == SEEK_CUR)
711 else if (whence == SEEK_END)
713 if (offset < 0 || offset > 0x7fffffffLL)
719 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
722 int io_buffer_size, ret;
725 io_buffer_size = max_packet_size;
727 io_buffer_size = 1024;
729 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
731 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
734 d->io_buffer_size = io_buffer_size;
738 d->allocated_size = 0;
739 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
741 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
742 max_packet_size ? NULL : dyn_buf_seek);
744 s->max_packet_size = max_packet_size;
750 * Open a write only memory stream.
752 * @param s new IO context
753 * @return zero if no error.
755 int url_open_dyn_buf(ByteIOContext *s)
757 return url_open_dyn_buf_internal(s, 0);
761 * Open a write only packetized memory stream with a maximum packet
762 * size of 'max_packet_size'. The stream is stored in a memory buffer
763 * with a big endian 4 byte header giving the packet size in bytes.
765 * @param s new IO context
766 * @param max_packet_size maximum packet size (must be > 0)
767 * @return zero if no error.
769 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
771 if (max_packet_size <= 0)
773 return url_open_dyn_buf_internal(s, max_packet_size);
777 * Return the written size and a pointer to the buffer. The buffer
778 * must be freed with av_free().
779 * @param s IO context
780 * @param pointer to a byte buffer
781 * @return the length of the byte buffer
783 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
785 DynBuffer *d = s->opaque;
790 *pbuffer = d->buffer;
795 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */