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)
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 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
144 #endif /* defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK) */
146 s->buf_end = s->buffer;
148 s->buf_ptr = s->buffer;
149 if (!s->seek || s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
157 void url_fskip(ByteIOContext *s, offset_t offset)
159 url_fseek(s, offset, SEEK_CUR);
162 offset_t url_ftell(ByteIOContext *s)
164 return url_fseek(s, 0, SEEK_CUR);
167 offset_t url_fsize(ByteIOContext *s)
173 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
175 size = s->seek(s->opaque, -1, SEEK_END) + 1;
176 s->seek(s->opaque, s->pos, SEEK_SET);
181 int url_feof(ByteIOContext *s)
183 return s->eof_reached;
186 int url_ferror(ByteIOContext *s)
191 void put_le32(ByteIOContext *s, unsigned int val)
194 put_byte(s, val >> 8);
195 put_byte(s, val >> 16);
196 put_byte(s, val >> 24);
199 void put_be32(ByteIOContext *s, unsigned int val)
201 put_byte(s, val >> 24);
202 put_byte(s, val >> 16);
203 put_byte(s, val >> 8);
207 void put_strz(ByteIOContext *s, const char *str)
210 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
215 void put_le64(ByteIOContext *s, uint64_t val)
217 put_le32(s, (uint32_t)(val & 0xffffffff));
218 put_le32(s, (uint32_t)(val >> 32));
221 void put_be64(ByteIOContext *s, uint64_t val)
223 put_be32(s, (uint32_t)(val >> 32));
224 put_be32(s, (uint32_t)(val & 0xffffffff));
227 void put_le16(ByteIOContext *s, unsigned int val)
230 put_byte(s, val >> 8);
233 void put_be16(ByteIOContext *s, unsigned int val)
235 put_byte(s, val >> 8);
239 void put_le24(ByteIOContext *s, unsigned int val)
241 put_le16(s, val & 0xffff);
242 put_byte(s, val >> 16);
245 void put_be24(ByteIOContext *s, unsigned int val)
247 put_be16(s, val >> 8);
251 void put_tag(ByteIOContext *s, const char *tag)
260 static void fill_buffer(ByteIOContext *s)
264 /* no need to do anything if EOF already reached */
268 if(s->update_checksum){
269 if(s->buf_end > s->checksum_ptr)
270 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
271 s->checksum_ptr= s->buffer;
274 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
276 /* do not modify buffer if EOF reached so that a seek back can
277 be done without rereading data */
283 s->buf_ptr = s->buffer;
284 s->buf_end = s->buffer + len;
288 unsigned long get_checksum(ByteIOContext *s){
289 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
290 s->update_checksum= NULL;
294 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
295 s->update_checksum= update_checksum;
296 if(s->update_checksum){
297 s->checksum= checksum;
298 s->checksum_ptr= s->buf_ptr;
302 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
304 /* XXX: put an inline version */
305 int get_byte(ByteIOContext *s)
307 if (s->buf_ptr < s->buf_end) {
308 return *s->buf_ptr++;
311 if (s->buf_ptr < s->buf_end)
312 return *s->buf_ptr++;
318 /* NOTE: return URL_EOF (-1) if EOF */
319 int url_fgetc(ByteIOContext *s)
321 if (s->buf_ptr < s->buf_end) {
322 return *s->buf_ptr++;
325 if (s->buf_ptr < s->buf_end)
326 return *s->buf_ptr++;
332 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
338 len = s->buf_end - s->buf_ptr;
342 if(size > s->buffer_size && !s->update_checksum){
343 len = s->read_packet(s->opaque, buf, size);
345 /* do not modify buffer if EOF reached so that a seek back can
346 be done without rereading data */
355 s->buf_ptr = s->buffer;
356 s->buf_end = s->buffer/* + len*/;
360 len = s->buf_end - s->buf_ptr;
365 memcpy(buf, s->buf_ptr, len);
374 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
381 len = s->buf_end - s->buf_ptr;
384 len = s->buf_end - s->buf_ptr;
388 memcpy(buf, s->buf_ptr, len);
393 unsigned int get_le16(ByteIOContext *s)
397 val |= get_byte(s) << 8;
401 unsigned int get_le24(ByteIOContext *s)
405 val |= get_byte(s) << 16;
409 unsigned int get_le32(ByteIOContext *s)
413 val |= get_le16(s) << 16;
417 uint64_t get_le64(ByteIOContext *s)
420 val = (uint64_t)get_le32(s);
421 val |= (uint64_t)get_le32(s) << 32;
425 unsigned int get_be16(ByteIOContext *s)
428 val = get_byte(s) << 8;
433 unsigned int get_be24(ByteIOContext *s)
436 val = get_be16(s) << 8;
440 unsigned int get_be32(ByteIOContext *s)
443 val = get_be16(s) << 16;
448 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
453 while ((c = get_byte(s))) {
458 buf[i] = 0; /* Ensure null terminated, but may be truncated */
463 uint64_t get_be64(ByteIOContext *s)
466 val = (uint64_t)get_be32(s) << 32;
467 val |= (uint64_t)get_be32(s);
471 /* link with avio functions */
474 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
476 URLContext *h = opaque;
477 return url_write(h, buf, buf_size);
480 #define url_write_packet NULL
481 #endif //CONFIG_MUXERS
483 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
485 URLContext *h = opaque;
486 return url_read(h, buf, buf_size);
489 static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
491 URLContext *h = opaque;
492 return url_seek(h, offset, whence);
496 int url_fdopen(ByteIOContext *s, URLContext *h)
499 int buffer_size, max_packet_size;
502 max_packet_size = url_get_max_packet_size(h);
503 if (max_packet_size) {
504 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
506 buffer_size = IO_BUFFER_SIZE;
508 buffer = av_malloc(buffer_size);
512 if (init_put_byte(s, buffer, buffer_size,
513 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
514 url_read_packet, url_write_packet, url_seek_packet) < 0) {
518 s->is_streamed = h->is_streamed;
519 s->max_packet_size = max_packet_size;
523 /* XXX: must be called before any I/O */
524 int url_setbufsize(ByteIOContext *s, int buf_size)
527 buffer = av_malloc(buf_size);
533 s->buffer_size = buf_size;
538 s->buf_end = buffer + buf_size;
542 /* NOTE: when opened as read/write, the buffers are only used for
544 int url_fopen(ByteIOContext *s, const char *filename, int flags)
549 err = url_open(&h, filename, flags);
552 err = url_fdopen(s, h);
560 int url_fclose(ByteIOContext *s)
562 URLContext *h = s->opaque;
565 memset(s, 0, sizeof(ByteIOContext));
569 URLContext *url_fileno(ByteIOContext *s)
575 /* XXX: currently size is limited */
576 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
583 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
585 put_buffer(s, buf, strlen(buf));
588 #endif //CONFIG_MUXERS
590 /* note: unlike fgets, the EOL character is not returned and a whole
591 line is parsed. return NULL if first char read was EOF */
592 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
602 if (c == EOF || c == '\n')
604 if ((q - buf) < buf_size - 1)
614 * Return the maximum packet size associated to packetized buffered file
615 * handle. If the file is not packetized (stream like http or file on
616 * disk), then 0 is returned.
618 * @param h buffered file handle
619 * @return maximum packet size in bytes
621 int url_fget_max_packet_size(ByteIOContext *s)
623 return s->max_packet_size;
626 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
627 * back to the server even if CONFIG_MUXERS is not set. */
628 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
629 /* buffer handling */
630 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
632 return init_put_byte(s, buf, buf_size,
633 (flags & URL_WRONLY || flags & URL_RDWR),
634 NULL, NULL, NULL, NULL);
637 /* return the written or read size */
638 int url_close_buf(ByteIOContext *s)
641 return s->buf_ptr - s->buffer;
644 /* output in a dynamic buffer */
646 typedef struct DynBuffer {
647 int pos, size, allocated_size;
650 uint8_t io_buffer[1];
653 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
655 DynBuffer *d = opaque;
656 int new_size, new_allocated_size;
658 /* reallocate buffer if needed */
659 new_size = d->pos + buf_size;
660 new_allocated_size = d->allocated_size;
661 if(new_size < d->pos || new_size > INT_MAX/2)
663 while (new_size > new_allocated_size) {
664 if (!new_allocated_size)
665 new_allocated_size = new_size;
667 new_allocated_size += new_allocated_size / 2 + 1;
670 if (new_allocated_size > d->allocated_size) {
671 d->buffer = av_realloc(d->buffer, new_allocated_size);
672 if(d->buffer == NULL)
674 d->allocated_size = new_allocated_size;
676 memcpy(d->buffer + d->pos, buf, buf_size);
678 if (d->pos > d->size)
683 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
685 unsigned char buf1[4];
688 /* packetized write: output the header */
689 buf1[0] = (buf_size >> 24);
690 buf1[1] = (buf_size >> 16);
691 buf1[2] = (buf_size >> 8);
692 buf1[3] = (buf_size);
693 ret= dyn_buf_write(opaque, buf1, 4);
698 return dyn_buf_write(opaque, buf, buf_size);
701 static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
703 DynBuffer *d = opaque;
705 if (whence == SEEK_CUR)
707 else if (whence == SEEK_END)
709 if (offset < 0 || offset > 0x7fffffffLL)
715 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
718 int io_buffer_size, ret;
721 io_buffer_size = max_packet_size;
723 io_buffer_size = 1024;
725 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
727 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
730 d->io_buffer_size = io_buffer_size;
734 d->allocated_size = 0;
735 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
737 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
738 max_packet_size ? NULL : dyn_buf_seek);
740 s->max_packet_size = max_packet_size;
746 * Open a write only memory stream.
748 * @param s new IO context
749 * @return zero if no error.
751 int url_open_dyn_buf(ByteIOContext *s)
753 return url_open_dyn_buf_internal(s, 0);
757 * Open a write only packetized memory stream with a maximum packet
758 * size of 'max_packet_size'. The stream is stored in a memory buffer
759 * with a big endian 4 byte header giving the packet size in bytes.
761 * @param s new IO context
762 * @param max_packet_size maximum packet size (must be > 0)
763 * @return zero if no error.
765 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
767 if (max_packet_size <= 0)
769 return url_open_dyn_buf_internal(s, max_packet_size);
773 * Return the written size and a pointer to the buffer. The buffer
774 * must be freed with av_free().
775 * @param s IO context
776 * @param pointer to a byte buffer
777 * @return the length of the byte buffer
779 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
781 DynBuffer *d = s->opaque;
786 *pbuffer = d->buffer;
791 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */