2 * Buffered I/O for ffmpeg system
3 * Copyright (c) 2000,2001 Fabrice Bellard
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #define IO_BUFFER_SIZE 32768
25 int init_put_byte(ByteIOContext *s,
26 unsigned char *buffer,
30 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
31 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
32 offset_t (*seek)(void *opaque, offset_t offset, int whence))
35 s->buffer_size = buffer_size;
37 s->write_flag = write_flag;
41 s->buf_end = buffer + buffer_size;
43 s->write_packet = write_packet;
44 s->read_packet = read_packet;
51 s->max_packet_size = 0;
52 s->update_checksum= NULL;
57 #ifdef CONFIG_ENCODERS
58 static void flush_buffer(ByteIOContext *s)
60 if (s->buf_ptr > s->buffer) {
61 if (s->write_packet && !s->error){
62 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
67 if(s->update_checksum){
68 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
69 s->checksum_ptr= s->buffer;
71 s->pos += s->buf_ptr - s->buffer;
73 s->buf_ptr = s->buffer;
76 void put_byte(ByteIOContext *s, int b)
79 if (s->buf_ptr >= s->buf_end)
83 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
88 len = (s->buf_end - s->buf_ptr);
91 memcpy(s->buf_ptr, buf, len);
94 if (s->buf_ptr >= s->buf_end)
102 void put_flush_packet(ByteIOContext *s)
107 #endif //CONFIG_ENCODERS
109 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
113 if (whence != SEEK_CUR && whence != SEEK_SET)
116 #ifdef CONFIG_ENCODERS
118 if (whence == SEEK_CUR) {
119 offset1 = s->pos + (s->buf_ptr - s->buffer);
124 offset1 = offset - s->pos;
125 if (!s->must_flush &&
126 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
127 /* can do the seek inside the buffer */
128 s->buf_ptr = s->buffer + offset1;
134 s->buf_ptr = s->buffer;
135 s->seek(s->opaque, offset, SEEK_SET);
139 #endif //CONFIG_ENCODERS
141 if (whence == SEEK_CUR) {
142 offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
147 offset1 = offset - (s->pos - (s->buf_end - s->buffer));
148 if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
149 /* can do the seek inside the buffer */
150 s->buf_ptr = s->buffer + offset1;
154 s->buf_ptr = s->buffer;
155 s->buf_end = s->buffer;
156 if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
165 void url_fskip(ByteIOContext *s, offset_t offset)
167 url_fseek(s, offset, SEEK_CUR);
170 offset_t url_ftell(ByteIOContext *s)
172 return url_fseek(s, 0, SEEK_CUR);
175 offset_t url_fsize(ByteIOContext *s)
181 size = s->seek(s->opaque, -1, SEEK_END) + 1;
182 s->seek(s->opaque, s->pos, SEEK_SET);
186 int url_feof(ByteIOContext *s)
188 return s->eof_reached;
191 int url_ferror(ByteIOContext *s)
196 #ifdef CONFIG_ENCODERS
197 void put_le32(ByteIOContext *s, unsigned int val)
200 put_byte(s, val >> 8);
201 put_byte(s, val >> 16);
202 put_byte(s, val >> 24);
205 void put_be32(ByteIOContext *s, unsigned int val)
207 put_byte(s, val >> 24);
208 put_byte(s, val >> 16);
209 put_byte(s, val >> 8);
213 void put_strz(ByteIOContext *s, const char *str)
216 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
221 void put_le64(ByteIOContext *s, uint64_t val)
223 put_le32(s, (uint32_t)(val & 0xffffffff));
224 put_le32(s, (uint32_t)(val >> 32));
227 void put_be64(ByteIOContext *s, uint64_t val)
229 put_be32(s, (uint32_t)(val >> 32));
230 put_be32(s, (uint32_t)(val & 0xffffffff));
233 void put_le16(ByteIOContext *s, unsigned int val)
236 put_byte(s, val >> 8);
239 void put_be16(ByteIOContext *s, unsigned int val)
241 put_byte(s, val >> 8);
245 void put_be24(ByteIOContext *s, unsigned int val)
247 put_be16(s, val >> 8);
251 void put_tag(ByteIOContext *s, const char *tag)
257 #endif //CONFIG_ENCODERS
261 static void fill_buffer(ByteIOContext *s)
265 /* no need to do anything if EOF already reached */
269 if(s->update_checksum){
270 if(s->buf_end > s->checksum_ptr)
271 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
272 s->checksum_ptr= s->buffer;
275 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
277 /* do not modify buffer if EOF reached so that a seek back can
278 be done without rereading data */
284 s->buf_ptr = s->buffer;
285 s->buf_end = s->buffer + len;
289 unsigned long get_checksum(ByteIOContext *s){
290 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
291 s->update_checksum= NULL;
295 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
296 s->update_checksum= update_checksum;
297 if(s->update_checksum){
298 s->checksum= s->update_checksum(checksum, NULL, 0);
299 s->checksum_ptr= s->buf_ptr;
303 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
305 /* XXX: put an inline version */
306 int get_byte(ByteIOContext *s)
308 if (s->buf_ptr < s->buf_end) {
309 return *s->buf_ptr++;
312 if (s->buf_ptr < s->buf_end)
313 return *s->buf_ptr++;
319 /* NOTE: return URL_EOF (-1) if EOF */
320 int url_fgetc(ByteIOContext *s)
322 if (s->buf_ptr < s->buf_end) {
323 return *s->buf_ptr++;
326 if (s->buf_ptr < s->buf_end)
327 return *s->buf_ptr++;
333 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
339 len = s->buf_end - s->buf_ptr;
343 if(size > s->buffer_size && !s->update_checksum){
344 len = s->read_packet(s->opaque, buf, size);
346 /* do not modify buffer if EOF reached so that a seek back can
347 be done without rereading data */
356 s->buf_ptr = s->buffer;
357 s->buf_end = s->buffer/* + len*/;
361 len = s->buf_end - s->buf_ptr;
366 memcpy(buf, s->buf_ptr, len);
375 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
382 len = s->buf_end - s->buf_ptr;
385 len = s->buf_end - s->buf_ptr;
389 memcpy(buf, s->buf_ptr, len);
394 unsigned int get_le16(ByteIOContext *s)
398 val |= get_byte(s) << 8;
402 unsigned int get_le32(ByteIOContext *s)
406 val |= get_le16(s) << 16;
410 uint64_t get_le64(ByteIOContext *s)
413 val = (uint64_t)get_le32(s);
414 val |= (uint64_t)get_le32(s) << 32;
418 unsigned int get_be16(ByteIOContext *s)
421 val = get_byte(s) << 8;
426 unsigned int get_be24(ByteIOContext *s)
429 val = get_be16(s) << 8;
433 unsigned int get_be32(ByteIOContext *s)
436 val = get_be16(s) << 16;
441 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
446 while ((c = get_byte(s))) {
451 buf[i] = 0; /* Ensure null terminated, but may be truncated */
456 uint64_t get_be64(ByteIOContext *s)
459 val = (uint64_t)get_be32(s) << 32;
460 val |= (uint64_t)get_be32(s);
464 /* link with avio functions */
466 #ifdef CONFIG_ENCODERS
467 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
469 URLContext *h = opaque;
470 return url_write(h, buf, buf_size);
473 #define url_write_packet NULL
474 #endif //CONFIG_ENCODERS
476 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
478 URLContext *h = opaque;
479 return url_read(h, buf, buf_size);
482 static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
484 URLContext *h = opaque;
485 return url_seek(h, offset, whence);
489 int url_fdopen(ByteIOContext *s, URLContext *h)
492 int buffer_size, max_packet_size;
495 max_packet_size = url_get_max_packet_size(h);
496 if (max_packet_size) {
497 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
499 buffer_size = IO_BUFFER_SIZE;
501 buffer = av_malloc(buffer_size);
505 if (init_put_byte(s, buffer, buffer_size,
506 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
507 url_read_packet, url_write_packet, url_seek_packet) < 0) {
511 s->is_streamed = h->is_streamed;
512 s->max_packet_size = max_packet_size;
516 /* XXX: must be called before any I/O */
517 int url_setbufsize(ByteIOContext *s, int buf_size)
520 buffer = av_malloc(buf_size);
526 s->buffer_size = buf_size;
531 s->buf_end = buffer + buf_size;
535 /* NOTE: when opened as read/write, the buffers are only used for
537 int url_fopen(ByteIOContext *s, const char *filename, int flags)
542 err = url_open(&h, filename, flags);
545 err = url_fdopen(s, h);
553 int url_fclose(ByteIOContext *s)
555 URLContext *h = s->opaque;
558 memset(s, 0, sizeof(ByteIOContext));
562 URLContext *url_fileno(ByteIOContext *s)
567 #ifdef CONFIG_ENCODERS
568 /* XXX: currently size is limited */
569 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
576 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
578 put_buffer(s, buf, strlen(buf));
581 #endif //CONFIG_ENCODERS
583 /* note: unlike fgets, the EOL character is not returned and a whole
584 line is parsed. return NULL if first char read was EOF */
585 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
595 if (c == EOF || c == '\n')
597 if ((q - buf) < buf_size - 1)
607 * Return the maximum packet size associated to packetized buffered file
608 * handle. If the file is not packetized (stream like http or file on
609 * disk), then 0 is returned.
611 * @param h buffered file handle
612 * @return maximum packet size in bytes
614 int url_fget_max_packet_size(ByteIOContext *s)
616 return s->max_packet_size;
619 #ifdef CONFIG_ENCODERS
620 /* buffer handling */
621 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
623 return init_put_byte(s, buf, buf_size,
624 (flags & URL_WRONLY || flags & URL_RDWR),
625 NULL, NULL, NULL, NULL);
628 /* return the written or read size */
629 int url_close_buf(ByteIOContext *s)
632 return s->buf_ptr - s->buffer;
635 /* output in a dynamic buffer */
637 typedef struct DynBuffer {
638 int pos, size, allocated_size;
641 uint8_t io_buffer[1];
644 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
646 DynBuffer *d = opaque;
647 int new_size, new_allocated_size;
649 /* reallocate buffer if needed */
650 new_size = d->pos + buf_size;
651 new_allocated_size = d->allocated_size;
652 if(new_size < d->pos || new_size > INT_MAX/2)
654 while (new_size > new_allocated_size) {
655 if (!new_allocated_size)
656 new_allocated_size = new_size;
658 new_allocated_size += new_allocated_size / 2 + 1;
661 if (new_allocated_size > d->allocated_size) {
662 d->buffer = av_realloc(d->buffer, new_allocated_size);
663 if(d->buffer == NULL)
665 d->allocated_size = new_allocated_size;
667 memcpy(d->buffer + d->pos, buf, buf_size);
669 if (d->pos > d->size)
674 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
676 unsigned char buf1[4];
679 /* packetized write: output the header */
680 buf1[0] = (buf_size >> 24);
681 buf1[1] = (buf_size >> 16);
682 buf1[2] = (buf_size >> 8);
683 buf1[3] = (buf_size);
684 ret= dyn_buf_write(opaque, buf1, 4);
689 return dyn_buf_write(opaque, buf, buf_size);
692 static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
694 DynBuffer *d = opaque;
696 if (whence == SEEK_CUR)
698 else if (whence == SEEK_END)
700 if (offset < 0 || offset > 0x7fffffffLL)
706 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
709 int io_buffer_size, ret;
712 io_buffer_size = max_packet_size;
714 io_buffer_size = 1024;
716 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
718 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
721 d->io_buffer_size = io_buffer_size;
725 d->allocated_size = 0;
726 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
728 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
729 max_packet_size ? NULL : dyn_buf_seek);
731 s->max_packet_size = max_packet_size;
737 * Open a write only memory stream.
739 * @param s new IO context
740 * @return zero if no error.
742 int url_open_dyn_buf(ByteIOContext *s)
744 return url_open_dyn_buf_internal(s, 0);
748 * Open a write only packetized memory stream with a maximum packet
749 * size of 'max_packet_size'. The stream is stored in a memory buffer
750 * with a big endian 4 byte header giving the packet size in bytes.
752 * @param s new IO context
753 * @param max_packet_size maximum packet size (must be > 0)
754 * @return zero if no error.
756 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
758 if (max_packet_size <= 0)
760 return url_open_dyn_buf_internal(s, max_packet_size);
764 * Return the written size and a pointer to the buffer. The buffer
765 * must be freed with av_free().
766 * @param s IO context
767 * @param pointer to a byte buffer
768 * @return the length of the byte buffer
770 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
772 DynBuffer *d = s->opaque;
777 *pbuffer = d->buffer;
782 #endif //CONFIG_ENCODERS