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 int (*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 int url_feof(ByteIOContext *s)
177 return s->eof_reached;
180 int url_ferror(ByteIOContext *s)
185 #ifdef CONFIG_ENCODERS
186 void put_le32(ByteIOContext *s, unsigned int val)
189 put_byte(s, val >> 8);
190 put_byte(s, val >> 16);
191 put_byte(s, val >> 24);
194 void put_be32(ByteIOContext *s, unsigned int val)
196 put_byte(s, val >> 24);
197 put_byte(s, val >> 16);
198 put_byte(s, val >> 8);
202 /* IEEE format is assumed */
203 void put_be64_double(ByteIOContext *s, double val)
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_tag(ByteIOContext *s, const char *tag)
251 #endif //CONFIG_ENCODERS
255 static void fill_buffer(ByteIOContext *s)
259 /* no need to do anything if EOF already reached */
263 if(s->update_checksum){
264 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
265 s->checksum_ptr= s->buffer;
268 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
270 /* do not modify buffer if EOF reached so that a seek back can
271 be done without rereading data */
277 s->buf_ptr = s->buffer;
278 s->buf_end = s->buffer + len;
282 unsigned long get_checksum(ByteIOContext *s){
283 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
284 s->update_checksum= NULL;
288 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
289 s->update_checksum= update_checksum;
290 if(s->update_checksum){
291 s->checksum= s->update_checksum(checksum, NULL, 0);
292 s->checksum_ptr= s->buf_ptr;
296 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
298 /* XXX: put an inline version */
299 int get_byte(ByteIOContext *s)
301 if (s->buf_ptr < s->buf_end) {
302 return *s->buf_ptr++;
305 if (s->buf_ptr < s->buf_end)
306 return *s->buf_ptr++;
312 /* NOTE: return URL_EOF (-1) if EOF */
313 int url_fgetc(ByteIOContext *s)
315 if (s->buf_ptr < s->buf_end) {
316 return *s->buf_ptr++;
319 if (s->buf_ptr < s->buf_end)
320 return *s->buf_ptr++;
326 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
332 len = s->buf_end - s->buf_ptr;
336 if(size > s->buffer_size && !s->update_checksum){
337 len = s->read_packet(s->opaque, buf, size);
339 /* do not modify buffer if EOF reached so that a seek back can
340 be done without rereading data */
349 s->buf_ptr = s->buffer;
350 s->buf_end = s->buffer/* + len*/;
354 len = s->buf_end - s->buf_ptr;
359 memcpy(buf, s->buf_ptr, len);
368 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
375 len = s->buf_end - s->buf_ptr;
378 len = s->buf_end - s->buf_ptr;
382 memcpy(buf, s->buf_ptr, len);
387 unsigned int get_le16(ByteIOContext *s)
391 val |= get_byte(s) << 8;
395 unsigned int get_le32(ByteIOContext *s)
399 val |= get_byte(s) << 8;
400 val |= get_byte(s) << 16;
401 val |= get_byte(s) << 24;
405 uint64_t get_le64(ByteIOContext *s)
408 val = (uint64_t)get_le32(s);
409 val |= (uint64_t)get_le32(s) << 32;
413 unsigned int get_be16(ByteIOContext *s)
416 val = get_byte(s) << 8;
421 unsigned int get_be32(ByteIOContext *s)
424 val = get_byte(s) << 24;
425 val |= get_byte(s) << 16;
426 val |= get_byte(s) << 8;
431 double get_be64_double(ByteIOContext *s)
442 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
447 while ((c = get_byte(s))) {
452 buf[i] = 0; /* Ensure null terminated, but may be truncated */
457 uint64_t get_be64(ByteIOContext *s)
460 val = (uint64_t)get_be32(s) << 32;
461 val |= (uint64_t)get_be32(s);
465 /* link with avio functions */
467 #ifdef CONFIG_ENCODERS
468 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
470 URLContext *h = opaque;
471 return url_write(h, buf, buf_size);
474 #define url_write_packet NULL
475 #endif //CONFIG_ENCODERS
477 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
479 URLContext *h = opaque;
480 return url_read(h, buf, buf_size);
483 static int url_seek_packet(void *opaque, int64_t offset, int whence)
485 URLContext *h = opaque;
486 return url_seek(h, offset, whence);
490 int url_fdopen(ByteIOContext *s, URLContext *h)
493 int buffer_size, max_packet_size;
496 max_packet_size = url_get_max_packet_size(h);
497 if (max_packet_size) {
498 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
500 buffer_size = IO_BUFFER_SIZE;
502 buffer = av_malloc(buffer_size);
506 if (init_put_byte(s, buffer, buffer_size,
507 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
508 url_read_packet, url_write_packet, url_seek_packet) < 0) {
512 s->is_streamed = h->is_streamed;
513 s->max_packet_size = max_packet_size;
517 /* XXX: must be called before any I/O */
518 int url_setbufsize(ByteIOContext *s, int buf_size)
521 buffer = av_malloc(buf_size);
527 s->buffer_size = buf_size;
532 s->buf_end = buffer + buf_size;
536 /* NOTE: when opened as read/write, the buffers are only used for
538 int url_fopen(ByteIOContext *s, const char *filename, int flags)
543 err = url_open(&h, filename, flags);
546 err = url_fdopen(s, h);
554 int url_fclose(ByteIOContext *s)
556 URLContext *h = s->opaque;
559 memset(s, 0, sizeof(ByteIOContext));
563 URLContext *url_fileno(ByteIOContext *s)
568 #ifdef CONFIG_ENCODERS
569 /* XXX: currently size is limited */
570 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
577 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
579 put_buffer(s, buf, strlen(buf));
582 #endif //CONFIG_ENCODERS
584 /* note: unlike fgets, the EOL character is not returned and a whole
585 line is parsed. return NULL if first char read was EOF */
586 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
596 if (c == EOF || c == '\n')
598 if ((q - buf) < buf_size - 1)
608 * Return the maximum packet size associated to packetized buffered file
609 * handle. If the file is not packetized (stream like http or file on
610 * disk), then 0 is returned.
612 * @param h buffered file handle
613 * @return maximum packet size in bytes
615 int url_fget_max_packet_size(ByteIOContext *s)
617 return s->max_packet_size;
620 #ifdef CONFIG_ENCODERS
621 /* buffer handling */
622 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
624 return init_put_byte(s, buf, buf_size,
625 (flags & URL_WRONLY || flags & URL_RDWR),
626 NULL, NULL, NULL, NULL);
629 /* return the written or read size */
630 int url_close_buf(ByteIOContext *s)
633 return s->buf_ptr - s->buffer;
636 /* output in a dynamic buffer */
638 typedef struct DynBuffer {
639 int pos, size, allocated_size;
642 uint8_t io_buffer[1];
645 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
647 DynBuffer *d = opaque;
648 int new_size, new_allocated_size;
650 /* reallocate buffer if needed */
651 new_size = d->pos + buf_size;
652 new_allocated_size = d->allocated_size;
653 if(new_size < d->pos || new_size > INT_MAX/2)
655 while (new_size > new_allocated_size) {
656 if (!new_allocated_size)
657 new_allocated_size = new_size;
659 new_allocated_size += new_allocated_size / 2 + 1;
662 if (new_allocated_size > d->allocated_size) {
663 d->buffer = av_realloc(d->buffer, new_allocated_size);
664 if(d->buffer == NULL)
666 d->allocated_size = new_allocated_size;
668 memcpy(d->buffer + d->pos, buf, buf_size);
670 if (d->pos > d->size)
675 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
677 unsigned char buf1[4];
680 /* packetized write: output the header */
681 buf1[0] = (buf_size >> 24);
682 buf1[1] = (buf_size >> 16);
683 buf1[2] = (buf_size >> 8);
684 buf1[3] = (buf_size);
685 ret= dyn_buf_write(opaque, buf1, 4);
690 return dyn_buf_write(opaque, buf, buf_size);
693 static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
695 DynBuffer *d = opaque;
697 if (whence == SEEK_CUR)
699 else if (whence == SEEK_END)
701 if (offset < 0 || offset > 0x7fffffffLL)
707 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
710 int io_buffer_size, ret;
713 io_buffer_size = max_packet_size;
715 io_buffer_size = 1024;
717 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
719 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
722 d->io_buffer_size = io_buffer_size;
726 d->allocated_size = 0;
727 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
729 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
730 max_packet_size ? NULL : dyn_buf_seek);
732 s->max_packet_size = max_packet_size;
738 * Open a write only memory stream.
740 * @param s new IO context
741 * @return zero if no error.
743 int url_open_dyn_buf(ByteIOContext *s)
745 return url_open_dyn_buf_internal(s, 0);
749 * Open a write only packetized memory stream with a maximum packet
750 * size of 'max_packet_size'. The stream is stored in a memory buffer
751 * with a big endian 4 byte header giving the packet size in bytes.
753 * @param s new IO context
754 * @param max_packet_size maximum packet size (must be > 0)
755 * @return zero if no error.
757 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
759 if (max_packet_size <= 0)
761 return url_open_dyn_buf_internal(s, max_packet_size);
765 * Return the written size and a pointer to the buffer. The buffer
766 * must be freed with av_free().
767 * @param s IO context
768 * @param pointer to a byte buffer
769 * @return the length of the byte buffer
771 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
773 DynBuffer *d = s->opaque;
778 *pbuffer = d->buffer;
783 #endif //CONFIG_ENCODERS