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;
337 len = s->buf_end - s->buf_ptr;
341 memcpy(buf, s->buf_ptr, len);
350 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
354 len = s->buf_end - s->buf_ptr;
357 len = s->buf_end - s->buf_ptr;
361 memcpy(buf, s->buf_ptr, len);
366 unsigned int get_le16(ByteIOContext *s)
370 val |= get_byte(s) << 8;
374 unsigned int get_le32(ByteIOContext *s)
378 val |= get_byte(s) << 8;
379 val |= get_byte(s) << 16;
380 val |= get_byte(s) << 24;
384 uint64_t get_le64(ByteIOContext *s)
387 val = (uint64_t)get_le32(s);
388 val |= (uint64_t)get_le32(s) << 32;
392 unsigned int get_be16(ByteIOContext *s)
395 val = get_byte(s) << 8;
400 unsigned int get_be32(ByteIOContext *s)
403 val = get_byte(s) << 24;
404 val |= get_byte(s) << 16;
405 val |= get_byte(s) << 8;
410 double get_be64_double(ByteIOContext *s)
421 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
426 while ((c = get_byte(s))) {
431 buf[i] = 0; /* Ensure null terminated, but may be truncated */
436 uint64_t get_be64(ByteIOContext *s)
439 val = (uint64_t)get_be32(s) << 32;
440 val |= (uint64_t)get_be32(s);
444 /* link with avio functions */
446 #ifdef CONFIG_ENCODERS
447 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
449 URLContext *h = opaque;
450 return url_write(h, buf, buf_size);
453 #define url_write_packet NULL
454 #endif //CONFIG_ENCODERS
456 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
458 URLContext *h = opaque;
459 return url_read(h, buf, buf_size);
462 static int url_seek_packet(void *opaque, int64_t offset, int whence)
464 URLContext *h = opaque;
465 return url_seek(h, offset, whence);
469 int url_fdopen(ByteIOContext *s, URLContext *h)
472 int buffer_size, max_packet_size;
475 max_packet_size = url_get_max_packet_size(h);
476 if (max_packet_size) {
477 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
479 buffer_size = IO_BUFFER_SIZE;
481 buffer = av_malloc(buffer_size);
485 if (init_put_byte(s, buffer, buffer_size,
486 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
487 url_read_packet, url_write_packet, url_seek_packet) < 0) {
491 s->is_streamed = h->is_streamed;
492 s->max_packet_size = max_packet_size;
496 /* XXX: must be called before any I/O */
497 int url_setbufsize(ByteIOContext *s, int buf_size)
500 buffer = av_malloc(buf_size);
506 s->buffer_size = buf_size;
511 s->buf_end = buffer + buf_size;
515 /* NOTE: when opened as read/write, the buffers are only used for
517 int url_fopen(ByteIOContext *s, const char *filename, int flags)
522 err = url_open(&h, filename, flags);
525 err = url_fdopen(s, h);
533 int url_fclose(ByteIOContext *s)
535 URLContext *h = s->opaque;
538 memset(s, 0, sizeof(ByteIOContext));
542 URLContext *url_fileno(ByteIOContext *s)
547 #ifdef CONFIG_ENCODERS
548 /* XXX: currently size is limited */
549 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
556 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
558 put_buffer(s, buf, strlen(buf));
561 #endif //CONFIG_ENCODERS
563 /* note: unlike fgets, the EOL character is not returned and a whole
564 line is parsed. return NULL if first char read was EOF */
565 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
575 if (c == EOF || c == '\n')
577 if ((q - buf) < buf_size - 1)
587 * Return the maximum packet size associated to packetized buffered file
588 * handle. If the file is not packetized (stream like http or file on
589 * disk), then 0 is returned.
591 * @param h buffered file handle
592 * @return maximum packet size in bytes
594 int url_fget_max_packet_size(ByteIOContext *s)
596 return s->max_packet_size;
599 #ifdef CONFIG_ENCODERS
600 /* buffer handling */
601 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
603 return init_put_byte(s, buf, buf_size,
604 (flags & URL_WRONLY || flags & URL_RDWR),
605 NULL, NULL, NULL, NULL);
608 /* return the written or read size */
609 int url_close_buf(ByteIOContext *s)
612 return s->buf_ptr - s->buffer;
615 /* output in a dynamic buffer */
617 typedef struct DynBuffer {
618 int pos, size, allocated_size;
621 uint8_t io_buffer[1];
624 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
626 DynBuffer *d = opaque;
627 int new_size, new_allocated_size;
629 /* reallocate buffer if needed */
630 new_size = d->pos + buf_size;
631 new_allocated_size = d->allocated_size;
632 if(new_size < d->pos || new_size > INT_MAX/2)
634 while (new_size > new_allocated_size) {
635 if (!new_allocated_size)
636 new_allocated_size = new_size;
638 new_allocated_size += new_allocated_size / 2 + 1;
641 if (new_allocated_size > d->allocated_size) {
642 d->buffer = av_realloc(d->buffer, new_allocated_size);
643 if(d->buffer == NULL)
645 d->allocated_size = new_allocated_size;
647 memcpy(d->buffer + d->pos, buf, buf_size);
649 if (d->pos > d->size)
654 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
656 unsigned char buf1[4];
659 /* packetized write: output the header */
660 buf1[0] = (buf_size >> 24);
661 buf1[1] = (buf_size >> 16);
662 buf1[2] = (buf_size >> 8);
663 buf1[3] = (buf_size);
664 ret= dyn_buf_write(opaque, buf1, 4);
669 return dyn_buf_write(opaque, buf, buf_size);
672 static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
674 DynBuffer *d = opaque;
676 if (whence == SEEK_CUR)
678 else if (whence == SEEK_END)
680 if (offset < 0 || offset > 0x7fffffffLL)
686 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
689 int io_buffer_size, ret;
692 io_buffer_size = max_packet_size;
694 io_buffer_size = 1024;
696 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
698 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
701 d->io_buffer_size = io_buffer_size;
705 d->allocated_size = 0;
706 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
708 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
709 max_packet_size ? NULL : dyn_buf_seek);
711 s->max_packet_size = max_packet_size;
717 * Open a write only memory stream.
719 * @param s new IO context
720 * @return zero if no error.
722 int url_open_dyn_buf(ByteIOContext *s)
724 return url_open_dyn_buf_internal(s, 0);
728 * Open a write only packetized memory stream with a maximum packet
729 * size of 'max_packet_size'. The stream is stored in a memory buffer
730 * with a big endian 4 byte header giving the packet size in bytes.
732 * @param s new IO context
733 * @param max_packet_size maximum packet size (must be > 0)
734 * @return zero if no error.
736 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
738 if (max_packet_size <= 0)
740 return url_open_dyn_buf_internal(s, max_packet_size);
744 * Return the written size and a pointer to the buffer. The buffer
745 * must be freed with av_free().
746 * @param s IO context
747 * @param pointer to a byte buffer
748 * @return the length of the byte buffer
750 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
752 DynBuffer *d = s->opaque;
757 *pbuffer = d->buffer;
762 #endif //CONFIG_ENCODERS