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 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 /* IEEE format is assumed */
214 void put_be64_double(ByteIOContext *s, double val)
224 void put_strz(ByteIOContext *s, const char *str)
227 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
232 void put_le64(ByteIOContext *s, uint64_t val)
234 put_le32(s, (uint32_t)(val & 0xffffffff));
235 put_le32(s, (uint32_t)(val >> 32));
238 void put_be64(ByteIOContext *s, uint64_t val)
240 put_be32(s, (uint32_t)(val >> 32));
241 put_be32(s, (uint32_t)(val & 0xffffffff));
244 void put_le16(ByteIOContext *s, unsigned int val)
247 put_byte(s, val >> 8);
250 void put_be16(ByteIOContext *s, unsigned int val)
252 put_byte(s, val >> 8);
256 void put_tag(ByteIOContext *s, const char *tag)
262 #endif //CONFIG_ENCODERS
266 static void fill_buffer(ByteIOContext *s)
270 /* no need to do anything if EOF already reached */
274 if(s->update_checksum){
275 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
276 s->checksum_ptr= s->buffer;
279 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
281 /* do not modify buffer if EOF reached so that a seek back can
282 be done without rereading data */
288 s->buf_ptr = s->buffer;
289 s->buf_end = s->buffer + len;
293 unsigned long get_checksum(ByteIOContext *s){
294 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
295 s->update_checksum= NULL;
299 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
300 s->update_checksum= update_checksum;
301 if(s->update_checksum){
302 s->checksum= s->update_checksum(checksum, NULL, 0);
303 s->checksum_ptr= s->buf_ptr;
307 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
309 /* XXX: put an inline version */
310 int get_byte(ByteIOContext *s)
312 if (s->buf_ptr < s->buf_end) {
313 return *s->buf_ptr++;
316 if (s->buf_ptr < s->buf_end)
317 return *s->buf_ptr++;
323 /* NOTE: return URL_EOF (-1) if EOF */
324 int url_fgetc(ByteIOContext *s)
326 if (s->buf_ptr < s->buf_end) {
327 return *s->buf_ptr++;
330 if (s->buf_ptr < s->buf_end)
331 return *s->buf_ptr++;
337 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
343 len = s->buf_end - s->buf_ptr;
347 if(size > s->buffer_size && !s->update_checksum){
348 len = s->read_packet(s->opaque, buf, size);
350 /* do not modify buffer if EOF reached so that a seek back can
351 be done without rereading data */
360 s->buf_ptr = s->buffer;
361 s->buf_end = s->buffer/* + len*/;
365 len = s->buf_end - s->buf_ptr;
370 memcpy(buf, s->buf_ptr, len);
379 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
386 len = s->buf_end - s->buf_ptr;
389 len = s->buf_end - s->buf_ptr;
393 memcpy(buf, s->buf_ptr, len);
398 unsigned int get_le16(ByteIOContext *s)
402 val |= get_byte(s) << 8;
406 unsigned int get_le32(ByteIOContext *s)
410 val |= get_byte(s) << 8;
411 val |= get_byte(s) << 16;
412 val |= get_byte(s) << 24;
416 uint64_t get_le64(ByteIOContext *s)
419 val = (uint64_t)get_le32(s);
420 val |= (uint64_t)get_le32(s) << 32;
424 unsigned int get_be16(ByteIOContext *s)
427 val = get_byte(s) << 8;
432 unsigned int get_be32(ByteIOContext *s)
435 val = get_byte(s) << 24;
436 val |= get_byte(s) << 16;
437 val |= get_byte(s) << 8;
442 double get_be64_double(ByteIOContext *s)
453 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
458 while ((c = get_byte(s))) {
463 buf[i] = 0; /* Ensure null terminated, but may be truncated */
468 uint64_t get_be64(ByteIOContext *s)
471 val = (uint64_t)get_be32(s) << 32;
472 val |= (uint64_t)get_be32(s);
476 /* link with avio functions */
478 #ifdef CONFIG_ENCODERS
479 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
481 URLContext *h = opaque;
482 return url_write(h, buf, buf_size);
485 #define url_write_packet NULL
486 #endif //CONFIG_ENCODERS
488 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
490 URLContext *h = opaque;
491 return url_read(h, buf, buf_size);
494 static int url_seek_packet(void *opaque, int64_t offset, int whence)
496 URLContext *h = opaque;
497 return url_seek(h, offset, whence);
501 int url_fdopen(ByteIOContext *s, URLContext *h)
504 int buffer_size, max_packet_size;
507 max_packet_size = url_get_max_packet_size(h);
508 if (max_packet_size) {
509 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
511 buffer_size = IO_BUFFER_SIZE;
513 buffer = av_malloc(buffer_size);
517 if (init_put_byte(s, buffer, buffer_size,
518 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
519 url_read_packet, url_write_packet, url_seek_packet) < 0) {
523 s->is_streamed = h->is_streamed;
524 s->max_packet_size = max_packet_size;
528 /* XXX: must be called before any I/O */
529 int url_setbufsize(ByteIOContext *s, int buf_size)
532 buffer = av_malloc(buf_size);
538 s->buffer_size = buf_size;
543 s->buf_end = buffer + buf_size;
547 /* NOTE: when opened as read/write, the buffers are only used for
549 int url_fopen(ByteIOContext *s, const char *filename, int flags)
554 err = url_open(&h, filename, flags);
557 err = url_fdopen(s, h);
565 int url_fclose(ByteIOContext *s)
567 URLContext *h = s->opaque;
570 memset(s, 0, sizeof(ByteIOContext));
574 URLContext *url_fileno(ByteIOContext *s)
579 #ifdef CONFIG_ENCODERS
580 /* XXX: currently size is limited */
581 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
588 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
590 put_buffer(s, buf, strlen(buf));
593 #endif //CONFIG_ENCODERS
595 /* note: unlike fgets, the EOL character is not returned and a whole
596 line is parsed. return NULL if first char read was EOF */
597 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
607 if (c == EOF || c == '\n')
609 if ((q - buf) < buf_size - 1)
619 * Return the maximum packet size associated to packetized buffered file
620 * handle. If the file is not packetized (stream like http or file on
621 * disk), then 0 is returned.
623 * @param h buffered file handle
624 * @return maximum packet size in bytes
626 int url_fget_max_packet_size(ByteIOContext *s)
628 return s->max_packet_size;
631 #ifdef CONFIG_ENCODERS
632 /* buffer handling */
633 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
635 return init_put_byte(s, buf, buf_size,
636 (flags & URL_WRONLY || flags & URL_RDWR),
637 NULL, NULL, NULL, NULL);
640 /* return the written or read size */
641 int url_close_buf(ByteIOContext *s)
644 return s->buf_ptr - s->buffer;
647 /* output in a dynamic buffer */
649 typedef struct DynBuffer {
650 int pos, size, allocated_size;
653 uint8_t io_buffer[1];
656 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
658 DynBuffer *d = opaque;
659 int new_size, new_allocated_size;
661 /* reallocate buffer if needed */
662 new_size = d->pos + buf_size;
663 new_allocated_size = d->allocated_size;
664 if(new_size < d->pos || new_size > INT_MAX/2)
666 while (new_size > new_allocated_size) {
667 if (!new_allocated_size)
668 new_allocated_size = new_size;
670 new_allocated_size += new_allocated_size / 2 + 1;
673 if (new_allocated_size > d->allocated_size) {
674 d->buffer = av_realloc(d->buffer, new_allocated_size);
675 if(d->buffer == NULL)
677 d->allocated_size = new_allocated_size;
679 memcpy(d->buffer + d->pos, buf, buf_size);
681 if (d->pos > d->size)
686 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
688 unsigned char buf1[4];
691 /* packetized write: output the header */
692 buf1[0] = (buf_size >> 24);
693 buf1[1] = (buf_size >> 16);
694 buf1[2] = (buf_size >> 8);
695 buf1[3] = (buf_size);
696 ret= dyn_buf_write(opaque, buf1, 4);
701 return dyn_buf_write(opaque, buf, buf_size);
704 static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
706 DynBuffer *d = opaque;
708 if (whence == SEEK_CUR)
710 else if (whence == SEEK_END)
712 if (offset < 0 || offset > 0x7fffffffLL)
718 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
721 int io_buffer_size, ret;
724 io_buffer_size = max_packet_size;
726 io_buffer_size = 1024;
728 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
730 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
733 d->io_buffer_size = io_buffer_size;
737 d->allocated_size = 0;
738 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
740 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
741 max_packet_size ? NULL : dyn_buf_seek);
743 s->max_packet_size = max_packet_size;
749 * Open a write only memory stream.
751 * @param s new IO context
752 * @return zero if no error.
754 int url_open_dyn_buf(ByteIOContext *s)
756 return url_open_dyn_buf_internal(s, 0);
760 * Open a write only packetized memory stream with a maximum packet
761 * size of 'max_packet_size'. The stream is stored in a memory buffer
762 * with a big endian 4 byte header giving the packet size in bytes.
764 * @param s new IO context
765 * @param max_packet_size maximum packet size (must be > 0)
766 * @return zero if no error.
768 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
770 if (max_packet_size <= 0)
772 return url_open_dyn_buf_internal(s, max_packet_size);
776 * Return the written size and a pointer to the buffer. The buffer
777 * must be freed with av_free().
778 * @param s IO context
779 * @param pointer to a byte buffer
780 * @return the length of the byte buffer
782 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
784 DynBuffer *d = s->opaque;
789 *pbuffer = d->buffer;
794 #endif //CONFIG_ENCODERS