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 void (*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;
50 s->max_packet_size = 0;
51 s->update_checksum= NULL;
56 #ifdef CONFIG_ENCODERS
57 static void flush_buffer(ByteIOContext *s)
59 if (s->buf_ptr > s->buffer) {
61 s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
62 if(s->update_checksum){
63 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
64 s->checksum_ptr= s->buffer;
66 s->pos += s->buf_ptr - s->buffer;
68 s->buf_ptr = s->buffer;
71 void put_byte(ByteIOContext *s, int b)
74 if (s->buf_ptr >= s->buf_end)
78 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
83 len = (s->buf_end - s->buf_ptr);
86 memcpy(s->buf_ptr, buf, len);
89 if (s->buf_ptr >= s->buf_end)
97 void put_flush_packet(ByteIOContext *s)
102 #endif //CONFIG_ENCODERS
104 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
108 if (whence != SEEK_CUR && whence != SEEK_SET)
111 #ifdef CONFIG_ENCODERS
113 if (whence == SEEK_CUR) {
114 offset1 = s->pos + (s->buf_ptr - s->buffer);
119 offset1 = offset - s->pos;
120 if (!s->must_flush &&
121 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
122 /* can do the seek inside the buffer */
123 s->buf_ptr = s->buffer + offset1;
129 s->buf_ptr = s->buffer;
130 s->seek(s->opaque, offset, SEEK_SET);
134 #endif //CONFIG_ENCODERS
136 if (whence == SEEK_CUR) {
137 offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
142 offset1 = offset - (s->pos - (s->buf_end - s->buffer));
143 if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
144 /* can do the seek inside the buffer */
145 s->buf_ptr = s->buffer + offset1;
149 s->buf_ptr = s->buffer;
150 s->buf_end = s->buffer;
151 s->seek(s->opaque, offset, SEEK_SET);
159 void url_fskip(ByteIOContext *s, offset_t offset)
161 url_fseek(s, offset, SEEK_CUR);
164 offset_t url_ftell(ByteIOContext *s)
166 return url_fseek(s, 0, SEEK_CUR);
169 int url_feof(ByteIOContext *s)
171 return s->eof_reached;
174 #ifdef CONFIG_ENCODERS
175 void put_le32(ByteIOContext *s, unsigned int val)
178 put_byte(s, val >> 8);
179 put_byte(s, val >> 16);
180 put_byte(s, val >> 24);
183 void put_be32(ByteIOContext *s, unsigned int val)
185 put_byte(s, val >> 24);
186 put_byte(s, val >> 16);
187 put_byte(s, val >> 8);
191 /* IEEE format is assumed */
192 void put_be64_double(ByteIOContext *s, double val)
202 void put_strz(ByteIOContext *s, const char *str)
205 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
210 void put_le64(ByteIOContext *s, uint64_t val)
212 put_le32(s, (uint32_t)(val & 0xffffffff));
213 put_le32(s, (uint32_t)(val >> 32));
216 void put_be64(ByteIOContext *s, uint64_t val)
218 put_be32(s, (uint32_t)(val >> 32));
219 put_be32(s, (uint32_t)(val & 0xffffffff));
222 void put_le16(ByteIOContext *s, unsigned int val)
225 put_byte(s, val >> 8);
228 void put_be16(ByteIOContext *s, unsigned int val)
230 put_byte(s, val >> 8);
234 void put_tag(ByteIOContext *s, const char *tag)
240 #endif //CONFIG_ENCODERS
244 static void fill_buffer(ByteIOContext *s)
248 /* no need to do anything if EOF already reached */
252 if(s->update_checksum){
253 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
254 s->checksum_ptr= s->buffer;
257 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
259 /* do not modify buffer if EOF reached so that a seek back can
260 be done without rereading data */
264 s->buf_ptr = s->buffer;
265 s->buf_end = s->buffer + len;
269 unsigned long get_checksum(ByteIOContext *s){
270 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
271 s->update_checksum= NULL;
275 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
276 s->update_checksum= update_checksum;
277 if(s->update_checksum){
278 s->checksum= s->update_checksum(checksum, NULL, 0);
279 s->checksum_ptr= s->buf_ptr;
283 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
285 /* XXX: put an inline version */
286 int get_byte(ByteIOContext *s)
288 if (s->buf_ptr < s->buf_end) {
289 return *s->buf_ptr++;
292 if (s->buf_ptr < s->buf_end)
293 return *s->buf_ptr++;
299 /* NOTE: return URL_EOF (-1) if EOF */
300 int url_fgetc(ByteIOContext *s)
302 if (s->buf_ptr < s->buf_end) {
303 return *s->buf_ptr++;
306 if (s->buf_ptr < s->buf_end)
307 return *s->buf_ptr++;
313 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
319 len = s->buf_end - s->buf_ptr;
324 len = s->buf_end - s->buf_ptr;
328 memcpy(buf, s->buf_ptr, len);
337 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
341 len = s->buf_end - s->buf_ptr;
344 len = s->buf_end - s->buf_ptr;
348 memcpy(buf, s->buf_ptr, len);
353 unsigned int get_le16(ByteIOContext *s)
357 val |= get_byte(s) << 8;
361 unsigned int get_le32(ByteIOContext *s)
365 val |= get_byte(s) << 8;
366 val |= get_byte(s) << 16;
367 val |= get_byte(s) << 24;
371 uint64_t get_le64(ByteIOContext *s)
374 val = (uint64_t)get_le32(s);
375 val |= (uint64_t)get_le32(s) << 32;
379 unsigned int get_be16(ByteIOContext *s)
382 val = get_byte(s) << 8;
387 unsigned int get_be32(ByteIOContext *s)
390 val = get_byte(s) << 24;
391 val |= get_byte(s) << 16;
392 val |= get_byte(s) << 8;
397 double get_be64_double(ByteIOContext *s)
408 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
413 while ((c = get_byte(s))) {
418 buf[i] = 0; /* Ensure null terminated, but may be truncated */
423 uint64_t get_be64(ByteIOContext *s)
426 val = (uint64_t)get_be32(s) << 32;
427 val |= (uint64_t)get_be32(s);
431 /* link with avio functions */
433 #ifdef CONFIG_ENCODERS
434 static void url_write_packet(void *opaque, uint8_t *buf, int buf_size)
436 URLContext *h = opaque;
437 url_write(h, buf, buf_size);
440 #define url_write_packet NULL
441 #endif //CONFIG_ENCODERS
443 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
445 URLContext *h = opaque;
446 return url_read(h, buf, buf_size);
449 static int url_seek_packet(void *opaque, int64_t offset, int whence)
451 URLContext *h = opaque;
452 url_seek(h, offset, whence);
456 int url_fdopen(ByteIOContext *s, URLContext *h)
459 int buffer_size, max_packet_size;
462 max_packet_size = url_get_max_packet_size(h);
463 if (max_packet_size) {
464 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
466 buffer_size = IO_BUFFER_SIZE;
468 buffer = av_malloc(buffer_size);
472 if (init_put_byte(s, buffer, buffer_size,
473 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
474 url_read_packet, url_write_packet, url_seek_packet) < 0) {
478 s->is_streamed = h->is_streamed;
479 s->max_packet_size = max_packet_size;
483 /* XXX: must be called before any I/O */
484 int url_setbufsize(ByteIOContext *s, int buf_size)
487 buffer = av_malloc(buf_size);
493 s->buffer_size = buf_size;
498 s->buf_end = buffer + buf_size;
502 /* NOTE: when opened as read/write, the buffers are only used for
504 int url_fopen(ByteIOContext *s, const char *filename, int flags)
509 err = url_open(&h, filename, flags);
512 err = url_fdopen(s, h);
520 int url_fclose(ByteIOContext *s)
522 URLContext *h = s->opaque;
525 memset(s, 0, sizeof(ByteIOContext));
529 URLContext *url_fileno(ByteIOContext *s)
534 #ifdef CONFIG_ENCODERS
535 /* XXX: currently size is limited */
536 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
543 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
545 put_buffer(s, buf, strlen(buf));
548 #endif //CONFIG_ENCODERS
550 /* note: unlike fgets, the EOL character is not returned and a whole
551 line is parsed. return NULL if first char read was EOF */
552 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
562 if (c == EOF || c == '\n')
564 if ((q - buf) < buf_size - 1)
574 * Return the maximum packet size associated to packetized buffered file
575 * handle. If the file is not packetized (stream like http or file on
576 * disk), then 0 is returned.
578 * @param h buffered file handle
579 * @return maximum packet size in bytes
581 int url_fget_max_packet_size(ByteIOContext *s)
583 return s->max_packet_size;
586 #ifdef CONFIG_ENCODERS
587 /* buffer handling */
588 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
590 return init_put_byte(s, buf, buf_size,
591 (flags & URL_WRONLY || flags & URL_RDWR),
592 NULL, NULL, NULL, NULL);
595 /* return the written or read size */
596 int url_close_buf(ByteIOContext *s)
599 return s->buf_ptr - s->buffer;
602 /* output in a dynamic buffer */
604 typedef struct DynBuffer {
605 int pos, size, allocated_size;
608 uint8_t io_buffer[1];
611 static void dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
613 DynBuffer *d = opaque;
614 int new_size, new_allocated_size;
616 /* reallocate buffer if needed */
617 new_size = d->pos + buf_size;
618 new_allocated_size = d->allocated_size;
619 while (new_size > new_allocated_size) {
620 if (!new_allocated_size)
621 new_allocated_size = new_size;
623 new_allocated_size = (new_allocated_size * 3) / 2 + 1;
626 if (new_allocated_size > d->allocated_size) {
627 d->buffer = av_realloc(d->buffer, new_allocated_size);
628 if(d->buffer == NULL)
630 d->allocated_size = new_allocated_size;
632 memcpy(d->buffer + d->pos, buf, buf_size);
634 if (d->pos > d->size)
638 static void dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
640 unsigned char buf1[4];
642 /* packetized write: output the header */
643 buf1[0] = (buf_size >> 24);
644 buf1[1] = (buf_size >> 16);
645 buf1[2] = (buf_size >> 8);
646 buf1[3] = (buf_size);
647 dyn_buf_write(opaque, buf1, 4);
650 dyn_buf_write(opaque, buf, buf_size);
653 static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
655 DynBuffer *d = opaque;
657 if (whence == SEEK_CUR)
659 else if (whence == SEEK_END)
661 if (offset < 0 || offset > 0x7fffffffLL)
667 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
670 int io_buffer_size, ret;
673 io_buffer_size = max_packet_size;
675 io_buffer_size = 1024;
677 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
680 d->io_buffer_size = io_buffer_size;
684 d->allocated_size = 0;
685 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
687 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
688 max_packet_size ? NULL : dyn_buf_seek);
690 s->max_packet_size = max_packet_size;
696 * Open a write only memory stream.
698 * @param s new IO context
699 * @return zero if no error.
701 int url_open_dyn_buf(ByteIOContext *s)
703 return url_open_dyn_buf_internal(s, 0);
707 * Open a write only packetized memory stream with a maximum packet
708 * size of 'max_packet_size'. The stream is stored in a memory buffer
709 * with a big endian 4 byte header giving the packet size in bytes.
711 * @param s new IO context
712 * @param max_packet_size maximum packet size (must be > 0)
713 * @return zero if no error.
715 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
717 if (max_packet_size <= 0)
719 return url_open_dyn_buf_internal(s, max_packet_size);
723 * Return the written size and a pointer to the buffer. The buffer
724 * must be freed with av_free().
725 * @param s IO context
726 * @param pointer to a byte buffer
727 * @return the length of the byte buffer
729 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
731 DynBuffer *d = s->opaque;
736 *pbuffer = d->buffer;
741 #endif //CONFIG_ENCODERS