mpv/libmpdemux/realrtsp/xbuffer.c

87 lines
1.8 KiB
C

/*
* xbuffer code
*
* Includes a minimalistic replacement for xine_buffer functions used in
* Real streaming code. Only function needed by this code are implemented.
*
* Most code comes from xine_buffer.c Copyright (C) 2002 the xine project
*
* WARNING: do not mix original xine_buffer functions with this code!
* xbuffers behave like xine_buffers, but are not byte-compatible with them.
* You must take care of pointers returned by xbuffers functions (no macro to
* do it automatically)
*
*/
#include <stdlib.h>
#include <inttypes.h>
#include "xbuffer.h"
typedef struct {
uint32_t size;
uint32_t chunk_size;
} xbuffer_header_t;
#define XBUFFER_HEADER_SIZE sizeof (xbuffer_header_t)
void *xbuffer_init(int chunk_size) {
uint8_t *data=calloc(1,chunk_size+XBUFFER_HEADER_SIZE);
xbuffer_header_t *header=(xbuffer_header_t*)data;
header->size=chunk_size;
header->chunk_size=chunk_size;
return data+XBUFFER_HEADER_SIZE;
}
void *xbuffer_free(void *buf) {
if (!buf) {
return NULL;
}
free(((uint8_t*)buf)-XBUFFER_HEADER_SIZE);
return NULL;
}
void *xbuffer_copyin(void *buf, int index, const void *data, int len) {
if (!buf || !data) {
return NULL;
}
buf = xbuffer_ensure_size(buf, index+len);
memcpy(((uint8_t*)buf)+index, data, len);
return buf;
}
void *xbuffer_ensure_size(void *buf, int size) {
xbuffer_header_t *xbuf;
int new_size;
if (!buf) {
return 0;
}
xbuf = ((xbuffer_header_t*)(((uint8_t*)buf)-XBUFFER_HEADER_SIZE));
if (xbuf->size < size) {
new_size = size + xbuf->chunk_size - (size % xbuf->chunk_size);
xbuf->size = new_size;
buf = ((uint8_t*)realloc(((uint8_t*)buf)-XBUFFER_HEADER_SIZE,
new_size+XBUFFER_HEADER_SIZE)) + XBUFFER_HEADER_SIZE;
}
return buf;
}