stream/realrtsp/xbuffer.c

   1 /*
   2  * xbuffer code
   3  *
   4  * Includes a minimalistic replacement for xine_buffer functions used in
   5  * Real streaming code. Only function needed by this code are implemented.
   6  *
   7  * Most code comes from xine_buffer.c Copyright (C) 2002 the xine project
   8  *
   9  * WARNING: do not mix original xine_buffer functions with this code!
  10  * xbuffers behave like xine_buffers, but are not byte-compatible with them.
  11  * You must take care of pointers returned by xbuffers functions (no macro to
  12  * do it automatically)
  13  *
  14  */
  15
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <inttypes.h>
  19 #include "xbuffer.h"
  20
  21
  22 typedef struct {
  23   uint32_t size;
  24   uint32_t chunk_size;
  25 } xbuffer_header_t;
  26
  27 #define XBUFFER_HEADER_SIZE sizeof (xbuffer_header_t)
  28
  29
  30
  31 void *xbuffer_init(int chunk_size) {
  32   uint8_t *data=calloc(1,chunk_size+XBUFFER_HEADER_SIZE);
  33
  34   xbuffer_header_t *header=(xbuffer_header_t*)data;
  35
  36   header->size=chunk_size;
  37   header->chunk_size=chunk_size;
  38
  39   return data+XBUFFER_HEADER_SIZE;
  40 }
  41
  42
  43
  44 void *xbuffer_free(void *buf) {
  45   if (!buf) {
  46     return NULL;
  47   }
  48
  49   free(((uint8_t*)buf)-XBUFFER_HEADER_SIZE);
  50
  51   return NULL;
  52 }
  53
  54
  55
  56 void *xbuffer_copyin(void *buf, int index, const void *data, int len) {
  57     if (!buf || !data) {
  58     return NULL;
  59   }
  60
  61   buf = xbuffer_ensure_size(buf, index+len);
  62   memcpy(((uint8_t*)buf)+index, data, len);
  63
  64   return buf;
  65 }
  66
  67
  68
  69 void *xbuffer_ensure_size(void *buf, int size) {
  70   xbuffer_header_t *xbuf;
  71   int new_size;
  72
  73   if (!buf) {
  74     return 0;
  75   }
  76
  77   xbuf = ((xbuffer_header_t*)(((uint8_t*)buf)-XBUFFER_HEADER_SIZE));
  78
  79   if (xbuf->size < size) {
  80     new_size = size + xbuf->chunk_size - (size % xbuf->chunk_size);
  81     xbuf->size = new_size;
  82     buf = ((uint8_t*)realloc(((uint8_t*)buf)-XBUFFER_HEADER_SIZE,
  83           new_size+XBUFFER_HEADER_SIZE)) + XBUFFER_HEADER_SIZE;
  84   }
  85
  86   return buf;
  87 }
  88
  89
  90
  91 void *xbuffer_strcat(void *buf, char *data) {
  92
  93   if (!buf || !data) {
  94     return NULL;
  95   }
  96
  97   buf = xbuffer_ensure_size(buf, strlen(buf)+strlen(data)+1);
  98
  99   strcat(buf, data);
 100
 101   return buf;
 102 }