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  * This file is part of MPlayer.
  15  *
  16  * MPlayer is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * MPlayer is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License along
  27  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  28  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  29  */
  30
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <inttypes.h>
  34 #include "xbuffer.h"
  35
  36
  37 typedef struct {
  38   uint32_t size;
  39   uint32_t chunk_size;
  40 } xbuffer_header_t;
  41
  42 #define XBUFFER_HEADER_SIZE sizeof (xbuffer_header_t)
  43
  44
  45
  46 void *xbuffer_init(int chunk_size) {
  47   uint8_t *data=calloc(1,chunk_size+XBUFFER_HEADER_SIZE);
  48
  49   xbuffer_header_t *header=(xbuffer_header_t*)data;
  50
  51   header->size=chunk_size;
  52   header->chunk_size=chunk_size;
  53
  54   return data+XBUFFER_HEADER_SIZE;
  55 }
  56
  57
  58
  59 void *xbuffer_free(void *buf) {
  60   if (!buf) {
  61     return NULL;
  62   }
  63
  64   free(((uint8_t*)buf)-XBUFFER_HEADER_SIZE);
  65
  66   return NULL;
  67 }
  68
  69
  70
  71 void *xbuffer_copyin(void *buf, int index, const void *data, int len) {
  72     if (!buf || !data) {
  73     return NULL;
  74   }
  75
  76   buf = xbuffer_ensure_size(buf, index+len);
  77   memcpy(((uint8_t*)buf)+index, data, len);
  78
  79   return buf;
  80 }
  81
  82
  83
  84 void *xbuffer_ensure_size(void *buf, int size) {
  85   xbuffer_header_t *xbuf;
  86   int new_size;
  87
  88   if (!buf) {
  89     return 0;
  90   }
  91
  92   xbuf = ((xbuffer_header_t*)(((uint8_t*)buf)-XBUFFER_HEADER_SIZE));
  93
  94   if (xbuf->size < size) {
  95     new_size = size + xbuf->chunk_size - (size % xbuf->chunk_size);
  96     xbuf->size = new_size;
  97     buf = ((uint8_t*)realloc(((uint8_t*)buf)-XBUFFER_HEADER_SIZE,
  98           new_size+XBUFFER_HEADER_SIZE)) + XBUFFER_HEADER_SIZE;
  99   }
 100
 101   return buf;
 102 }
 103
 104
 105
 106 void *xbuffer_strcat(void *buf, char *data) {
 107
 108   if (!buf || !data) {
 109     return NULL;
 110   }
 111
 112   buf = xbuffer_ensure_size(buf, strlen(buf)+strlen(data)+1);
 113
 114   strcat(buf, data);
 115
 116   return buf;
 117 }