code.delx.au - pulseaudio/blob - src/pulsecore/memchunk.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <assert.h>
  29 #include <string.h>
  30
  31 #include <pulse/xmalloc.h>
  32
  33 #include "memchunk.h"
  34
  35 void pa_memchunk_make_writable(pa_memchunk *c, size_t min) {
  36     pa_memblock *n;
  37     size_t l;
  38
  39     assert(c);
  40     assert(c->memblock);
  41     assert(PA_REFCNT_VALUE(c->memblock) > 0);
  42
  43     if (PA_REFCNT_VALUE(c->memblock) == 1 &&
  44         !c->memblock->read_only &&
  45         c->memblock->length >= c->index+min)
  46         return;
  47
  48     l = c->length;
  49     if (l < min)
  50         l = min;
  51
  52     n = pa_memblock_new(c->memblock->pool, l);
  53     memcpy(n->data, (uint8_t*) c->memblock->data + c->index, c->length);
  54     pa_memblock_unref(c->memblock);
  55     c->memblock = n;
  56     c->index = 0;
  57 }
  58
  59 void pa_memchunk_reset(pa_memchunk *c) {
  60     assert(c);
  61
  62     c->memblock = NULL;
  63     c->length = c->index = 0;
  64 }