src/pulsecore/memchunk.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   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 <string.h>
  29 #include <errno.h>
  30
  31 #include <pulse/xmalloc.h>
  32 #include <pulsecore/macro.h>
  33 #include <pulsecore/core-util.h>
  34
  35 #include "memchunk.h"
  36
  37 pa_memchunk* pa_memchunk_make_writable(pa_memchunk *c, size_t min) {
  38     pa_memblock *n;
  39     size_t l;
  40     void *tdata, *sdata;
  41
  42     pa_assert(c);
  43     pa_assert(c->memblock);
  44
  45     if (pa_memblock_ref_is_one(c->memblock) &&
  46         !pa_memblock_is_read_only(c->memblock) &&
  47         pa_memblock_get_length(c->memblock) >= c->index+min)
  48         return c;
  49
  50     l = PA_MAX(c->length, min);
  51
  52     n = pa_memblock_new(pa_memblock_get_pool(c->memblock), l);
  53
  54     sdata = pa_memblock_acquire(c->memblock);
  55     tdata = pa_memblock_acquire(n);
  56
  57     memcpy(tdata, (uint8_t*) sdata + c->index, c->length);
  58
  59     pa_memblock_release(c->memblock);
  60     pa_memblock_release(n);
  61
  62     pa_memblock_unref(c->memblock);
  63
  64     c->memblock = n;
  65     c->index = 0;
  66
  67     return c;
  68 }
  69
  70 pa_memchunk* pa_memchunk_reset(pa_memchunk *c) {
  71     pa_assert(c);
  72
  73     memset(c, 0, sizeof(*c));
  74
  75     return c;
  76 }
  77
  78 pa_memchunk *pa_memchunk_will_need(const pa_memchunk *c) {
  79     void *p;
  80
  81     pa_assert(c);
  82     pa_assert(c->memblock);
  83
  84     /* A version of pa_memblock_will_need() that works on memchunks
  85      * instead of memblocks */
  86
  87     p = (uint8_t*) pa_memblock_acquire(c->memblock) + c->index;
  88     pa_will_need(p, c->length);
  89     pa_memblock_release(c->memblock);
  90
  91     return (pa_memchunk*) c;
  92 }
  93
  94 pa_memchunk* pa_memchunk_memcpy(pa_memchunk *dst, pa_memchunk *src) {
  95     void *p, *q;
  96
  97     pa_assert(dst);
  98     pa_assert(src);
  99     pa_assert(dst->length == src->length);
 100
 101     p = pa_memblock_acquire(dst->memblock);
 102     q = pa_memblock_acquire(src->memblock);
 103
 104     memmove((uint8_t*) p + dst->index,
 105             (uint8_t*) q + src->index,
 106             dst->length);
 107
 108     pa_memblock_release(dst->memblock);
 109     pa_memblock_release(src->memblock);
 110
 111     return dst;
 112 }