code.delx.au - pulseaudio/blob - polyp/memchunk.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio 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   General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with polypaudio; 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 "memchunk.h"
  32 #include "xmalloc.h"
  33
  34 void pa_memchunk_make_writable(struct pa_memchunk *c, struct pa_memblock_stat *s) {
  35     struct pa_memblock *n;
  36     assert(c && c->memblock && c->memblock->ref >= 1);
  37
  38     if (c->memblock->ref == 1)
  39         return;
  40
  41     n = pa_memblock_new(c->length, s);
  42     assert(n);
  43     memcpy(n->data, (uint8_t*) c->memblock->data+c->index, c->length);
  44     pa_memblock_unref(c->memblock);
  45     c->memblock = n;
  46     c->index = 0;
  47 }
  48
  49
  50 struct pa_mcalign {
  51     size_t base;
  52     struct pa_memchunk chunk;
  53     uint8_t *buffer;
  54     size_t buffer_fill;
  55     struct pa_memblock_stat *memblock_stat;
  56 };
  57
  58 struct pa_mcalign *pa_mcalign_new(size_t base, struct pa_memblock_stat *s) {
  59     struct pa_mcalign *m;
  60     assert(base);
  61
  62     m = pa_xmalloc(sizeof(struct pa_mcalign));
  63     m->base = base;
  64     m->chunk.memblock = NULL;
  65     m->chunk.length = m->chunk.index = 0;
  66     m->buffer = NULL;
  67     m->buffer_fill = 0;
  68     m->memblock_stat = s;
  69     return m;
  70 }
  71
  72 void pa_mcalign_free(struct pa_mcalign *m) {
  73     assert(m);
  74
  75     pa_xfree(m->buffer);
  76
  77     if (m->chunk.memblock)
  78         pa_memblock_unref(m->chunk.memblock);
  79
  80     pa_xfree(m);
  81 }
  82
  83 void pa_mcalign_push(struct pa_mcalign *m, const struct pa_memchunk *c) {
  84     assert(m && c && !m->chunk.memblock && c->memblock && c->length);
  85
  86     m->chunk = *c;
  87     pa_memblock_ref(m->chunk.memblock);
  88 }
  89
  90 int pa_mcalign_pop(struct pa_mcalign *m, struct pa_memchunk *c) {
  91     int ret;
  92     assert(m && c && m->base > m->buffer_fill);
  93
  94     if (!m->chunk.memblock)
  95         return -1;
  96
  97     if (m->buffer_fill) {
  98         size_t l = m->base - m->buffer_fill;
  99         if (l > m->chunk.length)
 100             l = m->chunk.length;
 101         assert(m->buffer && l);
 102
 103         memcpy((uint8_t*) m->buffer + m->buffer_fill, (uint8_t*) m->chunk.memblock->data + m->chunk.index, l);
 104         m->buffer_fill += l;
 105         m->chunk.index += l;
 106         m->chunk.length -= l;
 107
 108         if (m->chunk.length == 0) {
 109             m->chunk.length = m->chunk.index = 0;
 110             pa_memblock_unref(m->chunk.memblock);
 111             m->chunk.memblock = NULL;
 112         }
 113
 114         assert(m->buffer_fill <= m->base);
 115         if (m->buffer_fill == m->base) {
 116             c->memblock = pa_memblock_new_dynamic(m->buffer, m->base, m->memblock_stat);
 117             assert(c->memblock);
 118             c->index = 0;
 119             c->length = m->base;
 120             m->buffer = NULL;
 121             m->buffer_fill = 0;
 122
 123             return 0;
 124         }
 125
 126         return -1;
 127     }
 128
 129     m->buffer_fill = m->chunk.length % m->base;
 130
 131     if (m->buffer_fill) {
 132         assert(!m->buffer);
 133         m->buffer = pa_xmalloc(m->base);
 134         m->chunk.length -= m->buffer_fill;
 135         memcpy(m->buffer, (uint8_t*) m->chunk.memblock->data + m->chunk.index + m->chunk.length, m->buffer_fill);
 136     }
 137
 138     if (m->chunk.length) {
 139         *c = m->chunk;
 140         pa_memblock_ref(c->memblock);
 141         ret = 0;
 142     } else
 143         ret = -1;
 144
 145     m->chunk.length = m->chunk.index = 0;
 146     pa_memblock_unref(m->chunk.memblock);
 147     m->chunk.memblock = NULL;
 148
 149     return ret;
 150 }