LXR qemu/audio/noaudio.c

   1/*
   2 * QEMU Timer based audio emulation
   3 *
   4 * Copyright (c) 2004-2005 Vassili Karpov (malc)
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24#include "qemu/osdep.h"
  25#include "qemu-common.h"
  26#include "qemu/host-utils.h"
  27#include "audio.h"
  28#include "qemu/timer.h"
  29
  30#define AUDIO_CAP "noaudio"
  31#include "audio_int.h"
  32
  33typedef struct NoVoiceOut {
  34    HWVoiceOut hw;
  35    int64_t old_ticks;
  36} NoVoiceOut;
  37
  38typedef struct NoVoiceIn {
  39    HWVoiceIn hw;
  40    int64_t old_ticks;
  41} NoVoiceIn;
  42
  43static int no_run_out (HWVoiceOut *hw, int live)
  44{
  45    NoVoiceOut *no = (NoVoiceOut *) hw;
  46    int decr, samples;
  47    int64_t now;
  48    int64_t ticks;
  49    int64_t bytes;
  50
  51    now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
  52    ticks = now - no->old_ticks;
  53    bytes = muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND);
  54    bytes = audio_MIN(bytes, INT_MAX);
  55    samples = bytes >> hw->info.shift;
  56
  57    no->old_ticks = now;
  58    decr = audio_MIN (live, samples);
  59    hw->rpos = (hw->rpos + decr) % hw->samples;
  60    return decr;
  61}
  62
  63static int no_write (SWVoiceOut *sw, void *buf, int len)
  64{
  65    return audio_pcm_sw_write(sw, buf, len);
  66}
  67
  68static int no_init_out(HWVoiceOut *hw, struct audsettings *as, void *drv_opaque)
  69{
  70    audio_pcm_init_info (&hw->info, as);
  71    hw->samples = 1024;
  72    return 0;
  73}
  74
  75static void no_fini_out (HWVoiceOut *hw)
  76{
  77    (void) hw;
  78}
  79
  80static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
  81{
  82    (void) hw;
  83    (void) cmd;
  84    return 0;
  85}
  86
  87static int no_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
  88{
  89    audio_pcm_init_info (&hw->info, as);
  90    hw->samples = 1024;
  91    return 0;
  92}
  93
  94static void no_fini_in (HWVoiceIn *hw)
  95{
  96    (void) hw;
  97}
  98
  99static int no_run_in (HWVoiceIn *hw)
 100{
 101    NoVoiceIn *no = (NoVoiceIn *) hw;
 102    int live = audio_pcm_hw_get_live_in (hw);
 103    int dead = hw->samples - live;
 104    int samples = 0;
 105
 106    if (dead) {
 107        int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 108        int64_t ticks = now - no->old_ticks;
 109        int64_t bytes =
 110            muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND);
 111
 112        no->old_ticks = now;
 113        bytes = audio_MIN (bytes, INT_MAX);
 114        samples = bytes >> hw->info.shift;
 115        samples = audio_MIN (samples, dead);
 116    }
 117    return samples;
 118}
 119
 120static int no_read (SWVoiceIn *sw, void *buf, int size)
 121{
 122    /* use custom code here instead of audio_pcm_sw_read() to avoid
 123     * useless resampling/mixing */
 124    int samples = size >> sw->info.shift;
 125    int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired;
 126    int to_clear = audio_MIN (samples, total);
 127    sw->total_hw_samples_acquired += total;
 128    audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
 129    return to_clear << sw->info.shift;
 130}
 131
 132static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
 133{
 134    (void) hw;
 135    (void) cmd;
 136    return 0;
 137}
 138
 139static void *no_audio_init (void)
 140{
 141    return &no_audio_init;
 142}
 143
 144static void no_audio_fini (void *opaque)
 145{
 146    (void) opaque;
 147}
 148
 149static struct audio_pcm_ops no_pcm_ops = {
 150    .init_out = no_init_out,
 151    .fini_out = no_fini_out,
 152    .run_out  = no_run_out,
 153    .write    = no_write,
 154    .ctl_out  = no_ctl_out,
 155
 156    .init_in  = no_init_in,
 157    .fini_in  = no_fini_in,
 158    .run_in   = no_run_in,
 159    .read     = no_read,
 160    .ctl_in   = no_ctl_in
 161};
 162
 163struct audio_driver no_audio_driver = {
 164    .name           = "none",
 165    .descr          = "Timer based audio emulation",
 166    .options        = NULL,
 167    .init           = no_audio_init,
 168    .fini           = no_audio_fini,
 169    .pcm_ops        = &no_pcm_ops,
 170    .can_be_default = 1,
 171    .max_voices_out = INT_MAX,
 172    .max_voices_in  = INT_MAX,
 173    .voice_size_out = sizeof (NoVoiceOut),
 174    .voice_size_in  = sizeof (NoVoiceIn)
 175};
 176