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-common.h"
  25 #include "audio.h"
  26 #include "qemu-timer.h"
  27
  28 #define AUDIO_CAP "noaudio"
  29 #include "audio_int.h"
  30
  31 typedef struct NoVoiceOut {
  32     HWVoiceOut hw;
  33     int64_t old_ticks;
  34 } NoVoiceOut;
  35
  36 typedef struct NoVoiceIn {
  37     HWVoiceIn hw;
  38     int64_t old_ticks;
  39 } NoVoiceIn;
  40
  41 static int no_run_out (HWVoiceOut *hw)
  42 {
  43     NoVoiceOut *no = (NoVoiceOut *) hw;
  44     int live, decr, samples;
  45     int64_t now;
  46     int64_t ticks;
  47     int64_t bytes;
  48
  49     live = audio_pcm_hw_get_live_out (&no->hw);
  50     if (!live) {
  51         return 0;
  52     }
  53
  54     now = qemu_get_clock (vm_clock);
  55     ticks = now - no->old_ticks;
  56     bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
  57     bytes = audio_MIN (bytes, INT_MAX);
  58     samples = bytes >> hw->info.shift;
  59
  60     no->old_ticks = now;
  61     decr = audio_MIN (live, samples);
  62     hw->rpos = (hw->rpos + decr) % hw->samples;
  63     return decr;
  64 }
  65
  66 static int no_write (SWVoiceOut *sw, void *buf, int len)
  67 {
  68     return audio_pcm_sw_write (sw, buf, len);
  69 }
  70
  71 static int no_init_out (HWVoiceOut *hw, struct audsettings *as)
  72 {
  73     audio_pcm_init_info (&hw->info, as);
  74     hw->samples = 1024;
  75     return 0;
  76 }
  77
  78 static void no_fini_out (HWVoiceOut *hw)
  79 {
  80     (void) hw;
  81 }
  82
  83 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
  84 {
  85     (void) hw;
  86     (void) cmd;
  87     return 0;
  88 }
  89
  90 static int no_init_in (HWVoiceIn *hw, struct audsettings *as)
  91 {
  92     audio_pcm_init_info (&hw->info, as);
  93     hw->samples = 1024;
  94     return 0;
  95 }
  96
  97 static void no_fini_in (HWVoiceIn *hw)
  98 {
  99     (void) hw;
 100 }
 101
 102 static int no_run_in (HWVoiceIn *hw)
 103 {
 104     NoVoiceIn *no = (NoVoiceIn *) hw;
 105     int live = audio_pcm_hw_get_live_in (hw);
 106     int dead = hw->samples - live;
 107     int samples = 0;
 108
 109     if (dead) {
 110         int64_t now = qemu_get_clock (vm_clock);
 111         int64_t ticks = now - no->old_ticks;
 112         int64_t bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
 113
 114         no->old_ticks = now;
 115         bytes = audio_MIN (bytes, INT_MAX);
 116         samples = bytes >> hw->info.shift;
 117         samples = audio_MIN (samples, dead);
 118     }
 119     return samples;
 120 }
 121
 122 static int no_read (SWVoiceIn *sw, void *buf, int size)
 123 {
 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     audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
 128     return to_clear;
 129 }
 130
 131 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
 132 {
 133     (void) hw;
 134     (void) cmd;
 135     return 0;
 136 }
 137
 138 static void *no_audio_init (void)
 139 {
 140     return &no_audio_init;
 141 }
 142
 143 static void no_audio_fini (void *opaque)
 144 {
 145     (void) opaque;
 146 }
 147
 148 static struct audio_pcm_ops no_pcm_ops = {
 149     .init_out = no_init_out,
 150     .fini_out = no_fini_out,
 151     .run_out  = no_run_out,
 152     .write    = no_write,
 153     .ctl_out  = no_ctl_out,
 154
 155     .init_in  = no_init_in,
 156     .fini_in  = no_fini_in,
 157     .run_in   = no_run_in,
 158     .read     = no_read,
 159     .ctl_in   = no_ctl_in
 160 };
 161
 162 struct audio_driver no_audio_driver = {
 163     .name           = "none",
 164     .descr          = "Timer based audio emulation",
 165     .options        = NULL,
 166     .init           = no_audio_init,
 167     .fini           = no_audio_fini,
 168     .pcm_ops        = &no_pcm_ops,
 169     .can_be_default = 1,
 170     .max_voices_out = INT_MAX,
 171     .max_voices_in  = INT_MAX,
 172     .voice_size_out = sizeof (NoVoiceOut),
 173     .voice_size_in  = sizeof (NoVoiceIn)
 174 };