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 "vl.h"
  25
  26 #define AUDIO_CAP "noaudio"
  27 #include "audio_int.h"
  28
  29 typedef struct NoVoiceOut {
  30     HWVoiceOut hw;
  31     int64_t old_ticks;
  32 } NoVoiceOut;
  33
  34 typedef struct NoVoiceIn {
  35     HWVoiceIn hw;
  36     int64_t old_ticks;
  37 } NoVoiceIn;
  38
  39 static int no_run_out (HWVoiceOut *hw)
  40 {
  41     NoVoiceOut *no = (NoVoiceOut *) hw;
  42     int live, decr, samples;
  43     int64_t now;
  44     int64_t ticks;
  45     int64_t bytes;
  46
  47     live = audio_pcm_hw_get_live_out (&no->hw);
  48     if (!live) {
  49         return 0;
  50     }
  51
  52     now = qemu_get_clock (vm_clock);
  53     ticks = now - no->old_ticks;
  54     bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
  55     bytes = audio_MIN (bytes, INT_MAX);
  56     samples = bytes >> hw->info.shift;
  57
  58     no->old_ticks = now;
  59     decr = audio_MIN (live, samples);
  60     hw->rpos = (hw->rpos + decr) % hw->samples;
  61     return decr;
  62 }
  63
  64 static int no_write (SWVoiceOut *sw, void *buf, int len)
  65 {
  66     return audio_pcm_sw_write (sw, buf, len);
  67 }
  68
  69 static int no_init_out (HWVoiceOut *hw, audsettings_t *as)
  70 {
  71     audio_pcm_init_info (&hw->info, as);
  72     hw->samples = 1024;
  73     return 0;
  74 }
  75
  76 static void no_fini_out (HWVoiceOut *hw)
  77 {
  78     (void) hw;
  79 }
  80
  81 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
  82 {
  83     (void) hw;
  84     (void) cmd;
  85     return 0;
  86 }
  87
  88 static int no_init_in (HWVoiceIn *hw, audsettings_t *as)
  89 {
  90     audio_pcm_init_info (&hw->info, as);
  91     hw->samples = 1024;
  92     return 0;
  93 }
  94
  95 static void no_fini_in (HWVoiceIn *hw)
  96 {
  97     (void) hw;
  98 }
  99
 100 static int no_run_in (HWVoiceIn *hw)
 101 {
 102     NoVoiceIn *no = (NoVoiceIn *) hw;
 103     int live = audio_pcm_hw_get_live_in (hw);
 104     int dead = hw->samples - live;
 105     int samples = 0;
 106
 107     if (dead) {
 108         int64_t now = qemu_get_clock (vm_clock);
 109         int64_t ticks = now - no->old_ticks;
 110         int64_t bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
 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
 120 static int no_read (SWVoiceIn *sw, void *buf, int size)
 121 {
 122     int samples = size >> sw->info.shift;
 123     int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired;
 124     int to_clear = audio_MIN (samples, total);
 125     audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
 126     return to_clear;
 127 }
 128
 129 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
 130 {
 131     (void) hw;
 132     (void) cmd;
 133     return 0;
 134 }
 135
 136 static void *no_audio_init (void)
 137 {
 138     return &no_audio_init;
 139 }
 140
 141 static void no_audio_fini (void *opaque)
 142 {
 143     (void) opaque;
 144 }
 145
 146 static struct audio_pcm_ops no_pcm_ops = {
 147     no_init_out,
 148     no_fini_out,
 149     no_run_out,
 150     no_write,
 151     no_ctl_out,
 152
 153     no_init_in,
 154     no_fini_in,
 155     no_run_in,
 156     no_read,
 157     no_ctl_in
 158 };
 159
 160 struct audio_driver no_audio_driver = {
 161     INIT_FIELD (name           = ) "none",
 162     INIT_FIELD (descr          = ) "Timer based audio emulation",
 163     INIT_FIELD (options        = ) NULL,
 164     INIT_FIELD (init           = ) no_audio_init,
 165     INIT_FIELD (fini           = ) no_audio_fini,
 166     INIT_FIELD (pcm_ops        = ) &no_pcm_ops,
 167     INIT_FIELD (can_be_default = ) 1,
 168     INIT_FIELD (max_voices_out = ) INT_MAX,
 169     INIT_FIELD (max_voices_in  = ) INT_MAX,
 170     INIT_FIELD (voice_size_out = ) sizeof (NoVoiceOut),
 171     INIT_FIELD (voice_size_in  = ) sizeof (NoVoiceIn)
 172 };