qemu/audio/noaudio.c

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/*
* QEMU Timer based audio emulation
*
* Copyright (c) 2004-2005 Vassili Karpov (malc)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "vl.h"
#define AUDIO_CAP "noaudio"
#include "audio_int.h"
typedef struct NoVoiceOut {
HWVoiceOut hw;
int64_t old_ticks;
} NoVoiceOut;
typedef struct NoVoiceIn {
HWVoiceIn hw;
int64_t old_ticks;
} NoVoiceIn;
static int no_run_out (HWVoiceOut *hw)
{
NoVoiceOut *no = (NoVoiceOut *) hw;
int live, decr, samples;
int64_t now = qemu_get_clock (vm_clock);
int64_t ticks = now - no->old_ticks;
int64_t bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
if (bytes > INT_MAX) {
samples = INT_MAX >> hw->info.shift;
}
else {
samples = bytes >> hw->info.shift;
}
live = audio_pcm_hw_get_live_out (&no->hw);
if (!live) {
return 0;
}
no->old_ticks = now;
decr = audio_MIN (live, samples);
hw->rpos = (hw->rpos + decr) % hw->samples;
return decr;
}
static int no_write (SWVoiceOut *sw, void *buf, int len)
{
return audio_pcm_sw_write (sw, buf, len);
}
static int no_init_out (HWVoiceOut *hw, audsettings_t *as)
{
audio_pcm_init_info (&hw->info, as, 0);
hw->samples = 1024;
return 0;
}
static void no_fini_out (HWVoiceOut *hw)
{
(void) hw;
}
static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
{
(void) hw;
(void) cmd;
return 0;
}
static int no_init_in (HWVoiceIn *hw, audsettings_t *as)
{
audio_pcm_init_info (&hw->info, as, 0);
hw->samples = 1024;
return 0;
}
static void no_fini_in (HWVoiceIn *hw)
{
(void) hw;
}
static int no_run_in (HWVoiceIn *hw)
{
NoVoiceIn *no = (NoVoiceIn *) hw;
int64_t now = qemu_get_clock (vm_clock);
int64_t ticks = now - no->old_ticks;
int64_t bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
int live = audio_pcm_hw_get_live_in (hw);
int dead = hw->samples - live;
int samples;
bytes = audio_MIN (bytes, INT_MAX);
samples = bytes >> hw->info.shift;
samples = audio_MIN (samples, dead);
return samples;
}
static int no_read (SWVoiceIn *sw, void *buf, int size)
{
int samples = size >> sw->info.shift;
int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired;
int to_clear = audio_MIN (samples, total);
audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
return to_clear;
}
static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
{
(void) hw;
(void) cmd;
return 0;
}
static void *no_audio_init (void)
{
return &no_audio_init;
}
static void no_audio_fini (void *opaque)
{
(void) opaque;
}
static struct audio_pcm_ops no_pcm_ops = {
no_init_out,
no_fini_out,
no_run_out,
no_write,
no_ctl_out,
no_init_in,
no_fini_in,
no_run_in,
no_read,
no_ctl_in
};
struct audio_driver no_audio_driver = {
INIT_FIELD (name = ) "none",
INIT_FIELD (descr = ) "Timer based audio emulation",
INIT_FIELD (options = ) NULL,
INIT_FIELD (init = ) no_audio_init,
INIT_FIELD (fini = ) no_audio_fini,
INIT_FIELD (pcm_ops = ) &no_pcm_ops,
INIT_FIELD (can_be_default = ) 1,
INIT_FIELD (max_voices_out = ) INT_MAX,
INIT_FIELD (max_voices_in = ) INT_MAX,
INIT_FIELD (voice_size_out = ) sizeof (NoVoiceOut),
INIT_FIELD (voice_size_in = ) sizeof (NoVoiceIn)
};