/* * QEMU NULL audio output driver * * Copyright (c) 2004 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" #include "audio/audio_int.h" typedef struct NoVoice { HWVoice hw; int64_t old_ticks; } NoVoice; #define dolog(...) AUD_log ("noaudio", __VA_ARGS__) #ifdef DEBUG #define ldebug(...) dolog (__VA_ARGS__) #else #define ldebug(...) #endif static void no_hw_run (HWVoice *hw) { NoVoice *no = (NoVoice *) hw; int rpos, live, decr, samples; uint8_t *dst; st_sample_t *src; int64_t now = qemu_get_clock (vm_clock); int64_t ticks = now - no->old_ticks; int64_t bytes = (ticks * hw->bytes_per_second) / ticks_per_sec; if (bytes > INT_MAX) samples = INT_MAX >> hw->shift; else samples = bytes >> hw->shift; live = pcm_hw_get_live (hw); if (live <= 0) return; no->old_ticks = now; decr = audio_MIN (live, samples); samples = decr; rpos = hw->rpos; while (samples) { int left_till_end_samples = hw->samples - rpos; int convert_samples = audio_MIN (samples, left_till_end_samples); src = advance (hw->mix_buf, rpos * sizeof (st_sample_t)); memset (src, 0, convert_samples * sizeof (st_sample_t)); rpos = (rpos + convert_samples) % hw->samples; samples -= convert_samples; } pcm_hw_dec_live (hw, decr); hw->rpos = rpos; } static int no_hw_write (SWVoice *sw, void *buf, int len) { return pcm_hw_write (sw, buf, len); } static int no_hw_init (HWVoice *hw, int freq, int nchannels, audfmt_e fmt) { NoVoice *no = (NoVoice *) hw; hw->freq = freq; hw->nchannels = nchannels; hw->fmt = fmt; hw->bufsize = 4096; return 0; } static void no_hw_fini (HWVoice *hw) { (void) hw; } static int no_hw_ctl (HWVoice *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) { } struct pcm_ops no_pcm_ops = { no_hw_init, no_hw_fini, no_hw_run, no_hw_write, no_hw_ctl }; struct audio_output_driver no_output_driver = { "none", no_audio_init, no_audio_fini, &no_pcm_ops, 1, 1, sizeof (NoVoice) };