audio/audio_template.h - qemu - Git at Google

 /*
  * QEMU Audio subsystem header
  *
  * Copyright (c) 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.
  */

 #ifdef DAC
 #define NAME "playback"
 #define HWBUF hw->mix_buf
 #define TYPE out
 #define HW HWVoiceOut
 #define SW SWVoiceOut
 #else
 #define NAME "capture"
 #define TYPE in
 #define HW HWVoiceIn
 #define SW SWVoiceIn
 #define HWBUF hw->conv_buf
 #endif

 static void glue(audio_init_nb_voices_, TYPE)(AudioState *s,
                                               struct audio_driver *drv, int min_voices)
 {
     int max_voices = glue (drv->max_voices_, TYPE);
     size_t voice_size = glue(drv->voice_size_, TYPE);

     glue (s->nb_hw_voices_, TYPE) = glue(audio_get_pdo_, TYPE)(s->dev)->voices;
     if (glue (s->nb_hw_voices_, TYPE) > max_voices) {
         if (!max_voices) {
 #ifdef DAC
             dolog ("Driver `%s' does not support " NAME "\n", drv->name);
 #endif
         } else {
             dolog ("Driver `%s' does not support %d " NAME " voices, max %d\n",
                    drv->name,
                    glue (s->nb_hw_voices_, TYPE),
                    max_voices);
         }
         glue (s->nb_hw_voices_, TYPE) = max_voices;
     }

     if (glue (s->nb_hw_voices_, TYPE) < min_voices) {
         dolog ("Bogus number of " NAME " voices %d, setting to %d\n",
                glue (s->nb_hw_voices_, TYPE),
                min_voices);
     }

     if (audio_bug(__func__, !voice_size && max_voices)) {
         dolog ("drv=`%s' voice_size=0 max_voices=%d\n",
                drv->name, max_voices);
         glue (s->nb_hw_voices_, TYPE) = 0;
     }

     if (audio_bug(__func__, voice_size && !max_voices)) {
         dolog("drv=`%s' voice_size=%zu max_voices=0\n",
               drv->name, voice_size);
     }
 }

 static void glue (audio_pcm_hw_free_resources_, TYPE) (HW *hw)
 {
     g_free(hw->buf_emul);
     g_free(HWBUF.buffer);
     HWBUF.buffer = NULL;
     HWBUF.size = 0;
 }

 static void glue(audio_pcm_hw_alloc_resources_, TYPE)(HW *hw)
 {
     if (glue(audio_get_pdo_, TYPE)(hw->s->dev)->mixing_engine) {
         size_t samples = hw->samples;
         if (audio_bug(__func__, samples == 0)) {
             dolog("Attempted to allocate empty buffer\n");
         }

         HWBUF.buffer = g_new0(st_sample, samples);
         HWBUF.size = samples;
         HWBUF.pos = 0;
     } else {
         HWBUF.buffer = NULL;
         HWBUF.size = 0;
     }
 }

 static void glue (audio_pcm_sw_free_resources_, TYPE) (SW *sw)
 {
     g_free(sw->resample_buf.buffer);
     sw->resample_buf.buffer = NULL;
     sw->resample_buf.size = 0;

     if (sw->rate) {
         st_rate_stop (sw->rate);
     }
     sw->rate = NULL;
 }

 static int glue (audio_pcm_sw_alloc_resources_, TYPE) (SW *sw)
 {
     HW *hw = sw->hw;
     uint64_t samples;

     if (!glue(audio_get_pdo_, TYPE)(sw->s->dev)->mixing_engine) {
         return 0;
     }

     samples = muldiv64(HWBUF.size, sw->info.freq, hw->info.freq);
     if (samples == 0) {
         uint64_t f_fe_min;
         uint64_t f_be = (uint32_t)hw->info.freq;

         /* f_fe_min = ceil(1 [frames] * f_be [Hz] / size_be [frames]) */
         f_fe_min = (f_be + HWBUF.size - 1) / HWBUF.size;
         qemu_log_mask(LOG_UNIMP,
                       AUDIO_CAP ": The guest selected a " NAME " sample rate"
                       " of %d Hz for %s. Only sample rates >= %" PRIu64 " Hz"
                       " are supported.\n",
                       sw->info.freq, sw->name, f_fe_min);
         return -1;
     }

     /*
      * Allocate one additional audio frame that is needed for upsampling
      * if the resample buffer size is small. For large buffer sizes take
      * care of overflows and truncation.
      */
     samples = samples < SIZE_MAX ? samples + 1 : SIZE_MAX;
     sw->resample_buf.buffer = g_new0(st_sample, samples);
     sw->resample_buf.size = samples;
     sw->resample_buf.pos = 0;

 #ifdef DAC
     sw->rate = st_rate_start(sw->info.freq, hw->info.freq);
 #else
     sw->rate = st_rate_start(hw->info.freq, sw->info.freq);
 #endif

     return 0;
 }

 static int glue (audio_pcm_sw_init_, TYPE) (
     SW *sw,
     HW *hw,
     const char *name,
     struct audsettings *as
     )
 {
     int err;

     audio_pcm_init_info (&sw->info, as);
     sw->hw = hw;
     sw->active = 0;
 #ifdef DAC
     sw->total_hw_samples_mixed = 0;
     sw->empty = 1;
 #endif

     if (sw->info.is_float) {
 #ifdef DAC
         sw->conv = mixeng_conv_float[sw->info.nchannels == 2];
 #else
         sw->clip = mixeng_clip_float[sw->info.nchannels == 2];
 #endif
     } else {
 #ifdef DAC
         sw->conv = mixeng_conv
 #else
         sw->clip = mixeng_clip
 #endif
             [sw->info.nchannels == 2]
             [sw->info.is_signed]
             [sw->info.swap_endianness]
             [audio_bits_to_index(sw->info.bits)];
     }

     sw->name = g_strdup (name);
     err = glue (audio_pcm_sw_alloc_resources_, TYPE) (sw);
     if (err) {
         g_free (sw->name);
         sw->name = NULL;
     }
     return err;
 }

 static void glue (audio_pcm_sw_fini_, TYPE) (SW *sw)
 {
     glue (audio_pcm_sw_free_resources_, TYPE) (sw);
     g_free (sw->name);
     sw->name = NULL;
 }

 static void glue (audio_pcm_hw_add_sw_, TYPE) (HW *hw, SW *sw)
 {
     QLIST_INSERT_HEAD (&hw->sw_head, sw, entries);
 }

 static void glue (audio_pcm_hw_del_sw_, TYPE) (SW *sw)
 {
     QLIST_REMOVE (sw, entries);
 }

 static void glue (audio_pcm_hw_gc_, TYPE) (HW **hwp)
 {
     HW *hw = *hwp;
     AudioState *s = hw->s;

     if (!hw->sw_head.lh_first) {
 #ifdef DAC
         audio_detach_capture(hw);
 #endif
         QLIST_REMOVE(hw, entries);
         glue(hw->pcm_ops->fini_, TYPE) (hw);
         glue(s->nb_hw_voices_, TYPE) += 1;
         glue(audio_pcm_hw_free_resources_ , TYPE) (hw);
         g_free(hw);
         *hwp = NULL;
     }
 }

 static HW *glue(audio_pcm_hw_find_any_, TYPE)(AudioState *s, HW *hw)
 {
     return hw ? hw->entries.le_next : glue (s->hw_head_, TYPE).lh_first;
 }

 static HW *glue(audio_pcm_hw_find_any_enabled_, TYPE)(AudioState *s, HW *hw)
 {
     while ((hw = glue(audio_pcm_hw_find_any_, TYPE)(s, hw))) {
         if (hw->enabled) {
             return hw;
         }
     }
     return NULL;
 }

 static HW *glue(audio_pcm_hw_find_specific_, TYPE)(AudioState *s, HW *hw,
                                                    struct audsettings *as)
 {
     while ((hw = glue(audio_pcm_hw_find_any_, TYPE)(s, hw))) {
         if (audio_pcm_info_eq (&hw->info, as)) {
             return hw;
         }
     }
     return NULL;
 }

 static HW *glue(audio_pcm_hw_add_new_, TYPE)(AudioState *s,
                                              struct audsettings *as)
 {
     HW *hw;
     struct audio_driver *drv = s->drv;

     if (!glue (s->nb_hw_voices_, TYPE)) {
         return NULL;
     }

     if (audio_bug(__func__, !drv)) {
         dolog ("No host audio driver\n");
         return NULL;
     }

     if (audio_bug(__func__, !drv->pcm_ops)) {
         dolog ("Host audio driver without pcm_ops\n");
         return NULL;
     }

     /*
      * Since glue(s->nb_hw_voices_, TYPE) is != 0, glue(drv->voice_size_, TYPE)
      * is guaranteed to be != 0. See the audio_init_nb_voices_* functions.
      */
     hw = g_malloc0(glue(drv->voice_size_, TYPE));
     hw->s = s;
     hw->pcm_ops = drv->pcm_ops;

     QLIST_INIT (&hw->sw_head);
 #ifdef DAC
     QLIST_INIT (&hw->cap_head);
 #endif
     if (glue (hw->pcm_ops->init_, TYPE) (hw, as, s->drv_opaque)) {
         goto err0;
     }

     if (audio_bug(__func__, hw->samples <= 0)) {
         dolog("hw->samples=%zd\n", hw->samples);
         goto err1;
     }

     if (hw->info.is_float) {
 #ifdef DAC
         hw->clip = mixeng_clip_float[hw->info.nchannels == 2];
 #else
         hw->conv = mixeng_conv_float[hw->info.nchannels == 2];
 #endif
     } else {
 #ifdef DAC
         hw->clip = mixeng_clip
 #else
         hw->conv = mixeng_conv
 #endif
             [hw->info.nchannels == 2]
             [hw->info.is_signed]
             [hw->info.swap_endianness]
             [audio_bits_to_index(hw->info.bits)];
     }

     glue(audio_pcm_hw_alloc_resources_, TYPE)(hw);

     QLIST_INSERT_HEAD (&s->glue (hw_head_, TYPE), hw, entries);
     glue (s->nb_hw_voices_, TYPE) -= 1;
 #ifdef DAC
     audio_attach_capture (hw);
 #endif
     return hw;

  err1:
     glue (hw->pcm_ops->fini_, TYPE) (hw);
  err0:
     g_free (hw);
     return NULL;
 }

 AudiodevPerDirectionOptions *glue(audio_get_pdo_, TYPE)(Audiodev *dev)
 {
     switch (dev->driver) {
     case AUDIODEV_DRIVER_NONE:
         return dev->u.none.TYPE;
 #ifdef CONFIG_AUDIO_ALSA
     case AUDIODEV_DRIVER_ALSA:
         return qapi_AudiodevAlsaPerDirectionOptions_base(dev->u.alsa.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_COREAUDIO
     case AUDIODEV_DRIVER_COREAUDIO:
         return qapi_AudiodevCoreaudioPerDirectionOptions_base(
             dev->u.coreaudio.TYPE);
 #endif
 #ifdef CONFIG_DBUS_DISPLAY
     case AUDIODEV_DRIVER_DBUS:
         return dev->u.dbus.TYPE;
 #endif
 #ifdef CONFIG_AUDIO_DSOUND
     case AUDIODEV_DRIVER_DSOUND:
         return dev->u.dsound.TYPE;
 #endif
 #ifdef CONFIG_AUDIO_JACK
     case AUDIODEV_DRIVER_JACK:
         return qapi_AudiodevJackPerDirectionOptions_base(dev->u.jack.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_OSS
     case AUDIODEV_DRIVER_OSS:
         return qapi_AudiodevOssPerDirectionOptions_base(dev->u.oss.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_PA
     case AUDIODEV_DRIVER_PA:
         return qapi_AudiodevPaPerDirectionOptions_base(dev->u.pa.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_PIPEWIRE
     case AUDIODEV_DRIVER_PIPEWIRE:
         return qapi_AudiodevPipewirePerDirectionOptions_base(dev->u.pipewire.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_SDL
     case AUDIODEV_DRIVER_SDL:
         return qapi_AudiodevSdlPerDirectionOptions_base(dev->u.sdl.TYPE);
 #endif
 #ifdef CONFIG_AUDIO_SNDIO
     case AUDIODEV_DRIVER_SNDIO:
         return dev->u.sndio.TYPE;
 #endif
 #ifdef CONFIG_SPICE
     case AUDIODEV_DRIVER_SPICE:
         return dev->u.spice.TYPE;
 #endif
     case AUDIODEV_DRIVER_WAV:
         return dev->u.wav.TYPE;

     case AUDIODEV_DRIVER__MAX:
         break;
     }
     abort();
 }

 static HW *glue(audio_pcm_hw_add_, TYPE)(AudioState *s, struct audsettings *as)
 {
     HW *hw;
     AudiodevPerDirectionOptions *pdo = glue(audio_get_pdo_, TYPE)(s->dev);

     if (!pdo->mixing_engine || pdo->fixed_settings) {
         hw = glue(audio_pcm_hw_add_new_, TYPE)(s, as);
         if (!pdo->mixing_engine || hw) {
             return hw;
         }
     }

     hw = glue(audio_pcm_hw_find_specific_, TYPE)(s, NULL, as);
     if (hw) {
         return hw;
     }

     hw = glue(audio_pcm_hw_add_new_, TYPE)(s, as);
     if (hw) {
         return hw;
     }

     return glue(audio_pcm_hw_find_any_, TYPE)(s, NULL);
 }

 static SW *glue(audio_pcm_create_voice_pair_, TYPE)(
     AudioState *s,
     const char *sw_name,
     struct audsettings *as
     )
 {
     SW *sw;
     HW *hw;
     struct audsettings hw_as;
     AudiodevPerDirectionOptions *pdo = glue(audio_get_pdo_, TYPE)(s->dev);

     if (pdo->fixed_settings) {
         hw_as = audiodev_to_audsettings(pdo);
     } else {
         hw_as = *as;
     }

     sw = g_new0(SW, 1);
     sw->s = s;

     hw = glue(audio_pcm_hw_add_, TYPE)(s, &hw_as);
     if (!hw) {
         dolog("Could not create a backend for voice `%s'\n", sw_name);
         goto err1;
     }

     glue (audio_pcm_hw_add_sw_, TYPE) (hw, sw);

     if (glue (audio_pcm_sw_init_, TYPE) (sw, hw, sw_name, as)) {
         goto err2;
     }

     return sw;

 err2:
     glue (audio_pcm_hw_del_sw_, TYPE) (sw);
     glue (audio_pcm_hw_gc_, TYPE) (&hw);
 err1:
     g_free(sw);
     return NULL;
 }

 static void glue (audio_close_, TYPE) (SW *sw)
 {
     glue (audio_pcm_sw_fini_, TYPE) (sw);
     glue (audio_pcm_hw_del_sw_, TYPE) (sw);
     glue (audio_pcm_hw_gc_, TYPE) (&sw->hw);
     g_free (sw);
 }

 void glue (AUD_close_, TYPE) (QEMUSoundCard *card, SW *sw)
 {
     if (sw) {
         if (audio_bug(__func__, !card)) {
             dolog ("card=%p\n", card);
             return;
         }

         glue (audio_close_, TYPE) (sw);
     }
 }

 SW *glue (AUD_open_, TYPE) (
     QEMUSoundCard *card,
     SW *sw,
     const char *name,
     void *callback_opaque ,
     audio_callback_fn callback_fn,
     struct audsettings *as
     )
 {
     AudioState *s;
     AudiodevPerDirectionOptions *pdo;

     if (audio_bug(__func__, !card || !name || !callback_fn || !as)) {
         dolog ("card=%p name=%p callback_fn=%p as=%p\n",
                card, name, callback_fn, as);
         goto fail;
     }

     s = card->state;
     pdo = glue(audio_get_pdo_, TYPE)(s->dev);

     ldebug ("open %s, freq %d, nchannels %d, fmt %d\n",
             name, as->freq, as->nchannels, as->fmt);

     if (audio_bug(__func__, audio_validate_settings(as))) {
         audio_print_settings (as);
         goto fail;
     }

     if (audio_bug(__func__, !s->drv)) {
         dolog ("Can not open `%s' (no host audio driver)\n", name);
         goto fail;
     }

     if (sw && audio_pcm_info_eq (&sw->info, as)) {
         return sw;
     }

     if (!pdo->fixed_settings && sw) {
         glue (AUD_close_, TYPE) (card, sw);
         sw = NULL;
     }

     if (sw) {
         HW *hw = sw->hw;

         if (!hw) {
             dolog("Internal logic error: voice `%s' has no backend\n",
                   SW_NAME(sw));
             goto fail;
         }

         glue (audio_pcm_sw_fini_, TYPE) (sw);
         if (glue (audio_pcm_sw_init_, TYPE) (sw, hw, name, as)) {
             goto fail;
         }
     } else {
         sw = glue(audio_pcm_create_voice_pair_, TYPE)(s, name, as);
         if (!sw) {
             return NULL;
         }
     }

     sw->card = card;
     sw->vol = nominal_volume;
     sw->callback.fn = callback_fn;
     sw->callback.opaque = callback_opaque;

 #ifdef DEBUG_AUDIO
     dolog ("%s\n", name);
     audio_pcm_print_info ("hw", &sw->hw->info);
     audio_pcm_print_info ("sw", &sw->info);
 #endif

     return sw;

  fail:
     glue (AUD_close_, TYPE) (card, sw);
     return NULL;
 }

 int glue (AUD_is_active_, TYPE) (SW *sw)
 {
     return sw ? sw->active : 0;
 }

 void glue (AUD_init_time_stamp_, TYPE) (SW *sw, QEMUAudioTimeStamp *ts)
 {
     if (!sw) {
         return;
     }

     ts->old_ts = sw->hw->ts_helper;
 }

 uint64_t glue (AUD_get_elapsed_usec_, TYPE) (SW *sw, QEMUAudioTimeStamp *ts)
 {
     uint64_t delta, cur_ts, old_ts;

     if (!sw) {
         return 0;
     }

     cur_ts = sw->hw->ts_helper;
     old_ts = ts->old_ts;
     /* dolog ("cur %" PRId64 " old %" PRId64 "\n", cur_ts, old_ts); */

     if (cur_ts >= old_ts) {
         delta = cur_ts - old_ts;
     } else {
         delta = UINT64_MAX - old_ts + cur_ts;
     }

     if (!delta) {
         return 0;
     }

     return muldiv64 (delta, sw->hw->info.freq, 1000000);
 }

 #undef TYPE
 #undef HW
 #undef SW
 #undef HWBUF
 #undef NAME
	/*
	* QEMU Audio subsystem header
	*
	* Copyright (c) 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.
	*/

	#ifdef DAC
	#define NAME "playback"
	#define HWBUF hw->mix_buf
	#define TYPE out
	#define HW HWVoiceOut
	#define SW SWVoiceOut
	#else
	#define NAME "capture"
	#define TYPE in
	#define HW HWVoiceIn
	#define SW SWVoiceIn
	#define HWBUF hw->conv_buf
	#endif

	static void glue(audio_init_nb_voices_, TYPE)(AudioState *s,
	struct audio_driver *drv, int min_voices)
	{
	int max_voices = glue (drv->max_voices_, TYPE);
	size_t voice_size = glue(drv->voice_size_, TYPE);

	glue (s->nb_hw_voices_, TYPE) = glue(audio_get_pdo_, TYPE)(s->dev)->voices;
	if (glue (s->nb_hw_voices_, TYPE) > max_voices) {
	if (!max_voices) {
	#ifdef DAC
	dolog ("Driver `%s' does not support " NAME "\n", drv->name);
	#endif
	} else {
	dolog ("Driver `%s' does not support %d " NAME " voices, max %d\n",
	drv->name,
	glue (s->nb_hw_voices_, TYPE),
	max_voices);
	}
	glue (s->nb_hw_voices_, TYPE) = max_voices;
	}

	if (glue (s->nb_hw_voices_, TYPE) < min_voices) {
	dolog ("Bogus number of " NAME " voices %d, setting to %d\n",
	glue (s->nb_hw_voices_, TYPE),
	min_voices);
	}

	if (audio_bug(__func__, !voice_size && max_voices)) {
	dolog ("drv=`%s' voice_size=0 max_voices=%d\n",
	drv->name, max_voices);
	glue (s->nb_hw_voices_, TYPE) = 0;
	}

	if (audio_bug(__func__, voice_size && !max_voices)) {
	dolog("drv=`%s' voice_size=%zu max_voices=0\n",
	drv->name, voice_size);
	}
	}

	static void glue (audio_pcm_hw_free_resources_, TYPE) (HW *hw)
	{
	g_free(hw->buf_emul);
	g_free(HWBUF.buffer);
	HWBUF.buffer = NULL;
	HWBUF.size = 0;
	}

	static void glue(audio_pcm_hw_alloc_resources_, TYPE)(HW *hw)
	{
	if (glue(audio_get_pdo_, TYPE)(hw->s->dev)->mixing_engine) {
	size_t samples = hw->samples;
	if (audio_bug(__func__, samples == 0)) {
	dolog("Attempted to allocate empty buffer\n");
	}

	HWBUF.buffer = g_new0(st_sample, samples);
	HWBUF.size = samples;
	HWBUF.pos = 0;
	} else {
	HWBUF.buffer = NULL;
	HWBUF.size = 0;
	}
	}

	static void glue (audio_pcm_sw_free_resources_, TYPE) (SW *sw)
	{
	g_free(sw->resample_buf.buffer);
	sw->resample_buf.buffer = NULL;
	sw->resample_buf.size = 0;

	if (sw->rate) {
	st_rate_stop (sw->rate);
	}
	sw->rate = NULL;
	}

	static int glue (audio_pcm_sw_alloc_resources_, TYPE) (SW *sw)
	{
	HW *hw = sw->hw;
	uint64_t samples;

	if (!glue(audio_get_pdo_, TYPE)(sw->s->dev)->mixing_engine) {
	return 0;
	}

	samples = muldiv64(HWBUF.size, sw->info.freq, hw->info.freq);
	if (samples == 0) {
	uint64_t f_fe_min;
	uint64_t f_be = (uint32_t)hw->info.freq;

	/* f_fe_min = ceil(1 [frames] * f_be [Hz] / size_be [frames]) */
	f_fe_min = (f_be + HWBUF.size - 1) / HWBUF.size;
	qemu_log_mask(LOG_UNIMP,
	AUDIO_CAP ": The guest selected a " NAME " sample rate"
	" of %d Hz for %s. Only sample rates >= %" PRIu64 " Hz"
	" are supported.\n",
	sw->info.freq, sw->name, f_fe_min);
	return -1;
	}

	/*
	* Allocate one additional audio frame that is needed for upsampling
	* if the resample buffer size is small. For large buffer sizes take
	* care of overflows and truncation.
	*/
	samples = samples < SIZE_MAX ? samples + 1 : SIZE_MAX;
	sw->resample_buf.buffer = g_new0(st_sample, samples);
	sw->resample_buf.size = samples;
	sw->resample_buf.pos = 0;

	#ifdef DAC
	sw->rate = st_rate_start(sw->info.freq, hw->info.freq);
	#else
	sw->rate = st_rate_start(hw->info.freq, sw->info.freq);
	#endif

	return 0;
	}

	static int glue (audio_pcm_sw_init_, TYPE) (
	SW *sw,
	HW *hw,
	const char *name,
	struct audsettings *as
	)
	{
	int err;

	audio_pcm_init_info (&sw->info, as);
	sw->hw = hw;
	sw->active = 0;
	#ifdef DAC
	sw->total_hw_samples_mixed = 0;
	sw->empty = 1;
	#endif

	if (sw->info.is_float) {
	#ifdef DAC
	sw->conv = mixeng_conv_float[sw->info.nchannels == 2];
	#else
	sw->clip = mixeng_clip_float[sw->info.nchannels == 2];
	#endif
	} else {
	#ifdef DAC
	sw->conv = mixeng_conv
	#else
	sw->clip = mixeng_clip
	#endif
	[sw->info.nchannels == 2]
	[sw->info.is_signed]
	[sw->info.swap_endianness]
	[audio_bits_to_index(sw->info.bits)];
	}

	sw->name = g_strdup (name);
	err = glue (audio_pcm_sw_alloc_resources_, TYPE) (sw);
	if (err) {
	g_free (sw->name);
	sw->name = NULL;
	}
	return err;
	}

	static void glue (audio_pcm_sw_fini_, TYPE) (SW *sw)
	{
	glue (audio_pcm_sw_free_resources_, TYPE) (sw);
	g_free (sw->name);
	sw->name = NULL;
	}

	static void glue (audio_pcm_hw_add_sw_, TYPE) (HW hw, SW sw)
	{
	QLIST_INSERT_HEAD (&hw->sw_head, sw, entries);
	}

	static void glue (audio_pcm_hw_del_sw_, TYPE) (SW *sw)
	{
	QLIST_REMOVE (sw, entries);
	}

	static void glue (audio_pcm_hw_gc_, TYPE) (HW **hwp)
	{
	HW hw = hwp;
	AudioState *s = hw->s;

	if (!hw->sw_head.lh_first) {
	#ifdef DAC
	audio_detach_capture(hw);
	#endif
	QLIST_REMOVE(hw, entries);
	glue(hw->pcm_ops->fini_, TYPE) (hw);
	glue(s->nb_hw_voices_, TYPE) += 1;
	glue(audio_pcm_hw_free_resources_ , TYPE) (hw);
	g_free(hw);
	*hwp = NULL;
	}
	}

	static HW glue(audio_pcm_hw_find_any_, TYPE)(AudioState s, HW *hw)
	{
	return hw ? hw->entries.le_next : glue (s->hw_head_, TYPE).lh_first;
	}

	static HW glue(audio_pcm_hw_find_any_enabled_, TYPE)(AudioState s, HW *hw)
	{
	while ((hw = glue(audio_pcm_hw_find_any_, TYPE)(s, hw))) {
	if (hw->enabled) {
	return hw;
	}
	}
	return NULL;
	}

	static HW glue(audio_pcm_hw_find_specific_, TYPE)(AudioState s, HW *hw,
	struct audsettings *as)
	{
	while ((hw = glue(audio_pcm_hw_find_any_, TYPE)(s, hw))) {
	if (audio_pcm_info_eq (&hw->info, as)) {
	return hw;
	}
	}
	return NULL;
	}

	static HW glue(audio_pcm_hw_add_new_, TYPE)(AudioState s,
	struct audsettings *as)
	{
	HW *hw;
	struct audio_driver *drv = s->drv;

	if (!glue (s->nb_hw_voices_, TYPE)) {
	return NULL;
	}

	if (audio_bug(__func__, !drv)) {
	dolog ("No host audio driver\n");
	return NULL;
	}

	if (audio_bug(__func__, !drv->pcm_ops)) {
	dolog ("Host audio driver without pcm_ops\n");
	return NULL;
	}

	/*
	* Since glue(s->nb_hw_voices_, TYPE) is != 0, glue(drv->voice_size_, TYPE)
	* is guaranteed to be != 0. See the audio_init_nb_voices_* functions.
	*/
	hw = g_malloc0(glue(drv->voice_size_, TYPE));
	hw->s = s;
	hw->pcm_ops = drv->pcm_ops;

	QLIST_INIT (&hw->sw_head);
	#ifdef DAC
	QLIST_INIT (&hw->cap_head);
	#endif
	if (glue (hw->pcm_ops->init_, TYPE) (hw, as, s->drv_opaque)) {
	goto err0;
	}

	if (audio_bug(__func__, hw->samples <= 0)) {
	dolog("hw->samples=%zd\n", hw->samples);
	goto err1;
	}

	if (hw->info.is_float) {
	#ifdef DAC
	hw->clip = mixeng_clip_float[hw->info.nchannels == 2];
	#else
	hw->conv = mixeng_conv_float[hw->info.nchannels == 2];
	#endif
	} else {
	#ifdef DAC
	hw->clip = mixeng_clip
	#else
	hw->conv = mixeng_conv
	#endif
	[hw->info.nchannels == 2]
	[hw->info.is_signed]
	[hw->info.swap_endianness]
	[audio_bits_to_index(hw->info.bits)];
	}

	glue(audio_pcm_hw_alloc_resources_, TYPE)(hw);

	QLIST_INSERT_HEAD (&s->glue (hw_head_, TYPE), hw, entries);
	glue (s->nb_hw_voices_, TYPE) -= 1;
	#ifdef DAC
	audio_attach_capture (hw);
	#endif
	return hw;

	err1:
	glue (hw->pcm_ops->fini_, TYPE) (hw);
	err0:
	g_free (hw);
	return NULL;
	}

	AudiodevPerDirectionOptions glue(audio_get_pdo_, TYPE)(Audiodev dev)
	{
	switch (dev->driver) {
	case AUDIODEV_DRIVER_NONE:
	return dev->u.none.TYPE;
	#ifdef CONFIG_AUDIO_ALSA
	case AUDIODEV_DRIVER_ALSA:
	return qapi_AudiodevAlsaPerDirectionOptions_base(dev->u.alsa.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_COREAUDIO
	case AUDIODEV_DRIVER_COREAUDIO:
	return qapi_AudiodevCoreaudioPerDirectionOptions_base(
	dev->u.coreaudio.TYPE);
	#endif
	#ifdef CONFIG_DBUS_DISPLAY
	case AUDIODEV_DRIVER_DBUS:
	return dev->u.dbus.TYPE;
	#endif
	#ifdef CONFIG_AUDIO_DSOUND
	case AUDIODEV_DRIVER_DSOUND:
	return dev->u.dsound.TYPE;
	#endif
	#ifdef CONFIG_AUDIO_JACK
	case AUDIODEV_DRIVER_JACK:
	return qapi_AudiodevJackPerDirectionOptions_base(dev->u.jack.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_OSS
	case AUDIODEV_DRIVER_OSS:
	return qapi_AudiodevOssPerDirectionOptions_base(dev->u.oss.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_PA
	case AUDIODEV_DRIVER_PA:
	return qapi_AudiodevPaPerDirectionOptions_base(dev->u.pa.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_PIPEWIRE
	case AUDIODEV_DRIVER_PIPEWIRE:
	return qapi_AudiodevPipewirePerDirectionOptions_base(dev->u.pipewire.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_SDL
	case AUDIODEV_DRIVER_SDL:
	return qapi_AudiodevSdlPerDirectionOptions_base(dev->u.sdl.TYPE);
	#endif
	#ifdef CONFIG_AUDIO_SNDIO
	case AUDIODEV_DRIVER_SNDIO:
	return dev->u.sndio.TYPE;
	#endif
	#ifdef CONFIG_SPICE
	case AUDIODEV_DRIVER_SPICE:
	return dev->u.spice.TYPE;
	#endif
	case AUDIODEV_DRIVER_WAV:
	return dev->u.wav.TYPE;

	case AUDIODEV_DRIVER__MAX:
	break;
	}
	abort();
	}

	static HW glue(audio_pcm_hw_add_, TYPE)(AudioState s, struct audsettings *as)
	{
	HW *hw;
	AudiodevPerDirectionOptions *pdo = glue(audio_get_pdo_, TYPE)(s->dev);

	if (!pdo->mixing_engine \|\| pdo->fixed_settings) {
	hw = glue(audio_pcm_hw_add_new_, TYPE)(s, as);
	if (!pdo->mixing_engine \|\| hw) {
	return hw;
	}
	}

	hw = glue(audio_pcm_hw_find_specific_, TYPE)(s, NULL, as);
	if (hw) {
	return hw;
	}

	hw = glue(audio_pcm_hw_add_new_, TYPE)(s, as);
	if (hw) {
	return hw;
	}

	return glue(audio_pcm_hw_find_any_, TYPE)(s, NULL);
	}

	static SW *glue(audio_pcm_create_voice_pair_, TYPE)(
	AudioState *s,
	const char *sw_name,
	struct audsettings *as
	)
	{
	SW *sw;
	HW *hw;
	struct audsettings hw_as;
	AudiodevPerDirectionOptions *pdo = glue(audio_get_pdo_, TYPE)(s->dev);

	if (pdo->fixed_settings) {
	hw_as = audiodev_to_audsettings(pdo);
	} else {
	hw_as = *as;
	}

	sw = g_new0(SW, 1);
	sw->s = s;

	hw = glue(audio_pcm_hw_add_, TYPE)(s, &hw_as);
	if (!hw) {
	dolog("Could not create a backend for voice `%s'\n", sw_name);
	goto err1;
	}

	glue (audio_pcm_hw_add_sw_, TYPE) (hw, sw);

	if (glue (audio_pcm_sw_init_, TYPE) (sw, hw, sw_name, as)) {
	goto err2;
	}

	return sw;

	err2:
	glue (audio_pcm_hw_del_sw_, TYPE) (sw);
	glue (audio_pcm_hw_gc_, TYPE) (&hw);
	err1:
	g_free(sw);
	return NULL;
	}

	static void glue (audio_close_, TYPE) (SW *sw)
	{
	glue (audio_pcm_sw_fini_, TYPE) (sw);
	glue (audio_pcm_hw_del_sw_, TYPE) (sw);
	glue (audio_pcm_hw_gc_, TYPE) (&sw->hw);
	g_free (sw);
	}

	void glue (AUD_close_, TYPE) (QEMUSoundCard card, SW sw)
	{
	if (sw) {
	if (audio_bug(__func__, !card)) {
	dolog ("card=%p\n", card);
	return;
	}

	glue (audio_close_, TYPE) (sw);
	}
	}

	SW *glue (AUD_open_, TYPE) (
	QEMUSoundCard *card,
	SW *sw,
	const char *name,
	void *callback_opaque ,
	audio_callback_fn callback_fn,
	struct audsettings *as
	)
	{
	AudioState *s;
	AudiodevPerDirectionOptions *pdo;

	if (audio_bug(__func__, !card \|\| !name \|\| !callback_fn \|\| !as)) {
	dolog ("card=%p name=%p callback_fn=%p as=%p\n",
	card, name, callback_fn, as);
	goto fail;
	}

	s = card->state;
	pdo = glue(audio_get_pdo_, TYPE)(s->dev);

	ldebug ("open %s, freq %d, nchannels %d, fmt %d\n",
	name, as->freq, as->nchannels, as->fmt);

	if (audio_bug(__func__, audio_validate_settings(as))) {
	audio_print_settings (as);
	goto fail;
	}

	if (audio_bug(__func__, !s->drv)) {
	dolog ("Can not open `%s' (no host audio driver)\n", name);
	goto fail;
	}

	if (sw && audio_pcm_info_eq (&sw->info, as)) {
	return sw;
	}

	if (!pdo->fixed_settings && sw) {
	glue (AUD_close_, TYPE) (card, sw);
	sw = NULL;
	}

	if (sw) {
	HW *hw = sw->hw;

	if (!hw) {
	dolog("Internal logic error: voice `%s' has no backend\n",
	SW_NAME(sw));
	goto fail;
	}

	glue (audio_pcm_sw_fini_, TYPE) (sw);
	if (glue (audio_pcm_sw_init_, TYPE) (sw, hw, name, as)) {
	goto fail;
	}
	} else {
	sw = glue(audio_pcm_create_voice_pair_, TYPE)(s, name, as);
	if (!sw) {
	return NULL;
	}
	}

	sw->card = card;
	sw->vol = nominal_volume;
	sw->callback.fn = callback_fn;
	sw->callback.opaque = callback_opaque;

	#ifdef DEBUG_AUDIO
	dolog ("%s\n", name);
	audio_pcm_print_info ("hw", &sw->hw->info);
	audio_pcm_print_info ("sw", &sw->info);
	#endif

	return sw;

	fail:
	glue (AUD_close_, TYPE) (card, sw);
	return NULL;
	}

	int glue (AUD_is_active_, TYPE) (SW *sw)
	{
	return sw ? sw->active : 0;
	}

	void glue (AUD_init_time_stamp_, TYPE) (SW sw, QEMUAudioTimeStamp ts)
	{
	if (!sw) {
	return;
	}

	ts->old_ts = sw->hw->ts_helper;
	}

	uint64_t glue (AUD_get_elapsed_usec_, TYPE) (SW sw, QEMUAudioTimeStamp ts)
	{
	uint64_t delta, cur_ts, old_ts;

	if (!sw) {
	return 0;
	}

	cur_ts = sw->hw->ts_helper;
	old_ts = ts->old_ts;
	/* dolog ("cur %" PRId64 " old %" PRId64 "\n", cur_ts, old_ts); */

	if (cur_ts >= old_ts) {
	delta = cur_ts - old_ts;
	} else {
	delta = UINT64_MAX - old_ts + cur_ts;
	}

	if (!delta) {
	return 0;
	}

	return muldiv64 (delta, sw->hw->info.freq, 1000000);
	}

	#undef TYPE
	#undef HW
	#undef SW
	#undef HWBUF
	#undef NAME