alsa: use audio_pcm_hw_clip_out (541ba4e7) · Commits · SUMMER2020 / students / proj-2021291

audio/alsaaudio.c

+43 −45

Original line number	Diff line number	Diff line
		@@ -42,6 +42,8 @@ struct pollhlp {

		typedef struct ALSAVoiceOut {
		HWVoiceOut hw;
		int wpos;
		int pending;
		void *pcm_buf;
		snd_pcm_t *handle;
		struct pollhlp pollhlp;
		@@ -592,7 +594,7 @@ static int alsa_open (int in, struct alsa_params_req *req,
		goto err;
		}

		if ((req->override_mask & 1) && (obt - req->period_size))
		if (((req->override_mask & 1) && (obt - req->period_size)))
		dolog ("Requested period %s %u was rejected, using %lu\n",
		size_in_usec ? "time" : "size", req->period_size, obt);
		}
		@@ -698,41 +700,19 @@ static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
		return avail;
		}

		static int alsa_run_out (HWVoiceOut *hw)
		static void alsa_write_pending (ALSAVoiceOut *alsa)
		{
		ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
		int rpos, live, decr;
		int samples;
		uint8_t *dst;
		struct st_sample *src;
		snd_pcm_sframes_t avail;

		live = audio_pcm_hw_get_live_out (hw);
		if (!live) {
		return 0;
		}
		HWVoiceOut *hw = &alsa->hw;

		avail = alsa_get_avail (alsa->handle);
		if (avail < 0) {
		dolog ("Could not get number of available playback frames\n");
		return 0;
		}
		while (alsa->pending) {
		int left_till_end_samples = hw->samples - alsa->wpos;
		int len = audio_MIN (alsa->pending, left_till_end_samples);
		char *src = advance (alsa->pcm_buf, alsa->wpos << hw->info.shift);

		decr = audio_MIN (live, avail);
		samples = decr;
		rpos = hw->rpos;
		while (samples) {
		int left_till_end_samples = hw->samples - rpos;
		int len = audio_MIN (samples, left_till_end_samples);
		while (len) {
		snd_pcm_sframes_t written;

		src = hw->mix_buf + rpos;
		dst = advance (alsa->pcm_buf, rpos << hw->info.shift);

		hw->clip (dst, src, len);

		while (len) {
		written = snd_pcm_writei (alsa->handle, dst, len);
		written = snd_pcm_writei (alsa->handle, src, len);

		if (written <= 0) {
		switch (written) {
		@@ -740,13 +720,13 @@ static int alsa_run_out (HWVoiceOut *hw)
		if (conf.verbose) {
		dolog ("Failed to write %d frames (wrote zero)\n", len);
		}
		goto exit;
		return;

		case -EPIPE:
		if (alsa_recover (alsa->handle)) {
		alsa_logerr (written, "Failed to write %d frames\n",
		len);
		goto exit;
		return;
		}
		if (conf.verbose) {
		dolog ("Recovering from playback xrun\n");
		@@ -759,7 +739,7 @@ static int alsa_run_out (HWVoiceOut *hw)
		if (alsa_resume (alsa->handle)) {
		alsa_logerr (written, "Failed to write %d frames\n",
		len);
		goto exit;
		return;
		}
		if (conf.verbose) {
		dolog ("Resuming suspended output stream\n");
		@@ -767,25 +747,43 @@ static int alsa_run_out (HWVoiceOut *hw)
		continue;

		case -EAGAIN:
		goto exit;
		return;

		default:
		alsa_logerr (written, "Failed to write %d frames to %p\n",
		len, dst);
		goto exit;
		alsa_logerr (written, "Failed to write %d frames from %p\n",
		len, src);
		return;
		}
		}

		rpos = (rpos + written) % hw->samples;
		samples -= written;
		alsa->wpos = (alsa->wpos + written) % hw->samples;
		alsa->pending -= written;
		len -= written;
		dst = advance (dst, written << hw->info.shift);
		src += written;
		}
		}
		}

		exit:
		hw->rpos = rpos;
		static int alsa_run_out (HWVoiceOut *hw)
		{
		ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
		int live, decr;
		snd_pcm_sframes_t avail;

		live = audio_pcm_hw_get_live_out (hw);
		if (!live) {
		return 0;
		}

		avail = alsa_get_avail (alsa->handle);
		if (avail < 0) {
		dolog ("Could not get number of available playback frames\n");
		return 0;
		}

		decr = audio_MIN (live, avail);
		decr = audio_pcm_hw_clip_out (hw, alsa->pcm_buf, decr, alsa->pending);
		alsa->pending += decr;
		alsa_write_pending (alsa);
		return decr;
		}