Added ac3dec 0.6.1 with native ALSA driver.

ac3dec/output.c

@@ -0,0 +1,153 @@
+/*
+ *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
+ *
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <sys/asoundlib.h>
+
+typedef signed short sint_16;
+typedef unsigned int uint_32;
+
+#include "output.h"
+
+static int pcm_channels;
+static snd_pcm_t *pcm;
+
+/*
+ * open the audio device for writing to
+ */
+int output_open(int bits, int rate, int channels)
+{
+	char devstr[128];
+	int card, dev;
+	snd_pcm_hw_params_t *params;
+	snd_pcm_sw_params_t *swparams;
+	snd_pcm_sframes_t buffer_time;
+	snd_pcm_sframes_t period_time;
+	int err;
+	snd_pcm_hw_params_alloca(&params);
+	snd_pcm_sw_params_alloca(&swparams);
+
+	pcm_channels = channels;
+
+	/*
+	 * Open the device driver
+	 */
+	card = snd_defaults_pcm_card();
+	dev = snd_defaults_pcm_device();
+	if (card < 0 || dev < 0) {
+		fprintf(stderr, "defaults are not set\n");
+		return -ENODEV;
+	}
+	switch (channels) {
+	case 1:
+	case 2:
+		sprintf(devstr, "plug:%d,%d", card, dev);
+		break;
+	case 4:
+		sprintf(devstr, "surround40:%d,%d", card, dev);
+		break;
+	case 6:
+		sprintf(devstr, "surround51:%d,%d", card, dev);
+		break;
+	default:
+		fprintf(stderr, "%d channels are not supported\n", channels);
+		return -EINVAL;
+	}
+	if ((err = snd_pcm_open(&pcm, devstr, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
+		fprintf(stderr, "snd_pcm_open: %s\n", snd_strerror(err));
+		return err;
+	}
+	err = snd_pcm_hw_params_any(pcm, params);
+	if (err < 0) {
+		fprintf(stderr, "Broken configuration for this PCM: no configurations available");
+		goto __close;
+	}
+	/* set interleaved access */
+	err = snd_pcm_hw_params_set_access(pcm, params,
+					   SND_PCM_ACCESS_RW_INTERLEAVED);
+	if (err < 0) {
+		fprintf(stderr, "Access type not available");
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_format(pcm, params, bits == 16 ? SND_PCM_FORMAT_S16_LE : SND_PCM_FORMAT_U8);
+	if (err < 0) {
+		fprintf(stderr, "Sample format non available");
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_channels(pcm, params, channels);
+	if (err < 0) {
+		fprintf(stderr, "Channels count non available");
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_rate_near(pcm, params, rate, 0);
+	if (err < 0) {
+		fprintf(stderr, "Rate not available");
+		goto __close;
+	}
+	buffer_time = snd_pcm_hw_params_set_buffer_time_near(pcm, params,
+							     500000, 0);
+	if (buffer_time < 0) {
+		fprintf(stderr, "Buffer time not available");
+		goto __close;
+	}
+	period_time = snd_pcm_hw_params_set_period_time_near(pcm, params,
+							     100000, 0);
+	if (period_time < 0) {
+		fprintf(stderr, "Period time not available");
+		goto __close;
+	}
+	if (buffer_time == period_time) {
+		fprintf(stderr, "Buffer time and period time match, could not use\n");
+		goto __close;
+	}
+	if ((err = snd_pcm_hw_params(pcm, params)) < 0) {
+		fprintf(stderr, "PCM hw_params failed: %s\n", snd_strerror(err));
+		goto __close;
+	}
+
+	return 0;
+	
+      __close:
+      	snd_pcm_close(pcm);
+      	pcm = NULL;
+      	return err;
+}
+
+/*
+ * play the sample to the already opened file descriptor
+ */
+void output_play(sint_16* output_samples, uint_32 num_frames)
+{
+	snd_pcm_sframes_t res;
+
+	res = snd_pcm_writei(pcm, (void *)output_samples, num_frames);
+	if (res < 0)
+		fprintf(stderr, "writei returned error: %s\n", snd_strerror(res));
+	else if (res != num_frames)
+		fprintf(stderr, "writei retured %li (expected %li)\n", res, (long)(num_frames));
+}
+
+
+void
+output_close(void)
+{
+	snd_pcm_close(pcm);
+}