q6voiced: port to libasound

Tinyalsa is an Android library, very rarely packaged by traditional
Linux distributions. It can easily be replaced with the more usual
`libasound` in this case, which will make packaging it easier.

meson.build

@@ -2,9 +2,9 @@ project('q6voiced', 'c')
 
 pkg = import('pkgconfig')
 dbus = dependency('dbus-1')
-tinyalsa = dependency('tinyalsa')
+alsa = dependency('alsa')
 
 executable('q6voiced',
            'q6voiced.c',
-           dependencies: [dbus, tinyalsa],
+           dependencies: [dbus, alsa],
            install: true)

q6voiced.c

@@ -2,20 +2,12 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <dbus/dbus.h>
-#include <tinyalsa/asoundlib.h>
-
-/* Note: These parameters have little relevance (no audio data written) */
-struct pcm_config pcm_config_voice_call = {
-	.channels	= 1,
-	.rate		= 8000,
-	.period_size	= 160,
-	.period_count	= 2,
-	.format		= PCM_FORMAT_S16_LE,
-};
+#include <string.h>
+#include <alsa/asoundlib.h>
 
 struct q6voiced {
-	unsigned int card, device;
-	struct pcm *tx, *rx;
+	char card[64];
+	snd_pcm_t *tx, *rx;
 };
 
 static void q6voiced_open(struct q6voiced *v)
@@ -27,14 +19,31 @@ static void q6voiced_open(struct q6voiced *v)
 	 * Opening the PCM devices starts the stream.
 	 * This should be replaced by a codec2codec link probably.
 	 */
-	v->tx = pcm_open(v->card, v->device, PCM_IN, &pcm_config_voice_call);
-	v->rx = pcm_open(v->card, v->device, PCM_OUT, &pcm_config_voice_call);
-	if (!pcm_is_ready(v->tx) || pcm_prepare(v->tx))
+	if (snd_pcm_open(&v->tx, v->card, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK) < 0 ||
+	    snd_pcm_set_params(v->tx, SND_PCM_FORMAT_S16_LE, SND_PCM_ACCESS_RW_INTERLEAVED, 1, 8000, 0, 500000) < 0 ||
+	    snd_pcm_prepare(v->tx) < 0) {
 		perror("Failed to open tx");
-	if (!pcm_is_ready(v->rx) || pcm_prepare(v->rx))
+		goto error;
+	}
+	if (snd_pcm_open(&v->rx, v->card, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK) < 0 ||
+	    snd_pcm_set_params(v->rx, SND_PCM_FORMAT_S16_LE, SND_PCM_ACCESS_RW_INTERLEAVED, 1, 8000, 0, 500000) < 0 ||
+	    snd_pcm_prepare(v->rx) < 0) {
 		perror("Failed to open rx");
+		goto error;
+	}
 
 	printf("PCM devices were opened.\n");
+	return;
+
+error:
+	if (v->tx) {
+		snd_pcm_close(v->tx);
+		v->tx = NULL;
+	}
+	if (v->rx) {
+		snd_pcm_close(v->rx);
+		v->rx = NULL;
+	}
 }
 
 static void q6voiced_close(struct q6voiced *v)
@@ -42,8 +51,8 @@ static void q6voiced_close(struct q6voiced *v)
 	if (!v->tx)
 		return; /* Not active */
 
-	pcm_close(v->rx);
-	pcm_close(v->tx);
+	snd_pcm_close(v->tx);
+	snd_pcm_close(v->rx);
 	v->rx = v->tx = NULL;
 
 	printf("PCM devices were closed.\n");
@@ -112,11 +121,13 @@ int main(int argc, char **argv)
 	DBusConnection *conn;
 	DBusError err;
 
-	if (argc != 2 || sscanf(argv[1], "hw:%u,%u", &v.card, &v.device) != 2) {
+	if (argc != 2) {
 		fprintf(stderr, "Usage: q6voiced hw:<card>,<device>\n");
 		return 1;
 	}
 
+	strlcpy(v.card, argv[1], sizeof(v.card) - 1);
+
 	// See: http://web.archive.org/web/20100309103206/http://dbus.freedesktop.org/doc/dbus/libdbus-tutorial.html
 	// "Receiving a Signal"