import

1 files changed, 160 insertions, 0 deletions

diff --git a/galsa.c b/galsa.c
new file mode 100644
index 0000000..8e02c61
--- /dev/null
+++ b/galsa.c
@@ -0,0 +1,160 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <ctype.h>
+
+#include "galsa.h"
+
+struct device *device_open(const char *path, unsigned rate, int chan, size_t pktsize)
+{
+	struct device *dev;
+	snd_pcm_hw_params_t *hw_params = NULL;
+	snd_pcm_t *hdl = NULL;
+	char errmsg[256];
+
+#define E(x) do { int err; if ((err = x) < 0) { \
+	snprintf(errmsg, sizeof(errmsg), "%s:%d/%s(): %s() failed: %s (%d)\n",\
+		__FILE__, __LINE__, __func__, #x, snd_strerror(err), err); \
+	goto out_err; \
+	} } while (0)
+
+	printf("Opening alsa://%s with %d ch %dHz...\n", path, chan, rate);
+	E(snd_pcm_open(&hdl, path, SND_PCM_STREAM_CAPTURE, 0));
+	E(snd_pcm_hw_params_malloc(&hw_params));
+	E(snd_pcm_hw_params_any(hdl, hw_params));
+	E(snd_pcm_hw_params_set_access(hdl, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED));
+	E(snd_pcm_hw_params_set_format(hdl, hw_params, SND_PCM_FORMAT_S16_LE));
+	E(snd_pcm_hw_params_set_rate_near(hdl, hw_params, &rate, 0));
+	E(snd_pcm_hw_params_set_channels(hdl, hw_params, chan));
+	E(snd_pcm_hw_params(hdl, hw_params));
+	snd_pcm_hw_params_free(hw_params);
+	hw_params = NULL;
+
+	E(snd_pcm_prepare(hdl));
+	printf("... Ok.\n");
+
+	dev = (struct device *)malloc(sizeof(struct device));
+	dev->path = strdup(path);
+	dev->rate = rate;
+	dev->chan = chan;
+	dev->handle = hdl;
+	dev->thread = NULL;
+	dev->queue = g_async_queue_new();
+	dev->state = DEV_OPEN;
+	dev->pktsize = pktsize;
+	return dev;
+
+out_err:
+	if (hw_params)
+		snd_pcm_hw_params_free(hw_params);
+	if (hdl)
+		snd_pcm_close(hdl);
+	return NULL;
+}
+
+static gpointer threadf(gpointer param)
+{
+	struct device *dev = (struct device *)param;
+	struct qe *ent, *entx;
+	int pcmreturn;
+	ptrdiff_t pos;
+
+	do {
+		ent = malloc(sizeof(struct qe) +
+			dev->pktsize * sizeof(sample) * dev->chan);
+		ent->message = QE_DATA;
+		ent->size = dev->pktsize;
+		pos = 0;
+
+		do {
+			while ((pcmreturn = snd_pcm_readi(dev->handle,
+				ent->samples + pos, ent->size - pos)) < 0) {
+
+				entx = calloc(sizeof(struct qe), 1);
+				entx->message = QE_ERROR;
+				entx->errcode = pcmreturn;
+				asprintf(&entx->errp,
+					"PCM read failed: %s (%d)",
+					snd_strerror(pcmreturn), pcmreturn);
+				g_async_queue_push(dev->queue, entx);
+
+				if (dev->state != DEV_RUNNING) {
+					free(ent);
+					goto out;
+				}
+
+				snd_pcm_prepare(dev->handle);
+			}
+			pos += pcmreturn;
+		} while (pos < ent->size);
+		g_async_queue_push(dev->queue, ent);
+	} while (dev->state == DEV_RUNNING);
+
+out:
+	entx = calloc(sizeof(struct qe), 1);
+	entx->message = QE_STOPPED;
+	g_async_queue_push(dev->queue, entx);
+
+	return NULL;
+}
+
+void device_start(struct device *dev)
+{
+	GError *error = NULL;
+	if (dev->thread)
+		return;
+	dev->state = DEV_RUNNING;
+	dev->thread = g_thread_create(threadf, dev, 0, &error);
+}
+
+void device_stop(struct device *dev)
+{
+	if (dev->state == DEV_RUNNING)
+		dev->state = DEV_STOPREQ;
+}
+
+void device_stop_wait(struct device *dev)
+{
+	int got_stop = 0, iter = 0;
+	struct qe *qe;
+
+	if (dev->state == DEV_OPEN)
+		return;
+
+	device_stop(dev);
+
+	while (!got_stop && iter++ < 10) {
+		qe = (struct qe *)g_async_queue_timeout_pop(dev->queue, 250000);
+		switch (qe->message) {
+		case QE_DATA:
+			break;
+		case QE_ERROR:
+			free(qe->errp);
+			break;
+		case QE_STOPPED:
+			got_stop = 1;
+			break;
+		}
+		free(qe);
+	}
+	if (!got_stop)
+		fprintf(stderr, "failed to terminate recording thread!\n");
+	dev->state = DEV_OPEN;
+}
+
+void device_stop_done(struct device *dev)
+{
+	dev->state = DEV_OPEN;
+}
+
+void device_close(struct device *dev)
+{
+	device_stop_wait(dev);
+
+	snd_pcm_close(dev->handle);
+	free(dev->path);
+	free(dev);
+}
+
+