1 files changed, 75 insertions, 0 deletions
diff --git a/alsactl/monitor.c b/alsactl/monitor.c
new file mode 100644
index 0000000..12d2450
--- /dev/null
+++ b/alsactl/monitor.c
@@ -0,0 +1,75 @@
+/*
+ *  Advanced Linux Sound Architecture Control Program
+ *  Copyright (c) by Takashi Iwai <tiwai@suse.de>
+ *
+ *   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include "aconfig.h"
+#include "version.h"
+#include <stdio.h>
+#include <alsa/asoundlib.h>
+
+int monitor(const char *name)
+{
+	snd_ctl_t *ctl;
+	snd_ctl_event_t *event;
+	int err;
+
+	if (!name)
+		name = "default";
+
+	err = snd_ctl_open(&ctl, name, SND_CTL_READONLY);
+	if (err < 0) {
+		fprintf(stderr, "Cannot open ctl %s\n", name);
+		return err;
+	}
+	err = snd_ctl_subscribe_events(ctl, 1);
+	if (err < 0) {
+		fprintf(stderr, "Cannot open subscribe events to ctl %s\n", name);
+		snd_ctl_close(ctl);
+		return err;
+	}
+	snd_ctl_event_alloca(&event);
+	while (snd_ctl_read(ctl, event) > 0) {
+		unsigned int mask;
+
+		if (snd_ctl_event_get_type(event) != SND_CTL_EVENT_ELEM)
+			continue;
+
+		printf("#%d (%i,%i,%i,%s,%i)",
+		       snd_ctl_event_elem_get_numid(event),
+		       snd_ctl_event_elem_get_interface(event),
+		       snd_ctl_event_elem_get_device(event),
+		       snd_ctl_event_elem_get_subdevice(event),
+		       snd_ctl_event_elem_get_name(event),
+		       snd_ctl_event_elem_get_index(event));
+
+		mask = snd_ctl_event_elem_get_mask(event);
+		if (mask & SND_CTL_EVENT_MASK_VALUE)
+			printf(" VALUE");
+		if (mask & SND_CTL_EVENT_MASK_INFO)
+			printf(" INFO");
+		if (mask & SND_CTL_EVENT_MASK_ADD)
+			printf(" ADD");
+		if (mask & SND_CTL_EVENT_MASK_TLV)
+			printf(" TLV");
+		if (mask == SND_CTL_EVENT_MASK_REMOVE)
+			printf(" REMOVE");
+		printf("\n");
+	}
+	snd_ctl_close(ctl);
+	return 0;
+}