mixer_control: close mixer on failure

src/mixer/alsa_mixer.c

@@ -162,7 +162,6 @@ alsa_mixer_get_volume(struct mixer *mixer)
 	if (err < 0) {
 		g_warning("problems getting alsa volume: %s (snd_mixer_%s)\n",
 			  snd_strerror(err), "handle_events");
-		alsa_mixer_close(mixer);
 		return false;
 	}
 
@@ -172,7 +171,6 @@ alsa_mixer_get_volume(struct mixer *mixer)
 	if (err < 0) {
 		g_warning("problems getting alsa volume: %s (snd_mixer_%s)\n",
 			  snd_strerror(err), "selem_get_playback_volume");
-		alsa_mixer_close(mixer);
 		return false;
 	}
 
@@ -216,7 +214,6 @@ alsa_mixer_set_volume(struct mixer *mixer, unsigned volume)
 	if (err < 0) {
 		g_warning("problems setting alsa volume: %s\n",
 			  snd_strerror(err));
-		alsa_mixer_close(mixer);
 		return false;
 	}
 

src/mixer/oss_mixer.c

@@ -150,7 +150,6 @@ oss_mixer_get_volume(struct mixer *mixer)
 
 	ret = ioctl(om->device_fd, MIXER_READ(om->volume_control), &level);
 	if (ret < 0) {
-		oss_mixer_close(mixer);
 		g_warning("unable to read oss volume\n");
 		return false;
 	}
@@ -184,7 +183,6 @@ oss_mixer_set_volume(struct mixer *mixer, unsigned volume)
 	ret = ioctl(om->device_fd, MIXER_WRITE(om->volume_control), &level);
 	if (ret < 0) {
 		g_warning("unable to set oss volume\n");
-		oss_mixer_close(mixer);
 		return false;
 	}
 

src/mixer_control.c

@@ -110,6 +110,18 @@ mixer_auto_close(struct mixer *mixer)
 		mixer_close(mixer);
 }
 
+/*
+ * Close the mixer due to failure.  The mutex must be locked before
+ * calling this function.
+ */
+static void
+mixer_failed(struct mixer *mixer)
+{
+	assert(mixer->open);
+
+	mixer_close(mixer);
+}
+
 int
 mixer_get_volume(struct mixer *mixer)
 {
@@ -124,6 +136,8 @@ mixer_get_volume(struct mixer *mixer)
 
 	if (mixer->open) {
 		volume = mixer->plugin->get_volume(mixer);
+		if (volume < 0)
+			mixer_failed(mixer);
 	} else
 		volume = -1;
 
@@ -146,6 +160,8 @@ mixer_set_volume(struct mixer *mixer, unsigned volume)
 
 	if (mixer->open) {
 		success = mixer->plugin->set_volume(mixer, volume);
+		if (!success)
+			mixer_failed(mixer);
 	} else
 		success = false;