amixer - Fix selection of enum items

The item names with channel specifier cannot be chosen correctly
via amixer sset.  For example, 'Front Mic' is handled as 'Mic' since
the channel specificier 'Front' is omitted.

The idea of channel specifier is basically non-sense for enum items,
and this also makes the code very messy.

The patch fixes the behavior of enum items and gives the code clean-up
for sset command.

amixer/amixer.c

@@ -1369,67 +1369,35 @@ static int get_enum_item_index(snd_mixer_elem_t *elem, char **ptrp)
 	return -1;
 }
 
-static int sset(unsigned int argc, char *argv[], int roflag, int keep_handle)
+static int sset_enum(snd_mixer_elem_t *elem, unsigned int argc, char **argv)
+{
+	unsigned int idx, chn = 0;
+	int check_flag = -1;
+
+	for (idx = 1; idx < argc; idx++) {
+		char *ptr = argv[idx];
+		while (*ptr) {
+			int ival = get_enum_item_index(elem, &ptr);
+			if (ival < 0)
+				return check_flag;
+			if (snd_mixer_selem_set_enum_item(elem, chn, ival) >= 0)
+				check_flag = 1;
+			/* skip separators */
+			while (*ptr == ',' || isspace(*ptr))
+				ptr++;
+		}
+	}
+	return check_flag;
+}
+
+static int sset_channels(snd_mixer_elem_t *elem, unsigned int argc, char **argv)
 {
-	int err, check_flag;
-	unsigned int idx;
-	snd_mixer_selem_channel_id_t chn;
 	unsigned int channels = ~0U;
 	unsigned int dir = 3, okflag = 3;
-	static snd_mixer_t *handle = NULL;
+	unsigned int idx;
-	snd_mixer_elem_t *elem;
+	snd_mixer_selem_channel_id_t chn;
-	snd_mixer_selem_id_t *sid;
+	int check_flag = -1;
-	snd_mixer_selem_id_alloca(&sid);
 
-	if (argc < 1) {
-		fprintf(stderr, "Specify a scontrol identifier: 'name',index\n");
-		return 1;
-	}
-	if (parse_simple_id(argv[0], sid)) {
-		fprintf(stderr, "Wrong scontrol identifier: %s\n", argv[0]);
-		return 1;
-	}
-	if (!roflag && argc < 2) {
-		fprintf(stderr, "Specify what you want to set...\n");
-		return 1;
-	}
-	if (handle == NULL) {
-		if ((err = snd_mixer_open(&handle, 0)) < 0) {
-			error("Mixer %s open error: %s\n", card, snd_strerror(err));
-			return err;
-		}
-		if (smixer_level == 0 && (err = snd_mixer_attach(handle, card)) < 0) {
-			error("Mixer attach %s error: %s", card, snd_strerror(err));
-			snd_mixer_close(handle);
-			handle = NULL;
-			return err;
-		}
-		if ((err = snd_mixer_selem_register(handle, smixer_level > 0 ? &smixer_options : NULL, NULL)) < 0) {
-			error("Mixer register error: %s", snd_strerror(err));
-			snd_mixer_close(handle);
-			handle = NULL;
-			return err;
-		}
-		err = snd_mixer_load(handle);
-		if (err < 0) {
-			error("Mixer %s load error: %s", card, snd_strerror(err));
-			snd_mixer_close(handle);
-			handle = NULL;
-			return err;
-		}
-	}
-	elem = snd_mixer_find_selem(handle, sid);
-	if (!elem) {
-		if (ignore_error)
-			return 0;
-		error("Unable to find simple control '%s',%i\n", snd_mixer_selem_id_get_name(sid), snd_mixer_selem_id_get_index(sid));
-		snd_mixer_close(handle);
-		handle = NULL;
-		return -ENOENT;
-	}
-	if (roflag)
-		goto __skip_write;
-	check_flag = 0;
 	for (idx = 1; idx < argc; idx++) {
 		char *ptr = argv[idx], *optr;
 		int multi, firstchn = 1;
@@ -1447,19 +1415,6 @@ static int sset(unsigned int argc, char *argv[], int roflag, int keep_handle)
 
 			if (!(channels & (1 << chn)))
 				continue;
-			/* enum control */
-			if (snd_mixer_selem_is_enumerated(elem)) {
-				int idx = get_enum_item_index(elem, &ptr);
-				if (idx < 0) {
-					break;
-				} else {
-					if (snd_mixer_selem_set_enum_item(elem, chn, idx) >= 0)
-						check_flag = 1;
-				}
-				if (!multi)
-					ptr = optr;
-				continue;
-			}
 
 			if ((dir & 1) && snd_mixer_selem_has_playback_channel(elem, chn)) {
 				sptr = ptr;
@@ -1540,35 +1495,94 @@ static int sset(unsigned int argc, char *argv[], int roflag, int keep_handle)
 					if (dir & 2)
 						error("Unknown capture setup '%s'..", ptr);
 				}
-				if (! keep_handle) {
+				return 0; /* just skip it */
-					snd_mixer_close(handle);
-					handle = NULL;
-				}
-				return 0;
 			}
 			if (!multi)
 				ptr = optr;
 			firstchn = 0;
 		}
 	}
-	if (!check_flag) {
+	return check_flag;
-		error("Invalid command!");
-		if (! keep_handle) {
-			snd_mixer_close(handle);
-			handle = NULL;
 }
+
+static int sset(unsigned int argc, char *argv[], int roflag, int keep_handle)
+{
+	int err = 0;
+	static snd_mixer_t *handle = NULL;
+	snd_mixer_elem_t *elem;
+	snd_mixer_selem_id_t *sid;
+	snd_mixer_selem_id_alloca(&sid);
+
+	if (argc < 1) {
+		fprintf(stderr, "Specify a scontrol identifier: 'name',index\n");
 		return 1;
 	}
-      __skip_write:
+	if (parse_simple_id(argv[0], sid)) {
+		fprintf(stderr, "Wrong scontrol identifier: %s\n", argv[0]);
+		return 1;
+	}
+	if (!roflag && argc < 2) {
+		fprintf(stderr, "Specify what you want to set...\n");
+		return 1;
+	}
+	if (handle == NULL) {
+		if ((err = snd_mixer_open(&handle, 0)) < 0) {
+			error("Mixer %s open error: %s\n", card, snd_strerror(err));
+			return err;
+		}
+		if (smixer_level == 0 && (err = snd_mixer_attach(handle, card)) < 0) {
+			error("Mixer attach %s error: %s", card, snd_strerror(err));
+			snd_mixer_close(handle);
+			handle = NULL;
+			return err;
+		}
+		if ((err = snd_mixer_selem_register(handle, smixer_level > 0 ? &smixer_options : NULL, NULL)) < 0) {
+			error("Mixer register error: %s", snd_strerror(err));
+			snd_mixer_close(handle);
+			handle = NULL;
+			return err;
+		}
+		err = snd_mixer_load(handle);
+		if (err < 0) {
+			error("Mixer %s load error: %s", card, snd_strerror(err));
+			snd_mixer_close(handle);
+			handle = NULL;
+			return err;
+		}
+	}
+	elem = snd_mixer_find_selem(handle, sid);
+	if (!elem) {
+		if (ignore_error)
+			return 0;
+		error("Unable to find simple control '%s',%i\n", snd_mixer_selem_id_get_name(sid), snd_mixer_selem_id_get_index(sid));
+		snd_mixer_close(handle);
+		handle = NULL;
+		return -ENOENT;
+	}
+	if (!roflag) {
+		/* enum control */
+		if (snd_mixer_selem_is_enumerated(elem))
+			err = sset_enum(elem, argc, argv);
+		else
+			err = sset_channels(elem, argc, argv);
+
+		if (!err)
+			goto done;
+		if (err < 0) {
+			error("Invalid command!");
+			goto done;
+		}
+	}
 	if (!quiet) {
 		printf("Simple mixer control '%s',%i\n", snd_mixer_selem_id_get_name(sid), snd_mixer_selem_id_get_index(sid));
 		show_selem(handle, sid, "  ", 1);
 	}
+ done:
 	if (! keep_handle) {
 		snd_mixer_close(handle);
 		handle = NULL;
 	}
-	return 0;
+	return err < 0 ? 1 : 0;
 }
 
 static void events_info(snd_hctl_elem_t *helem)