From: Andre Noll <maan@systemlinux.org>
Date: Sun, 15 Jul 2012 17:58:59 +0000 (+0200)
Subject: fade: Introduce --mixer-api to choose between ALSA and OSS.
X-Git-Tag: v0.4.12~10^2~4
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=0968b226713f7bab3be9185b426f766932394bc7;p=paraslash.git

fade: Introduce --mixer-api to choose between ALSA and OSS.

Currently, if both OSS and ALSA are supported, there is no way to
select the OSS mixer API.

This adds a new option to para_fade which allows to force the
given mixer API.
---

diff --git a/fade.c b/fade.c
index 1bfa0ba1..cbfb6230 100644
--- a/fade.c
+++ b/fade.c
@@ -23,6 +23,7 @@ enum mixer_id {MIXER_ENUM};
 static char *mixer_name[] = {MIXER_NAMES};
 DECLARE_MIXER_INITS;
 static struct mixer supported_mixer[] = {MIXER_ARRAY};
+#define FOR_EACH_MIXER(i) for ((i) = 0; (i) < NUM_SUPPORTED_MIXERS; (i)++)
 
 __printf_2_3 void date_log(__a_unused int ll, const char *fmt, ...)
 {
@@ -233,7 +234,7 @@ static void init_mixers(void)
 {
 	int i;
 
-	for (i = 0; i < NUM_SUPPORTED_MIXERS; i++) {
+	FOR_EACH_MIXER(i) {
 		struct mixer *m = &supported_mixer[i];
 		PARA_DEBUG_LOG("initializing mixer API #%d (%s)\n",
 			i, mixer_name[i]);
@@ -259,6 +260,29 @@ static int set_channel(struct mixer *m, struct mixer_handle *h)
 	return ret;
 }
 
+static struct mixer *get_mixer_or_die(void)
+{
+	int i;
+
+	if (!conf.mixer_api_given)
+		i = DEFAULT_MIXER;
+	else
+		FOR_EACH_MIXER(i)
+			if (!strcmp(mixer_name[i], conf.mixer_api_arg))
+				break;
+	if (i < NUM_SUPPORTED_MIXERS) {
+		PARA_NOTICE_LOG("using %s mixer API\n", mixer_name[i]);
+		return supported_mixer + i;
+	}
+	printf("available mixer APIs: ");
+	FOR_EACH_MIXER(i) {
+		int d = (i == DEFAULT_MIXER);
+		printf("%s%s%s ", d? "[" : "", mixer_name[i], d? "]" : "");
+	}
+	printf("\n");
+	exit(EXIT_FAILURE);
+}
+
 int main(int argc, char *argv[])
 {
 	int ret;
@@ -286,8 +310,7 @@ int main(int argc, char *argv[])
 			&conf, &params);
 	}
 	init_mixers();
-	m = &supported_mixer[DEFAULT_MIXER];
-	PARA_INFO_LOG("using %s mixer\n", mixer_name[DEFAULT_MIXER]);
+	m = get_mixer_or_die();
 	ret = m->open(conf.mixer_device_arg, &h);
 	if (ret < 0)
 		goto out;
diff --git a/m4/gengetopt/fade.m4 b/m4/gengetopt/fade.m4
index 42f135fa..450e0542 100644
--- a/m4/gengetopt/fade.m4
+++ b/m4/gengetopt/fade.m4
@@ -32,6 +32,18 @@ option "config-file" c
 	string typestr = "filename"
 	optional
 
+option "mixer-api" a
+#~~~~~~~~~~~~~~~~~~~
+"choose the mixer API"
+	string typestr = "api"
+	optional
+	details = "
+		ALSA is preferred over OSS if both APIs are supported
+		and this option is not given. To see the supported
+		mixer APIs, use this option with an invalid string
+		as the mixer API, e.g. --mixer-api help.
+	"
+
 option "mixer-device" m
 #~~~~~~~~~~~~~~~~~~~~~~
 "choose mixer device"