test: added command line test program for pcm_volume.c

This program is a simple utility for debugging and benchmarking the
software volume code.

test/software_volume.c

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2003-2009 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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
+ */
+
+/*
+ * This program is a command line interface to MPD's software volume
+ * library (pcm_volume.c).
+ *
+ */
+
+#include "pcm_volume.h"
+#include "audio_parser.h"
+#include "audio_format.h"
+
+#include <glib.h>
+
+#include <stddef.h>
+#include <unistd.h>
+
+int main(int argc, char **argv)
+{
+	GError *error = NULL;
+	struct audio_format audio_format = {
+		.sample_rate = 48000,
+		.bits = 16,
+		.channels = 2,
+	};
+	bool ret;
+	static char buffer[4096];
+	ssize_t nbytes;
+
+	if (argc > 2) {
+		g_printerr("Usage: software_voluem [FORMAT] <IN >OUT\n");
+		return 1;
+	}
+
+	if (argc > 1) {
+		ret = audio_format_parse(&audio_format, argv[1], &error);
+		if (!ret) {
+			g_printerr("Failed to parse audio format: %s\n");
+			return 1;
+		}
+	}
+
+	while ((nbytes = read(0, buffer, sizeof(buffer))) > 0) {
+		pcm_volume(buffer, nbytes, &audio_format, PCM_VOLUME_1 / 2);
+		write(1, buffer, nbytes);
+	}
+}