tests: Check for ffmpeg and vorbiscomment before generating music

We can't run most of our tests without the generated tracks.

Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>

tests/Music/Sconscript

@@ -1,7 +1,10 @@
 #!/usr/bin/python
 import subprocess
+import sys
 
 albums  = [ "Hyrule_Symphony.album" ]
 
 for album in albums:
-    subprocess.call(["sh", "gen_tracks.sh", album])
+    ret = subprocess.call(["sh", "gen_tracks.sh", album])
+    if ret != 0:
+        sys.exit(ret)

tests/Music/gen_tracks.sh

@@ -1,5 +1,18 @@
 #!/bin/bash
 
+function check_cmd()
+{
+	echo -n "Checking for $1 ... "
+	CMD=$(which $1 2>/dev/null)
+	if [ $? != 0 ]; then
+		echo "$1 not found"
+		exit 1
+	fi
+	echo $CMD
+}
+check_cmd ffmpeg
+check_cmd vorbiscomment
+
 TRACK=1
 FFMPEG="ffmpeg -hide_banner -nostdin -f s16le -i /dev/zero -codec libvorbis -loglevel warning"