scripts: Update git-version-gen to be more useful.

git-version-gen

@@ -11,10 +11,16 @@ then
 	VN=$(cat version)
 elif test -d .git
 then
-	VN=$(git describe 2>/dev/null) &&
-	git update-index -q --refresh
-#	test -z "$(git diff-index --name-only HEAD --)" ||
-#	VN="$VN-dirty"
+	VN=$(git describe 2>/dev/null) && git update-index -q --refresh
+	HEAD=$(git rev-parse --verify --short HEAD 2>/dev/null)
+
+	if [ -n "$VN" ] ; then
+	    VN="$VN-$HEAD"
+	else
+	    VN="none-$HEAD"
+	fi
+
+	test -z "$(git diff-index --name-only HEAD --)" || VN="$VN-dirty"
 else
 	VN="$DEF_VER"
 fi
@@ -30,9 +36,13 @@ then
 else
 	VC=unset
 fi
-test "\"$VN\"" = "$VC" -a "\"-$APP\"" = "$VM" || {
+if [ -n "$APP" ] ; then
+    APP="-$APP"
+fi
+
+test "\"$VN\"" = "$VC" -a "\"$APP\"" = "$VM" || {
 	echo "#define SYSTEM_VERSION \"$VN\"" >$GVF
-	echo "#define SYSTEM_APP \"-$APP\"" >>$GVF
+	echo "#define SYSTEM_APP \"$APP\"" >>$GVF
 
 }