util: new function unquote()

Refactor to reduce code duplication

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/cgroup.c

@@ -89,18 +89,9 @@ static void cgset(const char *path, char *ctrl, char *prop)
 	*val++ = 0;
 
 	/* unquote value, if quoted */
-	if (val[0] == '"' || val[0] == '\'') {
-		char q = val[0];
-		char *end;
-
-		end = strchr(&val[1], q);
-		if (!end) {
-			errx(1, "Syntax error, unterminated quote in %s/%s.%s=%s", path, ctrl, prop, val);
-			return;
-		}
-
-		val++;
-		*end = 0;
+	if (unquote(&val, NULL)) {
+		errx(1, "Syntax error, unterminated quote in %s/%s.%s=%s", path, ctrl, prop, val);
+		return;
 	}
 
 	/* disallow sneaky relative paths */