option-parser: Handle short double-arg options

weston allows both short and long style options to take arguments.  In
the case of short options, allow an optional space between the option
name and value.  E.g., previously you could launch weston this way:

  weston -i2 -cmyconfig.ini

now you can also launch it like this:

  weston -i 2 -c myconfig.ini

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>

shared/option-parser.c

@@ -98,14 +98,37 @@ short_option(const struct weston_option *options, int count, char *arg)
 
 				return 1;
 			}
-		} else {
+		} else if (arg[2]) {
 			return handle_option(options + k, arg + 2);
+		} else {
+			return 0;
 		}
 	}
 
 	return 0;
 }
 
+static int
+short_option_with_arg(const struct weston_option *options, int count, char *arg, char *param)
+{
+	int k;
+
+	if (!arg[1])
+		return 0;
+
+	for (k = 0; k < count; k++) {
+		if (options[k].short_name != arg[1])
+			continue;
+
+		if (options[k].type == WESTON_OPTION_BOOLEAN)
+			continue;
+
+		return handle_option(options + k, param);
+	}
+
+	return 0;
+}
+
 int
 parse_options(const struct weston_option *options,
 	      int count, int *argc, char *argv[])
@@ -115,10 +138,22 @@ parse_options(const struct weston_option *options,
 	for (i = 1, j = 1; i < *argc; i++) {
 		if (argv[i][0] == '-') {
 			if (argv[i][1] == '-') {
+				/* Long option, e.g. --foo or --foo=bar */
 				if (long_option(options, count, argv[i]))
 					continue;
-			} else if (short_option(options, count, argv[i]))
-				continue;
+
+			} else {
+				/* Short option, e.g -f or -f42 */
+				if (short_option(options, count, argv[i]))
+					continue;
+
+				/* ...also handle -f 42 */
+				if (i+1 < *argc &&
+				    short_option_with_arg(options, count, argv[i], argv[i+1])) {
+					i++;
+					continue;
+				}
+			}
 		}
 		argv[j++] = argv[i];
 	}