stripspace: use parse-options for command-line parsing

Use parse-options to parse command-line options instead of a
hand-crafted implementation.  The users can now use a unique
prefix of the long option to say e.g. "git stripspace --strip".

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/stripspace.c

@@ -1,5 +1,6 @@
 #include "builtin.h"
 #include "cache.h"
+#include "parse-options.h"
 #include "strbuf.h"
 
 static void comment_lines(struct strbuf *buf)
@@ -12,41 +13,45 @@ static void comment_lines(struct strbuf *buf)
 	free(msg);
 }
 
-static const char *usage_msg = "\n"
-"  git stripspace [-s | --strip-comments] < input\n"
-"  git stripspace [-c | --comment-lines] < input";
+static const char * const stripspace_usage[] = {
+	N_("git stripspace [-s | --strip-comments] < input"),
+	N_("git stripspace [-c | --comment-lines] < input"),
+	NULL
+};
+
+enum stripspace_mode {
+	STRIP_DEFAULT = 0,
+	STRIP_COMMENTS,
+	COMMENT_LINES
+};
 
 int cmd_stripspace(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf buf = STRBUF_INIT;
-	int strip_comments = 0;
-	enum { INVAL = 0, STRIP_SPACE = 1, COMMENT_LINES = 2 } mode = STRIP_SPACE;
-
-	if (argc == 2) {
-		if (!strcmp(argv[1], "-s") ||
-		    !strcmp(argv[1], "--strip-comments")) {
-			strip_comments = 1;
-		} else if (!strcmp(argv[1], "-c") ||
-			   !strcmp(argv[1], "--comment-lines")) {
-			mode = COMMENT_LINES;
-		} else {
-			mode = INVAL;
-		}
-	} else if (argc > 1) {
-		mode = INVAL;
-	}
-
-	if (mode == INVAL)
-		usage(usage_msg);
-
-	if (strip_comments || mode == COMMENT_LINES)
+	enum stripspace_mode mode = STRIP_DEFAULT;
+
+	const struct option options[] = {
+		OPT_CMDMODE('s', "strip-comments", &mode,
+			    N_("skip and remove all lines starting with comment character"),
+			    STRIP_COMMENTS),
+		OPT_CMDMODE('c', "comment-lines", &mode,
+			    N_("prepend comment character and blank to each line"),
+			    COMMENT_LINES),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, prefix, options, stripspace_usage, 0);
+	if (argc)
+		usage_with_options(stripspace_usage, options);
+
+	if (mode == STRIP_COMMENTS || mode == COMMENT_LINES)
 		git_config(git_default_config, NULL);
 
 	if (strbuf_read(&buf, 0, 1024) < 0)
 		die_errno("could not read the input");
 
-	if (mode == STRIP_SPACE)
-		strbuf_stripspace(&buf, strip_comments);
+	if (mode == STRIP_DEFAULT || mode == STRIP_COMMENTS)
+		strbuf_stripspace(&buf, mode == STRIP_COMMENTS);
 	else
 		comment_lines(&buf);