builtin/diagnose.c: add '--mode' option

Create '--mode=<mode>' option in 'git diagnose' to allow users to optionally
select non-default diagnostic information to include in the output archive.
Additionally, document the currently-available modes, emphasizing the
importance of not sharing a '--mode=all' archive publicly due to the
presence of sensitive information.

Note that the option parsing callback - 'option_parse_diagnose()' - is added
to 'diagnose.c' rather than 'builtin/diagnose.c' so that it may be reused in
future callers configuring a diagnostics archive.

Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/diagnose.c b/diagnose.c
index 9270056db2..beb0a8741b 100644
--- a/diagnose.c
+++ b/diagnose.c
@@ -13,6 +13,36 @@ struct archive_dir {
 	int recursive;
 };
 
+struct diagnose_option {
+	enum diagnose_mode mode;
+	const char *option_name;
+};
+
+static struct diagnose_option diagnose_options[] = {
+	{ DIAGNOSE_STATS, "stats" },
+	{ DIAGNOSE_ALL, "all" },
+};
+
+int option_parse_diagnose(const struct option *opt, const char *arg, int unset)
+{
+	int i;
+	enum diagnose_mode *diagnose = opt->value;
+
+	if (!arg) {
+		*diagnose = unset ? DIAGNOSE_NONE : DIAGNOSE_STATS;
+		return 0;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(diagnose_options); i++) {
+		if (!strcmp(arg, diagnose_options[i].option_name)) {
+			*diagnose = diagnose_options[i].mode;
+			return 0;
+		}
+	}
+
+	return error(_("invalid --%s value '%s'"), opt->long_name, arg);
+}
+
 static void dir_file_stats_objects(const char *full_path, size_t full_path_len,
 				   const char *file_name, void *data)
 {