ui-shared: add cgit_date_mode()

This returns the correct mode value for use with Git's show_date() based
on the current CGit configuration and will be used in the following
patches.

Signed-off-by: John Keeping <john@keeping.me.uk>

ui-shared.c

@@ -627,6 +627,15 @@ void cgit_print_date(time_t secs, const char *format, int local_time)
 	html_txt(fmt_date(secs, format, local_time));
 }
 
+const struct date_mode *cgit_date_mode(const char *format)
+{
+	static struct date_mode mode;
+	mode.type = DATE_STRFTIME;
+	mode.strftime_fmt = format;
+	mode.local = ctx.cfg.local_time;
+	return &mode;
+}
+
 static void print_rel_date(time_t t, double value,
 	const char *class, const char *suffix)
 {

ui-shared.h

@@ -61,6 +61,7 @@ __attribute__((format (printf,1,2)))
 extern void cgit_print_error(const char *fmt, ...);
 __attribute__((format (printf,1,0)))
 extern void cgit_vprint_error(const char *fmt, va_list ap);
+extern const struct date_mode *cgit_date_mode(const char *format);
 extern void cgit_print_date(time_t secs, const char *format, int local_time);
 extern void cgit_print_age(time_t t, time_t max_relative);
 extern void cgit_print_http_headers(void);