ident: split setup_ident into separate functions

This function sets up the default name, email, and date, and
is not publicly available. Let's split it into three public
functions so that callers can get just the parts they need.

While we're at it, let's change the interface to simple
accessors. The original function was called only by fmt_ident,
and contained logic for "if we already have some other
value, don't load the default" which properly belongs in
fmt_ident.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

cache.h

@@ -894,6 +894,9 @@ extern const char *git_author_info(int);
 extern const char *git_committer_info(int);
 extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
 extern const char *fmt_name(const char *name, const char *email);
+extern const char *ident_default_name(void);
+extern const char *ident_default_email(void);
+extern const char *ident_default_date(void);
 extern const char *git_editor(void);
 extern const char *git_pager(int stdout_is_tty);
 

ident.c

@@ -117,21 +117,20 @@ static void copy_email(const struct passwd *pw)
 			sizeof(git_default_email) - len);
 }
 
-static void setup_ident(const char **name, const char **emailp)
+const char *ident_default_name(void)
 {
-	struct passwd *pw = NULL;
-
-	/* Get the name ("gecos") */
-	if (!*name && !git_default_name[0]) {
-		pw = getpwuid(getuid());
+	if (!git_default_name[0]) {
+		struct passwd *pw = getpwuid(getuid());
 		if (!pw)
 			die("You don't exist. Go away!");
 		copy_gecos(pw, git_default_name, sizeof(git_default_name));
 	}
-	if (!*name)
-		*name = git_default_name;
+	return git_default_name;
+}
 
-	if (!*emailp && !git_default_email[0]) {
+const char *ident_default_email(void)
+{
+	if (!git_default_email[0]) {
 		const char *email = getenv("EMAIL");
 
 		if (email && email[0]) {
@@ -139,19 +138,20 @@ static void setup_ident(const char **name, const char **emailp)
 				sizeof(git_default_email));
 			user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 		} else {
-			if (!pw)
-				pw = getpwuid(getuid());
+			struct passwd *pw = getpwuid(getuid());
 			if (!pw)
 				die("You don't exist. Go away!");
 			copy_email(pw);
 		}
 	}
-	if (!*emailp)
-		*emailp = git_default_email;
+	return git_default_email;
+}
 
-	/* And set the default date */
+const char *ident_default_date(void)
+{
 	if (!git_default_date[0])
 		datestamp(git_default_date, sizeof(git_default_date));
+	return git_default_date;
 }
 
 static int add_raw(char *buf, size_t size, int offset, const char *str)
@@ -311,7 +311,10 @@ const char *fmt_ident(const char *name, const char *email,
 	int warn_on_no_name = (flag & IDENT_WARN_ON_NO_NAME);
 	int name_addr_only = (flag & IDENT_NO_DATE);
 
-	setup_ident(&name, &email);
+	if (!name)
+		name = ident_default_name();
+	if (!email)
+		email = ident_default_email();
 
 	if (!*name) {
 		struct passwd *pw;
@@ -331,7 +334,7 @@ const char *fmt_ident(const char *name, const char *email,
 		name = git_default_name;
 	}
 
-	strcpy(date, git_default_date);
+	strcpy(date, ident_default_date());
 	if (!name_addr_only && date_str && date_str[0]) {
 		if (parse_date(date_str, date, sizeof(date)) < 0)
 			die("invalid date format: %s", date_str);