builtin/apply: make gitdiff_verify_name() return void

As the value returned by gitdiff_verify_name() is put into the
same variable that is passed as a parameter to this function,
it is simpler to pass the address of the variable and have
gitdiff_verify_name() change the variable itself.

This also makes it possible to later have this function return
-1 instead of die()ing in case of error.

Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/apply.c

@@ -925,43 +925,43 @@ static int gitdiff_hdrend(const char *line, struct patch *patch)
 #define DIFF_OLD_NAME 0
 #define DIFF_NEW_NAME 1
 
-static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, int side)
+static void gitdiff_verify_name(const char *line, int isnull, char **name, int side)
 {
-	if (!orig_name && !isnull)
-		return find_name(line, NULL, p_value, TERM_TAB);
+	if (!*name && !isnull) {
+		*name = find_name(line, NULL, p_value, TERM_TAB);
+		return;
+	}
 
-	if (orig_name) {
-		int len = strlen(orig_name);
+	if (*name) {
+		int len = strlen(*name);
 		char *another;
 		if (isnull)
 			die(_("git apply: bad git-diff - expected /dev/null, got %s on line %d"),
-			    orig_name, linenr);
+			    *name, linenr);
 		another = find_name(line, NULL, p_value, TERM_TAB);
-		if (!another || memcmp(another, orig_name, len + 1))
+		if (!another || memcmp(another, *name, len + 1))
 			die((side == DIFF_NEW_NAME) ?
 			    _("git apply: bad git-diff - inconsistent new filename on line %d") :
 			    _("git apply: bad git-diff - inconsistent old filename on line %d"), linenr);
 		free(another);
-		return orig_name;
 	} else {
 		/* expect "/dev/null" */
 		if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 			die(_("git apply: bad git-diff - expected /dev/null on line %d"), linenr);
-		return NULL;
 	}
 }
 
 static int gitdiff_oldname(const char *line, struct patch *patch)
 {
-	patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name,
-					      DIFF_OLD_NAME);
+	gitdiff_verify_name(line, patch->is_new, &patch->old_name,
+			    DIFF_OLD_NAME);
 	return 0;
 }
 
 static int gitdiff_newname(const char *line, struct patch *patch)
 {
-	patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name,
-					      DIFF_NEW_NAME);
+	gitdiff_verify_name(line, patch->is_delete, &patch->new_name,
+			    DIFF_NEW_NAME);
 	return 0;
 }