commit: -F overrides -t

Commit dbd0f5c (Files given on the command line are relative to $cwd,
2008-08-06) introduced parse_options_fix_filename() as a quick fix for
filename arguments used in the parse options API.

git-commit was still broken. This means

    git commit -F log -t temp

in a subdirectory would make git think the log message should be taken
from temp instead of log.

This is because parse_options_fix_filename() calls prefix_filename()
which uses a single static char buffer to do its work. Making two calls
with two char pointers causes the pointers to alias. To prevent
aliasing, we duplicate the string returned by
parse_options_fix_filename().

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-commit.c

@@ -699,7 +699,11 @@ static int parse_and_validate_options(int argc, const char *argv[],
 
 	argc = parse_options(argc, argv, builtin_commit_options, usage, 0);
 	logfile = parse_options_fix_filename(prefix, logfile);
+	if (logfile)
+		logfile = xstrdup(logfile);
 	template_file = parse_options_fix_filename(prefix, template_file);
+	if (template_file)
+		template_file = xstrdup(template_file);
 
 	if (force_author && !strchr(force_author, '>'))
 		force_author = find_author_by_nickname(force_author);

t/t7500-commit.sh

@@ -183,4 +183,14 @@ test_expect_success 'commit message from stdin' '
 	commit_msg_is "Log with foo word"
 '
 
+test_expect_success 'commit -F overrides -t' '
+	(
+		cd subdir &&
+		echo "-F log" > f.log &&
+		echo "-t template" > t.template &&
+		git commit --allow-empty -F f.log -t t.template
+	) &&
+	commit_msg_is "-F log"
+'
+
 test_done