char *a_one, *b_two;
const char *set = diff_get_color_opt(o, DIFF_METAINFO);
const char *reset = diff_get_color_opt(o, DIFF_RESET);
+ const char *a_prefix, *b_prefix;
+
+ diff_set_mnemonic_prefix(o, "a/", "b/");
+ if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
+ a_prefix = o->b_prefix;
+ b_prefix = o->a_prefix;
+ } else {
+ a_prefix = o->a_prefix;
+ b_prefix = o->b_prefix;
+ }
- a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
- b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
+ /* Never use a non-valid filename anywhere if at all possible */
+ name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
+ name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
+
+ a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
+ b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);