diff options
| -rw-r--r-- | merge-recursive.c | 60 |
1 files changed, 36 insertions, 24 deletions
diff --git a/merge-recursive.c b/merge-recursive.c index 22a12cfeba..f80e48f623 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -1943,8 +1943,8 @@ static void get_renamed_dir_portion(const char *old_path, const char *new_path, char **old_dir, char **new_dir) { char *end_of_old, *end_of_new; - int old_len, new_len; + /* Default return values: NULL, meaning no rename */ *old_dir = NULL; *new_dir = NULL; @@ -1955,43 +1955,55 @@ static void get_renamed_dir_portion(const char *old_path, const char *new_path, * "a/b/c/d" was renamed to "a/b/some/thing/else" * so, for this example, this function returns "a/b/c/d" in * *old_dir and "a/b/some/thing/else" in *new_dir. - * - * Also, if the basename of the file changed, we don't care. We - * want to know which portion of the directory, if any, changed. + */ + + /* + * If the basename of the file changed, we don't care. We want + * to know which portion of the directory, if any, changed. */ end_of_old = strrchr(old_path, '/'); end_of_new = strrchr(new_path, '/'); - if (end_of_old == NULL || end_of_new == NULL) - return; + return; /* We haven't modified *old_dir or *new_dir yet. */ + + /* Find the first non-matching character traversing backwards */ while (*--end_of_new == *--end_of_old && end_of_old != old_path && end_of_new != new_path) ; /* Do nothing; all in the while loop */ + /* - * We've found the first non-matching character in the directory - * paths. That means the current directory we were comparing - * represents the rename. Move end_of_old and end_of_new back - * to the full directory name. + * If both got back to the beginning of their strings, then the + * directory didn't change at all, only the basename did. */ - if (*end_of_old == '/') - end_of_old++; - if (*end_of_old != '/') - end_of_new++; - end_of_old = strchr(end_of_old, '/'); - end_of_new = strchr(end_of_new, '/'); + if (end_of_old == old_path && end_of_new == new_path && + *end_of_old == *end_of_new) + return; /* We haven't modified *old_dir or *new_dir yet. */ /* - * It may have been the case that old_path and new_path were the same - * directory all along. Don't claim a rename if they're the same. + * We've found the first non-matching character in the directory + * paths. That means the current characters we were looking at + * were part of the first non-matching subdir name going back from + * the end of the strings. Get the whole name by advancing both + * end_of_old and end_of_new to the NEXT '/' character. That will + * represent the entire directory rename. + * + * The reason for the increment is cases like + * a/b/star/foo/whatever.c -> a/b/tar/foo/random.c + * After dropping the basename and going back to the first + * non-matching character, we're now comparing: + * a/b/s and a/b/ + * and we want to be comparing: + * a/b/star/ and a/b/tar/ + * but without the pre-increment, the one on the right would stay + * a/b/. */ - old_len = end_of_old - old_path; - new_len = end_of_new - new_path; + end_of_old = strchr(++end_of_old, '/'); + end_of_new = strchr(++end_of_new, '/'); - if (old_len != new_len || strncmp(old_path, new_path, old_len)) { - *old_dir = xstrndup(old_path, old_len); - *new_dir = xstrndup(new_path, new_len); - } + /* Copy the old and new directories into *old_dir and *new_dir. */ + *old_dir = xstrndup(old_path, end_of_old - old_path); + *new_dir = xstrndup(new_path, end_of_new - new_path); } static void remove_hashmap_entries(struct hashmap *dir_renames, |