dir: introduce readdir_skip_dot_and_dotdot() helper

Many places in the code were doing
    while ((d = readdir(dir)) != NULL) {
        if (is_dot_or_dotdot(d->d_name))
            continue;
        ...process d...
    }
Introduce a readdir_skip_dot_and_dotdot() helper to make that a one-liner:
    while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
        ...process d...
    }

This helper particularly simplifies checks for empty directories.

Also use this helper in read_cached_dir() so that our statistics are
consistent across platforms.  (In other words, read_cached_dir() should
have been using is_dot_or_dotdot() and skipping such entries, but did
not and left it to treat_path() to detect and mark such entries as
path_none.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 9 deletions

diff --git a/worktree.c b/worktree.c
index f35ac40..237517b 100644
--- a/worktree.c
+++ b/worktree.c
@@ -128,10 +128,8 @@ struct worktree **get_worktrees(void)
 	dir = opendir(path.buf);
 	strbuf_release(&path);
 	if (dir) {
-		while ((d = readdir(dir)) != NULL) {
+		while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
 			struct worktree *linked = NULL;
-			if (is_dot_or_dotdot(d->d_name))
-				continue;
 
 			if ((linked = get_linked_worktree(d->d_name))) {
 				ALLOC_GROW(list, counter + 1, alloc);
@@ -486,13 +484,9 @@ int submodule_uses_worktrees(const char *path)
 	if (!dir)
 		return 0;
 
-	while ((d = readdir(dir)) != NULL) {
-		if (is_dot_or_dotdot(d->d_name))
-			continue;
-
+	d = readdir_skip_dot_and_dotdot(dir);
+	if (d != NULL)
 		ret = 1;
-		break;
-	}
 	closedir(dir);
 	return ret;
 }