+/*
+ * Push a level in the iter stack and initialize it with information from
+ * the directory pointed by iter->base->path. It is assumed that this
+ * strbuf points to a valid directory path. Return 0 on success and -1
+ * otherwise, setting errno accordingly and leaving the stack unchanged.
+ */
+static int push_level(struct dir_iterator_int *iter)
+{
+ struct dir_iterator_level *level;
+
+ ALLOC_GROW(iter->levels, iter->levels_nr + 1, iter->levels_alloc);
+ level = &iter->levels[iter->levels_nr++];
+
+ if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1]))
+ strbuf_addch(&iter->base.path, '/');
+ level->prefix_len = iter->base.path.len;
+
+ level->dir = opendir(iter->base.path.buf);
+ if (!level->dir) {
+ int saved_errno = errno;
+ if (errno != ENOENT) {
+ warning_errno("error opening directory '%s'",
+ iter->base.path.buf);
+ }
+ iter->levels_nr--;
+ errno = saved_errno;
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Pop the top level on the iter stack, releasing any resources associated
+ * with it. Return the new value of iter->levels_nr.
+ */
+static int pop_level(struct dir_iterator_int *iter)
+{
+ struct dir_iterator_level *level =
+ &iter->levels[iter->levels_nr - 1];
+
+ if (level->dir && closedir(level->dir))
+ warning_errno("error closing directory '%s'",
+ iter->base.path.buf);
+ level->dir = NULL;
+
+ return --iter->levels_nr;
+}
+
+/*
+ * Populate iter->base with the necessary information on the next iteration
+ * entry, represented by the given dirent de. Return 0 on success and -1
+ * otherwise, setting errno accordingly.
+ */
+static int prepare_next_entry_data(struct dir_iterator_int *iter,
+ struct dirent *de)
+{
+ int err, saved_errno;
+
+ strbuf_addstr(&iter->base.path, de->d_name);
+ /*
+ * We have to reset these because the path strbuf might have
+ * been realloc()ed at the previous strbuf_addstr().
+ */
+ iter->base.relative_path = iter->base.path.buf +
+ iter->levels[0].prefix_len;
+ iter->base.basename = iter->base.path.buf +
+ iter->levels[iter->levels_nr - 1].prefix_len;
+
+ if (iter->flags & DIR_ITERATOR_FOLLOW_SYMLINKS)
+ err = stat(iter->base.path.buf, &iter->base.st);
+ else
+ err = lstat(iter->base.path.buf, &iter->base.st);
+
+ saved_errno = errno;
+ if (err && errno != ENOENT)
+ warning_errno("failed to stat '%s'", iter->base.path.buf);
+
+ errno = saved_errno;
+ return err;
+}
+