+static struct tree_entry_list *find_entry_0(struct tree_entry_list *elem,
+ const char *path,
+ const char *path_end)
+{
+ const char *ep;
+ int len;
+
+ while (path < path_end) {
+ if (prepare_children(elem))
+ return NULL;
+
+ /* In elem->tree->entries, find the one that has name
+ * that matches what is between path and ep.
+ */
+ elem = elem->item.tree->entries;
+
+ ep = strchr(path, '/');
+ if (!ep || path_end <= ep)
+ ep = path_end;
+ len = ep - path;
+
+ while (elem) {
+ if ((strlen(elem->name) == len) &&
+ !strncmp(elem->name, path, len))
+ break;
+ elem = elem->next;
+ }
+ if (path_end <= ep || !elem)
+ return elem;
+ while (*ep == '/' && ep < path_end)
+ ep++;
+ path = ep;
+ }
+ return NULL;
+}
+
+static struct tree_entry_list *find_entry(const char *path,
+ const char *path_end)
+{
+ /* Find tree element, descending from root, that
+ * corresponds to the named path, lazily expanding
+ * the tree if possible.
+ */
+ if (path == path_end) {
+ /* Special. This is the root level */
+ return &root_entry;
+ }
+ return find_entry_0(&root_entry, path, path_end);
+}
+
+static void show_entry_name(struct tree_entry_list *e)
+{
+ /* This is yucky. The root level is there for
+ * our convenience but we really want to do a
+ * forest.
+ */
+ if (e->parent && e->parent != &root_entry) {
+ show_entry_name(e->parent);
+ putchar('/');
+ }
+ printf("%s", e->name);
+}
+
+static const char *entry_type(struct tree_entry_list *e)
+{
+ return (e->directory ? "tree" : "blob");
+}
+
+static const char *entry_hex(struct tree_entry_list *e)
+{
+ return sha1_to_hex(e->directory
+ ? e->item.tree->object.sha1
+ : e->item.blob->object.sha1);
+}
+
+/* forward declaration for mutually recursive routines */
+static int show_entry(struct tree_entry_list *, int);
+
+static int show_children(struct tree_entry_list *e, int level)
+{
+ if (prepare_children(e))
+ die("internal error: ls-tree show_children called with non tree");
+ e = e->item.tree->entries;
+ while (e) {
+ show_entry(e, level);
+ e = e->next;
+ }
+ return 0;
+}
+
+static int show_entry(struct tree_entry_list *e, int level)
+{
+ int err = 0;
+
+ if (e != &root_entry) {
+ printf("%06o %s %s ", e->mode, entry_type(e),
+ entry_hex(e));
+ show_entry_name(e);
+ putchar(line_termination);
+ }
+
+ if (e->directory) {
+ /* If this is a directory, we have the following cases:
+ * (1) This is the top-level request (explicit path from the
+ * command line, or "root" if there is no command line).
+ * a. Without any flag. We show direct children. We do not
+ * recurse into them.
+ * b. With -r. We do recurse into children.
+ * c. With -d. We do not recurse into children.
+ * (2) We came here because our caller is either (1-a) or
+ * (1-b).
+ * a. Without any flag. We do not show our children (which
+ * are grandchildren for the original request).
+ * b. With -r. We continue to recurse into our children.
+ * c. With -d. We should not have come here to begin with.
+ */
+ if (level == 0 && !(ls_options & LS_TREE_ONLY))
+ /* case (1)-a and (1)-b */
+ err = err | show_children(e, level+1);
+ else if (level && ls_options & LS_RECURSIVE)
+ /* case (2)-b */
+ err = err | show_children(e, level+1);
+ }
+ return err;
+}
+
+static int list_one(const char *path, const char *path_end)
+{
+ int err = 0;
+ struct tree_entry_list *e = find_entry(path, path_end);
+ if (!e) {
+ /* traditionally ls-tree does not complain about
+ * missing path. We may change this later to match
+ * what "/bin/ls -a" does, which is to complain.
+ */
+ return err;
+ }
+ err = err | show_entry(e, 0);
+ return err;
+}
+
+static int list(char **path)
+{
+ int i;
+ int err = 0;
+ for (i = 0; path[i]; i++) {
+ int len = strlen(path[i]);
+ while (0 <= len && path[i][len] == '/')
+ len--;
+ err = err | list_one(path[i], path[i] + len);
+ }
+ return err;
+}
+
+static const char *ls_tree_usage =
+ "git-ls-tree [-d] [-r] [-z] <tree-ish> [path...]";
+