+/*
+ * Check a single reachable object
+ */
+static void check_reachable_object(struct object *obj)
+{
+ const struct object_refs *refs;
+
+ /*
+ * We obviously want the object to be parsed,
+ * except if it was in a pack-file and we didn't
+ * do a full fsck
+ */
+ if (!obj->parsed) {
+ if (has_sha1_file(obj->sha1))
+ return; /* it is in pack - forget about it */
+ printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+ return;
+ }
+
+ /*
+ * Check that everything that we try to reference is also good.
+ */
+ refs = lookup_object_refs(obj);
+ if (refs) {
+ unsigned j;
+ for (j = 0; j < refs->count; j++) {
+ struct object *ref = refs->ref[j];
+ if (ref->parsed ||
+ (has_sha1_file(ref->sha1)))
+ continue;
+ printf("broken link from %7s %s\n",
+ typename(obj->type), sha1_to_hex(obj->sha1));
+ printf(" to %7s %s\n",
+ typename(ref->type), sha1_to_hex(ref->sha1));
+ }
+ }
+}
+
+/*
+ * Check a single unreachable object
+ */
+static void check_unreachable_object(struct object *obj)
+{
+ /*
+ * Missing unreachable object? Ignore it. It's not like
+ * we miss it (since it can't be reached), nor do we want
+ * to complain about it being unreachable (since it does
+ * not exist).
+ */
+ if (!obj->parsed)
+ return;
+
+ /*
+ * Unreachable object that exists? Show it if asked to,
+ * since this is something that is prunable.
+ */
+ if (show_unreachable) {
+ printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+ return;
+ }
+
+ /*
+ * "!used" means that nothing at all points to it, including
+ * other unreacahble objects. In other words, it's the "tip"
+ * of some set of unreachable objects, usually a commit that
+ * got dropped.
+ *
+ * Such starting points are more interesting than some random
+ * set of unreachable objects, so we show them even if the user
+ * hasn't asked for _all_ unreachable objects. If you have
+ * deleted a branch by mistake, this is a prime candidate to
+ * start looking at, for example.
+ */
+ if (!obj->used) {
+ printf("dangling %s %s\n", typename(obj->type),
+ sha1_to_hex(obj->sha1));
+ return;
+ }
+
+ /*
+ * Otherwise? It's there, it's unreachable, and some other unreachable
+ * object points to it. Ignore it - it's not interesting, and we showed
+ * all the interesting cases above.
+ */
+}
+
+static void check_object(struct object *obj)
+{
+ if (obj->flags & REACHABLE)
+ check_reachable_object(obj);
+ else
+ check_unreachable_object(obj);
+}