+static void prepare_show_merge(struct rev_info *revs)
+{
+ struct commit_list *bases;
+ struct commit *head, *other;
+ unsigned char sha1[20];
+ const char **prune = NULL;
+ int i, prune_num = 1; /* counting terminating NULL */
+
+ if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
+ die("--merge without HEAD?");
+ if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
+ die("--merge without MERGE_HEAD?");
+ add_pending_object(revs, &head->object, "HEAD");
+ add_pending_object(revs, &other->object, "MERGE_HEAD");
+ bases = get_merge_bases(head, other, 1);
+ while (bases) {
+ struct commit *it = bases->item;
+ struct commit_list *n = bases->next;
+ free(bases);
+ bases = n;
+ it->object.flags |= UNINTERESTING;
+ add_pending_object(revs, &it->object, "(merge-base)");
+ }
+
+ if (!active_nr)
+ read_cache();
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ if (!ce_stage(ce))
+ continue;
+ if (ce_path_match(ce, revs->prune_data)) {
+ prune_num++;
+ prune = xrealloc(prune, sizeof(*prune) * prune_num);
+ prune[prune_num-2] = ce->name;
+ prune[prune_num-1] = NULL;
+ }
+ while ((i+1 < active_nr) &&
+ ce_same_name(ce, active_cache[i+1]))
+ i++;
+ }
+ revs->prune_data = prune;
+}
+