+/*
+ * This is a truly stupid algorithm, but it's only
+ * used for bisection, and we just don't care enough.
+ *
+ * We care just barely enough to avoid recursing for
+ * non-merge entries.
+ */
+static int count_distance(struct commit_list *entry)
+{
+ int nr = 0;
+
+ while (entry) {
+ struct commit *commit = entry->item;
+ struct commit_list *p;
+
+ if (commit->object.flags & (UNINTERESTING | COUNTED))
+ break;
+ nr++;
+ commit->object.flags |= COUNTED;
+ p = commit->parents;
+ entry = p;
+ if (p) {
+ p = p->next;
+ while (p) {
+ nr += count_distance(p);
+ p = p->next;
+ }
+ }
+ }
+ return nr;
+}
+
+static void clear_distance(struct commit_list *list)
+{
+ while (list) {
+ struct commit *commit = list->item;
+ commit->object.flags &= ~COUNTED;
+ list = list->next;
+ }
+}
+
+static struct commit_list *find_bisection(struct commit_list *list)
+{
+ int nr, closest;
+ struct commit_list *p, *best;
+
+ nr = 0;
+ p = list;
+ while (p) {
+ nr++;
+ p = p->next;
+ }
+ closest = 0;
+ best = list;
+
+ p = list;
+ while (p) {
+ int distance = count_distance(p);
+ clear_distance(list);
+ if (nr - distance < distance)
+ distance = nr - distance;
+ if (distance > closest) {
+ best = p;
+ closest = distance;
+ }
+ p = p->next;
+ }
+ if (best)
+ best->next = NULL;
+ return best;
+}
+
+struct commit_list *limit_list(struct commit_list *list)
+{
+ struct commit_list *newlist = NULL;
+ struct commit_list **p = &newlist;
+ do {
+ struct commit *commit = pop_most_recent_commit(&list, SEEN);
+ struct object *obj = &commit->object;
+
+ if (obj->flags & UNINTERESTING) {
+ mark_parents_uninteresting(commit);
+ if (everybody_uninteresting(list))
+ break;
+ continue;
+ }
+ p = &commit_list_insert(commit, p)->next;
+ } while (list);
+ if (bisect_list)
+ newlist = find_bisection(newlist);
+ return newlist;
+}
+
+static enum cmit_fmt get_commit_format(const char *arg)
+{
+ if (!*arg)
+ return CMIT_FMT_DEFAULT;
+ if (!strcmp(arg, "=raw"))
+ return CMIT_FMT_RAW;
+ if (!strcmp(arg, "=medium"))
+ return CMIT_FMT_MEDIUM;
+ if (!strcmp(arg, "=short"))
+ return CMIT_FMT_SHORT;
+ usage(rev_list_usage);
+}
+
+