static void cmp_two_packs(struct pack_list *p1, struct pack_list *p2)
{
unsigned long p1_off = 0, p2_off = 0, p1_step, p2_step;
const unsigned char *p1_base, *p2_base;
struct llist_item *p1_hint = NULL, *p2_hint = NULL;
p1_base = p1->pack->index_data;
p2_base = p2->pack->index_data;
p1_base += 256 * 4 + ((p1->pack->index_version < 2) ? 4 : 8);
p2_base += 256 * 4 + ((p2->pack->index_version < 2) ? 4 : 8);
p1_step = (p1->pack->index_version < 2) ? 24 : 20;
p2_step = (p2->pack->index_version < 2) ? 24 : 20;
while (p1_off < p1->pack->num_objects * p1_step &&
p2_off < p2->pack->num_objects * p2_step)
{
int cmp = hashcmp(p1_base + p1_off, p2_base + p2_off);
/* cmp ~ p1 - p2 */
if (cmp == 0) {
p1_hint = llist_sorted_remove(p1->unique_objects,
p1_base + p1_off, p1_hint);
p2_hint = llist_sorted_remove(p2->unique_objects,
p1_base + p1_off, p2_hint);
p1_off += p1_step;
p2_off += p2_step;
continue;
}
if (cmp < 0) { /* p1 has the object, p2 doesn't */
p1_off += p1_step;
} else { /* p2 has the object, p1 doesn't */
p2_off += p2_step;
}
}
}
/* computes A\B */
static void llist_sorted_difference_inplace(struct llist *A,
struct llist *B)
{
struct llist_item *hint, *b;
hint = NULL;
b = B->front;
while (b) {
hint = llist_sorted_remove(A, b->oid, hint);
b = b->next;
}
}
