| /* |
| * A wrapper around cbtree which stores oids |
| * May be used to replace oid-array for prefix (abbreviation) matches |
| */ |
| #include "git-compat-util.h" |
| #include "oidtree.h" |
| #include "hash.h" |
| |
| struct oidtree_iter_data { |
| oidtree_iter fn; |
| void *arg; |
| size_t *last_nibble_at; |
| int algo; |
| uint8_t last_byte; |
| }; |
| |
| void oidtree_init(struct oidtree *ot) |
| { |
| cb_init(&ot->tree); |
| mem_pool_init(&ot->mem_pool, 0); |
| } |
| |
| void oidtree_clear(struct oidtree *ot) |
| { |
| if (ot) { |
| mem_pool_discard(&ot->mem_pool, 0); |
| oidtree_init(ot); |
| } |
| } |
| |
| void oidtree_insert(struct oidtree *ot, const struct object_id *oid) |
| { |
| struct cb_node *on; |
| struct object_id k; |
| |
| if (!oid->algo) |
| BUG("oidtree_insert requires oid->algo"); |
| |
| on = mem_pool_alloc(&ot->mem_pool, sizeof(*on) + sizeof(*oid)); |
| |
| /* |
| * Clear the padding and copy the result in separate steps to |
| * respect the 4-byte alignment needed by struct object_id. |
| */ |
| oidcpy(&k, oid); |
| memcpy(on->k, &k, sizeof(k)); |
| |
| /* |
| * n.b. Current callers won't get us duplicates, here. If a |
| * future caller causes duplicates, there'll be a a small leak |
| * that won't be freed until oidtree_clear. Currently it's not |
| * worth maintaining a free list |
| */ |
| cb_insert(&ot->tree, on, sizeof(*oid)); |
| } |
| |
| |
| int oidtree_contains(struct oidtree *ot, const struct object_id *oid) |
| { |
| struct object_id k; |
| size_t klen = sizeof(k); |
| |
| oidcpy(&k, oid); |
| |
| if (oid->algo == GIT_HASH_UNKNOWN) |
| klen -= sizeof(oid->algo); |
| |
| /* cb_lookup relies on memcmp on the struct, so order matters: */ |
| klen += BUILD_ASSERT_OR_ZERO(offsetof(struct object_id, hash) < |
| offsetof(struct object_id, algo)); |
| |
| return cb_lookup(&ot->tree, (const uint8_t *)&k, klen) ? 1 : 0; |
| } |
| |
| static enum cb_next iter(struct cb_node *n, void *arg) |
| { |
| struct oidtree_iter_data *x = arg; |
| struct object_id k; |
| |
| /* Copy to provide 4-byte alignment needed by struct object_id. */ |
| memcpy(&k, n->k, sizeof(k)); |
| |
| if (x->algo != GIT_HASH_UNKNOWN && x->algo != k.algo) |
| return CB_CONTINUE; |
| |
| if (x->last_nibble_at) { |
| if ((k.hash[*x->last_nibble_at] ^ x->last_byte) & 0xf0) |
| return CB_CONTINUE; |
| } |
| |
| return x->fn(&k, x->arg); |
| } |
| |
| void oidtree_each(struct oidtree *ot, const struct object_id *oid, |
| size_t oidhexsz, oidtree_iter fn, void *arg) |
| { |
| size_t klen = oidhexsz / 2; |
| struct oidtree_iter_data x = { 0 }; |
| assert(oidhexsz <= GIT_MAX_HEXSZ); |
| |
| x.fn = fn; |
| x.arg = arg; |
| x.algo = oid->algo; |
| if (oidhexsz & 1) { |
| x.last_byte = oid->hash[klen]; |
| x.last_nibble_at = &klen; |
| } |
| cb_each(&ot->tree, (const uint8_t *)oid, klen, iter, &x); |
| } |