int
icdb_rehash(struct icdb *db)
{
struct icdbinfo *info = db->info;
uint32_t entrysize = info->entrysize;
uint32_t indexsize, idxmask, idxlen;
int i, j;
indexsize = info->indexsize = roundup(info->nentries);
idxmask = indexsize - 1;
idxlen = sizeof(uint32_t) * indexsize;
arc4random_buf(&info->siphashkey, sizeof(info->siphashkey));
for (i = 0; i < info->nkeys; i++) {
uint32_t *idxdata = reallocarray(db->idxdata[i],
indexsize, sizeof(uint32_t));
if (!idxdata)
return -1;
memset(idxdata, 0xff, idxlen);
db->idxdata[i] = idxdata;
}
for (j = 0; j < info->nentries; j++) {
for (i = 0; i < info->nkeys; i++) {
uint32_t *idxdata = db->idxdata[i];
uint64_t hash = SipHash24(&info->siphashkey,
(uint8_t *)db->entries + j * entrysize +
info->keyoffset[i], info->keysize[i]);
while (idxdata[hash & idxmask] != -1)
hash = SipHash24(&info->siphashkey, &hash, sizeof(hash));
idxdata[hash & idxmask] = j;
}
}
return 0;
}
int
icdb_lookup(struct icdb *db, int keynum, const void *key, void *entry,
uint32_t *idxp)
{
struct icdbinfo *info = db->info;
uint32_t offset;
uint64_t hash;
uint32_t indexsize, idxmask, idxlen;
uint32_t *idxdata;
indexsize = info->indexsize;
idxmask = indexsize - 1;
idxlen = indexsize * sizeof(uint32_t);
idxdata = db->idxdata[keynum];
hash = SipHash24(&info->siphashkey, key, info->keysize[keynum]);
while ((offset = idxdata[hash & idxmask]) != -1) {
if (icdb_get(db, entry, offset) != 0) {
errno = ENOENT;
return -1;
}
if (memcmp((uint8_t *)entry + info->keyoffset[keynum], key,
info->keysize[keynum]) == 0) {
if (idxp)
*idxp = offset;
return 0;
}
hash = SipHash24(&info->siphashkey, &hash, sizeof(hash));
}
return 1;
}
/*
* Hash the specified filename into a dirhash slot.
*/
int
ufsdirhash_hash(struct dirhash *dh, char *name, int namelen)
{
return SipHash24(&ufsdirhash_key, name, namelen) % dh->dh_hlen;
}
