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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* hash.c
*
* This is merely a couple wrappers around NSPR's PLHashTable, using
* the identity hash and arena-aware allocators.
* This is a copy of ckfw/hash.c, with modifications to use NSS types
* (not Cryptoki types). Would like for this to be a single implementation,
* but doesn't seem like it will work.
*/
#ifndef BASE_H
#include "base.h"
#endif /* BASE_H */
#include "prbit.h"
/*
* nssHash
*
* nssHash_Create
* nssHash_Destroy
* nssHash_Add
* nssHash_Remove
* nssHash_Count
* nssHash_Exists
* nssHash_Lookup
* nssHash_Iterate
*/
struct nssHashStr {
NSSArena *arena;
PRBool i_alloced_arena;
PRLock *mutex;
/*
* The invariant that mutex protects is:
* The count accurately reflects the hashtable state.
*/
PLHashTable *plHashTable;
PRUint32 count;
};
static PLHashNumber
nss_identity_hash(const void *key)
{
return (PLHashNumber)((char *)key - (char *)NULL);
}
static PLHashNumber
nss_item_hash(const void *key)
{
unsigned int i;
PLHashNumber h;
NSSItem *it = (NSSItem *)key;
h = 0;
for (i = 0; i < it->size; i++)
h = PR_ROTATE_LEFT32(h, 4) ^ ((unsigned char *)it->data)[i];
return h;
}
static int
nss_compare_items(const void *v1, const void *v2)
{
PRStatus ignore;
return (int)nssItem_Equal((NSSItem *)v1, (NSSItem *)v2, &ignore);
}
/*
* nssHash_create
*
*/
NSS_IMPLEMENT nssHash *
nssHash_Create(NSSArena *arenaOpt, PRUint32 numBuckets, PLHashFunction keyHash,
PLHashComparator keyCompare, PLHashComparator valueCompare)
{
nssHash *rv;
NSSArena *arena;
PRBool i_alloced;
#ifdef NSSDEBUG
if (arenaOpt && PR_SUCCESS != nssArena_verifyPointer(arenaOpt)) {
nss_SetError(NSS_ERROR_INVALID_POINTER);
return (nssHash *)NULL;
}
#endif /* NSSDEBUG */
if (arenaOpt) {
arena = arenaOpt;
i_alloced = PR_FALSE;
} else {
arena = nssArena_Create();
i_alloced = PR_TRUE;
}
rv = nss_ZNEW(arena, nssHash);
if ((nssHash *)NULL == rv) {
goto loser;
}
rv->mutex = PZ_NewLock(nssILockOther);
if ((PZLock *)NULL == rv->mutex) {
goto loser;
}
rv->plHashTable =
PL_NewHashTable(numBuckets, keyHash, keyCompare, valueCompare,
&nssArenaHashAllocOps, arena);
if ((PLHashTable *)NULL == rv->plHashTable) {
(void)PZ_DestroyLock(rv->mutex);
goto loser;
}
rv->count = 0;
rv->arena = arena;
rv->i_alloced_arena = i_alloced;
return rv;
loser:
(void)nss_ZFreeIf(rv);
return (nssHash *)NULL;
}
/*
* nssHash_CreatePointer
*
*/
NSS_IMPLEMENT nssHash *
nssHash_CreatePointer(NSSArena *arenaOpt, PRUint32 numBuckets)
{
return nssHash_Create(arenaOpt, numBuckets, nss_identity_hash,
PL_CompareValues, PL_CompareValues);
}
/*
* nssHash_CreateString
*
*/
NSS_IMPLEMENT nssHash *
nssHash_CreateString(NSSArena *arenaOpt, PRUint32 numBuckets)
{
return nssHash_Create(arenaOpt, numBuckets, PL_HashString,
PL_CompareStrings, PL_CompareStrings);
}
/*
* nssHash_CreateItem
*
*/
NSS_IMPLEMENT nssHash *
nssHash_CreateItem(NSSArena *arenaOpt, PRUint32 numBuckets)
{
return nssHash_Create(arenaOpt, numBuckets, nss_item_hash,
nss_compare_items, PL_CompareValues);
}
/*
* nssHash_Destroy
*
*/
NSS_IMPLEMENT void
nssHash_Destroy(nssHash *hash)
{
(void)PZ_DestroyLock(hash->mutex);
PL_HashTableDestroy(hash->plHashTable);
if (hash->i_alloced_arena) {
nssArena_Destroy(hash->arena);
} else {
nss_ZFreeIf(hash);
}
}
/*
* nssHash_Add
*
*/
NSS_IMPLEMENT PRStatus
nssHash_Add(nssHash *hash, const void *key, const void *value)
{
PRStatus error = PR_FAILURE;
PLHashEntry *he;
PZ_Lock(hash->mutex);
he = PL_HashTableAdd(hash->plHashTable, key, (void *)value);
if ((PLHashEntry *)NULL == he) {
nss_SetError(NSS_ERROR_NO_MEMORY);
} else if (he->value != value) {
nss_SetError(NSS_ERROR_HASH_COLLISION);
} else {
hash->count++;
error = PR_SUCCESS;
}
(void)PZ_Unlock(hash->mutex);
return error;
}
/*
* nssHash_Remove
*
*/
NSS_IMPLEMENT void
nssHash_Remove(nssHash *hash, const void *it)
{
PRBool found;
PZ_Lock(hash->mutex);
found = PL_HashTableRemove(hash->plHashTable, it);
if (found) {
hash->count--;
}
(void)PZ_Unlock(hash->mutex);
return;
}
/*
* nssHash_Count
*
*/
NSS_IMPLEMENT PRUint32
nssHash_Count(nssHash *hash)
{
PRUint32 count;
PZ_Lock(hash->mutex);
count = hash->count;
(void)PZ_Unlock(hash->mutex);
return count;
}
/*
* nssHash_Exists
*
*/
NSS_IMPLEMENT PRBool
nssHash_Exists(nssHash *hash, const void *it)
{
void *value;
PZ_Lock(hash->mutex);
value = PL_HashTableLookup(hash->plHashTable, it);
(void)PZ_Unlock(hash->mutex);
if ((void *)NULL == value) {
return PR_FALSE;
} else {
return PR_TRUE;
}
}
/*
* nssHash_Lookup
*
*/
NSS_IMPLEMENT void *
nssHash_Lookup(nssHash *hash, const void *it)
{
void *rv;
PZ_Lock(hash->mutex);
rv = PL_HashTableLookup(hash->plHashTable, it);
(void)PZ_Unlock(hash->mutex);
return rv;
}
struct arg_str {
nssHashIterator fcn;
void *closure;
};
static PRIntn
nss_hash_enumerator(PLHashEntry *he, PRIntn index, void *arg)
{
struct arg_str *as = (struct arg_str *)arg;
as->fcn(he->key, he->value, as->closure);
return HT_ENUMERATE_NEXT;
}
/*
* nssHash_Iterate
*
* NOTE that the iteration function will be called with the hashtable locked.
*/
NSS_IMPLEMENT void
nssHash_Iterate(nssHash *hash, nssHashIterator fcn, void *closure)
{
struct arg_str as;
as.fcn = fcn;
as.closure = closure;
PZ_Lock(hash->mutex);
PL_HashTableEnumerateEntries(hash->plHashTable, nss_hash_enumerator, &as);
(void)PZ_Unlock(hash->mutex);
return;
}