hash.c
上传用户:lyxiangda
上传日期:2007-01-12
资源大小:3042k
文件大小:6k
- /*
- * The contents of this file are subject to the Mozilla Public
- * License Version 1.1 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of
- * the License at http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS
- * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
- * implied. See the License for the specific language governing
- * rights and limitations under the License.
- *
- * The Original Code is the Netscape security libraries.
- *
- * The Initial Developer of the Original Code is Netscape
- * Communications Corporation. Portions created by Netscape are
- * Copyright (C) 1994-2000 Netscape Communications Corporation. All
- * Rights Reserved.
- *
- * Contributor(s):
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License Version 2 or later (the
- * "GPL"), in which case the provisions of the GPL are applicable
- * instead of those above. If you wish to allow use of your
- * version of this file only under the terms of the GPL and not to
- * allow others to use your version of this file under the MPL,
- * indicate your decision by deleting the provisions above and
- * replace them with the notice and other provisions required by
- * the GPL. If you do not delete the provisions above, a recipient
- * may use your version of this file under either the MPL or the
- * GPL.
- */
- #ifdef DEBUG
- static const char CVS_ID[] = "@(#) $RCSfile: hash.c,v $ $Revision: 1.1 $ $Date: 2000/03/31 19:43:15 $ $Name: NSS_3_1_1_RTM $";
- #endif /* DEBUG */
- /*
- * hash.c
- *
- * This is merely a couple wrappers around NSPR's PLHashTable, using
- * the identity hash and arena-aware allocators. The reason I did
- * this is that hash tables are used in a few places throughout the
- * NSS Cryptoki Framework in a fairly stereotyped way, and this allows
- * me to pull the commonalities into one place. Should we ever want
- * to change the implementation, it's all right here.
- */
- #ifndef CK_T
- #include "ck.h"
- #endif /* CK_T */
- /*
- * nssCKFWHash
- *
- * nssCKFWHash_Create
- * nssCKFWHash_Destroy
- * nssCKFWHash_Add
- * nssCKFWHash_Remove
- * nssCKFWHash_Count
- * nssCKFWHash_Exists
- * nssCKFWHash_Lookup
- * nssCKFWHash_Iterate
- */
- struct nssCKFWHashStr {
- NSSCKFWMutex *mutex;
- /*
- * The invariant that mutex protects is:
- * The count accurately reflects the hashtable state.
- */
- PLHashTable *plHashTable;
- CK_ULONG count;
- };
- static PLHashNumber
- nss_ckfw_identity_hash
- (
- const void *key
- )
- {
- PRUint32 i = (PRUint32)key;
- PR_ASSERT(sizeof(PLHashNumber) == sizeof(PRUint32));
- return (PLHashNumber)i;
- }
- /*
- * nssCKFWHash_Create
- *
- */
- NSS_IMPLEMENT nssCKFWHash *
- nssCKFWHash_Create
- (
- NSSCKFWInstance *fwInstance,
- NSSArena *arena,
- CK_RV *pError
- )
- {
- nssCKFWHash *rv;
- #ifdef NSSDEBUG
- if( (CK_RV *)NULL == pError ) {
- return (nssCKFWHash *)NULL;
- }
- if( PR_SUCCESS != nssArena_verifyPointer(arena) ) {
- *pError = CKR_ARGUMENTS_BAD;
- return (nssCKFWHash *)NULL;
- }
- #endif /* NSSDEBUG */
- rv = nss_ZNEW(arena, nssCKFWHash);
- if( (nssCKFWHash *)NULL == rv ) {
- *pError = CKR_HOST_MEMORY;
- return (nssCKFWHash *)NULL;
- }
- rv->mutex = nssCKFWInstance_CreateMutex(fwInstance, arena, pError);
- if( (NSSCKFWMutex *)NULL == rv->mutex ) {
- if( CKR_OK == *pError ) {
- *pError = CKR_GENERAL_ERROR;
- }
- return (nssCKFWHash *)NULL;
- }
- rv->plHashTable = PL_NewHashTable(0, nss_ckfw_identity_hash,
- PL_CompareValues, PL_CompareValues, &nssArenaHashAllocOps, arena);
- if( (PLHashTable *)NULL == rv->plHashTable ) {
- (void)nssCKFWMutex_Destroy(rv->mutex);
- (void)nss_ZFreeIf(rv);
- *pError = CKR_HOST_MEMORY;
- return (nssCKFWHash *)NULL;
- }
- rv->count = 0;
- return rv;
- }
- /*
- * nssCKFWHash_Destroy
- *
- */
- NSS_IMPLEMENT void
- nssCKFWHash_Destroy
- (
- nssCKFWHash *hash
- )
- {
- (void)nssCKFWMutex_Destroy(hash->mutex);
- PL_HashTableDestroy(hash->plHashTable);
- (void)nss_ZFreeIf(hash);
- }
- /*
- * nssCKFWHash_Add
- *
- */
- NSS_IMPLEMENT CK_RV
- nssCKFWHash_Add
- (
- nssCKFWHash *hash,
- const void *key,
- const void *value
- )
- {
- CK_RV error = CKR_OK;
- PLHashEntry *he;
- error = nssCKFWMutex_Lock(hash->mutex);
- if( CKR_OK != error ) {
- return error;
- }
-
- he = PL_HashTableAdd(hash->plHashTable, key, (void *)value);
- if( (PLHashEntry *)NULL == he ) {
- error = CKR_HOST_MEMORY;
- } else {
- hash->count++;
- }
- (void)nssCKFWMutex_Unlock(hash->mutex);
- return error;
- }
- /*
- * nssCKFWHash_Remove
- *
- */
- NSS_IMPLEMENT void
- nssCKFWHash_Remove
- (
- nssCKFWHash *hash,
- const void *it
- )
- {
- PRBool found;
- if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
- return;
- }
- found = PL_HashTableRemove(hash->plHashTable, it);
- if( found ) {
- hash->count--;
- }
- (void)nssCKFWMutex_Unlock(hash->mutex);
- return;
- }
- /*
- * nssCKFWHash_Count
- *
- */
- NSS_IMPLEMENT CK_ULONG
- nssCKFWHash_Count
- (
- nssCKFWHash *hash
- )
- {
- CK_ULONG count;
- if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
- return (CK_ULONG)0;
- }
- count = hash->count;
- (void)nssCKFWMutex_Unlock(hash->mutex);
- return count;
- }
- /*
- * nssCKFWHash_Exists
- *
- */
- NSS_IMPLEMENT CK_BBOOL
- nssCKFWHash_Exists
- (
- nssCKFWHash *hash,
- const void *it
- )
- {
- void *value;
- if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
- return CK_FALSE;
- }
- value = PL_HashTableLookup(hash->plHashTable, it);
- (void)nssCKFWMutex_Unlock(hash->mutex);
- if( (void *)NULL == value ) {
- return CK_FALSE;
- } else {
- return CK_TRUE;
- }
- }
- /*
- * nssCKFWHash_Lookup
- *
- */
- NSS_IMPLEMENT void *
- nssCKFWHash_Lookup
- (
- nssCKFWHash *hash,
- const void *it
- )
- {
- void *rv;
- if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
- return (void *)NULL;
- }
- rv = PL_HashTableLookup(hash->plHashTable, it);
- (void)nssCKFWMutex_Unlock(hash->mutex);
- return rv;
- }
- struct arg_str {
- nssCKFWHashIterator fcn;
- void *closure;
- };
- static PRIntn
- nss_ckfwhash_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;
- }
- /*
- * nssCKFWHash_Iterate
- *
- * NOTE that the iteration function will be called with the hashtable locked.
- */
- NSS_IMPLEMENT void
- nssCKFWHash_Iterate
- (
- nssCKFWHash *hash,
- nssCKFWHashIterator fcn,
- void *closure
- )
- {
- struct arg_str as;
- as.fcn = fcn;
- as.closure = closure;
- if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
- return;
- }
- PL_HashTableEnumerateEntries(hash->plHashTable, nss_ckfwhash_enumerator, &as);
- (void)nssCKFWMutex_Unlock(hash->mutex);
- return;
- }