michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * hash.c
michael@0:  *
michael@0:  * This is merely a couple wrappers around NSPR's PLHashTable, using
michael@0:  * the identity hash and arena-aware allocators.  The reason I did
michael@0:  * this is that hash tables are used in a few places throughout the
michael@0:  * NSS Cryptoki Framework in a fairly stereotyped way, and this allows
michael@0:  * me to pull the commonalities into one place.  Should we ever want
michael@0:  * to change the implementation, it's all right here.
michael@0:  */
michael@0: 
michael@0: #ifndef CK_T
michael@0: #include "ck.h"
michael@0: #endif /* CK_T */
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash
michael@0:  *
michael@0:  *  nssCKFWHash_Create
michael@0:  *  nssCKFWHash_Destroy
michael@0:  *  nssCKFWHash_Add
michael@0:  *  nssCKFWHash_Remove
michael@0:  *  nssCKFWHash_Count
michael@0:  *  nssCKFWHash_Exists
michael@0:  *  nssCKFWHash_Lookup
michael@0:  *  nssCKFWHash_Iterate
michael@0:  */
michael@0: 
michael@0: struct nssCKFWHashStr {
michael@0:   NSSCKFWMutex *mutex;
michael@0: 
michael@0:   /*
michael@0:    * The invariant that mutex protects is:
michael@0:    *   The count accurately reflects the hashtable state.
michael@0:    */
michael@0: 
michael@0:   PLHashTable *plHashTable;
michael@0:   CK_ULONG count;
michael@0: };
michael@0: 
michael@0: static PLHashNumber
michael@0: nss_ckfw_identity_hash
michael@0: (
michael@0:   const void *key
michael@0: )
michael@0: {
michael@0:   PRUint32 i = (PRUint32)key;
michael@0:   PR_ASSERT(sizeof(PLHashNumber) == sizeof(PRUint32));
michael@0:   return (PLHashNumber)i;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Create
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT nssCKFWHash *
michael@0: nssCKFWHash_Create
michael@0: (
michael@0:   NSSCKFWInstance *fwInstance,
michael@0:   NSSArena *arena,
michael@0:   CK_RV *pError
michael@0: )
michael@0: {
michael@0:   nssCKFWHash *rv;
michael@0: 
michael@0: #ifdef NSSDEBUG
michael@0:   if (!pError) {
michael@0:     return (nssCKFWHash *)NULL;
michael@0:   }
michael@0: 
michael@0:   if( PR_SUCCESS != nssArena_verifyPointer(arena) ) {
michael@0:     *pError = CKR_ARGUMENTS_BAD;
michael@0:     return (nssCKFWHash *)NULL;
michael@0:   }
michael@0: #endif /* NSSDEBUG */
michael@0: 
michael@0:   rv = nss_ZNEW(arena, nssCKFWHash);
michael@0:   if (!rv) {
michael@0:     *pError = CKR_HOST_MEMORY;
michael@0:     return (nssCKFWHash *)NULL;
michael@0:   }
michael@0: 
michael@0:   rv->mutex = nssCKFWInstance_CreateMutex(fwInstance, arena, pError);
michael@0:   if (!rv->mutex) {
michael@0:     if( CKR_OK == *pError ) {
michael@0:       (void)nss_ZFreeIf(rv);
michael@0:       *pError = CKR_GENERAL_ERROR;
michael@0:     }
michael@0:     return (nssCKFWHash *)NULL;
michael@0:   }
michael@0: 
michael@0:   rv->plHashTable = PL_NewHashTable(0, nss_ckfw_identity_hash, 
michael@0:     PL_CompareValues, PL_CompareValues, &nssArenaHashAllocOps, arena);
michael@0:   if (!rv->plHashTable) {
michael@0:     (void)nssCKFWMutex_Destroy(rv->mutex);
michael@0:     (void)nss_ZFreeIf(rv);
michael@0:     *pError = CKR_HOST_MEMORY;
michael@0:     return (nssCKFWHash *)NULL;
michael@0:   }
michael@0: 
michael@0:   rv->count = 0;
michael@0: 
michael@0:   return rv;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Destroy
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT void
michael@0: nssCKFWHash_Destroy
michael@0: (
michael@0:   nssCKFWHash *hash
michael@0: )
michael@0: {
michael@0:   (void)nssCKFWMutex_Destroy(hash->mutex);
michael@0:   PL_HashTableDestroy(hash->plHashTable);
michael@0:   (void)nss_ZFreeIf(hash);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Add
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT CK_RV
michael@0: nssCKFWHash_Add
michael@0: (
michael@0:   nssCKFWHash *hash,
michael@0:   const void *key,
michael@0:   const void *value
michael@0: )
michael@0: {
michael@0:   CK_RV error = CKR_OK;
michael@0:   PLHashEntry *he;
michael@0: 
michael@0:   error = nssCKFWMutex_Lock(hash->mutex);
michael@0:   if( CKR_OK != error ) {
michael@0:     return error;
michael@0:   }
michael@0:   
michael@0:   he = PL_HashTableAdd(hash->plHashTable, key, (void *)value);
michael@0:   if (!he) {
michael@0:     error = CKR_HOST_MEMORY;
michael@0:   } else {
michael@0:     hash->count++;
michael@0:   }
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0: 
michael@0:   return error;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Remove
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT void
michael@0: nssCKFWHash_Remove
michael@0: (
michael@0:   nssCKFWHash *hash,
michael@0:   const void *it
michael@0: )
michael@0: {
michael@0:   PRBool found;
michael@0: 
michael@0:   if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   found = PL_HashTableRemove(hash->plHashTable, it);
michael@0:   if( found ) {
michael@0:     hash->count--;
michael@0:   }
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0:   return;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Count
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT CK_ULONG
michael@0: nssCKFWHash_Count
michael@0: (
michael@0:   nssCKFWHash *hash
michael@0: )
michael@0: {
michael@0:   CK_ULONG count;
michael@0: 
michael@0:   if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
michael@0:     return (CK_ULONG)0;
michael@0:   }
michael@0: 
michael@0:   count = hash->count;
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0: 
michael@0:   return count;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Exists
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT CK_BBOOL
michael@0: nssCKFWHash_Exists
michael@0: (
michael@0:   nssCKFWHash *hash,
michael@0:   const void *it
michael@0: )
michael@0: {
michael@0:   void *value;
michael@0: 
michael@0:   if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
michael@0:     return CK_FALSE;
michael@0:   }
michael@0: 
michael@0:   value = PL_HashTableLookup(hash->plHashTable, it);
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0: 
michael@0:   if (!value) {
michael@0:     return CK_FALSE;
michael@0:   } else {
michael@0:     return CK_TRUE;
michael@0:   }
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Lookup
michael@0:  *
michael@0:  */
michael@0: NSS_IMPLEMENT void *
michael@0: nssCKFWHash_Lookup
michael@0: (
michael@0:   nssCKFWHash *hash,
michael@0:   const void *it
michael@0: )
michael@0: {
michael@0:   void *rv;
michael@0: 
michael@0:   if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
michael@0:     return (void *)NULL;
michael@0:   }
michael@0: 
michael@0:   rv = PL_HashTableLookup(hash->plHashTable, it);
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0: 
michael@0:   return rv;
michael@0: }
michael@0: 
michael@0: struct arg_str {
michael@0:   nssCKFWHashIterator fcn;
michael@0:   void *closure;
michael@0: };
michael@0: 
michael@0: static PRIntn
michael@0: nss_ckfwhash_enumerator
michael@0: (
michael@0:   PLHashEntry *he,
michael@0:   PRIntn index,
michael@0:   void *arg
michael@0: )
michael@0: {
michael@0:   struct arg_str *as = (struct arg_str *)arg;
michael@0:   as->fcn(he->key, he->value, as->closure);
michael@0:   return HT_ENUMERATE_NEXT;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * nssCKFWHash_Iterate
michael@0:  *
michael@0:  * NOTE that the iteration function will be called with the hashtable locked.
michael@0:  */
michael@0: NSS_IMPLEMENT void
michael@0: nssCKFWHash_Iterate
michael@0: (
michael@0:   nssCKFWHash *hash,
michael@0:   nssCKFWHashIterator fcn,
michael@0:   void *closure
michael@0: )
michael@0: {
michael@0:   struct arg_str as;
michael@0:   as.fcn = fcn;
michael@0:   as.closure = closure;
michael@0: 
michael@0:   if( CKR_OK != nssCKFWMutex_Lock(hash->mutex) ) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   PL_HashTableEnumerateEntries(hash->plHashTable, nss_ckfwhash_enumerator, &as);
michael@0: 
michael@0:   (void)nssCKFWMutex_Unlock(hash->mutex);
michael@0: 
michael@0:   return;
michael@0: }