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/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * 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 Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Chris Waterson <waterson@netscape.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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#include "nsClusterKeySet.h"

PLHashAllocOps nsClusterKeySet::gAllocOps = {
    AllocTable, FreeTable, AllocEntry, FreeEntry };


nsClusterKeySet::nsClusterKeySet()
    : mTable(nsnull)
{
    mHead.mPrev = mHead.mNext = &mHead;

    static const size_t kBucketSizes[] = { sizeof(Entry) };
    static const PRInt32 kNumBuckets = sizeof(kBucketSizes) / sizeof(size_t);
    static const PRInt32 kInitialEntries = 8;

    // Per news://news.mozilla.org/39BEC105.5090206%40netscape.com
    static const PRInt32 kInitialPoolSize = 256;

    mPool.Init("nsClusterKeySet", kBucketSizes, kNumBuckets, kInitialPoolSize);

    mTable = PL_NewHashTable(kInitialEntries,
                             nsClusterKey::HashClusterKey,
                             nsClusterKey::CompareClusterKeys,
                             PL_CompareValues, &gAllocOps, &mPool);

    MOZ_COUNT_CTOR(nsClusterKeySet);
}


nsClusterKeySet::~nsClusterKeySet()
{
    PL_HashTableDestroy(mTable);
    MOZ_COUNT_DTOR(nsClusterKeySet);
}

PRBool
nsClusterKeySet::Contains(const nsClusterKey& aKey)
{
    return nsnull != PL_HashTableLookup(mTable, &aKey);
}

nsresult
nsClusterKeySet::Add(const nsClusterKey& aKey)
{
    PLHashNumber hash = aKey.Hash();
    PLHashEntry** hep = PL_HashTableRawLookup(mTable, hash, &aKey);

    if (hep && *hep)
        return NS_OK; // already had it.

    PLHashEntry* he = PL_HashTableRawAdd(mTable, hep, hash, &aKey, nsnull);
    if (! he)
        return NS_ERROR_OUT_OF_MEMORY;

    Entry* entry = NS_REINTERPRET_CAST(Entry*, he);

    // XXX yes, I am evil. Fixup the key in the hashentry to point to
    // the value it contains, rather than the one on the stack.
    entry->mHashEntry.key = &entry->mKey;

    // thread
    mHead.mPrev->mNext = entry;
    entry->mPrev = mHead.mPrev;
    entry->mNext = &mHead;
    mHead.mPrev = entry;
    
    return NS_OK;
}