1 files changed, 153 insertions, 0 deletions
diff --git a/src/libs/xpcom18a4/xpcom/ds/nsFixedSizeAllocator.cpp b/src/libs/xpcom18a4/xpcom/ds/nsFixedSizeAllocator.cpp
new file mode 100644
index 00000000..1b6232f9
--- /dev/null
+++ b/src/libs/xpcom18a4/xpcom/ds/nsFixedSizeAllocator.cpp
@@ -0,0 +1,153 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ***** 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.org 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
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+
+  Implementation for nsFixedSizeAllocator
+
+*/
+
+#include "nsCRT.h"
+#include "nsFixedSizeAllocator.h"
+
+nsFixedSizeAllocator::Bucket *
+nsFixedSizeAllocator::AddBucket(size_t aSize)
+{
+    void* p;
+    PL_ARENA_ALLOCATE(p, &mPool, sizeof(Bucket));
+    if (! p)
+        return nsnull;
+
+    Bucket* bucket = NS_STATIC_CAST(Bucket*, p);
+    bucket->mSize  = aSize;
+    bucket->mFirst = nsnull;
+    bucket->mNext  = mBuckets;
+
+    mBuckets = bucket;
+    return bucket;
+}
+
+nsresult
+nsFixedSizeAllocator::Init(const char* aName,
+                           const size_t* aBucketSizes,
+                           PRInt32 aNumBuckets,
+                           PRInt32 aInitialSize,
+                           PRInt32 aAlign)
+{
+    NS_PRECONDITION(aNumBuckets > 0, "no buckets");
+    if (aNumBuckets <= 0)
+        return NS_ERROR_INVALID_ARG;
+
+    // Blow away the old pool if we're being re-initialized.
+    if (mBuckets)
+        PL_FinishArenaPool(&mPool);
+
+    PRInt32 bucketspace = aNumBuckets * sizeof(Bucket);
+    PL_InitArenaPool(&mPool, aName, bucketspace + aInitialSize, aAlign);
+
+    mBuckets = nsnull;
+    for (PRInt32 i = 0; i < aNumBuckets; ++i)
+        AddBucket(aBucketSizes[i]);
+
+    return NS_OK;
+}
+
+nsFixedSizeAllocator::Bucket *
+nsFixedSizeAllocator::FindBucket(size_t aSize)
+{
+    Bucket** link = &mBuckets;
+    Bucket* bucket;
+
+    while ((bucket = *link) != nsnull) {
+        if (aSize == bucket->mSize) {
+            // Promote to the head of the list, under the assumption
+            // that we'll allocate same-sized object contemporaneously.
+            *link = bucket->mNext;
+            bucket->mNext = mBuckets;
+            mBuckets = bucket;
+            return bucket;
+        }
+
+        link = &bucket->mNext;
+    }
+    return nsnull;
+}
+
+void*
+nsFixedSizeAllocator::Alloc(size_t aSize)
+{
+    Bucket* bucket = FindBucket(aSize);
+    if (! bucket) {
+        // Oops, we don't carry that size. Let's fix that.
+        bucket = AddBucket(aSize);
+        if (! bucket)
+            return nsnull;
+    }
+
+    void* next;
+    if (bucket->mFirst) {
+        next = bucket->mFirst;
+        bucket->mFirst = bucket->mFirst->mNext;
+    }
+    else {
+        PL_ARENA_ALLOCATE(next, &mPool, aSize);
+        if (!next)
+            return nsnull;
+    }
+
+#ifdef DEBUG
+    memset(next, 0xc8, aSize);
+#endif
+
+    return next;
+}
+
+void
+nsFixedSizeAllocator::Free(void* aPtr, size_t aSize)
+{
+    FreeEntry* entry = NS_REINTERPRET_CAST(FreeEntry*, aPtr);
+    Bucket* bucket = FindBucket(aSize);
+
+#ifdef DEBUG
+    NS_ASSERTION(bucket && bucket->mSize == aSize, "ack! corruption! bucket->mSize != aSize!");
+    memset(aPtr, 0xd8, bucket->mSize);
+#endif
+
+    entry->mNext = bucket->mFirst;
+    bucket->mFirst = entry;
+}