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-rw-r--r--src/libs/xpcom18a4/xpcom/io/nsSegmentedBuffer.cpp207
1 files changed, 207 insertions, 0 deletions
diff --git a/src/libs/xpcom18a4/xpcom/io/nsSegmentedBuffer.cpp b/src/libs/xpcom18a4/xpcom/io/nsSegmentedBuffer.cpp
new file mode 100644
index 00000000..f6a1c15d
--- /dev/null
+++ b/src/libs/xpcom18a4/xpcom/io/nsSegmentedBuffer.cpp
@@ -0,0 +1,207 @@
+/* -*- Mode: C++; tab-width: 2; 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):
+ *
+ * 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 ***** */
+
+#include "nsSegmentedBuffer.h"
+#include "nsCRT.h"
+
+nsresult
+nsSegmentedBuffer::Init(PRUint32 segmentSize, PRUint32 maxSize,
+ nsIMemory* allocator)
+{
+ if (mSegmentArrayCount != 0)
+ return NS_ERROR_FAILURE; // initialized more than once
+ mSegmentSize = segmentSize;
+ mMaxSize = maxSize;
+ mSegAllocator = allocator;
+ if (mSegAllocator == nsnull) {
+ mSegAllocator = nsMemory::GetGlobalMemoryService();
+ }
+ else {
+ NS_ADDREF(mSegAllocator);
+ }
+#if 0 // testing...
+ mSegmentArrayCount = 2;
+#else
+ mSegmentArrayCount = NS_SEGMENTARRAY_INITIAL_COUNT;
+#endif
+ return NS_OK;
+}
+
+char*
+nsSegmentedBuffer::AppendNewSegment()
+{
+ if (GetSize() >= mMaxSize)
+ return nsnull;
+
+ if (mSegmentArray == nsnull) {
+ PRUint32 bytes = mSegmentArrayCount * sizeof(char*);
+ mSegmentArray = (char**)nsMemory::Alloc(bytes);
+ if (mSegmentArray == nsnull)
+ return nsnull;
+ memset(mSegmentArray, 0, bytes);
+ }
+
+ if (IsFull()) {
+ PRUint32 newArraySize = mSegmentArrayCount * 2;
+ PRUint32 bytes = newArraySize * sizeof(char*);
+ char** newSegArray = (char**)nsMemory::Realloc(mSegmentArray, bytes);
+ if (newSegArray == nsnull)
+ return nsnull;
+ mSegmentArray = newSegArray;
+ // copy wrapped content to new extension
+ if (mFirstSegmentIndex > mLastSegmentIndex) {
+ // deal with wrap around case
+ memcpy(&mSegmentArray[mSegmentArrayCount],
+ mSegmentArray,
+ mLastSegmentIndex * sizeof(char*));
+ memset(mSegmentArray, 0, mLastSegmentIndex * sizeof(char*));
+ mLastSegmentIndex += mSegmentArrayCount;
+ memset(&mSegmentArray[mLastSegmentIndex], 0,
+ (newArraySize - mLastSegmentIndex) * sizeof(char*));
+ }
+ else {
+ memset(&mSegmentArray[mLastSegmentIndex], 0,
+ (newArraySize - mLastSegmentIndex) * sizeof(char*));
+ }
+ mSegmentArrayCount = newArraySize;
+ }
+
+ char* seg = (char*)mSegAllocator->Alloc(mSegmentSize);
+ if (seg == nsnull) {
+ return nsnull;
+ }
+ mSegmentArray[mLastSegmentIndex] = seg;
+ mLastSegmentIndex = ModSegArraySize(mLastSegmentIndex + 1);
+ return seg;
+}
+
+PRBool
+nsSegmentedBuffer::DeleteFirstSegment()
+{
+ NS_ASSERTION(mSegmentArray[mFirstSegmentIndex] != nsnull, "deleting bad segment");
+ (void)mSegAllocator->Free(mSegmentArray[mFirstSegmentIndex]);
+ mSegmentArray[mFirstSegmentIndex] = nsnull;
+ PRInt32 last = ModSegArraySize(mLastSegmentIndex - 1);
+ if (mFirstSegmentIndex == last) {
+ mLastSegmentIndex = last;
+ return PR_TRUE;
+ }
+ else {
+ mFirstSegmentIndex = ModSegArraySize(mFirstSegmentIndex + 1);
+ return PR_FALSE;
+ }
+}
+
+PRBool
+nsSegmentedBuffer::DeleteLastSegment()
+{
+ PRInt32 last = ModSegArraySize(mLastSegmentIndex - 1);
+ NS_ASSERTION(mSegmentArray[last] != nsnull, "deleting bad segment");
+ (void)mSegAllocator->Free(mSegmentArray[last]);
+ mSegmentArray[last] = nsnull;
+ mLastSegmentIndex = last;
+ return (PRBool)(mLastSegmentIndex == mFirstSegmentIndex);
+}
+
+PRBool
+nsSegmentedBuffer::ReallocLastSegment(size_t newSize)
+{
+ PRInt32 last = ModSegArraySize(mLastSegmentIndex - 1);
+ NS_ASSERTION(mSegmentArray[last] != nsnull, "realloc'ing bad segment");
+ char *newSegment =
+ (char*)mSegAllocator->Realloc(mSegmentArray[last], newSize);
+ if (newSegment) {
+ mSegmentArray[last] = newSegment;
+ return PR_TRUE;
+ } else {
+ return PR_FALSE;
+ }
+}
+
+void
+nsSegmentedBuffer::Empty()
+{
+ if (mSegmentArray) {
+ for (PRUint32 i = 0; i < mSegmentArrayCount; i++) {
+ if (mSegmentArray[i])
+ mSegAllocator->Free(mSegmentArray[i]);
+ }
+ nsMemory::Free(mSegmentArray);
+ mSegmentArray = nsnull;
+ }
+ mSegmentArrayCount = NS_SEGMENTARRAY_INITIAL_COUNT;
+ mFirstSegmentIndex = mLastSegmentIndex = 0;
+}
+
+#ifdef DEBUG
+NS_COM void
+TestSegmentedBuffer()
+{
+ nsSegmentedBuffer* buf = new nsSegmentedBuffer();
+ NS_ASSERTION(buf, "out of memory");
+ buf->Init(4, 16);
+ char* seg;
+ PRBool empty;
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(!empty, "DeleteFirstSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(!empty, "DeleteFirstSegment failed");
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ seg = buf->AppendNewSegment();
+ NS_ASSERTION(seg, "AppendNewSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(!empty, "DeleteFirstSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(!empty, "DeleteFirstSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(!empty, "DeleteFirstSegment failed");
+ empty = buf->DeleteFirstSegment();
+ NS_ASSERTION(empty, "DeleteFirstSegment failed");
+ delete buf;
+}
+#endif
+
+////////////////////////////////////////////////////////////////////////////////