summaryrefslogtreecommitdiffstats
path: root/tools/porting/src/smallobject.h
diff options
context:
space:
mode:
authorLars Knoll <lars.knoll@nokia.com>2009-03-23 09:18:55 (GMT)
committerSimon Hausmann <simon.hausmann@nokia.com>2009-03-23 09:18:55 (GMT)
commite5fcad302d86d316390c6b0f62759a067313e8a9 (patch)
treec2afbf6f1066b6ce261f14341cf6d310e5595bc1 /tools/porting/src/smallobject.h
downloadQt-e5fcad302d86d316390c6b0f62759a067313e8a9.zip
Qt-e5fcad302d86d316390c6b0f62759a067313e8a9.tar.gz
Qt-e5fcad302d86d316390c6b0f62759a067313e8a9.tar.bz2
Long live Qt 4.5!
Diffstat (limited to 'tools/porting/src/smallobject.h')
-rw-r--r--tools/porting/src/smallobject.h182
1 files changed, 182 insertions, 0 deletions
diff --git a/tools/porting/src/smallobject.h b/tools/porting/src/smallobject.h
new file mode 100644
index 0000000..f086b70
--- /dev/null
+++ b/tools/porting/src/smallobject.h
@@ -0,0 +1,182 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+** Copyright (C) 2001-2004 Roberto Raggi
+**
+** This file is part of the qt3to4 porting application of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef SMALLOBJECT_H
+#define SMALLOBJECT_H
+
+#include <QList>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+QT_BEGIN_NAMESPACE
+
+struct block_t
+{
+ static int N;
+
+ block_t *chain;
+ char *data;
+ char *ptr;
+ char *end;
+
+ inline void init(int block_size = 256)
+ {
+ ++N;
+ chain = 0;
+ data = (char*) malloc(block_size);
+ ptr = data;
+ end = data + block_size;
+ }
+
+ inline void init0(int block_size)
+ {
+ init();
+ memset(data, '0', block_size);
+ }
+
+ inline void destroy()
+ {
+ --N;
+ if (chain) {
+ chain->destroy();
+ free(chain);
+ }
+
+ free(data);
+ }
+
+ inline void *allocate(size_t size, block_t **right_most)
+ {
+ const unsigned int block_size = 1 << 16;
+ if (end < ptr + size) {
+ assert( size < block_size );
+
+ if (!chain) {
+ chain = (block_t*) malloc(sizeof(block_t));
+ Q_ASSERT(chain);
+ chain->init(block_size);
+ }
+
+ return chain->allocate(size, right_most);
+ }
+
+ char *r = ptr;
+ ptr += size;
+
+ if (right_most)
+ *right_most = this;
+
+ return r;
+ }
+
+};
+
+// a stupid memory pool
+struct pool
+{
+ block_t blk;
+ block_t *right_most;
+
+ inline pool() { blk.init(); right_most = &blk; }
+ inline ~pool() { blk.destroy(); }
+
+ inline void *allocate(size_t size)
+ {
+ void *ptr = right_most->allocate(size, &right_most);
+ Q_ASSERT(ptr);
+ return ptr;
+
+ }
+ inline void *reallocate(void *old, size_t old_size, size_t size)
+ {
+ void *alloc = right_most->allocate(size, &right_most);
+ memcpy(alloc, old, old_size);
+ return alloc;
+ }
+private:
+ Q_DISABLE_COPY(pool)
+};
+
+/*
+ A memory pool that calls the destructor for each stored item when memory is
+ freed, at the expence storing one BaseType* per item.
+
+ Note that allocations for types that does not inherit BaseType
+ is not allowed and will result in a crash when the memory is freed.
+*/
+template <typename BaseType>
+class TypedPool
+{
+public:
+ inline TypedPool() { blk.init(); right_most = &blk; }
+ inline ~TypedPool()
+ {
+ foreach(BaseType *item, allocated)
+ item->~BaseType();
+ blk.destroy();
+ }
+
+ inline void *allocate(size_t size)
+ {
+ void *memory = right_most->allocate(size, &right_most);
+ allocated.append(reinterpret_cast<BaseType *>(memory));
+ Q_ASSERT(memory);
+ return memory;
+ }
+private:
+ Q_DISABLE_COPY(TypedPool)
+ block_t blk;
+ block_t *right_most;
+ QList<BaseType *> allocated;
+};
+
+struct SmallObject
+{
+ static void *operator new(size_t size);
+ static void operator delete(void *p);
+};
+
+QT_END_NAMESPACE
+
+#endif