| /**************************************************************************** |
| ** |
| ** Copyright (C) 2001-2004 Roberto Raggi |
| ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). |
| ** All rights reserved. |
| ** Contact: Nokia Corporation (qt-info@nokia.com) |
| ** |
| ** This file is part of the qt3to4 porting application of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL$ |
| ** GNU Lesser General Public License Usage |
| ** 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 1.1, 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. |
| ** |
| ** Other Usage |
| ** Alternatively, this file may be used in accordance with the terms and |
| ** conditions contained in a signed written agreement between you and Nokia. |
| ** |
| ** |
| ** |
| ** |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #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 |