gecko/layout/base/nsPresArena.h

113 lines
4.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=2 sw=2 et tw=78:
* ***** 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):
* Steve Clark <buster@netscape.com>
* HÃ¥kan Waara <hwaara@chello.se>
* Dan Rosen <dr@netscape.com>
* Daniel Glazman <glazman@netscape.com>
* Mats Palmgren <mats.palmgren@bredband.net>
*
* 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 *****
*/
#ifndef nsPresArena_h___
#define nsPresArena_h___
#include "nscore.h"
#include "nsQueryFrame.h"
#include "mozilla/StandardInteger.h"
// Uncomment this to disable arenas, instead forwarding to
// malloc for every allocation.
//#define DEBUG_TRACEMALLOC_PRESARENA 1
// The debugging version of nsPresArena does not free all the memory it
// allocated when the arena itself is destroyed.
#ifdef DEBUG_TRACEMALLOC_PRESARENA
#define PRESARENA_MUST_FREE_DURING_DESTROY true
#else
#define PRESARENA_MUST_FREE_DURING_DESTROY false
#endif
class nsPresArena {
public:
nsPresArena();
~nsPresArena();
// Pool allocation with recycler lists indexed by object size, aSize.
NS_HIDDEN_(void*) AllocateBySize(size_t aSize);
NS_HIDDEN_(void) FreeBySize(size_t aSize, void* aPtr);
// Pool allocation with recycler lists indexed by frame-type ID.
// Every aID must always be used with the same object size, aSize.
NS_HIDDEN_(void*) AllocateByFrameID(nsQueryFrame::FrameIID aID, size_t aSize);
NS_HIDDEN_(void) FreeByFrameID(nsQueryFrame::FrameIID aID, void* aPtr);
enum ObjectID {
nsLineBox_id = nsQueryFrame::NON_FRAME_MARKER,
// The PresArena implementation uses this bit to distinguish objects
// allocated by size from objects allocated by type ID (that is, frames
// using AllocateByFrameID and other objects using AllocateByObjectID).
// It should not collide with any Object ID (above) or frame ID (in
// nsQueryFrame.h). It is not 0x80000000 to avoid the question of
// whether enumeration constants are signed.
NON_OBJECT_MARKER = 0x40000000
};
// Pool allocation with recycler lists indexed by object-type ID (see above).
// Every aID must always be used with the same object size, aSize.
NS_HIDDEN_(void*) AllocateByObjectID(ObjectID aID, size_t aSize);
NS_HIDDEN_(void) FreeByObjectID(ObjectID aID, void* aPtr);
size_t SizeOfExcludingThis(nsMallocSizeOfFun aMallocSizeOf) const;
/**
* Get the poison value that can be used to fill a memory space with
* an address that leads to a safe crash when dereferenced.
*
* The caller is responsible for ensuring that a pres shell has been
* initialized before calling this.
*/
static uintptr_t GetPoisonValue();
private:
struct State;
State* mState;
};
#endif