gecko-dev/xpcom/base/nsIAllocator.h

115 lines
3.6 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape 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/NPL/
*
* 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 Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*/
#ifndef nsIAllocator_h___
#define nsIAllocator_h___
#include "nsISupports.h"
/**
* Unlike IMalloc, this interface returns nsresults and doesn't
* implement the problematic GetSize and DidAlloc routines.
*/
#define NS_IALLOCATOR_IID \
{ /* 56def700-b1b9-11d2-8177-006008119d7a */ \
0x56def700, \
0xb1b9, \
0x11d2, \
{0x81, 0x77, 0x00, 0x60, 0x08, 0x11, 0x9d, 0x7a} \
}
#define NS_ALLOCATOR_PROGID "component://netscape/allocator"
#define NS_ALLOCATOR_CLASSNAME "Allocator"
class nsIAllocator : public nsISupports {
public:
static const nsIID& GetIID() { static nsIID iid = NS_IALLOCATOR_IID; return iid; }
/**
* Allocates a block of memory of a particular size.
*
* @param size - the size of the block to allocate
* @result the block of memory
*/
NS_IMETHOD_(void*) Alloc(PRUint32 size) = 0;
/**
* Reallocates a block of memory to a new size.
*
* @param ptr - the block of memory to reallocate
* @param size - the new size
* @result the rellocated block of memory
*/
NS_IMETHOD_(void*) Realloc(void* ptr, PRUint32 size) = 0;
/**
* Frees a block of memory.
*
* @param ptr - the block of memory to free
* @param size - the size of the block to be freed. If -1 (the default),
* the implementation must be able to determine the block size by
* examining the block pointer.
*/
NS_IMETHOD Free(void* ptr) = 0;
/**
* Attempts to shrink the heap.
*/
NS_IMETHOD HeapMinimize(void) = 0;
};
// To get the global memory manager service:
#define NS_ALLOCATOR_CID \
{ /* aafe6770-b1bb-11d2-8177-006008119d7a */ \
0xaafe6770, \
0xb1bb, \
0x11d2, \
{0x81, 0x77, 0x00, 0x60, 0x08, 0x11, 0x9d, 0x7a} \
}
/*
* Public shortcuts to the shared allocator's methods
*/
class nsAllocator
{
public:
static NS_EXPORT void* Alloc(PRUint32 size);
static NS_EXPORT void* Realloc(void* ptr, PRUint32 size);
static NS_EXPORT void Free(void* ptr);
static NS_EXPORT void HeapMinimize();
static NS_EXPORT void* Clone(const void* ptr, PRUint32 size);
static NS_EXPORT nsIAllocator* GetGlobalAllocator();
static NS_EXPORT void Shutdown();
private:
nsAllocator(); // not implemented
static PRBool EnsureAllocator() {return mAllocator || FetchAllocator();}
static PRBool FetchAllocator();
static nsIAllocator* mAllocator;
};
////////////////////////////////////////////////////////////////////////////////
#endif /* nsIAllocator_h___ */