nsMemory.h
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- /* -*- Mode: C++; tab-width: 4; 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 ***** */
- #ifndef nsMemory_h__
- #define nsMemory_h__
- #include "nsXPCOM.h"
- #include "nsIMemory.h"
- #define NS_MEMORY_CONTRACTID "@mozilla.org/xpcom/memory-service;1"
- #define NS_MEMORY_CLASSNAME "Global Memory Service"
- #define NS_MEMORY_CID
- { /* 30a04e40-38e7-11d4-8cf5-0060b0fc14a3 */
- 0x30a04e40,
- 0x38e7,
- 0x11d4,
- {0x8c, 0xf5, 0x00, 0x60, 0xb0, 0xfc, 0x14, 0xa3}
- }
- /**
- * Static helper routines to manage memory. These routines allow easy access
- * to xpcom's built-in (global) nsIMemory implementation, without needing
- * to go through the service manager to get it. However this requires clients
- * to link with the xpcom DLL.
- *
- * This class is not threadsafe and is intented for use only on the main
- * thread.
- */
- class nsMemory
- {
- public:
- static NS_HIDDEN_(void*) Alloc(size_t size)
- { return NS_Alloc(size); }
- static NS_HIDDEN_(void*) Realloc(void* ptr, PRSize size)
- { return NS_Realloc(ptr, size); }
- static NS_HIDDEN_(void) Free(void* ptr)
- { NS_Free(ptr); }
- static NS_COM_GLUE nsresult HeapMinimize(PRBool aImmediate);
- static NS_COM_GLUE void* Clone(const void* ptr, PRSize size);
- static NS_COM_GLUE nsIMemory* GetGlobalMemoryService(); // AddRefs
- };
- /**
- * Macro to free all elements of an XPCOM array of a given size using
- * freeFunc, then frees the array itself using nsMemory::Free().
- *
- * Note that this macro (and its wrappers) can be used to deallocate a
- * partially- or completely-built array while unwinding an error
- * condition inside the XPCOM routine that was going to return the
- * array. For this to work on a partially-built array, your code
- * needs to be building the array from index 0 upwards, and simply
- * pass the number of elements that have already been built (and thus
- * need to be freed) as |size|.
- *
- * Thanks to <alecf@netscape.com> for suggesting this form, which
- * allows the macro to be used with NS_RELEASE / NS_RELEASE_IF in
- * addition to nsMemory::Free.
- *
- * @param size Number of elements in the array. If not a constant, this
- * should be a PRInt32. Note that this means this macro
- * will not work if size >= 2^31.
- * @param array The array to be freed.
- * @param freeFunc The function or macro to be used to free it.
- * For arrays of nsISupports (or any class derived
- * from it), NS_IF_RELEASE (or NS_RELEASE) should be
- * passed as freeFunc. For most (all?) other pointer
- * types (including XPCOM strings and wstrings),
- * nsMemory::Free should be used, since the
- * shared-allocator (nsMemory) is what will have been
- * used to allocate the memory.
- */
- #define NS_FREE_XPCOM_POINTER_ARRAY(size, array, freeFunc)
- PR_BEGIN_MACRO
- PRInt32 iter_ = PRInt32(size);
- while (--iter_ >= 0)
- freeFunc((array)[iter_]);
- NS_Free((array));
- PR_END_MACRO
- // convenience macros for commonly used calls. mmmmm. syntactic sugar.
- /**
- * Macro to free arrays of non-refcounted objects allocated by the
- * shared allocator (nsMemory) such as strings and wstrings. A
- * convenience wrapper around NS_FREE_XPCOM_POINTER_ARRAY.
- *
- * @param size Number of elements in the array. If not a constant, this
- * should be a PRInt32. Note that this means this macro
- * will not work if size >= 2^31.
- * @param array The array to be freed.
- */
- #define NS_FREE_XPCOM_ALLOCATED_POINTER_ARRAY(size, array)
- NS_FREE_XPCOM_POINTER_ARRAY((size), (array), NS_Free)
- /**
- * Macro to free an array of pointers to nsISupports (or classes
- * derived from it). A convenience wrapper around
- * NS_FREE_XPCOM_POINTER_ARRAY.
- *
- * Note that if you know that none of your nsISupports pointers are
- * going to be 0, you can gain a bit of speed by calling
- * NS_FREE_XPCOM_POINTER_ARRAY directly and using NS_RELEASE as your
- * free function.
- *
- * @param size Number of elements in the array. If not a constant, this
- * should be a PRInt32. Note that this means this macro
- * will not work if size >= 2^31.
- * @param array The array to be freed.
- */
- #define NS_FREE_XPCOM_ISUPPORTS_POINTER_ARRAY(size, array)
- NS_FREE_XPCOM_POINTER_ARRAY((size), (array), NS_IF_RELEASE)
- /**
- * Helpful array length function for calculating the length of a
- * statically declared array.
- */
- #define NS_ARRAY_LENGTH(array_)
- (sizeof(array_)/sizeof(array_[0]))
- #endif // nsMemory_h__