/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=8 sts=2 et sw=2 tw=80: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #ifndef nsMemory_h__ #define nsMemory_h__ #include "nsXPCOM.h" class nsIMemory; #define NS_MEMORY_CONTRACTID "@mozilla.org/xpcom/memory-service;1" #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 aSize) { return NS_Alloc(aSize); } static NS_HIDDEN_(void*) Realloc(void* aPtr, size_t aSize) { return NS_Realloc(aPtr, aSize); } static NS_HIDDEN_(void) Free(void* aPtr) { NS_Free(aPtr); } static NS_COM_GLUE nsresult HeapMinimize(bool aImmediate); static NS_COM_GLUE void* Clone(const void* aPtr, size_t aSize); 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 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 int32_t. 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 \ int32_t iter_ = int32_t(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 int32_t. 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 int32_t. 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) /** * A macro, NS_ALIGNMENT_OF(t_) that determines the alignment * requirements of a type. */ namespace mozilla { template struct AlignmentTestStruct { char c; T t; }; } #define NS_ALIGNMENT_OF(t_) \ (sizeof(mozilla::AlignmentTestStruct) - sizeof(t_)) /** * An enumeration type used to represent a method of assignment. */ enum nsAssignmentType { NS_ASSIGNMENT_COPY, // copy by value NS_ASSIGNMENT_DEPEND, // copy by reference NS_ASSIGNMENT_ADOPT // copy by reference (take ownership of resource) }; #endif // nsMemory_h__