CComHeap Class
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This class implements IAtlMemMgr using the COM memory allocation functions.
Important
This class and its members cannot be used in applications that execute in the Windows Runtime.
Syntax
class CComHeap : public IAtlMemMgr
Members
Public Methods
| Name | Description |
|---|---|
| CComHeap::Allocate | Call this method to allocate a block of memory. |
| CComHeap::Free | Call this method to free a block of memory allocated by this memory manager. |
| CComHeap::GetSize | Call this method to get the allocated size of a memory block allocated by this memory manager. |
| CComHeap::Reallocate | Call this method to reallocate memory allocated by this memory manager. |
Remarks
CComHeap implements memory allocation functions using the COM allocation functions, including CoTaskMemAlloc, CoTaskMemFree, IMalloc::GetSize, and CoTaskMemRealloc. The maximum amount of memory that can be allocated is equal to INT_MAX (2147483647) bytes.
Example
See the example for IAtlMemMgr.
Inheritance Hierarchy
IAtlMemMgr
CComHeap
Requirements
Header: ATLComMem.h
CComHeap::Allocate
Call this method to allocate a block of memory.
virtual __declspec(allocator) void* Allocate(size_t nBytes) throw();
Parameters
nBytes
The requested number of bytes in the new memory block.
Return Value
Returns a pointer to the start of the newly allocated memory block.
Remarks
Call CComHeap::Free or CComHeap::Reallocate to free the memory allocated by this method.
Implemented using CoTaskMemAlloc.
CComHeap::Free
Call this method to free a block of memory allocated by this memory manager.
virtual void Free(void* p) throw();
Parameters
p
Pointer to memory previously allocated by this memory manager. NULL is a valid value and does nothing.
Remarks
Implemented using CoTaskMemFree.
CComHeap::GetSize
Call this method to get the allocated size of a memory block allocated by this memory manager.
virtual size_t GetSize(void* p) throw();
Parameters
p
Pointer to memory previously allocated by this memory manager.
Return Value
Returns the size of the allocated memory block in bytes.
Remarks
Implemented using IMalloc::GetSize.
CComHeap::Reallocate
Call this method to reallocate memory allocated by this memory manager.
virtual __declspec(allocator) void* Reallocate(void* p, size_t nBytes) throw();
Parameters
p
Pointer to memory previously allocated by this memory manager.
nBytes
The requested number of bytes in the new memory block.
Return Value
Returns a pointer to the start of the newly allocated memory block.
Remarks
Call CComHeap::Free to free the memory allocated by this method.
Implemented using CoTaskMemRealloc.
See Also
DynamicConsumer Sample
Class Overview
CWin32Heap Class
CLocalHeap Class
CGlobalHeap Class
CCRTHeap Class
IAtlMemMgr Class