85 lines
2.1 KiB
C++
85 lines
2.1 KiB
C++
/*++
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Copyright (c) 1999-2000 Microsoft Corporation
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Module Name:
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membmgr2.hxx
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Abstract:
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This module contains the declarations for the MEM_ALLOCATOR
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class, which provides memory block of varialble size from
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a bigger block. All bigger blocks are then linked together
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thru a pointer at the end of each bigger block. This class
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is particularly suitable to user who needs a lot of small
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blocks but does not free any of them until there is no need
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to use the object anymore.
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Author:
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Daniel Chan (danielch) Oct 18, 1999
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--*/
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#if !defined( _MEM_ALLOCATOR_DEFN_ )
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#define _MEM_ALLOCATOR_DEFN_
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//
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// This class allocates a big buffer and then give a chunk of
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// it away each time Allocate is called. Each big buffer
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// is linked to the next one by having a pointer at the end
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// of the big buffer. The last buffer should have a NULL
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// pointer at the end of it.
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//
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class MEM_ALLOCATOR : public OBJECT {
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public:
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ULIB_EXPORT
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DECLARE_CONSTRUCTOR( MEM_ALLOCATOR );
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VIRTUAL
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ULIB_EXPORT
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~MEM_ALLOCATOR(
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);
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NONVIRTUAL
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ULIB_EXPORT
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BOOLEAN
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Initialize(
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IN ULONG64 MaximumMemoryToUse DEFAULT -1,
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IN ULONG IncrementalBlockSize DEFAULT 1024*1024
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);
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NONVIRTUAL
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ULIB_EXPORT
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PVOID
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Allocate(
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IN ULONG SizeInBytes
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);
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private:
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NONVIRTUAL
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VOID
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Construct(
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);
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NONVIRTUAL
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VOID
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Destroy(
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);
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PVOID _head_ptr; // points to the first big buffer
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PVOID _next_free_ptr; // points to the free space of the current big buffer
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ULONG _free_space_in_current_block; // amount of user space that's free in the
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// current big buffer
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ULONG _incremental_size; // how large is each big buffer
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ULONG64 _max_mem_use;
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ULONG64 _mem_use;
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};
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#endif
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