fixed_mem_pool.h File Reference

Definition of a fixed-size memory pool template for structs/classes. More...

#include <new>
#include <assert.h>
#include <stddef.h>
#include "_nvwa.h"
#include "c++11.h"
#include "class_level_lock.h"
#include "mem_pool_base.h"
#include "static_assert.h"

Include dependency graph for fixed_mem_pool.h:

Go to the source code of this file.

Classes
class	nvwa::fixed_mem_pool< _Tp >
	Class template to manipulate a fixed-size memory pool. More...
struct	nvwa::fixed_mem_pool< _Tp >::alignment
	Specializable struct to define the alignment of an object in the fixed_mem_pool. More...
struct	nvwa::fixed_mem_pool< _Tp >::block_size
	Struct to calculate the block size based on the (specializable) alignment value. More...

Namespaces
	nvwa
	Namespace of the nvwa project.

Macros
#define	MEM_POOL_ALIGNMENT   sizeof(void*)
	Defines the alignment of memory blocks.
#define	DECLARE_FIXED_MEM_POOL(_Cls)
	Declares the normal (throwing) allocation and deallocation functions. More...
#define	DECLARE_FIXED_MEM_POOL__NOTHROW(_Cls)
	Declares the nothrow allocation and deallocation functions. More...
#define	DECLARE_FIXED_MEM_POOL__THROW_NOCHECK(_Cls)
	Declares the throwing, non-checking allocation and deallocation functions. More...

Detailed Description

Definition of a fixed-size memory pool template for structs/classes.

This is a easy-to-use class template for pre-allocated memory pools. The client side needs to do the following things:

• Use one of the macros
  • DECLARE_FIXED_MEM_POOL,
  • DECLARE_FIXED_MEM_POOL__NOTHROW, or
  • DECLARE_FIXED_MEM_POOL__THROW_NOCHECK
  at the end of the class (say, class _Cls) definitions.
• Optionally, specialize fixed_mem_pool::alignment to change the alignment value for this specific type.
• Optionally, specialize fixed_mem_pool::bad_alloc_handler to change the behaviour when all memory blocks are allocated.
• Call fixed_mem_pool<_Cls>::initialize at the beginning of the program.
• Optionally, call fixed_mem_pool<_Cls>::deinitialize at exit of the program to check for memory leaks.
• Optionally, call fixed_mem_pool<_Cls>::get_alloc_count to check memory usage when the program is running.

Date

2014-11-29

Macro Definition Documentation

DECLARE_FIXED_MEM_POOL

#define DECLARE_FIXED_MEM_POOL

(

_Cls

)

Value:

public: \
    static void* operator new(size_t size) \
    { \
        assert(size == sizeof(_Cls)); \
        if (void* ptr = NVWA::fixed_mem_pool<_Cls>::allocate()) \
            return ptr; \
        else \
            throw std::bad_alloc(); \
    } \
    static void  operator delete(void* ptr) \
    { \
        if (ptr != _NULLPTR) \
            NVWA::fixed_mem_pool<_Cls>::deallocate(ptr); \
    }

Declares the normal (throwing) allocation and deallocation functions.

Parameters

_Cls	class to use the fixed_mem_pool

See also

DECLARE_FIXED_MEM_POOL__THROW_NOCHECK, which, too, defines an operator new that will never return null, but requires more discipline on the programmer's side.

DECLARE_FIXED_MEM_POOL__NOTHROW

#define DECLARE_FIXED_MEM_POOL__NOTHROW

(

_Cls

)

Value:

public: \
    static void* operator new(size_t size) _NOEXCEPT \
    { \
        assert(size == sizeof(_Cls)); \
        return NVWA::fixed_mem_pool<_Cls>::allocate(); \
    } \
    static void  operator delete(void* ptr) \
    { \
        if (ptr != _NULLPTR) \
            NVWA::fixed_mem_pool<_Cls>::deallocate(ptr); \
    }

Declares the nothrow allocation and deallocation functions.

Parameters

_Cls	class to use the fixed_mem_pool

DECLARE_FIXED_MEM_POOL__THROW_NOCHECK

#define DECLARE_FIXED_MEM_POOL__THROW_NOCHECK

(

_Cls

)

Value:

public: \
    static void* operator new(size_t size) \
    { \
        assert(size == sizeof(_Cls)); \
        return NVWA::fixed_mem_pool<_Cls>::allocate(); \
    } \
    static void  operator delete(void* ptr) \
    { \
        if (ptr != _NULLPTR) \
            NVWA::fixed_mem_pool<_Cls>::deallocate(ptr); \
    }

Declares the throwing, non-checking allocation and deallocation functions.

N.B. Using this macro requires users to explicitly specialize fixed_mem_pool::bad_alloc_handler so that it shall never return false (it may throw exceptions, say, std::bad_alloc, or simply abort). Otherwise a segmentation fault might occur (instead of returning a null pointer).

Parameters

_Cls	class to use the fixed_mem_pool