Memory.h

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//
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#pragma once

#include <cstddef>
#include <cstring>

#include <OnixS/CboeCFE/Trading/BOE/Integral.h>

namespace OnixS
{
    namespace CboeCFE
    {
        namespace Trading
        {
            namespace BOE
            {
                /// Alias for Byte. 
                typedef UInt8 Byte;

                /// Alias for Word. 
                typedef UInt16 Word;

                /// Alias for Double Word. 
                typedef UInt32 DWord;

                /// Alias for Quad Word. 
                typedef UInt64 QWord;

                /// Casts data of source type to the data 
                /// of target type using C casting rules. 
                template
                    <
                    typename Target,
                    typename Source
                    >
                    inline Target c_cast(Source src)
                {
                    return (Target)src;
                }

                /// Makes pointer as opaque one. 
                template
                    <
                    typename Type
                    >
                    inline
                    void*
                    toOpaquePtr(Type* ptr)
                {
                    return static_cast<void*>(ptr);
                }

                /// Makes pointer as opaque one. 
                template
                    <
                    typename Type
                    >
                    inline
                    const void*
                    toOpaquePtr(
                        const Type* ptr)
                {
                    return static_cast<const void*>(ptr);
                }

                /// Reinterprets pointer to one 
                /// referencing to byte block. 
                template
                    <
                    typename Type
                    >
                    inline
                    Byte*
                    toByteBlock(
                        Type* ptr)
                {
                    return
                        static_cast
                        <Byte*>
                        (toOpaquePtr(ptr));
                }

                /// Reinterprets pointer to one 
                /// referencing to byte block. 
                template
                    <
                    typename Type
                    >
                    inline
                    const Byte*
                    toByteBlock(
                        const Type* ptr)
                {
                    return
                        static_cast
                        <const Byte*>
                        (toOpaquePtr(ptr));
                }

                /// Advances given pointer to a given offset (distance) in bytes. 
                template
                    <
                    typename Type
                    >
                    inline
                    Type*
                    advanceByBytes(
                        Type* pointer,
                        ptrdiff_t distance)
                {
                    return
                        reinterpret_cast<Type*>
                        (
                            toByteBlock(pointer) + distance
                            );
                }

                /// Returns pointer which is lower than 
                /// given one to a given number of bytes. 
                template
                    <
                    typename Type
                    >
                    inline
                    Type*
                    advanceBackByBytes(
                        Type* pointer,
                        ptrdiff_t distance)
                {
                    return
                        reinterpret_cast<Type*>
                        (
                            toByteBlock(pointer) - distance
                            );
                }

                /// Returns distance in bytes between two pointers. 
                template
                    <
                    typename Left,
                    typename Right
                    >
                    inline
                    ptrdiff_t
                    byteDistance(
                        Left* left,
                        Right* right)
                {
                    return (
                        toByteBlock(left) -
                        toByteBlock(right)
                        );
                }

                template
                    <
                    class FieldValue
                    >
                inline
                FieldValue
                unalignedCopy(const void* p) ONIXS_BATS_BOE_NOTHROW
                {
                    FieldValue value;
                    memcpy(&value, p, sizeof(FieldValue));
                    return value;
                }
            }
        }
    }
}