scuffed-code/icu4c/source/layout/LESwaps.h

88 lines
1.9 KiB
C++

/*
*
* (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved
*
*/
#ifndef __LESWAPS_H
#define __LESWAPS_H
#include "LETypes.h"
/**
* \file
* \brief C++ API: Endian independent access to data for LayoutEngine
*/
U_NAMESPACE_BEGIN
/**
* A convenience macro which invokes the swapWord member function
* from a concise call.
*
* @stable ICU 2.8
*/
#define SWAPW(value) LESwaps::swapWord((const le_uint16 &) (value))
/**
* A convenience macro which invokes the swapLong member function
* from a concise call.
*
* @stable ICU 2.8
*/
#define SWAPL(value) LESwaps::swapLong((const le_uint32 &) (value))
/**
* This class is used to access data which stored in big endian order
* regardless of the conventions of the platform.
*
* All methods are static and inline in an attempt to induce the compiler
* to do most of the calculations at compile time.
*
* @stable ICU 2.8
*/
class U_LAYOUT_API LESwaps /* not : public UObject because all methods are static */ {
public:
/**
* This method does the byte swap required on little endian platforms
* to correctly access a (16-bit) word.
*
* @param value - the word to be byte swapped
*
* @return the byte swapped word
*
* @stable ICU 2.8
*/
static le_uint16 swapWord(const le_uint16 &value)
{
const le_uint8 *p = (const le_uint8 *) &value;
return ((p[0] << 8) + p[1]);
};
/**
* This method does the byte swapping required on little endian platforms
* to correctly access a (32-bit) long.
*
* @param value - the long to be byte swapped
*
* @return the byte swapped long
*
* @stable ICU 2.8
*/
static le_uint32 swapLong(const le_uint32 &value)
{
const le_uint8 *p = (const le_uint8 *) &value;
return ((p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]);
};
private:
LESwaps() {} // private - forbid instantiation
};
U_NAMESPACE_END
#endif