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/**
 * Author: Tiemo Jung
 * contact: tiemo dot jung at mni dot fh-giessen dot de
 * licencse: zlib Licencse
 * Copyright (c) 2012 Tiemo Jung
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 *  1. The origin of this software must not be misrepresented; you must not
 *  claim that you wrote the original software. If you use this software
 *  in a product, an acknowledgment in the product documentation would be
 *  appreciated but is not required.
 *
 *  2. Altered source versions must be plainly marked as such, and must not be
 *  misrepresented as being the original software.
 *
 *  3. This notice may not be removed or altered from any source
 *  distribution.
 */
 
A smal wrapper for base types to automaticly handle endianness conversations.

Defautl configuration is little endian, to enable big endian mode just define
BIG_ENDIAN before include the header file.

You can just replace any base type of a header def with the predefined endian 
maped type. 

Instead of writing:

struct header {
	// big endian
	int int_value;
	// little endian
	short short_value;
	// big endian
	char char_value;
	// little endian
	float float_value;
};

void load_header(void *data,heade *&header) {
	header = reinterpret_cast<header *>(data);
	header.int_value 	= to_big_endian(header.int_value);
	header.short_value 	= to_little_endian(header.short_value);
	header.char_value 	= to_big_endian(header.char_value);
	header.float_value 	= to_little_endian(header.float_value);
}

you can replace the type with the target endinan type:

using namespace byte_order;
struct header {
	big_int 		int_value;
	little_short	short_value;
	big_char		char_value; // makes little sence i know...
	litte_float		float_value;
};

void load_header(void *data,heade *&header) {
	header = reinterpret_cast<header *>(data);
	// no convert step needed, types of the headers members convert the data on read / write if needed
}

This moves the definition of the byte layout of the source data from 'load_header' to the definition
of 'header' and makes the code much cleaner and safer.