/**
 * Credit card validation using Luhn check algorithm
 *
 * @file	platon/misc/luhnchk.h
 * @author	Gizmo <gizmo@hysteria.sk>
 * @author	Ondrej Jombik <nepto@platon.sk>
 * @version	\$Platon: libplaton/platon/misc/luhnchk.h,v 1.10 2003/04/23 19:01:37 nepto Exp $
 * @date	2000-2003
 */

/*	Updates:

	10/10/2000
	9/11/2000
	5/10/2001
	4/2/2002
	19/4/2002
	20/9/2002 - Doxygen documentation added
*/

#ifndef _PLATON_MISC_LUHNCHK_H
#define _PLATON_MISC_LUHNCHK_H

#define luhnchk(__s) luhncheck(__s)	/**< alias to luhncheck() */

#ifdef __cplusplus
extern "C" {
#endif

	/**
	 * Checks number according to Luhn check algorithm
	 *
	 * @param	number	number to check (ie. credit card number)
	 * @return	1 if number is valid, 0 otherwise
	 *
	 * Function is useful check credit cards numbers. All credit cards must
	 * pass this algorithm. Luhn check algorithm is published on several
	 * places, and also here:
     *
	 *      http://www.webopedia.com/TERM/L/Luhn_formula.html				<br>
	 *      http://www.merriampark.com/anatomycc.htm						<br>
	 *      http://hysteria.sk/prielom/prielom-12.html#3 (Slovak language)	<br>
	 *      http://www.speech.cs.cmu.edu/~sburke/pub/luhn_lib.html (Perl lib)
	 */
	int luhncheck(const char *number);

#ifdef __cplusplus
}
#endif

#endif /* #ifndef _PLATON_MISC_LUHNCHK_H */