csu3_am335x/EVSE/GPL/plc-utils.LNX.2.1.20/source/tools/strdecr.c

/*====================================================================*
 *
 *   signed strdecr (void * memory, size_t extent, byte min, byte max);
 *
 *   memory.h
 *
 *   decrement a multi-byte memory region; start at max and reset at
 *   min; return -1 if all bytes are min;
 *
 *   Motley Tools by Charles Maier <cmaier@cmassoc.net>;
 *   Copyright (c) 2001-2006 by Charles Maier Associates;
 *   Licensed under the Internet Software Consortium License;
 *
 *--------------------------------------------------------------------*/

#ifndef STRDECR_SOURCE
#define STRDECR_SOURCE

#include "../tools/memory.h"

signed strdecr (void * memory, register size_t extent, register byte min, register byte max) 

{ 
	register byte * offset = (byte *) (memory); 
	while (extent--) 
	{ 
		if (-- offset [extent] >= min) 
		{ 
			return (0); 
		} 
		offset [extent] = max; 
	} 
	return (- 1); 
} 

#endif