/*	$OpenBSD: util.h,v 1.4 2006/01/08 21:10:04 miod Exp $	*/

/*-
 * Copyright (c) 1994
 *	The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1994, 1995, 1996
 *	Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 *
 *	@(#)util.h	10.5 (Berkeley) 3/16/96
 */

/* Macros to init/set/clear/test flags. */
#define	FL_INIT(l, f)	(l) = (f)		/* Specific flags location. */
#define	FL_SET(l, f)	((l) |= (f))
#define	FL_CLR(l, f)	((l) &= ~(f))
#define	FL_ISSET(l, f)	((l) & (f))

#define	LF_INIT(f)	FL_INIT(flags, (f))	/* Local variable flags. */
#define	LF_SET(f)	FL_SET(flags, (f))
#define	LF_CLR(f)	FL_CLR(flags, (f))
#define	LF_ISSET(f)	FL_ISSET(flags, (f))

#define	F_INIT(p, f)	FL_INIT((p)->flags, (f))	/* Structure element flags. */
#define	F_SET(p, f)	FL_SET((p)->flags, (f))
#define	F_CLR(p, f)	FL_CLR((p)->flags, (f))
#define	F_ISSET(p, f)	FL_ISSET((p)->flags, (f))

/* Offset to next column of stop size, e.g. tab offsets. */
#define	COL_OFF(c, stop)	((stop) - ((c) % (stop)))

/* Busy message types. */
typedef enum { B_NONE, B_OFF, B_READ, B_RECOVER, B_SEARCH, B_WRITE } bmsg_t;

/*
 * Number handling defines and protoypes.
 *
 * NNFITS:	test for addition of two negative numbers under a limit
 * NPFITS:	test for addition of two positive numbers under a limit
 * NADD_SLONG:	test for addition of two signed longs
 * NADD_USLONG:	test for addition of two unsigned longs
 */
enum nresult { NUM_ERR, NUM_OK, NUM_OVER, NUM_UNDER };
#define	NNFITS(min, cur, add)						\
	(((long)(min)) - (cur) <= (add))
#define	NPFITS(max, cur, add)						\
	(((unsigned long)(max)) - (cur) >= (add))
#define	NADD_SLONG(v1, v2)						\
	((v1) < 0 ?							\
	    ((v2) < 0 &&						\
	    NNFITS(LONG_MIN, (v1), (v2))) ? NUM_UNDER : NUM_OK :	\
	 (v1) > 0 ?							\
	    (v2) > 0 &&							\
	    NPFITS(LONG_MAX, (v1), (v2)) ? NUM_OK : NUM_OVER :		\
	 NUM_OK)