/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * aintl(x)     return x chopped to integral value
 * anintl(x)    return sign(x)*(|x|+0.5) chopped to integral value
 * irintl(x)    return rint(x) in integer format
 * nintl(x)     return anint(x) in integer format
 *
 * NOTE: aintl(x), anintl(x), ceill(x), floorl(x), and rintl(x) return result
 * with the same sign as x's,  including 0.0.
 */

#include "libm.h"
#include "longdouble.h"

extern enum fp_direction_type __swapRD(enum fp_direction_type);

static const long double qone = 1.0L, qhalf = 0.5L, qmhalf = -0.5L;

long double
aintl(long double x) {
        long double t, w;

        if (!finitel(x))
                return (x + x);
        w = fabsl(x);
        t = rintl(w);
        if (t <= w)
                return (copysignl(t, x));       /* NaN or already aint(|x|) */
        else    /* |t|>|x| case */
                return (copysignl(t - qone, x));        /* |t-1|*sign(x) */
}

long double
anintl(long double x) {
        long double t, w, z;

        if (!finitel(x))
                return (x + x);
        w = fabsl(x);
        t = rintl(w);
        if (t == w)
                return (copysignl(t, x));
        z = t - w;
        if (z > qhalf)
                t = t - qone;
        else if (z <= qmhalf)
                t = t + qone;
        return (copysignl(t, x));
}

int
irintl(long double x) {
        enum fp_direction_type rd;

        rd = __swapRD(fp_nearest);
        (void) __swapRD(rd);    /* restore Rounding Direction */
        switch (rd) {
        case fp_nearest:
                if (x < 2147483647.5L && x >= -2147483648.5L)
                        return ((int)rintl(x));
                break;
        case fp_tozero:
                if (x < 2147483648.0L && x > -2147483649.0L)
                        return ((int)rintl(x));
                break;
        case fp_positive:
                if (x <= 2147483647.0L && x > -2147483649.0L)
                        return ((int)rintl(x));
                break;
        case fp_negative:
                if (x < 2147483648.0L && x >= -2147483648.0L)
                        return ((int)rintl(x));
                break;
        }
        return ((int)copysignl(1.0e100L, x));
}

int
nintl(long double x) {
        if ((x < 2147483647.5L) && (x > -2147483648.5L))
                return ((int)anintl(x));
        else
                return ((int)copysignl(1.0e100L, x));
}