root/tools/regression/lib/libm/test-nan.c
/*-
 * Copyright (C) 2007 David Schultz <das@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: src/tools/regression/lib/msun/test-nan.c,v 1.1 2007/12/16 21:19:51 das Exp $
 */

/*
 * Test for nan(), nanf(), and nanl(). We also test that strtod("nan(...)")
 * and sscanf("nan(...)", ...) work identically.
 */

#include <assert.h>
#include <fenv.h>
#include <float.h>
#include <locale.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void
testnan(const char *nan_format)
{
        char nan_str[128];
        char *end;
        long double ald[4];
        double ad[4];
        float af[4];
        int i;

        snprintf(nan_str, sizeof(nan_str), "nan(%s)", nan_format);
        for (i = 0; i < 4; i++) {
                /*
                 * x86 has an 80-bit long double stored in 96 bits,
                 * so we need to initialize the memory for the memcmp()
                 * checks below to work.
                 */
                bzero(&af[i], sizeof(float));
                bzero(&ad[i], sizeof(double));
                bzero(&ald[i], sizeof(long double));

        }

        af[0] = nanf(nan_format);
        assert(isnan(af[0]));
        af[1] = strtof(nan_str, &end);
        assert(end == nan_str + strlen(nan_str));
        assert(sscanf(nan_str, "%e", &af[2]) == 1);
        assert(memcmp(&af[0], &af[1], sizeof(float)) == 0);
        assert(memcmp(&af[1], &af[2], sizeof(float)) == 0);
        if (*nan_format == '\0') {
                /* nanf("") == strtof("nan") */
                af[3] = strtof("nan", NULL);
                assert(memcmp(&af[2], &af[3], sizeof(float)) == 0);
        }

        ad[0] = nan(nan_format);
        assert(isnan(ad[0]));
        ad[1] = strtod(nan_str, &end);
        assert(end == nan_str + strlen(nan_str));
        assert(sscanf(nan_str, "%le", &ad[2]) == 1);
        assert(memcmp(&ad[0], &ad[1], sizeof(double)) == 0);
        assert(memcmp(&ad[1], &ad[2], sizeof(double)) == 0);
        if (*nan_format == '\0') {
                /* nan("") == strtod("nan") */
                ad[3] = strtod("nan", NULL);
                assert(memcmp(&ad[2], &ad[3], sizeof(double)) == 0);
        }

        ald[0] = nanl(nan_format);
        assert(isnan(ald[0]));
        ald[1] = strtold(nan_str, &end);
        assert(end == nan_str + strlen(nan_str));
        assert(sscanf(nan_str, "%Le", &ald[2]) == 1);
        assert(memcmp(&ald[0], &ald[1], sizeof(long double)) == 0);
        assert(memcmp(&ald[1], &ald[2], sizeof(long double)) == 0);
        if (*nan_format == '\0') {
                /* nanl("") == strtold("nan") */
                ald[3] = strtold("nan", NULL);
                assert(memcmp(&ald[2], &ald[3], sizeof(long double)) == 0);
        }
}

int
main(int argc, char *argv[])
{

        printf("1..1\n");

        /* Die if a signalling NaN is returned */
        feenableexcept(FE_INVALID);

        testnan("0x1234");
        testnan("");

        printf("ok 1 - nan\n");

        return (0);
}