standard.c

ecos实时嵌入式操作系统

//===========================================================================
//
//      signgam.cxx
//
//      Support sign of the gamma*() functions in Math library
//
//===========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//===========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   jlarmour
// Contributors:  jlarmour
// Date:        1998-02-13
// Purpose:     
// Description: Contains the accessor functions to get and set the stored sign
//              of the gamma*() functions in the math library
// Usage:       
//
//####DESCRIPTIONEND####
//
//===========================================================================

/* @(#)k_standard.c 1.3 95/01/18 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunSoft, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice 
 * is preserved.
 * ====================================================
 *
 */

// CONFIGURATION

#include <pkgconf/libm.h>   // Configuration header

// Include the Math library?
#ifdef CYGPKG_LIBM

// INCLUDES

#include <cyg/infra/cyg_type.h>    // Common type definitions and support
#include <cyg/infra/cyg_trac.h>    // Tracing macros

#include <math.h>                  // Main header for math library
#include "mathincl/fdlibm.h"       // Internal header for math library

#include <cyg/error/codes.h>       // standard error codes

#ifndef CYGSEM_LIBM_COMPAT_IEEE_ONLY
#include <errno.h>
#else
static int errno; // this whole file won't be used if we're IEEE only, but
                  // doing this keeps the compiler happy
#endif

#ifdef CYGSEM_LIBM_USE_STDERR

#include <stdio.h>
#define WRITE2(u,v)     fputs(u, stderr)

#else

#define WRITE2(u,v)     0

#endif // ifdef CYGSEM_LIBM_USE_STDERR


// GLOBALS

static const double zero = 0.0;

// FUNCTIONS

/* 
 * Standard conformance (non-IEEE) on exception cases.
 * Mapping:
 *      1 -- acos(|x|>1)
 *      2 -- asin(|x|>1)
 *      3 -- atan2(+-0,+-0)
 *      4 -- hypot overflow
 *      5 -- cosh overflow
 *      6 -- exp overflow
 *      7 -- exp underflow
 *      8 -- y0(0)
 *      9 -- y0(-ve)
 *      10-- y1(0)
 *      11-- y1(-ve)
 *      12-- yn(0)
 *      13-- yn(-ve)
 *      14-- lgamma(finite) overflow
 *      15-- lgamma(-integer)
 *      16-- log(0)
 *      17-- log(x<0)
 *      18-- log10(0)
 *      19-- log10(x<0)
 *      20-- pow(0.0,0.0)
 *      21-- pow(x,y) overflow
 *      22-- pow(x,y) underflow
 *      23-- pow(0,negative) 
 *      24-- pow(neg,non-integral)
 *      25-- sinh(finite) overflow
 *      26-- sqrt(negative)
 *      27-- fmod(x,0)
 *      28-- remainder(x,0)
 *      29-- acosh(x<1)
 *      30-- atanh(|x|>1)
 *      31-- atanh(|x|=1)
 *      32-- scalb overflow
 *      33-- scalb underflow
 *      34-- j0(|x|>X_TLOSS)
 *      35-- y0(x>X_TLOSS)
 *      36-- j1(|x|>X_TLOSS)
 *      37-- y1(x>X_TLOSS)
 *      38-- jn(|x|>X_TLOSS, n)
 *      39-- yn(x>X_TLOSS, n)
 *      40-- gamma(finite) overflow
 *      41-- gamma(-integer)
 *      42-- pow(NaN,0.0)
 *      43-- ldexp overflow
 *      44-- ldexp underflow
 */


double
__kernel_standard(double x, double y, int type) 
{
        struct exception exc;

#ifdef CYGSEM_LIBM_USE_STDERR
        (void) fflush(stdout);
#endif
        exc.arg1 = x;
        exc.arg2 = y;
        switch(type) {
            case 1:
                /* acos(|x|>1) */
                exc.type = DOMAIN;
                exc.name = "acos";
                exc.retval = zero;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = EDOM;
                else if (!matherr(&exc)) {
                  if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID) {
                    (void) WRITE2("acos: DOMAIN error\n", 19);
                  }
                  errno = EDOM;
                }
                break;
            case 2:
                /* asin(|x|>1) */
                exc.type = DOMAIN;
                exc.name = "asin";
                exc.retval = zero;
                if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = EDOM;
                else if (!matherr(&exc)) {
                  if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID) {
                        (void) WRITE2("asin: DOMAIN error\n", 19);
                  }
                  errno = EDOM;
                }
                break;
            case 3:
                /* atan2(+-0,+-0) */
                exc.arg1 = y;
                exc.arg2 = x;
                exc.type = DOMAIN;
                exc.name = "atan2";
                exc.retval = zero;
                if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = EDOM;
                else if (!matherr(&exc)) {
                  if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID) {
                        (void) WRITE2("atan2: DOMAIN error\n", 20);
                      }
                  errno = EDOM;
                }
                break;
            case 4:
                /* hypot(finite,finite) overflow */
                exc.type = OVERFLOW;
                exc.name = "hypot";
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID)
                  exc.retval = HUGE;
                else
                  exc.retval = HUGE_VAL;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = ERANGE;
                else if (!matherr(&exc)) {
                        errno = ERANGE;
                }
                break;
            case 5:
                /* cosh(finite) overflow */
                exc.type = OVERFLOW;
                exc.name = "cosh";
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID)
                  exc.retval = HUGE;
                else
                  exc.retval = HUGE_VAL;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = ERANGE;
                else if (!matherr(&exc)) {
                        errno = ERANGE;
                }
                break;
            case 6:
                /* exp(finite) overflow */
                exc.type = OVERFLOW;
                exc.name = "exp";
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID)
                  exc.retval = HUGE;
                else
                  exc.retval = HUGE_VAL;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = ERANGE;
                else if (!matherr(&exc)) {
                        errno = ERANGE;
                }
                break;
            case 7:
                /* exp(finite) underflow */
                exc.type = UNDERFLOW;
                exc.name = "exp";
                exc.retval = zero;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = ERANGE;
                else if (!matherr(&exc)) {
                        errno = ERANGE;
                }
                break;
            case 8:
                /* y0(0) = -inf */
                exc.type = DOMAIN;      /* should be SING for IEEE */
                exc.name = "y0";
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_SVID)
                  exc.retval = -HUGE;
                else
                  exc.retval = -HUGE_VAL;
                if (cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_POSIX)
                  errno = EDOM;
                else if (!matherr(&exc)) {