source: trunk/libs/newlib/src/newlib/libc/sys/linux/cmath/s_csinf.c @ 444

/* Complex sine function for float.
   Copyright (C) 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <complex.h>
#include <fenv.h>
#include <math.h>

#include "math_private.h"


__complex__ float
__csinf (__complex__ float x)
{
  __complex__ float retval;
  int negate = signbit (__real__ x);
  int rcls = fpclassify (__real__ x);
  int icls = fpclassify (__imag__ x);

  __real__ x = fabsf (__real__ x);

  if (icls >= FP_ZERO)
    {
      /* Imaginary part is finite.  */
      if (rcls >= FP_ZERO)
        {
          /* Real part is finite.  */
          float sinh_val = __ieee754_sinhf (__imag__ x);
          float cosh_val = __ieee754_coshf (__imag__ x);
          float sinix, cosix;

          __sincosf (__real__ x, &sinix, &cosix);

          __real__ retval = cosh_val * sinix;
          __imag__ retval = sinh_val * cosix;

          if (negate)
            __real__ retval = -__real__ retval;
        }
      else
        {
          if (icls == FP_ZERO)
            {
              /* Imaginary part is 0.0.  */
              __real__ retval = __nanf ("");
              __imag__ retval = __imag__ x;

#ifdef FE_INVALID
              if (rcls == FP_INFINITE)
                feraiseexcept (FE_INVALID);
#endif
            }
          else
            {
              __real__ retval = __nanf ("");
              __imag__ retval = __nanf ("");

#ifdef FE_INVALID
              feraiseexcept (FE_INVALID);
#endif
            }
        }
    }
  else if (icls == FP_INFINITE)
    {
      /* Imaginary part is infinite.  */
      if (rcls == FP_ZERO)
        {
          /* Real part is 0.0.  */
          __real__ retval = __copysignf (0.0, negate ? -1.0 : 1.0);
          __imag__ retval = __imag__ x;
        }
      else if (rcls > FP_ZERO)
        {
          /* Real part is finite.  */
          float sinix, cosix;

          __sincosf (__real__ x, &sinix, &cosix);

          __real__ retval = __copysignf (HUGE_VALF, sinix);
          __imag__ retval = __copysignf (HUGE_VALF, cosix);

          if (negate)
            __real__ retval = -__real__ retval;
          if (signbit (__imag__ x))
            __imag__ retval = -__imag__ retval;
        }
      else
        {
          /* The addition raises the invalid exception.  */
          __real__ retval = __nanf ("");
          __imag__ retval = HUGE_VALF;

#ifdef FE_INVALID
          if (rcls == FP_INFINITE)
            feraiseexcept (FE_INVALID);
#endif
        }
    }
  else
    {
      if (rcls == FP_ZERO)
        __real__ retval = __copysignf (0.0, negate ? -1.0 : 1.0);
      else
        __real__ retval = __nanf ("");
      __imag__ retval = __nanf ("");
    }

  return retval;
}
weak_alias (__csinf, csinf)