/* Wrapper to set errno for tgamma.

   Copyright (C) 2017-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   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, see

   <http://www.gnu.org/licenses/>.  */

/* Only build wrappers from the templates for the types that define the macro

   below.  This macro is set in math-type-macros-<type>.h in sysdeps/generic

   for each floating-point type.  */

#if __USE_WRAPPER_TEMPLATE

# include <errno.h>

# include <fenv.h>

# include <math.h>

# include <math_private.h>

#define M_CALL_FUNC_X(x) x ## _r

#define M_CALL_FUNC(x) M_CALL_FUNC_X (x)

FLOAT

M_DECL_FUNC (__tgamma) (FLOAT x)

{

  int local_signgam;

  FLOAT y = M_CALL_FUNC (M_SUF (__ieee754_gamma)) (x, &local_signgam);

  if (__glibc_unlikely (!isfinite (y) || y == 0)

      && (isfinite (x) || (isinf (x) && x < 0)))

    {

      if (x == 0)

	/* Pole error: tgamma(x=0).  */

	__set_errno (ERANGE);

      else if (M_SUF (__floor) (x) == x && x < 0)

	/* Domain error: tgamma(integer x<0).  */

	__set_errno (EDOM);

      else

	/* Overflow or underflow.  */

	__set_errno (ERANGE);

    }

  return local_signgam < 0 ? -y : y;

}

declare_mgen_alias (__tgamma, tgamma)

#endif /* __USE_WRAPPER_TEMPLATE.  */