/* ABI compatibility for lgamma functions.

   Copyright (C) 2015-2018 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/>.  */

#ifndef LGAMMA_COMPAT_H

#define LGAMMA_COMPAT_H 1

#include <math-svid-compat.h>

#include <shlib-compat.h>

/* XSI POSIX requires lgamma to set signgam, but ISO C does not permit

   this.  Namespace issues can be avoided if the functions set

   __signgam and signgam is a weak alias, but this only works if both

   signgam and __signgam were exported from the glibc version the

   program was linked against.  Before glibc 2.23, lgamma functions

   set signgam which was not a weak alias for __signgam, so old

   binaries have dynamic symbols for signgam only and the versions of

   lgamma used for old binaries must set both signgam and __signgam.

   Those versions also do a check of _LIB_VERSION != _ISOC_ to match

   old glibc.

   Users of this file define USE_AS_COMPAT to 0 when building the main

   version of lgamma, 1 when building the compatibility version.  */

#define LGAMMA_OLD_VER GLIBC_2_0

#define LGAMMA_NEW_VER GLIBC_2_23

#define HAVE_LGAMMA_COMPAT SHLIB_COMPAT (libm, LGAMMA_OLD_VER, LGAMMA_NEW_VER)

/* Whether to build this version at all.  */

#define BUILD_LGAMMA \

  (LIBM_SVID_COMPAT && (HAVE_LGAMMA_COMPAT || !USE_AS_COMPAT))

/* The name to use for this version.  */

#if USE_AS_COMPAT

# define LGFUNC(FUNC) FUNC ## _compat

#else

# define LGFUNC(FUNC) FUNC

#endif

/* If there is a compatibility version, gamma (not an ISO C function,

   so never a problem for it to set signgam) points directly to it

   rather than having separate versions.  */

#define GAMMA_ALIAS (USE_AS_COMPAT ? HAVE_LGAMMA_COMPAT : !HAVE_LGAMMA_COMPAT)

/* How to call the underlying lgamma_r function.  */

#define CALL_LGAMMA(TYPE, FUNC, ARG)			\

  ({							\

    TYPE lgamma_tmp;					\

    int local_signgam;					\

    if (USE_AS_COMPAT)					\

      {							\

	lgamma_tmp = FUNC ((ARG), &local_signgam);	\

	if (_LIB_VERSION != _ISOC_)			\

	  signgam = __signgam = local_signgam;		\

      }							\

    else						\

      lgamma_tmp = FUNC ((ARG), &__signgam);		\

    lgamma_tmp;						\

  })

#endif /* lgamma-compat.h.  */