# strchrnul.m4 serial 9

dnl Copyright (C) 2003, 2007, 2009-2015 Free Software Foundation, Inc.

dnl This file is free software; the Free Software Foundation

dnl gives unlimited permission to copy and/or distribute it,

dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_STRCHRNUL],

[

  dnl Persuade glibc <string.h> to declare strchrnul().

  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])

  AC_CHECK_FUNCS([strchrnul])

  if test $ac_cv_func_strchrnul = no; then

    HAVE_STRCHRNUL=0

  else

    AC_CACHE_CHECK([whether strchrnul works],

      [gl_cv_func_strchrnul_works],

      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[

#include <string.h> /* for strchrnul */

]], [[const char *buf = "a";

      return strchrnul (buf, 'b') != buf + 1;

    ]])],

        [gl_cv_func_strchrnul_works=yes],

        [gl_cv_func_strchrnul_works=no],

        [dnl Cygwin 1.7.9 introduced strchrnul, but it was broken until 1.7.10

         AC_EGREP_CPP([Lucky user],

           [

#if defined __CYGWIN__

 #include <cygwin/version.h>

 #if CYGWIN_VERSION_DLL_COMBINED > CYGWIN_VERSION_DLL_MAKE_COMBINED (1007, 9)

  Lucky user

 #endif

#else

  Lucky user

#endif

           ],

           [gl_cv_func_strchrnul_works="guessing yes"],

           [gl_cv_func_strchrnul_works="guessing no"])

        ])

      ])

    case "$gl_cv_func_strchrnul_works" in

      *yes) ;;

      *) REPLACE_STRCHRNUL=1 ;;

    esac

  fi

])

# Prerequisites of lib/strchrnul.c.

AC_DEFUN([gl_PREREQ_STRCHRNUL], [:])