# Look up an environment variable more securely.

dnl Copyright 2013-2020 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_SECURE_GETENV],

[

  dnl Persuade glibc <stdlib.h> to declare secure_getenv().

  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])

  AC_CHECK_FUNCS_ONCE([secure_getenv])

  if test $ac_cv_func_secure_getenv = no; then

    HAVE_SECURE_GETENV=0

  fi

])

# Prerequisites of lib/secure_getenv.c.

AC_DEFUN([gl_PREREQ_SECURE_GETENV], [

  AC_CHECK_FUNCS([__secure_getenv])

  if test $ac_cv_func___secure_getenv = no; then

    AC_CHECK_FUNCS([issetugid])

  fi

  AC_CHECK_FUNCS_ONCE([getuid geteuid getgid getegid])

])