m4/setenv.m4 reorganization

[Bruno Haible]

For the use of m4/setenv.m4 by the relocatable stuff, it is better if
the 'setenv' part and the 'unsetenv' part are separate (because the
wrapper program needs to set environment variables like LD_LIBRARY_PATH,
but never unsets them).


2007-03-03  Bruno Haible  <address@hidden>

        * m4/setenv.m4 (gl_FUNC_SETENV, gl_FUNC_UNSETENV): New macros,
        extracted from gt_FUNC_SETENV.
        (gt_FUNC_SETENV): Remove macro.
        * modules/setenv (configure.ac): Add gl_FUNC_SETENV, gl_FUNC_UNSETENV,
        remove gt_FUNC_SETENV.

*** m4/setenv.m4        17 Jun 2006 16:10:06 -0000      1.6
--- m4/setenv.m4        3 Mar 2007 19:04:52 -0000
***************
*** 1,16 ****
! # setenv.m4 serial 6
! dnl Copyright (C) 2001-2004, 2006 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([gt_FUNC_SETENV],
  [
!   AC_REPLACE_FUNCS(setenv unsetenv)
    if test $ac_cv_func_setenv = no; then
      gl_PREREQ_SETENV
    fi
    if test $ac_cv_func_unsetenv = no; then
      gl_PREREQ_UNSETENV
    else
      AC_CACHE_CHECK([for unsetenv() return type], gt_cv_func_unsetenv_ret,
--- 1,23 ----
! # setenv.m4 serial 7
! dnl Copyright (C) 2001-2004, 2006-2007 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_SETENV],
  [
!   AC_CHECK_FUNCS_ONCE([setenv])
    if test $ac_cv_func_setenv = no; then
+     AC_LIBOBJ([setenv])
      gl_PREREQ_SETENV
    fi
+ ])
+ 
+ AC_DEFUN([gl_FUNC_UNSETENV],
+ [
+   AC_CHECK_FUNCS([unsetenv])
    if test $ac_cv_func_unsetenv = no; then
+     AC_LIBOBJ([unsetenv])
      gl_PREREQ_UNSETENV
    else
      AC_CACHE_CHECK([for unsetenv() return type], gt_cv_func_unsetenv_ret,
*** modules/setenv      13 Oct 2006 12:40:23 -0000      1.11
--- modules/setenv      3 Mar 2007 19:04:52 -0000
***************
*** 14,20 ****
  unistd
  
  configure.ac:
! gt_FUNC_SETENV
  
  Makefile.am:
  
--- 14,21 ----
  unistd
  
  configure.ac:
! gl_FUNC_SETENV
! gl_FUNC_UNSETENV
  
  Makefile.am: