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[gnulib.git] / m4 / getopt.m4

diff --git a/m4/getopt.m4 b/m4/getopt.m4
index 79c6991..067838f 100644 (file)
--- a/m4/getopt.m4
+++ b/m4/getopt.m4
@@ -1,72 +1,87 @@
-# getopt.m4 serial 9
-dnl Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+# getopt.m4 serial 15
+dnl Copyright (C) 2002-2006, 2008-2009 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.
 
 # The getopt module assume you want GNU getopt, with getopt_long etc,
-# rather than vanilla POSIX getopt.  This means your your code should
+# rather than vanilla POSIX getopt.  This means your code should
 # always include <getopt.h> for the getopt prototypes.
 
 AC_DEFUN([gl_GETOPT_SUBSTITUTE],
 [
-  GETOPT_H=getopt.h
   AC_LIBOBJ([getopt])
   AC_LIBOBJ([getopt1])
+  gl_GETOPT_SUBSTITUTE_HEADER
+  gl_PREREQ_GETOPT
+])
+
+# emacs' configure.in uses this.
+AC_DEFUN([gl_GETOPT_SUBSTITUTE_HEADER],
+[
+  GETOPT_H=getopt.h
   AC_DEFINE([__GETOPT_PREFIX], [[rpl_]],
     [Define to rpl_ if the getopt replacement functions and variables
      should be used.])
   AC_SUBST([GETOPT_H])
 ])
 
-AC_DEFUN([gl_GETOPT],
+AC_DEFUN([gl_GETOPT_CHECK_HEADERS],
 [
-  gl_PREREQ_GETOPT
-
   if test -z "$GETOPT_H"; then
-    GETOPT_H=
     AC_CHECK_HEADERS([getopt.h], [], [GETOPT_H=getopt.h])
-    if test -z "$GETOPT_H"; then
-      AC_CHECK_FUNCS([getopt_long_only], [], [GETOPT_H=getopt.h])
-    fi
+  fi
 
-    dnl BSD getopt_long uses an incompatible method to reset option processing,
-    dnl and (as of 2004-10-15) mishandles optional option-arguments.
-    if test -z "$GETOPT_H"; then
-      AC_CHECK_DECL([optreset], [GETOPT_H=getopt.h], [], [#include <getopt.h>])
-    fi
+  if test -z "$GETOPT_H"; then
+    AC_CHECK_FUNCS([getopt_long_only], [], [GETOPT_H=getopt.h])
+  fi
 
-    dnl Solaris 10 getopt doesn't handle `+' as a leading character in an
-    dnl option string (as of 2005-05-05).
-    if test -z "$GETOPT_H"; then
-      AC_CACHE_CHECK([for working GNU getopt function], [gl_cv_func_gnu_getopt],
+  dnl BSD getopt_long uses an incompatible method to reset option processing,
+  dnl and (as of 2004-10-15) mishandles optional option-arguments.
+  if test -z "$GETOPT_H"; then
+    AC_CHECK_DECL([optreset], [GETOPT_H=getopt.h], [], [#include <getopt.h>])
+  fi
+
+  dnl Solaris 10 getopt doesn't handle `+' as a leading character in an
+  dnl option string (as of 2005-05-05).
+  if test -z "$GETOPT_H"; then
+    AC_CACHE_CHECK([for working GNU getopt function], [gl_cv_func_gnu_getopt],
       [AC_RUN_IFELSE(
-        [AC_LANG_PROGRAM([#include <getopt.h>],
+       [AC_LANG_PROGRAM([[#include <getopt.h>]],
           [[
             char *myargv[3];
             myargv[0] = "conftest";
             myargv[1] = "-+";
             myargv[2] = 0;
             return getopt (2, myargv, "+a") != '?';
-           ]])],
-        [gl_cv_func_gnu_getopt=yes],
-        [gl_cv_func_gnu_getopt=no],
-        [dnl cross compiling - pessimistically guess based on decls
-         dnl Solaris 10 getopt doesn't handle `+' as a leading character in an
-         dnl option string (as of 2005-05-05).
-         AC_CHECK_DECL([getopt_clip],
+          ]])],
+       [gl_cv_func_gnu_getopt=yes],
+       [gl_cv_func_gnu_getopt=no],
+       [dnl cross compiling - pessimistically guess based on decls
+        dnl Solaris 10 getopt doesn't handle `+' as a leading character in an
+        dnl option string (as of 2005-05-05).
+        AC_CHECK_DECL([getopt_clip],
           [gl_cv_func_gnu_getopt=no], [gl_cv_func_gnu_getopt=yes],
           [#include <getopt.h>])])])
-      if test "$gl_cv_func_gnu_getopt" = "no"; then
-       GETOPT_H=getopt.h
-      fi
-    fi
-
-    if test -n "$GETOPT_H"; then
-      gl_GETOPT_SUBSTITUTE
+    if test "$gl_cv_func_gnu_getopt" = "no"; then
+      GETOPT_H=getopt.h
     fi
   fi
 ])
 
+# emacs' configure.in uses this.
+AC_DEFUN([gl_GETOPT_IFELSE],
+[
+  AC_REQUIRE([gl_GETOPT_CHECK_HEADERS])
+  AS_IF([test -n "$GETOPT_H"], [$1], [$2])
+])
+
+# This is gnulib's entry-point.
+AC_DEFUN([gl_GETOPT], [gl_GETOPT_IFELSE([gl_GETOPT_SUBSTITUTE])])
+
 # Prerequisites of lib/getopt*.
-AC_DEFUN([gl_PREREQ_GETOPT], [:])
+# emacs' configure.in uses this.
+AC_DEFUN([gl_PREREQ_GETOPT],
+[
+  AC_CHECK_DECLS_ONCE([getenv])
+])