getopt: new Autom4te::Getopt module

* lib/Autom4te/General.pm (getopt): Move the guts of its
implementation ...
* lib/Autom4te/Getopt.pm (parse_options): .. into this function
in the new Autom4te::Getopt module.  This will make it simpler
for the implementation to be shared with other projects (right
now, Automake).
* lib/Automake/Makefile.am (dist_perllib_DATA): Add the new
module.

3 files changed, 123 insertions, 41 deletions

diff --git a/lib/Autom4te/General.pm b/lib/Autom4te/General.pm
index f05042f6..0f93042d 100644
--- a/lib/Autom4te/General.pm
+++ b/lib/Autom4te/General.pm
@@ -36,6 +36,7 @@ use 5.006_002;
 use Exporter;
 use Autom4te::ChannelDefs;
 use Autom4te::Channels;
+use Autom4te::Getopt ();
 use File::Basename;
 use File::Path ();
 use File::stat;
@@ -232,12 +233,10 @@ sub debug (@)
 
 =item C<getopt (%option)>
 
-Wrapper around C<Getopt::Long>.  In addition to the user C<option>s,
-support C<-h>/C<--help>, C<-V>/C<--version>, C<-v>/C<--verbose>,
-C<-d>/C<--debug>, C<-f>/C<--force>.  Conform to the GNU Coding
-Standards for error messages.  Try to work around a weird behavior
-from C<Getopt::Long> to preserve C<-> as an C<@ARGV> instead of
-rejecting it as a broken option.
+Wrapper around C<Autom4te::Getopt::parse_options>.  In addition to
+the user C<option>s, support C<-h>/C<--help>, C<-V>/C<--version>,
+C<-v>/C<--verbose>, C<-d>/C<--debug>, C<-f>/C<--force>.  Conform to
+the GNU Coding Standards for error messages.
 
 =cut
 
@@ -247,8 +246,6 @@ rejecting it as a broken option.
 sub getopt (%)
 {
   my (%option) = @_;
-  use Getopt::Long;
-
   %option = ("h|help"     => sub { print $help; exit 0 },
 	     "V|version"  => sub { print $version; exit 0 },
 
@@ -258,39 +255,7 @@ sub getopt (%)
 
 	     # User options last, so that they have precedence.
 	     %option);
-  Getopt::Long::Configure ("bundling", "pass_through");
-  GetOptions (%option)
-    or exit 1;
-
-  # FIXME: Lot of code duplication with automake here.  It would probably
-  # be best to generalize our getopt() func and rip it out in a new module
-  # from which automake can sync.
-  if (@ARGV && $ARGV[0] =~ /^-./)
-    {
-      my %argopts;
-      for my $k (keys %option)
-	{
-	  if ($k =~ /(.*)=s$/)
-	    {
-	      map { $argopts{(length ($_) == 1)
-			     ? "-$_" : "--$_" } = 1; } (split (/\|/, $1));
-	    }
-	}
-      if ($ARGV[0] eq '--')
-	{
-	  shift @ARGV;
-	}
-      elsif (exists $argopts{$ARGV[0]})
-	{
-	  fatal ("option `$ARGV[0]' requires an argument\n"
-		 . "Try `$0 --help' for more information.");
-	}
-      else
-	{
-	  fatal ("unrecognized option `$ARGV[0]'.\n"
-		 . "Try `$0 --help' for more information.");
-	}
-    }
+  Autom4te::Getopt::parse_options (%option);
 
   setup_channel 'note', silent => !$verbose;
   setup_channel 'verb', silent => !$verbose;
diff --git a/lib/Autom4te/Getopt.pm b/lib/Autom4te/Getopt.pm
new file mode 100644
index 00000000..77f21db0
--- /dev/null
+++ b/lib/Autom4te/Getopt.pm
@@ -0,0 +1,116 @@
+# Copyright (C) 2012 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package Autom4te::Getopt;
+
+=head1 NAME
+
+Autom4te::Getopt - GCS conforming parser for command line options
+
+=head1 SYNOPSIS
+
+  use Autom4te::Getopt;
+
+=head1 DESCRIPTION
+
+Export a function C<parse_options>, performing parsing of command
+line options in conformance to the GNU Conding standards.
+
+=cut
+
+use 5.006_002;
+use strict;
+use warnings FATAL => 'all';
+use Exporter ();
+use Getopt::Long ();
+use Autom4te::ChannelDefs qw/fatal/;
+use Carp qw/croak confess/;
+
+use vars qw (@ISA @EXPORT);
+@ISA = qw (Exporter);
+@EXPORT= qw/getopt/;
+
+=item C<parse_options (%option)>
+
+Wrapper around C<Getopt::Long>, trying to conform to the GNU
+Coding Standards for error messages.
+
+=cut
+
+sub parse_options (%)
+{
+  my %option = @_;
+
+  Getopt::Long::Configure ("bundling", "pass_through");
+  # Unrecognized options are passed through, so GetOption can only fail
+  # due to internal errors or misuse of options specification.
+  Getopt::Long::GetOptions (%option)
+    or confess "error in options specification (likely)";
+
+  if (@ARGV && $ARGV[0] =~ /^-./)
+    {
+      my %argopts;
+      for my $k (keys %option)
+	{
+	  if ($k =~ /(.*)=s$/)
+	    {
+	      map { $argopts{(length ($_) == 1)
+			     ? "-$_" : "--$_" } = 1; } (split (/\|/, $1));
+	    }
+	}
+      if ($ARGV[0] eq '--')
+	{
+	  shift @ARGV;
+	}
+      elsif (exists $argopts{$ARGV[0]})
+	{
+	  fatal ("option `$ARGV[0]' requires an argument\n"
+		 . "Try `$0 --help' for more information.");
+	}
+      else
+	{
+	  fatal ("unrecognized option `$ARGV[0]'.\n"
+		 . "Try `$0 --help' for more information.");
+	}
+    }
+
+}
+
+=back
+
+=head1 SEE ALSO
+
+L<Getopt::Long>
+
+=cut
+
+1; # for require
+
+### Setup "GNU" style for perl-mode and cperl-mode.
+## Local Variables:
+## perl-indent-level: 2
+## perl-continued-statement-offset: 2
+## perl-continued-brace-offset: 0
+## perl-brace-offset: 0
+## perl-brace-imaginary-offset: 0
+## perl-label-offset: -2
+## cperl-indent-level: 2
+## cperl-brace-offset: 0
+## cperl-continued-brace-offset: 0
+## cperl-label-offset: -2
+## cperl-extra-newline-before-brace: t
+## cperl-merge-trailing-else: nil
+## cperl-continued-statement-offset: 2
+## End:
diff --git a/lib/Autom4te/Makefile.am b/lib/Autom4te/Makefile.am
index ff15fb81..c82cc3fa 100644
--- a/lib/Autom4te/Makefile.am
+++ b/lib/Autom4te/Makefile.am
@@ -23,6 +23,7 @@ dist_perllib_DATA = \
   Configure_ac.pm \
   FileUtils.pm \
   General.pm \
+  Getopt.pm \
   Request.pm \
   Struct.pm \
   XFile.pm