#!./miniperl -w
# vim: syntax=perl
#
# configpm
#
# Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007 Larry Wall and others.
#
#
# Regenerate the files
#
#    lib/Config.pm
#    lib/Config_heavy.pl
#    lib/Config.pod
#
#
# from the contents of the static files
#
#    Porting/Glossary
#    myconfig.SH
#
# and from the contents of the Configure-generated file
#
#    config.sh
#
#
# It will only update Config.pm and Config_heavy.pl if the contents of
# either file would be different. Note that *both* files are updated in
# this case, since for example an extension makefile that has a dependency
# on Config.pm should trigger even if only Config_heavy.pl has changed.

sub uncomment($) { 
    return $_[0]=~s/^#(?:    )?//mgr;
}

sub usage { die uncomment <<EOF }
#    usage: $0  [ options ]
#        --no-glossary       don't include Porting/Glossary in lib/Config.pod
#        --chdir=dir         change directory before writing files
EOF

use strict;
our (%Config, $Config_SH_expanded);

my $how_many_common = 22;

# commonly used names to precache (and hence lookup fastest)
my %Common;

while ($how_many_common--) {
    $_ = <DATA>;
    chomp;
    /^(\S+):\s*(\d+)$/ or die "Malformed line '$_'";
    $Common{$1} = $1;
}

# Post 37589e1eefb1bd62 DynaLoader defaults to reading these at runtime.
# Ideally we're redo the data below, but Fotango's build system made it
# wonderfully easy to instrument, and no longer exists.
$Common{$_} = $_ foreach qw(dlext so);

# names of things which may need to have slashes changed to double-colons
my %Extensions = map {($_,$_)}
                 qw(dynamic_ext static_ext extensions known_extensions);

# The plan is that this information is used by ExtUtils::MakeMaker to generate
# Makefile dependencies, rather than hardcoding a list, which has become out
# of date. However, currently, MM_Unix.pm and MM_VMS.pm have *different* lists,
# *and* descrip_mms.template doesn't actually install all the headers.
# The "Unix" list seems to (attempt to) avoid the generated headers, which I'm
# not sure is the right thing to do. Also, not certain whether it would be
# easier to parse MANIFEST to get these (adding config.h, and potentially
# removing others), but for now, stick to a hard coded list.

# Could use a map to add ".h", but I suspect that it's easier to use literals,
# so that anyone using grep will find them
# This is the list from MM_VMS, plus pad.h, parser.h, utf8.h
# which it installs. It *doesn't* install perliol.h - FIXME.
my @header_files = qw(EXTERN.h INTERN.h XSUB.h av.h config.h cop.h cv.h
		      embed.h embedvar.h form.h gv.h handy.h hv.h hv_func.h intrpvar.h
		      iperlsys.h keywords.h mg.h nostdio.h op.h opcode.h
		      pad.h parser.h patchlevel.h perl.h perlio.h perlsdio.h
		      perlvars.h perly.h pp.h pp_proto.h proto.h
		      regcomp.h regexp.h regnodes.h scope.h sv.h thread.h utf8.h
		      util.h);

push @header_files,
    $^O eq 'VMS' ? 'vmsish.h' : qw(dosish.h perliol.h time64.h unixish.h);

my $header_files = '    return qw(' . join(' ', sort @header_files) . ');';
$header_files =~ s/(?=.{64})   # If line is still overlength
		   (.{1,64})\  # Split at the last convenient space
		  /$1\n              /gx;

# allowed opts as well as specifies default and initial values
my %Allowed_Opts = (
    'glossary' => 1,  # --no-glossary  - no glossary file inclusion,
                      #                  for compactness
    'chdir'    => '', # --chdir=dir    - change directory before writing files
);

sub opts {
    # user specified options
    my %given_opts = (
        # --opt=smth
        (map {/^--([\-_\w]+)=(.*)$/} @ARGV),
        # --opt --no-opt --noopt
        (map {/^no-?(.*)$/i?($1=>0):($_=>1)} map {/^--([\-_\w]+)$/} @ARGV),
    );

    my %opts = (%Allowed_Opts, %given_opts);

    for my $opt (grep {!exists $Allowed_Opts{$_}} keys %given_opts) {
        warn "option '$opt' is not recognized";
	usage;
    }
    @ARGV = grep {!/^--/} @ARGV;

    return %opts;
}


my %Opts = opts();

if ($Opts{chdir}) {
    chdir $Opts{chdir} or die "$0: could not chdir $Opts{chdir}: $!"
}

my ($Config_SH, $Config_PM, $Config_heavy, $Config_POD);
my $Glossary = 'Porting/Glossary';

$Config_PM = "lib/Config.pm";
$Config_POD = "lib/Config.pod";
$Config_SH = "config.sh";

($Config_heavy = $Config_PM) =~ s/\.pm$/_heavy.pl/;
die "Can't automatically determine name for Config_heavy.pl from '$Config_PM'"
  if $Config_heavy eq $Config_PM;

my $config_txt;
my $heavy_txt;

my $export_funcs = uncomment <<'EOT';
#    my %Export_Cache = (myconfig => 1, config_sh => 1, config_vars => 1,
#                        config_re => 1, compile_date => 1, local_patches => 1,
#                        bincompat_options => 1, non_bincompat_options => 1,
#                        header_files => 1);
EOT

my %export_ok = eval $export_funcs or die;

$config_txt .= sprintf uncomment << 'EOT', $], $export_funcs;
#    # This file was created by configpm when Perl was built. Any changes
#    # made to this file will be lost the next time perl is built.
#
#    # for a description of the variables, please have a look at the
#    # Glossary file, as written in the Porting folder, or use the url:
#    # https://github.com/Perl/perl5/blob/blead/Porting/Glossary
#
#    package Config;
#    use strict;
#    use warnings;
#    our ( %%Config, $VERSION );
#
#    $VERSION = "%s";
#
#    # Skip @Config::EXPORT because it only contains %%Config, which we special
#    # case below as it's not a function. @Config::EXPORT won't change in the
#    # lifetime of Perl 5.
#    %s
#    @Config::EXPORT = qw(%%Config);
#    @Config::EXPORT_OK = keys %%Export_Cache;
#
#    # Need to stub all the functions to make code such as print Config::config_sh
#    # keep working
#
EOT

$config_txt .= "sub $_;\n" foreach sort keys %export_ok;

my $myver = sprintf "%vd", $^V;

$config_txt .= sprintf uncomment <<'ENDOFBEG', ($myver) x 3;
#
#    # Define our own import method to avoid pulling in the full Exporter:
#    sub import {
#        shift;
#        @_ = @Config::EXPORT unless @_;
#
#        my @funcs = grep $_ ne '%%Config', @_;
#        my $export_Config = @funcs < @_ ? 1 : 0;
#
#        no strict 'refs';
#        my $callpkg = caller(0);
#        foreach my $func (@funcs) {
#            die qq{"$func" is not exported by the Config module\n}
#                unless $Export_Cache{$func};
#            *{$callpkg.'::'.$func} = \&{$func};
#        }
#
#        *{"$callpkg\::Config"} = \%%Config if $export_Config;
#        return;
#    }
#
#    die "$0: Perl lib version (%s) doesn't match executable '$^X' version ($])"
#        unless $^V;
#
#    $^V eq %s
#        or die sprintf "%%s: Perl lib version (%s) doesn't match executable '$^X' version (%%vd)", $0, $^V;
#
ENDOFBEG


my @non_v    = ();
my @v_others = ();
my $in_v     = 0;
my %Data     = ();
my $quote;

# These variables were set in older versions of Perl, but are no longer needed
# by the core. However, some CPAN modules may rely on them; in particular, Tk
# (at least up to version 804.034) fails to build without them. We force them
# to be emitted to Config_heavy.pl for backcompat with such modules (and we may
# find that this set needs to be extended in future). See RT#132347.
my @v_forced = map "$_\n", split /\n+/, uncomment <<'EOT';
#    i_limits='define'
#    i_stdlib='define'
#    i_string='define'
#    i_time='define'
#    prototype='define'
EOT


my %seen_quotes;
{
  my ($name, $val);
  open(CONFIG_SH, '<', $Config_SH) || die "Can't open $Config_SH: $!";
  while (<CONFIG_SH>) {
    next if m:^#!/bin/sh:;

    # Catch PERL_CONFIG_SH=true and PERL_VERSION=n line from Configure.
    s/^(\w+)=(true|\d+)\s*$/$1='$2'\n/ or m/^(\w+)='(.*)'$/;
    my($k, $v) = ($1, $2);

    # grandfather PATCHLEVEL and SUBVERSION and CONFIG
    if ($k) {
	if ($k eq 'PERL_VERSION') {
	    push @v_others, "PATCHLEVEL='$v'\n";
	}
	elsif ($k eq 'PERL_SUBVERSION') {
	    push @v_others, "SUBVERSION='$v'\n";
	}
	elsif ($k eq 'PERL_CONFIG_SH') {
	    push @v_others, "CONFIG='$v'\n";
	}
    }

    # We can delimit things in config.sh with either ' or ". 
    unless ($in_v or m/^(\w+)=(['"])(.*\n)/){
	push(@non_v, "#$_"); # not a name='value' line
	next;
    }
    if ($in_v) { 
        $val .= $_;
    }
    else { 
	$quote = $2;
        ($name,$val) = ($1,$3); 
	if ($name eq 'cc') {
	    $val =~ s{^(['"]?+).*\bccache\s+}{$1};
	}
    }
    $in_v = $val !~ /$quote\n/;
    next if $in_v;

    s,/,::,g if $Extensions{$name};

    $val =~ s/$quote\n?\z//;

    my $line = "$name=$quote$val$quote\n";
    push(@v_others, $line);
    $seen_quotes{$quote}++;
  }
  close CONFIG_SH;
}

# This is somewhat grim, but I want the code for parsing config.sh here and
# now so that I can expand $Config{ivsize} and $Config{ivtype}

my $fetch_string = uncomment <<'EOT';
#
#    # Search for it in the big string
#    sub fetch_string {
#        my($self, $key) = @_;
#
EOT

if ($seen_quotes{'"'}) {
    # We need the full ' and " code

$fetch_string .= uncomment <<'EOT';
#        return undef unless my ($quote_type, $value) = $Config_SH_expanded =~ /\n$key=(['"])(.*?)\1\n/s;
#
#        # If we had a double-quote, we'd better eval it so escape
#        # sequences and such can be interpolated. Since the incoming
#        # value is supposed to follow shell rules and not perl rules,
#        # we escape any perl variable markers
#
#        # Historically, since " 'support' was added in change 1409, the
#        # interpolation was done before the undef. Stick to this arguably buggy
#        # behaviour as we're refactoring.
#        if ($quote_type eq '"') {
#            $value =~ s/\$/\\\$/g;
#            $value =~ s/\@/\\\@/g;
#            eval "\$value = \"$value\"";
#        }
#
#        # So we can say "if $Config{'foo'}".
#        $self->{$key} = $value eq 'undef' ? undef : $value; # cache it
#    }
EOT

} else {
    # We only have ' delimited.

$fetch_string .= uncomment <<'EOT';
#        return undef unless $Config_SH_expanded =~ /\n$key=\'(.*?)\'\n/s;
#        # So we can say "if $Config{'foo'}".
#        $self->{$key} = $1 eq 'undef' ? undef : $1;
#    }
EOT

}

eval $fetch_string;
die if $@;

# Calculation for the keys for byteorder
# This is somewhat grim, but I need to run fetch_string here.
$Config_SH_expanded = join "\n", '', @v_others;

my $t = fetch_string ({}, 'ivtype');
my $s = fetch_string ({}, 'ivsize');

# byteorder does exist on its own but we overlay a virtual
# dynamically recomputed value.

# However, ivtype and ivsize will not vary for sane fat binaries

my $f = $t eq 'long' ? 'L!' : $s == 8 ? 'Q': 'I';

my $byteorder_code;
if ($s == 4 || $s == 8) {
    my $list = join ',', reverse(1..$s-1);
    my $format = 'a'x$s;
    $byteorder_code = <<"EOT";

my \$i = ord($s);
foreach my \$c ($list) { \$i <<= 8; \$i |= ord(\$c); }
our \$byteorder = join('', unpack('$format', pack('$f', \$i)));
EOT
} else {
    $byteorder_code = "our \$byteorder = '?'x$s;\n";
}

my @need_relocation;

if (fetch_string({},'userelocatableinc')) {
    foreach my $what (qw(prefixexp

			 archlibexp
			 html1direxp
			 html3direxp
			 man1direxp
			 man3direxp
			 privlibexp
			 scriptdirexp
			 sitearchexp
			 sitebinexp
			 sitehtml1direxp
			 sitehtml3direxp
			 sitelibexp
			 siteman1direxp
			 siteman3direxp
			 sitescriptexp
			 vendorarchexp
			 vendorbinexp
			 vendorhtml1direxp
			 vendorhtml3direxp
			 vendorlibexp
			 vendorman1direxp
			 vendorman3direxp
			 vendorscriptexp

			 siteprefixexp
			 sitelib_stem
			 vendorlib_stem

			 installarchlib
			 installhtml1dir
			 installhtml3dir
			 installman1dir
			 installman3dir
			 installprefix
			 installprefixexp
			 installprivlib
			 installscript
			 installsitearch
			 installsitebin
			 installsitehtml1dir
			 installsitehtml3dir
			 installsitelib
			 installsiteman1dir
			 installsiteman3dir
			 installsitescript
			 installvendorarch
			 installvendorbin
			 installvendorhtml1dir
			 installvendorhtml3dir
			 installvendorlib
			 installvendorman1dir
			 installvendorman3dir
			 installvendorscript
			 )) {
	push @need_relocation, $what if fetch_string({}, $what) =~ m!^\.\.\./!;
    }
}

my %need_relocation;
@need_relocation{@need_relocation} = @need_relocation;

# This can have .../ anywhere:
if (fetch_string({}, 'otherlibdirs') =~ m!\.\.\./!) {
    $need_relocation{otherlibdirs} = 'otherlibdirs';
}

my $relocation_code = uncomment <<'EOT';
#
#    sub relocate_inc {
#      my $libdir = shift;
#      return $libdir unless $libdir =~ s!^\.\.\./!!;
#      my $prefix = $^X;
#      if ($prefix =~ s!/[^/]*$!!) {
#        while ($libdir =~ m!^\.\./!) {
#          # Loop while $libdir starts "../" and $prefix still has a trailing
#          # directory
#          last unless $prefix =~ s!/([^/]+)$!!;
#          # but bail out if the directory we picked off the end of $prefix is .
#          # or ..
#          if ($1 eq '.' or $1 eq '..') {
#            # Undo! This should be rare, hence code it this way rather than a
#            # check each time before the s!!! above.
#            $prefix = "$prefix/$1";
#            last;
#          }
#          # Remove that leading ../ and loop again
#          substr ($libdir, 0, 3, '');
#        }
#        $libdir = "$prefix/$libdir";
#      }
#      $libdir;
#    }
EOT

my $osname = fetch_string({}, 'osname');
my $from = $osname eq 'VMS' ? 'PERLSHR image' : 'binary (from libperl)';
my $env_cygwin = $osname eq 'cygwin'
    ? 'push @env, "CYGWIN=\"$ENV{CYGWIN}\"" if $ENV{CYGWIN};' . "\n" : "";

$heavy_txt .= sprintf uncomment <<'ENDOFBEG', $osname, $osname, $from, $osname, $env_cygwin;
#    # This file was created by configpm when Perl was built. Any changes
#    # made to this file will be lost the next time perl is built.
#
#    package Config;
#    use strict;
#    use warnings;
#    our %%Config;
#
#    sub bincompat_options {
#        return split ' ', (Internals::V())[0];
#    }
#
#    sub non_bincompat_options {
#        return split ' ', (Internals::V())[1];
#    }
#
#    sub compile_date {
#        return (Internals::V())[2]
#    }
#
#    sub local_patches {
#        my (undef, undef, undef, @patches) = Internals::V();
#        return @patches;
#    }
#
#    sub _V {
#        die "Perl lib was built for '%s' but is being run on '$^O'"
#            unless "%s" eq $^O;
#
#        my ($bincompat, $non_bincompat, $date, @patches) = Internals::V();
#
#        my @opts = sort split ' ', "$bincompat $non_bincompat";
#
#        print Config::myconfig();
#        print "\nCharacteristics of this %s: \n";
#
#        print "  Compile-time options:\n";
#        print "    $_\n" for @opts;
#
#        if (@patches) {
#            print "  Locally applied patches:\n";
#            print "    $_\n" foreach @patches;
#        }
#
#        print "  Built under %s\n";
#
#        print "  $date\n" if defined $date;
#
#        my @env = map { "$_=\"$ENV{$_}\"" } sort grep {/^PERL/} keys %%ENV;
#    %s
#        if (@env) {
#            print "  \%%ENV:\n";
#            print "    $_\n" foreach @env;
#        }
#        print "  \@INC:\n";
#        print "    $_\n" foreach @INC;
#    }
#
#    sub header_files {
ENDOFBEG

$heavy_txt .= $header_files . "\n}\n\n";

if (%need_relocation) {
  my $relocations_in_common;
  # otherlibdirs only features in the hash
  foreach (keys %need_relocation) {
    $relocations_in_common++ if $Common{$_};
  }
  if ($relocations_in_common) {
    $config_txt .= $relocation_code;
  } else {
    $heavy_txt .= $relocation_code;
  }
}

$heavy_txt .= join('', @non_v) . "\n";

# copy config summary format from the myconfig.SH script
$heavy_txt .= "our \$summary = <<'!END!';\n";
open(MYCONFIG,'<','myconfig.SH') || die "open myconfig.SH failed: $!";
1 while defined($_ = <MYCONFIG>) && !/^Summary of/;
do { $heavy_txt .= $_ } until !defined($_ = <MYCONFIG>) || /^\s*$/;
close(MYCONFIG);

$heavy_txt .= "\n!END!\n" . uncomment <<'EOT';
#    my $summary_expanded;
#
#    sub myconfig {
#        return $summary_expanded if $summary_expanded;
#        ($summary_expanded = $summary) =~ s{\$(\w+)}
#                     {
#                            my $c;
#                            if ($1 eq 'git_ancestor_line') {
#                                    if ($Config::Config{git_ancestor}) {
#                                            $c= "\n  Ancestor: $Config::Config{git_ancestor}";
#                                    } else {
#                                            $c= "";
#                                    }
#                            } else {
#                                    $c = $Config::Config{$1};
#                            }
#                            defined($c) ? $c : 'undef'
#                    }ge;
#        $summary_expanded;
#    }
#
#    local *_ = \my $a;
#    $_ = <<'!END!';
EOT
#proper lexicographical order of the keys
my %seen_var;
my @v_define = ( "taint_support=''\n",
                 "taint_disabled=''\n" );
$heavy_txt .= join('',
    map { $_->[-1] }
    sort {$a->[0] cmp $b->[0] }
    grep { !$seen_var{ $_->[0] }++ }
    map {
        /^([^=]+)/ ? [ $1, $_ ]
                   : [ $_, $_ ] # shouldnt happen
    } (@v_others, @v_forced, @v_define)
) . "!END!\n";

# Only need the dynamic byteorder code in Config.pm if 'byteorder' is one of
# the precached keys
if ($Common{byteorder}) {
    $config_txt .= $byteorder_code;
} else {
    $heavy_txt .= $byteorder_code;
}

$heavy_txt .= uncomment <<'EOT';
#    s/(byteorder=)(['"]).*?\2/$1$2$Config::byteorder$2/m;
#
EOT

$heavy_txt .= uncomment <<'EOF_TAINT_INIT';
#    {
#        # We have to set this up late as Win32 does not build miniperl
#        # with the same defines and CC flags as it builds perl itself.
#        my $defines = join " ", (Internals::V)[0,1];
#        if (
#            $defines =~ /\b(SILENT_NO_TAINT_SUPPORT)\b/ ||
#            $defines =~ /\b(NO_TAINT_SUPPORT)\b/
#        ){
#            my $which = $1;
#            my $taint_disabled = ($which eq "SILENT_NO_TAINT_SUPPORT")
#                                 ? "silent" : "define";
#            s/^(taint_disabled=['"])(["'])/$1$taint_disabled$2/m;
#        }
#        else {
#            my $taint_support = 'define';
#            s/^(taint_support=['"])(["'])/$1$taint_support$2/m;
#        }
#    }
EOF_TAINT_INIT

if (@need_relocation) {
$heavy_txt .= 'foreach my $what (qw(' . join (' ', @need_relocation) .
      ")) {\n" . uncomment <<'EOT';
#        s/^($what=)(['"])(.*?)\2/$1 . $2 . relocate_inc($3) . $2/me;
#    }
EOT
# Currently it only makes sense to do the ... relocation on Unix, so there's
# no need to emulate the "which separator for this platform" logic in perl.c -
# ':' will always be applicable
if ($need_relocation{otherlibdirs}) {
$heavy_txt .= uncomment << 'EOT';
#    s{^(otherlibdirs=)(['"])(.*?)\2}
#     {$1 . $2 . join ':', map {relocate_inc($_)} split ':', $3 . $2}me;
EOT
}
}

$heavy_txt .= uncomment <<'EOT';
#    my $config_sh_len = length $_;
#
#    our $Config_SH_expanded = "\n$_" . << 'EOVIRTUAL';
EOT

foreach my $prefix (qw(ccflags ldflags)) {
    my $value = fetch_string ({}, $prefix);
    my $withlargefiles = fetch_string ({}, $prefix . "_uselargefiles");
    if (defined $withlargefiles) {
        $value =~ s/\Q$withlargefiles\E\b//;
        $heavy_txt .= "${prefix}_nolargefiles='$value'\n";
    }
}

foreach my $prefix (qw(libs libswanted)) {
    my $value = fetch_string ({}, $prefix);
    my $withlf = fetch_string ({}, 'libswanted_uselargefiles');
    next unless defined $withlf;
    my @lflibswanted
       = split(' ', fetch_string ({}, 'libswanted_uselargefiles'));
    if (@lflibswanted) {
	my %lflibswanted;
	@lflibswanted{@lflibswanted} = ();
	if ($prefix eq 'libs') {
	    my @libs = grep { /^-l(.+)/ &&
                            not exists $lflibswanted{$1} }
		                    split(' ', fetch_string ({}, 'libs'));
	    $value = join(' ', @libs);
	} else {
	    my @libswanted = grep { not exists $lflibswanted{$_} }
	                          split(' ', fetch_string ({}, 'libswanted'));
	    $value = join(' ', @libswanted);
	}
    }
    $heavy_txt .= "${prefix}_nolargefiles='$value'\n";
}

if (open(my $fh, '<', 'cflags')) {
    my $ccwarnflags;
    my $ccstdflags;
    while (<$fh>) {
        if (/^warn="(.+)"$/) {
            $ccwarnflags = $1;
        } elsif (/^stdflags="(.+)"$/) {
            $ccstdflags = $1;
        }
    }
    if (defined $ccwarnflags) {
      $heavy_txt .= "ccwarnflags='$ccwarnflags'\n";
    }
    if (defined $ccstdflags) {
      $heavy_txt .= "ccstdflags='$ccstdflags'\n";
    }
}

$heavy_txt .= "EOVIRTUAL\n";

$heavy_txt .= uncomment <<'ENDOFGIT';
#    eval {
#            # do not have hairy conniptions if this isnt available
#            require 'Config_git.pl';
#            $Config_SH_expanded .= $Config::Git_Data;
#            1;
#    } or warn "Warning: failed to load Config_git.pl, something strange about this perl...\n";
ENDOFGIT

$heavy_txt .= $fetch_string;

$config_txt .= uncomment <<'ENDOFEND';
#
#    sub FETCH {
#        my($self, $key) = @_;
#
#        # check for cached value (which may be undef so we use exists not defined)
#        return exists $self->{$key} ? $self->{$key} : $self->fetch_string($key);
#    }
#
ENDOFEND

$heavy_txt .= uncomment <<'ENDOFEND';
#
#    my $prevpos = 0;
#
#    sub FIRSTKEY {
#        $prevpos = 0;
#        substr($Config_SH_expanded, 1, index($Config_SH_expanded, '=') - 1 );
#    }
#
#    sub NEXTKEY {
ENDOFEND
if ($seen_quotes{'"'}) {
$heavy_txt .= uncomment <<'ENDOFEND';
#        # Find out how the current key's quoted so we can skip to its end.
#        my $quote = substr($Config_SH_expanded,
#                           index($Config_SH_expanded, "=", $prevpos)+1, 1);
#        my $pos = index($Config_SH_expanded, qq($quote\n), $prevpos) + 2;
ENDOFEND
} else {
    # Just ' quotes, so it's much easier.
$heavy_txt .= uncomment <<'ENDOFEND';
#        my $pos = index($Config_SH_expanded, qq('\n), $prevpos) + 2;
ENDOFEND
}
$heavy_txt .= uncomment <<'ENDOFEND';
#        my $len = index($Config_SH_expanded, "=", $pos) - $pos;
#        $prevpos = $pos;
#        $len > 0 ? substr($Config_SH_expanded, $pos, $len) : undef;
#    }
#
#    sub EXISTS {
#        return 1 if exists($_[0]->{$_[1]});
#
#        return(index($Config_SH_expanded, "\n$_[1]='") != -1
ENDOFEND
if ($seen_quotes{'"'}) {
$heavy_txt .= uncomment <<'ENDOFEND';
#               or index($Config_SH_expanded, "\n$_[1]=\"") != -1
ENDOFEND
}
$heavy_txt .= uncomment <<'ENDOFEND';
#              );
#    }
#
#    sub STORE  { die "\%Config::Config is read-only\n" }
#    *DELETE = *CLEAR = \*STORE; # Typeglob aliasing uses less space
#
#    sub config_sh {
#        substr $Config_SH_expanded, 1, $config_sh_len;
#    }
#
#    sub config_re {
#        my $re = shift;
#        return map { chomp; $_ } grep eval{ /^(?:$re)=/ }, split /^/,
#        $Config_SH_expanded;
#    }
#
#    sub config_vars {
#        # implements -V:cfgvar option (see perlrun -V:)
#        foreach (@_) {
#            # find optional leading, trailing colons; and query-spec
#            my ($notag,$qry,$lncont) = m/^(:)?(.*?)(:)?$/;  # flags fore and aft,
#            # map colon-flags to print decorations
#            my $prfx = $notag ? '': "$qry=";                # tag-prefix for print
#            my $lnend = $lncont ? ' ' : ";\n";              # line ending for print
#
#            # all config-vars are by definition \w only, any \W means regex
#            if ($qry =~ /\W/) {
#                my @matches = config_re($qry);
#                print map "$_$lnend", @matches ? @matches : "$qry: not found"               if !$notag;
#                print map { s/\w+=//; "$_$lnend" } @matches ? @matches : "$qry: not found"  if  $notag;
#            } else {
#                my $v = (exists $Config::Config{$qry}) ? $Config::Config{$qry}
#                                                       : 'UNKNOWN';
#                $v = 'undef' unless defined $v;
#                print "${prfx}'${v}'$lnend";
#            }
#        }
#    }
#
#    # Called by the real AUTOLOAD
#    sub launcher {
#        undef &AUTOLOAD;
#        goto \&$Config::AUTOLOAD;
#    }
#
#    1;
ENDOFEND

if ($^O eq 'os2') {
    $config_txt .= uncomment <<'ENDOFSET';
#    my %preconfig;
#    if ($OS2::is_aout) {
#        my ($value, $v) = $Config_SH_expanded =~ m/^used_aout='(.*)'\s*$/m;
#        for (split ' ', $value) {
#            ($v) = $Config_SH_expanded =~ m/^aout_$_='(.*)'\s*$/m;
#            $preconfig{$_} = $v eq 'undef' ? undef : $v;
#        }
#    }
#    $preconfig{d_fork} = undef unless $OS2::can_fork; # Some funny cases can't
#    sub TIEHASH { bless {%preconfig} }
ENDOFSET
    # Extract the name of the DLL from the makefile to avoid duplication
    my ($f) = grep -r, qw(GNUMakefile Makefile);
    my $dll;
    if (open my $fh, '<', $f) {
	while (<$fh>) {
	    $dll = $1, last if /^PERL_DLL_BASE\s*=\s*(\S*)\s*$/;
	}
    }
    $config_txt .= uncomment <<ENDOFSET if $dll;
#    \$preconfig{dll_name} = '$dll';
ENDOFSET
} else {
    $config_txt .= uncomment <<'ENDOFSET';
#    sub TIEHASH {
#        bless $_[1], $_[0];
#    }
ENDOFSET
}

foreach my $key (keys %Common) {
    my $value = fetch_string ({}, $key);
    # Is it safe on the LHS of => ?
    my $qkey = $key =~ /^[A-Za-z_][A-Za-z0-9_]*$/ ? $key : "'$key'";
    if (defined $value) {
	# Quote things for a '' string
	$value =~ s!\\!\\\\!g;
	$value =~ s!'!\\'!g;
	$value = "'$value'";
	if ($key eq 'otherlibdirs') {
	    $value = "join (':', map {relocate_inc(\$_)} split (':', $value))";
	} elsif ($need_relocation{$key}) {
	    $value = "relocate_inc($value)";
	}
    } else {
	$value = "undef";
    }
    $Common{$key} = "$qkey => $value";
}

if ($Common{byteorder}) {
    $Common{byteorder} = 'byteorder => $byteorder';
}
my $fast_config = join '', map { "    $_,\n" } sort values %Common;

# Sanity check needed to stop an infinite loop if Config_heavy.pl fails to
# define &launcher for some reason (eg it got truncated)
$config_txt .= sprintf uncomment <<'ENDOFTIE', $fast_config;
#
#    sub DESTROY { }
#
#    sub AUTOLOAD {
#        require 'Config_heavy.pl';
#        goto \&launcher unless $Config::AUTOLOAD =~ /launcher$/;
#        die "&Config::AUTOLOAD failed on $Config::AUTOLOAD";
#    }
#
#    # tie returns the object, so the value returned to require will be true.
#    tie %%Config, 'Config', {
#    %s};
ENDOFTIE


open(CONFIG_POD, '>:raw', $Config_POD) or die "Can't open $Config_POD: $!";
print CONFIG_POD uncomment <<'ENDOFTAIL';
#    =head1 NAME
#
#    =for comment  Generated by configpm.  Any changes made here will be lost!
#
#    Config - access Perl configuration information
#
#    =head1 SYNOPSIS
#
#        use Config;
#        if ($Config{usethreads}) {
#            print "has thread support\n"
#        }
#
#        use Config qw(myconfig config_sh config_vars config_re);
#
#        print myconfig();
#
#        print config_sh();
#
#        print config_re();
#
#        config_vars(qw(osname archname));
#
#
#    =head1 DESCRIPTION
#
#    The Config module contains all the information that was available to
#    the F<Configure> program at Perl build time (over 900 values).
#
#    Shell variables from the F<config.sh> file (written by Configure) are
#    stored in the readonly-variable C<%Config>, indexed by their names.
#
#    Values stored in config.sh as 'undef' are returned as undefined
#    values.  The perl C<exists> function can be used to check if a
#    named variable exists.
#
#    For a description of the variables, please have a look at the
#    Glossary file, as written in the Porting folder, or use the url:
#    https://github.com/Perl/perl5/blob/blead/Porting/Glossary
#
#    =over 4
#
#    =item myconfig()
#
#    Returns a textual summary of the major perl configuration values.
#    See also C<-V> in L<perlrun/Command Switches>.
#
#    =item config_sh()
#
#    Returns the entire perl configuration information in the form of the
#    original config.sh shell variable assignment script.
#
#    =item config_re($regex)
#
#    Like config_sh() but returns, as a list, only the config entries who's
#    names match the $regex.
#
#    =item config_vars(@names)
#
#    Prints to STDOUT the values of the named configuration variable. Each is
#    printed on a separate line in the form:
#
#      name='value';
#
#    Names which are unknown are output as C<name='UNKNOWN';>.
#    See also C<-V:name> in L<perlrun/Command Switches>.
#
#    =item bincompat_options()
#
#    Returns a list of C pre-processor options used when compiling this F<perl>
#    binary, which affect its binary compatibility with extensions.
#    C<bincompat_options()> and C<non_bincompat_options()> are shown together in
#    the output of C<perl -V> as I<Compile-time options>.
#
#    =item non_bincompat_options()
#
#    Returns a list of C pre-processor options used when compiling this F<perl>
#    binary, which do not affect binary compatibility with extensions.
#
#    =item compile_date()
#
#    Returns the compile date (as a string), equivalent to what is shown by
#    C<perl -V>
#
#    =item local_patches()
#
#    Returns a list of the names of locally applied patches, equivalent to what
#    is shown by C<perl -V>.
#
#    =item header_files()
#
#    Returns a list of the header files that should be used as dependencies for
#    XS code, for this version of Perl on this platform.
#
#    =back
#
#    =head1 EXAMPLE
#
#    Here's a more sophisticated example of using %Config:
#
#        use Config;
#        use strict;
#
#        my %sig_num;
#        my @sig_name;
#        unless($Config{sig_name} && $Config{sig_num}) {
#            die "No sigs?";
#        } else {
#            my @names = split ' ', $Config{sig_name};
#            @sig_num{@names} = split ' ', $Config{sig_num};
#            foreach (@names) {
#                $sig_name[$sig_num{$_}] ||= $_;
#            }
#        }
#
#        print "signal #17 = $sig_name[17]\n";
#        if ($sig_num{ALRM}) {
#            print "SIGALRM is $sig_num{ALRM}\n";
#        }
#
#    =head1 WARNING
#
#    Because this information is not stored within the perl executable
#    itself it is possible (but unlikely) that the information does not
#    relate to the actual perl binary which is being used to access it.
#
#    The Config module is installed into the architecture and version
#    specific library directory ($Config{installarchlib}) and it checks the
#    perl version number when loaded.
#
#    The values stored in config.sh may be either single-quoted or
#    double-quoted. Double-quoted strings are handy for those cases where you
#    need to include escape sequences in the strings. To avoid runtime variable
#    interpolation, any C<$> and C<@> characters are replaced by C<\$> and
#    C<\@>, respectively. This isn't foolproof, of course, so don't embed C<\$>
#    or C<\@> in double-quoted strings unless you're willing to deal with the
#    consequences. (The slashes will end up escaped and the C<$> or C<@> will
#    trigger variable interpolation)
#
#    =head1 GLOSSARY
#
#    Most C<Config> variables are determined by the C<Configure> script
#    on platforms supported by it (which is most UNIX platforms).  Some
#    platforms have custom-made C<Config> variables, and may thus not have
#    some of the variables described below, or may have extraneous variables
#    specific to that particular port.  See the port specific documentation
#    in such cases.
#
#    =cut
#
ENDOFTAIL

if ($Opts{glossary}) {
  open(GLOS, '<', $Glossary) or die "Can't open $Glossary: $!";
}
my $text = 0;
$/ = '';
my $errors= 0;

my %glossary;

my $fc;
my $item;

sub process {
  if (s/\A(\w*)\s+\(([\w.]+)\):\s*\n(\t?)/=item C<$1>\n\nFrom F<$2>:\n\n/m) {
    $item = $1;
    $fc = substr $item, 0, 1;
  }
  elsif (!$item || !/\A\t/) {
    warn "Expected a Configure variable header",
      ($text ? " or another paragraph of description" : () ),
      ", instead we got:\n$_";
    $errors++;
  }
  s/n't/n\00t/g;		# leave can't, won't etc untouched
  s/^\t\s+(.*)/\n$1/gm;		# Indented lines ===> new paragraph
  s/^(?<!\n\n)\t(.*)/$1/gm;	# Not indented lines ===> text
  s{([\'\"])(?=[^\'\"\s]*[./][^\'\"\s]*\1)([^\'\"\s]+)\1}(F<$2>)g; # '.o'
  s{([\'\"])([^\'\"\s]+)\1}(C<$2>)g; # "date" command
  s{\'([A-Za-z_\- *=/]+)\'}(C<$1>)g; # 'ln -s'
  s{
     (?<! [\w./<\'\"\$] )		# Only standalone file names
     (?! e \. g \. )		# Not e.g.
     (?! \. \. \. )		# Not ...
     (?! \d )			# Not 5.004
     (?! read/ )		# Not read/write
     (?! etc\. )		# Not etc.
     (?! I/O )			# Not I/O
     (
	\$ ?			# Allow leading $
	[\w./]* [./] [\w./]*	# Require . or / inside
     )
     (?<! \. (?= [\s)] ) )	# Do not include trailing dot
     (?! [\w/] )		# Include all of it
   }
   (F<$1>)xg;			# /usr/local
  s/((?<=\s)~\w*)/F<$1>/g;	# ~name
  s/(?<![.<\'\"])\b([A-Z_]{2,})\b(?![\'\"])/C<$1>/g;	# UNISTD
  s/(?<![.<\'\"])\b(?!the\b)(\w+)\s+macro\b/C<$1> macro/g; # FILE_cnt macro
  s/n[\0]t/n't/g;		# undo can't, won't damage
  $glossary{$fc}{$item} .= $_;
}

if ($Opts{glossary}) {
    <GLOS>;				# Skip the "DO NOT EDIT"
    <GLOS>;				# Skip the preamble
  while (<GLOS>) {
    process;
  }
  if ($errors) {
    die "Errors encountered while processing $Glossary. ",
        "Header lines are expected to be of the form:\n",
        "NAME (CLASS):\n",
        "Maybe there is a malformed header?\n",
    ;
  }
}

$glossary{t}{taint_support} //= uncomment <<EOF_TEXT;
#    =item C<taint_support>
#
#    From define: C<SILENT_NO_TAINT_SUPPORT> or C<NO_TAINT_SUPPORT>
#
#    If this perl is compiled with support for taint mode this variable will
#    be set to 'define', if it is not it will be set to the empty string.
#    Either of the above defines will result in it being empty.  This property
#    was added in version 5.37.11. See also L</taint_disabled>.
#
EOF_TEXT

$glossary{t}{taint_disabled} //= uncomment <<EOF_TEXT;
#    =item C<taint_disabled>
#
#    From define: C<SILENT_NO_TAINT_SUPPORT> or C<NO_TAINT_SUPPORT>
#
#    If this perl is compiled with support for taint mode this variable will
#    be set to the empty string, if it was compiled with
#    C<SILENT_NO_TAINT_SUPPORT> defined then it will be set to be "silent",
#    and if it was compiled with C<NO_TAINT_SUPPORT> defined it will be
#    'define'. Either of the above defines will results in it being a true
#    value. This property was added in 5.37.11. See also L</taint_support>.
#
EOF_TEXT

if ($Opts{glossary}) {
    foreach my $fc (sort keys %glossary) {
        print CONFIG_POD "=head2 $fc\n\n=over 4\n\n";
        foreach my $item (sort keys %{$glossary{$fc}}) {
            print CONFIG_POD $glossary{$fc}{$item};
        }
        print CONFIG_POD "=back\n\n";
    }
}

print CONFIG_POD uncomment <<'ENDOFTAIL';
#
#    =head1 GIT DATA
#
#    Information on the git commit from which the current perl binary was compiled
#    can be found in the variable C<$Config::Git_Data>.  The variable is a
#    structured string that looks something like this:
#
#      git_commit_id='ea0c2dbd5f5ac6845ecc7ec6696415bf8e27bd52'
#      git_describe='GitLive-blead-1076-gea0c2db'
#      git_branch='smartmatch'
#      git_uncommitted_changes=''
#      git_commit_id_title='Commit id:'
#      git_commit_date='2009-05-09 17:47:31 +0200'
#
#    Its format is not guaranteed not to change over time.
#
#    =head1 NOTE
#
#    This module contains a good example of how to use tie to implement a
#    cache and an example of how to make a tied variable readonly to those
#    outside of it.
#
#    =cut
#
ENDOFTAIL

close(GLOS) if $Opts{glossary};
close(CONFIG_POD);
print "written $Config_POD\n";

my $orig_config_txt = "";
my $orig_heavy_txt = "";
{
    local $/;
    my $fh;
    $orig_config_txt = <$fh> if open $fh, "<", $Config_PM;
    $orig_heavy_txt  = <$fh> if open $fh, "<", $Config_heavy;
}

if ($orig_config_txt ne $config_txt or $orig_heavy_txt ne $heavy_txt) {
    open CONFIG, ">", $Config_PM or die "Can't open $Config_PM: $!\n";
    open CONFIG_HEAVY, ">", $Config_heavy or die "Can't open $Config_heavy: $!\n";
    print CONFIG $config_txt;
    print CONFIG_HEAVY $heavy_txt;
    close(CONFIG_HEAVY);
    close(CONFIG);
    print "updated $Config_PM\n";
    print "updated $Config_heavy\n";
}

# Now do some simple tests on the Config.pm file we have created
unshift(@INC,'lib');
require $Config_PM;
require $Config_heavy;
import Config;

die "$0: $Config_PM not valid"
	unless $Config{'PERL_CONFIG_SH'} eq 'true';

die "$0: error processing $Config_PM"
	if defined($Config{'an impossible name'})
	or $Config{'PERL_CONFIG_SH'} ne 'true' # test cache
	;

die "$0: error processing $Config_PM"
	if eval '$Config{"cc"} = 1'
	or eval 'delete $Config{"cc"}'
	;


exit 0;
# Popularity of various entries in %Config, based on a large build and test
# run of code in the Fotango build system:
__DATA__
path_sep:	8490
d_readlink:	7101
d_symlink:	7101
archlibexp:	4318
sitearchexp:	4305
sitelibexp:	4305
privlibexp:	4163
ldlibpthname:	4041
libpth:	2134
archname:	1591
exe_ext:	1256
scriptdir:	1155
version:	1116
useithreads:	1002
osvers:	982
osname:	851
inc_version_list:	783
dont_use_nlink:	779
intsize:	759
usevendorprefix:	642
dlsrc:	624
cc:	541
lib_ext:	520
so:	512
ld:	501
ccdlflags:	500
ldflags:	495
obj_ext:	495
cccdlflags:	493
lddlflags:	493
ar:	492
dlext:	492
libc:	492
ranlib:	492
full_ar:	491
vendorarchexp:	491
vendorlibexp:	491
installman1dir:	489
installman3dir:	489
installsitebin:	489
installsiteman1dir:	489
installsiteman3dir:	489
installvendorman1dir:	489
installvendorman3dir:	489
d_flexfnam:	474
eunicefix:	360
d_link:	347
installsitearch:	344
installscript:	341
installprivlib:	337
binexp:	336
installarchlib:	336
installprefixexp:	336
installsitelib:	336
installstyle:	336
installvendorarch:	336
installvendorbin:	336
installvendorlib:	336
man1ext:	336
man3ext:	336
sh:	336
siteprefixexp:	336
installbin:	335
usedl:	332
ccflags:	285
startperl:	232
optimize:	231
usemymalloc:	229
cpprun:	228
sharpbang:	228
perllibs:	225
usesfio:	224
usethreads:	220
perlpath:	218
extensions:	217
usesocks:	208
shellflags:	198
make:	191
d_pwage:	189
d_pwchange:	189
d_pwclass:	189
d_pwcomment:	189
d_pwexpire:	189
d_pwgecos:	189
d_pwpasswd:	189
d_pwquota:	189
gccversion:	189
libs:	186
useshrplib:	186
cppflags:	185
ptrsize:	185
shrpenv:	185
static_ext:	185
uselargefiles:	185
alignbytes:	184
byteorder:	184
ccversion:	184
config_args:	184
cppminus:	184