PeerStreamer

#! /usr/bin/perl -w

#   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.

# This file is part of GNU CC.

# GNU CC 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 2, or (at your option)

# any later version.

# GNU CC 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 GNU CC; see the file COPYING.  If not, write to

# the Free Software Foundation, 51 Franklin Street, Fifth Floor,

# Boston, MA 02110-1301 USA

# This does trivial (and I mean _trivial_) conversion of Texinfo

# markup to Perl POD format.  It's intended to be used to extract

# something suitable for a manpage from a Texinfo document.

$output = 0;

$skipping = 0;

%sects = ();

@sects_sequence = ();

$section = "";

@icstack = ();

@endwstack = ();

@skstack = ();

@instack = ();

$shift = "";

%defs = ();

$fnno = 1;

$inf = "";

$ibase = "";

while ($_ = shift) {

    if (/^-D(.*)$/) {

        if ($1 ne "") {

            $flag = $1;

        } else {

            $flag = shift;

        }

        $value = "";

        ($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);

        die "no flag specified for -D\n"

            unless $flag ne "";

        die "flags may only contain letters, digits, hyphens, dashes and underscores\n"

            unless $flag =~ /^[a-zA-Z0-9_-]+$/;

        $defs{$flag} = $value;

    } elsif (/^-/) {

        usage();

    } else {

        $in = $_, next unless defined $in;

        $out = $_, next unless defined $out;

        usage();

    }

}

if (defined $in) {

    $inf = gensym();

    open($inf, "<$in") or die "opening \"$in\": $!\n";

    $ibase = $1 if $in =~ m|^(.+)/[^/]+$|;

} else {

    $inf = \*STDIN;

}

if (defined $out) {

    open(STDOUT, ">$out") or die "opening \"$out\": $!\n";

}

while(defined $inf) {

while(<$inf>) {

    # Certain commands are discarded without further processing.

    /^\@(?:

         [a-z]+index            # @*index: useful only in complete manual

         |need                  # @need: useful only in printed manual

         |(?:end\s+)?group      # @group .. @end group: ditto

         |page                  # @page: ditto

         |node                  # @node: useful only in .info file

         |(?:end\s+)?ifnottex   # @ifnottex .. @end ifnottex: use contents

        )\b/x and next;

    chomp;

    # Look for filename and title markers.

    /^\@setfilename\s+([^.]+)/ and $fn = $1, next;

    /^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;

    # Identify a man title but keep only the one we are interested in.

    /^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {

        if (exists $defs{$1}) {

            $fn = $1;

            $tl = postprocess($2);

        }

        next;

    };

    /^\@include\s+(.+)$/ and do {

        push @instack, $inf;

        $inf = gensym();

        # Try cwd and $ibase.

        open($inf, "<" . $1)

            or open($inf, "<" . $ibase . "/" . $1)

                or die "cannot open $1 or $ibase/$1: $!\n";

        next;

    };

    # Look for blocks surrounded by @c man begin SECTION ... @c man end.

    # This really oughta be @ifman ... @end ifman and the like, but such

    # would require rev'ing all other Texinfo translators.

    /^\@c\s+man\s+begin\s+([A-Za-z ]+)/ and $sect = $1, push (@sects_sequence, $sect), $output = 1, next;

    /^\@c\s+man\s+end/ and do {

        $sects{$sect} = "" unless exists $sects{$sect};

        $sects{$sect} .= postprocess($section);

        $section = "";

        $output = 0;

        next;

    };

    # handle variables

    /^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {

        $defs{$1} = $2;

        next;

    };

    /^\@clear\s+([a-zA-Z0-9_-]+)/ and do {

        delete $defs{$1};

        next;

    };

    next unless $output;

    # Discard comments.  (Can't do it above, because then we'd never see

    # @c man lines.)

    /^\@c\b/ and next;

    # End-block handler goes up here because it needs to operate even

    # if we are skipping.

    /^\@end\s+([a-z]+)/ and do {

        # Ignore @end foo, where foo is not an operation which may

        # cause us to skip, if we are presently skipping.

        my $ended = $1;

        next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex)$/;

        die "\@end $ended without \@$ended at line $.\n" unless defined $endw;

        die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;

        $endw = pop @endwstack;

        if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex)$/) {

            $skipping = pop @skstack;

            next;

        } elsif ($ended =~ /^(?:example|smallexample|display)$/) {

            $shift = "";

            $_ = "";        # need a paragraph break

        } elsif ($ended =~ /^(?:itemize|enumerate|[fv]?table)$/) {

            $_ = "\n=back\n";

            $ic = pop @icstack;

        } else {

            die "unknown command \@end $ended at line $.\n";

        }

    };

    # We must handle commands which can cause skipping even while we

    # are skipping, otherwise we will not process nested conditionals

    # correctly.

    /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {

        push @endwstack, $endw;

        push @skstack, $skipping;

        $endw = "ifset";

        $skipping = 1 unless exists $defs{$1};

        next;

    };

    /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {

        push @endwstack, $endw;

        push @skstack, $skipping;

        $endw = "ifclear";

        $skipping = 1 if exists $defs{$1};

        next;

    };

    /^\@(ignore|menu|iftex)\b/ and do {

        push @endwstack, $endw;

        push @skstack, $skipping;

        $endw = $1;

        $skipping = 1;

        next;

    };

    next if $skipping;

    # Character entities.  First the ones that can be replaced by raw text

    # or discarded outright:

    s/\@copyright\{\}/(c)/g;

    s/\@dots\{\}/.../g;

    s/\@enddots\{\}/..../g;

    s/\@([.!? ])/$1/g;

    s/\@[:-]//g;

    s/\@bullet(?:\{\})?/*/g;

    s/\@TeX\{\}/TeX/g;

    s/\@pounds\{\}/\#/g;

    s/\@minus(?:\{\})?/-/g;

    s/\\,/,/g;

    # Now the ones that have to be replaced by special escapes

    # (which will be turned back into text by unmunge())

    s/&/&/g;

    s/\@\{/{/g;

    s/\@\}/}/g;

    s/\@\@/&at;/g;

    # Inside a verbatim block, handle @var specially.

    if ($shift ne "") {

        s/\@var\{([^\}]*)\}/<$1>/g;

    }

    # POD doesn't interpret E<> inside a verbatim block.

    if ($shift eq "") {

        s/</&lt;/g;

        s/>/>/g;

    } else {

        s/</&LT;/g;

        s/>/>/g;

    }

    # Single line command handlers.

    /^\@(?:section|unnumbered|unnumberedsec|center)\s+(.+)$/

        and $_ = "\n=head2 $1\n";

    /^\@subsection\s+(.+)$/

        and $_ = "\n=head3 $1\n";

    # Block command handlers:

    /^\@itemize\s*(\@[a-z]+|\*|-)?/ and do {

        push @endwstack, $endw;

        push @icstack, $ic;

        $ic = $1 ? $1 : "*";

        $_ = "\n=over 4\n";

        $endw = "itemize";

    };

    /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {

        push @endwstack, $endw;

        push @icstack, $ic;

        if (defined $1) {

            $ic = $1 . ".";

        } else {

            $ic = "1.";

        }

        $_ = "\n=over 4\n";

        $endw = "enumerate";

    };

    /^\@([fv]?table)\s+(\@[a-z]+)/ and do {

        push @endwstack, $endw;

        push @icstack, $ic;

        $endw = $1;

        $ic = $2;

        $ic =~ s/\@(?:samp|strong|key|gcctabopt|option|env)/B/;

        $ic =~ s/\@(?:code|kbd)/C/;

        $ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;

        $ic =~ s/\@(?:file)/F/;

        $_ = "\n=over 4\n";

    };

    /^\@((?:small)?example|display)/ and do {

        push @endwstack, $endw;

        $endw = $1;

        $shift = "\t";

        $_ = "";        # need a paragraph break

    };

    /^\@itemx?\s*(.+)?$/ and do {

        if (defined $1) {

            # Entity escapes prevent munging by the <> processing below.

            $_ = "\n=item $ic\<$1\>\n";

        } else {

            $_ = "\n=item $ic\n";

            $ic =~ y/A-Ya-y/B-Zb-z/;

            $ic =~ s/(\d+)/$1 + 1/eg;

        }

    };

    $section .= $shift.$_."\n";

}

# End of current file.

close($inf);

$inf = pop @instack;

}

die "No filename or title\n" unless defined $fn && defined $tl;

$sects{NAME} = "$fn \- $tl\n";

$sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};

unshift @sects_sequence, "NAME";

for $sect (@sects_sequence) {

    if(exists $sects{$sect}) {

        $head = $sect;

        $head =~ s/SEEALSO/SEE ALSO/;

        print "=head1 $head\n\n";

        print scalar unmunge ($sects{$sect});

        print "\n";

    }

}

sub usage

{

    die "usage: $0 [-D toggle...] [infile [outfile]]\n";

}

sub postprocess

{

    local $_ = $_[0];

    # @value{foo} is replaced by whatever 'foo' is defined as.

    while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {

        if (! exists $defs{$2}) {

            print STDERR "Option $2 not defined\n";

            s/\Q$1\E//;

        } else {

            $value = $defs{$2};

            s/\Q$1\E/$value/;

        }

    }

    # Formatting commands.

    # Temporary escape for @r.

    s/\@r\{([^\}]*)\}/R<$1>/g;

    s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;

    s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;

    s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;

    s/\@sc\{([^\}]*)\}/\U$1/g;

    s/\@file\{([^\}]*)\}/F<$1>/g;

    s/\@w\{([^\}]*)\}/S<$1>/g;

    s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;

    # Cross references are thrown away, as are @noindent and @refill.

    # (@noindent is impossible in .pod, and @refill is unnecessary.)

    # @* is also impossible in .pod; we discard it and any newline that

    # follows it.  Similarly, our macro @gol must be discarded.

    s/\@anchor{(?:[^\}]*)\}//g;

    s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;

    s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;

    s/;\s+\@pxref\{(?:[^\}]*)\}//g;

    s/\@noindent\s*//g;

    s/\@refill//g;

    s/\@gol//g;

    s/\@\*\s*\n?//g;

    # @uref can take one, two, or three arguments, with different

    # semantics each time.  @url and @email are just like @uref with

    # one argument, for our purposes.

    s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;

    s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;

    s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;

    # Turn B<blah I<blah> blah> into B<blah> I<blah> B<blah> to

    # match Texinfo semantics of @emph inside @samp.  Also handle @r

    # inside bold.

    s/&LT;/</g;

    s/>/>/g;

    1 while s/B<((?:[^<>]|I<[^<>]*>)*)R<([^>]*)>/B<$1>${2}B</g;

    1 while (s/B<([^<>]*)I<([^>]+)>/B<$1>I<$2>B</g);

    1 while (s/I<([^<>]*)B<([^>]+)>/I<$1>B<$2>I</g);

    s/[BI]<>//g;

    s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;

    s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;

    # Extract footnotes.  This has to be done after all other

    # processing because otherwise the regexp will choke on formatting

    # inside @footnote.

    while (/\@footnote/g) {

        s/\@footnote\{([^\}]+)\}/[$fnno]/;

        add_footnote($1, $fnno);

        $fnno++;

    }

    return $_;

}

sub unmunge

{

    # Replace escaped symbols with their equivalents.

    local $_ = $_[0];

    s/&lt;/E<lt>/g;

    s/&gt;/E<gt>/g;

    s/{/\{/g;

    s/}/\}/g;

    s/&at;/\@/g;

    s/&/&/g;

    return $_;

}

sub add_footnote

{

    unless (exists $sects{FOOTNOTES}) {

        $sects{FOOTNOTES} = "\n=over 4\n\n";

    }

    $sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;

    $sects{FOOTNOTES} .= $_[0];

    $sects{FOOTNOTES} .= "\n\n";

}

# stolen from Symbol.pm

{

    my $genseq = 0;

    sub gensym

    {

        my $name = "GEN" . $genseq++;

        my $ref = \*{$name};

        delete $::{$name};

        return $ref;

    }

}