1#!/usr/bin/env perl
2
3#   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
4
5# This file is part of GNU CC.
6
7# GNU CC is free software; you can redistribute it and/or modify
8# it under the terms of the GNU General Public License as published by
9# the Free Software Foundation; either version 2, or (at your option)
10# any later version.
11
12# GNU CC is distributed in the hope that it will be useful,
13# but WITHOUT ANY WARRANTY; without even the implied warranty of
14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15# GNU General Public License for more details.
16
17# You should have received a copy of the GNU General Public License
18# along with GNU CC; see the file COPYING.  If not, write to
19# the Free Software Foundation, 51 Franklin Street, Fifth Floor,
20# Boston, MA 02110-1301 USA
21
22# This does trivial (and I mean _trivial_) conversion of Texinfo
23# markup to Perl POD format.  It's intended to be used to extract
24# something suitable for a manpage from a Texinfo document.
25
26use warnings;
27
28$output = 0;
29$skipping = 0;
30%chapters = ();
31@chapters_sequence = ();
32$chapter = "";
33@icstack = ();
34@endwstack = ();
35@skstack = ();
36@instack = ();
37$shift = "";
38%defs = ();
39$fnno = 1;
40$inf = "";
41@ibase = ();
42
43while ($_ = shift) {
44    if (/^-D(.*)$/) {
45        if ($1 ne "") {
46            $flag = $1;
47        } else {
48            $flag = shift;
49        }
50        $value = "";
51        ($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);
52        die "no flag specified for -D\n"
53            unless $flag ne "";
54        die "flags may only contain letters, digits, hyphens, dashes and underscores\n"
55            unless $flag =~ /^[a-zA-Z0-9_-]+$/;
56        $defs{$flag} = $value;
57    } elsif (/^-I(.*)$/) {
58        push @ibase, $1 ne "" ? $1 : shift;
59    } elsif (/^-/) {
60        usage();
61    } else {
62        $in = $_, next unless defined $in;
63        $out = $_, next unless defined $out;
64        usage();
65    }
66}
67
68push @ibase, ".";
69
70if (defined $in) {
71    $inf = gensym();
72    open($inf, "<$in") or die "opening \"$in\": $!\n";
73    push @ibase, $1 if $in =~ m|^(.+)/[^/]+$|;
74} else {
75    $inf = \*STDIN;
76}
77
78if (defined $out) {
79    open(STDOUT, ">$out") or die "opening \"$out\": $!\n";
80}
81
82while(defined $inf) {
83INF: while(<$inf>) {
84    # Certain commands are discarded without further processing.
85    /^\@(?:
86         [a-z]+index            # @*index: useful only in complete manual
87         |need                  # @need: useful only in printed manual
88         |(?:end\s+)?group      # @group .. @end group: ditto
89         |page                  # @page: ditto
90         |node                  # @node: useful only in .info file
91         |(?:end\s+)?ifnottex   # @ifnottex .. @end ifnottex: use contents
92        )\b/x and next;
93
94    chomp;
95
96    # Look for filename and title markers.
97    /^\@setfilename\s+([^.]+)/ and $fn = $1, next;
98    /^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;
99
100    # Identify a man title but keep only the one we are interested in.
101    /^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {
102        if (exists $defs{$1}) {
103            $fn = $1;
104            $tl = postprocess($2);
105        }
106        next;
107    };
108
109    /^\@include\s+(.+)$/ and do {
110        push @instack, $inf;
111        $inf = gensym();
112
113        for (@ibase) {
114            open($inf, "<" . $_ . "/" . $1) and next INF;
115        }
116        die "cannot open $1: $!\n";
117    };
118
119    /^\@chapter\s+([A-Za-z ]+)/ and do {
120        # close old chapter
121        $chapters{$chapter_name} .= postprocess($chapter) if ($chapter_name);
122
123        # start new chapter
124        $chapter_name = $1, push (@chapters_sequence, $chapter_name) unless $skipping;
125        $chapters{$chapter_name} = "" unless exists $chapters{$chapter_name};
126        $chapter = "";
127        $output = 1;
128        next;
129    };
130
131    /^\@bye/ and do {
132        # close old chapter
133        $chapters{$chapter_name} .= postprocess($chapter) if ($chapter_name);
134        last INF;
135    };
136
137    # handle variables
138    /^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {
139        $defs{$1} = $2;
140        next;
141    };
142    /^\@clear\s+([a-zA-Z0-9_-]+)/ and do {
143        delete $defs{$1};
144        next;
145    };
146
147    next unless $output;
148
149    # Discard comments.  (Can't do it above, because then we'd never see
150    # @c man lines.)
151    /^\@c\b/ and next;
152
153    # End-block handler goes up here because it needs to operate even
154    # if we are skipping.
155    /^\@end\s+([a-z]+)/ and do {
156        # Ignore @end foo, where foo is not an operation which may
157        # cause us to skip, if we are presently skipping.
158        my $ended = $1;
159        next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex|ifhtml|ifnothtml)$/;
160
161        die "\@end $ended without \@$ended at line $.\n" unless defined $endw;
162        die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;
163
164        $endw = pop @endwstack;
165
166        if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex|ifhtml|ifnothtml)$/) {
167            $skipping = pop @skstack;
168            next;
169        } elsif ($ended =~ /^(?:example|smallexample|display)$/) {
170            $shift = "";
171            $_ = "";        # need a paragraph break
172        } elsif ($ended =~ /^(?:itemize|enumerate|(?:multi|[fv])?table)$/) {
173            $_ = "\n=back\n";
174            $ic = pop @icstack;
175        } else {
176            die "unknown command \@end $ended at line $.\n";
177        }
178    };
179
180    # We must handle commands which can cause skipping even while we
181    # are skipping, otherwise we will not process nested conditionals
182    # correctly.
183    /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
184        push @endwstack, $endw;
185        push @skstack, $skipping;
186        $endw = "ifset";
187        $skipping = 1 unless exists $defs{$1};
188        next;
189    };
190
191    /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
192        push @endwstack, $endw;
193        push @skstack, $skipping;
194        $endw = "ifclear";
195        $skipping = 1 if exists $defs{$1};
196        next;
197    };
198
199    /^\@(ignore|menu|iftex|ifhtml|ifnothtml)\b/ and do {
200        push @endwstack, $endw;
201        push @skstack, $skipping;
202        $endw = $1;
203        $skipping = $endw !~ /ifnothtml/;
204        next;
205    };
206
207    next if $skipping;
208
209    # Character entities.  First the ones that can be replaced by raw text
210    # or discarded outright:
211    s/\@copyright\{\}/(c)/g;
212    s/\@dots\{\}/.../g;
213    s/\@enddots\{\}/..../g;
214    s/\@([.!? ])/$1/g;
215    s/\@[:-]//g;
216    s/\@bullet(?:\{\})?/*/g;
217    s/\@TeX\{\}/TeX/g;
218    s/\@pounds\{\}/\#/g;
219    s/\@minus(?:\{\})?/-/g;
220
221    # Now the ones that have to be replaced by special escapes
222    # (which will be turned back into text by unmunge())
223    s/&/&amp;/g;
224    s/\@\{/&lbrace;/g;
225    s/\@\}/&rbrace;/g;
226    s/\@\@/&at;/g;
227
228    # Inside a verbatim block, handle @var specially.
229    if ($shift ne "") {
230        s/\@var\{([^\}]*)\}/<$1>/g;
231    }
232
233    # POD doesn't interpret E<> inside a verbatim block.
234    if ($shift eq "") {
235        s/</&lt;/g;
236        s/>/&gt;/g;
237    } else {
238        s/</&LT;/g;
239        s/>/&GT;/g;
240    }
241
242    # Single line command handlers.
243
244    /^\@(?:section|unnumbered|unnumberedsec|center|heading)\s+(.+)$/
245        and $_ = "\n=head2 $1\n";
246    /^\@(?:subsection|subheading)\s+(.+)$/
247        and $_ = "\n=head3 $1\n";
248    /^\@(?:subsubsection|subsubheading)\s+(.+)$/
249        and $_ = "\n=head4 $1\n";
250
251    # Block command handlers:
252    /^\@itemize\s*(\@[a-z]+|\*|-)?/ and do {
253        push @endwstack, $endw;
254        push @icstack, $ic;
255        $ic = $1 ? $1 : "*";
256        $_ = "\n=over 4\n";
257        $endw = "itemize";
258    };
259
260    /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
261        push @endwstack, $endw;
262        push @icstack, $ic;
263        if (defined $1) {
264            $ic = $1 . ".";
265        } else {
266            $ic = "1.";
267        }
268        $_ = "\n=over 4\n";
269        $endw = "enumerate";
270    };
271
272    /^\@((?:multi|[fv])?table)\s+(\@[a-z]+)/ and do {
273        push @endwstack, $endw;
274        push @icstack, $ic;
275        $endw = $1;
276        $ic = $2;
277        $ic =~ s/\@(?:samp|strong|key|gcctabopt|option|env|command)/B/;
278        $ic =~ s/\@(?:code|kbd)/C/;
279        $ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
280        $ic =~ s/\@(?:file)/F/;
281        $ic =~ s/\@(?:columnfractions)//;
282        $_ = "\n=over 4\n";
283    };
284
285    /^\@(multitable)\s+{.*/ and do {
286        push @endwstack, $endw;
287        push @icstack, $ic;
288        $endw = $1;
289        $ic = "";
290        $_ = "\n=over 4\n";
291    };
292
293    /^\@((?:small)?example|display)/ and do {
294        push @endwstack, $endw;
295        $endw = $1;
296        $shift = "\t";
297        $_ = "";        # need a paragraph break
298    };
299
300    /^\@item\s+(.*\S)\s*$/ and $endw eq "multitable" and do {
301        my $columns = $1;
302        $columns =~ s/\@tab/ : /;
303
304        $_ = "\n=item B&LT;". $columns ."&GT;\n";
305    };
306
307    /^\@tab\s+(.*\S)\s*$/ and $endw eq "multitable" and do {
308        my $columns = $1;
309        $columns =~ s/\@tab//;
310
311        $_ = $columns;
312        $chapter =~ s/$//;
313    };
314
315    /^\@itemx?\s*(.+)?$/ and do {
316        if (defined $1) {
317            # Entity escapes prevent munging by the <> processing below.
318            $_ = "\n=item $ic\&LT;$1\&GT;\n";
319        } else {
320            $_ = "\n=item $ic\n";
321            $ic =~ y/A-Ya-y/B-Zb-z/;
322            $ic =~ s/(\d+)/$1 + 1/eg;
323        }
324    };
325
326    $chapter .= $shift.$_."\n";
327}
328# End of current file.
329close($inf);
330$inf = pop @instack;
331}
332
333die "No filename or title\n" unless defined $fn && defined $tl;
334
335# always use utf8
336print "=encoding utf8\n\n";
337
338$chapters{NAME} = "$fn \- $tl\n";
339$chapters{FOOTNOTES} .= "=back\n" if exists $chapters{FOOTNOTES};
340
341unshift @chapters_sequence, "NAME";
342for $chapter (@chapters_sequence) {
343    if (exists $chapters{$chapter}) {
344        $head = uc($chapter);
345        print "=head1 $head\n\n";
346        print scalar unmunge ($chapters{$chapter});
347        print "\n";
348    }
349}
350
351sub usage
352{
353    die "usage: $0 [-D toggle...] [infile [outfile]]\n";
354}
355
356sub postprocess
357{
358    local $_ = $_[0];
359
360    # @value{foo} is replaced by whatever 'foo' is defined as.
361    while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
362        if (! exists $defs{$2}) {
363            print STDERR "Option $2 not defined\n";
364            s/\Q$1\E//;
365        } else {
366            $value = $defs{$2};
367            s/\Q$1\E/$value/;
368        }
369    }
370
371    # Formatting commands.
372    # Temporary escape for @r.
373    s/\@r\{([^\}]*)\}/R<$1>/g;
374    s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
375    s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
376    s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
377    s/\@sc\{([^\}]*)\}/\U$1/g;
378    s/\@file\{([^\}]*)\}/F<$1>/g;
379    s/\@w\{([^\}]*)\}/S<$1>/g;
380    s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
381
382    # Cross references are thrown away, as are @noindent and @refill.
383    # (@noindent is impossible in .pod, and @refill is unnecessary.)
384    # @* is also impossible in .pod; we discard it and any newline that
385    # follows it.  Similarly, our macro @gol must be discarded.
386
387    s/\@anchor\{(?:[^\}]*)\}//g;
388    s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
389    s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
390    s/;\s+\@pxref\{(?:[^\}]*)\}//g;
391    s/\@ref\{(?:[^,\}]*,)(?:[^,\}]*,)([^,\}]*).*\}/B<$1>/g;
392    s/\@ref\{([^\}]*)\}/B<$1>/g;
393    s/\@noindent\s*//g;
394    s/\@refill//g;
395    s/\@gol//g;
396    s/\@\*\s*\n?//g;
397
398    # @uref can take one, two, or three arguments, with different
399    # semantics each time.  @url and @email are just like @uref with
400    # one argument, for our purposes.
401    s/\@(?:uref|url|email)\{([^\},]*),?[^\}]*\}/&lt;B<$1>&gt;/g;
402    s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
403    s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
404
405    # Turn B<blah I<blah> blah> into B<blah> I<blah> B<blah> to
406    # match Texinfo semantics of @emph inside @samp.  Also handle @r
407    # inside bold.
408    s/&LT;/</g;
409    s/&GT;/>/g;
410    1 while s/B<((?:[^<>]|I<[^<>]*>)*)R<([^>]*)>/B<$1>${2}B</g;
411    1 while (s/B<([^<>]*)I<([^>]+)>/B<$1>I<$2>B</g);
412    1 while (s/I<([^<>]*)B<([^>]+)>/I<$1>B<$2>I</g);
413    s/[BI]<>//g;
414    s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
415    s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
416
417    # Extract footnotes.  This has to be done after all other
418    # processing because otherwise the regexp will choke on formatting
419    # inside @footnote.
420    while (/\@footnote/g) {
421        s/\@footnote\{([^\}]+)\}/[$fnno]/;
422        add_footnote($1, $fnno);
423        $fnno++;
424    }
425
426    return $_;
427}
428
429sub unmunge
430{
431    # Replace escaped symbols with their equivalents.
432    local $_ = $_[0];
433
434    s/&lt;/E<lt>/g;
435    s/&gt;/E<gt>/g;
436    s/&lbrace;/\{/g;
437    s/&rbrace;/\}/g;
438    s/&at;/\@/g;
439    s/&amp;/&/g;
440    return $_;
441}
442
443sub add_footnote
444{
445    unless (exists $chapters{FOOTNOTES}) {
446        $chapters{FOOTNOTES} = "\n=over 4\n\n";
447    }
448
449    $chapters{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
450    $chapters{FOOTNOTES} .= $_[0];
451    $chapters{FOOTNOTES} .= "\n\n";
452}
453
454# stolen from Symbol.pm
455{
456    my $genseq = 0;
457    sub gensym
458    {
459        my $name = "GEN" . $genseq++;
460        my $ref = \*{$name};
461        delete $::{$name};
462        return $ref;
463    }
464}
465