1#! /usr/bin/perl -w
2
3#   Copyright (C) 1999, 2000, 2001, 2003 Free Software Foundation, Inc.
4
5# This file is part of GCC.
6
7# GCC 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# GCC 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 GCC; 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
26$output = 0;
27$skipping = 0;
28%sects = ();
29$section = "";
30@icstack = ();
31@endwstack = ();
32@skstack = ();
33@instack = ();
34$shift = "";
35%defs = ();
36$fnno = 1;
37$inf = "";
38$ibase = "";
39
40while ($_ = shift) {
41    if (/^-D(.*)$/) {
42	if ($1 ne "") {
43	    $flag = $1;
44	} else {
45	    $flag = shift;
46	}
47	$value = "";
48	($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);
49	die "no flag specified for -D\n"
50	    unless $flag ne "";
51	die "flags may only contain letters, digits, hyphens, dashes and underscores\n"
52	    unless $flag =~ /^[a-zA-Z0-9_-]+$/;
53	$defs{$flag} = $value;
54    } elsif (/^-/) {
55	usage();
56    } else {
57	$in = $_, next unless defined $in;
58	$out = $_, next unless defined $out;
59	usage();
60    }
61}
62
63if (defined $in) {
64    $inf = gensym();
65    open($inf, "<$in") or die "opening \"$in\": $!\n";
66    $ibase = $1 if $in =~ m|^(.+)/[^/]+$|;
67} else {
68    $inf = \*STDIN;
69}
70
71if (defined $out) {
72    open(STDOUT, ">$out") or die "opening \"$out\": $!\n";
73}
74
75while(defined $inf) {
76while(<$inf>) {
77    # Certain commands are discarded without further processing.
78    /^\@(?:
79	 [a-z]+index		# @*index: useful only in complete manual
80	 |need			# @need: useful only in printed manual
81	 |(?:end\s+)?group	# @group .. @end group: ditto
82	 |page			# @page: ditto
83	 |node			# @node: useful only in .info file
84	 |(?:end\s+)?ifnottex   # @ifnottex .. @end ifnottex: use contents
85	)\b/x and next;
86
87    chomp;
88
89    # Look for filename and title markers.
90    /^\@setfilename\s+([^.]+)/ and $fn = $1, next;
91    /^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;
92
93    # Identify a man title but keep only the one we are interested in.
94    /^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {
95	if (exists $defs{$1}) {
96	    $fn = $1;
97	    $tl = postprocess($2);
98	}
99	next;
100    };
101
102    # Look for blocks surrounded by @c man begin SECTION ... @c man end.
103    # This really oughta be @ifman ... @end ifman and the like, but such
104    # would require rev'ing all other Texinfo translators.
105    /^\@c\s+man\s+begin\s+([A-Z]+)\s+([A-Za-z0-9-]+)/ and do {
106	$output = 1 if exists $defs{$2};
107        $sect = $1;
108	next;
109    };
110    /^\@c\s+man\s+begin\s+([A-Z]+)/ and $sect = $1, $output = 1, next;
111    /^\@c\s+man\s+end/ and do {
112	$sects{$sect} = "" unless exists $sects{$sect};
113	$sects{$sect} .= postprocess($section);
114	$section = "";
115	$output = 0;
116	next;
117    };
118
119    # handle variables
120    /^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {
121	$defs{$1} = $2;
122	next;
123    };
124    /^\@clear\s+([a-zA-Z0-9_-]+)/ and do {
125	delete $defs{$1};
126	next;
127    };
128
129    next unless $output;
130
131    # Discard comments.  (Can't do it above, because then we'd never see
132    # @c man lines.)
133    /^\@c\b/ and next;
134
135    # End-block handler goes up here because it needs to operate even
136    # if we are skipping.
137    /^\@end\s+([a-z]+)/ and do {
138	# Ignore @end foo, where foo is not an operation which may
139	# cause us to skip, if we are presently skipping.
140	my $ended = $1;
141	next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex|copying)$/;
142
143	die "\@end $ended without \@$ended at line $.\n" unless defined $endw;
144	die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;
145
146	$endw = pop @endwstack;
147
148	if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex)$/) {
149	    $skipping = pop @skstack;
150	    next;
151	} elsif ($ended =~ /^(?:example|smallexample|display)$/) {
152	    $shift = "";
153	    $_ = "";	# need a paragraph break
154	} elsif ($ended =~ /^(?:itemize|enumerate|[fv]?table)$/) {
155	    $_ = "\n=back\n";
156	    $ic = pop @icstack;
157	} else {
158	    die "unknown command \@end $ended at line $.\n";
159	}
160    };
161
162    # We must handle commands which can cause skipping even while we
163    # are skipping, otherwise we will not process nested conditionals
164    # correctly.
165    /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
166	push @endwstack, $endw;
167	push @skstack, $skipping;
168	$endw = "ifset";
169	$skipping = 1 unless exists $defs{$1};
170	next;
171    };
172
173    /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
174	push @endwstack, $endw;
175	push @skstack, $skipping;
176	$endw = "ifclear";
177	$skipping = 1 if exists $defs{$1};
178	next;
179    };
180
181    /^\@(ignore|menu|iftex|copying)\b/ and do {
182	push @endwstack, $endw;
183	push @skstack, $skipping;
184	$endw = $1;
185	$skipping = 1;
186	next;
187    };
188
189    next if $skipping;
190
191    # Character entities.  First the ones that can be replaced by raw text
192    # or discarded outright:
193    s/\@copyright\{\}/(c)/g;
194    s/\@dots\{\}/.../g;
195    s/\@enddots\{\}/..../g;
196    s/\@([.!? ])/$1/g;
197    s/\@[:-]//g;
198    s/\@bullet(?:\{\})?/*/g;
199    s/\@TeX\{\}/TeX/g;
200    s/\@pounds\{\}/\#/g;
201    s/\@minus(?:\{\})?/-/g;
202    s/\\,/,/g;
203
204    # Now the ones that have to be replaced by special escapes
205    # (which will be turned back into text by unmunge())
206    s/&/&amp;/g;
207    s/\@\{/&lbrace;/g;
208    s/\@\}/&rbrace;/g;
209    s/\@\@/&at;/g;
210
211    # Inside a verbatim block, handle @var specially.
212    if ($shift ne "") {
213	s/\@var\{([^\}]*)\}/<$1>/g;
214    }
215
216    # POD doesn't interpret E<> inside a verbatim block.
217    if ($shift eq "") {
218	s/</&lt;/g;
219	s/>/&gt;/g;
220    } else {
221	s/</&LT;/g;
222	s/>/&GT;/g;
223    }
224
225    # Single line command handlers.
226
227    /^\@include\s+(.+)$/ and do {
228	push @instack, $inf;
229	$inf = gensym();
230	$file = postprocess($1);
231
232	# Try cwd and $ibase.
233	open($inf, "<" . $file)
234	    or open($inf, "<" . $ibase . "/" . $file)
235		or die "cannot open $file or $ibase/$file: $!\n";
236	next;
237    };
238
239    /^\@(?:section|unnumbered|unnumberedsec|center)\s+(.+)$/
240	and $_ = "\n=head2 $1\n";
241    /^\@subsection\s+(.+)$/
242	and $_ = "\n=head3 $1\n";
243
244    # Block command handlers:
245    /^\@itemize(?:\s+(\@[a-z]+|\*|-))?/ and do {
246	push @endwstack, $endw;
247	push @icstack, $ic;
248	if (defined $1) {
249	    $ic = $1;
250	} else {
251	    $ic = '@bullet';
252	}
253	$_ = "\n=over 4\n";
254	$endw = "itemize";
255    };
256
257    /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
258	push @endwstack, $endw;
259	push @icstack, $ic;
260	if (defined $1) {
261	    $ic = $1 . ".";
262	} else {
263	    $ic = "1.";
264	}
265	$_ = "\n=over 4\n";
266	$endw = "enumerate";
267    };
268
269    /^\@([fv]?table)\s+(\@[a-z]+)/ and do {
270	push @endwstack, $endw;
271	push @icstack, $ic;
272	$endw = $1;
273	$ic = $2;
274	$ic =~ s/\@(?:samp|strong|key|gcctabopt|env)/B/;
275	$ic =~ s/\@(?:code|kbd)/C/;
276	$ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
277	$ic =~ s/\@(?:file)/F/;
278	$_ = "\n=over 4\n";
279    };
280
281    /^\@((?:small)?example|display)/ and do {
282	push @endwstack, $endw;
283	$endw = $1;
284	$shift = "\t";
285	$_ = "";	# need a paragraph break
286    };
287
288    /^\@itemx?\s*(.+)?$/ and do {
289	if (defined $1) {
290	    # Entity escapes prevent munging by the <> processing below.
291	    $_ = "\n=item $ic\&LT;$1\&GT;\n";
292	} else {
293	    $_ = "\n=item $ic\n";
294	    $ic =~ y/A-Ya-y/B-Zb-z/;
295	    $ic =~ s/(\d+)/$1 + 1/eg;
296	}
297    };
298
299    $section .= $shift.$_."\n";
300}
301# End of current file.
302close($inf);
303$inf = pop @instack;
304}
305
306die "No filename or title\n" unless defined $fn && defined $tl;
307
308$sects{NAME} = "$fn \- $tl\n";
309$sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};
310
311for $sect (qw(NAME SYNOPSIS DESCRIPTION OPTIONS ENVIRONMENT FILES
312	      BUGS NOTES FOOTNOTES SEEALSO AUTHOR COPYRIGHT)) {
313    if(exists $sects{$sect}) {
314	$head = $sect;
315	$head =~ s/SEEALSO/SEE ALSO/;
316	print "=head1 $head\n\n";
317	print scalar unmunge ($sects{$sect});
318	print "\n";
319    }
320}
321
322sub usage
323{
324    die "usage: $0 [-D toggle...] [infile [outfile]]\n";
325}
326
327sub postprocess
328{
329    local $_ = $_[0];
330
331    # @value{foo} is replaced by whatever 'foo' is defined as.
332    while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
333	if (! exists $defs{$2}) {
334	    print STDERR "Option $2 not defined\n";
335	    s/\Q$1\E//;
336	} else {
337	    $value = $defs{$2};
338	    s/\Q$1\E/$value/;
339	}
340    }
341
342    # Formatting commands.
343    # Temporary escape for @r.
344    s/\@r\{([^\}]*)\}/R<$1>/g;
345    s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
346    s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
347    s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
348    s/\@sc\{([^\}]*)\}/\U$1/g;
349    s/\@file\{([^\}]*)\}/F<$1>/g;
350    s/\@w\{([^\}]*)\}/S<$1>/g;
351    s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
352
353    # keep references of the form @ref{...}, print them bold
354    s/\@(?:ref)\{([^\}]*)\}/B<$1>/g;
355
356    # Change double single quotes to double quotes.
357    s/''/"/g;
358    s/``/"/g;
359
360    # Cross references are thrown away, as are @noindent and @refill.
361    # (@noindent is impossible in .pod, and @refill is unnecessary.)
362    # @* is also impossible in .pod; we discard it and any newline that
363    # follows it.  Similarly, our macro @gol must be discarded.
364
365    s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
366    s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
367    s/;\s+\@pxref\{(?:[^\}]*)\}//g;
368    s/\@noindent\s*//g;
369    s/\@refill//g;
370    s/\@gol//g;
371    s/\@\*\s*\n?//g;
372
373    # @uref can take one, two, or three arguments, with different
374    # semantics each time.  @url and @email are just like @uref with
375    # one argument, for our purposes.
376    s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;
377    s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
378    s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
379
380    # Un-escape <> at this point.
381    s/&LT;/</g;
382    s/&GT;/>/g;
383
384    # Now un-nest all B<>, I<>, R<>.  Theoretically we could have
385    # indefinitely deep nesting; in practice, one level suffices.
386    1 while s/([BIR])<([^<>]*)([BIR])<([^<>]*)>/$1<$2>$3<$4>$1</g;
387
388    # Replace R<...> with bare ...; eliminate empty markup, B<>;
389    # shift white space at the ends of [BI]<...> expressions outside
390    # the expression.
391    s/R<([^<>]*)>/$1/g;
392    s/[BI]<>//g;
393    s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
394    s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
395
396    # Extract footnotes.  This has to be done after all other
397    # processing because otherwise the regexp will choke on formatting
398    # inside @footnote.
399    while (/\@footnote/g) {
400	s/\@footnote\{([^\}]+)\}/[$fnno]/;
401	add_footnote($1, $fnno);
402	$fnno++;
403    }
404
405    return $_;
406}
407
408sub unmunge
409{
410    # Replace escaped symbols with their equivalents.
411    local $_ = $_[0];
412
413    s/&lt;/E<lt>/g;
414    s/&gt;/E<gt>/g;
415    s/&lbrace;/\{/g;
416    s/&rbrace;/\}/g;
417    s/&at;/\@/g;
418    s/&amp;/&/g;
419    return $_;
420}
421
422sub add_footnote
423{
424    unless (exists $sects{FOOTNOTES}) {
425	$sects{FOOTNOTES} = "\n=over 4\n\n";
426    }
427
428    $sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
429    $sects{FOOTNOTES} .= $_[0];
430    $sects{FOOTNOTES} .= "\n\n";
431}
432
433# stolen from Symbol.pm
434{
435    my $genseq = 0;
436    sub gensym
437    {
438	my $name = "GEN" . $genseq++;
439	my $ref = \*{$name};
440	delete $::{$name};
441	return $ref;
442    }
443}
444