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$ibase = "";
39@ipath = ();
40
41while ($_ = shift) {
42    if (/^-D(.*)$/) {
43	if ($1 ne "") {
44	    $flag = $1;
45	} else {
46	    $flag = shift;
47	}
48	$value = "";
49	($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);
50	die "no flag specified for -D\n"
51	    unless $flag ne "";
52	die "flags may only contain letters, digits, hyphens, dashes and underscores\n"
53	    unless $flag =~ /^[a-zA-Z0-9_-]+$/;
54	$defs{$flag} = $value;
55    } elsif (/^-I(.*)$/) {
56	if ($1 ne "") {
57	    $flag = $1;
58	} else {
59	    $flag = shift;
60	}
61        push (@ipath, $flag);
62    } elsif (/^-/) {
63	usage();
64    } else {
65	$in = $_, next unless defined $in;
66	$out = $_, next unless defined $out;
67	usage();
68    }
69}
70
71if (defined $in) {
72    $inf = gensym();
73    open($inf, "<$in") or die "opening \"$in\": $!\n";
74    $ibase = $1 if $in =~ m|^(.+)/[^/]+$|;
75} else {
76    $inf = \*STDIN;
77}
78
79if (defined $out) {
80    open(STDOUT, ">$out") or die "opening \"$out\": $!\n";
81}
82
83while(defined $inf) {
84while(<$inf>) {
85    # Certain commands are discarded without further processing.
86    /^\@(?:
87	 [a-z]+index		# @*index: useful only in complete manual
88	 |need			# @need: useful only in printed manual
89	 |(?:end\s+)?group	# @group .. @end group: ditto
90	 |page			# @page: ditto
91	 |node			# @node: useful only in .info file
92	 |(?:end\s+)?ifnottex   # @ifnottex .. @end ifnottex: use contents
93	)\b/x and next;
94
95    chomp;
96
97    # Look for filename and title markers.
98    /^\@setfilename\s+([^.]+)/ and $fn = $1, next;
99    /^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;
100
101    # Identify a man title but keep only the one we are interested in.
102    /^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {
103	if (exists $defs{$1}) {
104	    $fn = $1;
105	    $tl = postprocess($2);
106	}
107	next;
108    };
109
110    # Look for blocks surrounded by @c man begin SECTION ... @c man end.
111    # This really oughta be @ifman ... @end ifman and the like, but such
112    # would require rev'ing all other Texinfo translators.
113    /^\@c\s+man\s+begin\s+([A-Z]+)\s+([A-Za-z0-9-]+)/ and do {
114	$output = 1 if exists $defs{$2};
115        $sect = $1;
116	next;
117    };
118    /^\@c\s+man\s+begin\s+([A-Z]+)/ and $sect = $1, $output = 1, next;
119    /^\@c\s+man\s+end/ and do {
120	$sects{$sect} = "" unless exists $sects{$sect};
121	$sects{$sect} .= postprocess($section);
122	$section = "";
123	$output = 0;
124	next;
125    };
126
127    # handle variables
128    /^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {
129	$defs{$1} = $2;
130	next;
131    };
132    /^\@clear\s+([a-zA-Z0-9_-]+)/ and do {
133	delete $defs{$1};
134	next;
135    };
136
137    next unless $output;
138
139    # Discard comments.  (Can't do it above, because then we'd never see
140    # @c man lines.)
141    /^\@c\b/ and next;
142
143    # End-block handler goes up here because it needs to operate even
144    # if we are skipping.
145    /^\@end\s+([a-z]+)/ and do {
146	# Ignore @end foo, where foo is not an operation which may
147	# cause us to skip, if we are presently skipping.
148	my $ended = $1;
149	next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex|copying)$/;
150
151	die "\@end $ended without \@$ended at line $.\n" unless defined $endw;
152	die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;
153
154	$endw = pop @endwstack;
155
156	if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex)$/) {
157	    $skipping = pop @skstack;
158	    next;
159	} elsif ($ended =~ /^(?:example|smallexample|display)$/) {
160	    $shift = "";
161	    $_ = "";	# need a paragraph break
162	} elsif ($ended =~ /^(?:itemize|enumerate|[fv]?table)$/) {
163	    $_ = "\n=back\n";
164	    $ic = pop @icstack;
165	} elsif ($ended eq "multitable") {
166	    $_ = "\n=back\n";
167	} else {
168	    die "unknown command \@end $ended at line $.\n";
169	}
170    };
171
172    # We must handle commands which can cause skipping even while we
173    # are skipping, otherwise we will not process nested conditionals
174    # correctly.
175    /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
176	push @endwstack, $endw;
177	push @skstack, $skipping;
178	$endw = "ifset";
179	$skipping = 1 unless exists $defs{$1};
180	next;
181    };
182
183    /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
184	push @endwstack, $endw;
185	push @skstack, $skipping;
186	$endw = "ifclear";
187	$skipping = 1 if exists $defs{$1};
188	next;
189    };
190
191    /^\@(ignore|menu|iftex|copying)\b/ and do {
192	push @endwstack, $endw;
193	push @skstack, $skipping;
194	$endw = $1;
195	$skipping = 1;
196	next;
197    };
198
199    next if $skipping;
200
201    # Character entities.  First the ones that can be replaced by raw text
202    # or discarded outright:
203    s/\@copyright\{\}/(c)/g;
204    s/\@dots\{\}/.../g;
205    s/\@enddots\{\}/..../g;
206    s/\@([.!? ])/$1/g;
207    s/\@[:-]//g;
208    s/\@bullet(?:\{\})?/*/g;
209    s/\@TeX\{\}/TeX/g;
210    s/\@pounds\{\}/\#/g;
211    s/\@minus(?:\{\})?/-/g;
212    s/\\,/,/g;
213
214    # Now the ones that have to be replaced by special escapes
215    # (which will be turned back into text by unmunge())
216    s/&/&amp;/g;
217    s/\@\{/&lbrace;/g;
218    s/\@\}/&rbrace;/g;
219    s/\@\@/&at;/g;
220
221    # Inside a verbatim block, handle @var specially.
222    if ($shift ne "") {
223	s/\@var\{([^\}]*)\}/<$1>/g;
224    }
225
226    # POD doesn't interpret E<> inside a verbatim block.
227    if ($shift eq "") {
228	s/</&lt;/g;
229	s/>/&gt;/g;
230    } else {
231	s/</&LT;/g;
232	s/>/&GT;/g;
233    }
234
235    # Single line command handlers.
236
237    /^\@include\s+(.+)$/ and do {
238	push @instack, $inf;
239	$inf = gensym();
240	$file = postprocess($1);
241
242	# Try cwd and $ibase, then explicit -I paths.
243	$done = 0;
244	foreach $path ("", $ibase, @ipath) {
245	    $mypath = $file;
246	    $mypath = $path . "/" . $mypath if ($path ne "");
247	    open($inf, "<" . $mypath) and ($done = 1, last);
248	}
249	die "cannot find $file" if !$done;
250	next;
251    };
252
253    /^\@(?:section|unnumbered|unnumberedsec|center)\s+(.+)$/
254	and $_ = "\n=head2 $1\n";
255    /^\@subsection\s+(.+)$/
256	and $_ = "\n=head3 $1\n";
257    /^\@subsubsection\s+(.+)$/
258	and $_ = "\n=head4 $1\n";
259
260    # Block command handlers:
261    /^\@itemize(?:\s+(\@[a-z]+|\*|-))?/ and do {
262	push @endwstack, $endw;
263	push @icstack, $ic;
264	if (defined $1) {
265	    $ic = $1;
266	} else {
267	    $ic = '*';
268	}
269	$_ = "\n=over 4\n";
270	$endw = "itemize";
271    };
272
273    /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
274	push @endwstack, $endw;
275	push @icstack, $ic;
276	if (defined $1) {
277	    $ic = $1 . ".";
278	} else {
279	    $ic = "1.";
280	}
281	$_ = "\n=over 4\n";
282	$endw = "enumerate";
283    };
284
285    /^\@multitable\s.*/ and do {
286	push @endwstack, $endw;
287	$endw = "multitable";
288	$_ = "\n=over 4\n";
289    };
290
291    /^\@([fv]?table)\s+(\@[a-z]+)/ and do {
292	push @endwstack, $endw;
293	push @icstack, $ic;
294	$endw = $1;
295	$ic = $2;
296	$ic =~ s/\@(?:samp|strong|key|gcctabopt|env)/B/;
297	$ic =~ s/\@(?:code|kbd)/C/;
298	$ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
299	$ic =~ s/\@(?:file)/F/;
300	$_ = "\n=over 4\n";
301    };
302
303    /^\@((?:small)?example|display)/ and do {
304	push @endwstack, $endw;
305	$endw = $1;
306	$shift = "\t";
307	$_ = "";	# need a paragraph break
308    };
309
310    /^\@item\s+(.*\S)\s*$/ and $endw eq "multitable" and do {
311	@columns = ();
312	for $column (split (/\s*\@tab\s*/, $1)) {
313	    # @strong{...} is used a @headitem work-alike
314	    $column =~ s/^\@strong{(.*)}$/$1/;
315	    push @columns, $column;
316	}
317	$_ = "\n=item ".join (" : ", @columns)."\n";
318    };
319
320    /^\@itemx?\s*(.+)?$/ and do {
321	if (defined $1) {
322	    # Entity escapes prevent munging by the <> processing below.
323	    $_ = "\n=item $ic\&LT;$1\&GT;\n";
324	} else {
325	    $_ = "\n=item $ic\n";
326	    $ic =~ y/A-Ya-y/B-Zb-z/;
327	    $ic =~ s/(\d+)/$1 + 1/eg;
328	}
329    };
330
331    $section .= $shift.$_."\n";
332}
333# End of current file.
334close($inf);
335$inf = pop @instack;
336}
337
338die "No filename or title\n" unless defined $fn && defined $tl;
339
340$sects{NAME} = "$fn \- $tl\n";
341$sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};
342
343for $sect (qw(NAME SYNOPSIS DESCRIPTION OPTIONS ENVIRONMENT FILES
344	      BUGS NOTES FOOTNOTES SEEALSO AUTHOR COPYRIGHT)) {
345    if(exists $sects{$sect}) {
346	$head = $sect;
347	$head =~ s/SEEALSO/SEE ALSO/;
348	print "=head1 $head\n\n";
349	print scalar unmunge ($sects{$sect});
350	print "\n";
351    }
352}
353
354sub usage
355{
356    die "usage: $0 [-D toggle...] [infile [outfile]]\n";
357}
358
359sub postprocess
360{
361    local $_ = $_[0];
362
363    # @value{foo} is replaced by whatever 'foo' is defined as.
364    while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
365	if (! exists $defs{$2}) {
366	    print STDERR "Option $2 not defined\n";
367	    s/\Q$1\E//;
368	} else {
369	    $value = $defs{$2};
370	    s/\Q$1\E/$value/;
371	}
372    }
373
374    # Formatting commands.
375    # Temporary escape for @r.
376    s/\@r\{([^\}]*)\}/R<$1>/g;
377    s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
378    s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
379    s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
380    s/\@sc\{([^\}]*)\}/\U$1/g;
381    s/\@file\{([^\}]*)\}/F<$1>/g;
382    s/\@w\{([^\}]*)\}/S<$1>/g;
383    s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
384
385    # keep references of the form @ref{...}, print them bold
386    s/\@(?:ref)\{([^\}]*)\}/B<$1>/g;
387
388    # Change double single quotes to double quotes.
389    s/''/"/g;
390    s/``/"/g;
391
392    # Cross references are thrown away, as are @noindent and @refill.
393    # (@noindent is impossible in .pod, and @refill is unnecessary.)
394    # @* is also impossible in .pod; we discard it and any newline that
395    # follows it.  Similarly, our macro @gol must be discarded.
396
397    s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
398    s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
399    s/;\s+\@pxref\{(?:[^\}]*)\}//g;
400    s/\@noindent\s*//g;
401    s/\@refill//g;
402    s/\@gol//g;
403    s/\@\*\s*\n?//g;
404
405    # Anchors are thrown away
406    s/\@anchor\{(?:[^\}]*)\}//g;
407
408    # @uref can take one, two, or three arguments, with different
409    # semantics each time.  @url and @email are just like @uref with
410    # one argument, for our purposes.
411    s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;
412    s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
413    s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
414
415    # Un-escape <> at this point.
416    s/&LT;/</g;
417    s/&GT;/>/g;
418
419    # Now un-nest all B<>, I<>, R<>.  Theoretically we could have
420    # indefinitely deep nesting; in practice, one level suffices.
421    1 while s/([BIR])<([^<>]*)([BIR])<([^<>]*)>/$1<$2>$3<$4>$1</g;
422
423    # Replace R<...> with bare ...; eliminate empty markup, B<>;
424    # shift white space at the ends of [BI]<...> expressions outside
425    # the expression.
426    s/R<([^<>]*)>/$1/g;
427    s/[BI]<>//g;
428    s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
429    s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
430
431    # Extract footnotes.  This has to be done after all other
432    # processing because otherwise the regexp will choke on formatting
433    # inside @footnote.
434    while (/\@footnote/g) {
435	s/\@footnote\{([^\}]+)\}/[$fnno]/;
436	add_footnote($1, $fnno);
437	$fnno++;
438    }
439
440    return $_;
441}
442
443sub unmunge
444{
445    # Replace escaped symbols with their equivalents.
446    local $_ = $_[0];
447
448    s/&lt;/E<lt>/g;
449    s/&gt;/E<gt>/g;
450    s/&lbrace;/\{/g;
451    s/&rbrace;/\}/g;
452    s/&at;/\@/g;
453    s/&amp;/&/g;
454    return $_;
455}
456
457sub add_footnote
458{
459    unless (exists $sects{FOOTNOTES}) {
460	$sects{FOOTNOTES} = "\n=over 4\n\n";
461    }
462
463    $sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
464    $sects{FOOTNOTES} .= $_[0];
465    $sects{FOOTNOTES} .= "\n\n";
466}
467
468# stolen from Symbol.pm
469{
470    my $genseq = 0;
471    sub gensym
472    {
473	my $name = "GEN" . $genseq++;
474	my $ref = \*{$name};
475	delete $::{$name};
476	return $ref;
477    }
478}
479