1#! /usr/bin/perl -w
2
3#   Copyright (C) 1999-2014 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 3, 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	    $ic = pop @icstack;
168	} else {
169	    die "unknown command \@end $ended at line $.\n";
170	}
171    };
172
173    # We must handle commands which can cause skipping even while we
174    # are skipping, otherwise we will not process nested conditionals
175    # correctly.
176    /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
177	push @endwstack, $endw;
178	push @skstack, $skipping;
179	$endw = "ifset";
180	$skipping = 1 unless exists $defs{$1};
181	next;
182    };
183
184    /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
185	push @endwstack, $endw;
186	push @skstack, $skipping;
187	$endw = "ifclear";
188	$skipping = 1 if exists $defs{$1};
189	next;
190    };
191
192    /^\@(ignore|menu|iftex|copying)\b/ and do {
193	push @endwstack, $endw;
194	push @skstack, $skipping;
195	$endw = $1;
196	$skipping = 1;
197	next;
198    };
199
200    next if $skipping;
201
202    # Character entities.  First the ones that can be replaced by raw text
203    # or discarded outright:
204    s/\@copyright\{\}/(c)/g;
205    s/\@dots\{\}/.../g;
206    s/\@enddots\{\}/..../g;
207    s/\@([.!? ])/$1/g;
208    s/\@[:-]//g;
209    s/\@bullet(?:\{\})?/*/g;
210    s/\@TeX\{\}/TeX/g;
211    s/\@pounds\{\}/\#/g;
212    s/\@minus(?:\{\})?/-/g;
213    s/\\,/,/g;
214
215    # Now the ones that have to be replaced by special escapes
216    # (which will be turned back into text by unmunge())
217    # Replace @@ before @{ and @} in order to parse @samp{@@} correctly.
218    s/&/&amp;/g;
219    s/\@\@/&at;/g;
220    s/\@\{/&lbrace;/g;
221    s/\@\}/&rbrace;/g;
222    s/\@`\{(.)\}/&$1grave;/g;
223
224    # Inside a verbatim block, handle @var, @samp and @url specially.
225    if ($shift ne "") {
226	s/\@var\{([^\}]*)\}/<$1>/g;
227	s/\@samp\{([^\}]*)\}/"$1"/g;
228	s/\@url\{([^\}]*)\}/<$1>/g;
229    }
230
231    # POD doesn't interpret E<> inside a verbatim block.
232    if ($shift eq "") {
233	s/</&lt;/g;
234	s/>/&gt;/g;
235    } else {
236	s/</&LT;/g;
237	s/>/&GT;/g;
238    }
239
240    # Single line command handlers.
241
242    /^\@include\s+(.+)$/ and do {
243	push @instack, $inf;
244	$inf = gensym();
245	$file = postprocess($1);
246
247	# Try cwd and $ibase, then explicit -I paths.
248	$done = 0;
249	foreach $path ("", $ibase, @ipath) {
250	    $mypath = $file;
251	    $mypath = $path . "/" . $mypath if ($path ne "");
252	    open($inf, "<" . $mypath) and ($done = 1, last);
253	}
254	die "cannot find $file" if !$done;
255	next;
256    };
257
258    /^\@(?:section|unnumbered|unnumberedsec|center|heading)\s+(.+)$/
259	and $_ = "\n=head2 $1\n";
260    /^\@subsection\s+(.+)$/
261	and $_ = "\n=head3 $1\n";
262    /^\@subsubsection\s+(.+)$/
263	and $_ = "\n=head4 $1\n";
264
265    # Block command handlers:
266    /^\@itemize(?:\s+(\@[a-z]+|\*|-))?/ and do {
267	push @endwstack, $endw;
268	push @icstack, $ic;
269	if (defined $1) {
270	    $ic = $1;
271	} else {
272	    $ic = '*';
273	}
274	$_ = "\n=over 4\n";
275	$endw = "itemize";
276    };
277
278    /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
279	push @endwstack, $endw;
280	push @icstack, $ic;
281	if (defined $1) {
282	    $ic = $1 . ".";
283	} else {
284	    $ic = "1.";
285	}
286	$_ = "\n=over 4\n";
287	$endw = "enumerate";
288    };
289
290    /^\@multitable\s.*/ and do {
291	push @endwstack, $endw;
292	push @icstack, $ic;
293	$endw = "multitable";
294	$ic = "";
295	$_ = "\n=over 4\n";
296    };
297
298    /^\@([fv]?table)\s+(\@[a-z]+)/ and do {
299	push @endwstack, $endw;
300	push @icstack, $ic;
301	$endw = $1;
302	$ic = $2;
303	$ic =~ s/\@(?:samp|strong|key|gcctabopt|env)/B/;
304	$ic =~ s/\@(?:code|kbd)/C/;
305	$ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
306	$ic =~ s/\@(?:file)/F/;
307	$ic =~ s/\@(?:asis)//;
308	$_ = "\n=over 4\n";
309    };
310
311    /^\@((?:small)?example|display)/ and do {
312	push @endwstack, $endw;
313	$endw = $1;
314	$shift = "\t";
315	$_ = "";	# need a paragraph break
316    };
317
318    /^\@(headitem|item)\s+(.*\S)\s*$/ and $endw eq "multitable" and do {
319	@columns = ();
320	$item = $1;
321	for $column (split (/\s*\@tab\s*/, $2)) {
322	    # @strong{...} is used a @headitem work-alike
323	    $column =~ s/^\@strong\{(.*)\}$/$1/;
324	    $column = "I<$column>" if $item eq "headitem";
325	    push @columns, $column;
326	}
327	$_ = "\n=item ".join (" : ", @columns)."\n";
328    };
329
330    /^\@itemx?\s*(.+)?$/ and do {
331	if (defined $1) {
332            if ($ic) {
333		if ($endw eq "enumerate") {
334		    $_ = "\n=item $ic $1\n";
335		    $ic =~ s/(\d+)/$1 + 1/eg;
336		} else {
337		    # Entity escapes prevent munging by the <>
338		    # processing below.
339		    $_ = "\n=item $ic\&LT;$1\&GT;\n";
340		}
341            } else {
342                $_ = "\n=item $1\n";
343            }
344	} else {
345	    $_ = "\n=item Z\&LT;\&GT;$ic\n";
346	    $ic =~ y/A-Ya-y/B-Zb-z/;
347	    $ic =~ s/(\d+)/$1 + 1/eg;
348	}
349    };
350
351    $section .= $shift.$_."\n";
352}
353# End of current file.
354close($inf);
355$inf = pop @instack;
356}
357
358die "No filename or title\n" unless defined $fn && defined $tl;
359
360$sects{NAME} = "$fn \- $tl\n";
361$sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};
362
363for $sect (qw(NAME SYNOPSIS DESCRIPTION OPTIONS ENVIRONMENT FILES
364	      BUGS NOTES FOOTNOTES SEEALSO AUTHOR COPYRIGHT)) {
365    if(exists $sects{$sect}) {
366	$head = $sect;
367	$head =~ s/SEEALSO/SEE ALSO/;
368	print "=head1 $head\n\n";
369	print scalar unmunge ($sects{$sect});
370	print "\n";
371    }
372}
373
374sub usage
375{
376    die "usage: $0 [-D toggle...] [infile [outfile]]\n";
377}
378
379sub postprocess
380{
381    local $_ = $_[0];
382
383    # @value{foo} is replaced by whatever 'foo' is defined as.
384    while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
385	if (! exists $defs{$2}) {
386	    print STDERR "Option $2 not defined\n";
387	    s/\Q$1\E//;
388	} else {
389	    $value = $defs{$2};
390	    s/\Q$1\E/$value/;
391	}
392    }
393
394    # Formatting commands.
395    # Temporary escape for @r.
396    s/\@r\{([^\}]*)\}/R<$1>/g;
397    s/\@sc\{([^\}]*)\}/\U$1/g;
398    s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
399    s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
400    s/\@(?:samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
401    s/\@acronym\{([^\}]*)\}/\U$1/g;
402    s/\@file\{([^\}]*)\}/F<$1>/g;
403    s/\@w\{([^\}]*)\}/S<$1>/g;
404    s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
405    s/\@\///g;
406    s/\@t\{([^\}]*)\}/$1/g;
407
408    # keep references of the form @ref{...}, print them bold
409    s/\@(?:ref)\{([^\}]*)\}/B<$1>/g;
410
411    # Change double single quotes to double quotes.
412    s/''/"/g;
413    s/``/"/g;
414
415    # Cross references are thrown away, as are @noindent and @refill.
416    # (@noindent is impossible in .pod, and @refill is unnecessary.)
417    # @* is also impossible in .pod; we discard it and any newline that
418    # follows it.  Similarly, our macro @gol must be discarded.
419
420    s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
421    s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
422    s/;\s+\@pxref\{(?:[^\}]*)\}//g;
423    s/\@noindent\s*//g;
424    s/\@refill//g;
425    s/\@gol//g;
426    s/\@\*\s*\n?//g;
427
428    # Anchors are thrown away
429    s/\@anchor\{(?:[^\}]*)\}//g;
430
431    # @uref can take one, two, or three arguments, with different
432    # semantics each time.  @url and @email are just like @uref with
433    # one argument, for our purposes.
434    s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;
435    s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
436    s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
437
438    # Handle gccoptlist here, so it can contain the above formatting
439    # commands.
440    s/\@gccoptlist\{([^\}]*)\}/B<$1>/g;
441
442    # Un-escape <> at this point.
443    s/&LT;/</g;
444    s/&GT;/>/g;
445
446    # Now un-nest all B<>, I<>, R<>.  Theoretically we could have
447    # indefinitely deep nesting; in practice, one level suffices.
448    1 while s/([BIR])<([^<>]*)([BIR])<([^<>]*)>/$1<$2>$3<$4>$1</g;
449
450    # Replace R<...> with bare ...; eliminate empty markup, B<>;
451    # shift white space at the ends of [BI]<...> expressions outside
452    # the expression.
453    s/R<([^<>]*)>/$1/g;
454    s/[BI]<>//g;
455    s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
456    s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
457
458    # Extract footnotes.  This has to be done after all other
459    # processing because otherwise the regexp will choke on formatting
460    # inside @footnote.
461    while (/\@footnote/g) {
462	s/\@footnote\{([^\}]+)\}/[$fnno]/;
463	add_footnote($1, $fnno);
464	$fnno++;
465    }
466
467    return $_;
468}
469
470sub unmunge
471{
472    # Replace escaped symbols with their equivalents.
473    local $_ = $_[0];
474
475    s/&(.)grave;/E<$1grave>/g;
476    s/&lt;/E<lt>/g;
477    s/&gt;/E<gt>/g;
478    s/&lbrace;/\{/g;
479    s/&rbrace;/\}/g;
480    s/&at;/\@/g;
481    s/&amp;/&/g;
482    return $_;
483}
484
485sub add_footnote
486{
487    unless (exists $sects{FOOTNOTES}) {
488	$sects{FOOTNOTES} = "\n=over 4\n\n";
489    }
490
491    $sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
492    $sects{FOOTNOTES} .= $_[0];
493    $sects{FOOTNOTES} .= "\n\n";
494}
495
496# stolen from Symbol.pm
497{
498    my $genseq = 0;
499    sub gensym
500    {
501	my $name = "GEN" . $genseq++;
502	my $ref = \*{$name};
503	delete $::{$name};
504	return $ref;
505    }
506}
507