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