ffmpeg/doc/texi2pod.pl
Stefano Sabatini 299b8be2ec Remove a rule triggered by @man begin WORD WORDS. This rule only
outputs the section if WORDS has been defined in the list of options
flags.

The meaning of this rule is not clear, and not used by the FFmpeg
documentation system anyway.

Originally committed as revision 23542 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-06-08 23:03:11 +00:00

423 lines
12 KiB
Prolog
Executable File

#! /usr/bin/perl -w
# Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
# This file is part of GNU CC.
# GNU CC is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
# GNU CC is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with GNU CC; see the file COPYING. If not, write to
# the Free Software Foundation, 51 Franklin Street, Fifth Floor,
# Boston, MA 02110-1301 USA
# This does trivial (and I mean _trivial_) conversion of Texinfo
# markup to Perl POD format. It's intended to be used to extract
# something suitable for a manpage from a Texinfo document.
$output = 0;
$skipping = 0;
%sects = ();
$section = "";
@icstack = ();
@endwstack = ();
@skstack = ();
@instack = ();
$shift = "";
%defs = ();
$fnno = 1;
$inf = "";
$ibase = "";
while ($_ = shift) {
if (/^-D(.*)$/) {
if ($1 ne "") {
$flag = $1;
} else {
$flag = shift;
}
$value = "";
($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);
die "no flag specified for -D\n"
unless $flag ne "";
die "flags may only contain letters, digits, hyphens, dashes and underscores\n"
unless $flag =~ /^[a-zA-Z0-9_-]+$/;
$defs{$flag} = $value;
} elsif (/^-/) {
usage();
} else {
$in = $_, next unless defined $in;
$out = $_, next unless defined $out;
usage();
}
}
if (defined $in) {
$inf = gensym();
open($inf, "<$in") or die "opening \"$in\": $!\n";
$ibase = $1 if $in =~ m|^(.+)/[^/]+$|;
} else {
$inf = \*STDIN;
}
if (defined $out) {
open(STDOUT, ">$out") or die "opening \"$out\": $!\n";
}
while(defined $inf) {
while(<$inf>) {
# Certain commands are discarded without further processing.
/^\@(?:
[a-z]+index # @*index: useful only in complete manual
|need # @need: useful only in printed manual
|(?:end\s+)?group # @group .. @end group: ditto
|page # @page: ditto
|node # @node: useful only in .info file
|(?:end\s+)?ifnottex # @ifnottex .. @end ifnottex: use contents
)\b/x and next;
chomp;
# Look for filename and title markers.
/^\@setfilename\s+([^.]+)/ and $fn = $1, next;
/^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;
# Identify a man title but keep only the one we are interested in.
/^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {
if (exists $defs{$1}) {
$fn = $1;
$tl = postprocess($2);
}
next;
};
# Look for blocks surrounded by @c man begin SECTION ... @c man end.
# This really oughta be @ifman ... @end ifman and the like, but such
# would require rev'ing all other Texinfo translators.
/^\@c\s+man\s+begin\s+([A-Za-z ]+)/ and $sect = $1, $output = 1, next;
/^\@c\s+man\s+end/ and do {
$sects{$sect} = "" unless exists $sects{$sect};
$sects{$sect} .= postprocess($section);
$section = "";
$output = 0;
next;
};
# handle variables
/^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {
$defs{$1} = $2;
next;
};
/^\@clear\s+([a-zA-Z0-9_-]+)/ and do {
delete $defs{$1};
next;
};
next unless $output;
# Discard comments. (Can't do it above, because then we'd never see
# @c man lines.)
/^\@c\b/ and next;
# End-block handler goes up here because it needs to operate even
# if we are skipping.
/^\@end\s+([a-z]+)/ and do {
# Ignore @end foo, where foo is not an operation which may
# cause us to skip, if we are presently skipping.
my $ended = $1;
next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex)$/;
die "\@end $ended without \@$ended at line $.\n" unless defined $endw;
die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;
$endw = pop @endwstack;
if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex)$/) {
$skipping = pop @skstack;
next;
} elsif ($ended =~ /^(?:example|smallexample|display)$/) {
$shift = "";
$_ = ""; # need a paragraph break
} elsif ($ended =~ /^(?:itemize|enumerate|[fv]?table)$/) {
$_ = "\n=back\n";
$ic = pop @icstack;
} else {
die "unknown command \@end $ended at line $.\n";
}
};
# We must handle commands which can cause skipping even while we
# are skipping, otherwise we will not process nested conditionals
# correctly.
/^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
push @endwstack, $endw;
push @skstack, $skipping;
$endw = "ifset";
$skipping = 1 unless exists $defs{$1};
next;
};
/^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
push @endwstack, $endw;
push @skstack, $skipping;
$endw = "ifclear";
$skipping = 1 if exists $defs{$1};
next;
};
/^\@(ignore|menu|iftex)\b/ and do {
push @endwstack, $endw;
push @skstack, $skipping;
$endw = $1;
$skipping = 1;
next;
};
next if $skipping;
# Character entities. First the ones that can be replaced by raw text
# or discarded outright:
s/\@copyright\{\}/(c)/g;
s/\@dots\{\}/.../g;
s/\@enddots\{\}/..../g;
s/\@([.!? ])/$1/g;
s/\@[:-]//g;
s/\@bullet(?:\{\})?/*/g;
s/\@TeX\{\}/TeX/g;
s/\@pounds\{\}/\#/g;
s/\@minus(?:\{\})?/-/g;
s/\\,/,/g;
# Now the ones that have to be replaced by special escapes
# (which will be turned back into text by unmunge())
s/&/&amp;/g;
s/\@\{/&lbrace;/g;
s/\@\}/&rbrace;/g;
s/\@\@/&at;/g;
# Inside a verbatim block, handle @var specially.
if ($shift ne "") {
s/\@var\{([^\}]*)\}/<$1>/g;
}
# POD doesn't interpret E<> inside a verbatim block.
if ($shift eq "") {
s/</&lt;/g;
s/>/&gt;/g;
} else {
s/</&LT;/g;
s/>/&GT;/g;
}
# Single line command handlers.
/^\@include\s+(.+)$/ and do {
push @instack, $inf;
$inf = gensym();
# Try cwd and $ibase.
open($inf, "<" . $1)
or open($inf, "<" . $ibase . "/" . $1)
or die "cannot open $1 or $ibase/$1: $!\n";
next;
};
/^\@(?:section|unnumbered|unnumberedsec|center)\s+(.+)$/
and $_ = "\n=head2 $1\n";
/^\@subsection\s+(.+)$/
and $_ = "\n=head3 $1\n";
# Block command handlers:
/^\@itemize\s*(\@[a-z]+|\*|-)?/ and do {
push @endwstack, $endw;
push @icstack, $ic;
$ic = $1 ? $1 : "*";
$_ = "\n=over 4\n";
$endw = "itemize";
};
/^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
push @endwstack, $endw;
push @icstack, $ic;
if (defined $1) {
$ic = $1 . ".";
} else {
$ic = "1.";
}
$_ = "\n=over 4\n";
$endw = "enumerate";
};
/^\@([fv]?table)\s+(\@[a-z]+)/ and do {
push @endwstack, $endw;
push @icstack, $ic;
$endw = $1;
$ic = $2;
$ic =~ s/\@(?:samp|strong|key|gcctabopt|option|env)/B/;
$ic =~ s/\@(?:code|kbd)/C/;
$ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
$ic =~ s/\@(?:file)/F/;
$_ = "\n=over 4\n";
};
/^\@((?:small)?example|display)/ and do {
push @endwstack, $endw;
$endw = $1;
$shift = "\t";
$_ = ""; # need a paragraph break
};
/^\@itemx?\s*(.+)?$/ and do {
if (defined $1) {
# Entity escapes prevent munging by the <> processing below.
$_ = "\n=item $ic\&LT;$1\&GT;\n";
} else {
$_ = "\n=item $ic\n";
$ic =~ y/A-Ya-y/B-Zb-z/;
$ic =~ s/(\d+)/$1 + 1/eg;
}
};
$section .= $shift.$_."\n";
}
# End of current file.
close($inf);
$inf = pop @instack;
}
die "No filename or title\n" unless defined $fn && defined $tl;
$sects{NAME} = "$fn \- $tl\n";
$sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};
for $sect (qw(NAME SYNOPSIS DESCRIPTION OPTIONS EXAMPLES ENVIRONMENT FILES
BUGS NOTES FOOTNOTES SEEALSO AUTHORS COPYRIGHT)) {
if(exists $sects{$sect}) {
$head = $sect;
$head =~ s/SEEALSO/SEE ALSO/;
print "=head1 $head\n\n";
print scalar unmunge ($sects{$sect});
print "\n";
}
}
sub usage
{
die "usage: $0 [-D toggle...] [infile [outfile]]\n";
}
sub postprocess
{
local $_ = $_[0];
# @value{foo} is replaced by whatever 'foo' is defined as.
while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
if (! exists $defs{$2}) {
print STDERR "Option $2 not defined\n";
s/\Q$1\E//;
} else {
$value = $defs{$2};
s/\Q$1\E/$value/;
}
}
# Formatting commands.
# Temporary escape for @r.
s/\@r\{([^\}]*)\}/R<$1>/g;
s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
s/\@sc\{([^\}]*)\}/\U$1/g;
s/\@file\{([^\}]*)\}/F<$1>/g;
s/\@w\{([^\}]*)\}/S<$1>/g;
s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
# Cross references are thrown away, as are @noindent and @refill.
# (@noindent is impossible in .pod, and @refill is unnecessary.)
# @* is also impossible in .pod; we discard it and any newline that
# follows it. Similarly, our macro @gol must be discarded.
s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
s/;\s+\@pxref\{(?:[^\}]*)\}//g;
s/\@noindent\s*//g;
s/\@refill//g;
s/\@gol//g;
s/\@\*\s*\n?//g;
# @uref can take one, two, or three arguments, with different
# semantics each time. @url and @email are just like @uref with
# one argument, for our purposes.
s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;
s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
# Turn B<blah I<blah> blah> into B<blah> I<blah> B<blah> to
# match Texinfo semantics of @emph inside @samp. Also handle @r
# inside bold.
s/&LT;/</g;
s/&GT;/>/g;
1 while s/B<((?:[^<>]|I<[^<>]*>)*)R<([^>]*)>/B<$1>${2}B</g;
1 while (s/B<([^<>]*)I<([^>]+)>/B<$1>I<$2>B</g);
1 while (s/I<([^<>]*)B<([^>]+)>/I<$1>B<$2>I</g);
s/[BI]<>//g;
s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
# Extract footnotes. This has to be done after all other
# processing because otherwise the regexp will choke on formatting
# inside @footnote.
while (/\@footnote/g) {
s/\@footnote\{([^\}]+)\}/[$fnno]/;
add_footnote($1, $fnno);
$fnno++;
}
return $_;
}
sub unmunge
{
# Replace escaped symbols with their equivalents.
local $_ = $_[0];
s/&lt;/E<lt>/g;
s/&gt;/E<gt>/g;
s/&lbrace;/\{/g;
s/&rbrace;/\}/g;
s/&at;/\@/g;
s/&amp;/&/g;
return $_;
}
sub add_footnote
{
unless (exists $sects{FOOTNOTES}) {
$sects{FOOTNOTES} = "\n=over 4\n\n";
}
$sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
$sects{FOOTNOTES} .= $_[0];
$sects{FOOTNOTES} .= "\n\n";
}
# stolen from Symbol.pm
{
my $genseq = 0;
sub gensym
{
my $name = "GEN" . $genseq++;
my $ref = \*{$name};
delete $::{$name};
return $ref;
}
}