doc: Update to latest help2man

This fixes bug#27773.

* doc/help2man: Sync with version 1.47.3 to support reproducible
builds by using $SOURCE_DATE_EPOCH.

2 files changed, 176 insertions, 76 deletions

diff --git a/doc/Makefile.inc b/doc/Makefile.inc
index b39ce89c7..18c137c5b 100644
--- a/doc/Makefile.inc
+++ b/doc/Makefile.inc
@@ -32,6 +32,7 @@ man1_MANS = \
 $(man1_MANS): $(top_srcdir)/configure.ac
 
 CLEANFILES += $(man1_MANS)
+# XXX: This script should be updated with 'fetch' target.
 EXTRA_DIST += %D%/help2man
 
 update_mans = \
diff --git a/doc/help2man b/doc/help2man
index e651b8d2d..829a8713b 100755
--- a/doc/help2man
+++ b/doc/help2man
@@ -1,7 +1,8 @@
 #!/usr/bin/perl -w
 
 # Generate a short man page from --help and --version output.
-# Copyright (C) 1997-2017 Free Software Foundation, Inc.
+# Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2009,
+# 2010, 2011, 2012, 2013, 2014, 2015 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,14 +20,15 @@
 # Written by Brendan O'Dea <bod@debian.org>
 # Available from ftp://ftp.gnu.org/gnu/help2man/
 
-use 5.006;
+use 5.008;
 use strict;
 use Getopt::Long;
+use Text::ParseWords qw(shellwords);
 use Text::Tabs qw(expand);
 use POSIX qw(strftime setlocale LC_ALL);
 
 my $this_program = 'help2man';
-my $this_version = '1.40.8';
+my $this_version = '1.47.4';
 
 sub _ { $_[0] }
 sub configure_locale
@@ -42,11 +44,16 @@ sub enc_user { $_[0] }
 sub kark { die +(sprintf shift, @_), "\n" }
 sub N_ { $_[0] }
 
+sub program_basename;
+sub get_option_value;
+sub convert_option;
+sub fix_italic_spacing;
+
 my $version_info = enc_user sprintf _(<<'EOT'), $this_program, $this_version;
 GNU %s %s
 
 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2009, 2010,
-2011, 2012 Free Software Foundation, Inc.
+2011, 2012, 2013, 2014, 2015 Free Software Foundation, Inc.
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
@@ -117,18 +124,32 @@ Getopt::Long::config('bundling');
 die $help_info unless GetOptions %opt_def and @ARGV == 1;
 
 my %include = ();
+my %replace = ();
 my %append = ();
-my @include = (); # retain order given in include file
+my %append_match = ();
+my @sections = ();  # retain order of include file or in-line *section*s
 
 # Process include file (if given).  Format is:
 #
-#   [section name]
-#   verbatim text
+#   Optional initial text, ignored.  May include lines starting with `-'
+#   which are processed as options.
+#
+#   [section]
+#   Verbatim text to be included in the named section.  By default at
+#   the start, but in the case of `name' and `synopsis' the content
+#   will replace the autogenerated contents.
 #
-# or
+#   [<section]
+#   Verbatim text to be inserted at the start of the named section.
+#
+#   [=section]
+#   Verbatim text to replace the named section.
+#
+#   [>section]
+#   Verbatim text to be appended to the end of the named section.
 #
 #   /pattern/
-#   verbatim text
+#   Verbatim text for inclusion below a paragraph matching `pattern'.
 #
 
 while (@opt_include)
@@ -140,7 +161,7 @@ while (@opt_include)
 	unless open INC, $inc;
 
     my $key;
-    my $hash = \%include;
+    my $hash;
 
     while (<INC>)
     {
@@ -155,7 +176,23 @@ while (@opt_include)
 	    $key =~ s/^\s+//;
 	    $key =~ s/\s+$//;
 	    $hash = \%include;
-	    push @include, $key unless $include{$key};
+	    # Handle explicit [<section], [=section] and [>section]
+	    if ($key =~ s/^([<>=])\s*//)
+	    {
+		if    ($1 eq '>') { $hash = \%append; }
+		elsif ($1 eq '=') { $hash = \%replace; }
+	    }
+	    # NAME/SYNOPSIS replace by default
+	    elsif ($key eq _('NAME') or $key eq _('SYNOPSIS'))
+	    {
+		$hash = \%replace;
+	    }
+	    else
+	    {
+		$hash = \%include;
+	    }
+
+	    push @sections, $key;
 	    next;
 	}
 
@@ -172,7 +209,7 @@ while (@opt_include)
 		die "$inc:$.:$@";
 	    }
 
-	    $hash = \%append;
+	    $hash = \%append_match;
 	    next;
 	}
 
@@ -184,48 +221,57 @@ while (@opt_include)
 	    # handle options
 	    if (/^-/)
 	    {
-		local @ARGV = split;
+		local @ARGV = shellwords $_;
 		GetOptions %opt_def;
 	    }
 
 	    next;
 	}
 
-	$hash->{$key} ||= '';
 	$hash->{$key} .= $_;
     }
 
     close INC;
 
     kark N_("%s: no valid information found in `%s'"), $this_program, $inc
-    	unless $key;
+	unless $key;
 }
 
 # Compress trailing blank lines.
-for my $hash (\(%include, %append))
+for my $hash (\(%include, %replace, %append, %append_match))
 {
     for (keys %$hash) { $hash->{$_} =~ s/\n+$/\n/ }
 }
 
-sub get_option_value;
-
 # Grab help and version info from executable.
 my $help_text   = get_option_value $ARGV[0], $help_option;
 $version_text ||= get_option_value $ARGV[0], $version_option;
 
+# By default the generated manual pages will include the current date.  This may
+# however be overriden by setting the environment variable $SOURCE_DATE_EPOCH
+# to an integer value of the seconds since the UNIX epoch.  This is primarily
+# intended to support reproducible builds (wiki.debian.org/ReproducibleBuilds)
+# and will additionally ensure that the output date string is UTC.
+my $epoch_secs = time;
+if (exists $ENV{SOURCE_DATE_EPOCH} and $ENV{SOURCE_DATE_EPOCH} =~ /^(\d+)$/)
+{
+    $epoch_secs = $1;
+    $ENV{TZ} = 'UTC';
+}
+
 # Translators: the following message is a strftime(3) format string, which in
 # the English version expands to the month as a word and the full year.  It
 # is used on the footer of the generated manual pages.  If in doubt, you may
 # just use %x as the value (which should be the full locale-specific date).
-my $date = enc strftime _("%B %Y"), localtime;
-(my $program = $ARGV[0]) =~ s!.*/!!;
+my $date = enc strftime _("%B %Y"), localtime $epoch_secs;
+my $program = program_basename $ARGV[0];
 my $package = $program;
 my $version;
 
 if ($opt_output)
 {
     unlink $opt_output or kark N_("%s: can't unlink %s (%s)"),
-    	$this_program, $opt_output, $! if -e $opt_output;
+	$this_program, $opt_output, $! if -e $opt_output;
 
     open STDOUT, ">$opt_output"
 	or kark N_("%s: can't create %s (%s)"), $this_program, $opt_output, $!;
@@ -247,14 +293,14 @@ if ($opt_output)
 if (/^(\S+) +\(((?:GNU|Free) +[^)]+)\) +(.*)/ or
     /^(\S+) +- *((?:GNU|Free) +\S+) +(.*)/)
 {
-    $program = $1;
+    $program = program_basename $1;
     $package = $2;
     $version = $3;
 }
 elsif (/^((?:GNU|Free) +)?(\S+) +(.*)/)
 {
-    $program = $2;
-    $package = $1 ? "$1$2" : $2;
+    $program = program_basename $2;
+    $package = $1 ? "$1$program" : $program;
     $version = $3;
 }
 else
@@ -262,21 +308,21 @@ else
     $version = $_;
 }
 
-$program =~ s!.*/!!;
-
 # No info for `info' itself.
 $opt_no_info = 1 if $program eq 'info';
 
+if ($opt_name)
+{
+    # --name overrides --include contents.
+    $replace{_('NAME')} = "$program \\- $opt_name\n";
+}
+
 # Translators: "NAME", "SYNOPSIS" and other one or two word strings in all
 # upper case are manual page section headings.  The man(1) manual page in your
 # language, if available should provide the conventional translations.
-for ($include{_('NAME')})
+for ($replace{_('NAME')} || ($include{_('NAME')} ||= ''))
 {
-    if ($opt_name) # --name overrides --include contents.
-    {
-	$_ = "$program \\- $opt_name\n";
-    }
-    elsif ($_) # Use first name given as $program
+    if ($_) # Use first name given as $program
     {
 	$program = $1 if /^([^\s,]+)(?:,?\s*[^\s,\\-]+)*\s+\\?-/;
     }
@@ -339,10 +385,11 @@ if ($help_text =~ s/^($PAT_USAGE):( +(\S+))(.*)((?:\n(?: {6}\1| *($PAT_USAGE_CON
 	s/\\fI$//;
 	s/^\./\\&./;
 
+	$_ = fix_italic_spacing $_;
 	$synopsis .= "$_\n";
     }
 
-    $include{_('SYNOPSIS')} ||= $synopsis;
+    $include{_('SYNOPSIS')} .= $synopsis;
 }
 
 # Process text, initial section is DESCRIPTION.
@@ -371,13 +418,13 @@ s/\\/\x82/g;
 # "(?:[\\w-]+ +)?" in the bug reporting pattern is used to indicate an
 # optional word, so that either "Report bugs" or "Report _program_ bugs" will
 # be matched.
-my $PAT_BUGS		= _('Report +(?:[\w-]+ +)?bugs|Email +bug +reports +to');
-my $PAT_AUTHOR		= _('Written +by');
-my $PAT_OPTIONS		= _('Options');
-my $PAT_ENVIRONMENT	= _('Environment');
-my $PAT_FILES		= _('Files');
-my $PAT_EXAMPLES	= _('Examples');
-my $PAT_FREE_SOFTWARE	= _('This +is +free +software');
+my $PAT_BUGS          = _('Report +(?:[\w-]+ +)?bugs|Email +bug +reports +to');
+my $PAT_AUTHOR        = _('Written +by');
+my $PAT_OPTIONS       = _('Options');
+my $PAT_ENVIRONMENT   = _('Environment');
+my $PAT_FILES         = _('Files');
+my $PAT_EXAMPLES      = _('Examples');
+my $PAT_FREE_SOFTWARE = _('This +is +free +software');
 
 # Start a new paragraph (if required) for these.
 s/([^\n])\n($PAT_BUGS|$PAT_AUTHOR) /$1\n\n$2 /og;
@@ -386,33 +433,40 @@ s/([^\n])\n($PAT_BUGS|$PAT_AUTHOR) /$1\n\n$2 /og;
 # character.
 s/^Copyright +(?:\xa9|\([Cc]\))/Copyright \\(co/mg;
 
-sub convert_option;
-
 while (length)
 {
     # Convert some standard paragraph names.
-    if (s/^($PAT_OPTIONS): *\n//o)
+    if (s/^($PAT_OPTIONS): *\n+//o)
     {
 	$sect = _('OPTIONS');
 	next;
     }
-    if (s/^($PAT_ENVIRONMENT): *\n//o)
+    if (s/^($PAT_ENVIRONMENT): *\n+//o)
     {
 	$sect = _('ENVIRONMENT');
 	next;
     }
-    if (s/^($PAT_FILES): *\n//o)
+    if (s/^($PAT_FILES): *\n+//o)
     {
 	$sect = _('FILES');
 	next;
     }
-    elsif (s/^($PAT_EXAMPLES): *\n//o)
+    elsif (s/^($PAT_EXAMPLES): *\n+//o)
     {
 	$sect = _('EXAMPLES');
 	next;
     }
 
-    # Copyright section
+    # Custom section indicated by a line containing "*Section Name*".
+    if (s/^\*(\w(.*\w)?)\* *\n+//)
+    {
+	$sect = uc $1;
+	$sect =~ tr/*/ /;  # also accept *Section*Name*
+	push @sections, $sect;
+	next;
+    }
+
+    # Copyright section.
     if (/^Copyright /)
     {
 	$sect = _('COPYRIGHT');
@@ -437,7 +491,6 @@ while (length)
 	my $indent = $1;
 	my $prefix = $2;
 	my $break = '.IP';
-	$include{$sect} ||= '';
 	while (s/^$indent\Q$prefix\E(\S.*)\n*//)
 	{
 	    $include{$sect} .= "$break\n\\f(CW$prefix$1\\fR\n";
@@ -448,12 +501,11 @@ while (length)
     }
 
     my $matched = '';
-    $include{$sect} ||= '';
 
     # Sub-sections have a trailing colon and the second line indented.
     if (s/^(\S.*:) *\n / /)
     {
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$include{$sect} .= qq(.SS "$1"\n);
     }
 
@@ -463,7 +515,7 @@ while (length)
     # Option with description.
     if (s/^( {1,10}([+-]\S.*?))(?:(  +(?!-))|\n( {20,}))(\S.*)\n//)
     {
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$indent = length ($4 || "$1$3");
 	$content = ".TP\n\x84$2\n\x84$5\n";
 	unless ($4)
@@ -476,23 +528,23 @@ while (length)
     # Option without description.
     elsif (s/^ {1,10}([+-]\S.*)\n//)
     {
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$content = ".HP\n\x84$1\n";
 	$indent = 80; # not continued
     }
 
     # Indented paragraph with tag.
-    elsif (s/^( +(\S.*?)  +)(\S.*)\n//)
+    elsif (s/^( +(\S.*?))(?:(  +)|\n( {20,}))(\S.*)\n//)
     {
-	$matched .= $& if %append;
-	$indent = length $1;
-	$content = ".TP\n\x84$2\n\x84$3\n";
+	$matched .= $& if %append_match;
+	$indent = length ($4 || "$1$3");
+	$content = ".TP\n\x84$2\n\x84$5\n";
     }
 
     # Indented paragraph.
     elsif (s/^( +)(\S.*)\n//)
     {
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$indent = length $1;
 	$content = ".IP\n\x84$2\n";
     }
@@ -501,7 +553,7 @@ while (length)
     else
     {
 	s/(.*)\n//;
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$content = ".PP\n" if $include{$sect};
 	$content .= "$1\n";
     }
@@ -509,7 +561,7 @@ while (length)
     # Append continuations.
     while ($indent ? s/^ {$indent}(\S.*)\n// : s/^(\S.*)\n//)
     {
-	$matched .= $& if %append;
+	$matched .= $& if %append_match;
 	$content .= "\x84$1\n";
     }
 
@@ -523,19 +575,35 @@ while (length)
 	s/\x84'/\x81/g;
 	s/\x84//g;
 
-	# Convert options.
-	s/(^| |\()(-[][\w=-]+)/$1 . convert_option $2/mge;
+	# Examples should be verbatim.
+	unless ($sect eq _('EXAMPLES'))
+	{
+	    # Convert options.
+	    s/(^|[ (])(-[][\w=-]+)/$1 . convert_option $2/mge;
+
+	    # Italicise filenames: /a/b, $VAR/c/d, ~/e/f
+	    s!
+		(^|[ (])			# space/punctuation before
+		(
+		    (?:\$\w+|~)?		# leading variable, or tilde
+		    (?:/\w(?:[\w.-]*\w)?)+	# path components
+		)
+		($|[ ,;.)])			# space/punctuation after
+	    !$1\\fI$2\\fP$3!xmg;
+
+	    $_ = fix_italic_spacing $_;
+	}
 
-	# Escape remaining hyphens
+	# Escape remaining hyphens.
 	s/-/\x83/g;
 
-	if ($sect eq 'COPYRIGHT')
+	if ($sect eq _('COPYRIGHT'))
 	{
 	    # Insert line breaks before additional copyright messages
 	    # and the disclaimer.
 	    s/\n(Copyright |$PAT_FREE_SOFTWARE)/\n.br\n$1/og;
 	}
-	elsif ($sect eq 'REPORTING BUGS')
+	elsif ($sect eq _('REPORTING BUGS'))
 	{
 	    # Handle multi-line bug reporting sections of the form:
 	    #
@@ -547,14 +615,14 @@ while (length)
     }
 
     # Check if matched paragraph contains /pat/.
-    if (%append)
+    if (%append_match)
     {
-	for my $pat (keys %append)
+	for my $pat (keys %append_match)
 	{
 	    if ($matched =~ $pat)
 	    {
-		$content .= ".PP\n" unless $append{$pat} =~ /^\./;
-		$content .= $append{$pat};
+		$content .= ".PP\n" unless $append_match{$pat} =~ /^\./;
+		$content .= $append_match{$pat};
 	    }
 	}
     }
@@ -568,7 +636,6 @@ unless ($opt_no_info)
     my $info_page = $opt_info || $program;
 
     $sect = _('SEE ALSO');
-    $include{$sect} ||= '';
     $include{$sect} .= ".PP\n" if $include{$sect};
     $include{$sect} .= sprintf _(<<'EOT'), $program, $program, $info_page;
 The full documentation for
@@ -585,6 +652,18 @@ should give you access to the complete manual.
 EOT
 }
 
+# Append additional text.
+while (my ($sect, $text) = each %append)
+{
+    $include{$sect} .= $append{$sect};
+}
+
+# Replace sections.
+while (my ($sect, $text) = each %replace)
+{
+    $include{$sect} = $replace{$sect};
+}
+
 # Output header.
 print <<EOT;
 .\\" DO NOT MODIFY THIS FILE!  It was generated by $this_program $this_version.
@@ -592,15 +671,17 @@ print <<EOT;
 EOT
 
 # Section ordering.
-my @pre = (_('NAME'), _('SYNOPSIS'), _('DESCRIPTION'), _('OPTIONS'),
-    _('ENVIRONMENT'), _('FILES'), _('EXAMPLES'));
-
-my @post = (_('AUTHOR'), _('REPORTING BUGS'), _('COPYRIGHT'), _('SEE ALSO'));
-my $filter = join '|', @pre, @post;
+my @pre = (_('NAME'), _('SYNOPSIS'), _('DESCRIPTION'), _('OPTIONS'));
+my @post = (_('ENVIRONMENT'), _('FILES'), _('EXAMPLES'), _('AUTHOR'),
+    _('REPORTING BUGS'), _('COPYRIGHT'), _('SEE ALSO'));
+my %filter = map { $_ => 1 } @pre, @post;
 
 # Output content.
-for my $sect (@pre, (grep ! /^($filter)$/o, @include), @post)
+my %done;
+for my $sect (@pre, (grep !$filter{$_}, @sections), @post)
 {
+    next if $done{$sect}++;  # ignore duplicates
+    next unless $include{$sect};
     if ($include{$sect})
     {
 	my $quote = $sect =~ /\W/ ? '"' : '';
@@ -628,6 +709,15 @@ close STDOUT or kark N_("%s: error writing to %s (%s)"), $this_program,
 
 exit;
 
+# Get program basename, and strip libtool "lt-" prefix if required.
+sub program_basename
+{
+    local $_ = shift;
+    s!.*/!!;
+    s/^lt-// if $opt_libtool;
+    $_;
+}
+
 # Call program with given option and return results.
 sub get_option_value
 {
@@ -648,7 +738,7 @@ sub get_option_value
 	kark $err, $this_program, $opt, $prog, $extra;
     }
 
-    return $value;
+    $value;
 }
 
 # Convert option dashes to \- to stop nroff from hyphenating 'em, and
@@ -667,3 +757,12 @@ sub convert_option
 
     $_;
 }
+
+# Insert spacing escape characters \, and \/ before and after italic text.  See
+# http://www.gnu.org/software/groff/manual/html_node/Ligatures-and-Kerning.html
+sub fix_italic_spacing
+{
+    local $_ = shift;
+    s!\\fI(.*?)\\f([BRP])!\\fI\\,$1\\/\\f$2!g;
+    return $_;
+}