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diff --git a/contrib/perl5/lib/Pod/Usage.pm b/contrib/perl5/lib/Pod/Usage.pm new file mode 100644 index 0000000..aa8f712 --- /dev/null +++ b/contrib/perl5/lib/Pod/Usage.pm @@ -0,0 +1,544 @@ +############################################################################# +# Pod/Usage.pm -- print usage messages for the running script. +# +# Copyright (C) 1996-2000 by Bradford Appleton. All rights reserved. +# This file is part of "PodParser". PodParser is free software; +# you can redistribute it and/or modify it under the same terms +# as Perl itself. +############################################################################# + +package Pod::Usage; + +use vars qw($VERSION); +$VERSION = 1.12; ## Current version of this package +require 5.005; ## requires this Perl version or later + +=head1 NAME + +Pod::Usage, pod2usage() - print a usage message from embedded pod documentation + +=head1 SYNOPSIS + + use Pod::Usage + + my $message_text = "This text precedes the usage message."; + my $exit_status = 2; ## The exit status to use + my $verbose_level = 0; ## The verbose level to use + my $filehandle = \*STDERR; ## The filehandle to write to + + pod2usage($message_text); + + pod2usage($exit_status); + + pod2usage( { -message => $message_text , + -exitval => $exit_status , + -verbose => $verbose_level, + -output => $filehandle } ); + + pod2usage( -msg => $message_text , + -exitval => $exit_status , + -verbose => $verbose_level, + -output => $filehandle ); + +=head1 ARGUMENTS + +B<pod2usage> should be given either a single argument, or a list of +arguments corresponding to an associative array (a "hash"). When a single +argument is given, it should correspond to exactly one of the following: + +=over + +=item * + +A string containing the text of a message to print I<before> printing +the usage message + +=item * + +A numeric value corresponding to the desired exit status + +=item * + +A reference to a hash + +=back + +If more than one argument is given then the entire argument list is +assumed to be a hash. If a hash is supplied (either as a reference or +as a list) it should contain one or more elements with the following +keys: + +=over + +=item C<-message> + +=item C<-msg> + +The text of a message to print immediately prior to printing the +program's usage message. + +=item C<-exitval> + +The desired exit status to pass to the B<exit()> function. + +=item C<-verbose> + +The desired level of "verboseness" to use when printing the usage +message. If the corresponding value is 0, then only the "SYNOPSIS" +section of the pod documentation is printed. If the corresponding value +is 1, then the "SYNOPSIS" section, along with any section entitled +"OPTIONS", "ARGUMENTS", or "OPTIONS AND ARGUMENTS" is printed. If the +corresponding value is 2 or more then the entire manpage is printed. + +=item C<-output> + +A reference to a filehandle, or the pathname of a file to which the +usage message should be written. The default is C<\*STDERR> unless the +exit value is less than 2 (in which case the default is C<\*STDOUT>). + +=item C<-input> + +A reference to a filehandle, or the pathname of a file from which the +invoking script's pod documentation should be read. It defaults to the +file indicated by C<$0> (C<$PROGRAM_NAME> for users of F<English.pm>). + +=item C<-pathlist> + +A list of directory paths. If the input file does not exist, then it +will be searched for in the given directory list (in the order the +directories appear in the list). It defaults to the list of directories +implied by C<$ENV{PATH}>. The list may be specified either by a reference +to an array, or by a string of directory paths which use the same path +separator as C<$ENV{PATH}> on your system (e.g., C<:> for Unix, C<;> for +MSWin32 and DOS). + +=back + +=head1 DESCRIPTION + +B<pod2usage> will print a usage message for the invoking script (using +its embedded pod documentation) and then exit the script with the +desired exit status. The usage message printed may have any one of three +levels of "verboseness": If the verbose level is 0, then only a synopsis +is printed. If the verbose level is 1, then the synopsis is printed +along with a description (if present) of the command line options and +arguments. If the verbose level is 2, then the entire manual page is +printed. + +Unless they are explicitly specified, the default values for the exit +status, verbose level, and output stream to use are determined as +follows: + +=over + +=item * + +If neither the exit status nor the verbose level is specified, then the +default is to use an exit status of 2 with a verbose level of 0. + +=item * + +If an exit status I<is> specified but the verbose level is I<not>, then the +verbose level will default to 1 if the exit status is less than 2 and +will default to 0 otherwise. + +=item * + +If an exit status is I<not> specified but verbose level I<is> given, then +the exit status will default to 2 if the verbose level is 0 and will +default to 1 otherwise. + +=item * + +If the exit status used is less than 2, then output is printed on +C<STDOUT>. Otherwise output is printed on C<STDERR>. + +=back + +Although the above may seem a bit confusing at first, it generally does +"the right thing" in most situations. This determination of the default +values to use is based upon the following typical Unix conventions: + +=over + +=item * + +An exit status of 0 implies "success". For example, B<diff(1)> exits +with a status of 0 if the two files have the same contents. + +=item * + +An exit status of 1 implies possibly abnormal, but non-defective, program +termination. For example, B<grep(1)> exits with a status of 1 if +it did I<not> find a matching line for the given regular expression. + +=item * + +An exit status of 2 or more implies a fatal error. For example, B<ls(1)> +exits with a status of 2 if you specify an illegal (unknown) option on +the command line. + +=item * + +Usage messages issued as a result of bad command-line syntax should go +to C<STDERR>. However, usage messages issued due to an explicit request +to print usage (like specifying B<-help> on the command line) should go +to C<STDOUT>, just in case the user wants to pipe the output to a pager +(such as B<more(1)>). + +=item * + +If program usage has been explicitly requested by the user, it is often +desireable to exit with a status of 1 (as opposed to 0) after issuing +the user-requested usage message. It is also desireable to give a +more verbose description of program usage in this case. + +=back + +B<pod2usage> doesn't force the above conventions upon you, but it will +use them by default if you don't expressly tell it to do otherwise. The +ability of B<pod2usage()> to accept a single number or a string makes it +convenient to use as an innocent looking error message handling function: + + use Pod::Usage; + use Getopt::Long; + + ## Parse options + GetOptions("help", "man", "flag1") || pod2usage(2); + pod2usage(1) if ($opt_help); + pod2usage(-verbose => 2) if ($opt_man); + + ## Check for too many filenames + pod2usage("$0: Too many files given.\n") if (@ARGV > 1); + +Some user's however may feel that the above "economy of expression" is +not particularly readable nor consistent and may instead choose to do +something more like the following: + + use Pod::Usage; + use Getopt::Long; + + ## Parse options + GetOptions("help", "man", "flag1") || pod2usage(-verbose => 0); + pod2usage(-verbose => 1) if ($opt_help); + pod2usage(-verbose => 2) if ($opt_man); + + ## Check for too many filenames + pod2usage(-verbose => 2, -message => "$0: Too many files given.\n") + if (@ARGV > 1); + +As with all things in Perl, I<there's more than one way to do it>, and +B<pod2usage()> adheres to this philosophy. If you are interested in +seeing a number of different ways to invoke B<pod2usage> (although by no +means exhaustive), please refer to L<"EXAMPLES">. + +=head1 EXAMPLES + +Each of the following invocations of C<pod2usage()> will print just the +"SYNOPSIS" section to C<STDERR> and will exit with a status of 2: + + pod2usage(); + + pod2usage(2); + + pod2usage(-verbose => 0); + + pod2usage(-exitval => 2); + + pod2usage({-exitval => 2, -output => \*STDERR}); + + pod2usage({-verbose => 0, -output => \*STDERR}); + + pod2usage(-exitval => 2, -verbose => 0); + + pod2usage(-exitval => 2, -verbose => 0, -output => \*STDERR); + +Each of the following invocations of C<pod2usage()> will print a message +of "Syntax error." (followed by a newline) to C<STDERR>, immediately +followed by just the "SYNOPSIS" section (also printed to C<STDERR>) and +will exit with a status of 2: + + pod2usage("Syntax error."); + + pod2usage(-message => "Syntax error.", -verbose => 0); + + pod2usage(-msg => "Syntax error.", -exitval => 2); + + pod2usage({-msg => "Syntax error.", -exitval => 2, -output => \*STDERR}); + + pod2usage({-msg => "Syntax error.", -verbose => 0, -output => \*STDERR}); + + pod2usage(-msg => "Syntax error.", -exitval => 2, -verbose => 0); + + pod2usage(-message => "Syntax error.", + -exitval => 2, + -verbose => 0, + -output => \*STDERR); + +Each of the following invocations of C<pod2usage()> will print the +"SYNOPSIS" section and any "OPTIONS" and/or "ARGUMENTS" sections to +C<STDOUT> and will exit with a status of 1: + + pod2usage(1); + + pod2usage(-verbose => 1); + + pod2usage(-exitval => 1); + + pod2usage({-exitval => 1, -output => \*STDOUT}); + + pod2usage({-verbose => 1, -output => \*STDOUT}); + + pod2usage(-exitval => 1, -verbose => 1); + + pod2usage(-exitval => 1, -verbose => 1, -output => \*STDOUT}); + +Each of the following invocations of C<pod2usage()> will print the +entire manual page to C<STDOUT> and will exit with a status of 1: + + pod2usage(-verbose => 2); + + pod2usage({-verbose => 2, -output => \*STDOUT}); + + pod2usage(-exitval => 1, -verbose => 2); + + pod2usage({-exitval => 1, -verbose => 2, -output => \*STDOUT}); + +=head2 Recommended Use + +Most scripts should print some type of usage message to C<STDERR> when a +command line syntax error is detected. They should also provide an +option (usually C<-H> or C<-help>) to print a (possibly more verbose) +usage message to C<STDOUT>. Some scripts may even wish to go so far as to +provide a means of printing their complete documentation to C<STDOUT> +(perhaps by allowing a C<-man> option). The following complete example +uses B<Pod::Usage> in combination with B<Getopt::Long> to do all of these +things: + + use Getopt::Long; + use Pod::Usage; + + my $man = 0; + my $help = 0; + ## Parse options and print usage if there is a syntax error, + ## or if usage was explicitly requested. + GetOptions('help|?' => \$help, man => \$man) or pod2usage(2); + pod2usage(1) if $help; + pod2usage(-verbose => 2) if $man; + + ## If no arguments were given, then allow STDIN to be used only + ## if it's not connected to a terminal (otherwise print usage) + pod2usage("$0: No files given.") if ((@ARGV == 0) && (-t STDIN)); + __END__ + + =head1 NAME + + sample - Using GetOpt::Long and Pod::Usage + + =head1 SYNOPSIS + + sample [options] [file ...] + + Options: + -help brief help message + -man full documentation + + =head1 OPTIONS + + =over 8 + + =item B<-help> + + Print a brief help message and exits. + + =item B<-man> + + Prints the manual page and exits. + + =back + + =head1 DESCRIPTION + + B<This program> will read the given input file(s) and do something + useful with the contents thereof. + + =cut + +=head1 CAVEATS + +By default, B<pod2usage()> will use C<$0> as the path to the pod input +file. Unfortunately, not all systems on which Perl runs will set C<$0> +properly (although if C<$0> isn't found, B<pod2usage()> will search +C<$ENV{PATH}> or else the list specified by the C<-pathlist> option). +If this is the case for your system, you may need to explicitly specify +the path to the pod docs for the invoking script using something +similar to the following: + + pod2usage(-exitval => 2, -input => "/path/to/your/pod/docs"); + +=head1 AUTHOR + +Brad Appleton E<lt>bradapp@enteract.comE<gt> + +Based on code for B<Pod::Text::pod2text()> written by +Tom Christiansen E<lt>tchrist@mox.perl.comE<gt> + +=head1 ACKNOWLEDGEMENTS + +Steven McDougall E<lt>swmcd@world.std.comE<gt> for his help and patience +with re-writing this manpage. + +=cut + +############################################################################# + +use strict; +#use diagnostics; +use Carp; +use Exporter; +use File::Spec; + +use vars qw(@ISA @EXPORT); +@EXPORT = qw(&pod2usage); +BEGIN { + if ( $] >= 5.005_58 ) { + require Pod::Text; + @ISA = qw( Pod::Text ); + } + else { + require Pod::PlainText; + @ISA = qw( Pod::PlainText ); + } +} + + +##--------------------------------------------------------------------------- + +##--------------------------------- +## Function definitions begin here +##--------------------------------- + +sub pod2usage { + local($_) = shift || ""; + my %opts; + ## Collect arguments + if (@_ > 0) { + ## Too many arguments - assume that this is a hash and + ## the user forgot to pass a reference to it. + %opts = ($_, @_); + } + elsif (ref $_) { + ## User passed a ref to a hash + %opts = %{$_} if (ref($_) eq 'HASH'); + } + elsif (/^[-+]?\d+$/) { + ## User passed in the exit value to use + $opts{"-exitval"} = $_; + } + else { + ## User passed in a message to print before issuing usage. + $_ and $opts{"-message"} = $_; + } + + ## Need this for backward compatibility since we formerly used + ## options that were all uppercase words rather than ones that + ## looked like Unix command-line options. + ## to be uppercase keywords) + %opts = map { + my $val = $opts{$_}; + s/^(?=\w)/-/; + /^-msg/i and $_ = '-message'; + /^-exit/i and $_ = '-exitval'; + lc($_) => $val; + } (keys %opts); + + ## Now determine default -exitval and -verbose values to use + if ((! defined $opts{"-exitval"}) && (! defined $opts{"-verbose"})) { + $opts{"-exitval"} = 2; + $opts{"-verbose"} = 0; + } + elsif (! defined $opts{"-exitval"}) { + $opts{"-exitval"} = ($opts{"-verbose"} > 0) ? 1 : 2; + } + elsif (! defined $opts{"-verbose"}) { + $opts{"-verbose"} = ($opts{"-exitval"} < 2); + } + + ## Default the output file + $opts{"-output"} = ($opts{"-exitval"} < 2) ? \*STDOUT : \*STDERR + unless (defined $opts{"-output"}); + ## Default the input file + $opts{"-input"} = $0 unless (defined $opts{"-input"}); + + ## Look up input file in path if it doesnt exist. + unless ((ref $opts{"-input"}) || (-e $opts{"-input"})) { + my ($dirname, $basename) = ('', $opts{"-input"}); + my $pathsep = ($^O =~ /^(?:dos|os2|MSWin32)$/) ? ";" + : (($^O eq 'MacOS') ? ',' : ":"); + my $pathspec = $opts{"-pathlist"} || $ENV{PATH} || $ENV{PERL5LIB}; + + my @paths = (ref $pathspec) ? @$pathspec : split($pathsep, $pathspec); + for $dirname (@paths) { + $_ = File::Spec->catfile($dirname, $basename) if length; + last if (-e $_) && ($opts{"-input"} = $_); + } + } + + ## Now create a pod reader and constrain it to the desired sections. + my $parser = new Pod::Usage(USAGE_OPTIONS => \%opts); + if ($opts{"-verbose"} == 0) { + $parser->select("SYNOPSIS"); + } + elsif ($opts{"-verbose"} == 1) { + my $opt_re = '(?i)' . + '(?:OPTIONS|ARGUMENTS)' . + '(?:\s*(?:AND|\/)\s*(?:OPTIONS|ARGUMENTS))?'; + $parser->select( 'SYNOPSIS', $opt_re, "DESCRIPTION/$opt_re" ); + } + + ## Now translate the pod document and then exit with the desired status + $parser->parse_from_file($opts{"-input"}, $opts{"-output"}); + exit($opts{"-exitval"}); +} + +##--------------------------------------------------------------------------- + +##------------------------------- +## Method definitions begin here +##------------------------------- + +sub new { + my $this = shift; + my $class = ref($this) || $this; + my %params = @_; + my $self = {%params}; + bless $self, $class; + $self->initialize(); + return $self; +} + +sub begin_pod { + my $self = shift; + $self->SUPER::begin_pod(); ## Have to call superclass + my $msg = $self->{USAGE_OPTIONS}->{-message} or return 1; + my $out_fh = $self->output_handle(); + print $out_fh "$msg\n"; +} + +sub preprocess_paragraph { + my $self = shift; + local $_ = shift; + my $line = shift; + ## See if this is a heading and we arent printing the entire manpage. + if (($self->{USAGE_OPTIONS}->{-verbose} < 2) && /^=head/) { + ## Change the title of the SYNOPSIS section to USAGE + s/^=head1\s+SYNOPSIS\s*$/=head1 USAGE/; + ## Try to do some lowercasing instead of all-caps in headings + s{([A-Z])([A-Z]+)}{((length($2) > 2) ? $1 : lc($1)) . lc($2)}ge; + ## Use a colon to end all headings + s/\s*$/:/ unless (/:\s*$/); + $_ .= "\n"; + } + return $self->SUPER::preprocess_paragraph($_); +} + |
