[perl5.git] / lib / Pod / Find.pm

#############################################################################  
# Pod/Find.pm -- finds files containing POD documentation
#
# Author: Marek Rouchal <marek@saftsack.fs.uni-bayreuth.de>
# 
# Copyright (C) 1999-2000 by Marek Rouchal (and borrowing code
# from Nick Ing-Simmon's PodToHtml). All rights reserved.
# This file is part of "PodParser". Pod::Find is free software;
# you can redistribute it and/or modify it under the same terms
# as Perl itself.
#############################################################################

package Pod::Find;

use vars qw($VERSION);
$VERSION = 0.21;   ## Current version of this package
require  5.005;   ## requires this Perl version or later
use Carp;

#############################################################################

=head1 NAME

Pod::Find - find POD documents in directory trees

=head1 SYNOPSIS

  use Pod::Find qw(pod_find simplify_name);
  my %pods = pod_find({ -verbose => 1, -inc => 1 });
  foreach(keys %pods) {
     print "found library POD `$pods{$_}' in $_\n";
  }

  print "podname=",simplify_name('a/b/c/mymodule.pod'),"\n";

  $location = pod_where( { -inc => 1 }, "Pod::Find" );

=head1 DESCRIPTION

B<Pod::Find> provides a set of functions to locate POD files.  Note that
no function is exported by default to avoid pollution of your namespace,
so be sure to specify them in the B<use> statement if you need them:

  use Pod::Find qw(pod_find);

=cut

use strict;
#use diagnostics;
use Exporter;
use File::Spec;
use File::Find;
use Cwd;

use vars qw(@ISA @EXPORT_OK $VERSION);
@ISA = qw(Exporter);
@EXPORT_OK = qw(&pod_find &simplify_name &pod_where &contains_pod);

# package global variables
my $SIMPLIFY_RX;

=head2 C<pod_find( { %opts } , @directories )>

The function B<pod_find> searches for POD documents in a given set of
files and/or directories. It returns a hash with the file names as keys
and the POD name as value. The POD name is derived from the file name
and its position in the directory tree.

E.g. when searching in F<$HOME/perl5lib>, the file
F<$HOME/perl5lib/MyModule.pm> would get the POD name I<MyModule>,
whereas F<$HOME/perl5lib/Myclass/Subclass.pm> would be
I<Myclass::Subclass>. The name information can be used for POD
translators.

Only text files containing at least one valid POD command are found.

A warning is printed if more than one POD file with the same POD name
is found, e.g. F<CPAN.pm> in different directories. This usually
indicates duplicate occurrences of modules in the I<@INC> search path.

B<OPTIONS> The first argument for B<pod_find> may be a hash reference
with options. The rest are either directories that are searched
recursively or files.  The POD names of files are the plain basenames
with any Perl-like extension (.pm, .pl, .pod) stripped.

=over 4

=item C<-verbose =E<gt> 1>

Print progress information while scanning.

=item C<-perl =E<gt> 1>

Apply Perl-specific heuristics to find the correct PODs. This includes
stripping Perl-like extensions, omitting subdirectories that are numeric
but do I<not> match the current Perl interpreter's version id, suppressing
F<site_perl> as a module hierarchy name etc.

=item C<-script =E<gt> 1>

Search for PODs in the current Perl interpreter's installation 
B<scriptdir>. This is taken from the local L<Config|Config> module.

=item C<-inc =E<gt> 1>

Search for PODs in the current Perl interpreter's I<@INC> paths. This
automatically considers paths specified in the C<PERL5LIB> environment
as this is prepended to I<@INC> by the Perl interpreter itself.

=back

=cut

# return a hash of the POD files found
# first argument may be a hashref (options),
# rest is a list of directories to search recursively
sub pod_find
{
    my %opts;
    if(ref $_[0]) {
        %opts = %{shift()};
    }

    $opts{-verbose} ||= 0;
    $opts{-perl}    ||= 0;

    my (@search) = @_;

    if($opts{-script}) {
        require Config;
        push(@search, $Config::Config{scriptdir});
        $opts{-perl} = 1;
    }

    if($opts{-inc}) {
        push(@search, grep($_ ne '.',@INC));
        $opts{-perl} = 1;
    }

    if($opts{-perl}) {
        require Config;
        # this code simplifies the POD name for Perl modules:
        # * remove "site_perl"
        # * remove e.g. "i586-linux" (from 'archname')
        # * remove e.g. 5.00503
        # * remove pod/ if followed by *.pod (e.g. in pod/perlfunc.pod)
        $SIMPLIFY_RX =
          qq!^(?i:site_perl/|\Q$Config::Config{archname}\E/|\\d+\\.\\d+([_.]?\\d+)?/|pod/(?=.*?\\.pod\\z))*!;

    }

    my %dirs_visited;
    my %pods;
    my %names;
    my $pwd = cwd();

    foreach my $try (@search) {
        unless(File::Spec->file_name_is_absolute($try)) {
            # make path absolute
            $try = File::Spec->catfile($pwd,$try);
        }
        # simplify path
        # on VMS canonpath will vmsify:[the.path], but File::Find::find
        # wants /unixy/paths
        $try = File::Spec->canonpath($try) if ($^O ne 'VMS');
        my $name;
        if(-f $try) {
            if($name = _check_and_extract_name($try, $opts{-verbose})) {
                _check_for_duplicates($try, $name, \%names, \%pods);
            }
            next;
        }
        my $root_rx = qq!^\Q$try\E/!;
        File::Find::find( sub {
            my $item = $File::Find::name;
            if(-d) {
                if($dirs_visited{$item}) {
                    warn "Directory '$item' already seen, skipping.\n"
                        if($opts{-verbose});
                    $File::Find::prune = 1;
                    return;
                }
                else {
                    $dirs_visited{$item} = 1;
                }
                if($opts{-perl} && /^(\d+\.[\d_]+)\z/s && eval "$1" != $]) {
                    $File::Find::prune = 1;
                    warn "Perl $] version mismatch on $_, skipping.\n"
                        if($opts{-verbose});
                }
                return;
            }
            if($name = _check_and_extract_name($item, $opts{-verbose}, $root_rx)) {
                _check_for_duplicates($item, $name, \%names, \%pods);
            }
        }, $try); # end of File::Find::find
    }
    chdir $pwd;
    %pods;
}

sub _check_for_duplicates {
    my ($file, $name, $names_ref, $pods_ref) = @_;
    if($$names_ref{$name}) {
        warn "Duplicate POD found (shadowing?): $name ($file)\n";
        warn "    Already seen in ",
            join(' ', grep($$pods_ref{$_} eq $name, keys %$pods_ref)),"\n";
    }
    else {
        $$names_ref{$name} = 1;
    }
    $$pods_ref{$file} = $name;
}

sub _check_and_extract_name {
    my ($file, $verbose, $root_rx) = @_;

    # check extension or executable flag
    # this involves testing the .bat extension on Win32!
    unless(-f $file && -T _ && ($file =~ /\.(pod|pm|plx?)\z/i || -x _ )) {
      return undef;
    }

    return undef unless contains_pod($file,$verbose);

    # strip non-significant path components
    # TODO what happens on e.g. Win32?
    my $name = $file;
    if(defined $root_rx) {
        $name =~ s!$root_rx!!s;
        $name =~ s!$SIMPLIFY_RX!!os if(defined $SIMPLIFY_RX);
    }
    else {
        $name =~ s:^.*/::s;
    }
    _simplify($name);
    $name =~ s!/+!::!g; #/
    $name;
}

=head2 C<simplify_name( $str )>

The function B<simplify_name> is equivalent to B<basename>, but also
strips Perl-like extensions (.pm, .pl, .pod) and extensions like
F<.bat>, F<.cmd> on Win32 and OS/2, or F<.com> on VMS, respectively.

=cut

# basic simplification of the POD name:
# basename & strip extension
sub simplify_name {
    my ($str) = @_;
    # remove all path components
    $str =~ s:^.*/::s;
    _simplify($str);
    $str;
}

# internal sub only
sub _simplify {
    # strip Perl's own extensions
    $_[0] =~ s/\.(pod|pm|plx?)\z//i;
    # strip meaningless extensions on Win32 and OS/2
    $_[0] =~ s/\.(bat|exe|cmd)\z//i if($^O =~ /win|os2/i);
    # strip meaningless extensions on VMS
    $_[0] =~ s/\.(com)\z//i if($^O eq 'VMS');
}

# contribution from Tim Jenness <t.jenness@jach.hawaii.edu>

=head2 C<pod_where( { %opts }, $pod )>

Returns the location of a pod document given a search directory
and a module (e.g. C<File::Find>) or script (e.g. C<perldoc>) name.

Options:

=over 4

=item C<-inc =E<gt> 1>

Search @INC for the pod and also the C<scriptdir> defined in the
L<Config|Config> module.

=item C<-dirs =E<gt> [ $dir1, $dir2, ... ]>

Reference to an array of search directories. These are searched in order
before looking in C<@INC> (if B<-inc>). Current directory is used if
none are specified.

=item C<-verbose =E<gt> 1>

List directories as they are searched

=back

Returns the full path of the first occurence to the file.
Package names (eg 'A::B') are automatically converted to directory
names in the selected directory. (eg on unix 'A::B' is converted to
'A/B'). Additionally, '.pm', '.pl' and '.pod' are appended to the
search automatically if required.

A subdirectory F<pod/> is also checked if it exists in any of the given
search directories. This ensures that e.g. L<perlfunc|perlfunc> is
found.

It is assumed that if a module name is supplied, that that name
matches the file name. Pods are not opened to check for the 'NAME'
entry.

A check is made to make sure that the file that is found does 
contain some pod documentation.

=cut

sub pod_where {

  # default options
  my %options = (
         '-inc' => 0,
         '-verbose' => 0,
         '-dirs' => [ '.' ],
        );

  # Check for an options hash as first argument
  if (defined $_[0] && ref($_[0]) eq 'HASH') {
    my $opt = shift;

    # Merge default options with supplied options
    %options = (%options, %$opt);
  }

  # Check usage
  carp 'Usage: pod_where({options}, $pod)' unless (scalar(@_));

  # Read argument
  my $pod = shift;

  # Split on :: and then join the name together using File::Spec
  my @parts = split (/::/, $pod);

  # Get full directory list
  my @search_dirs = @{ $options{'-dirs'} };

  if ($options{'-inc'}) {

    require Config;

    # Add @INC
    push (@search_dirs, @INC) if $options{'-inc'};

    # Add location of pod documentation for perl man pages (eg perlfunc)
    # This is a pod directory in the private install tree
    #my $perlpoddir = File::Spec->catdir($Config::Config{'installprivlib'},
    #					'pod');
    #push (@search_dirs, $perlpoddir)
    #  if -d $perlpoddir;

    # Add location of binaries such as pod2text
    push (@search_dirs, $Config::Config{'scriptdir'})
      if -d $Config::Config{'scriptdir'};
  }

  # Loop over directories
  Dir: foreach my $dir ( @search_dirs ) {

    # Don't bother if cant find the directory
    if (-d $dir) {
      warn "Looking in directory $dir\n" 
        if $options{'-verbose'};

      # Now concatenate this directory with the pod we are searching for
      my $fullname = File::Spec->catfile($dir, @parts);
      warn "Filename is now $fullname\n"
        if $options{'-verbose'};

      # Loop over possible extensions
      foreach my $ext ('', '.pod', '.pm', '.pl') {
        my $fullext = $fullname . $ext;
        if (-f $fullext && 
         contains_pod($fullext, $options{'-verbose'}) ) {
          warn "FOUND: $fullext\n" if $options{'-verbose'};
          return $fullext;
        }
      }
    } else {
      warn "Directory $dir does not exist\n"
        if $options{'-verbose'};
      next Dir;
    }
    if(-d File::Spec->catdir($dir,'pod')) {
      $dir = File::Spec->catdir($dir,'pod');
      redo Dir;
    }
  }
  # No match;
  return undef;
}

=head2 C<contains_pod( $file , $verbose )>

Returns true if the supplied filename (not POD module) contains some pod
information.

=cut

sub contains_pod {
  my $file = shift;
  my $verbose = 0;
  $verbose = shift if @_;

  # check for one line of POD
  unless(open(POD,"<$file")) {
    warn "Error: $file is unreadable: $!\n";
    return undef;
  }
  
  local $/ = undef;
  my $pod = <POD>;
  close(POD) || die "Error closing $file: $!\n";
  unless($pod =~ /\n=(head\d|pod|over|item)\b/s) {
    warn "No POD in $file, skipping.\n"
      if($verbose);
    return 0;
  }

  return 1;
}

=head1 AUTHOR

Marek Rouchal E<lt>marek@saftsack.fs.uni-bayreuth.deE<gt>,
heavily borrowing code from Nick Ing-Simmons' PodToHtml.

Tim Jenness E<lt>t.jenness@jach.hawaii.eduE<gt> provided
C<pod_where> and C<contains_pod>.

=head1 SEE ALSO

L<Pod::Parser>, L<Pod::Checker>, L<perldoc>

=cut

1;
Commit	Line	Data
e2c3adef GS	1	#############################################################################
	2	# Pod/Find.pm -- finds files containing POD documentation
	3	#
	4	# Author: Marek Rouchal <marek@saftsack.fs.uni-bayreuth.de>
	5	#
66aff6dd GS	6	# Copyright (C) 1999-2000 by Marek Rouchal (and borrowing code
66aff6dd GS	7	# from Nick Ing-Simmon's PodToHtml). All rights reserved.
e2c3adef GS	8	# This file is part of "PodParser". Pod::Find is free software;
	9	# you can redistribute it and/or modify it under the same terms
	10	# as Perl itself.
	11	#############################################################################
	12
	13	package Pod::Find;
	14
	15	use vars qw($VERSION);
92e3d63a JH	16	$VERSION = 0.21; ## Current version of this package
	17	require 5.005; ## requires this Perl version or later
	18	use Carp;
e2c3adef GS	19
	20	#############################################################################
	21
	22	=head1 NAME
	23
	24	Pod::Find - find POD documents in directory trees
	25
	26	=head1 SYNOPSIS
	27
	28	use Pod::Find qw(pod_find simplify_name);
	29	my %pods = pod_find({ -verbose => 1, -inc => 1 });
	30	foreach(keys %pods) {
	31	print "found library POD `$pods{$_}' in $_\n";
	32	}
	33
	34	print "podname=",simplify_name('a/b/c/mymodule.pod'),"\n";
	35
92e3d63a JH	36	$location = pod_where( { -inc => 1 }, "Pod::Find" );
92e3d63a JH	37
e2c3adef GS	38	=head1 DESCRIPTION
e2c3adef GS	39
92e3d63a JH	40	B<Pod::Find> provides a set of functions to locate POD files. Note that
	41	no function is exported by default to avoid pollution of your namespace,
	42	so be sure to specify them in the B<use> statement if you need them:
	43
	44	use Pod::Find qw(pod_find);
	45
	46	=cut
	47
	48	use strict;
	49	#use diagnostics;
	50	use Exporter;
	51	use File::Spec;
	52	use File::Find;
	53	use Cwd;
	54
	55	use vars qw(@ISA @EXPORT_OK $VERSION);
	56	@ISA = qw(Exporter);
	57	@EXPORT_OK = qw(&pod_find &simplify_name &pod_where &contains_pod);
	58
	59	# package global variables
	60	my $SIMPLIFY_RX;
	61
	62	=head2 C<pod_find( { %opts } , @directories )>
	63
	64	The function B<pod_find> searches for POD documents in a given set of
	65	files and/or directories. It returns a hash with the file names as keys
	66	and the POD name as value. The POD name is derived from the file name
	67	and its position in the directory tree.
e2c3adef GS	68
	69	E.g. when searching in F<$HOME/perl5lib>, the file
	70	F<$HOME/perl5lib/MyModule.pm> would get the POD name I<MyModule>,
	71	whereas F<$HOME/perl5lib/Myclass/Subclass.pm> would be
	72	I<Myclass::Subclass>. The name information can be used for POD
	73	translators.
	74
	75	Only text files containing at least one valid POD command are found.
	76
	77	A warning is printed if more than one POD file with the same POD name
	78	is found, e.g. F<CPAN.pm> in different directories. This usually
2773b013	79	indicates duplicate occurrences of modules in the I<@INC> search path.
e2c3adef	80
92e3d63a JH	81	B<OPTIONS> The first argument for B<pod_find> may be a hash reference
	82	with options. The rest are either directories that are searched
	83	recursively or files. The POD names of files are the plain basenames
	84	with any Perl-like extension (.pm, .pl, .pod) stripped.
e2c3adef GS	85
	86	=over 4
	87
92e3d63a	88	=item C<-verbose =E<gt> 1>
e2c3adef GS	89
	90	Print progress information while scanning.
	91
92e3d63a	92	=item C<-perl =E<gt> 1>
e2c3adef GS	93
	94	Apply Perl-specific heuristics to find the correct PODs. This includes
	95	stripping Perl-like extensions, omitting subdirectories that are numeric
	96	but do I<not> match the current Perl interpreter's version id, suppressing
	97	F<site_perl> as a module hierarchy name etc.
	98
92e3d63a	99	=item C<-script =E<gt> 1>
e2c3adef GS	100
	101	Search for PODs in the current Perl interpreter's installation
	102	B<scriptdir>. This is taken from the local L<Config\|Config> module.
	103
92e3d63a	104	=item C<-inc =E<gt> 1>
e2c3adef	105
2773b013	106	Search for PODs in the current Perl interpreter's I<@INC> paths. This
92e3d63a JH	107	automatically considers paths specified in the C<PERL5LIB> environment
92e3d63a JH	108	as this is prepended to I<@INC> by the Perl interpreter itself.
e2c3adef GS	109
	110	=back
	111
e2c3adef GS	112	=cut
e2c3adef GS	113
66aff6dd GS	114	# return a hash of the POD files found
	115	# first argument may be a hashref (options),
	116	# rest is a list of directories to search recursively
e2c3adef GS	117	sub pod_find
	118	{
	119	my %opts;
	120	if(ref $_[0]) {
	121	%opts = %{shift()};
	122	}
	123
	124	$opts{-verbose} \|\|= 0;
	125	$opts{-perl} \|\|= 0;
	126
	127	my (@search) = @_;
	128
	129	if($opts{-script}) {
	130	require Config;
	131	push(@search, $Config::Config{scriptdir});
	132	$opts{-perl} = 1;
	133	}
	134
	135	if($opts{-inc}) {
	136	push(@search, grep($_ ne '.',@INC));
	137	$opts{-perl} = 1;
	138	}
	139
	140	if($opts{-perl}) {
	141	require Config;
	142	# this code simplifies the POD name for Perl modules:
	143	# * remove "site_perl"
2773b013	144	# * remove e.g. "i586-linux" (from 'archname')
e2c3adef GS	145	# * remove e.g. 5.00503
	146	# * remove pod/ if followed by *.pod (e.g. in pod/perlfunc.pod)
	147	$SIMPLIFY_RX =
fe6f1558	148	qq!^(?i:site_perl/\|\Q$Config::Config{archname}\E/\|\\d+\\.\\d+([_.]?\\d+)?/\|pod/(?=.?\\.pod\\z))!;
66aff6dd	149
e2c3adef GS	150	}
	151
	152	my %dirs_visited;
	153	my %pods;
	154	my %names;
	155	my $pwd = cwd();
	156
	157	foreach my $try (@search) {
2773b013 GS	158	unless(File::Spec->file_name_is_absolute($try)) {
	159	# make path absolute
	160	$try = File::Spec->catfile($pwd,$try);
	161	}
	162	# simplify path
16be52b8 PP	163	# on VMS canonpath will vmsify:[the.path], but File::Find::find
	164	# wants /unixy/paths
	165	$try = File::Spec->canonpath($try) if ($^O ne 'VMS');
e2c3adef GS	166	my $name;
	167	if(-f $try) {
	168	if($name = _check_and_extract_name($try, $opts{-verbose})) {
	169	_check_for_duplicates($try, $name, \%names, \%pods);
	170	}
	171	next;
	172	}
2773b013	173	my $root_rx = qq!^\Q$try\E/!;
e2c3adef	174	File::Find::find( sub {
2773b013 GS	175	my $item = $File::Find::name;
	176	if(-d) {
	177	if($dirs_visited{$item}) {
	178	warn "Directory '$item' already seen, skipping.\n"
	179	if($opts{-verbose});
	180	$File::Find::prune = 1;
	181	return;
	182	}
	183	else {
	184	$dirs_visited{$item} = 1;
	185	}
	186	if($opts{-perl} && /^(\d+\.[\d_]+)\z/s && eval "$1" != $]) {
e2c3adef GS	187	$File::Find::prune = 1;
e2c3adef GS	188	warn "Perl $] version mismatch on $_, skipping.\n"
2773b013 GS	189	if($opts{-verbose});
	190	}
	191	return;
	192	}
e2c3adef GS	193	if($name = _check_and_extract_name($item, $opts{-verbose}, $root_rx)) {
	194	_check_for_duplicates($item, $name, \%names, \%pods);
	195	}
2773b013	196	}, $try); # end of File::Find::find
e2c3adef GS	197	}
	198	chdir $pwd;
	199	%pods;
	200	}
	201
	202	sub _check_for_duplicates {
	203	my ($file, $name, $names_ref, $pods_ref) = @_;
	204	if($$names_ref{$name}) {
	205	warn "Duplicate POD found (shadowing?): $name ($file)\n";
2773b013 GS	206	warn " Already seen in ",
2773b013 GS	207	join(' ', grep($$pods_ref{$_} eq $name, keys %$pods_ref)),"\n";
e2c3adef GS	208	}
	209	else {
	210	$$names_ref{$name} = 1;
	211	}
	212	$$pods_ref{$file} = $name;
	213	}
	214
	215	sub _check_and_extract_name {
	216	my ($file, $verbose, $root_rx) = @_;
	217
2773b013 GS	218	# check extension or executable flag
2773b013 GS	219	# this involves testing the .bat extension on Win32!
92e3d63a JH	220	unless(-f $file && -T _ && ($file =~ /\.(pod\|pm\|plx?)\z/i \|\| -x _ )) {
92e3d63a JH	221	return undef;
e2c3adef GS	222	}
e2c3adef GS	223
92e3d63a	224	return undef unless contains_pod($file,$verbose);
e2c3adef GS	225
e2c3adef GS	226	# strip non-significant path components
92e3d63a	227	# TODO what happens on e.g. Win32?
e2c3adef GS	228	my $name = $file;
e2c3adef GS	229	if(defined $root_rx) {
fe6f1558 GS	230	$name =~ s!$root_rx!!s;
fe6f1558 GS	231	$name =~ s!$SIMPLIFY_RX!!os if(defined $SIMPLIFY_RX);
e2c3adef GS	232	}
e2c3adef GS	233	else {
fe6f1558	234	$name =~ s:^.*/::s;
e2c3adef	235	}
2773b013 GS	236	_simplify($name);
2773b013 GS	237	$name =~ s!/+!::!g; #/
e2c3adef GS	238	$name;
	239	}
	240
92e3d63a JH	241	=head2 C<simplify_name( $str )>
	242
	243	The function B<simplify_name> is equivalent to B<basename>, but also
	244	strips Perl-like extensions (.pm, .pl, .pod) and extensions like
2eec1a1e	245	F<.bat>, F<.cmd> on Win32 and OS/2, or F<.com> on VMS, respectively.
92e3d63a JH	246
	247	=cut
	248
e2c3adef GS	249	# basic simplification of the POD name:
	250	# basename & strip extension
	251	sub simplify_name {
	252	my ($str) = @_;
2773b013	253	# remove all path components
fe6f1558	254	$str =~ s:^.*/::s;
2773b013	255	_simplify($str);
e2c3adef GS	256	$str;
	257	}
	258
2773b013 GS	259	# internal sub only
	260	sub _simplify {
	261	# strip Perl's own extensions
	262	$_[0] =~ s/\.(pod\|pm\|plx?)\z//i;
	263	# strip meaningless extensions on Win32 and OS/2
	264	$_[0] =~ s/\.(bat\|exe\|cmd)\z//i if($^O =~ /win\|os2/i);
2eec1a1e PP	265	# strip meaningless extensions on VMS
2eec1a1e PP	266	$_[0] =~ s/\.(com)\z//i if($^O eq 'VMS');
2773b013 GS	267	}
2773b013 GS	268
92e3d63a JH	269	# contribution from Tim Jenness <t.jenness@jach.hawaii.edu>
	270
	271	=head2 C<pod_where( { %opts }, $pod )>
	272
	273	Returns the location of a pod document given a search directory
	274	and a module (e.g. C<File::Find>) or script (e.g. C<perldoc>) name.
	275
	276	Options:
	277
	278	=over 4
	279
	280	=item C<-inc =E<gt> 1>
	281
	282	Search @INC for the pod and also the C<scriptdir> defined in the
	283	L<Config\|Config> module.
	284
	285	=item C<-dirs =E<gt> [ $dir1, $dir2, ... ]>
	286
	287	Reference to an array of search directories. These are searched in order
	288	before looking in C<@INC> (if B<-inc>). Current directory is used if
	289	none are specified.
	290
	291	=item C<-verbose =E<gt> 1>
	292
	293	List directories as they are searched
	294
	295	=back
	296
	297	Returns the full path of the first occurence to the file.
	298	Package names (eg 'A::B') are automatically converted to directory
	299	names in the selected directory. (eg on unix 'A::B' is converted to
	300	'A/B'). Additionally, '.pm', '.pl' and '.pod' are appended to the
	301	search automatically if required.
	302
	303	A subdirectory F<pod/> is also checked if it exists in any of the given
	304	search directories. This ensures that e.g. L<perlfunc\|perlfunc> is
	305	found.
	306
	307	It is assumed that if a module name is supplied, that that name
	308	matches the file name. Pods are not opened to check for the 'NAME'
	309	entry.
	310
	311	A check is made to make sure that the file that is found does
	312	contain some pod documentation.
	313
	314	=cut
	315
	316	sub pod_where {
	317
	318	# default options
	319	my %options = (
	320	'-inc' => 0,
	321	'-verbose' => 0,
	322	'-dirs' => [ '.' ],
	323	);
	324
	325	# Check for an options hash as first argument
	326	if (defined $_[0] && ref($_[0]) eq 'HASH') {
	327	my $opt = shift;
	328
	329	# Merge default options with supplied options
	330	%options = (%options, %$opt);
	331	}
	332
333	# Check usage
334	carp 'Usage: pod_where({options}, $pod)' unless (scalar(@_));
335
336	# Read argument
337	my $pod = shift;
338
339	# Split on :: and then join the name together using File::Spec
340	my @parts = split (/::/, $pod);
341
342	# Get full directory list
343	my @search_dirs = @{ $options{'-dirs'} };
344
345	if ($options{'-inc'}) {
346
347	require Config;
348
349	# Add @INC
350	push (@search_dirs, @INC) if $options{'-inc'};
351
352	# Add location of pod documentation for perl man pages (eg perlfunc)
353	# This is a pod directory in the private install tree
354	#my $perlpoddir = File::Spec->catdir($Config::Config{'installprivlib'},
355	# 'pod');
356	#push (@search_dirs, $perlpoddir)
357	# if -d $perlpoddir;
358
359	# Add location of binaries such as pod2text
360	push (@search_dirs, $Config::Config{'scriptdir'})
361	if -d $Config::Config{'scriptdir'};
362	}
363
364	# Loop over directories
365	Dir: foreach my $dir ( @search_dirs ) {
366
367	# Don't bother if cant find the directory
368	if (-d $dir) {
369	warn "Looking in directory $dir\n"
370	if $options{'-verbose'};
371
372	# Now concatenate this directory with the pod we are searching for
373	my $fullname = File::Spec->catfile($dir, @parts);
374	warn "Filename is now $fullname\n"
375	if $options{'-verbose'};
376
377	# Loop over possible extensions
378	foreach my $ext ('', '.pod', '.pm', '.pl') {
379	my $fullext = $fullname . $ext;
380	if (-f $fullext &&
381	contains_pod($fullext, $options{'-verbose'}) ) {
382	warn "FOUND: $fullext\n" if $options{'-verbose'};
383	return $fullext;
384	}
385	}
386	} else {
387	warn "Directory $dir does not exist\n"
388	if $options{'-verbose'};
389	next Dir;
390	}
391	if(-d File::Spec->catdir($dir,'pod')) {
392	$dir = File::Spec->catdir($dir,'pod');
393	redo Dir;
394	}
395	}
396	# No match;
397	return undef;
398	}
399
400	=head2 C<contains_pod( $file , $verbose )>
401
402	Returns true if the supplied filename (not POD module) contains some pod
403	information.
404
405	=cut
406
407	sub contains_pod {
408	my $file = shift;
409	my $verbose = 0;
410	$verbose = shift if @_;
411
412	# check for one line of POD
413	unless(open(POD,"<$file")) {
414	warn "Error: $file is unreadable: $!\n";
415	return undef;
416	}
417
418	local $/ = undef;
419	my $pod = <POD>;
420	close(POD) \|\| die "Error closing $file: $!\n";
421	unless($pod =~ /\n=(head\d\|pod\|over\|item)\b/s) {
422	warn "No POD in $file, skipping.\n"
423	if($verbose);
424	return 0;
425	}
426
427	return 1;
428	}
429
430	=head1 AUTHOR
431
432	Marek Rouchal E<lt>marek@saftsack.fs.uni-bayreuth.deE<gt>,
433	heavily borrowing code from Nick Ing-Simmons' PodToHtml.
434
435	Tim Jenness E<lt>t.jenness@jach.hawaii.eduE<gt> provided
436	C<pod_where> and C<contains_pod>.
437
438	=head1 SEE ALSO
439
440	L<Pod::Parser>, L<Pod::Checker>, L<perldoc>
441
442	=cut
443
e2c3adef GS	444	1;
e2c3adef GS	445