[p5sagit/p5-mst-13.2.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, 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);
}

# 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	1	#############################################################################
	2	# Pod/Find.pm -- finds files containing POD documentation
	3	#
	4	# Author: Marek Rouchal <marek@saftsack.fs.uni-bayreuth.de>
	5	#
66aff6dd	6	# Copyright (C) 1999-2000 by Marek Rouchal (and borrowing code
66aff6dd	7	# from Nick Ing-Simmon's PodToHtml). All rights reserved.
e2c3adef	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);
22d4bb9c	16	$VERSION = 0.21; ## Current version of this package
	17	require 5.005; ## requires this Perl version or later
	18	use Carp;
e2c3adef	19
	20	#############################################################################
	21
	22	=head1 NAME
	23
	24	Pod::Find - find POD documents in directory trees
	25
	26	=head1 SYNOPSIS
	27
	28	use Pod::Find qw(pod_find simplify_name);
	29	my %pods = pod_find({ -verbose => 1, -inc => 1 });
	30	foreach(keys %pods) {
	31	print "found library POD `$pods{$_}' in $_\n";
	32	}
	33
	34	print "podname=",simplify_name('a/b/c/mymodule.pod'),"\n";
	35
22d4bb9c	36	$location = pod_where( { -inc => 1 }, "Pod::Find" );
22d4bb9c	37
e2c3adef	38	=head1 DESCRIPTION
e2c3adef	39
22d4bb9c	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 $SIMPLIFY_RX;
	61
	62	=head2 C<pod_find( { %opts } , @directories )>
	63
	64	The function B<pod_find> searches for POD documents in a given set of
	65	files and/or directories. It returns a hash with the file names as keys
	66	and the POD name as value. The POD name is derived from the file name
	67	and its position in the directory tree.
e2c3adef	68
	69	E.g. when searching in F<$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
ee8c7f54	79	indicates duplicate occurrences of modules in the I<@INC> search path.
e2c3adef	80
22d4bb9c	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	85
	86	=over 4
	87
22d4bb9c	88	=item C<-verbose =E<gt> 1>
e2c3adef	89
	90	Print progress information while scanning.
	91
22d4bb9c	92	=item C<-perl =E<gt> 1>
e2c3adef	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
22d4bb9c	99	=item C<-script =E<gt> 1>
e2c3adef	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
22d4bb9c	104	=item C<-inc =E<gt> 1>
e2c3adef	105
ee8c7f54	106	Search for PODs in the current Perl interpreter's I<@INC> paths. This
22d4bb9c	107	automatically considers paths specified in the C<PERL5LIB> environment
22d4bb9c	108	as this is prepended to I<@INC> by the Perl interpreter itself.
e2c3adef	109
	110	=back
	111
e2c3adef	112	=cut
e2c3adef	113
66aff6dd	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	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"
ee8c7f54	144	# * remove e.g. "i586-linux" (from 'archname')
e2c3adef	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	150	}
	151
	152	my %dirs_visited;
	153	my %pods;
	154	my %names;
	155	my $pwd = cwd();
	156
	157	foreach my $try (@search) {
ee8c7f54	158	unless(File::Spec->file_name_is_absolute($try)) {
	159	# make path absolute
	160	$try = File::Spec->catfile($pwd,$try);
	161	}
	162	# simplify path
22d4bb9c	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	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	}
ee8c7f54	173	my $root_rx = qq!^\Q$try\E/!;
e2c3adef	174	File::Find::find( sub {
ee8c7f54	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	187	$File::Find::prune = 1;
e2c3adef	188	warn "Perl $] version mismatch on $_, skipping.\n"
ee8c7f54	189	if($opts{-verbose});
	190	}
	191	return;
	192	}
e2c3adef	193	if($name = _check_and_extract_name($item, $opts{-verbose}, $root_rx)) {
	194	_check_for_duplicates($item, $name, \%names, \%pods);
	195	}
ee8c7f54	196	}, $try); # end of File::Find::find
e2c3adef	197	}
	198	chdir $pwd;
	199	%pods;
	200	}
	201
	202	sub _check_for_duplicates {
	203	my ($file, $name, $names_ref, $pods_ref) = @_;
	204	if($$names_ref{$name}) {
	205	warn "Duplicate POD found (shadowing?): $name ($file)\n";
ee8c7f54	206	warn " Already seen in ",
ee8c7f54	207	join(' ', grep($$pods_ref{$_} eq $name, keys %$pods_ref)),"\n";
e2c3adef	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
ee8c7f54	218	# check extension or executable flag
ee8c7f54	219	# this involves testing the .bat extension on Win32!
22d4bb9c	220	unless(-f $file && -T _ && ($file =~ /\.(pod\|pm\|plx?)\z/i \|\| -x _ )) {
22d4bb9c	221	return undef;
e2c3adef	222	}
e2c3adef	223
22d4bb9c	224	return undef unless contains_pod($file,$verbose);
e2c3adef	225
e2c3adef	226	# strip non-significant path components
22d4bb9c	227	# TODO what happens on e.g. Win32?
e2c3adef	228	my $name = $file;
e2c3adef	229	if(defined $root_rx) {
fe6f1558	230	$name =~ s!$root_rx!!s;
fe6f1558	231	$name =~ s!$SIMPLIFY_RX!!os if(defined $SIMPLIFY_RX);
e2c3adef	232	}
e2c3adef	233	else {
fe6f1558	234	$name =~ s:^.*/::s;
e2c3adef	235	}
ee8c7f54	236	_simplify($name);
ee8c7f54	237	$name =~ s!/+!::!g; #/
e2c3adef	238	$name;
	239	}
	240
22d4bb9c	241	=head2 C<simplify_name( $str )>
	242
	243	The function B<simplify_name> is equivalent to B<basename>, but also
	244	strips Perl-like extensions (.pm, .pl, .pod) and extensions like
	245	F<.bat>, F<.cmd> on Win32 and OS/2, respectively.
	246
	247	=cut
	248
e2c3adef	249	# basic simplification of the POD name:
	250	# basename & strip extension
	251	sub simplify_name {
	252	my ($str) = @_;
ee8c7f54	253	# remove all path components
fe6f1558	254	$str =~ s:^.*/::s;
ee8c7f54	255	_simplify($str);
e2c3adef	256	$str;
	257	}
	258
ee8c7f54	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);
	265	}
	266
22d4bb9c	267	# contribution from Tim Jenness <t.jenness@jach.hawaii.edu>
	268
	269	=head2 C<pod_where( { %opts }, $pod )>
	270
	271	Returns the location of a pod document given a search directory
	272	and a module (e.g. C<File::Find>) or script (e.g. C<perldoc>) name.
	273
	274	Options:
	275
	276	=over 4
	277
	278	=item C<-inc =E<gt> 1>
	279
	280	Search @INC for the pod and also the C<scriptdir> defined in the
	281	L<Config\|Config> module.
	282
	283	=item C<-dirs =E<gt> [ $dir1, $dir2, ... ]>
	284
	285	Reference to an array of search directories. These are searched in order
	286	before looking in C<@INC> (if B<-inc>). Current directory is used if
	287	none are specified.
	288
	289	=item C<-verbose =E<gt> 1>
	290
	291	List directories as they are searched
	292
	293	=back
	294
	295	Returns the full path of the first occurence to the file.
	296	Package names (eg 'A::B') are automatically converted to directory
	297	names in the selected directory. (eg on unix 'A::B' is converted to
	298	'A/B'). Additionally, '.pm', '.pl' and '.pod' are appended to the
	299	search automatically if required.
	300
	301	A subdirectory F<pod/> is also checked if it exists in any of the given
	302	search directories. This ensures that e.g. L<perlfunc\|perlfunc> is
	303	found.
	304
	305	It is assumed that if a module name is supplied, that that name
	306	matches the file name. Pods are not opened to check for the 'NAME'
	307	entry.
	308
	309	A check is made to make sure that the file that is found does
	310	contain some pod documentation.
	311
	312	=cut
	313
	314	sub pod_where {
	315
	316	# default options
	317	my %options = (
	318	'-inc' => 0,
	319	'-verbose' => 0,
	320	'-dirs' => [ '.' ],
	321	);
	322
	323	# Check for an options hash as first argument
	324	if (defined $_[0] && ref($_[0]) eq 'HASH') {
	325	my $opt = shift;
	326
	327	# Merge default options with supplied options
	328	%options = (%options, %$opt);
	329	}
	330
331	# Check usage
332	carp 'Usage: pod_where({options}, $pod)' unless (scalar(@_));
333
334	# Read argument
335	my $pod = shift;
336
337	# Split on :: and then join the name together using File::Spec
338	my @parts = split (/::/, $pod);
339
340	# Get full directory list
341	my @search_dirs = @{ $options{'-dirs'} };
342
343	if ($options{'-inc'}) {
344
345	require Config;
346
347	# Add @INC
348	push (@search_dirs, @INC) if $options{'-inc'};
349
350	# Add location of pod documentation for perl man pages (eg perlfunc)
351	# This is a pod directory in the private install tree
352	#my $perlpoddir = File::Spec->catdir($Config::Config{'installprivlib'},
353	# 'pod');
354	#push (@search_dirs, $perlpoddir)
355	# if -d $perlpoddir;
356
357	# Add location of binaries such as pod2text
358	push (@search_dirs, $Config::Config{'scriptdir'})
359	if -d $Config::Config{'scriptdir'};
360	}
361
362	# Loop over directories
363	Dir: foreach my $dir ( @search_dirs ) {
364
365	# Don't bother if cant find the directory
366	if (-d $dir) {
367	warn "Looking in directory $dir\n"
368	if $options{'-verbose'};
369
370	# Now concatenate this directory with the pod we are searching for
371	my $fullname = File::Spec->catfile($dir, @parts);
372	warn "Filename is now $fullname\n"
373	if $options{'-verbose'};
374
375	# Loop over possible extensions
376	foreach my $ext ('', '.pod', '.pm', '.pl') {
377	my $fullext = $fullname . $ext;
378	if (-f $fullext &&
379	contains_pod($fullext, $options{'-verbose'}) ) {
380	warn "FOUND: $fullext\n" if $options{'-verbose'};
381	return $fullext;
382	}
383	}
384	} else {
385	warn "Directory $dir does not exist\n"
386	if $options{'-verbose'};
387	next Dir;
388	}
389	if(-d File::Spec->catdir($dir,'pod')) {
390	$dir = File::Spec->catdir($dir,'pod');
391	redo Dir;
392	}
393	}
394	# No match;
395	return undef;
396	}
397
398	=head2 C<contains_pod( $file , $verbose )>
399
400	Returns true if the supplied filename (not POD module) contains some pod
401	information.
402
403	=cut
404
405	sub contains_pod {
406	my $file = shift;
407	my $verbose = 0;
408	$verbose = shift if @_;
409
410	# check for one line of POD
411	unless(open(POD,"<$file")) {
412	warn "Error: $file is unreadable: $!\n";
413	return undef;
414	}
415
416	local $/ = undef;
417	my $pod = <POD>;
418	close(POD) \|\| die "Error closing $file: $!\n";
419	unless($pod =~ /\n=(head\d\|pod\|over\|item)\b/s) {
420	warn "No POD in $file, skipping.\n"
421	if($verbose);
422	return 0;
423	}
424
425	return 1;
426	}
427
428	=head1 AUTHOR
429
430	Marek Rouchal E<lt>marek@saftsack.fs.uni-bayreuth.deE<gt>,
431	heavily borrowing code from Nick Ing-Simmons' PodToHtml.
432
433	Tim Jenness E<lt>t.jenness@jach.hawaii.eduE<gt> provided
434	C<pod_where> and C<contains_pod>.
435
436	=head1 SEE ALSO
437
438	L<Pod::Parser>, L<Pod::Checker>, L<perldoc>
439
440	=cut
441
e2c3adef	442	1;
e2c3adef	443