lib/perl5/5.6.1/User/grent.pm

   1 package User::grent;
   2 use strict;
   3
   4 use 5.005_64;
   5 our(@EXPORT, @EXPORT_OK, %EXPORT_TAGS);
   6 BEGIN {
   7     use Exporter   ();
   8     @EXPORT      = qw(getgrent getgrgid getgrnam getgr);
   9     @EXPORT_OK   = qw($gr_name $gr_gid $gr_passwd $gr_mem @gr_members);
  10     %EXPORT_TAGS = ( FIELDS => [ @EXPORT_OK, @EXPORT ] );
  11 }
  12 use vars      @EXPORT_OK;
  13
  14 # Class::Struct forbids use of @ISA
  15 sub import { goto &Exporter::import }
  16
  17 use Class::Struct qw(struct);
  18 struct 'User::grent' => [
  19     name    => '$',
  20     passwd  => '$',
  21     gid     => '$',
  22     members => '@',
  23 ];
  24
  25 sub populate (@) {
  26     return unless @_;
  27     my $gob = new();
  28     ($gr_name, $gr_passwd, $gr_gid) = @$gob[0,1,2] = @_[0,1,2];
  29     @gr_members = @{$gob->[3]} = split ' ', $_[3];
  30     return $gob;
  31 }
  32
  33 sub getgrent ( ) { populate(CORE::getgrent()) }
  34 sub getgrnam ($) { populate(CORE::getgrnam(shift)) }
  35 sub getgrgid ($) { populate(CORE::getgrgid(shift)) }
  36 sub getgr    ($) { ($_[0] =~ /^\d+/) ? &getgrgid : &getgrnam }
  37
  38 1;
  39 __END__
  40
  41 =head1 NAME
  42
  43 User::grent - by-name interface to Perl's built-in getgr*() functions
  44
  45 =head1 SYNOPSIS
  46
  47  use User::grent;
  48  $gr = getgrgid(0) or die "No group zero";
  49  if ( $gr->name eq 'wheel' && @{$gr->members} > 1 ) {
  50      print "gid zero name wheel, with other members";
  51  }
  52
  53  use User::grent qw(:FIELDS;
  54  getgrgid(0) or die "No group zero";
  55  if ( $gr_name eq 'wheel' && @gr_members > 1 ) {
  56      print "gid zero name wheel, with other members";
  57  }
  58
  59  $gr = getgr($whoever);
  60
  61 =head1 DESCRIPTION
  62
  63 This module's default exports override the core getgrent(), getgruid(),
  64 and getgrnam() functions, replacing them with versions that return
  65 "User::grent" objects.  This object has methods that return the similarly
  66 named structure field name from the C's passwd structure from F<grp.h>;
  67 namely name, passwd, gid, and members (not mem).  The first three
  68 return scalars, the last an array reference.
  69
  70 You may also import all the structure fields directly into your namespace
  71 as regular variables using the :FIELDS import tag.  (Note that this still
  72 overrides your core functions.)  Access these fields as variables named
  73 with a preceding C<gr_>.  Thus, C<$group_obj-E<gt>gid()> corresponds
  74 to $gr_gid if you import the fields.  Array references are available as
  75 regular array variables, so C<@{ $group_obj-E<gt>members() }> would be
  76 simply @gr_members.
  77
  78 The getpw() function is a simple front-end that forwards
  79 a numeric argument to getpwuid() and the rest to getpwnam().
  80
  81 To access this functionality without the core overrides,
  82 pass the C<use> an empty import list, and then access
  83 function functions with their full qualified names.
  84 On the other hand, the built-ins are still available
  85 via the C<CORE::> pseudo-package.
  86
  87 =head1 NOTE
  88
  89 While this class is currently implemented using the Class::Struct
  90 module to build a struct-like class, you shouldn't rely upon this.
  91
  92 =head1 AUTHOR
  93
  94 Tom Christiansen