lib/perl5/5.6.1/msys/IO/Dir.pm

   1 # IO::Dir.pm
   2 #
   3 # Copyright (c) 1997-8 Graham Barr <gbarr@pobox.com>. All rights reserved.
   4 # This program is free software; you can redistribute it and/or
   5 # modify it under the same terms as Perl itself.
   6
   7 package IO::Dir;
   8
   9 use 5.6.0;
  10
  11 use strict;
  12 use Carp;
  13 use Symbol;
  14 use Exporter;
  15 use IO::File;
  16 our(@ISA, $VERSION, @EXPORT_OK);
  17 use Tie::Hash;
  18 use File::stat;
  19 use File::Spec;
  20
  21 @ISA = qw(Tie::Hash Exporter);
  22 $VERSION = "1.03";
  23 @EXPORT_OK = qw(DIR_UNLINK);
  24
  25 sub DIR_UNLINK () { 1 }
  26
  27 sub new {
  28     @_ >= 1 && @_ <= 2 or croak 'usage: new IO::Dir [DIRNAME]';
  29     my $class = shift;
  30     my $dh = gensym;
  31     if (@_) {
  32         IO::Dir::open($dh, $_[0])
  33             or return undef;
  34     }
  35     bless $dh, $class;
  36 }
  37
  38 sub DESTROY {
  39     my ($dh) = @_;
  40     closedir($dh);
  41 }
  42
  43 sub open {
  44     @_ == 2 or croak 'usage: $dh->open(DIRNAME)';
  45     my ($dh, $dirname) = @_;
  46     return undef
  47         unless opendir($dh, $dirname);
  48     # a dir name should always have a ":" in it; assume dirname is
  49     # in current directory
  50     $dirname = ':' .  $dirname if ( ($^O eq 'MacOS') && ($dirname =~ /^[^:]+$/) );
  51     ${*$dh}{io_dir_path} = $dirname;
  52     1;
  53 }
  54
  55 sub close {
  56     @_ == 1 or croak 'usage: $dh->close()';
  57     my ($dh) = @_;
  58     closedir($dh);
  59 }
  60
  61 sub read {
  62     @_ == 1 or croak 'usage: $dh->read()';
  63     my ($dh) = @_;
  64     readdir($dh);
  65 }
  66
  67 sub seek {
  68     @_ == 2 or croak 'usage: $dh->seek(POS)';
  69     my ($dh,$pos) = @_;
  70     seekdir($dh,$pos);
  71 }
  72
  73 sub tell {
  74     @_ == 1 or croak 'usage: $dh->tell()';
  75     my ($dh) = @_;
  76     telldir($dh);
  77 }
  78
  79 sub rewind {
  80     @_ == 1 or croak 'usage: $dh->rewind()';
  81     my ($dh) = @_;
  82     rewinddir($dh);
  83 }
  84
  85 sub TIEHASH {
  86     my($class,$dir,$options) = @_;
  87
  88     my $dh = $class->new($dir)
  89         or return undef;
  90
  91     $options ||= 0;
  92
  93     ${*$dh}{io_dir_unlink} = $options & DIR_UNLINK;
  94     $dh;
  95 }
  96
  97 sub FIRSTKEY {
  98     my($dh) = @_;
  99     $dh->rewind;
 100     scalar $dh->read;
 101 }
 102
 103 sub NEXTKEY {
 104     my($dh) = @_;
 105     scalar $dh->read;
 106 }
 107
 108 sub EXISTS {
 109     my($dh,$key) = @_;
 110     -e File::Spec->catfile(${*$dh}{io_dir_path}, $key);
 111 }
 112
 113 sub FETCH {
 114     my($dh,$key) = @_;
 115     &lstat(File::Spec->catfile(${*$dh}{io_dir_path}, $key));
 116 }
 117
 118 sub STORE {
 119     my($dh,$key,$data) = @_;
 120     my($atime,$mtime) = ref($data) ? @$data : ($data,$data);
 121     my $file = File::Spec->catfile(${*$dh}{io_dir_path}, $key);
 122     unless(-e $file) {
 123         my $io = IO::File->new($file,O_CREAT | O_RDWR);
 124         $io->close if $io;
 125     }
 126     utime($atime,$mtime, $file);
 127 }
 128
 129 sub DELETE {
 130     my($dh,$key) = @_;
 131     # Only unlink if unlink-ing is enabled
 132     my $file = File::Spec->catfile(${*$dh}{io_dir_path}, $key);
 133
 134     return 0
 135         unless ${*$dh}{io_dir_unlink};
 136
 137     -d $file
 138         ? rmdir($file)
 139         : unlink($file);
 140 }
 141
 142 1;
 143
 144 __END__
 145
 146 =head1 NAME
 147
 148 IO::Dir - supply object methods for directory handles
 149
 150 =head1 SYNOPSIS
 151
 152     use IO::Dir;
 153     $d = new IO::Dir ".";
 154     if (defined $d) {
 155         while (defined($_ = $d->read)) { something($_); }
 156         $d->rewind;
 157         while (defined($_ = $d->read)) { something_else($_); }
 158         undef $d;
 159     }
 160
 161     tie %dir, IO::Dir, ".";
 162     foreach (keys %dir) {
 163         print $_, " " , $dir{$_}->size,"\n";
 164     }
 165
 166 =head1 DESCRIPTION
 167
 168 The C<IO::Dir> package provides two interfaces to perl's directory reading
 169 routines.
 170
 171 The first interface is an object approach. C<IO::Dir> provides an object
 172 constructor and methods, which are just wrappers around perl's built in
 173 directory reading routines.
 174
 175 =over 4
 176
 177 =item new ( [ DIRNAME ] )
 178
 179 C<new> is the constuctor for C<IO::Dir> objects. It accepts one optional
 180 argument which,  if given, C<new> will pass to C<open>
 181
 182 =back
 183
 184 The following methods are wrappers for the directory related functions built
 185 into perl (the trailing `dir' has been removed from the names). See L<perlfunc>
 186 for details of these functions.
 187
 188 =over 4
 189
 190 =item open ( DIRNAME )
 191
 192 =item read ()
 193
 194 =item seek ( POS )
 195
 196 =item tell ()
 197
 198 =item rewind ()
 199
 200 =item close ()
 201
 202 =back
 203
 204 C<IO::Dir> also provides a interface to reading directories via a tied
 205 HASH. The tied HASH extends the interface beyond just the directory
 206 reading routines by the use of C<lstat>, from the C<File::stat> package,
 207 C<unlink>, C<rmdir> and C<utime>.
 208
 209 =over 4
 210
 211 =item tie %hash, IO::Dir, DIRNAME [, OPTIONS ]
 212
 213 =back
 214
 215 The keys of the HASH will be the names of the entries in the directory.
 216 Reading a value from the hash will be the result of calling
 217 C<File::stat::lstat>. Deleting an element from the hash will call C<unlink>
 218 providing that C<DIR_UNLINK> is passed in the C<OPTIONS>.
 219
 220 Assigning to an entry in the HASH will cause the time stamps of the file
 221 to be modified. If the file does not exist then it will be created. Assigning
 222 a single integer to a HASH element will cause both the access and
 223 modification times to be changed to that value. Alternatively a reference to
 224 an array of two values can be passed. The first array element will be used to
 225 set the access time and the second element will be used to set the modification
 226 time.
 227
 228 =head1 SEE ALSO
 229
 230 L<File::stat>
 231
 232 =head1 AUTHOR
 233
 234 Graham Barr. Currently maintained by the Perl Porters.  Please report all
 235 bugs to <perl5-porters@perl.org>.
 236
 237 =head1 COPYRIGHT
 238
 239 Copyright (c) 1997-8 Graham Barr <gbarr@pobox.com>. All rights reserved.
 240 This program is free software; you can redistribute it and/or
 241 modify it under the same terms as Perl itself.
 242
 243 =cut