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   1  =head1 NAME
   2  
   3  File::Basename - Parse file paths into directory, filename and suffix.
   4  
   5  =head1 SYNOPSIS
   6  
   7      use File::Basename;
   8  
   9      ($name,$path,$suffix) = fileparse($fullname,@suffixlist);
  10      $name = fileparse($fullname,@suffixlist);
  11  
  12      $basename = basename($fullname,@suffixlist);
  13      $dirname  = dirname($fullname);
  14  
  15  
  16  =head1 DESCRIPTION
  17  
  18  These routines allow you to parse file paths into their directory, filename
  19  and suffix.
  20  
  21  B<NOTE>: C<dirname()> and C<basename()> emulate the behaviours, and
  22  quirks, of the shell and C functions of the same name.  See each
  23  function's documentation for details.  If your concern is just parsing
  24  paths it is safer to use L<File::Spec>'s C<splitpath()> and
  25  C<splitdir()> methods.
  26  
  27  It is guaranteed that
  28  
  29      # Where $path_separator is / for Unix, \ for Windows, etc...
  30      dirname($path) . $path_separator . basename($path);
  31  
  32  is equivalent to the original path for all systems but VMS.
  33  
  34  
  35  =cut
  36  
  37  
  38  package File::Basename;
  39  
  40  # A bit of juggling to insure that C<use re 'taint';> always works, since
  41  # File::Basename is used during the Perl build, when the re extension may
  42  # not be available.
  43  BEGIN {
  44    unless (eval { require re; })
  45      { eval ' sub re::import { $^H |= 0x00100000; } ' } # HINT_RE_TAINT
  46    import re 'taint';
  47  }
  48  
  49  
  50  use strict;
  51  use 5.006;
  52  use warnings;
  53  our(@ISA, @EXPORT, $VERSION, $Fileparse_fstype, $Fileparse_igncase);
  54  require Exporter;
  55  @ISA = qw(Exporter);
  56  @EXPORT = qw(fileparse fileparse_set_fstype basename dirname);
  57  $VERSION = "2.76";
  58  
  59  fileparse_set_fstype($^O);
  60  
  61  
  62  =over 4
  63  
  64  =item C<fileparse>
  65  X<fileparse>
  66  
  67      my($filename, $directories, $suffix) = fileparse($path);
  68      my($filename, $directories, $suffix) = fileparse($path, @suffixes);
  69      my $filename                         = fileparse($path, @suffixes);
  70  
  71  The C<fileparse()> routine divides a file path into its $directories, $filename
  72  and (optionally) the filename $suffix.
  73  
  74  $directories contains everything up to and including the last
  75  directory separator in the $path including the volume (if applicable).
  76  The remainder of the $path is the $filename.
  77  
  78       # On Unix returns ("baz", "/foo/bar/", "")
  79       fileparse("/foo/bar/baz");
  80  
  81       # On Windows returns ("baz", "C:\foo\bar\", "")
  82       fileparse("C:\foo\bar\baz");
  83  
  84       # On Unix returns ("", "/foo/bar/baz/", "")
  85       fileparse("/foo/bar/baz/");
  86  
  87  If @suffixes are given each element is a pattern (either a string or a
  88  C<qr//>) matched against the end of the $filename.  The matching
  89  portion is removed and becomes the $suffix.
  90  
  91       # On Unix returns ("baz", "/foo/bar", ".txt")
  92       fileparse("/foo/bar/baz.txt", qr/\.[^.]*/);
  93  
  94  If type is non-Unix (see C<fileparse_set_fstype()>) then the pattern
  95  matching for suffix removal is performed case-insensitively, since
  96  those systems are not case-sensitive when opening existing files.
  97  
  98  You are guaranteed that C<$directories . $filename . $suffix> will
  99  denote the same location as the original $path.
 100  
 101  =cut
 102  
 103  
 104  sub fileparse {
 105    my($fullname,@suffices) = @_;
 106  
 107    unless (defined $fullname) {
 108        require Carp;
 109        Carp::croak("fileparse(): need a valid pathname");
 110    }
 111  
 112    my $orig_type = '';
 113    my($type,$igncase) = ($Fileparse_fstype, $Fileparse_igncase);
 114  
 115    my($taint) = substr($fullname,0,0);  # Is $fullname tainted?
 116  
 117    if ($type eq "VMS" and $fullname =~ m{/} ) {
 118      # We're doing Unix emulation
 119      $orig_type = $type;
 120      $type = 'Unix';
 121    }
 122  
 123    my($dirpath, $basename);
 124  
 125    if (grep { $type eq $_ } qw(MSDOS DOS MSWin32 Epoc)) {
 126      ($dirpath,$basename) = ($fullname =~ /^((?:.*[:\\\/])?)(.*)/s);
 127      $dirpath .= '.\\' unless $dirpath =~ /[\\\/]\z/;
 128    }
 129    elsif ($type eq "OS2") {
 130      ($dirpath,$basename) = ($fullname =~ m#^((?:.*[:\\/])?)(.*)#s);
 131      $dirpath = './' unless $dirpath;    # Can't be 0
 132      $dirpath .= '/' unless $dirpath =~ m#[\\/]\z#;
 133    }
 134    elsif ($type eq "MacOS") {
 135      ($dirpath,$basename) = ($fullname =~ /^(.*:)?(.*)/s);
 136      $dirpath = ':' unless $dirpath;
 137    }
 138    elsif ($type eq "AmigaOS") {
 139      ($dirpath,$basename) = ($fullname =~ /(.*[:\/])?(.*)/s);
 140      $dirpath = './' unless $dirpath;
 141    }
 142    elsif ($type eq 'VMS' ) {
 143      ($dirpath,$basename) = ($fullname =~ /^(.*[:>\]])?(.*)/s);
 144      $dirpath ||= '';  # should always be defined
 145    }
 146    else { # Default to Unix semantics.
 147      ($dirpath,$basename) = ($fullname =~ m{^(.*/)?(.*)}s);
 148      if ($orig_type eq 'VMS' and $fullname =~ m{^(/[^/]+/000000(/|$))(.*)}) {
 149        # dev:[000000] is top of VMS tree, similar to Unix '/'
 150        # so strip it off and treat the rest as "normal"
 151        my $devspec  = $1;
 152        my $remainder = $3;
 153        ($dirpath,$basename) = ($remainder =~ m{^(.*/)?(.*)}s);
 154        $dirpath ||= '';  # should always be defined
 155        $dirpath = $devspec.$dirpath;
 156      }
 157      $dirpath = './' unless $dirpath;
 158    }
 159        
 160  
 161    my $tail   = '';
 162    my $suffix = '';
 163    if (@suffices) {
 164      foreach $suffix (@suffices) {
 165        my $pat = ($igncase ? '(?i)' : '') . "($suffix)\$";
 166        if ($basename =~ s/$pat//s) {
 167          $taint .= substr($suffix,0,0);
 168          $tail = $1 . $tail;
 169        }
 170      }
 171    }
 172  
 173    # Ensure taint is propgated from the path to its pieces.
 174    $tail .= $taint;
 175    wantarray ? ($basename .= $taint, $dirpath .= $taint, $tail)
 176              : ($basename .= $taint);
 177  }
 178  
 179  
 180  
 181  =item C<basename>
 182  X<basename> X<filename>
 183  
 184      my $filename = basename($path);
 185      my $filename = basename($path, @suffixes);
 186  
 187  This function is provided for compatibility with the Unix shell command
 188  C<basename(1)>.  It does B<NOT> always return the file name portion of a
 189  path as you might expect.  To be safe, if you want the file name portion of
 190  a path use C<fileparse()>.
 191  
 192  C<basename()> returns the last level of a filepath even if the last
 193  level is clearly directory.  In effect, it is acting like C<pop()> for
 194  paths.  This differs from C<fileparse()>'s behaviour.
 195  
 196      # Both return "bar"
 197      basename("/foo/bar");
 198      basename("/foo/bar/");
 199  
 200  @suffixes work as in C<fileparse()> except all regex metacharacters are
 201  quoted.
 202  
 203      # These two function calls are equivalent.
 204      my $filename = basename("/foo/bar/baz.txt",  ".txt");
 205      my $filename = fileparse("/foo/bar/baz.txt", qr/\Q.txt\E/);
 206  
 207  Also note that in order to be compatible with the shell command,
 208  C<basename()> does not strip off a suffix if it is identical to the
 209  remaining characters in the filename.
 210  
 211  =cut
 212  
 213  
 214  sub basename {
 215    my($path) = shift;
 216  
 217    # From BSD basename(1)
 218    # The basename utility deletes any prefix ending with the last slash `/'
 219    # character present in string (after first stripping trailing slashes)
 220    _strip_trailing_sep($path);
 221  
 222    my($basename, $dirname, $suffix) = fileparse( $path, map("\Q$_\E",@_) );
 223  
 224    # From BSD basename(1)
 225    # The suffix is not stripped if it is identical to the remaining 
 226    # characters in string.
 227    if( length $suffix and !length $basename ) {
 228        $basename = $suffix;
 229    }
 230    
 231    # Ensure that basename '/' == '/'
 232    if( !length $basename ) {
 233        $basename = $dirname;
 234    }
 235  
 236    return $basename;
 237  }
 238  
 239  
 240  
 241  =item C<dirname>
 242  X<dirname>
 243  
 244  This function is provided for compatibility with the Unix shell
 245  command C<dirname(1)> and has inherited some of its quirks.  In spite of
 246  its name it does B<NOT> always return the directory name as you might
 247  expect.  To be safe, if you want the directory name of a path use
 248  C<fileparse()>.
 249  
 250  Only on VMS (where there is no ambiguity between the file and directory
 251  portions of a path) and AmigaOS (possibly due to an implementation quirk in
 252  this module) does C<dirname()> work like C<fileparse($path)>, returning just the
 253  $directories.
 254  
 255      # On VMS and AmigaOS
 256      my $directories = dirname($path);
 257  
 258  When using Unix or MSDOS syntax this emulates the C<dirname(1)> shell function
 259  which is subtly different from how C<fileparse()> works.  It returns all but
 260  the last level of a file path even if the last level is clearly a directory.
 261  In effect, it is not returning the directory portion but simply the path one
 262  level up acting like C<chop()> for file paths.
 263  
 264  Also unlike C<fileparse()>, C<dirname()> does not include a trailing slash on
 265  its returned path.
 266  
 267      # returns /foo/bar.  fileparse() would return /foo/bar/
 268      dirname("/foo/bar/baz");
 269  
 270      # also returns /foo/bar despite the fact that baz is clearly a 
 271      # directory.  fileparse() would return /foo/bar/baz/
 272      dirname("/foo/bar/baz/");
 273  
 274      # returns '.'.  fileparse() would return 'foo/'
 275      dirname("foo/");
 276  
 277  Under VMS, if there is no directory information in the $path, then the
 278  current default device and directory is used.
 279  
 280  =cut
 281  
 282  
 283  sub dirname {
 284      my $path = shift;
 285  
 286      my($type) = $Fileparse_fstype;
 287  
 288      if( $type eq 'VMS' and $path =~ m{/} ) {
 289          # Parse as Unix
 290          local($File::Basename::Fileparse_fstype) = '';
 291          return dirname($path);
 292      }
 293  
 294      my($basename, $dirname) = fileparse($path);
 295  
 296      if ($type eq 'VMS') { 
 297          $dirname ||= $ENV{DEFAULT};
 298      }
 299      elsif ($type eq 'MacOS') {
 300      if( !length($basename) && $dirname !~ /^[^:]+:\z/) {
 301              _strip_trailing_sep($dirname);
 302          ($basename,$dirname) = fileparse $dirname;
 303      }
 304      $dirname .= ":" unless $dirname =~ /:\z/;
 305      }
 306      elsif (grep { $type eq $_ } qw(MSDOS DOS MSWin32 OS2)) { 
 307          _strip_trailing_sep($dirname);
 308          unless( length($basename) ) {
 309          ($basename,$dirname) = fileparse $dirname;
 310          _strip_trailing_sep($dirname);
 311      }
 312      }
 313      elsif ($type eq 'AmigaOS') {
 314          if ( $dirname =~ /:\z/) { return $dirname }
 315          chop $dirname;
 316          $dirname =~ s{[^:/]+\z}{} unless length($basename);
 317      }
 318      else {
 319          _strip_trailing_sep($dirname);
 320          unless( length($basename) ) {
 321          ($basename,$dirname) = fileparse $dirname;
 322          _strip_trailing_sep($dirname);
 323      }
 324      }
 325  
 326      $dirname;
 327  }
 328  
 329  
 330  # Strip the trailing path separator.
 331  sub _strip_trailing_sep  {
 332      my $type = $Fileparse_fstype;
 333  
 334      if ($type eq 'MacOS') {
 335          $_[0] =~ s/([^:]):\z/$1/s;
 336      }
 337      elsif (grep { $type eq $_ } qw(MSDOS DOS MSWin32 OS2)) { 
 338          $_[0] =~ s/([^:])[\\\/]*\z/$1/;
 339      }
 340      else {
 341          $_[0] =~ s{(.)/*\z}{$1}s;
 342      }
 343  }
 344  
 345  
 346  =item C<fileparse_set_fstype>
 347  X<filesystem>
 348  
 349    my $type = fileparse_set_fstype();
 350    my $previous_type = fileparse_set_fstype($type);
 351  
 352  Normally File::Basename will assume a file path type native to your current
 353  operating system (ie. /foo/bar style on Unix, \foo\bar on Windows, etc...).
 354  With this function you can override that assumption.
 355  
 356  Valid $types are "MacOS", "VMS", "AmigaOS", "OS2", "RISCOS",
 357  "MSWin32", "DOS" (also "MSDOS" for backwards bug compatibility),
 358  "Epoc" and "Unix" (all case-insensitive).  If an unrecognized $type is
 359  given "Unix" will be assumed.
 360  
 361  If you've selected VMS syntax, and the file specification you pass to
 362  one of these routines contains a "/", they assume you are using Unix
 363  emulation and apply the Unix syntax rules instead, for that function
 364  call only.
 365  
 366  =back
 367  
 368  =cut
 369  
 370  
 371  BEGIN {
 372  
 373  my @Ignore_Case = qw(MacOS VMS AmigaOS OS2 RISCOS MSWin32 MSDOS DOS Epoc);
 374  my @Types = (@Ignore_Case, qw(Unix));
 375  
 376  sub fileparse_set_fstype {
 377      my $old = $Fileparse_fstype;
 378  
 379      if (@_) {
 380          my $new_type = shift;
 381  
 382          $Fileparse_fstype = 'Unix';  # default
 383          foreach my $type (@Types) {
 384              $Fileparse_fstype = $type if $new_type =~ /^$type/i;
 385          }
 386  
 387          $Fileparse_igncase = 
 388            (grep $Fileparse_fstype eq $_, @Ignore_Case) ? 1 : 0;
 389      }
 390  
 391      return $old;
 392  }
 393  
 394  }
 395  
 396  
 397  1;
 398  
 399  
 400  =head1 SEE ALSO
 401  
 402  L<dirname(1)>, L<basename(1)>, L<File::Spec>