How do you validate filenames?

I got bit in the butt.

So here is my sob story. I have some old perl code that moves mp3 files and renames them based on the mp3 tag info. Well, I noticed the other day that a few songs had silenty disapeared during the move.

The culprit was failure to validate the filenames. If an invalid character was in the destination filename, the file was moved into oblivion with no error. oooopps...

So I did a quick search for some module that would validate filenames and could find nothing but this module VMS::FileUtils::SafeName that does not quite apply :) ...

So of course I wrote some quick code to do the job.. But was wondering how everyone else is handling this situation. I was suprised to not find a relevant module on CPAN but maybee I am just search impaired this evening.

Would also appreciate code review, since I suck with regexes! :) 

use strict;
use warnings;
my $INV_CHAR;

print "Testing for valid win32 filenames...\nThe following characters 
+are invalid.\n";
print '\\/:*?"<>|',"\n\n";

while (<DATA>) {
  chomp;
  print "filename: [",$_,"] is";
  print validate_it($_) ? " valid.\n" :
                             " not valid!\n\t Filename contains \"$INV
+_CHAR\"\n" .
                            "\ttry: [" . sanitize_it($_,'_') . "]\n";
}

sub validate_it {
  local $_;
  $_ = shift;

  return /\\|\/|:|\*|\?|"|<|>|\|/ ? do { $INV_CHAR = $&; undef; } :
                  1;
}

sub sanitize_it {
  $_[0] =~ s/\\|\/|:|\*|\?|"|<|>|\|/$_[1]/g;
  return $_[0];
}


__DATA__
file1
file2$is
this)ok
this-ok_too..
this-good.mp4
bad:
b:a:d?--\
not<good>
*is*bad/
?what?is:good
this|ok|not

[download]
UPDATE

To clear up any confusion about the purpose of this post. I'm not looking for solutions to the file copy/moving. I am looking for some discusion on handling filename validation/sanitizing.

My Questions are: (1) Do fellow perlmonks routinely validate filenames? If so, how do you do it? (2) Any inherit problems with how my routines deal with validating/sanitizing windows filenames??

zzSPECTREz

In reply to Validate windows filenames. by zzspectrez

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