Directory traversal problem

nbernstein has asked for the wisdom of the Perl Monks concerning the following question:

I'm not a great coder. I can usually get things done by using a combination of perl & unix utils, but I'm trying to do a project to help teach myself more. The part I'm working on now is stepping through the filesystem, starting at / listing the directory, and for each item, testing if its a directory or a file, if it's a file it does a stat() and if it's a directory, it lists it and does the same process over again.

The problem is, instead of listing the subdirectories, it combines the parents list with the childs.

For example: listing root gives "bin, boot ... var" instead of listing /bin/ it tries to list /bin/bin, /bin/boot ... /bin/var/

I've been looking at this for hours, and every time i think I make progress I end up going two steps back.

I'm sure the problem will be obvious to someone more versed than I am, and I would appreciate the help. I haven't cleaned this up too much, but if you've got any comments on general coding style, etc. please let me know, I'm here to learn, I don't care if I come off like an idiot.

thanks in advance,
Nick

#! /usr/bin/perl 
use Digest::MD5 qw(md5 md5_hex md5_base64);
use strict;
use diagnostics;
use warnings;

our $debug = 0;

sub dir {
    print "----------------- dir($_[0]) -----------------\n";

    if ( !defined( $_[0] ) ) {
        die("Nothing passed to the dir function\n");
    }
    my $path   = $_[0];
    
    foreach my $file ( lsdir("/") ) {
    #---------------------------------------------------------
    # Step through the results of the lsdir
    # and determine if it is a) a directory
    # or b) a file. For each one, run it's 
    # respective function. 
    #---------------------------------------------------------
    
        print "$file\n" if ( 0 == $debug );
    
        #my $holder = "$path/$file/";
        #print "HOLDER:\t$holder\n" if ( 0 == $debug );
        
        
        my $isdir_result = isdir("$path/$file") if ( 0 == $debug );
        print "ISDIR RESULTS:\t$isdir_result\n" if ( 0 == $debug );
        
        
        if ( 0 == isdir("$path/$file") ) {
            print "Dir:\t/$path/$file/\n";
            if ( '/' eq $path ) {
                # if it's the root directory, just use the file
                print "$file is a directory.\n" if ( 0 == $debug );
                print "instance 1: dir($file)\n";
                dir("/$file");
            } else {
                #otherwise, just use the path
                print "$file is a file.\n" if ( 0 == $debug );
                print "instance 2: dir($file)\n";
                if ( $file !~ m/^\// ){ 
                    $file = "/" . $file;
                }    
                dir($path);
            }
        } elsif ( 1 == isdir("$path/$file") ) {
                print "File:\t/$file\n";
                my %file_info = file("/$file");
                if ( 0 == $debug ) {
                    foreach my $key ( keys %file_info ) {
                    }
                }
            }
        }
    }
    

    sub file {
        print "o0o0o0o0o0o file($_[0]) o0o0o0o0o0o\n";
        my $file = $_[0];
        my %attrib;
        $attrib{name} = $file;

        # stat file
        (
            $attrib{dev},   $attrib{ino},   $attrib{mode},
            $attrib{nlink}, $attrib{uid},   $attrib{gid},
            $attrib{rdev},  $attrib{size},  $attrib{atime},
            $attrib{mtime}, $attrib{ctime}, $attrib{blksize},
            $attrib{blocks}
          )
          = stat($file);

        # compute md5
        open( FILE, $file ) or print "Couldn't open $file!";

        if ( -e $file ) {
            binmode(FILE);

            my $md5 = Digest::MD5->new;
            while (<FILE>) {
                $md5->add($_);
            }
            close(FILE);
            $attrib{md5} = $md5->b64digest;
        } else {
            print "What the hell.... $file doesn't exist?\n";
        }

        # give it back
        return (%attrib);
    }

    sub isdir {
        print "/\/\/\/\/\/\ isdir() /\/\/\/\/\/\ \n";
        print "isdir($_[0])\n";
        my $file = $_[0];
        if ( -d "$file" ) {
            print "ISDIR = YES\n" if ( 0 == $debug );
            return(0);
        } else {
            print "ISDIR = NO\n" if ( 0 == $debug );
            return(1);
        }
    }

    sub lsdir {
        print "************ lsdir($_[0]) **************\n";
        my $dir = $_[0];
        my @files;
        opendir( DIRHANDLE, "$dir" ) || die "Cannot opendir /some/path
+: $!";
        foreach my $file ( sort readdir(DIRHANDLE) ) {
            push( @files, $file ) unless ( $file =~ m/^(\.){1,2}$/ );
            print $file, "\n" if ( 2 == $debug );
        }
        return @files;
    }

    my $path = "/";
    print $path;
    dir("$path");    #|| die( "Couldn't run dir($path)");
[download]

Output:

/----------------- dir(/) -----------------
************ lsdir(/) **************
bin
////// isdir() //////
isdir(//bin)
ISDIR = YES
ISDIR RESULTS:  0
////// isdir() //////
isdir(//bin)
ISDIR = YES
Dir:    ///bin/
bin is a directory.
instance 1: dir(bin)
----------------- dir(/bin) -----------------
************ lsdir(/) **************
bin
////// isdir() //////
isdir(/bin/bin)
ISDIR = NO
ISDIR RESULTS:  1
////// isdir() //////
isdir(/bin/bin)
ISDIR = NO
////// isdir() //////
isdir(/bin/bin)
ISDIR = NO
File:   /bin
o0o0o0o0o0o file(/bin) o0o0o0o0o0o
boot
////// isdir() //////
isdir(/bin/boot)
ISDIR = NO
ISDIR RESULTS:  1
////// isdir() //////
isdir(/bin/boot)
ISDIR = NO
////// isdir() //////
isdir(/bin/boot)
ISDIR = NO
File:   /boot
o0o0o0o0o0o file(/boot) o0o0o0o0o0o
dbmsrv.prt
////// isdir() //////
isdir(/bin/dbmsrv.prt)
ISDIR = NO
ISDIR RESULTS:  1
////// isdir() //////
isdir(/bin/dbmsrv.prt)
ISDIR = NO
////// isdir() //////
isdir(/bin/dbmsrv.prt)
ISDIR = NO
File:   /dbmsrv.prt
o0o0o0o0o0o file(/dbmsrv.prt) o0o0o0o0o0o
dev
////// isdir() //////
isdir(/bin/dev)
ISDIR = NO
ISDIR RESULTS:  1
////// isdir() //////
isdir(/bin/dev)
ISDIR = NO
////// isdir() //////
isdir(/bin/dev)
ISDIR = NO
File:   /dev
o0o0o0o0o0o file(/dev) o0o0o0o0o0o
etc
[download]

2004-11-25 Edited by Arunbear: Changed title from 'My brain hurts', as per Monastery guidelines

Comment on Directory traversal problem Select or Download Code

Replies are listed 'Best First'.
Re: Directory traversal problem by Zaxo (Archbishop) on Nov 25, 2004 at 02:56 UTC
It probably won't ease the pain at first, but File::Find is designed for recursing through directory trees. You can get a hashed stat with File::stat, whose stat returns a reference to a hash like you produce. Also notable when dealing with filenames and directory trees are File::Basename and File::Spec. After Compline, Zaxo	[reply]
Re: Directory traversal problem by Eimi Metamorphoumai (Deacon) on Nov 25, 2004 at 02:01 UTC
Without looking too deeply into it, it looks like the problem is in `dir`, where you have `foreach my $file ( lsdir("/") ) {` [download] So in each directory, it's going ove the contents of the root again. It looks to me like you meant `foreach my $file ( lsdir($path) ) {` [download] Also, stylistically, you've got some very strange things. You seem to be using 0 for true, and 1 for false, and then doing a lot of `if (0 == $debug)` instead of doing a more conventional style of using 1 for true and either 0 or undef for false. That way, your tests could just be `if ($debug)` (same for isdir, and possibly others). And you're calling `isdir` several times, instead of (actually, in addition to) just storing the value returned the first time. It'd be much more natural to do `if (isdir("$path/$file"){ ... } else { ... }` [download]	[reply] [d/l] [select]
Re: Directory traversal problem by zentara (Cardinal) on Nov 25, 2004 at 14:00 UTC
This might help you simplify your life: #!/usr/bin/perl use warnings; use strict; use File::Slurp::Tree; # The tree datastructure is a hash of hashes. The keys of # each hash are names of directories or files. Directories # have hash references as their value, files have a scalar # which holds the contents of the file. my $dir = shift \|\| '.'; my %tree; my $tree = slurp_tree($dir); my $depth = 0; print "$dir\n"; print_keys($tree); sub print_keys { my $href = shift; $depth++; foreach ( keys %$href ) { print ' ' x $depth, "--$_\n"; print_keys( $href->{$_} ) if ref $href->{$_} eq 'HASH'; } $depth--; } [download] I'm not really a human, but I play one on earth. flash japh	[reply] [d/l]