package File::Find; use 5.005_64; require Exporter; require Cwd; =head1 NAME find - traverse a file tree finddepth - traverse a directory structure depth-first =head1 SYNOPSIS use File::Find; find(\&wanted, '/foo', '/bar'); sub wanted { ... } use File::Find; finddepth(\&wanted, '/foo', '/bar'); sub wanted { ... } use File::Find; find({ wanted => \&process, follow => 1 }, '.'); =head1 DESCRIPTION The first argument to find() is either a hash reference describing the operations to be performed for each file, or a code reference. Here are the possible keys for the hash: =over 3 =item C The value should be a code reference. This code reference is called I below. =item C Reports the name of a directory only AFTER all its entries have been reported. Entry point finddepth() is a shortcut for specifying C<{ bydepth => 1 }> in the first argument of find(). =item C The value should be a code reference. This code reference is used to preprocess a directory; it is called after readdir() but before the loop that calls the wanted() function. It is called with a list of strings and is expected to return a list of strings. The code can be used to sort the strings alphabetically, numerically, or to filter out directory entries based on their name alone. =item C The value should be a code reference. It is invoked just before leaving the current directory. It is called in void context with no arguments. The name of the current directory is in $File::Find::dir. This hook is handy for summarizing a directory, such as calculating its disk usage. =item C Causes symbolic links to be followed. Since directory trees with symbolic links (followed) may contain files more than once and may even have cycles, a hash has to be built up with an entry for each file. This might be expensive both in space and time for a large directory tree. See I and I below. If either I or I is in effect: =over 6 =item * It is guaranteed that an I has been called before the user's I function is called. This enables fast file checks involving S< _>. =item * There is a variable C<$File::Find::fullname> which holds the absolute pathname of the file with all symbolic links resolved =back =item C This is similar to I except that it may report some files more than once. It does detect cycles, however. Since only symbolic links have to be hashed, this is much cheaper both in space and time. If processing a file more than once (by the user's I function) is worse than just taking time, the option I should be used. =item C C, which is the default, causes all files which are neither directories nor symbolic links to be ignored if they are about to be processed a second time. If a directory or a symbolic link are about to be processed a second time, File::Find dies. C causes File::Find to die if any file is about to be processed a second time. C causes File::Find to ignore any duplicate files and dirctories but to proceed normally otherwise. =item C Does not C to each directory as it recurses. The wanted() function will need to be aware of this, of course. In this case, C<$_> will be the same as C<$File::Find::name>. =item C If find is used in taint-mode (-T command line switch or if EUID != UID or if EGID != GID) then internally directory names have to be untainted before they can be cd'ed to. Therefore they are checked against a regular expression I. Note that all names passed to the user's I function are still tainted. =item C See above. This should be set using the C quoting operator. The default is set to C. Note that the parantheses are vital. =item C If set, directories (subtrees) which fail the I are skipped. The default is to 'die' in such a case. =back The wanted() function does whatever verifications you want. C<$File::Find::dir> contains the current directory name, and C<$_> the current filename within that directory. C<$File::Find::name> contains the complete pathname to the file. You are chdir()'d to C<$File::Find::dir> when the function is called, unless C was specified. When or are in effect, there is also a C<$File::Find::fullname>. The function may set C<$File::Find::prune> to prune the tree unless C was specified. Unless C or C is specified, for compatibility reasons (find.pl, find2perl) there are in addition the following globals available: C<$File::Find::topdir>, C<$File::Find::topdev>, C<$File::Find::topino>, C<$File::Find::topmode> and C<$File::Find::topnlink>. This library is useful for the C tool, which when fed, find2perl / -name .nfs\* -mtime +7 \ -exec rm -f {} \; -o -fstype nfs -prune produces something like: sub wanted { /^\.nfs.*\z/s && (($dev, $ino, $mode, $nlink, $uid, $gid) = lstat($_)) && int(-M _) > 7 && unlink($_) || ($nlink || (($dev, $ino, $mode, $nlink, $uid, $gid) = lstat($_))) && $dev < 0 && ($File::Find::prune = 1); } Set the variable C<$File::Find::dont_use_nlink> if you're using AFS, since AFS cheats. Here's another interesting wanted function. It will find all symlinks that don't resolve: sub wanted { -l && !-e && print "bogus link: $File::Find::name\n"; } See also the script C on CPAN for a nice application of this module. =head1 CAVEAT Be aware that the option to follow symbolic links can be dangerous. Depending on the structure of the directory tree (including symbolic links to directories) you might traverse a given (physical) directory more than once (only if C is in effect). Furthermore, deleting or changing files in a symbolically linked directory might cause very unpleasant surprises, since you delete or change files in an unknown directory. =cut @ISA = qw(Exporter); @EXPORT = qw(find finddepth); use strict; my $Is_VMS; require File::Basename; my %SLnkSeen; my ($wanted_callback, $avoid_nlink, $bydepth, $no_chdir, $follow, $follow_skip, $full_check, $untaint, $untaint_skip, $untaint_pat, $pre_process, $post_process); sub contract_name { my ($cdir,$fn) = @_; return substr($cdir,0,rindex($cdir,'/')) if $fn eq '.'; $cdir = substr($cdir,0,rindex($cdir,'/')+1); $fn =~ s|^\./||; my $abs_name= $cdir . $fn; if (substr($fn,0,3) eq '../') { do 1 while ($abs_name=~ s|/(?>[^/]+)/\.\./|/|); } return $abs_name; } sub PathCombine($$) { my ($Base,$Name) = @_; my $AbsName; if (substr($Name,0,1) eq '/') { $AbsName= $Name; } else { $AbsName= contract_name($Base,$Name); } # (simple) check for recursion my $newlen= length($AbsName); if ($newlen <= length($Base)) { if (($newlen == length($Base) || substr($Base,$newlen,1) eq '/') && $AbsName eq substr($Base,0,$newlen)) { return undef; } } return $AbsName; } sub Follow_SymLink($) { my ($AbsName) = @_; my ($NewName,$DEV, $INO); ($DEV, $INO)= lstat $AbsName; while (-l _) { if ($SLnkSeen{$DEV, $INO}++) { if ($follow_skip < 2) { die "$AbsName is encountered a second time"; } else { return undef; } } $NewName= PathCombine($AbsName, readlink($AbsName)); unless(defined $NewName) { if ($follow_skip < 2) { die "$AbsName is a recursive symbolic link"; } else { return undef; } } else { $AbsName= $NewName; } ($DEV, $INO) = lstat($AbsName); return undef unless defined $DEV; # dangling symbolic link } if ($full_check && $SLnkSeen{$DEV, $INO}++) { if ($follow_skip < 1) { die "$AbsName encountered a second time"; } else { return undef; } } return $AbsName; } our($dir, $name, $fullname, $prune); sub _find_dir_symlnk($$$); sub _find_dir($$$); sub _find_opt { my $wanted = shift; die "invalid top directory" unless defined $_[0]; my $cwd = $wanted->{bydepth} ? Cwd::fastcwd() : Cwd::cwd(); my $cwd_untainted = $cwd; $wanted_callback = $wanted->{wanted}; $bydepth = $wanted->{bydepth}; $pre_process = $wanted->{preprocess}; $post_process = $wanted->{postprocess}; $no_chdir = $wanted->{no_chdir}; $full_check = $wanted->{follow}; $follow = $full_check || $wanted->{follow_fast}; $follow_skip = $wanted->{follow_skip}; $untaint = $wanted->{untaint}; $untaint_pat = $wanted->{untaint_pattern}; $untaint_skip = $wanted->{untaint_skip}; # for compatability reasons (find.pl, find2perl) our ($topdir, $topdev, $topino, $topmode, $topnlink); # a symbolic link to a directory doesn't increase the link count $avoid_nlink = $follow || $File::Find::dont_use_nlink; if ( $untaint ) { $cwd_untainted= $1 if $cwd_untainted =~ m|$untaint_pat|; die "insecure cwd in find(depth)" unless defined($cwd_untainted); } my ($abs_dir, $Is_Dir); Proc_Top_Item: foreach my $TOP (@_) { my $top_item = $TOP; $top_item =~ s|/\z|| unless $top_item eq '/'; $Is_Dir= 0; ($topdev,$topino,$topmode,$topnlink) = stat $top_item; if ($follow) { if (substr($top_item,0,1) eq '/') { $abs_dir = $top_item; } elsif ($top_item eq '.') { $abs_dir = $cwd; } else { # care about any ../ $abs_dir = contract_name("$cwd/",$top_item); } $abs_dir= Follow_SymLink($abs_dir); unless (defined $abs_dir) { warn "$top_item is a dangling symbolic link\n"; next Proc_Top_Item; } if (-d _) { _find_dir_symlnk($wanted, $abs_dir, $top_item); $Is_Dir= 1; } } else { # no follow $topdir = $top_item; unless (defined $topnlink) { warn "Can't stat $top_item: $!\n"; next Proc_Top_Item; } if (-d _) { $top_item =~ s/\.dir\z// if $Is_VMS; _find_dir($wanted, $top_item, $topnlink); $Is_Dir= 1; } else { $abs_dir= $top_item; } } unless ($Is_Dir) { unless (($_,$dir) = File::Basename::fileparse($abs_dir)) { ($dir,$_) = ('./', $top_item); } $abs_dir = $dir; if ($untaint) { my $abs_dir_save = $abs_dir; $abs_dir = $1 if $abs_dir =~ m|$untaint_pat|; unless (defined $abs_dir) { if ($untaint_skip == 0) { die "directory $abs_dir_save is still tainted"; } else { next Proc_Top_Item; } } } unless ($no_chdir or chdir $abs_dir) { warn "Couldn't chdir $abs_dir: $!\n"; next Proc_Top_Item; } $name = $abs_dir . $_; { &$wanted_callback }; # protect against wild "next" } $no_chdir or chdir $cwd_untainted; } } # API: # $wanted # $p_dir : "parent directory" # $nlink : what came back from the stat # preconditions: # chdir (if not no_chdir) to dir sub _find_dir($$$) { my ($wanted, $p_dir, $nlink) = @_; my ($CdLvl,$Level) = (0,0); my @Stack; my @filenames; my ($subcount,$sub_nlink); my $SE= []; my $dir_name= $p_dir; my $dir_pref= ( $p_dir eq '/' ? '/' : "$p_dir/" ); my $dir_rel= '.'; # directory name relative to current directory local ($dir, $name, $prune, *DIR); unless ($no_chdir or $p_dir eq '.') { my $udir = $p_dir; if ($untaint) { $udir = $1 if $p_dir =~ m|$untaint_pat|; unless (defined $udir) { if ($untaint_skip == 0) { die "directory $p_dir is still tainted"; } else { return; } } } unless (chdir $udir) { warn "Can't cd to $udir: $!\n"; return; } } push @Stack,[$CdLvl,$p_dir,$dir_rel,-1] if $bydepth; while (defined $SE) { unless ($bydepth) { $dir= $p_dir; $name= $dir_name; $_= ($no_chdir ? $dir_name : $dir_rel ); # prune may happen here $prune= 0; { &$wanted_callback }; # protect against wild "next" next if $prune; } # change to that directory unless ($no_chdir or $dir_rel eq '.') { my $udir= $dir_rel; if ($untaint) { $udir = $1 if $dir_rel =~ m|$untaint_pat|; unless (defined $udir) { if ($untaint_skip == 0) { die "directory (" . ($p_dir ne '/' ? $p_dir : '') . "/) $dir_rel is still tainted"; } } } unless (chdir $udir) { warn "Can't cd to (" . ($p_dir ne '/' ? $p_dir : '') . "/) $udir : $!\n"; next; } $CdLvl++; } $dir= $dir_name; # Get the list of files in the current directory. unless (opendir DIR, ($no_chdir ? $dir_name : '.')) { warn "Can't opendir($dir_name): $!\n"; next; } @filenames = readdir DIR; closedir(DIR); @filenames = &$pre_process(@filenames) if $pre_process; push @Stack,[$CdLvl,$dir_name,"",-2] if $post_process; if ($nlink == 2 && !$avoid_nlink) { # This dir has no subdirectories. for my $FN (@filenames) { next if $FN =~ /^\.{1,2}\z/; $name = $dir_pref . $FN; $_ = ($no_chdir ? $name : $FN); { &$wanted_callback }; # protect against wild "next" } } else { # This dir has subdirectories. $subcount = $nlink - 2; for my $FN (@filenames) { next if $FN =~ /^\.{1,2}\z/; if ($subcount > 0 || $avoid_nlink) { # Seen all the subdirs? # check for directoriness. # stat is faster for a file in the current directory $sub_nlink = (lstat ($no_chdir ? $dir_pref . $FN : $FN))[3]; if (-d _) { --$subcount; $FN =~ s/\.dir\z// if $Is_VMS; push @Stack,[$CdLvl,$dir_name,$FN,$sub_nlink]; } else { $name = $dir_pref . $FN; $_= ($no_chdir ? $name : $FN); { &$wanted_callback }; # protect against wild "next" } } else { $name = $dir_pref . $FN; $_= ($no_chdir ? $name : $FN); { &$wanted_callback }; # protect against wild "next" } } } } continue { while ( defined ($SE = pop @Stack) ) { ($Level, $p_dir, $dir_rel, $nlink) = @$SE; if ($CdLvl > $Level && !$no_chdir) { my $tmp = join('/',('..') x ($CdLvl-$Level)); die "Can't cd to $dir_name" . $tmp unless chdir ($tmp); $CdLvl = $Level; } $dir_name = ($p_dir eq '/' ? "/$dir_rel" : "$p_dir/$dir_rel"); $dir_pref = "$dir_name/"; if ( $nlink == -2 ) { $name = $dir = $p_dir; $_ = "."; &$post_process; # End-of-directory processing } elsif ( $nlink < 0 ) { # must be finddepth, report dirname now $name = $dir_name; if ( substr($name,-2) eq '/.' ) { $name =~ s|/\.$||; } $dir = $p_dir; $_ = ($no_chdir ? $dir_name : $dir_rel ); if ( substr($_,-2) eq '/.' ) { s|/\.$||; } { &$wanted_callback }; # protect against wild "next" } else { push @Stack,[$CdLvl,$p_dir,$dir_rel,-1] if $bydepth; last; } } } } # API: # $wanted # $dir_loc : absolute location of a dir # $p_dir : "parent directory" # preconditions: # chdir (if not no_chdir) to dir sub _find_dir_symlnk($$$) { my ($wanted, $dir_loc, $p_dir) = @_; my @Stack; my @filenames; my $new_loc; my $pdir_loc = $dir_loc; my $SE = []; my $dir_name = $p_dir; my $dir_pref = ( $p_dir eq '/' ? '/' : "$p_dir/" ); my $loc_pref = ( $dir_loc eq '/' ? '/' : "$dir_loc/" ); my $dir_rel = '.'; # directory name relative to current directory my $byd_flag; # flag for pending stack entry if $bydepth local ($dir, $name, $fullname, $prune, *DIR); unless ($no_chdir or $p_dir eq '.') { my $udir = $dir_loc; if ($untaint) { $udir = $1 if $dir_loc =~ m|$untaint_pat|; unless (defined $udir) { if ($untaint_skip == 0) { die "directory $dir_loc is still tainted"; } else { return; } } } unless (chdir $udir) { warn "Can't cd to $udir: $!\n"; return; } } push @Stack,[$dir_loc,$pdir_loc,$p_dir,$dir_rel,-1] if $bydepth; while (defined $SE) { unless ($bydepth) { # change to parent directory unless ($no_chdir) { my $udir = $pdir_loc; if ($untaint) { $udir = $1 if $pdir_loc =~ m|$untaint_pat|; } unless (chdir $udir) { warn "Can't cd to $udir: $!\n"; next; } } $dir= $p_dir; $name= $dir_name; $_= ($no_chdir ? $dir_name : $dir_rel ); $fullname= $dir_loc; # prune may happen here $prune= 0; lstat($_); # make sure file tests with '_' work { &$wanted_callback }; # protect against wild "next" next if $prune; } # change to that directory unless ($no_chdir or $dir_rel eq '.') { my $udir = $dir_loc; if ($untaint) { $udir = $1 if $dir_loc =~ m|$untaint_pat|; unless (defined $udir ) { if ($untaint_skip == 0) { die "directory $dir_loc is still tainted"; } else { next; } } } unless (chdir $udir) { warn "Can't cd to $udir: $!\n"; next; } } $dir = $dir_name; # Get the list of files in the current directory. unless (opendir DIR, ($no_chdir ? $dir_loc : '.')) { warn "Can't opendir($dir_loc): $!\n"; next; } @filenames = readdir DIR; closedir(DIR); for my $FN (@filenames) { next if $FN =~ /^\.{1,2}\z/; # follow symbolic links / do an lstat $new_loc = Follow_SymLink($loc_pref.$FN); # ignore if invalid symlink next unless defined $new_loc; if (-d _) { push @Stack,[$new_loc,$dir_loc,$dir_name,$FN,1]; } else { $fullname = $new_loc; $name = $dir_pref . $FN; $_ = ($no_chdir ? $name : $FN); { &$wanted_callback }; # protect against wild "next" } } } continue { while (defined($SE = pop @Stack)) { ($dir_loc, $pdir_loc, $p_dir, $dir_rel, $byd_flag) = @$SE; $dir_name = ($p_dir eq '/' ? "/$dir_rel" : "$p_dir/$dir_rel"); $dir_pref = "$dir_name/"; $loc_pref = "$dir_loc/"; if ( $byd_flag < 0 ) { # must be finddepth, report dirname now unless ($no_chdir or $dir_rel eq '.') { my $udir = $pdir_loc; if ($untaint) { $udir = $1 if $dir_loc =~ m|$untaint_pat|; } unless (chdir $udir) { warn "Can't cd to $udir: $!\n"; next; } } $fullname = $dir_loc; $name = $dir_name; if ( substr($name,-2) eq '/.' ) { $name =~ s|/\.$||; } $dir = $p_dir; $_ = ($no_chdir ? $dir_name : $dir_rel); if ( substr($_,-2) eq '/.' ) { s|/\.$||; } lstat($_); # make sure file tests with '_' work { &$wanted_callback }; # protect against wild "next" } else { push @Stack,[$dir_loc, $pdir_loc, $p_dir, $dir_rel,-1] if $bydepth; last; } } } } sub wrap_wanted { my $wanted = shift; if ( ref($wanted) eq 'HASH' ) { if ( $wanted->{follow} || $wanted->{follow_fast}) { $wanted->{follow_skip} = 1 unless defined $wanted->{follow_skip}; } if ( $wanted->{untaint} ) { $wanted->{untaint_pattern} = qr|^([-+@\w./]+)$| unless defined $wanted->{untaint_pattern}; $wanted->{untaint_skip} = 0 unless defined $wanted->{untaint_skip}; } return $wanted; } else { return { wanted => $wanted }; } } sub find { my $wanted = shift; _find_opt(wrap_wanted($wanted), @_); %SLnkSeen= (); # free memory } sub finddepth { my $wanted = wrap_wanted(shift); $wanted->{bydepth} = 1; _find_opt($wanted, @_); %SLnkSeen= (); # free memory } # These are hard-coded for now, but may move to hint files. if ($^O eq 'VMS') { $Is_VMS = 1; $File::Find::dont_use_nlink = 1; } $File::Find::dont_use_nlink = 1 if $^O eq 'os2' || $^O eq 'dos' || $^O eq 'amigaos' || $^O eq 'MSWin32' || $^O eq 'cygwin' || $^O eq 'epoc'; # Set dont_use_nlink in your hint file if your system's stat doesn't # report the number of links in a directory as an indication # of the number of files. # See, e.g. hints/machten.sh for MachTen 2.2. unless ($File::Find::dont_use_nlink) { require Config; $File::Find::dont_use_nlink = 1 if ($Config::Config{'dont_use_nlink'}); } 1;