package Archive::Tar::File; use strict; use Carp (); use IO::File; use File::Spec::Unix (); use File::Spec (); use File::Basename (); ### avoid circular use, so only require; require Archive::Tar; use Archive::Tar::Constant; use vars qw[@ISA $VERSION]; #@ISA = qw[Archive::Tar]; $VERSION = '0.02'; ### set value to 1 to oct() it during the unpack ### my $tmpl = [ name => 0, # string mode => 1, # octal uid => 1, # octal gid => 1, # octal size => 1, # octal mtime => 1, # octal chksum => 1, # octal type => 0, # character linkname => 0, # string magic => 0, # string version => 0, # 2 bytes uname => 0, # string gname => 0, # string devmajor => 1, # octal devminor => 1, # octal prefix => 0, ### end UNPACK items ### raw => 0, # the raw data chunk data => 0, # the data associated with the file -- # This might be very memory intensive ]; ### install get/set accessors for this object. for ( my $i=0; $i[$i]; no strict 'refs'; *{__PACKAGE__."::$key"} = sub { my $self = shift; $self->{$key} = $_[0] if @_; ### just in case the key is not there or undef or something ### { local $^W = 0; return $self->{$key}; } } } =head1 NAME Archive::Tar::File - a subclass for in-memory extracted file from Archive::Tar =head1 SYNOPSIS my @items = $tar->get_files; print $_->name, ' ', $_->size, "\n" for @items; print $object->get_content; $object->replace_content('new content'); $object->rename( 'new/full/path/to/file.c' ); =head1 DESCRIPTION Archive::Tar::Files provides a neat little object layer for in-memory extracted files. It's mostly used internally in Archive::Tar to tidy up the code, but there's no reason users shouldn't use this API as well. =head2 Accessors A lot of the methods in this package are accessors to the various fields in the tar header: =over 4 =item name The file's name =item mode The file's mode =item uid The user id owning the file =item gid The group id owning the file =item size File size in bytes =item mtime Modification time. Adjusted to mac-time on MacOS if required =item chksum Checksum field for the tar header =item type File type -- numeric, but comparable to exported constants -- see Archive::Tar's documentation =item linkname If the file is a symlink, the file it's pointing to =item magic Tar magic string -- not useful for most users =item version Tar version string -- not useful for most users =item uname The user name that owns the file =item gname The group name that owns the file =item devmajor Device major number in case of a special file =item devminor Device minor number in case of a special file =item prefix Any directory to prefix to the extraction path, if any =item raw Raw tar header -- not useful for most users =back =head1 Methods =head2 Archive::Tar::File->new( file => $path ) Returns a new Archive::Tar::File object from an existing file. Returns undef on failure. =head2 Archive::Tar::File->new( data => $path, $data, $opt ) Returns a new Archive::Tar::File object from data. C<$path> defines the file name (which need not exist), C<$data> the file contents, and C<$opt> is a reference to a hash of attributes which may be used to override the default attributes (fields in the tar header), which are described above in the Accessors section. Returns undef on failure. =head2 Archive::Tar::File->new( chunk => $chunk ) Returns a new Archive::Tar::File object from a raw 512-byte tar archive chunk. Returns undef on failure. =cut sub new { my $class = shift; my $what = shift; my $obj = ($what eq 'chunk') ? __PACKAGE__->_new_from_chunk( @_ ) : ($what eq 'file' ) ? __PACKAGE__->_new_from_file( @_ ) : ($what eq 'data' ) ? __PACKAGE__->_new_from_data( @_ ) : undef; return $obj; } ### copies the data, creates a clone ### sub clone { my $self = shift; return bless { %$self }, ref $self; } sub _new_from_chunk { my $class = shift; my $chunk = shift or return; # 512 bytes of tar header my %hash = @_; ### filter any arguments on defined-ness of values. ### this allows overriding from what the tar-header is saying ### about this tar-entry. Particularly useful for @LongLink files my %args = map { $_ => $hash{$_} } grep { defined $hash{$_} } keys %hash; ### makes it start at 0 actually... :) ### my $i = -1; my %entry = map { $tmpl->[++$i] => $tmpl->[++$i] ? oct $_ : $_ } map { /^([^\0]*)/ } unpack( UNPACK, $chunk ); my $obj = bless { %entry, %args }, $class; ### magic is a filetype string.. it should have something like 'ustar' or ### something similar... if the chunk is garbage, skip it return unless $obj->magic !~ /\W/; ### store the original chunk ### $obj->raw( $chunk ); $obj->type(FILE) if ( (!length $obj->type) or ($obj->type =~ /\W/) ); $obj->type(DIR) if ( ($obj->is_file) && ($obj->name =~ m|/$|) ); return $obj; } sub _new_from_file { my $class = shift; my $path = shift; ### path has to at least exist return unless defined $path; my $type = __PACKAGE__->_filetype($path); my $data = ''; READ: { unless ($type == DIR ) { my $fh = IO::File->new; unless( $fh->open($path) ) { ### dangling symlinks are fine, stop reading but continue ### creating the object last READ if $type == SYMLINK; ### otherwise, return from this function -- ### anything that's *not* a symlink should be ### resolvable return; } ### binmode needed to read files properly on win32 ### binmode $fh; $data = do { local $/; <$fh> }; close $fh; } } my @items = qw[mode uid gid size mtime]; my %hash = map { shift(@items), $_ } (lstat $path)[2,4,5,7,9]; if (ON_VMS) { ### VMS has two UID modes, traditional and POSIX. Normally POSIX is ### not used. We currently do not have an easy way to see if we are in ### POSIX mode. In traditional mode, the UID is actually the VMS UIC. ### The VMS UIC has the upper 16 bits is the GID, which in many cases ### the VMS UIC will be larger than 209715, the largest that TAR can ### handle. So for now, assume it is traditional if the UID is larger ### than 0x10000. if ($hash{uid} > 0x10000) { $hash{uid} = $hash{uid} & 0xFFFF; } ### The file length from stat() is the physical length of the file ### However the amount of data read in may be more for some file types. ### Fixed length files are read past the logical EOF to end of the block ### containing. Other file types get expanded on read because record ### delimiters are added. my $data_len = length $data; $hash{size} = $data_len if $hash{size} < $data_len; } ### you *must* set size == 0 on symlinks, or the next entry will be ### though of as the contents of the symlink, which is wrong. ### this fixes bug #7937 $hash{size} = 0 if ($type == DIR or $type == SYMLINK); $hash{mtime} -= TIME_OFFSET; ### strip the high bits off the mode, which we don't need to store $hash{mode} = STRIP_MODE->( $hash{mode} ); ### probably requires some file path munging here ... ### ### name and prefix are set later my $obj = { %hash, name => '', chksum => CHECK_SUM, type => $type, linkname => ($type == SYMLINK and CAN_READLINK) ? readlink $path : '', magic => MAGIC, version => TAR_VERSION, uname => UNAME->( $hash{uid} ), gname => GNAME->( $hash{gid} ), devmajor => 0, # not handled devminor => 0, # not handled prefix => '', data => $data, }; bless $obj, $class; ### fix up the prefix and file from the path my($prefix,$file) = $obj->_prefix_and_file( $path ); $obj->prefix( $prefix ); $obj->name( $file ); return $obj; } sub _new_from_data { my $class = shift; my $path = shift; return unless defined $path; my $data = shift; return unless defined $data; my $opt = shift; my $obj = { data => $data, name => '', mode => MODE, uid => UID, gid => GID, size => length $data, mtime => time - TIME_OFFSET, chksum => CHECK_SUM, type => FILE, linkname => '', magic => MAGIC, version => TAR_VERSION, uname => UNAME->( UID ), gname => GNAME->( GID ), devminor => 0, devmajor => 0, prefix => '', }; ### overwrite with user options, if provided ### if( $opt and ref $opt eq 'HASH' ) { for my $key ( keys %$opt ) { ### don't write bogus options ### next unless exists $obj->{$key}; $obj->{$key} = $opt->{$key}; } } bless $obj, $class; ### fix up the prefix and file from the path my($prefix,$file) = $obj->_prefix_and_file( $path ); $obj->prefix( $prefix ); $obj->name( $file ); return $obj; } sub _prefix_and_file { my $self = shift; my $path = shift; my ($vol, $dirs, $file) = File::Spec->splitpath( $path, $self->is_dir ); my @dirs = File::Spec->splitdir( $dirs ); ### so sometimes the last element is '' -- probably when trailing ### dir slashes are encountered... this is is of course pointless, ### so remove it pop @dirs while @dirs and not length $dirs[-1]; ### if it's a directory, then $file might be empty $file = pop @dirs if $self->is_dir and not length $file; ### splitting ../ gives you the relative path in native syntax map { $_ = '..' if $_ eq '-' } @dirs if ON_VMS; my $prefix = File::Spec::Unix->catdir( grep { length } $vol, @dirs ); return( $prefix, $file ); } sub _filetype { my $self = shift; my $file = shift; return unless defined $file; return SYMLINK if (-l $file); # Symlink return FILE if (-f _); # Plain file return DIR if (-d _); # Directory return FIFO if (-p _); # Named pipe return SOCKET if (-S _); # Socket return BLOCKDEV if (-b _); # Block special return CHARDEV if (-c _); # Character special ### shouldn't happen, this is when making archives, not reading ### return LONGLINK if ( $file eq LONGLINK_NAME ); return UNKNOWN; # Something else (like what?) } ### this method 'downgrades' a file to plain file -- this is used for ### symlinks when FOLLOW_SYMLINKS is true. sub _downgrade_to_plainfile { my $entry = shift; $entry->type( FILE ); $entry->mode( MODE ); $entry->linkname(''); return 1; } =head2 $bool = $file->extract( [ $alternative_name ] ) Extract this object, optionally to an alternative name. See C<< Archive::Tar->extract_file >> for details. Returns true on success and false on failure. =cut sub extract { my $self = shift; local $Carp::CarpLevel += 1; return Archive::Tar->_extract_file( $self, @_ ); } =head2 $path = $file->full_path Returns the full path from the tar header; this is basically a concatenation of the C and C fields. =cut sub full_path { my $self = shift; ### if prefix field is emtpy return $self->name unless defined $self->prefix and length $self->prefix; ### or otherwise, catfile'd return File::Spec::Unix->catfile( $self->prefix, $self->name ); } =head2 $bool = $file->validate Done by Archive::Tar internally when reading the tar file: validate the header against the checksum to ensure integer tar file. Returns true on success, false on failure =cut sub validate { my $self = shift; my $raw = $self->raw; ### don't know why this one is different from the one we /write/ ### substr ($raw, 148, 8) = " "; ### bug #43513: [PATCH] Accept wrong checksums from SunOS and HP-UX tar ### like GNU tar does. See here for details: ### http://www.gnu.org/software/tar/manual/tar.html#SEC139 ### so we do both a signed AND unsigned validate. if one succeeds, that's ### good enough return ( (unpack ("%16C*", $raw) == $self->chksum) or (unpack ("%16c*", $raw) == $self->chksum)) ? 1 : 0; } =head2 $bool = $file->has_content Returns a boolean to indicate whether the current object has content. Some special files like directories and so on never will have any content. This method is mainly to make sure you don't get warnings for using uninitialized values when looking at an object's content. =cut sub has_content { my $self = shift; return defined $self->data() && length $self->data() ? 1 : 0; } =head2 $content = $file->get_content Returns the current content for the in-memory file =cut sub get_content { my $self = shift; $self->data( ); } =head2 $cref = $file->get_content_by_ref Returns the current content for the in-memory file as a scalar reference. Normal users won't need this, but it will save memory if you are dealing with very large data files in your tar archive, since it will pass the contents by reference, rather than make a copy of it first. =cut sub get_content_by_ref { my $self = shift; return \$self->{data}; } =head2 $bool = $file->replace_content( $content ) Replace the current content of the file with the new content. This only affects the in-memory archive, not the on-disk version until you write it. Returns true on success, false on failure. =cut sub replace_content { my $self = shift; my $data = shift || ''; $self->data( $data ); $self->size( length $data ); return 1; } =head2 $bool = $file->rename( $new_name ) Rename the current file to $new_name. Note that you must specify a Unix path for $new_name, since per tar standard, all files in the archive must be Unix paths. Returns true on success and false on failure. =cut sub rename { my $self = shift; my $path = shift; return unless defined $path; my ($prefix,$file) = $self->_prefix_and_file( $path ); $self->name( $file ); $self->prefix( $prefix ); return 1; } =head1 Convenience methods To quickly check the type of a C object, you can use the following methods: =over 4 =item $file->is_file Returns true if the file is of type C =item $file->is_dir Returns true if the file is of type C =item $file->is_hardlink Returns true if the file is of type C =item $file->is_symlink Returns true if the file is of type C =item $file->is_chardev Returns true if the file is of type C =item $file->is_blockdev Returns true if the file is of type C =item $file->is_fifo Returns true if the file is of type C =item $file->is_socket Returns true if the file is of type C =item $file->is_longlink Returns true if the file is of type C. Should not happen after a successful C. =item $file->is_label Returns true if the file is of type C