package Archive::Tar::File;
use strict;
use IO::File;
use File::Spec::Unix ();
use File::Spec ();
use File::Basename ();
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; $i<scalar @$tmpl ; $i+=2 ) {
my $key = $tmpl->[$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 new( file => $path )
Returns a new Archive::Tar::File object from an existing file.
Returns undef on failure.
=head2 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 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;
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 or return;
my $type = __PACKAGE__->_filetype($path);
my $data = '';
unless ($type == DIR) {
my $fh = IO::File->new;
$fh->open($path) or 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];
### 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 or return;
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;
my $prefix = File::Spec::Unix->catdir(
grep { length } $vol, @dirs
);
return( $prefix, $file );
}
sub _filetype {
my $self = shift;
my $file = shift or return;
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 full_path
Returns the full path from the tar header; this is basically a
concatenation of the C<prefix> and C<name> 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 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) = " ";
return unpack ("%16C*", $raw) == $self->chksum ? 1 : 0;
}
=head2 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 get_content
Returns the current content for the in-memory file
=cut
sub get_content {
my $self = shift;
$self->data( );
}
=head2 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 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 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 $path = shift or return;
my ($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<Archive::Tar::File> object, you can
use the following methods:
=over 4
=item is_file
Returns true if the file is of type C<file>
=item is_dir
Returns true if the file is of type C<dir>
=item is_hardlink
Returns true if the file is of type C<hardlink>
=item is_symlink
Returns true if the file is of type C<symlink>
=item is_chardev
Returns true if the file is of type C<chardev>
=item is_blockdev
Returns true if the file is of type C<blockdev>
=item is_fifo
Returns true if the file is of type C<fifo>
=item is_socket
Returns true if the file is of type C<socket>
=item is_longlink
Returns true if the file is of type C<LongLink>.
Should not happen after a successful C<read>.
=item is_label
Returns true if the file is of type C<Label>.
Should not happen after a successful C<read>.
=item is_unknown
Returns true if the file type is C<unknown>
=back
=cut
#stupid perl5.5.3 needs to warn if it's not numeric
sub is_file { local $^W; FILE == $_[0]->type }
sub is_dir { local $^W; DIR == $_[0]->type }
sub is_hardlink { local $^W; HARDLINK == $_[0]->type }
sub is_symlink { local $^W; SYMLINK == $_[0]->type }
sub is_chardev { local $^W; CHARDEV == $_[0]->type }
sub is_blockdev { local $^W; BLOCKDEV == $_[0]->type }
sub is_fifo { local $^W; FIFO == $_[0]->type }
sub is_socket { local $^W; SOCKET == $_[0]->type }
sub is_unknown { local $^W; UNKNOWN == $_[0]->type }
sub is_longlink { local $^W; LONGLINK eq $_[0]->type }
sub is_label { local $^W; LABEL eq $_[0]->type }
1;