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package Archive::Zip::ZipFileMember;
use strict;
use vars qw( $VERSION @ISA );
BEGIN {
$VERSION = '1.60';
@ISA = qw ( Archive::Zip::FileMember );
}
use Archive::Zip qw(
:CONSTANTS
:ERROR_CODES
:PKZIP_CONSTANTS
:UTILITY_METHODS
);
# Create a new Archive::Zip::ZipFileMember
# given a filename and optional open file handle
#
sub _newFromZipFile {
my $class = shift;
my $fh = shift;
my $externalFileName = shift;
my $possibleEocdOffset = shift; # normally 0
my $self = $class->new(
'crc32' => 0,
'diskNumberStart' => 0,
'localHeaderRelativeOffset' => 0,
'dataOffset' => 0, # localHeaderRelativeOffset + header length
@_
);
$self->{'externalFileName'} = $externalFileName;
$self->{'fh'} = $fh;
$self->{'possibleEocdOffset'} = $possibleEocdOffset;
return $self;
}
sub isDirectory {
my $self = shift;
return (substr($self->fileName, -1, 1) eq '/'
and $self->uncompressedSize == 0);
}
# Seek to the beginning of the local header, just past the signature.
# Verify that the local header signature is in fact correct.
# Update the localHeaderRelativeOffset if necessary by adding the possibleEocdOffset.
# Returns status.
sub _seekToLocalHeader {
my $self = shift;
my $where = shift; # optional
my $previousWhere = shift; # optional
$where = $self->localHeaderRelativeOffset() unless defined($where);
# avoid loop on certain corrupt files (from Julian Field)
return _formatError("corrupt zip file")
if defined($previousWhere) && $where == $previousWhere;
my $status;
my $signature;
$status = $self->fh()->seek($where, IO::Seekable::SEEK_SET);
return _ioError("seeking to local header") unless $status;
($status, $signature) =
_readSignature($self->fh(), $self->externalFileName(),
LOCAL_FILE_HEADER_SIGNATURE);
return $status if $status == AZ_IO_ERROR;
# retry with EOCD offset if any was given.
if ($status == AZ_FORMAT_ERROR && $self->{'possibleEocdOffset'}) {
$status = $self->_seekToLocalHeader(
$self->localHeaderRelativeOffset() + $self->{'possibleEocdOffset'},
$where
);
if ($status == AZ_OK) {
$self->{'localHeaderRelativeOffset'} +=
$self->{'possibleEocdOffset'};
$self->{'possibleEocdOffset'} = 0;
}
}
return $status;
}
# Because I'm going to delete the file handle, read the local file
# header if the file handle is seekable. If it is not, I assume that
# I've already read the local header.
# Return ( $status, $self )
sub _become {
my $self = shift;
my $newClass = shift;
return $self if ref($self) eq $newClass;
my $status = AZ_OK;
if (_isSeekable($self->fh())) {
my $here = $self->fh()->tell();
$status = $self->_seekToLocalHeader();
$status = $self->_readLocalFileHeader() if $status == AZ_OK;
$self->fh()->seek($here, IO::Seekable::SEEK_SET);
return $status unless $status == AZ_OK;
}
delete($self->{'eocdCrc32'});
delete($self->{'diskNumberStart'});
delete($self->{'localHeaderRelativeOffset'});
delete($self->{'dataOffset'});
return $self->SUPER::_become($newClass);
}
sub diskNumberStart {
shift->{'diskNumberStart'};
}
sub localHeaderRelativeOffset {
shift->{'localHeaderRelativeOffset'};
}
sub dataOffset {
shift->{'dataOffset'};
}
# Skip local file header, updating only extra field stuff.
# Assumes that fh is positioned before signature.
sub _skipLocalFileHeader {
my $self = shift;
my $header;
my $bytesRead = $self->fh()->read($header, LOCAL_FILE_HEADER_LENGTH);
if ($bytesRead != LOCAL_FILE_HEADER_LENGTH) {
return _ioError("reading local file header");
}
my $fileNameLength;
my $extraFieldLength;
my $bitFlag;
(
undef, # $self->{'versionNeededToExtract'},
$bitFlag,
undef, # $self->{'compressionMethod'},
undef, # $self->{'lastModFileDateTime'},
undef, # $crc32,
undef, # $compressedSize,
undef, # $uncompressedSize,
$fileNameLength,
$extraFieldLength
) = unpack(LOCAL_FILE_HEADER_FORMAT, $header);
if ($fileNameLength) {
$self->fh()->seek($fileNameLength, IO::Seekable::SEEK_CUR)
or return _ioError("skipping local file name");
}
if ($extraFieldLength) {
$bytesRead =
$self->fh()->read($self->{'localExtraField'}, $extraFieldLength);
if ($bytesRead != $extraFieldLength) {
return _ioError("reading local extra field");
}
}
$self->{'dataOffset'} = $self->fh()->tell();
if ($bitFlag & GPBF_HAS_DATA_DESCRIPTOR_MASK) {
# Read the crc32, compressedSize, and uncompressedSize from the
# extended data descriptor, which directly follows the compressed data.
#
# Skip over the compressed file data (assumes that EOCD compressedSize
# was correct)
$self->fh()->seek($self->{'compressedSize'}, IO::Seekable::SEEK_CUR)
or return _ioError("seeking to extended local header");
# these values should be set correctly from before.
my $oldCrc32 = $self->{'eocdCrc32'};
my $oldCompressedSize = $self->{'compressedSize'};
my $oldUncompressedSize = $self->{'uncompressedSize'};
my $status = $self->_readDataDescriptor();
return $status unless $status == AZ_OK;
# The buffer withe encrypted data is prefixed with a new
# encrypted 12 byte header. The size only changes when
# the buffer is also compressed
$self->isEncrypted && $oldUncompressedSize > $self->{uncompressedSize}
and $oldUncompressedSize -= DATA_DESCRIPTOR_LENGTH;
return _formatError(
"CRC or size mismatch while skipping data descriptor")
if ( $oldCrc32 != $self->{'crc32'}
|| $oldUncompressedSize != $self->{'uncompressedSize'});
$self->{'crc32'} = 0
if $self->compressionMethod() == COMPRESSION_STORED ;
}
return AZ_OK;
}
# Read from a local file header into myself. Returns AZ_OK if successful.
# Assumes that fh is positioned after signature.
# Note that crc32, compressedSize, and uncompressedSize will be 0 if
# GPBF_HAS_DATA_DESCRIPTOR_MASK is set in the bitFlag.
sub _readLocalFileHeader {
my $self = shift;
my $header;
my $bytesRead = $self->fh()->read($header, LOCAL_FILE_HEADER_LENGTH);
if ($bytesRead != LOCAL_FILE_HEADER_LENGTH) {
return _ioError("reading local file header");
}
my $fileNameLength;
my $crc32;
my $compressedSize;
my $uncompressedSize;
my $extraFieldLength;
(
$self->{'versionNeededToExtract'}, $self->{'bitFlag'},
$self->{'compressionMethod'}, $self->{'lastModFileDateTime'},
$crc32, $compressedSize,
$uncompressedSize, $fileNameLength,
$extraFieldLength
) = unpack(LOCAL_FILE_HEADER_FORMAT, $header);
if ($fileNameLength) {
my $fileName;
$bytesRead = $self->fh()->read($fileName, $fileNameLength);
if ($bytesRead != $fileNameLength) {
return _ioError("reading local file name");
}
$self->fileName($fileName);
}
if ($extraFieldLength) {
$bytesRead =
$self->fh()->read($self->{'localExtraField'}, $extraFieldLength);
if ($bytesRead != $extraFieldLength) {
return _ioError("reading local extra field");
}
}
$self->{'dataOffset'} = $self->fh()->tell();
if ($self->hasDataDescriptor()) {
# Read the crc32, compressedSize, and uncompressedSize from the
# extended data descriptor.
# Skip over the compressed file data (assumes that EOCD compressedSize
# was correct)
$self->fh()->seek($self->{'compressedSize'}, IO::Seekable::SEEK_CUR)
or return _ioError("seeking to extended local header");
my $status = $self->_readDataDescriptor();
return $status unless $status == AZ_OK;
} else {
return _formatError(
"CRC or size mismatch after reading data descriptor")
if ( $self->{'crc32'} != $crc32
|| $self->{'uncompressedSize'} != $uncompressedSize);
}
return AZ_OK;
}
# This will read the data descriptor, which is after the end of compressed file
# data in members that have GPBF_HAS_DATA_DESCRIPTOR_MASK set in their bitFlag.
# The only reliable way to find these is to rely on the EOCD compressedSize.
# Assumes that file is positioned immediately after the compressed data.
# Returns status; sets crc32, compressedSize, and uncompressedSize.
sub _readDataDescriptor {
my $self = shift;
my $signatureData;
my $header;
my $crc32;
my $compressedSize;
my $uncompressedSize;
my $bytesRead = $self->fh()->read($signatureData, SIGNATURE_LENGTH);
return _ioError("reading header signature")
if $bytesRead != SIGNATURE_LENGTH;
my $signature = unpack(SIGNATURE_FORMAT, $signatureData);
# unfortunately, the signature appears to be optional.
if ($signature == DATA_DESCRIPTOR_SIGNATURE
&& ($signature != $self->{'crc32'})) {
$bytesRead = $self->fh()->read($header, DATA_DESCRIPTOR_LENGTH);
return _ioError("reading data descriptor")
if $bytesRead != DATA_DESCRIPTOR_LENGTH;
($crc32, $compressedSize, $uncompressedSize) =
unpack(DATA_DESCRIPTOR_FORMAT, $header);
} else {
$bytesRead = $self->fh()->read($header, DATA_DESCRIPTOR_LENGTH_NO_SIG);
return _ioError("reading data descriptor")
if $bytesRead != DATA_DESCRIPTOR_LENGTH_NO_SIG;
$crc32 = $signature;
($compressedSize, $uncompressedSize) =
unpack(DATA_DESCRIPTOR_FORMAT_NO_SIG, $header);
}
$self->{'eocdCrc32'} = $self->{'crc32'}
unless defined($self->{'eocdCrc32'});
$self->{'crc32'} = $crc32;
$self->{'compressedSize'} = $compressedSize;
$self->{'uncompressedSize'} = $uncompressedSize;
return AZ_OK;
}
# Read a Central Directory header. Return AZ_OK on success.
# Assumes that fh is positioned right after the signature.
sub _readCentralDirectoryFileHeader {
my $self = shift;
my $fh = $self->fh();
my $header = '';
my $bytesRead = $fh->read($header, CENTRAL_DIRECTORY_FILE_HEADER_LENGTH);
if ($bytesRead != CENTRAL_DIRECTORY_FILE_HEADER_LENGTH) {
return _ioError("reading central dir header");
}
my ($fileNameLength, $extraFieldLength, $fileCommentLength);
(
$self->{'versionMadeBy'},
$self->{'fileAttributeFormat'},
$self->{'versionNeededToExtract'},
$self->{'bitFlag'},
$self->{'compressionMethod'},
$self->{'lastModFileDateTime'},
$self->{'crc32'},
$self->{'compressedSize'},
$self->{'uncompressedSize'},
$fileNameLength,
$extraFieldLength,
$fileCommentLength,
$self->{'diskNumberStart'},
$self->{'internalFileAttributes'},
$self->{'externalFileAttributes'},
$self->{'localHeaderRelativeOffset'}
) = unpack(CENTRAL_DIRECTORY_FILE_HEADER_FORMAT, $header);
$self->{'eocdCrc32'} = $self->{'crc32'};
if ($fileNameLength) {
$bytesRead = $fh->read($self->{'fileName'}, $fileNameLength);
if ($bytesRead != $fileNameLength) {
_ioError("reading central dir filename");
}
}
if ($extraFieldLength) {
$bytesRead = $fh->read($self->{'cdExtraField'}, $extraFieldLength);
if ($bytesRead != $extraFieldLength) {
return _ioError("reading central dir extra field");
}
}
if ($fileCommentLength) {
$bytesRead = $fh->read($self->{'fileComment'}, $fileCommentLength);
if ($bytesRead != $fileCommentLength) {
return _ioError("reading central dir file comment");
}
}
# NK 10/21/04: added to avoid problems with manipulated headers
if ( $self->{'uncompressedSize'} != $self->{'compressedSize'}
and $self->{'compressionMethod'} == COMPRESSION_STORED) {
$self->{'uncompressedSize'} = $self->{'compressedSize'};
}
$self->desiredCompressionMethod($self->compressionMethod());
return AZ_OK;
}
sub rewindData {
my $self = shift;
my $status = $self->SUPER::rewindData(@_);
return $status unless $status == AZ_OK;
return AZ_IO_ERROR unless $self->fh();
$self->fh()->clearerr();
# Seek to local file header.
# The only reason that I'm doing this this way is that the extraField
# length seems to be different between the CD header and the LF header.
$status = $self->_seekToLocalHeader();
return $status unless $status == AZ_OK;
# skip local file header
$status = $self->_skipLocalFileHeader();
return $status unless $status == AZ_OK;
# Seek to beginning of file data
$self->fh()->seek($self->dataOffset(), IO::Seekable::SEEK_SET)
or return _ioError("seeking to beginning of file data");
return AZ_OK;
}
# Return bytes read. Note that first parameter is a ref to a buffer.
# my $data;
# my ( $bytesRead, $status) = $self->readRawChunk( \$data, $chunkSize );
sub _readRawChunk {
my ($self, $dataRef, $chunkSize) = @_;
return (0, AZ_OK) unless $chunkSize;
my $bytesRead = $self->fh()->read($$dataRef, $chunkSize)
or return (0, _ioError("reading data"));
return ($bytesRead, AZ_OK);
}
1;