function _openAppend() {
if (filesize($this->_tarname) == 0) {
return $this
->_openWrite();
}
if ($this->_compress) {
$this
->_close();
if (!@rename($this->_tarname, $this->_tarname . ".tmp")) {
$this
->_error('Error while renaming \'' . $this->_tarname . '\' to temporary file \'' . $this->_tarname . '.tmp\'');
return false;
}
if ($this->_compress_type == 'gz') {
$v_temp_tar = @gzopen($this->_tarname . ".tmp", "rb");
}
elseif ($this->_compress_type == 'bz2') {
$v_temp_tar = @bzopen($this->_tarname . ".tmp", "r");
}
if ($v_temp_tar == 0) {
$this
->_error('Unable to open file \'' . $this->_tarname . '.tmp\' in binary read mode');
@rename($this->_tarname . ".tmp", $this->_tarname);
return false;
}
if (!$this
->_openWrite()) {
@rename($this->_tarname . ".tmp", $this->_tarname);
return false;
}
if ($this->_compress_type == 'gz') {
while (!@gzeof($v_temp_tar)) {
$v_buffer = @gzread($v_temp_tar, 512);
if ($v_buffer == ARCHIVE_TAR_END_BLOCK) {
// do not copy end blocks, we will re-make them
// after appending
continue;
}
$v_binary_data = pack("a512", $v_buffer);
$this
->_writeBlock($v_binary_data);
}
@gzclose($v_temp_tar);
}
elseif ($this->_compress_type == 'bz2') {
while (strlen($v_buffer = @bzread($v_temp_tar, 512)) > 0) {
if ($v_buffer == ARCHIVE_TAR_END_BLOCK) {
continue;
}
$v_binary_data = pack("a512", $v_buffer);
$this
->_writeBlock($v_binary_data);
}
@bzclose($v_temp_tar);
}
if (!@drupal_unlink($this->_tarname . ".tmp")) {
$this
->_error('Error while deleting temporary file \'' . $this->_tarname . '.tmp\'');
}
}
else {
// ----- For not compressed tar, just add files before the last
// one or two 512 bytes block
if (!$this
->_openReadWrite()) {
return false;
}
clearstatcache(TRUE, $this->_tarname);
$v_size = filesize($this->_tarname);
// We might have zero, one or two end blocks.
// The standard is two, but we should try to handle
// other cases.
fseek($this->_file, $v_size - 1024);
if (fread($this->_file, 512) == ARCHIVE_TAR_END_BLOCK) {
fseek($this->_file, $v_size - 1024);
}
elseif (fread($this->_file, 512) == ARCHIVE_TAR_END_BLOCK) {
fseek($this->_file, $v_size - 512);
}
}
return true;
}