/**
* Sends the specified content as a file to the browser.
*
* Note that this method only prepares the response for file sending. The file is not sent
* until {@see \rock\response\Response::send()} is called explicitly or implicitly. The latter is done after you return from a controller action.
*
* @param string $content the content to be sent.
* The existing {@see \rock\response\Response::$content} will be discarded.
* @param string $attachmentName the file name shown to the user.
* @param array $options additional options for sending the file. The following options are supported:
*
* - `mimeType`: the MIME type of the content. Defaults to 'application/octet-stream'.
* - `inline`: boolean, whether the browser should open the file within the browser window. Defaults to false,
* meaning a download dialog will pop up.
*
* @return static the response object itself
* @throws ResponseException if the requested range is not satisfiable
*/
public function sendContentAsFile($content, $attachmentName, $options = [])
{
$headers = $this->getHeaders();
$contentLength = StringHelper::byteLength($content);
$range = $this->getHttpRange($contentLength);
if ($range === false) {
$headers->set('Content-Range', "bytes */{$contentLength}");
throw new ResponseException('Requested range not satisfiable');
}
$mimeType = isset($options['mimeType']) ? $options['mimeType'] : 'application/octet-stream';
$this->setDownloadHeaders($attachmentName, $mimeType, !empty($options['inline']), $contentLength);
list($begin, $end) = $range;
if ($begin != 0 || $end != $contentLength - 1) {
$this->setStatusCode(206);
$headers->set('Content-Range', "bytes {$begin}-{$end}/{$contentLength}");
$this->content = StringHelper::byteSubstr($content, $begin, $end - $begin + 1);
} else {
$this->setStatusCode(200);
$this->content = $content;
}
$this->format = self::FORMAT_RAW;
return $this;
}
/**
* Performs string comparison using timing attack resistant approach.
* @see http://codereview.stackexchange.com/questions/13512
* @param string $expected string to compare.
* @param string $actual user-supplied string.
* @return boolean whether strings are equal.
*/
public function compareString($expected, $actual)
{
$expected .= "";
$actual .= "";
$expectedLength = StringHelper::byteLength($expected);
$actualLength = StringHelper::byteLength($actual);
$diff = $expectedLength - $actualLength;
for ($i = 0; $i < $actualLength; $i++) {
$diff |= ord($actual[$i]) ^ ord($expected[$i % $expectedLength]);
}
return $diff === 0;
}