/**
* Calculate a hash of a Stream
*
* @param StreamInterface $stream Stream to calculate the hash for
* @param string $algo Hash algorithm (e.g. md5, crc32, etc)
* @param bool $rawOutput Whether or not to use raw output
*
* @return bool|string Returns false on failure or a hash string on success
*/
public static function getHash(StreamInterface $stream, $algo, $rawOutput = false)
{
$pos = $stream->ftell();
if (!$stream->seek(0)) {
return false;
}
$ctx = hash_init($algo);
while ($data = $stream->read(8192)) {
hash_update($ctx, $data);
}
$out = hash_final($ctx, (bool) $rawOutput);
$stream->seek($pos);
return $out;
}
/**
* {@inheritdoc}
*/
protected function doTell()
{
return $this->stream->ftell();
}
