/**
* Returns the recognized MIME type/description of the given file. The type
* is determined by the content using magic bytes characteristic for the
* particular file type.
*
* If the type could not be found, the function returns the default value,
* or <var>null</var>.
*
* @param string $filename The file path whose type to determine.
* @param string $default The default value.
* @return string|false
*/
public function getMimeType($filename, $default = null)
{
$reader = new HausDesign_Io_FileReader($filename);
$parentOffset = 0;
foreach (preg_split('/^/m', $this->_magic) as $line) {
$chunks = array();
if (!preg_match("/^(?P<Dependant>>?)(?P<Byte>\\d+)\\s+(?P<MatchType" . ">\\S+)\\s+(?P<MatchData>\\S+)(?:\\s+(?P<MIMEType>[a-" . "z]+\\/[a-z-0-9]+)?(?:\\s+(?P<Description>.?+))?)?\$/", $line, $chunks)) {
continue;
}
if ($chunks['Dependant']) {
$reader->setOffset($parentOffset);
$reader->skip($chunks['Byte']);
} else {
$reader->setOffset($parentOffset = $chunks['Byte']);
}
$matchType = strtolower($chunks['MatchType']);
$matchData = preg_replace(array("/\\\\ /", "/\\\\\\\\/", "/\\\\([0-7]{1,3})/e", "/\\\\x([0-9A-Fa-f]{1,2})/e", "/0x([0-9A-Fa-f]+)/e"), array(" ", "\\\\", "pack(\"H*\", base_convert(\"\$1\", 8, 16));", "pack(\"H*\", \"\$1\");", "hexdec(\"\$1\");"), $chunks["MatchData"]);
switch ($matchType) {
case 'byte':
// single character
$data = $reader->readInt8();
break;
case 'short':
// machine-order 16-bit integer
$data = $reader->readInt16();
break;
case 'long':
// machine-order 32-bit integer
$data = $reader->readInt32();
break;
case 'string':
// arbitrary-length string
$data = $reader->readString8(strlen($matchData));
break;
case 'date':
// long integer date (seconds since Unix epoch)
$data = $reader->readInt64BE();
break;
case 'beshort':
// big-endian 16-bit integer
$data = $reader->readUInt16BE();
break;
case 'belong':
// big-endian 32-bit integer
// break intentionally omitted
// big-endian 32-bit integer
// break intentionally omitted
case 'bedate':
// big-endian 32-bit integer date
$data = $reader->readUInt32BE();
break;
case 'leshort':
// little-endian 16-bit integer
$data = $reader->readUInt16LE();
break;
case 'lelong':
// little-endian 32-bit integer
// break intentionally omitted
// little-endian 32-bit integer
// break intentionally omitted
case 'ledate':
// little-endian 32-bit integer date
$data = $reader->readUInt32LE();
break;
default:
$data = null;
break;
}
if (strcmp($data, $matchData) == 0) {
if (!empty($chunks['MIMEType'])) {
return $chunks['MIMEType'];
}
if (!empty($chunks['Description'])) {
return rtrim($chunks['Description'], "\n");
}
}
}
return $default;
}
