tes, $index, 3));
return $node;
case 32:
$bytes = Util::read($this->fileHandle, $baseOffset + $index * 4, 4);
[, $node] = unpack('N', $bytes);
return $node;
default:
throw new InvalidDatabaseException(
'Unknown record size: '
. $this->metadata->recordSize
);
}
}
/**
* @return mixed
*/
private function resolveDataPointer(int $pointer)
{
$resolved = $pointer - $this->metadata->nodeCount
+ $this->metadata->searchTreeSize;
if ($resolved >= $this->fileSize) {
throw new InvalidDatabaseException(
"The MaxMind DB file's search tree is corrupt"
);
}
[$data] = $this->decoder->decode($resolved);
return $data;
}
/*
* This is an extremely naive but reasonably readable implementation. There
* are much faster algorithms (e.g., Boyer-Moore) for this if speed is ever
* an issue, but I suspect it won't be.
*/
private function findMetadataStart(string $filename): int
{
$handle = $this->fileHandle;
$fstat = fstat($handle);
$fileSize = $fstat['size'];
$marker = self::$METADATA_START_MARKER;
$markerLength = self::$METADATA_START_MARKER_LENGTH;
$minStart = $fileSize - min(self::$METADATA_MAX_SIZE, $fileSize);
for ($offset = $fileSize - $markerLength; $offset >= $minStart; --$offset) {
if (fseek($handle, $offset) !== 0) {
break;
}
$value = fread($handle, $markerLength);
if ($value === $marker) {
return $offset + $markerLength;
}
}
throw new InvalidDatabaseException(
"Error opening database file ($filename). " .
'Is this a valid MaxMind DB file?'
);
}
/**
* @throws InvalidArgumentException if arguments are passed to the method
* @throws BadMethodCallException if the database has been closed
*
* @return Metadata object for the database
*/
public function metadata(): Metadata
{
if (\func_num_args()) {
throw new ArgumentCountError(
sprintf('%s() expects exactly 0 parameters, %d given', __METHOD__, \func_num_args())
);
}
// Not technically required, but this makes it consistent with
// C extension and it allows us to change our implementation later.
if (!\is_resource($this->fileHandle)) {
throw new BadMethodCallException(
'Attempt to read from a closed MaxMind DB.'
);
}
return clone $this->metadata;
}
/**
* Closes the MaxMind DB and returns resources to the system.
*
* @throws Exception
* if an I/O error occurs
*/
public function close(): void
{
if (\func_num_args()) {
throw new ArgumentCountError(
sprintf('%s() expects exactly 0 parameters, %d given', __METHOD__, \func_num_args())
);
}
if (!\is_resource($this->fileHandle)) {
throw new BadMethodCallException(
'Attempt to close a closed MaxMind DB.'
);
}
fclose($this->fileHandle);
}
}
فروشگاه - گروه فنی مهندسی کوثر
