/**
* @coroutine
*
* @param int $maxSize Max frame size.
* @param float|int $timeout
*
* @return \Generator
*
* @resolve \Icicle\WebSocket\Protocol\Rfc6455Frame
*
* @throws \Icicle\WebSocket\Exception\FrameException
*/
public function read(int $maxSize, float $timeout = 0) : \Generator
{
$buffer = new Buffer();
try {
do {
$buffer->push(yield from $this->socket->read(0, null, $timeout));
} while ($buffer->getLength() < 2);
$bytes = unpack('Cflags/Clength', $buffer->shift(2));
$rsv = $bytes['flags'] & self::RSV_MASK;
$opcode = $bytes['flags'] & self::OPCODE_MASK;
$final = (bool) ($bytes['flags'] & self::FIN_MASK);
$masked = (bool) ($bytes['length'] & self::MASK_FLAG_MASK);
$size = $bytes['length'] & self::LENGTH_MASK;
if ($masked === $this->masked) {
throw new FrameException(sprintf('Received %s frame.', $masked ? 'masked' : 'unmasked'));
}
if ($size === self::TWO_BYTE_LENGTH_FLAG) {
while ($buffer->getLength() < 2) {
$buffer->push(yield from $this->socket->read(0, null, $timeout));
}
$bytes = unpack('nlength', $buffer->shift(2));
$size = $bytes['length'];
if ($size < self::TWO_BYTE_LENGTH_FLAG) {
throw new FrameException('Frame format error.');
}
} elseif ($size === self::EIGHT_BYTE_LENGTH_FLAG) {
while ($buffer->getLength() < 8) {
$buffer->push(yield from $this->socket->read(0, null, $timeout));
}
$bytes = unpack('Nhigh/Nlow', $buffer->shift(8));
$size = $bytes['high'] << 32 | $bytes['low'];
if ($size < self::TWO_BYTE_MAX_LENGTH) {
throw new FrameException('Frame format error.');
}
}
if ($size > $maxSize) {
throw new PolicyException('Frame size exceeded max allowed size.');
}
if ($masked) {
while ($buffer->getLength() < self::MASK_LENGTH) {
$buffer->push(yield from $this->socket->read(0, null, $timeout));
}
$mask = $buffer->shift(self::MASK_LENGTH);
}
while ($buffer->getLength() < $size) {
$buffer->push(yield from $this->socket->read(0, null, $timeout));
}
$data = $buffer->shift($size);
if ($masked) {
$data ^= str_repeat($mask, (int) (($size + self::MASK_LENGTH - 1) / self::MASK_LENGTH));
}
} finally {
if (!$buffer->isEmpty()) {
$this->socket->unshift((string) $buffer);
}
}
return new Frame($opcode, $data, $rsv, $final);
}
/**
* Returns bytes from the buffer based on the current length or current search byte.
*
* @return string
*/
private function remove() : string
{
if (null !== $this->byte && false !== ($position = $this->buffer->search($this->byte))) {
if (0 === $this->length || $position < $this->length) {
return $this->buffer->shift($position + 1);
}
return $this->buffer->shift($this->length);
}
if (0 === $this->length) {
return $this->buffer->drain();
}
return $this->buffer->shift($this->length);
}
/**
* @coroutine
*
* Reads and parses characters from the stream according to a format.
*
* The format string is of the same format as `sscanf()`.
*
* @param string $format The parse format.
* @param float|int $timeout Number of seconds until the returned promise is rejected with a TimeoutException
* if no data is received. Use 0 for no timeout.
*
* @return \Generator
*
* @resolve array An array of parsed values.
*
* @throws \Icicle\Awaitable\Exception\TimeoutException If the operation times out.
* @throws \Icicle\Stream\Exception\UnreadableException If the stream is no longer readable.
* @throws \Icicle\Stream\Exception\ClosedException If the stream is unexpectedly closed.
*
* @see http://php.net/sscanf
*/
public function scan(string $format, float $timeout = 0) : \Generator
{
// Read from the stream chunk by chunk, attempting to satisfy the format
// string each time until the format successfully parses or the end of
// the stream is reached.
while (true) {
$result = sscanf((string) $this->buffer, $format . '%n');
$length = $result ? array_pop($result) : null;
// If the format string was satisfied, consume the used characters and
// return the parsed results.
if ($length !== null && $length < $this->buffer->getLength()) {
$this->buffer->shift($length);
return $result;
}
// Read more into the buffer if possible.
if ($this->stream->isReadable()) {
$this->buffer->push(yield from $this->stream->read(0, null, $timeout));
} else {
// Format string can't be satisfied.
return [];
}
}
}
/**
* @param \Icicle\Stream\Structures\Buffer $buffer
* @param \Icicle\Socket\Socket $socket
* @param float|int $timeout
*
* @return \Generator
*
* @throws \Icicle\Http\Exception\MessageException
* @throws \Icicle\Http\Exception\ParseException
*/
protected function readHeaders(Buffer $buffer, Socket $socket, float $timeout = 0) : \Generator
{
$size = 0;
$headers = [];
do {
while (false === ($position = $buffer->search("\r\n"))) {
if ($buffer->getLength() >= $this->maxSize) {
throw new MessageException(Response::REQUEST_HEADER_TOO_LARGE, sprintf('Message header exceeded maximum size of %d bytes.', $this->maxSize));
}
$buffer->push(yield from $socket->read(0, null, $timeout));
}
$length = $position + 2;
$line = $buffer->shift($length);
if (2 === $length) {
return $headers;
}
$size += $length;
$parts = explode(':', $line, 2);
if (2 !== count($parts)) {
throw new ParseException('Found header without colon.');
}
list($name, $value) = $parts;
$name = Message\decode($name);
$value = Message\decode(trim($value));
// No check for case as Message class will automatically combine similarly named headers.
if (!isset($headers[$name])) {
$headers[$name] = [$value];
} else {
$headers[$name][] = $value;
}
} while ($size < $this->maxSize);
throw new MessageException(Response::REQUEST_HEADER_TOO_LARGE, sprintf('Message header exceeded maximum size of %d bytes.', $this->maxSize));
}
