/**
* This function will read a full WebSocketFrame from the connection
* that was passed as the first parameter. Keep calling this function
* untill the frame has been read completely because a frame might
* need to be read in parts from the socket.
*
* @param WebSocketConnection $pConnection The WebSocketConnection from which to read the frame
*/
public function read(WebSocketConnection $pConnection)
{
/* If we haven't read the first 2 bytes and the read-buffer is smaller
* then 2 bytes, wait for the next round and hope the bytes will be
* available then. */
if (!$this->m_bFirstBytesRead && $pConnection->getReadBufferSize() < 2) {
return true;
}
/* At this point we are sure there are at least 2 bytes in the read-buffer,
* so we can start by reading the first 2 if we haven't already done that.
* I'll refer to these two bytes as header*/
if (!$this->m_bFirstBytesRead) {
/* Read the two bytes */
$nData = $pConnection->read(2);
$this->m_bFirstBytesRead = true;
/* Extract the values from the bytes using bit-wise operations.
* Point 4.2 of the protocol goes more into details as to how
* WebSocket Frames are formed */
$this->m_bFinal = (0x80 & $nData[0]) == 0x80 ? true : false;
$this->m_nRsv = (0x70 & $nData[0]) >> 4;
$this->m_nType = 0xf & $nData[0];
$this->m_bMasked = (0x80 & $nData[1]) == 0x80 ? true : false;
$this->m_nPayLoadLength = 0x7f & $nData[1];
}
/* If the payloadlength in the header is 126, the actual payload length
* is in the next two bytes. So read those. If the value in the header
* is 127, the actual payloadlength is in the next 8 bytes. */
if (!$this->m_bLengthRead && $this->m_nPayLoadLength == 126) {
if ($pConnection->getReadBufferSize() >= 2) {
$this->m_nPayLoadLength = $this->repack($pConnection->read(2));
$this->m_bLengthRead = true;
}
} elseif (!$this->m_bLengthRead && $this->m_nPayLoadLength == 127) {
if ($pConnection->getReadBufferSize() >= 8) {
$this->m_nPayLoadLength = $this->repack($pConnection->read(8));
$this->m_bLengthRead = true;
}
} else {
/* Or the payloadlength in the header was the actual payloadlength */
$this->m_bLengthRead = true;
}
/* If the payloadlength is larger then WebSocketFrame :: m_nMaxLengthIn we can't process it properly */
if ($this->m_nPayLoadLength > static::$m_nMaxLengthIn) {
return false;
}
/* The header contains a masking-bit. When this bit is set, the next 4 bytes are a
* masking key that is used to mask the payloaddata using XOR encryption. */
if (!$this->m_bMaskingKeyRead && $this->m_bMasked && count($this->m_aMaskingKey) == 0) {
if ($pConnection->getReadBufferSize() >= 4) {
$this->m_aMaskingKey = $pConnection->read(4);
$this->m_bMaskingKeyRead = true;
}
}
/* If there is enough data in the read-buffer, read the data. */
if ($pConnection->getReadBufferSize() >= $this->m_nPayLoadLength) {
$this->m_aData = $pConnection->read($this->m_nPayLoadLength);
/* If the masking bit is set, unmask the data using the masking-key we
* read from the stream earlier. */
if ($this->m_bMasked) {
$this->unMask();
}
/* At this point the frame has been read completely */
$this->m_bIsComplete = true;
} else {
/* The frame is not complete yet */
$this->m_bIsComplete = false;
}
/* Nothing went wrong! YEEY! */
return true;
}
