bool Connection::sendOutgoingMessage(MessageID messageID, PassOwnPtr<ArgumentEncoder> arguments)
{
ASSERT(m_socket);
// We put the message ID last.
arguments->encodeUInt32(messageID.toInt());
size_t bufferSize = arguments->bufferSize();
// Write message size first
// FIXME: Should just do a single write.
qint64 bytesWrittenForSize = m_socket->write(reinterpret_cast<char*>(&bufferSize), sizeof(bufferSize));
if (bytesWrittenForSize != sizeof(bufferSize)) {
connectionDidClose();
return false;
}
qint64 bytesWrittenForBuffer = m_socket->write(reinterpret_cast<char*>(arguments->buffer()), arguments->bufferSize());
if (bytesWrittenForBuffer != arguments->bufferSize()) {
connectionDidClose();
return false;
}
m_socket->flush();
return true;
}
void Connection::readyReadHandler()
{
while (true) {
size_t fileDescriptorsCount = 0;
size_t bytesToRead = m_readBuffer.size() - m_readBufferSize;
ssize_t bytesRead = readBytesFromSocket(m_socketDescriptor, m_readBuffer.data() + m_readBufferSize, bytesToRead,
m_fileDescriptors.data() + m_fileDescriptorsSize, &fileDescriptorsCount);
if (bytesRead < 0) {
// EINTR was already handled by readBytesFromSocket.
if (errno == EAGAIN || errno == EWOULDBLOCK)
return;
WTFLogAlways("Error receiving IPC message on socket %d in process %d: %s", m_socketDescriptor, getpid(), strerror(errno));
connectionDidClose();
return;
}
m_readBufferSize += bytesRead;
m_fileDescriptorsSize += fileDescriptorsCount;
if (!bytesRead) {
connectionDidClose();
return;
}
// Process messages from data received.
while (true) {
if (!processMessage())
break;
}
}
}
void Connection::writeEventHandler()
{
if (m_connectionPipe == INVALID_HANDLE_VALUE)
return;
DWORD numberOfBytesWritten = 0;
if (!::GetOverlappedResult(m_connectionPipe, &m_writeState, &numberOfBytesWritten, FALSE)) {
DWORD error = ::GetLastError();
if (error == ERROR_IO_INCOMPLETE) {
// FIXME: We should figure out why we're getting this error.
return;
}
if (error == ERROR_BROKEN_PIPE) {
connectionDidClose();
return;
}
ASSERT_NOT_REACHED();
}
// The pending write has finished, so we are now done with its encoder. Clearing this member
// will allow us to send messages again.
m_pendingWriteEncoder = nullptr;
// Now that the pending write has finished, we can try to send a new message.
sendOutgoingMessages();
}
void Connection::exceptionSourceEventHandler()
{
ReceiveBuffer buffer;
mach_msg_header_t* header = readFromMachPort(m_exceptionPort, buffer);
if (!header)
return;
// We've read the exception message. Now send it on to the real exception port.
// The remote port should have a send once right.
ASSERT(MACH_MSGH_BITS_REMOTE(header->msgh_bits) == MACH_MSG_TYPE_MOVE_SEND_ONCE);
// Now get the real exception port.
mach_port_t exceptionPort = machExceptionPort();
// First, get the complex bit from the source message.
mach_msg_bits_t messageBits = header->msgh_bits & MACH_MSGH_BITS_COMPLEX;
messageBits |= MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, MACH_MSG_TYPE_MOVE_SEND_ONCE);
header->msgh_bits = messageBits;
header->msgh_local_port = header->msgh_remote_port;
header->msgh_remote_port = exceptionPort;
// Now send along the message.
kern_return_t kr = mach_msg(header, MACH_SEND_MSG, header->msgh_size, 0, MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
if (kr != KERN_SUCCESS) {
LOG_ERROR("Failed to send message to real exception port. %s (%x)", mach_error_string(kr), kr);
ASSERT_NOT_REACHED();
}
connectionDidClose();
}
void Connection::readyReadHandler()
{
while (true) {
size_t fileDescriptorsCount = 0;
size_t bytesToRead = m_readBuffer.size() - m_readBufferSize;
ssize_t bytesRead = readBytesFromSocket(m_socketDescriptor, m_readBuffer.data() + m_readBufferSize, bytesToRead,
m_fileDescriptors.data() + m_fileDescriptorsSize, &fileDescriptorsCount);
if (bytesRead < 0) {
// EINTR was already handled by readBytesFromSocket.
if (errno == EAGAIN || errno == EWOULDBLOCK)
return;
// FIXME: Handle other errors here?
return;
}
m_readBufferSize += bytesRead;
m_fileDescriptorsSize += fileDescriptorsCount;
if (!bytesRead) {
connectionDidClose();
return;
}
// Process messages from data received.
while (true) {
if (!processMessage())
break;
}
}
}
void ChildProcessProxy::clearConnection()
{
if (!m_connection)
return;
// FIXME: Call this after the connection has been invalidated.
connectionDidClose(*m_connection);
m_connection->invalidate();
m_connection = nullptr;
}
bool Connection::sendOutgoingMessage(MessageID messageID, PassOwnPtr<MessageEncoder> encoder)
{
ASSERT(!m_pendingWriteEncoder);
// Just bail if the handle has been closed.
if (m_connectionPipe == INVALID_HANDLE_VALUE)
return false;
// We put the message ID last.
encoder->encode(static_cast<uint32_t>(messageID.toInt()));
// Write the outgoing message.
if (::WriteFile(m_connectionPipe, encoder->buffer(), encoder->bufferSize(), 0, &m_writeState)) {
// We successfully sent this message.
return true;
}
DWORD error = ::GetLastError();
if (error == ERROR_NO_DATA) {
// The pipe is being closed.
connectionDidClose();
return false;
}
if (error != ERROR_IO_PENDING) {
ASSERT_NOT_REACHED();
return false;
}
// The message will be sent soon. Hold onto the encoder so that it won't be destroyed
// before the write completes.
m_pendingWriteEncoder = encoder;
// We can only send one asynchronous message at a time (see comment in platformCanSendOutgoingMessages).
return false;
}
void Connection::readEventHandler()
{
if (m_connectionPipe == INVALID_HANDLE_VALUE)
return;
while (true) {
// Check if we got some data.
DWORD numberOfBytesRead = 0;
if (!::GetOverlappedResult(m_connectionPipe, &m_readState, &numberOfBytesRead, FALSE)) {
DWORD error = ::GetLastError();
switch (error) {
case ERROR_BROKEN_PIPE:
connectionDidClose();
return;
case ERROR_MORE_DATA: {
// Read the rest of the message out of the pipe.
DWORD bytesToRead = 0;
if (!::PeekNamedPipe(m_connectionPipe, 0, 0, 0, 0, &bytesToRead)) {
DWORD error = ::GetLastError();
if (error == ERROR_BROKEN_PIPE) {
connectionDidClose();
return;
}
ASSERT_NOT_REACHED();
return;
}
// ::GetOverlappedResult told us there's more data. ::PeekNamedPipe shouldn't
// contradict it!
ASSERT(bytesToRead);
if (!bytesToRead)
break;
m_readBuffer.grow(m_readBuffer.size() + bytesToRead);
if (!::ReadFile(m_connectionPipe, m_readBuffer.data() + numberOfBytesRead, bytesToRead, 0, &m_readState)) {
DWORD error = ::GetLastError();
ASSERT_NOT_REACHED();
return;
}
continue;
}
// FIXME: We should figure out why we're getting this error.
case ERROR_IO_INCOMPLETE:
return;
default:
ASSERT_NOT_REACHED();
}
}
if (!m_readBuffer.isEmpty()) {
// We have a message, let's dispatch it.
// The messageID is encoded at the end of the buffer.
// Note that we assume here that the message is the same size as m_readBuffer. We can
// assume this because we always size m_readBuffer to exactly match the size of the message,
// either when receiving ERROR_MORE_DATA from ::GetOverlappedResult above or when
// ::PeekNamedPipe tells us the size below. We never set m_readBuffer to a size larger
// than the message.
ASSERT(m_readBuffer.size() >= sizeof(MessageID));
size_t realBufferSize = m_readBuffer.size() - sizeof(MessageID);
unsigned messageID = *reinterpret_cast<unsigned*>(m_readBuffer.data() + realBufferSize);
OwnPtr<MessageDecoder> decoder = MessageDecoder::create(DataReference(m_readBuffer.data(), realBufferSize));
processIncomingMessage(MessageID::fromInt(messageID), decoder.release());
}
// Find out the size of the next message in the pipe (if there is one) so that we can read
// it all in one operation. (This is just an optimization to avoid an extra pass through the
// loop (if we chose a buffer size that was too small) or allocating extra memory (if we
// chose a buffer size that was too large).)
DWORD bytesToRead = 0;
if (!::PeekNamedPipe(m_connectionPipe, 0, 0, 0, 0, &bytesToRead)) {
DWORD error = ::GetLastError();
if (error == ERROR_BROKEN_PIPE) {
connectionDidClose();
return;
}
ASSERT_NOT_REACHED();
}
if (!bytesToRead) {
// There's no message waiting in the pipe. Schedule a read of the first byte of the
// next message. We'll find out the message's actual size when it arrives. (If we
// change this to read more than a single byte for performance reasons, we'll have to
// deal with m_readBuffer potentially being larger than the message we read after
// calling ::GetOverlappedResult above.)
bytesToRead = 1;
}
m_readBuffer.resize(bytesToRead);
// Either read the next available message (which should occur synchronously), or start an
// asynchronous read of the next message that becomes available.
BOOL result = ::ReadFile(m_connectionPipe, m_readBuffer.data(), m_readBuffer.size(), 0, &m_readState);
if (result) {
// There was already a message waiting in the pipe, and we read it synchronously.
// Process it.
continue;
}
DWORD error = ::GetLastError();
if (error == ERROR_IO_PENDING) {
// There are no messages in the pipe currently. readEventHandler will be called again once there is a message.
return;
}
if (error == ERROR_MORE_DATA) {
// Either a message is available when we didn't think one was, or the message is larger
// than ::PeekNamedPipe told us. The former seems far more likely. Probably the message
// became available between our calls to ::PeekNamedPipe and ::ReadFile above. Go back
// to the top of the loop to use ::GetOverlappedResult to retrieve the available data.
continue;
}
// FIXME: We need to handle other errors here.
ASSERT_NOT_REACHED();
}
}