std::size_t PipeIODevice::onEndRead(EventLoop& loop, char* buffer, std::size_t n, bool& eof)
{
loop.selector().disable(_ioh);
DWORD readBytes = 0;
DWORD flags = 0;
eof = false;
// TODO: can we receive EOF?
if (_bufferSize)
{
readBytes = _bufferSize;
}
else if ( FALSE == ReadMsgQueue(handle(), &_buffer[0], _msgSize, &readBytes, INFINITE, &flags) )
{
throw IOError( PT_ERROR_MSG("Could not read from message queue handle") );
}
DWORD bytesToCopy = std::min<DWORD>(_rbuflen, readBytes);
memcpy(_rbuf, &_buffer[0], bytesToCopy);
_bufferSize = 0;
if (_rbuflen >= readBytes)
return readBytes;
std::vector<char>::iterator beginData = (_buffer.begin() + bytesToCopy);
std::vector<char>::iterator endData = (_buffer.begin() + readBytes);
std::copy(beginData, endData, _buffer.begin());
_bufferSize = (readBytes - bytesToCopy);
return bytesToCopy;
}
std::size_t PipeIODevice::onBeginWrite(EventLoop& loop, const char* buffer, std::size_t n)
{
if( Write != _mode )
{
throw IOError( PT_ERROR_MSG("Could not write on a read only pipe") );
}
loop.selector().enable(_ioh);
return 0;
}
std::size_t PipeIODevice::onBeginRead(EventLoop& loop, char* buffer, std::size_t n, bool& eof)
{
if( Read != _mode )
throw IOError( PT_ERROR_MSG("Could not read from write only pipe") );
if(_bufferSize)
return std::min(_bufferSize, n);
loop.selector().enable(_ioh);
return 0;
}
std::size_t PipeIODevice::onEndWrite(EventLoop& loop, const char* buffer, std::size_t n)
{
loop.selector().disable(_ioh);
DWORD bytesToWrite = std::min<DWORD>(_wbuflen, _msgSize);
if ( FALSE == WriteMsgQueue(handle(), (LPVOID) _wbuf, bytesToWrite, 0, 0))
{
throw IOError( PT_ERROR_MSG("WriteMsgQueue failed") );
}
return bytesToWrite;
}
