def StatusCheckLoop(self):
hComm = self.hFile
waitingOnStatusHandle = False
dwCommEvent = DWORD()
dwOvRes = DWORD()
commMask = (
EV_BREAK | EV_CTS | EV_DSR | EV_ERR | EV_RING
| EV_RLSD | EV_RXCHAR | EV_RXFLAG | EV_TXEMPTY
)
if not SetCommMask(self.hFile, commMask):
raise SerialError("error setting communications mask")
osStatus = OVERLAPPED(0)
osStatus.hEvent = CreateEvent(None, 1, 0, None)
if not osStatus.hEvent:
raise SerialError("error creating event")
while True:
# Issue a status event check if one hasn't been issued already.
if not waitingOnStatusHandle:
if WaitCommEvent(hComm, byref(dwCommEvent), byref(osStatus)):
# WaitCommEvent returned immediately.
# Deal with status event as appropriate.
self.ReportStatusEvent(dwCommEvent.value)
else:
if GetLastError() == ERROR_IO_PENDING:
waitingOnStatusHandle = True
else:
raise SerialError("error in WaitCommEvent")
# Check on overlapped operation
if waitingOnStatusHandle:
# Wait a little while for an event to occur.
res = WaitForSingleObject(osStatus.hEvent, 1000)
if res == WAIT_OBJECT_0:
if GetOverlappedResult(
hComm, byref(osStatus), byref(dwOvRes), 0
):
# Status event is stored in the event flag
# specified in the original WaitCommEvent call.
# Deal with the status event as appropriate.
self.ReportStatusEvent(dwCommEvent.value)
else:
# An error occurred in the overlapped operation;
# call GetLastError to find out what it was
# and abort if it is fatal.
raise SerialError()
# Set waitingOnStatusHandle flag to indicate that a new
# WaitCommEvent is to be issued.
waitingOnStatusHandle = True
elif res == WAIT_TIMEOUT:
print "timeout"
else:
# This indicates a problem with the OVERLAPPED structure's
# event handle.
CloseHandle(osStatus.hEvent)
raise SerialError("error in the WaitForSingleObject")
CloseHandle(osStatus.hEvent)
def __init__(self, msg=None):
if msg is None:
errno = GetLastError()
strerror = FormatError(errno)
else:
errno = 0
strerror = msg
eg.Exception.__init__(self, errno, strerror)
def ReceiveThreadProc(self):
hFile = self.hFile
osReader = self.osReader
lpBuf = create_string_buffer(1)
dwRead = DWORD()
pHandles = (HANDLE * 2)(osReader.hEvent, self.stopEvent)
waitingOnRead = False
while self.keepAlive:
#print "ReceiveThreadProc"
# if no read is outstanding, then issue another one
if not waitingOnRead:
#print "ResetEvent"
ResetEvent(osReader.hEvent)
returnValue = self._ReadFile(
hFile,
lpBuf,
1, # we want to get notified as soon as a byte is available
byref(dwRead),
byref(osReader)
)
if not returnValue:
err = GetLastError()
if err != 0 and err != ERROR_IO_PENDING:
raise SerialError()
waitingOnRead = True
else:
# read completed immediately
if dwRead.value:
self.HandleReceive(lpBuf.raw)
continue
ret = MsgWaitForMultipleObjects(
2, pHandles, 0, 100000, QS_ALLINPUT
)
if ret == WAIT_OBJECT_0:
returnValue = GetOverlappedResult(
hFile,
byref(osReader),
byref(dwRead),
0
)
#print "GetOverlappedResult", returnValue, dwRead.value
waitingOnRead = False
if returnValue and dwRead.value:
self.HandleReceive(lpBuf.raw)
elif ret == WAIT_OBJECT_0 + 1:
#print "WAIT_OBJECT_1"
# stop event signaled
self.readCondition.acquire()
self.readCondition.notifyAll()
self.readCondition.release()
break
elif ret == WAIT_TIMEOUT:
#print "WAIT_TIMEOUT"
pass
else:
raise SerialError("Unknown message in ReceiveThreadProc")
def Write(self, data):
"""
Writes a string to the port.
"""
dwWritten = DWORD(0)
returnValue = self._WriteFile(self.hFile, data, len(data),
byref(dwWritten), byref(self.osWriter))
if returnValue != 0:
return
err = GetLastError()
if err != 0 and err != ERROR_IO_PENDING:
raise SerialError()
if not GetOverlappedResult(self.hFile, byref(self.osWriter),
byref(dwWritten), 1):
raise SerialError()
if dwWritten.value != len(data):
raise self.SerialError("Write timeout")
def GetAllPorts(cls):
"""
Returns a list with all available serial ports.
"""
serialPortList = cls._serialPortList
if serialPortList is not None:
return serialPortList
serialPortList = []
commconfig = COMMCONFIG()
commconfig.dwSize = sizeof(COMMCONFIG)
lpCC = pointer(commconfig)
dwSize = DWORD(0)
lpdwSize = byref(dwSize)
for i in range(0, 255):
name = 'COM%d' % (i + 1)
res = GetDefaultCommConfig(name, lpCC, lpdwSize)
if res == 1 or (res == 0 and GetLastError() == 122):
serialPortList.append(i)
cls._serialPortList = serialPortList
return serialPortList
