def KMSGPollThreadProc():
"""
Logs Kernel messages starting with EtherCAT
Uses GLibc wrapper to Linux syscall "klogctl"
Last 4 KB are polled, and lines compared to last
captured line to detect new lines
"""
libc = ctypes.CDLL("libc.so.6")
klog = libc.klogctl
klog.argtypes = [ctypes.c_int, ctypes.c_char_p, ctypes.c_int]
klog.restype = ctypes.c_int
s = ctypes.create_string_buffer(4 * 1024)
last = None
while not StopKMSGThread:
bytes_to_read = klog(3, s, len(s) - 1)
log = s.value[:bytes_to_read - 1]
if last:
log = log.rpartition(last)[2]
if log:
last = log.rpartition('\n')[2]
for lvl, msg in re.findall(
r'<(\d)>\[\s*\d*\.\d*\]\s*(EtherCAT\s*.*)$', log,
re.MULTILINE):
PLCObject.LogMessage(
LogLevelsDict[{
"4": "WARNING",
"3": "CRITICAL"
}.get(lvl, "DEBUG")], msg)
time.sleep(0.5)
def SDOThreadProc(*params):
global Result, SDOProc
if params[0] == "upload":
cmdfmt = "ethercat upload -p %d -t %s 0x%.4x 0x%.2x"
else:
cmdfmt = "ethercat download -p %d -t %s 0x%.4x 0x%.2x %s"
command = cmdfmt % params[1:]
SDOProc = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True)
res = SDOProc.wait()
output = SDOProc.communicate()[0]
if params[0] == "upload":
Result = None
if res == 0:
if params[2] in ["float", "double"]:
Result = float(output)
elif params[2] in ["string", "octet_string", "unicode_string"]:
Result = output
else:
hex_value, dec_value = output.split()
if int(hex_value, 16) == int(dec_value):
Result = int(dec_value)
else:
Result = res == 0
SDOAnswered()
if res != 0:
PLCObject.LogMessage(LogLevelsDict["WARNING"],
"%s : %s" % (command, output))