beremiz

modbus extension code cleanup, from smarteh's patch

2018-01-30, Edouard Tisserant
338e2f51b685
file isExecutable
modbus extension code cleanup, from smarteh's patch
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This file is part of Beremiz runtime.
#
# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
#
# See COPYING.Runtime file for copyrights details.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
from __future__ import absolute_import
from threading import Timer, Thread, Lock, Semaphore, Event
import ctypes
import os
import sys
import traceback
from time import time
import Pyro.core as pyro
from runtime.typemapping import TypeTranslator
from runtime.loglevels import LogLevelsDefault, LogLevelsCount
if os.name in ("nt", "ce"):
from _ctypes import LoadLibrary as dlopen
from _ctypes import FreeLibrary as dlclose
elif os.name == "posix":
from _ctypes import dlopen, dlclose
def get_last_traceback(tb):
while tb.tb_next:
tb = tb.tb_next
return tb
lib_ext = {
"linux2": ".so",
"win32": ".dll",
}.get(sys.platform, "")
def PLCprint(message):
sys.stdout.write("PLCobject : "+message+"\n")
sys.stdout.flush()
class PLCObject(pyro.ObjBase):
def __init__(self, workingdir, daemon, argv, statuschange, evaluator, pyruntimevars):
pyro.ObjBase.__init__(self)
self.evaluator = evaluator
self.argv = [workingdir] + argv # force argv[0] to be "path" to exec...
self.workingdir = workingdir
self.PLCStatus = "Empty"
self.PLClibraryHandle = None
self.PLClibraryLock = Lock()
self.DummyIteratorLock = None
# Creates fake C funcs proxies
self._FreePLC()
self.daemon = daemon
self.statuschange = statuschange
self.hmi_frame = None
self.pyruntimevars = pyruntimevars
self._loading_error = None
self.python_runtime_vars = None
self.TraceThread = None
self.TraceLock = Lock()
self.TraceWakeup = Event()
self.Traces = []
def AutoLoad(self):
# Get the last transfered PLC if connector must be restart
try:
self.CurrentPLCFilename = open(
self._GetMD5FileName(),
"r").read().strip() + lib_ext
if self.LoadPLC():
self.PLCStatus = "Stopped"
except Exception:
self.PLCStatus = "Empty"
self.CurrentPLCFilename = None
def StatusChange(self):
if self.statuschange is not None:
for callee in self.statuschange:
callee(self.PLCStatus)
def LogMessage(self, *args):
if len(args) == 2:
level, msg = args
else:
level = LogLevelsDefault
msg, = args
PLCprint(msg)
if self._LogMessage is not None:
return self._LogMessage(level, msg, len(msg))
return None
def ResetLogCount(self):
if self._ResetLogCount is not None:
self._ResetLogCount()
def GetLogCount(self, level):
if self._GetLogCount is not None:
return int(self._GetLogCount(level))
elif self._loading_error is not None and level == 0:
return 1
def GetLogMessage(self, level, msgid):
tick = ctypes.c_uint32()
tv_sec = ctypes.c_uint32()
tv_nsec = ctypes.c_uint32()
if self._GetLogMessage is not None:
maxsz = len(self._log_read_buffer)-1
sz = self._GetLogMessage(level, msgid,
self._log_read_buffer, maxsz,
ctypes.byref(tick),
ctypes.byref(tv_sec),
ctypes.byref(tv_nsec))
if sz and sz <= maxsz:
self._log_read_buffer[sz] = '\x00'
return self._log_read_buffer.value, tick.value, tv_sec.value, tv_nsec.value
elif self._loading_error is not None and level == 0:
return self._loading_error, 0, 0, 0
return None
def _GetMD5FileName(self):
return os.path.join(self.workingdir, "lasttransferedPLC.md5")
def _GetLibFileName(self):
return os.path.join(self.workingdir, self.CurrentPLCFilename)
def LoadPLC(self):
"""
Load PLC library
Declare all functions, arguments and return values
"""
md5 = open(self._GetMD5FileName(), "r").read()
try:
self._PLClibraryHandle = dlopen(self._GetLibFileName())
self.PLClibraryHandle = ctypes.CDLL(self.CurrentPLCFilename, handle=self._PLClibraryHandle)
self.PLC_ID = ctypes.c_char_p.in_dll(self.PLClibraryHandle, "PLC_ID")
if len(md5) == 32:
self.PLC_ID.value = md5
self._startPLC = self.PLClibraryHandle.startPLC
self._startPLC.restype = ctypes.c_int
self._startPLC.argtypes = [ctypes.c_int, ctypes.POINTER(ctypes.c_char_p)]
self._stopPLC_real = self.PLClibraryHandle.stopPLC
self._stopPLC_real.restype = None
self._PythonIterator = getattr(self.PLClibraryHandle, "PythonIterator", None)
if self._PythonIterator is not None:
self._PythonIterator.restype = ctypes.c_char_p
self._PythonIterator.argtypes = [ctypes.c_char_p, ctypes.POINTER(ctypes.c_void_p)]
self._stopPLC = self._stopPLC_real
else:
# If python confnode is not enabled, we reuse _PythonIterator
# as a call that block pythonthread until StopPLC
self.PlcStopping = Event()
def PythonIterator(res, blkid):
self.PlcStopping.clear()
self.PlcStopping.wait()
return None
self._PythonIterator = PythonIterator
def __StopPLC():
self._stopPLC_real()
self.PlcStopping.set()
self._stopPLC = __StopPLC
self._ResetDebugVariables = self.PLClibraryHandle.ResetDebugVariables
self._ResetDebugVariables.restype = None
self._RegisterDebugVariable = self.PLClibraryHandle.RegisterDebugVariable
self._RegisterDebugVariable.restype = None
self._RegisterDebugVariable.argtypes = [ctypes.c_int, ctypes.c_void_p]
self._FreeDebugData = self.PLClibraryHandle.FreeDebugData
self._FreeDebugData.restype = None
self._GetDebugData = self.PLClibraryHandle.GetDebugData
self._GetDebugData.restype = ctypes.c_int
self._GetDebugData.argtypes = [ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(ctypes.c_void_p)]
self._suspendDebug = self.PLClibraryHandle.suspendDebug
self._suspendDebug.restype = ctypes.c_int
self._suspendDebug.argtypes = [ctypes.c_int]
self._resumeDebug = self.PLClibraryHandle.resumeDebug
self._resumeDebug.restype = None
self._ResetLogCount = self.PLClibraryHandle.ResetLogCount
self._ResetLogCount.restype = None
self._GetLogCount = self.PLClibraryHandle.GetLogCount
self._GetLogCount.restype = ctypes.c_uint32
self._GetLogCount.argtypes = [ctypes.c_uint8]
self._LogMessage = self.PLClibraryHandle.LogMessage
self._LogMessage.restype = ctypes.c_int
self._LogMessage.argtypes = [ctypes.c_uint8, ctypes.c_char_p, ctypes.c_uint32]
self._log_read_buffer = ctypes.create_string_buffer(1 << 14) # 16K
self._GetLogMessage = self.PLClibraryHandle.GetLogMessage
self._GetLogMessage.restype = ctypes.c_uint32
self._GetLogMessage.argtypes = [ctypes.c_uint8, ctypes.c_uint32, ctypes.c_char_p, ctypes.c_uint32, ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(ctypes.c_uint32)]
self._loading_error = None
self.PythonRuntimeInit()
return True
except Exception:
self._loading_error = traceback.format_exc()
PLCprint(self._loading_error)
return False
def UnLoadPLC(self):
self.PythonRuntimeCleanup()
self._FreePLC()
def _FreePLC(self):
"""
Unload PLC library.
This is also called by __init__ to create dummy C func proxies
"""
self.PLClibraryLock.acquire()
# Forget all refs to library
self._startPLC = lambda x, y: None
self._stopPLC = lambda: None
self._ResetDebugVariables = lambda: None
self._RegisterDebugVariable = lambda x, y: None
self._IterDebugData = lambda x, y: None
self._FreeDebugData = lambda: None
self._GetDebugData = lambda: -1
self._suspendDebug = lambda x: -1
self._resumeDebug = lambda: None
self._PythonIterator = lambda: ""
self._GetLogCount = None
self._LogMessage = None
self._GetLogMessage = None
self.PLClibraryHandle = None
# Unload library explicitely
if getattr(self, "_PLClibraryHandle", None) is not None:
dlclose(self._PLClibraryHandle)
self._PLClibraryHandle = None
self.PLClibraryLock.release()
return False
def PythonRuntimeCall(self, methodname):
"""
Calls init, start, stop or cleanup method provided by
runtime python files, loaded when new PLC uploaded
"""
for method in self.python_runtime_vars.get("_runtime_%s" % methodname, []):
_res, exp = self.evaluator(method)
if exp is not None:
self.LogMessage(0, '\n'.join(traceback.format_exception(*exp)))
def PythonRuntimeInit(self):
MethodNames = ["init", "start", "stop", "cleanup"]
self.python_runtime_vars = globals().copy()
self.python_runtime_vars.update(self.pyruntimevars)
parent = self
class PLCSafeGlobals(object):
def __getattr__(self, name):
try:
t = parent.python_runtime_vars["_"+name+"_ctype"]
except KeyError:
raise KeyError("Try to get unknown shared global variable : %s" % name)
v = t()
parent.python_runtime_vars["_PySafeGetPLCGlob_"+name](ctypes.byref(v))
return parent.python_runtime_vars["_"+name+"_unpack"](v)
def __setattr__(self, name, value):
try:
t = parent.python_runtime_vars["_"+name+"_ctype"]
except KeyError:
raise KeyError("Try to set unknown shared global variable : %s" % name)
v = parent.python_runtime_vars["_"+name+"_pack"](t, value)
parent.python_runtime_vars["_PySafeSetPLCGlob_"+name](ctypes.byref(v))
self.python_runtime_vars.update({
"PLCGlobals": PLCSafeGlobals(),
"WorkingDir": self.workingdir,
"PLCObject": self,
"PLCBinary": self.PLClibraryHandle,
"PLCGlobalsDesc": []})
for methodname in MethodNames:
self.python_runtime_vars["_runtime_%s" % methodname] = []
try:
filenames = os.listdir(self.workingdir)
filenames.sort()
for filename in filenames:
name, ext = os.path.splitext(filename)
if name.upper().startswith("RUNTIME") and ext.upper() == ".PY":
execfile(os.path.join(self.workingdir, filename), self.python_runtime_vars)
for methodname in MethodNames:
method = self.python_runtime_vars.get("_%s_%s" % (name, methodname), None)
if method is not None:
self.python_runtime_vars["_runtime_%s" % methodname].append(method)
except Exception:
self.LogMessage(0, traceback.format_exc())
raise
self.PythonRuntimeCall("init")
def PythonRuntimeCleanup(self):
if self.python_runtime_vars is not None:
self.PythonRuntimeCall("cleanup")
self.python_runtime_vars = None
def PythonThreadProc(self):
self.StartSem.release()
res, cmd, blkid = "None", "None", ctypes.c_void_p()
compile_cache = {}
while True:
# print "_PythonIterator(", res, ")",
cmd = self._PythonIterator(res, blkid)
FBID = blkid.value
# print " -> ", cmd, blkid
if cmd is None:
break
try:
self.python_runtime_vars["FBID"] = FBID
ccmd, AST = compile_cache.get(FBID, (None, None))
if ccmd is None or ccmd != cmd:
AST = compile(cmd, '<plc>', 'eval')
compile_cache[FBID] = (cmd, AST)
result, exp = self.evaluator(eval, AST, self.python_runtime_vars)
if exp is not None:
res = "#EXCEPTION : "+str(exp[1])
self.LogMessage(1, ('PyEval@0x%x(Code="%s") Exception "%s"') % (
FBID, cmd, '\n'.join(traceback.format_exception(*exp))))
else:
res = str(result)
self.python_runtime_vars["FBID"] = None
except Exception, e:
res = "#EXCEPTION : "+str(e)
self.LogMessage(1, ('PyEval@0x%x(Code="%s") Exception "%s"') % (FBID, cmd, str(e)))
def StartPLC(self):
if self.CurrentPLCFilename is not None and self.PLCStatus == "Stopped":
c_argv = ctypes.c_char_p * len(self.argv)
res = self._startPLC(len(self.argv), c_argv(*self.argv))
if res == 0:
self.PLCStatus = "Started"
self.StatusChange()
self.PythonRuntimeCall("start")
self.StartSem = Semaphore(0)
self.PythonThread = Thread(target=self.PythonThreadProc)
self.PythonThread.start()
self.StartSem.acquire()
self.LogMessage("PLC started")
else:
self.LogMessage(0, _("Problem starting PLC : error %d" % res))
self.PLCStatus = "Broken"
self.StatusChange()
def StopPLC(self):
if self.PLCStatus == "Started":
self.LogMessage("PLC stopped")
self._stopPLC()
self.PythonThread.join()
self.PLCStatus = "Stopped"
self.StatusChange()
self.PythonRuntimeCall("stop")
if self.TraceThread is not None:
self.TraceWakeup.set()
self.TraceThread.join()
self.TraceThread = None
return True
return False
def _Reload(self):
self.daemon.shutdown(True)
self.daemon.sock.close()
os.execv(sys.executable, [sys.executable]+sys.argv[:])
# never reached
return 0
def ForceReload(self):
# respawn python interpreter
Timer(0.1, self._Reload).start()
return True
def GetPLCstatus(self):
return self.PLCStatus, map(self.GetLogCount, xrange(LogLevelsCount))
def NewPLC(self, md5sum, data, extrafiles):
if self.PLCStatus in ["Stopped", "Empty", "Broken"]:
NewFileName = md5sum + lib_ext
extra_files_log = os.path.join(self.workingdir, "extra_files.txt")
self.UnLoadPLC()
self.LogMessage("NewPLC (%s)" % md5sum)
self.PLCStatus = "Empty"
try:
os.remove(os.path.join(self.workingdir,
self.CurrentPLCFilename))
for filename in file(extra_files_log, "r").readlines() + [extra_files_log]:
try:
os.remove(os.path.join(self.workingdir, filename.strip()))
except Exception:
pass
except Exception:
pass
try:
# Create new PLC file
open(os.path.join(self.workingdir, NewFileName),
'wb').write(data)
# Store new PLC filename based on md5 key
open(self._GetMD5FileName(), "w").write(md5sum)
# Then write the files
log = file(extra_files_log, "w")
for fname, fdata in extrafiles:
fpath = os.path.join(self.workingdir, fname)
open(fpath, "wb").write(fdata)
log.write(fname+'\n')
# Store new PLC filename
self.CurrentPLCFilename = NewFileName
except Exception:
self.PLCStatus = "Broken"
self.StatusChange()
PLCprint(traceback.format_exc())
return False
if self.LoadPLC():
self.PLCStatus = "Stopped"
else:
self.PLCStatus = "Broken"
self._FreePLC()
self.StatusChange()
return self.PLCStatus == "Stopped"
return False
def MatchMD5(self, MD5):
try:
last_md5 = open(self._GetMD5FileName(), "r").read()
return last_md5 == MD5
except Exception:
pass
return False
def SetTraceVariablesList(self, idxs):
"""
Call ctype imported function to append
these indexes to registred variables in PLC debugger
"""
if idxs:
# suspend but dont disable
if self._suspendDebug(False) == 0:
# keep a copy of requested idx
self._ResetDebugVariables()
for idx, iectype, force in idxs:
if force is not None:
c_type, _unpack_func, pack_func = \
TypeTranslator.get(iectype,
(None, None, None))
force = ctypes.byref(pack_func(c_type, force))
self._RegisterDebugVariable(idx, force)
self._TracesSwap()
self._resumeDebug()
else:
self._suspendDebug(True)
def _TracesPush(self, trace):
self.TraceLock.acquire()
lT = len(self.Traces)
if lT != 0 and lT * len(self.Traces[0]) > 1024 * 1024:
self.Traces.pop(0)
self.Traces.append(trace)
self.TraceLock.release()
def _TracesSwap(self):
self.LastSwapTrace = time()
if self.TraceThread is None and self.PLCStatus == "Started":
self.TraceThread = Thread(target=self.TraceThreadProc)
self.TraceThread.start()
self.TraceLock.acquire()
Traces = self.Traces
self.Traces = []
self.TraceLock.release()
self.TraceWakeup.set()
return Traces
def _TracesAutoSuspend(self):
# TraceProc stops here if Traces not polled for 3 seconds
traces_age = time() - self.LastSwapTrace
if traces_age > 3:
self.TraceLock.acquire()
self.Traces = []
self.TraceLock.release()
self._suspendDebug(True) # Disable debugger
self.TraceWakeup.clear()
self.TraceWakeup.wait()
self._resumeDebug() # Re-enable debugger
def _TracesFlush(self):
self.TraceLock.acquire()
self.Traces = []
self.TraceLock.release()
def GetTraceVariables(self):
return self.PLCStatus, self._TracesSwap()
def TraceThreadProc(self):
"""
Return a list of traces, corresponding to the list of required idx
"""
while self.PLCStatus == "Started":
tick = ctypes.c_uint32()
size = ctypes.c_uint32()
buff = ctypes.c_void_p()
TraceBuffer = None
if self.PLClibraryLock.acquire(False):
if self._GetDebugData(ctypes.byref(tick),
ctypes.byref(size),
ctypes.byref(buff)) == 0:
if size.value:
TraceBuffer = ctypes.string_at(buff.value, size.value)
self._FreeDebugData()
self.PLClibraryLock.release()
if TraceBuffer is not None:
self._TracesPush((tick.value, TraceBuffer))
self._TracesAutoSuspend()
self._TracesFlush()
def RemoteExec(self, script, *kwargs):
try:
exec script in kwargs
except Exception:
_e_type, e_value, e_traceback = sys.exc_info()
line_no = traceback.tb_lineno(get_last_traceback(e_traceback))
return (-1, "RemoteExec script failed!\n\nLine %d: %s\n\t%s" %
(line_no, e_value, script.splitlines()[line_no - 1]))
return (0, kwargs.get("returnVal", None))