runtime/PLCObject.py
author Laurent Bessard
Tue, 30 Apr 2013 09:49:52 +0200
changeset 1080 5ec20f56b1d2
parent 1075 8078c01ae464
child 1093 b5f78cff4459
permissions -rwxr-xr-x
Fixed bug list of ConfNodes blocks not refreshed when a library was enable or disable
#!/usr/bin/env python
# -*- coding: utf-8 -*-

#This file is part of Beremiz, a Integrated Development Environment for
#programming IEC 61131-3 automates supporting plcopen standard and CanFestival. 
#
#Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
#
#See COPYING file for copyrights details.
#
#This library is free software; you can redistribute it and/or
#modify it under the terms of the GNU 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
#General Public License for more details.
#
#You should have received a copy of the GNU General Public
#License along with this library; if not, write to the Free Software
#Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import Pyro.core as pyro
from threading import Timer, Thread, Lock, Semaphore
import ctypes, os, commands, types, sys
from targets.typemapping import LogLevelsDefault, LogLevelsCount, TypeTranslator, UnpackDebugBuffer


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

import traceback
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):
    _Idxs = []
    def __init__(self, workingdir, daemon, argv, statuschange, evaluator, website):
        pyro.ObjBase.__init__(self)
        self.evaluator = evaluator
        self.argv = [workingdir] + argv # force argv[0] to be "path" to exec...
        self.workingdir = workingdir
        self.PLCStatus = "Stopped"
        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.website = website
        self._loading_error = None
        self.python_runtime_vars = None
        
        # Get the last transfered PLC if connector must be restart
        try:
            self.CurrentPLCFilename=open(
                             self._GetMD5FileName(),
                             "r").read().strip() + lib_ext
        except Exception, e:
            self.PLCStatus = "Empty"
            self.CurrentPLCFilename=None

    def StatusChange(self):
        if self.statuschange is not None:
            self.statuschange(self.PLCStatus)

    def LogMessage(self, *args):
        if len(args) == 2:
            level, msg = args
        else:
            level = LogLevelsDefault
            msg, = args
        return self._LogMessage(level, msg, len(msg))


    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
        """
        try:
            self._PLClibraryHandle = dlopen(self._GetLibFileName())
            self.PLClibraryHandle = ctypes.CDLL(self.CurrentPLCFilename, handle=self._PLClibraryHandle)
    
            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.PythonIteratorLock = Lock()
                self.PythonIteratorLock.acquire()
                def PythonIterator(res, blkid):
                    self.PythonIteratorLock.acquire()
                    self.PythonIteratorLock.release()
                    return None
                self._PythonIterator = PythonIterator
                
                def __StopPLC():
                    self._stopPLC_real()
                    self.PythonIteratorLock.release()
                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._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:
            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 = lambda l,m,s:PLCprint("OFF LOG :"+m)
        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["WorkingDir"] = self.workingdir
        self.python_runtime_vars["website"] = self.website
        for methodname in MethodNames :
            self.python_runtime_vars["_runtime_%s"%methodname] = []
        self.python_runtime_vars["PLCObject"] = self
        self.python_runtime_vars["PLCBinary"] = self.PLClibraryHandle
        
        try:
            for filename in os.listdir(self.workingdir):
                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:
            self.LogMessage(0,traceback.format_exc())
            raise
            
        self.PythonRuntimeCall("init")

        if self.website is not None:
            self.website.PLCStarted()


    def PythonRuntimeCleanup(self):
        if self.python_runtime_vars is not None:
            self.PythonRuntimeCall("cleanup")

        if self.website is not None:
            self.website.PLCStopped()

        self.python_runtime_vars = None

    def PythonThreadProc(self):
        self.PLCStatus = "Started"
        self.StatusChange()
        self.StartSem.release()
        self.PythonRuntimeCall("start")
        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,cmd,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)))
        self.PLCStatus = "Stopped"
        self.StatusChange()
        self.PythonRuntimeCall("stop")
    
    def StartPLC(self):
        if self.CurrentPLCFilename is not None and self.PLCStatus == "Stopped":
            c_argv = ctypes.c_char_p * len(self.argv)
            error = None
            res = self._startPLC(len(self.argv),c_argv(*self.argv))
            if res == 0:
                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()
            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:
                        pass
            except:
                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:
                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:
            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._Idxs = idxs[:]
                self._ResetDebugVariables()
                for idx,iectype,force in idxs:
                    if force !=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._resumeDebug()
        else:
            self._suspendDebug(True)
            self._Idxs =  []

    def GetTraceVariables(self):
        """
        Return a list of variables, corresponding to the list of required idx
        """
        if self.PLCStatus == "Started":
            tick = ctypes.c_uint32()
            size = ctypes.c_uint32()
            buff = ctypes.c_void_p()
            TraceVariables = None
            if self.PLClibraryLock.acquire(False):
                if self._GetDebugData(ctypes.byref(tick),
                                      ctypes.byref(size),
                                      ctypes.byref(buff)) == 0:
                    if size.value:
                        TraceVariables = UnpackDebugBuffer(buff, size.value, self._Idxs)
                    self._FreeDebugData()
                self.PLClibraryLock.release()
            if TraceVariables is not None:
                return self.PLCStatus, tick.value, TraceVariables
        return self.PLCStatus, None, []

    def RemoteExec(self, script, **kwargs):
        try:
            exec script in kwargs
        except:
            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))