runtime/PLCObject.py
author Edouard Tisserant
Thu, 31 Mar 2011 19:09:49 +0200
changeset 592 c6408f92da0a
parent 504 688e84df3408
child 593 726f58cf97e3
permissions -rwxr-xr-x
Initial TIME support in debugger
#!/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
import ctypes, os, commands, types, sys
from datetime import timedelta as td
from targets.typemapping import SameEndianessTypeTranslator as TypeTranslator

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

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
        
        # 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 _GetMD5FileName(self):
        return os.path.join(self.workingdir, "lasttransferedPLC.md5")

    def _GetLibFileName(self):
        return os.path.join(self.workingdir,self.CurrentPLCFilename)


    def _LoadNewPLC(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]
                
                self._stopPLC = self._stopPLC_real
            else:
                # If python plugin is not enabled, we reuse _PythonIterator
                # as a call that block pythonthread until StopPLC 
                self.PythonIteratorLock = Lock()
                self.PythonIteratorLock.acquire()
                def PythonIterator(res):
                    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 = None
            self._suspendDebug.argtypes = [ctypes.c_int]

            self._resumeDebug = self.PLClibraryHandle.resumeDebug
            self._resumeDebug.restype = None
            
            return True
        except:
            PLCprint(traceback.format_exc())
            return False

    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: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:None
        self._resumeDebug = lambda:None
        self._PythonIterator = lambda:""
        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 PrepareRuntimePy(self):
        self.python_threads_vars = globals().copy()
        self.python_threads_vars["WorkingDir"] = self.workingdir
        self.python_threads_vars["website"] = self.website
        self.python_threads_vars["_runtime_begin"] = []
        self.python_threads_vars["_runtime_cleanup"] = []
        
        for filename in os.listdir(self.workingdir):
            name, ext = os.path.splitext(filename)
            if name.upper().startswith("RUNTIME") and ext.upper() == ".PY":
                try:
                    # TODO handle exceptions in runtime.py
                    # pyfile may redefine _runtime_cleanup
                    # or even call _PythonThreadProc itself.
                    execfile(os.path.join(self.workingdir, filename), self.python_threads_vars)
                except:
                    PLCprint(traceback.format_exc())
                runtime_begin = self.python_threads_vars.get("_%s_begin" % name, None)
                if runtime_begin is not None:
                    self.python_threads_vars["_runtime_begin"].append(runtime_begin)
                runtime_cleanup = self.python_threads_vars.get("_%s_cleanup" % name, None)
                if runtime_cleanup is not None:
                    self.python_threads_vars["_runtime_cleanup"].append(runtime_cleanup)
        
        for runtime_begin in self.python_threads_vars.get("_runtime_begin", []):
            runtime_begin()
            
        if self.website is not None:
            self.website.PLCStarted()

    def FinishRuntimePy(self):
        for runtime_cleanup in self.python_threads_vars.get("_runtime_cleanup", []):
            runtime_cleanup()    
        if self.website is not None:
            self.website.PLCStopped()
        self.python_threads_vars = None

    def PythonThreadProc(self):
        c_argv = ctypes.c_char_p * len(self.argv)
        error = None
        if self._LoadNewPLC():
            if self._startPLC(len(self.argv),c_argv(*self.argv)) == 0:
                self.PLCStatus = "Started"
                self.StatusChange()
                self.evaluator(self.PrepareRuntimePy)
                res,cmd = "None","None"
                while True:
                    #print "_PythonIterator(", res, ")",
                    cmd = self._PythonIterator(res)
                    #print " -> ", cmd
                    if cmd is None:
                        break
                    try :
                        res = str(self.evaluator(eval,cmd,self.python_threads_vars))
                    except Exception,e:
                        res = "#EXCEPTION : "+str(e)
                        PLCprint(res)
                self.PLCStatus = "Stopped"
                self.StatusChange()
                self.evaluator(self.FinishRuntimePy)
            else:
                error = "starting"
        else:
            error = "loading"
        if error is not None:
            PLCprint("Problem %s PLC"%error)
            self.PLCStatus = "Broken"
        self._FreePLC()
    
    def StartPLC(self):
        PLCprint("StartPLC")
        if self.CurrentPLCFilename is not None and self.PLCStatus == "Stopped":
            self.PLCStatus = "Started"
            self.PythonThread = Thread(target=self.PythonThreadProc)
            self.PythonThread.start()
            
    def StopPLC(self):
        PLCprint("StopPLC")
        if self.PLCStatus == "Started":
            self.PLCStatus = "Stopped"
            self._stopPLC()
            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
    
    def NewPLC(self, md5sum, data, extrafiles):
        PLCprint("NewPLC (%s)"%md5sum)
        if self.PLCStatus in ["Stopped", "Empty", "Broken"]:
            NewFileName = md5sum + lib_ext
            extra_files_log = os.path.join(self.workingdir,"extra_files.txt")
            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:
                PLCprint(traceback.format_exc())
                return False
            if self.PLCStatus == "Empty":
                self.PLCStatus = "Stopped"
            return True
        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
            self._suspendDebug(False)
            # 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 = \
                        self.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":
            res=[]
            tick = ctypes.c_uint32()
            size = ctypes.c_uint32()
            buffer = ctypes.c_void_p()
            offset = 0
            if self.PLClibraryLock.acquire(False) and \
               self._GetDebugData(ctypes.byref(tick),
                                  ctypes.byref(size),
                                  ctypes.byref(buffer)) == 0 :
                if size.value:
                    for idx, iectype, forced in self._Idxs:
                        cursor = ctypes.c_void_p(buffer.value + offset)
                        c_type,unpack_func, pack_func = \
                            self.TypeTranslator.get(iectype,
                                                    (None,None,None))
                        if c_type is not None and offset < size.value:
                            res.append(unpack_func(
                                        ctypes.cast(cursor,
                                         ctypes.POINTER(c_type)).contents))
                            offset += ctypes.sizeof(c_type)
                        else:
                            if c_type is None:
                                PLCprint("Debug error - " + iectype +
                                         " not supported !")
                            #if offset >= size.value:
                                #PLCprint("Debug error - buffer too small ! %d != %d"%(offset, size.value))
                            break
                self._FreeDebugData()
                self.PLClibraryLock.release()
            if offset and offset == size.value:
                return self.PLCStatus, tick.value, res
            #elif size.value:
                #PLCprint("Debug error - wrong buffer unpack ! %d != %d"%(offset, size.value))
        return self.PLCStatus, None, []