Handle new lockfile versions in nsmd 1.6.0. Will still work in older versions

engine/nsmservercontrol.py

@@ -41,6 +41,7 @@ from uuid import uuid4
 from datetime import datetime
 from sys import exit as sysexit
 from time import sleep
+from ctypes import c_ulong
 
 #Our files
 from .comparedirectories import md5_dir
@@ -316,7 +317,7 @@ class NsmServerControl(object):
         #Deactivate hooks for now. During init no hooks may be called,
         #but some functions want to do that already. We setup the true hooks at the end of init
         self.sessionOpenReadyHook= self.sessionOpenLoadingHook= self.sessionClosedHook= self.clientStatusHook= self.singleInstanceActivateWindowHook= self.dataClientNamesHook= self.dataClientDescriptionHook= nothing
-
+        self.lockfile_directory = getenv("XDG_RUNTIME_DIR")
         self._queue = list() #Incoming OSC messages are buffered here.
 
         #Status variables that are set by our callbacks
@@ -1413,10 +1414,39 @@ class NsmServerControl(object):
                 return True
         return False
 
+
+    def _simple_hash(self, s:str) -> int:
+        """This is a translation from the nsm/file.c function of the same name.
+        We use it to find the lock file on our system.
+
+        It is a djb2 hash modulo 65521
+        """
+        hashAddress = 5381
+        for i, char in enumerate(s):
+            hashAddress = ((hashAddress << 5) + hashAddress ) + ord(char)
+
+        hashAddress = c_ulong(hashAddress).value #wrap around for whatever number of bits unsinged long is on this system. 2**64 most likely
+        return hashAddress % 65521
+
+
+    def _get_lock_file_name(self, session_name:str, full_absolute_session_path:str) -> pathlib.Path:
+        """This is a translation from the nsm/nsmd.c function of the same name.
+        We use it to find the lock file on our system.
+
+        To avoid collisions of two simple session names under either different subdirs or even
+        different session roots."""
+        #session_name in Agordejo includes subdirs. We want only the basename, like in nsmd. Luckily they are paths.
+        session_name = pathlib.Path(session_name).name #basename
+        session_hash:int = self._simple_hash(full_absolute_session_path)
+        session_lock = pathlib.Path(self.lockfile_directory, "nsm", session_name + str(session_hash))
+        return session_lock
+
+
     def _checkIfLocked(self, nsmSessionName:str)->bool:
-        basePath = pathlib.Path(self.sessionRoot, nsmSessionName)
-        assert basePath.exists()
-        lockFile = pathlib.Path(basePath, ".lock")
+        #basePath = pathlib.Path(self.sessionRoot, nsmSessionName)
+        #assert basePath.exists()
+        #lockFile = pathlib.Path(basePath, ".lock")
+        lockFile = self._get_lock_file_name(nsmSessionName, str(pathlib.Path(self.sessionRoot, nsmSessionName)))
         return lockFile.exists()
 
     def getSessionFiles(self, nsmSessionName:str)->list:

engine/watcher.py

@@ -155,7 +155,7 @@ class Watcher(object):
 
                 #Lockfiles
                 if self.lockFileHook:
-                    lockfileState = entry["lockFile"].is_file()
+                    lockfileState = self._nsmServerControl._checkIfLocked(nsmSessionName)
                     if not self._lastLockfile[nsmSessionName] == lockfileState:
                         self._lastLockfile[nsmSessionName] = lockfileState
                         self.lockFileHook(nsmSessionName, lockfileState)
@@ -168,6 +168,3 @@ class Watcher(object):
                 logger.warning(f"File not found error for {entry}")
                 self._lastExport.remove(entry) #avoid stumbling upon this again
                 self._update()
-
-
-

qtgui/sessiontreecontroller.py

@@ -98,16 +98,12 @@ class SessionItem(QtWidgets.QTreeWidgetItem):
 
     def setLocked(self, state:bool):
         """Number of clients, symlinks and size change frequently while a session is open/locked.
-        We deactivate the display of these values while locked"""
-        return
-        if not state == self.isDisabled():
-            self.setDisabled(state)
-            if state:
-                self.setText(2, "") #number of clients
-                self.setText(3, "") #Symlinks
-                self.setText(4, "") #Size
-            else:
-                self.updateData()
+        We deactivate the display of these values while locked
+
+        This is also used for nsmd lockfiles and locked sessions, aka session open by another nsmd.
+        """
+        self.updateData()
+        self.setDisabled(state)
 
     def updateTimestamp(self, timestamp:str):
         #Column 1 "Last Save"
@@ -282,7 +278,7 @@ class SessionTreeController(object):
         listOfLabelsAndFunctions = [
             (QtCore.QCoreApplication.translate("SessionTree", "Copy Session"), lambda: self._askForCopyAndCopy(item.sessionDict["nsmSessionName"]))
             ]
-        if not item.isDisabled():
+        if not item.isDisabled() and not item.sessionDict["locked"]:
             listOfLabelsAndFunctions.append((QtCore.QCoreApplication.translate("SessionTree", "Rename Session"), lambda: self._askForNameAndRenameSession(item.sessionDict["nsmSessionName"])))
             #Delete should be the bottom item.
             listOfLabelsAndFunctions.append((QtCore.QCoreApplication.translate("SessionTree", "Delete Session"), lambda: self.deleteSessionItem(item)))
@@ -310,7 +306,6 @@ class SessionTreeController(object):
     def _reactSelectionChanged(self, item, previous):
         """User clicks on an entry in the session chooser, or in the empty space.
         in any case, the selection changes and we can decide if we activate/deactivate certain buttons"""
-
         if not item or not type(item) is SessionItem or item.sessionDict["locked"] == True:
             sessionSelectedState = False
         else: