fuse mount: fix unlocking of repository at umount time, fixes #331

there were 2 issues:
lock used another pid and tid than release because daemonize() made it different processes/threads.
solved by just determining PID only once and not using TID any more.

the other issue was that the repo needed and explicit closing.

borg/archiver.py

@@ -348,18 +348,21 @@ Type "Yes I am sure" if you understand this and want to continue.\n""")
             return self.exit_code
 
         repository = self.open_repository(args.src)
-        manifest, key = Manifest.load(repository)
-        if args.src.archive:
-            archive = Archive(repository, key, manifest, args.src.archive)
-        else:
-            archive = None
-        operations = FuseOperations(key, repository, manifest, archive)
-        self.print_verbose("Mounting filesystem")
         try:
-            operations.mount(args.mountpoint, args.options, args.foreground)
-        except RuntimeError:
-            # Relevant error message already printed to stderr by fuse
-            self.exit_code = EXIT_ERROR
+            manifest, key = Manifest.load(repository)
+            if args.src.archive:
+                archive = Archive(repository, key, manifest, args.src.archive)
+            else:
+                archive = None
+            operations = FuseOperations(key, repository, manifest, archive)
+            self.print_verbose("Mounting filesystem")
+            try:
+                operations.mount(args.mountpoint, args.options, args.foreground)
+            except RuntimeError:
+                # Relevant error message already printed to stderr by fuse
+                self.exit_code = EXIT_ERROR
+        finally:
+            repository.close()
         return self.exit_code
 
     def do_list(self, args):

borg/locking.py

@@ -2,7 +2,6 @@ import errno
 import json
 import os
 import socket
-import threading
 import time
 
 from borg.helpers import Error
@@ -10,13 +9,17 @@ from borg.helpers import Error
 ADD, REMOVE = 'add', 'remove'
 SHARED, EXCLUSIVE = 'shared', 'exclusive'
 
+# only determine the PID and hostname once.
+# for FUSE mounts, we fork a child process that needs to release
+# the lock made by the parent, so it needs to use the same PID for that.
+_pid = os.getpid()
+_hostname = socket.gethostname()
+
 
 def get_id():
     """Get identification tuple for 'us'"""
-    hostname = socket.gethostname()
-    pid = os.getpid()
-    tid = threading.current_thread().ident & 0xffffffff
-    return hostname, pid, tid
+    thread_id = 0
+    return _hostname, _pid, thread_id
 
 
 class TimeoutTimer: