Add tools so can close a dbus service after use.

Service will keep the dbus stream open for the life of the application,
this can ause issues on long running daemons. This adds a stop method and
a with processor so that the service can be stopped after use:

service = Service(...)
service.stop()

or

with Service(...) as service:
    -- use the service

adbus/__version__.py

@@ -1,3 +1,3 @@
 # == Copyright: 2017-2021, CCX Technologies
 
-__version__ = "1.1.6"
+__version__ = "1.2.0"

adbus/sdbus/service.pxi

@@ -1,13 +1,15 @@
-# Copyright: 2017, CCX Technologies
+# Copyright: 2017-2021, CCX Technologies
 #cython: language_level=3
 
 cdef class Service:
     cdef sdbus_h.sd_bus *bus
     cdef bytes name
     cdef bytes unique_name
     cdef bool connected
+    cdef bool process_loop
     cdef stdint.uint64_t flags
     cdef object loop
+    cdef object startup_task
 
     def __cinit__(self, name=None, loop=None, bus='system',
             replace_existing=False, allow_replacement=False, queue=False):
@@ -56,11 +58,27 @@ cdef class Service:
         if not loop:
             loop = get_event_loop()
 
-        loop.create_task(self.startup_process())
+        self.process_loop = True
+        self.startup_task = loop.create_task(self.startup_process())
         loop.add_reader(bus_fd, self.process)
 
         self.loop = loop
 
+    def stop(self):
+        self.startup_task.cancel()
+        bus_fd = sdbus_h.sd_bus_get_fd(self.bus)
+        if bus_fd > 0:
+            self.loop.remove_reader(bus_fd)
+        self.process_loop = False
+
+        self.bus = sdbus_h.sd_bus_flush_close_unref(self.bus)
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exception_type, exception_value, exception_traceback):
+        self.stop()
+
     def is_running(self):
         """Service is running."""
         return self.loop.is_running()
@@ -69,9 +87,6 @@ cdef class Service:
         """Get the service's asyncio loop."""
         return self.loop
 
-    def __dealloc__(self):
-        self.bus = sdbus_h.sd_bus_unref(self.bus)
-
     async def startup_process(self):
         self.process()
 
@@ -88,7 +103,7 @@ cdef class Service:
 
         self.connected = True
         try:
-            while True:
+            while self.process_loop:
                 r = sdbus_h.sd_bus_process(self.bus, NULL)
 
                 if r < 0:

adbus/sdbus_h.pxd

@@ -123,7 +123,7 @@ cdef extern from "systemd/sd-bus.h":
     int sd_bus_open_system(sd_bus **ret)
     int sd_bus_request_name(sd_bus *bus, const char *name, stdint.uint64_t flags)
     int sd_bus_get_unique_name(sd_bus *bus, const char **unique)
-    sd_bus *sd_bus_unref(sd_bus *bus)
+    sd_bus *sd_bus_flush_close_unref(sd_bus *bus)
 
     int sd_bus_add_object_vtable(sd_bus *bus, sd_bus_slot **slot,
             const char *path, const char *interface,

adbus/service.py

@@ -47,3 +47,12 @@ def is_running(self):
 
     def get_loop(self):
         return self.sdbus.get_loop()
+
+    def stop(self):
+        self.sdbus.stop()
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exception_type, exception_value, exception_traceback):
+        self.stop()