bitbake: Automatically start local PR service.

[YOCTO #1126]
A local PR service will be started and stopped automatically along
with the bitbake invocation/ternimation.

This local PR service will be started only and if only when the
PRSERV_HOST is set to 'localhost' and PRSERV_PORT is set to '0'.

When started, the sqlite3 database is stored at
"${PERSISTEN_DIR}/prserv.sqlite3" or "${CACHE}/prserv.sqlite3".

(Bitbake rev: 9d8f45407c67ed0d3c4f820cf646de3c385067c7)

Signed-off-by: Lianhao Lu <lianhao.lu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/cooker.py

@@ -36,6 +36,7 @@ from functools import wraps
 from collections import defaultdict
 import bb, bb.exceptions, bb.command
 from bb import utils, data, parse, event, cache, providers, taskdata, runqueue
+import prserv.serv
 
 logger      = logging.getLogger("BitBake")
 collectlog  = logging.getLogger("BitBake.Collection")
@@ -1311,9 +1312,11 @@ class BBCooker:
         # Empty the environment. The environment will be populated as
         # necessary from the data store.
         #bb.utils.empty_environment()
+        prserv.serv.auto_start(self.configuration.data)
         return
 
     def post_serve(self):
+        prserv.serv.auto_shutdown(self.configuration.data)
         bb.event.fire(CookerExit(), self.configuration.event_data)
 
     def shutdown(self):