diff options
author | Paul Barker <pbarker@konsulko.com> | 2021-04-29 15:11:11 +0100 |
---|---|---|
committer | Richard Purdie <richard.purdie@linuxfoundation.org> | 2021-05-06 11:07:12 +0100 |
commit | 39c7c158c52157b18f5ccbbd673e3298e6402f52 (patch) | |
tree | db21f88cccb26f0df28a23ab50438fd043c48864 | |
parent | b3da56240c0f92efab1c0b293738c35c0f1ee6ab (diff) | |
download | bitbake-contrib-39c7c158c52157b18f5ccbbd673e3298e6402f52.tar.gz |
prserv: Extract daemonization from PRServer class
The code to start the prservice process as a daemon is extracted out of
the PRServer class and simplified. This makes the PRServer class easier
to modernise as it no longer needs to worry about process management.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
-rw-r--r-- | lib/prserv/serv.py | 175 |
1 files changed, 72 insertions, 103 deletions
diff --git a/lib/prserv/serv.py b/lib/prserv/serv.py index 5d6520da8..24a8c4bac 100644 --- a/lib/prserv/serv.py +++ b/lib/prserv/serv.py @@ -34,7 +34,7 @@ singleton = None class PRServer(SimpleXMLRPCServer): - def __init__(self, dbfile, logfile, interface, daemon=True): + def __init__(self, dbfile, logfile, interface): ''' constructor ''' try: SimpleXMLRPCServer.__init__(self, interface, @@ -47,7 +47,6 @@ class PRServer(SimpleXMLRPCServer): raise PRServiceConfigError self.dbfile=dbfile - self.daemon=daemon self.logfile=logfile self.working_thread=None self.host, self.port = self.socket.getsockname() @@ -176,106 +175,6 @@ class PRServer(SimpleXMLRPCServer): os.close(self.quitpipein) return - def start(self): - if self.daemon: - pid = self.daemonize() - else: - pid = self.fork() - self.pid = pid - - # Ensure both the parent sees this and the child from the work_forever log entry above - logger.info("Started PRServer with DBfile: %s, IP: %s, PORT: %s, PID: %s" % - (self.dbfile, self.host, self.port, str(pid))) - - def delpid(self): - os.remove(self.pidfile) - - def daemonize(self): - """ - See Advanced Programming in the UNIX, Sec 13.3 - """ - try: - pid = os.fork() - if pid > 0: - os.waitpid(pid, 0) - #parent return instead of exit to give control - return pid - except OSError as e: - raise Exception("%s [%d]" % (e.strerror, e.errno)) - - os.setsid() - """ - fork again to make sure the daemon is not session leader, - which prevents it from acquiring controlling terminal - """ - try: - pid = os.fork() - if pid > 0: #parent - os._exit(0) - except OSError as e: - raise Exception("%s [%d]" % (e.strerror, e.errno)) - - self.cleanup_handles() - os._exit(0) - - def fork(self): - try: - pid = os.fork() - if pid > 0: - self.socket.close() # avoid ResourceWarning in parent - return pid - except OSError as e: - raise Exception("%s [%d]" % (e.strerror, e.errno)) - - bb.utils.signal_on_parent_exit("SIGTERM") - self.cleanup_handles() - os._exit(0) - - def cleanup_handles(self): - os.chdir("/") - - sys.stdout.flush() - sys.stderr.flush() - - # We could be called from a python thread with io.StringIO as - # stdout/stderr or it could be 'real' unix fd forking where we need - # to physically close the fds to prevent the program launching us from - # potentially hanging on a pipe. Handle both cases. - si = open('/dev/null', 'r') - try: - os.dup2(si.fileno(),sys.stdin.fileno()) - except (AttributeError, io.UnsupportedOperation): - sys.stdin = si - so = open(self.logfile, 'a+') - try: - os.dup2(so.fileno(),sys.stdout.fileno()) - except (AttributeError, io.UnsupportedOperation): - sys.stdout = so - try: - os.dup2(so.fileno(),sys.stderr.fileno()) - except (AttributeError, io.UnsupportedOperation): - sys.stderr = so - - # Clear out all log handlers prior to the fork() to avoid calling - # event handlers not part of the PRserver - for logger_iter in logging.Logger.manager.loggerDict.keys(): - logging.getLogger(logger_iter).handlers = [] - - # Ensure logging makes it to the logfile - streamhandler = logging.StreamHandler() - streamhandler.setLevel(logging.DEBUG) - formatter = bb.msg.BBLogFormatter("%(levelname)s: %(message)s") - streamhandler.setFormatter(formatter) - logger.addHandler(streamhandler) - - # write pidfile - pid = str(os.getpid()) - with open(self.pidfile, 'w') as pf: - pf.write("%s\n" % pid) - - self.work_forever() - self.delpid() - class PRServSingleton(object): def __init__(self, dbfile, logfile, interface): self.dbfile = dbfile @@ -324,6 +223,76 @@ class PRServerConnection(object): def getinfo(self): return self.host, self.port +def run_as_daemon(func, pidfile, logfile): + """ + See Advanced Programming in the UNIX, Sec 13.3 + """ + try: + pid = os.fork() + if pid > 0: + os.waitpid(pid, 0) + #parent return instead of exit to give control + return pid + except OSError as e: + raise Exception("%s [%d]" % (e.strerror, e.errno)) + + os.setsid() + """ + fork again to make sure the daemon is not session leader, + which prevents it from acquiring controlling terminal + """ + try: + pid = os.fork() + if pid > 0: #parent + os._exit(0) + except OSError as e: + raise Exception("%s [%d]" % (e.strerror, e.errno)) + + os.chdir("/") + + sys.stdout.flush() + sys.stderr.flush() + + # We could be called from a python thread with io.StringIO as + # stdout/stderr or it could be 'real' unix fd forking where we need + # to physically close the fds to prevent the program launching us from + # potentially hanging on a pipe. Handle both cases. + si = open('/dev/null', 'r') + try: + os.dup2(si.fileno(),sys.stdin.fileno()) + except (AttributeError, io.UnsupportedOperation): + sys.stdin = si + so = open(logfile, 'a+') + try: + os.dup2(so.fileno(),sys.stdout.fileno()) + except (AttributeError, io.UnsupportedOperation): + sys.stdout = so + try: + os.dup2(so.fileno(),sys.stderr.fileno()) + except (AttributeError, io.UnsupportedOperation): + sys.stderr = so + + # Clear out all log handlers prior to the fork() to avoid calling + # event handlers not part of the PRserver + for logger_iter in logging.Logger.manager.loggerDict.keys(): + logging.getLogger(logger_iter).handlers = [] + + # Ensure logging makes it to the logfile + streamhandler = logging.StreamHandler() + streamhandler.setLevel(logging.DEBUG) + formatter = bb.msg.BBLogFormatter("%(levelname)s: %(message)s") + streamhandler.setFormatter(formatter) + logger.addHandler(streamhandler) + + # write pidfile + pid = str(os.getpid()) + with open(pidfile, 'w') as pf: + pf.write("%s\n" % pid) + + func() + os.remove(pidfile) + os._exit(0) + def start_daemon(dbfile, host, port, logfile): ip = socket.gethostbyname(host) pidfile = PIDPREFIX % (ip, port) @@ -339,7 +308,7 @@ def start_daemon(dbfile, host, port, logfile): return 1 server = PRServer(os.path.abspath(dbfile), os.path.abspath(logfile), (ip,port)) - server.start() + run_as_daemon(server.work_forever, pidfile, os.path.abspath(logfile)) # Sometimes, the port (i.e. localhost:0) indicated by the user does not match with # the one the server actually is listening, so at least warn the user about it |