1#!/usr/bin/python 2 3import common 4import sys, os, signal, time, subprocess, fcntl 5 6logdir = sys.argv[1] 7stdout_start = int(sys.argv[2]) # number of bytes we can skip on stdout 8stderr_start = int(sys.argv[3]) # nubmer of bytes we can skip on stderr 9# TODO (crosbug.com/38224)- sbasi: Remove extra logging. 10stderr = open(os.path.join(logdir, 'stderr'), 'a', 0) 11 12print >> stderr, 'Entered autotestd_monitor.' 13# if any of our tail processes die, the monitor should die too 14def kill_self(signum, frame): 15 os.kill(os.getpid(), signal.SIGTERM) 16signal.signal(signal.SIGCHLD, kill_self) 17 18devnull = open(os.devnull, 'w') 19 20# launch some tail processes to pump the std* streams 21def launch_tail(filename, outstream, start): 22 path = os.path.join(logdir, filename) 23 argv = ['tail', '--retry', '--follow=name', '--bytes=+%d' % start, path] 24 # stdout=sys.stdout fails on pre-2.5 python (bug in subprocess module) 25 if outstream != subprocess.PIPE and outstream.fileno() == 1: 26 return subprocess.Popen(argv, stderr=devnull) 27 else: 28 return subprocess.Popen(argv, stdout=outstream, stderr=devnull) 29stdout_pump = launch_tail('stdout', sys.stdout, stdout_start) 30stderr_pump = launch_tail('stderr', sys.stderr, stderr_start) 31 32print >> stderr, 'Finished launching tail subprocesses.' 33 34# wait for logdir/started to exist to be sure autotestd is started 35start_time = time.time() 36started_file_path = os.path.join(logdir, 'started') 37while not os.path.exists(started_file_path): 38 time.sleep(1) 39 if time.time() - start_time >= 30: 40 raise Exception("autotestd failed to start in %s" % logdir) 41 42print >> stderr, 'Finished waiting on autotestd to start.' 43 44# watch the exit code file for an exit 45exit_code_file = open(os.path.join(logdir, 'exit_code')) 46fcntl.flock(exit_code_file, fcntl.LOCK_EX) 47print >> stderr, 'Got lock of exit_code_file.' 48try: 49 exit_code = exit_code_file.read() 50 if len(exit_code) != 4: 51 exit_code = -signal.SIGKILL # autotestd was nuked 52 else: 53 exit_code = int(exit_code) 54finally: 55 fcntl.flock(exit_code_file, fcntl.LOCK_UN) 56 exit_code_file.close() 57 print >> stderr, 'Released lock of exit_code_file and closed it.' 58 59# tail runs in 1s polling loop, so give them a chance to finish 60time.sleep(2) 61 62print >> stderr, 'Killing child processes.' 63# clear the SIGCHLD handler so that killing the tails doesn't kill us 64signal.signal(signal.SIGCHLD, signal.SIG_DFL) 65os.kill(stdout_pump.pid, signal.SIGTERM) 66os.kill(stderr_pump.pid, signal.SIGTERM) 67 68# exit (with the same code as autotestd) 69sys.exit(exit_code) 70