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# vi: ts=4 expandtab
#
# Copyright (C) 2011 Canonical Ltd.
#
# Author: Scott Moser <scott.moser@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from cloudinit.settings import PER_INSTANCE
from cloudinit import util
import errno
import os
import subprocess
import sys
import time
frequency = PER_INSTANCE
def handle(_name, cfg, cloud, log, _args):
finalcmds = cfg.get("finalcmd")
if not finalcmds:
log.debug("No final commands")
return
mypid = os.getpid()
cmdline = util.load_file("/proc/%s/cmdline")
if not cmdline:
log.warn("Failed to get cmdline of current process")
return
try:
timeout = float(cfg.get("finalcmd_timeout", 30.0))
except ValueError:
log.warn("failed to convert finalcmd_timeout '%s' to float" %
cfg.get("finalcmd_timeout", 30.0))
return
devnull_fp = open("/dev/null", "w")
shellcode = util.shellify(finalcmds)
# note, after the fork, we do not use any of cloud-init's functions
# that would attempt to log. The primary reason for that is
# to allow the 'finalcmd' the ability to do just about anything
# and not depend on syslog services.
# Basically, it should "just work" to have finalcmd of:
# - sleep 30
# - /sbin/poweroff
finalcmd_d = os.path.join(cloud.get_ipath_cur(), "finalcmds")
util.fork_cb(run_after_pid_gone, mypid, cmdline, timeout,
runfinal, (shellcode, finalcmd_d, devnull_fp))
def execmd(exe_args, data_in=None, output=None):
try:
proc = subprocess.Popen(exe_args, stdin=subprocess.PIPE,
stdout=output, stderr=subprocess.STDOUT)
proc.communicate(data_in)
except Exception:
return 254
return proc.returncode()
def runfinal(shellcode, finalcmd_d, output=None):
ret = execmd(["/bin/sh"], data_in=shellcode, output=output)
if not (finalcmd_d and os.path.isdir(finalcmd_d)):
sys.exit(ret)
fails = 0
if ret != 0:
fails = 1
# now runparts the final command dir
for exe_name in sorted(os.listdir(finalcmd_d)):
exe_path = os.path.join(finalcmd_d, exe_name)
if os.path.isfile(exe_path) and os.access(exe_path, os.X_OK):
ret = execmd([exe_path], data_in=None, output=output)
if ret != 0:
fails += 1
sys.exit(fails)
def run_after_pid_gone(pid, pidcmdline, timeout, func, args):
# wait until pid, with /proc/pid/cmdline contents of pidcmdline
# is no longer alive. After it is gone, or timeout has passed
# execute func(args)
msg = "ERROR: Uncaught error"
end_time = time.time() + timeout
cmdline_f = "/proc/%s/cmdline" % pid
while True:
if time.time() > end_time:
msg = "timeout reached before %s ended" % pid
break
try:
cmdline = ""
with open(cmdline_f) as fp:
cmdline = fp.read()
if cmdline != pidcmdline:
msg = "cmdline changed for %s [now: %s]" % (pid, cmdline)
break
except IOError as ioerr:
if ioerr.errno == errno.ENOENT:
msg = "pidfile '%s' gone" % cmdline_f
else:
msg = "ERROR: IOError: %s" % ioerr
raise
break
except Exception as e:
msg = "ERROR: Exception: %s" % e
raise
if msg.startswith("ERROR:"):
sys.stderr.write(msg)
sys.stderr.write("Not executing finalcmd")
sys.exit(1)
sys.stderr.write("calling %s with %s\n" % (func, args))
sys.exit(func(*args))
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