#!/usr/bin/python3
#
# Collect information about processes which are still running after sending
# SIGTERM to them (which happens during computer shutdown in
# /etc/init.d/sendsigs in Debian/Ubuntu)
#
# Copyright (c) 2010 Canonical Ltd.
# Author: Martin Pitt <[email protected]>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version. See http://www.gnu.org/copyleft/gpl.html for
# the full text of the license.

import os, os.path, sys, errno, optparse

import apport, apport.fileutils, apport.hookutils


def parse_argv():
'''Parse command line and return (options, args).'''

optparser = optparse.OptionParser('%prog [options]')
optparser.add_option('-o', '--omit', metavar='PID', action='append',
default=[], dest='blacklist',
help='Ignore a particular process ID (can be specified multiple times)')

(opts, args) = optparser.parse_args()

if len(args) != 0:
optparser.error('This program does not take any non-option arguments. Please see --help.')
sys.exit(1)

return (opts, args)


def orphaned_processes(blacklist):
'''Yield an iterator of running process IDs.

This excludes PIDs which do not have a valid /proc/pid/exe symlink (e. g.
kernel processes), the PID of our own process, and everything that is
contained in the blacklist argument.
'''
my_pid = os.getpid()
my_sid = os.getsid(0)
for d in os.listdir('/proc'):
try:
pid = int(d)
except ValueError:
continue
if pid == 1 or pid == my_pid or d in blacklist:
apport.warning('ignoring: %s', d)
continue

try:
sid = os.getsid(pid)
except OSError:
# os.getsid() can fail with "No such process" if the process died
# in the meantime
continue

if sid == my_sid:
apport.warning('ignoring same sid: %s', d)
continue

try:
os.readlink(os.path.join('/proc', d, 'exe'))
except OSError as e:
if e.errno == errno.ENOENT:
# kernel thread or similar, silently ignore
continue
apport.warning('Could not read information about pid %s: %s', d, str(e))
continue

yield d


def do_report(pid, blacklist):
'''Create a report for a particular PID.'''

r = apport.Report('Bug')
try:
r.add_proc_info(pid)
except (ValueError, AssertionError):
# happens if ExecutablePath doesn't exist (any more?), ignore
return

r['Tags'] = 'shutdown-hang'
r['Title'] = 'does not terminate at computer shutdown'
if 'ExecutablePath' in r:
r['Title'] = os.path.basename(r['ExecutablePath']) + ' ' + r['Title']
r['Processes'] = apport.hookutils.command_output(['ps', 'aux'])
r['InitctlList'] = apport.hookutils.command_output(['initctl', 'list'])
if blacklist:
r['OmitPids'] = ' '.join(blacklist)

with open(apport.fileutils.make_report_path(r), 'wb') as f:
r.write(f)

#
# main
#

(opts, args) = parse_argv()

for p in orphaned_processes(opts.blacklist):
do_report(p, opts.blacklist)