##// END OF EJS Templates
worker: ignore meaningless exit status indication returned by os.waitpid()...
worker: ignore meaningless exit status indication returned by os.waitpid() Before this patch, worker implementation assumes that os.waitpid() with os.WNOHANG returns '(0, 0)' for still running child process. This is explicitly specified as below in Python API document. os.WNOHANG The option for waitpid() to return immediately if no child process status is available immediately. The function returns (0, 0) in this case. On the other hand, POSIX specification doesn't define the "stat_loc" value returned by waitpid() with WNOHANG for such child process. http://pubs.opengroup.org/onlinepubs/9699919799/functions/waitpid.html CPython implementation for os.waitpid() on POSIX doesn't take any care of this gap, and this may cause unexpected "exit status indication" even on POSIX conformance platform. For example, os.waitpid() with os.WNOHANG returns non-zero "exit status indication" on FreeBSD. This implies os.kill() with own pid or sys.exit() with non-zero exit code, even if no child process fails. To ignore meaningless exit status indication returned by os.waitpid(), this patch skips subsequent steps forcibly, if os.waitpid() returns 0 as pid. This patch also arranges examination of 'p' value for readability. FYI, there are some issues below about this behavior reported for CPython. https://bugs.python.org/issue21791 https://bugs.python.org/issue27808

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server.py
162 lines | 4.8 KiB | text/x-python | PythonLexer
# server.py - utility and factory of server
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import errno
import os
import sys
import tempfile
from .i18n import _
from . import (
chgserver,
commandserver,
error,
hgweb,
util,
)
def runservice(opts, parentfn=None, initfn=None, runfn=None, logfile=None,
runargs=None, appendpid=False):
'''Run a command as a service.'''
def writepid(pid):
if opts['pid_file']:
if appendpid:
mode = 'a'
else:
mode = 'w'
fp = open(opts['pid_file'], mode)
fp.write(str(pid) + '\n')
fp.close()
if opts['daemon'] and not opts['daemon_postexec']:
# Signal child process startup with file removal
lockfd, lockpath = tempfile.mkstemp(prefix='hg-service-')
os.close(lockfd)
try:
if not runargs:
runargs = util.hgcmd() + sys.argv[1:]
runargs.append('--daemon-postexec=unlink:%s' % lockpath)
# Don't pass --cwd to the child process, because we've already
# changed directory.
for i in xrange(1, len(runargs)):
if runargs[i].startswith('--cwd='):
del runargs[i]
break
elif runargs[i].startswith('--cwd'):
del runargs[i:i + 2]
break
def condfn():
return not os.path.exists(lockpath)
pid = util.rundetached(runargs, condfn)
if pid < 0:
raise error.Abort(_('child process failed to start'))
writepid(pid)
finally:
try:
os.unlink(lockpath)
except OSError as e:
if e.errno != errno.ENOENT:
raise
if parentfn:
return parentfn(pid)
else:
return
if initfn:
initfn()
if not opts['daemon']:
writepid(util.getpid())
if opts['daemon_postexec']:
try:
os.setsid()
except AttributeError:
pass
for inst in opts['daemon_postexec']:
if inst.startswith('unlink:'):
lockpath = inst[7:]
os.unlink(lockpath)
elif inst.startswith('chdir:'):
os.chdir(inst[6:])
elif inst != 'none':
raise error.Abort(_('invalid value for --daemon-postexec: %s')
% inst)
util.hidewindow()
util.stdout.flush()
util.stderr.flush()
nullfd = os.open(os.devnull, os.O_RDWR)
logfilefd = nullfd
if logfile:
logfilefd = os.open(logfile, os.O_RDWR | os.O_CREAT | os.O_APPEND)
os.dup2(nullfd, 0)
os.dup2(logfilefd, 1)
os.dup2(logfilefd, 2)
if nullfd not in (0, 1, 2):
os.close(nullfd)
if logfile and logfilefd not in (0, 1, 2):
os.close(logfilefd)
if runfn:
return runfn()
_cmdservicemap = {
'chgunix': chgserver.chgunixservice,
'pipe': commandserver.pipeservice,
'unix': commandserver.unixforkingservice,
}
def _createcmdservice(ui, repo, opts):
mode = opts['cmdserver']
try:
return _cmdservicemap[mode](ui, repo, opts)
except KeyError:
raise error.Abort(_('unknown mode %s') % mode)
def _createhgwebservice(ui, repo, opts):
# this way we can check if something was given in the command-line
if opts.get('port'):
opts['port'] = util.getport(opts.get('port'))
alluis = set([ui])
if repo:
baseui = repo.baseui
alluis.update([repo.baseui, repo.ui])
else:
baseui = ui
webconf = opts.get('web_conf') or opts.get('webdir_conf')
if webconf:
# load server settings (e.g. web.port) to "copied" ui, which allows
# hgwebdir to reload webconf cleanly
servui = ui.copy()
servui.readconfig(webconf, sections=['web'])
alluis.add(servui)
else:
servui = ui
optlist = ("name templates style address port prefix ipv6"
" accesslog errorlog certificate encoding")
for o in optlist.split():
val = opts.get(o, '')
if val in (None, ''): # should check against default options instead
continue
for u in alluis:
u.setconfig("web", o, val, 'serve')
app = hgweb.createapp(baseui, repo, webconf)
return hgweb.httpservice(servui, app, opts)
def createservice(ui, repo, opts):
if opts["cmdserver"]:
return _createcmdservice(ui, repo, opts)
else:
return _createhgwebservice(ui, repo, opts)