1 # server.py - utility and factory of server

     2 #

     3 # Copyright 2005-2007 Matt Mackall <mpm@selenic.com>

     4 #

     5 # This software may be used and distributed according to the terms of the

     6 # GNU General Public License version 2 or any later version.

     7 

     8 from __future__ import absolute_import

     9 

    10 import errno

    11 import os

    12 import sys

    13 import tempfile

    14 

    15 from .i18n import _

    16 

    17 from . import (

    18     error,

    19     util,

    20 )

    21 

    22 def runservice(opts, parentfn=None, initfn=None, runfn=None, logfile=None,

    23                runargs=None, appendpid=False):

    24     '''Run a command as a service.'''

    25 

    26     def writepid(pid):

    27         if opts['pid_file']:

    28             if appendpid:

    29                 mode = 'a'

    30             else:

    31                 mode = 'w'

    32             fp = open(opts['pid_file'], mode)

    33             fp.write(str(pid) + '\n')

    34             fp.close()

    35 

    36     if opts['daemon'] and not opts['daemon_postexec']:

    37         # Signal child process startup with file removal

    38         lockfd, lockpath = tempfile.mkstemp(prefix='hg-service-')

    39         os.close(lockfd)

    40         try:

    41             if not runargs:

    42                 runargs = util.hgcmd() + sys.argv[1:]

    43             runargs.append('--daemon-postexec=unlink:%s' % lockpath)

    44             # Don't pass --cwd to the child process, because we've already

    45             # changed directory.

    46             for i in xrange(1, len(runargs)):

    47                 if runargs[i].startswith('--cwd='):

    48                     del runargs[i]

    49                     break

    50                 elif runargs[i].startswith('--cwd'):

    51                     del runargs[i:i + 2]

    52                     break

    53             def condfn():

    54                 return not os.path.exists(lockpath)

    55             pid = util.rundetached(runargs, condfn)

    56             if pid < 0:

    57                 raise error.Abort(_('child process failed to start'))

    58             writepid(pid)

    59         finally:

    60             try:

    61                 os.unlink(lockpath)

    62             except OSError as e:

    63                 if e.errno != errno.ENOENT:

    64                     raise

    65         if parentfn:

    66             return parentfn(pid)

    67         else:

    68             return

    69 

    70     if initfn:

    71         initfn()

    72 

    73     if not opts['daemon']:

    74         writepid(util.getpid())

    75 

    76     if opts['daemon_postexec']:

    77         try:

    78             os.setsid()

    79         except AttributeError:

    80             pass

    81         for inst in opts['daemon_postexec']:

    82             if inst.startswith('unlink:'):

    83                 lockpath = inst[7:]

    84                 os.unlink(lockpath)

    85             elif inst.startswith('chdir:'):

    86                 os.chdir(inst[6:])

    87             elif inst != 'none':

    88                 raise error.Abort(_('invalid value for --daemon-postexec: %s')

    89                                   % inst)

    90         util.hidewindow()

    91         util.stdout.flush()

    92         util.stderr.flush()

    93 

    94         nullfd = os.open(os.devnull, os.O_RDWR)

    95         logfilefd = nullfd

    96         if logfile:

    97             logfilefd = os.open(logfile, os.O_RDWR | os.O_CREAT | os.O_APPEND)

    98         os.dup2(nullfd, 0)

    99         os.dup2(logfilefd, 1)

   100         os.dup2(logfilefd, 2)

   101         if nullfd not in (0, 1, 2):

   102             os.close(nullfd)

   103         if logfile and logfilefd not in (0, 1, 2):

   104             os.close(logfilefd)

   105 

   106     if runfn:

   107         return runfn()