bin/server.py

   1 #  -*- coding: iso-8859-1 -*-
   2 # Copyright (C) 2007-2023  CEA, EDF, OPEN CASCADE
   3 #
   4 # Copyright (C) 2003-2007  OPEN CASCADE, EADS/CCR, LIP6, CEA/DEN,
   5 # CEDRAT, EDF R&D, LEG, PRINCIPIA R&D, BUREAU VERITAS
   6 #
   7 # This library is free software; you can redistribute it and/or
   8 # modify it under the terms of the GNU Lesser General Public
   9 # License as published by the Free Software Foundation; either
  10 # version 2.1 of the License, or (at your option) any later version.
  11 #
  12 # This library is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 # Lesser General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU Lesser General Public
  18 # License along with this library; if not, write to the Free Software
  19 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 #
  21 # See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
  22 #
  23
  24 import os, sys, string
  25 from salome_utils import getHostName
  26 process_id = {}
  27 import logging
  28
  29 # -----------------------------------------------------------------------------
  30 #
  31 # Definition des classes d'objets pour le lancement des Server CORBA
  32 #
  33
  34 class Server:
  35     """Generic class for CORBA server launch"""
  36
  37     server_launch_mode = "daemon"
  38
  39     def initArgs(self):
  40         self.PID=None
  41         self.CMD=[]
  42         self.ARGS=[]
  43         if self.args.get('xterm'):
  44           if sys.platform != "win32":
  45             self.ARGS=['xterm', '-iconic', '-sb', '-sl', '500', '-hold']
  46           else:
  47             self.ARGS=['cmd', '/c', 'start  cmd.exe', '/K']
  48
  49     def __init__(self,args):
  50         self.args=args
  51         self.initArgs()
  52
  53     @staticmethod
  54     def set_server_launch_mode(mode):
  55       if mode == "daemon" or mode == "fork":
  56         Server.server_launch_mode = mode
  57       else:
  58         raise Exception("Unsupported server launch mode: %s" % mode)
  59
  60     def run(self, daemon=False):
  61         global process_id
  62         myargs=self.ARGS
  63         if self.args.get('xterm'):
  64             # (Debian) send LD_LIBRARY_PATH to children shells (xterm)
  65           if sys.platform == "darwin":
  66               env_ld_library_path=['env', 'DYLD_LIBRARY_PATH='
  67                                    + os.getenv("DYLD_FALLBACK_LIBRARY_PATH")]
  68               myargs = myargs +['-T']+self.CMD[:1]+['-e'] + env_ld_library_path
  69           elif sys.platform != "win32":
  70               env_ld_library_path=['env', 'LD_LIBRARY_PATH='
  71                                    + os.getenv("LD_LIBRARY_PATH")]
  72               myargs = myargs +['-T']+self.CMD[:1]+['-e'] + env_ld_library_path
  73         command = myargs + self.CMD
  74         for sapcfg in ["SalomeAppSLConfig","SalomeAppConfig"]:
  75           if sapcfg in os.environ:
  76             logging.getLogger().debug("{}={}".format(sapcfg,os.environ[sapcfg]))
  77         command1 = (" ".join(command)).replace("(","\\\(") ; command1 = command1.replace(")","\\\)")
  78         logging.getLogger().debug("Command to be launched : {}".format(command1))
  79         # print("command = ", command)
  80         if sys.platform == "win32":
  81           import subprocess
  82           if daemon:
  83             DETACHED_PROCESS = 0x00000008
  84             pid = subprocess.Popen(command, creationflags=DETACHED_PROCESS).pid
  85           else:
  86             pid = subprocess.Popen(command).pid
  87         elif Server.server_launch_mode == "fork":
  88           pid = os.spawnvp(os.P_NOWAIT, command[0], command)
  89         else: # Server launch mode is daemon
  90           pid=self.daemonize(command)
  91         if pid is not None:
  92           #store process pid if it really exists
  93           process_id[pid]=self.CMD
  94         self.PID = pid
  95         logging.getLogger().debug("PID of launched command : {}".format(pid))
  96         return pid
  97
  98     def daemonize(self,args):
  99         # to daemonize a process need to do the UNIX double-fork magic
 100         # see Stevens, "Advanced Programming in the UNIX Environment" for details (ISBN 0201563177)
 101         # and UNIX Programming FAQ 1.7 How do I get my program to act like a daemon?
 102         #     http://www.erlenstar.demon.co.uk/unix/faq_2.html#SEC16
 103         #open a pipe
 104         c2pread, c2pwrite = os.pipe()
 105         #do first fork
 106         pid=os.fork()
 107         if pid > 0:
 108           #first parent
 109           os.close(c2pwrite)
 110           #receive real pid from child
 111           data=os.read(c2pread,24) #read 24 bytes
 112           os.waitpid(pid,0) #remove zombie
 113           os.close(c2pread)
 114           # return : first parent
 115           childpid=int(data)
 116           if childpid==-1:
 117             return None
 118           try:
 119             os.kill(childpid,0)
 120             return childpid
 121           except Exception:
 122             return None
 123
 124         #first child
 125         # decouple from parent environment
 126         os.setsid()
 127         os.close(c2pread)
 128
 129         # do second fork : second child not a session leader
 130         try:
 131           pid = os.fork()
 132           if pid > 0:
 133             #send real pid to parent
 134             pid_str = "%d" % pid
 135             os.write(c2pwrite,pid_str.encode())
 136             os.close(c2pwrite)
 137             # exit from second parent
 138             os._exit(0)
 139         except OSError as e:
 140           print("fork #2 failed: %d (%s)" % (e.errno, e.strerror), file=sys.stderr)
 141           os.write(c2pwrite,"-1")
 142           os.close(c2pwrite)
 143           sys.exit(1)
 144
 145         #I am a daemon
 146         os.close(0) #close stdin
 147         os.open("/dev/null", os.O_RDWR)  # redirect standard input (0) to /dev/null
 148         try:
 149           os.execvp(args[0], args)
 150         except OSError as e:
 151           print("(%s) launch failed: %d (%s)" % (args[0],e.errno, e.strerror), file=sys.stderr)
 152           os._exit(127)