pymin/procman.py

   1 # vim: set encoding=utf-8 et sw=4 sts=4 :
   2
   3 import os
   4 import errno
   5 import subprocess
   6
   7 class ProcessInfo:
   8     def __init__(self, name, process, args, kw, callback=None, persist=False):
   9         self.name = name
  10         self.process = process
  11         self.args = args
  12         self.kw = kw
  13         self.callback = callback
  14         self.persist = persist
  15     def __repr__(self):
  16         return 'ProcessInfo(name=%s, pid=%s, persist=%s, cb=%s, args=%s)' % (
  17                     self.name, self.process.pid, self.persist,
  18                     self.callback.__name__, self.args)
  19
  20 class ProcessManager:
  21
  22     def __init__(self):
  23         self.namemap = dict()
  24         self.pidmap = dict()
  25
  26     def call(self, name, callback, persist, *args, **kw):
  27         proc = subprocess.Popen(*args, **kw)
  28         procinfo = ProcessInfo(name, proc, args, kw, callback, persist)
  29         self.namemap[name] = self.pidmap[proc.pid] = procinfo
  30
  31     def sigchild_handler(self, signum):
  32         try:
  33             (pid, status) = os.waitpid(-1, os.WNOHANG)
  34         except OSError, e:
  35             if e.errno is e.ECHILD:
  36                 return
  37             raise
  38         while pid:
  39             if pid in self.pidmap:
  40                 p = self.pidmap[pid]
  41                 del self.namemap[p.name]
  42                 del self.pidmap[pid]
  43                 if p.callback is not None:
  44                     p.callback(p)
  45                 if p.persist:
  46                     self.call(p.name, p.callback, True, *p.args, **p.kw)
  47             try:
  48                 (pid, status) = os.waitpid(-1, os.WNOHANG)
  49             except OSError, e:
  50                 if e.errno == errno.ECHILD:
  51                     return
  52                 raise
  53
  54     def __getitem__(self, name):
  55         if isinstance(name, basestring): # is a name
  56             return self.namemap[name]
  57         else: # is a pid
  58             return self.pidmap[name]
  59
  60     def __contains__(self, name):
  61         if isinstance(name, basestring): # is a name
  62             return name in self.namemap
  63         else: # is a pid
  64             return name in self.pidmap
  65
  66
  67 if __name__ == '__main__':
  68
  69     import signal
  70     import time
  71
  72     sig = None
  73
  74     def sigchild_handler(signum, stacktrace):
  75         global sig
  76         sig = signum
  77         print 'SIGCHLD', signum
  78
  79     def test_notify(proc):
  80         print 'test died:', proc, proc.name, proc.process.pid
  81
  82     procman = ProcessManager()
  83
  84     signal.signal(signal.SIGCHLD, sigchild_handler)
  85
  86     procman.call('test', test_notify, True, ('sleep', '5'))
  87
  88     while True:
  89         time.sleep(1)
  90         print "Esperando...",
  91         if 'test' in procman:
  92             print procman['test']
  93         else:
  94             print
  95         if sig == signal.SIGCHLD:
  96             sig = None
  97             procman.sigchild_handler(sig)
  98