OILS / opy / _regtest / src / atexit.py View on Github | oilshell.org

66 lines, 36 significant
1from __future__ import print_function # for OPy compiler
2"""
3atexit.py - allow programmer to define multiple exit functions to be executed
4upon normal program termination.
5
6One public function, register, is defined.
7"""
8
9__all__ = ["register"]
10
11import sys
12
13_exithandlers = []
14def _run_exitfuncs():
15 """run any registered exit functions
16
17 _exithandlers is traversed in reverse order so functions are executed
18 last in, first out.
19 """
20
21 exc_info = None
22 while _exithandlers:
23 func, targs, kargs = _exithandlers.pop()
24 try:
25 func(*targs, **kargs)
26 except SystemExit:
27 exc_info = sys.exc_info()
28 except:
29 import traceback
30 print("Error in atexit._run_exitfuncs:", file=sys.stderr)
31 traceback.print_exc()
32 exc_info = sys.exc_info()
33
34 if exc_info is not None:
35 raise exc_info[0], exc_info[1], exc_info[2]
36
37
38def register(func, *targs, **kargs):
39 """register a function to be executed upon normal program termination
40
41 func - function to be called at exit
42 targs - optional arguments to pass to func
43 kargs - optional keyword arguments to pass to func
44
45 func is returned to facilitate usage as a decorator.
46 """
47 _exithandlers.append((func, targs, kargs))
48 return func
49
50if hasattr(sys, "exitfunc"):
51 # Assume it's another registered exit function - append it to our list
52 register(sys.exitfunc)
53sys.exitfunc = _run_exitfuncs
54
55if __name__ == "__main__":
56 def x1():
57 print("running x1")
58 def x2(n):
59 print("running x2(%r)" % (n,))
60 def x3(n, kwd=None):
61 print("running x3(%r, kwd=%r)" % (n, kwd))
62
63 register(x1)
64 register(x2, 12)
65 register(x3, 5, "bar")
66 register(x3, "no kwd args")