EmbeddedPkg: Extend NvVarStoreFormattedLib LIBRARY_CLASS

[mirror_edk2.git] / AppPkg / Applications / Python / Python-2.7.2 / Lib / test / test_threaded_import.py

# This is a variant of the very old (early 90's) file\r
# Demo/threads/bug.py.  It simply provokes a number of threads into\r
# trying to import the same module "at the same time".\r
# There are no pleasant failure modes -- most likely is that Python\r
# complains several times about module random having no attribute\r
# randrange, and then Python hangs.\r
\r
import unittest\r
from test.test_support import verbose, TestFailed, import_module\r
thread = import_module('thread')\r
\r
critical_section = thread.allocate_lock()\r
done = thread.allocate_lock()\r
\r
def task():\r
    global N, critical_section, done\r
    import random\r
    x = random.randrange(1, 3)\r
    critical_section.acquire()\r
    N -= 1\r
    # Must release critical_section before releasing done, else the main\r
    # thread can exit and set critical_section to None as part of global\r
    # teardown; then critical_section.release() raises AttributeError.\r
    finished = N == 0\r
    critical_section.release()\r
    if finished:\r
        done.release()\r
\r
def test_import_hangers():\r
    import sys\r
    if verbose:\r
        print "testing import hangers ...",\r
\r
    import test.threaded_import_hangers\r
    try:\r
        if test.threaded_import_hangers.errors:\r
            raise TestFailed(test.threaded_import_hangers.errors)\r
        elif verbose:\r
            print "OK."\r
    finally:\r
        # In case this test is run again, make sure the helper module\r
        # gets loaded from scratch again.\r
        del sys.modules['test.threaded_import_hangers']\r
\r
# Tricky:  When regrtest imports this module, the thread running regrtest\r
# grabs the import lock and won't let go of it until this module returns.\r
# All other threads attempting an import hang for the duration.  Since\r
# this test spawns threads that do little *but* import, we can't do that\r
# successfully until after this module finishes importing and regrtest\r
# regains control.  To make this work, a special case was added to\r
# regrtest to invoke a module's "test_main" function (if any) after\r
# importing it.\r
\r
def test_main():        # magic name!  see above\r
    global N, done\r
\r
    import imp\r
    if imp.lock_held():\r
        # This triggers on, e.g., from test import autotest.\r
        raise unittest.SkipTest("can't run when import lock is held")\r
\r
    done.acquire()\r
    for N in (20, 50) * 3:\r
        if verbose:\r
            print "Trying", N, "threads ...",\r
        for i in range(N):\r
            thread.start_new_thread(task, ())\r
        done.acquire()\r
        if verbose:\r
            print "OK."\r
    done.release()\r
\r
    test_import_hangers()\r
\r
if __name__ == "__main__":\r
    test_main()\r