Source.Python forums

loading_state = itertools.cycle(['   ', '.  ', '.. ', '...'])
def build_loading_menu(menu, index):
    menu.clear()
    menu.append('Loading' + next(loading_state))
loading_menu = SimpleMenu(build_callback=build_loading_menu)


def _send_threaded_menu(index, callback, args, kwargs, set_page):
    print('DEBUG 1')

    # Returns a menu class which is ready to be sent to a player
    menu = callback(*args, **kwargs)

    print('DEBUG 2')

    # New menu has been loaded - We can close the old loading menu
    loading_menu.close(index)

    print('DEBUG 3')

    # Send new menu
    menu.send(index)

    print('DEBUG 4')

    # If set_page is defined - Set player page on new menu
    if set_page:
        print('DEBUG 5')

        menu.set_player_page(index, set_page)

    print('DEBUG 6')


def send_threaded_menu(index, callback, args=(), kwargs=None, set_page=None):
    kwargs = kwargs if kwargs is not None else dict()

    # Send loading menu
    loading_menu.send(index)

    # Add function to WorkerThread
    ThreadedClass.function_call(_send_threaded_menu, (index, callback, args, kwargs, set_page))

loading_state = itertools.cycle(['   ', '.  ', '.. ', '...'])
def build_loading_menu(menu, index):
    menu.clear()
    menu.append('Loading' + next(loading_state))
loading_menu = SimpleMenu(build_callback=build_loading_menu)


def _send_threaded_menu(index, callback, args, kwargs, set_page):
    print('DEBUG 1')

    # Returns a menu class which is ready to be sent to a player
    menu = callback(*args, **kwargs)

    print('DEBUG 2')

    # New menu has been loaded - We can close the old loading menu
    # loading_menu.close(index)

    print('DEBUG 3')

    # Send new menu
    menu.send(index)

    print('DEBUG 4')

    # If set_page is defined - Set player page on new menu
    if set_page:
        print('DEBUG 5')

        menu.set_player_page(index, set_page)

    print('DEBUG 6')


def send_threaded_menu(index, callback, args=(), kwargs=None, set_page=None):
    kwargs = kwargs if kwargs is not None else dict()

    # Send loading menu
    # loading_menu.send(index)

    # Add function to WorkerThread
    ThreadedClass.function_call(_send_threaded_menu, (index, callback, args, kwargs, set_page))

# Only an empty CS:S server is required for this test/explanation plugin.
# No bots; no players. Just load this test plugin with test1 uncommented.
# Then comment out test1, uncomment test2 and reload. Continue like that with test3.

from engines.server import engine_server
from memory import get_virtual_function
from memory import make_object
from bitbuffers import BitBufferWrite
from filters.recipients import RecipientFilter

# Import this snippet: https: //pastebin.com/raw/wbHxTt6d
from test6.worker import WorkerThread

# virtual bf_write	*UserMessageBegin( IRecipientFilter *filter, int msg_type ) = 0;
UserMessageBegin = get_virtual_function(engine_server, 'UserMessageBegin')

# virtual void		MessageEnd( void ) = 0;
MessageEnd = get_virtual_function(engine_server, 'MessageEnd')

recipients = RecipientFilter()

def test1(arg):
    print(arg, 'START')
    # Simply send a user message
    buffer = make_object(
        BitBufferWrite,
        UserMessageBegin(engine_server, recipients, 0))

    buffer.write_byte(0) # Required for user message 0

    # This will cause the thread do be busy and might cause a context switch.
    # Alternativly, time.sleep()
    y = 0
    for x in range(100000):
        y += x % 2

    MessageEnd(engine_server)

    print(arg, 'END')

def test2():
    buffer = UserMessageBegin(engine_server, recipients, 0)

    # Crashes here, because a second user message is started before the first
    # one is finished
    buffer = UserMessageBegin(engine_server, recipients, 0)

def test3():
    worker1 = WorkerThread()
    worker2 = WorkerThread()

    for x in range(10):
        worker1.add_job(test1, ['worker1'])
        worker2.add_job(test1, ['worker2'])

    # There is a very high chance that you crash. Even with only one worker
    # thread, because the main thread also continously starts user messages.
    # Context switching causes the function calls to test1() to stop somewhere
    # during the execution. It can be before line 1, in line 1, after line 1,
    # but before line 2. Basically, anywhere in that function, because it's not
    # atomic/thread safe.
    worker1.start()
    worker2.start()


# TEST 1 - Demonstrate a working user message. You server won't crash and the
# plugin will load fine.
#test1('main thread')

# TEST 2 - Demonstrate two calls to UserMessageBegin without finishing the
# first one. This will crash your server.
#test2()

# TEST 3 - Demonstrate a high chance of crashing. You might need to reload the
# plugin multiple times if you are lucky.
#test3()