# Very rudimentary test of thread module

# Create a bunch of threads, let each do some work, wait until all are done

from test.test_support import verbose

import random

import thread

import time

mutex = thread.allocate_lock()

rmutex = thread.allocate_lock() # for calls to random

running = 0

done = thread.allocate_lock()

done.acquire()

numtasks = 10

def task(ident):

    global running

    rmutex.acquire()

    delay = random.random() * numtasks

    rmutex.release()

    if verbose:

        print 'task', ident, 'will run for', round(delay, 1), 'sec'

    time.sleep(delay)

    if verbose:

        print 'task', ident, 'done'

    mutex.acquire()

    running = running - 1

    if running == 0:

        done.release()

    mutex.release()

next_ident = 0

def newtask():

    global next_ident, running

    mutex.acquire()

    next_ident = next_ident + 1

    if verbose:

        print 'creating task', next_ident

    thread.start_new_thread(task, (next_ident,))

    running = running + 1

    mutex.release()

for i in range(numtasks):

    newtask()

print 'waiting for all tasks to complete'

done.acquire()

print 'all tasks done'

class barrier:

    def __init__(self, n):

        self.n = n

        self.waiting = 0

        self.checkin  = thread.allocate_lock()

        self.checkout = thread.allocate_lock()

        self.checkout.acquire()

    def enter(self):

        checkin, checkout = self.checkin, self.checkout

        checkin.acquire()

        self.waiting = self.waiting + 1

        if self.waiting == self.n:

            self.waiting = self.n - 1

            checkout.release()

            return

        checkin.release()

        checkout.acquire()

        self.waiting = self.waiting - 1

        if self.waiting == 0:

            checkin.release()

            return

        checkout.release()

numtrips = 3

def task2(ident):

    global running

    for i in range(numtrips):

        if ident == 0:

            # give it a good chance to enter the next

            # barrier before the others are all out

            # of the current one

            delay = 0.001

        else:

            rmutex.acquire()

            delay = random.random() * numtasks

            rmutex.release()

        if verbose:

            print 'task', ident, 'will run for', round(delay, 1), 'sec'

        time.sleep(delay)

        if verbose:

            print 'task', ident, 'entering barrier', i

        bar.enter()

        if verbose:

            print 'task', ident, 'leaving barrier', i

    mutex.acquire()

    running -= 1

    # Must release mutex before releasing done, else the main thread can

    # exit and set mutex to None as part of global teardown; then

    # mutex.release() raises AttributeError.

    finished = running == 0

    mutex.release()

    if finished:

        done.release()

print '\n*** Barrier Test ***'

if done.acquire(0):

    raise ValueError, "'done' should have remained acquired"

bar = barrier(numtasks)

running = numtasks

for i in range(numtasks):

    thread.start_new_thread(task2, (i,))

done.acquire()

print 'all tasks done'

# not all platforms support changing thread stack size

print '\n*** Changing thread stack size ***'

if thread.stack_size() != 0:

    raise ValueError, "initial stack_size not 0"

thread.stack_size(0)

if thread.stack_size() != 0:

    raise ValueError, "stack_size not reset to default"

from os import name as os_name

if os_name in ("nt", "os2", "posix"):

    tss_supported = 1

    try:

        thread.stack_size(4096)

    except ValueError:

        print 'caught expected ValueError setting stack_size(4096)'

    except thread.error:

        tss_supported = 0

        print 'platform does not support changing thread stack size'

    if tss_supported:

        failed = lambda s, e: s != e

        fail_msg = "stack_size(%d) failed - should succeed"

        for tss in (262144, 0x100000, 0):

            thread.stack_size(tss)

            if failed(thread.stack_size(), tss):

                raise ValueError, fail_msg % tss

            print 'successfully set stack_size(%d)' % tss

        for tss in (262144, 0x100000):

            print 'trying stack_size = %d' % tss

            next_ident = 0

            for i in range(numtasks):

                newtask()

            print 'waiting for all tasks to complete'

            done.acquire()

            print 'all tasks done'

        # reset stack size to default

        thread.stack_size(0)