# -*- coding: utf-8 -*- {{{
# vim: set fenc=utf-8 ft=python sw=4 ts=4 sts=4 et:

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from gevent.lock import BoundedSemaphore, DummySemaphore
from contextlib import contextmanager

_socket_lock = None


def configure_socket_lock(max_connections=0):
    global _socket_lock
    if _socket_lock is not None:
        raise RuntimeError("socket_lock already configured!")
    if max_connections < 1:
        _socket_lock = DummySemaphore()
    else:
        _socket_lock = BoundedSemaphore(max_connections)


@contextmanager
def socket_lock():
    global _socket_lock
    if _socket_lock is None:
        raise RuntimeError("socket_lock not configured!")
    _socket_lock.acquire()
    try:
        yield
    finally:
        _socket_lock.release()


_publish_lock = None


def configure_publish_lock(max_connections=0):
    global _publish_lock
    if _publish_lock is not None:
        raise RuntimeError("publish_lock already configured!")
    if max_connections < 1:
        _publish_lock = DummySemaphore()
    else:
        _publish_lock = BoundedSemaphore(max_connections)


@contextmanager
def publish_lock():
    global _publish_lock
    if _publish_lock is None:
        raise RuntimeError("publish_lock not configured!")
    _publish_lock.acquire()
    try:
        yield
    finally:
        _publish_lock.release()
