codekingpro/portable-devtools

1import eventlet2from eventlet.hubs import get_hub3import six4__select = eventlet.patcher.original('select')5error = __select.error6 7 8__patched__ = ['select']9__deleted__ = ['devpoll', 'poll', 'epoll', 'kqueue', 'kevent']10 11 12def get_fileno(obj):13    # The purpose of this function is to exactly replicate14    # the behavior of the select module when confronted with15    # abnormal filenos; the details are extensively tested in16    # the stdlib test/test_select.py.17    try:18        f = obj.fileno19    except AttributeError:20        if not isinstance(obj, six.integer_types):21            raise TypeError("Expected int or long, got %s" % type(obj))22        return obj23    else:24        rv = f()25        if not isinstance(rv, six.integer_types):26            raise TypeError("Expected int or long, got %s" % type(rv))27        return rv28 29 30def select(read_list, write_list, error_list, timeout=None):31    # error checking like this is required by the stdlib unit tests32    if timeout is not None:33        try:34            timeout = float(timeout)35        except ValueError:36            raise TypeError("Expected number for timeout")37    hub = get_hub()38    timers = []39    current = eventlet.getcurrent()40    assert hub.greenlet is not current, 'do not call blocking functions from the mainloop'41    ds = {}42    for r in read_list:43        ds[get_fileno(r)] = {'read': r}44    for w in write_list:45        ds.setdefault(get_fileno(w), {})['write'] = w46    for e in error_list:47        ds.setdefault(get_fileno(e), {})['error'] = e48 49    listeners = []50 51    def on_read(d):52        original = ds[get_fileno(d)]['read']53        current.switch(([original], [], []))54 55    def on_write(d):56        original = ds[get_fileno(d)]['write']57        current.switch(([], [original], []))58 59    def on_timeout2():60        current.switch(([], [], []))61 62    def on_timeout():63        # ensure that BaseHub.run() has a chance to call self.wait()64        # at least once before timed out.  otherwise the following code65        # can time out erroneously.66        #67        # s1, s2 = socket.socketpair()68        # print(select.select([], [s1], [], 0))69        timers.append(hub.schedule_call_global(0, on_timeout2))70 71    if timeout is not None:72        timers.append(hub.schedule_call_global(timeout, on_timeout))73    try:74        for k, v in six.iteritems(ds):75            if v.get('read'):76                listeners.append(hub.add(hub.READ, k, on_read, current.throw, lambda: None))77            if v.get('write'):78                listeners.append(hub.add(hub.WRITE, k, on_write, current.throw, lambda: None))79        try:80            return hub.switch()81        finally:82            for l in listeners:83                hub.remove(l)84    finally:85        for t in timers:86            t.cancel()87