def ChannelWait(chan, timeout = None):
"""Receive on a channel, but with a timeout. The optional timeout is specified
in seconds. Returns (bool, result) with the bool being true if there
was no timeout.
"""
if timeout is None:
return (True, chan.receive())
waiting_tasklet = stackless.getcurrent()
def break_wait():
try:
blue.pyos.synchro.SleepWallclock(int(timeout * 1000))
except _TimeoutError:
return
with atomic():
if waiting_tasklet and waiting_tasklet.blocked:
waiting_tasklet.raise_exception(_TimeoutError)
with atomic():
breaker = new(break_wait)
try:
result = chan.receive()
if breaker.blocked:
breaker.raise_exception(_TimeoutError)
return (True, result)
except _TimeoutError:
return (False, None)
finally:
waiting_tasklet = None
def ChannelWait(chan, timeout = None):
if timeout is None:
return (True, chan.receive())
waiting_tasklet = stackless.getcurrent()
def break_wait():
try:
blue.pyos.synchro.SleepWallclock(int(timeout * 1000))
except _TimeoutError:
return
with atomic():
if waiting_tasklet and waiting_tasklet.blocked:
waiting_tasklet.raise_exception(_TimeoutError)
with atomic():
breaker = new(break_wait)
try:
result = chan.receive()
if breaker.blocked:
breaker.raise_exception(_TimeoutError)
return (True, result)
except _TimeoutError:
return (False, None)
finally:
waiting_tasklet = None
def ChannelWait(chan, timeout=None):
if timeout is None:
return (True, chan.receive())
waiting_tasklet = stackless.getcurrent()
def break_wait():
try:
blue.pyos.synchro.SleepWallclock(int(timeout * 1000))
except _TimeoutError:
return
with atomic():
if waiting_tasklet and waiting_tasklet.blocked:
waiting_tasklet.raise_exception(_TimeoutError)
with atomic():
breaker = new(break_wait)
try:
result = chan.receive()
if breaker.blocked:
breaker.raise_exception(_TimeoutError)
return (True, result)
except _TimeoutError:
return (False, None)
finally:
waiting_tasklet = None
def __call__(self, *args, **kwds):
with atomic():
self.tasklet = stackless.getcurrent()
try:
self.initiate_call(args, kwds)
return self.wait()
finally:
self.channel.close()
self.tasklet = None
def break_wait():
try:
blue.pyos.synchro.SleepWallclock(int(timeout * 1000))
except _TimeoutError:
return
with atomic():
if waiting_tasklet and waiting_tasklet.blocked:
waiting_tasklet.raise_exception(_TimeoutError)
def release(self, override = False):
with atomic():
if self.strict and not override:
if stackless.getcurrent() not in self.threads:
raise RuntimeError, 'wrong tasklet releasing strict semaphore'
self.count += 1
self.threads.remove(stackless.getcurrent())
self.lockedWhen = None
self._pump()
def break_wait():
try:
blue.pyos.synchro.SleepWallclock(int(timeout * 1000))
except _TimeoutError:
return
with atomic():
if waiting_tasklet and waiting_tasklet.blocked:
waiting_tasklet.raise_exception(_TimeoutError)
def release(self, override = False):
with atomic():
if self.strict and not override:
if stackless.getcurrent() not in self.threads:
raise RuntimeError, 'wrong tasklet releasing strict semaphore'
self.count += 1
self.threads.remove(stackless.getcurrent())
self.lockedWhen = None
self._pump()
def try_acquire(self):
with atomic():
if self.strict:
if self.count <= 0 and stackless.getcurrent() in self.threads:
raise RuntimeError, 'tasklet deadlock, acquiring tasklet holds strict semaphore'
if self.count > 0:
self.count -= 1
self.lockedWhen = blue.os.GetWallclockTime()
self.threads.append(stackless.getcurrent())
return True
return False
def try_acquire(self):
with atomic():
if self.strict:
if self.count <= 0 and stackless.getcurrent() in self.threads:
raise RuntimeError, 'tasklet deadlock, acquiring tasklet holds strict semaphore'
if self.count > 0:
self.count -= 1
self.lockedWhen = blue.os.GetWallclockTime()
self.threads.append(stackless.getcurrent())
return True
return False
def acquire(self):
with atomic():
if self.strict:
if self.count <= 0 and stackless.getcurrent() in self.threads:
raise RuntimeError, 'tasklet deadlock, acquiring tasklet holds strict semaphore'
while self.count == 0:
self.n_waiting += 1
try:
self.waiting.receive()
except:
self._safe_pump()
raise
finally:
self.n_waiting -= 1
self.count -= 1
self.lockedWhen = blue.os.GetWallclockTime()
self.threads.append(stackless.getcurrent())
def acquire(self):
with atomic():
if self.strict:
if self.count <= 0 and stackless.getcurrent() in self.threads:
raise RuntimeError, 'tasklet deadlock, acquiring tasklet holds strict semaphore'
while self.count == 0:
self.n_waiting += 1
try:
self.waiting.receive()
except:
self._safe_pump()
raise
finally:
self.n_waiting -= 1
self.count -= 1
self.lockedWhen = blue.os.GetWallclockTime()
self.threads.append(stackless.getcurrent())
def cancel(self, *args):
"""rase the CancelledError on any waiting tasklet"""
with atomic():
if self.tasklet:
self.tasklet.throw(CancelledError, args)
