1# Copyright 2015 gRPC authors. 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14 15# GRPC contains the General RPC module. 16module GRPC 17 # Notifier is useful high-level synchronization primitive. 18 class Notifier 19 attr_reader :payload, :notified 20 alias_method :notified?, :notified 21 22 def initialize 23 @mutex = Mutex.new 24 @cvar = ConditionVariable.new 25 @notified = false 26 @payload = nil 27 end 28 29 def wait 30 @mutex.synchronize do 31 @cvar.wait(@mutex) until notified? 32 end 33 end 34 35 def notify(payload) 36 @mutex.synchronize do 37 return Error.new('already notified') if notified? 38 @payload = payload 39 @notified = true 40 @cvar.signal 41 return nil 42 end 43 end 44 end 45end 46