mirror of
https://github.com/ruby/ruby.git
synced 2022-11-09 12:17:21 -05:00
739fdb7ff0
RDoc says nothing about them. Added an example that ConditionVariable#wait can be woken up by ConditionVariable#signal, instead.
40 lines
1 KiB
Ruby
40 lines
1 KiB
Ruby
require_relative '../../spec_helper'
|
|
require 'thread'
|
|
|
|
describe "ConditionVariable#broadcast" do
|
|
it "releases all threads waiting in line for this resource" do
|
|
m = Mutex.new
|
|
cv = ConditionVariable.new
|
|
threads = []
|
|
r1 = []
|
|
r2 = []
|
|
|
|
# large number to attempt to cause race conditions
|
|
100.times do |i|
|
|
threads << Thread.new(i) do |tid|
|
|
m.synchronize do
|
|
r1 << tid
|
|
cv.wait(m)
|
|
r2 << tid
|
|
end
|
|
end
|
|
end
|
|
|
|
# wait for all threads to acquire the mutex the first time
|
|
Thread.pass until m.synchronize { r1.size == threads.size }
|
|
# wait until all threads are sleeping (ie waiting)
|
|
Thread.pass until threads.all?(&:stop?)
|
|
|
|
r2.should be_empty
|
|
m.synchronize do
|
|
cv.broadcast
|
|
end
|
|
|
|
threads.each {|t| t.join }
|
|
|
|
# ensure that all threads that enter cv.wait are released
|
|
r2.sort.should == r1.sort
|
|
# note that order is not specified as broadcast results in a race
|
|
# condition on regaining the lock m
|
|
end
|
|
end
|