JezK
Edit File: thwait.rb
# # thwait.rb - thread synchronization class # $Release Version: 0.9 $ # $Revision: 1.3 $ # $Date: 1998/06/26 03:19:34 $ # by Keiju ISHITSUKA(Nihpon Rational Software Co.,Ltd.) # # -- # feature: # provides synchronization for multiple threads. # # class methods: # * ThreadsWait.all_waits(thread1,...) # waits until all of specified threads are terminated. # if a block is supplied for the method, evaluates it for # each thread termination. # * th = ThreadsWait.new(thread1,...) # creates synchronization object, specifying thread(s) to wait. # # methods: # * th.threads # list threads to be synchronized # * th.empty? # is there any thread to be synchronized. # * th.finished? # is there already terminated thread. # * th.join(thread1,...) # wait for specified thread(s). # * th.join_nowait(threa1,...) # specifies thread(s) to wait. non-blocking. # * th.next_wait # waits until any of specified threads is terminated. # * th.all_waits # waits until all of specified threads are terminated. # if a block is supplied for the method, evaluates it for # each thread termination. # require "thread.rb" require "e2mmap.rb" # # This class watches for termination of multiple threads. Basic functionality # (wait until specified threads have terminated) can be accessed through the # class method ThreadsWait::all_waits. Finer control can be gained using # instance methods. # # Example: # # ThreadsWait.all_wait(thr1, thr2, ...) do |t| # STDERR.puts "Thread #{t} has terminated." # end # class ThreadsWait RCS_ID='-$Id: thwait.rb,v 1.3 1998/06/26 03:19:34 keiju Exp keiju $-' Exception2MessageMapper.extend_to(binding) def_exception("ErrNoWaitingThread", "No threads for waiting.") def_exception("ErrNoFinishedThread", "No finished threads.") # # Waits until all specified threads have terminated. If a block is provided, # it is executed for each thread termination. # def ThreadsWait.all_waits(*threads) # :yield: thread tw = ThreadsWait.new(*threads) if block_given? tw.all_waits do |th| yield th end else tw.all_waits end end # # Creates a ThreadsWait object, specifying the threads to wait on. # Non-blocking. # def initialize(*threads) @threads = [] @wait_queue = Queue.new join_nowait(*threads) unless threads.empty? end # Returns the array of threads in the wait queue. attr :threads # # Returns +true+ if there are no threads to be synchronized. # def empty? @threads.empty? end # # Returns +true+ if any thread has terminated. # def finished? !@wait_queue.empty? end # # Waits for specified threads to terminate, and returns when one of # the threads terminated. # def join(*threads) join_nowait(*threads) next_wait end # # Specifies the threads that this object will wait for, but does not actually # wait. # def join_nowait(*threads) threads.flatten! @threads.concat threads for th in threads Thread.start(th) do |t| begin t.join ensure @wait_queue.push t end end end end # # Waits until any of the specified threads has terminated, and returns the one # that does. # # If there is no thread to wait, raises +ErrNoWaitingThread+. If +nonblock+ # is true, and there is no terminated thread, raises +ErrNoFinishedThread+. # def next_wait(nonblock = nil) ThreadsWait.fail ErrNoWaitingThread if @threads.empty? begin @threads.delete(th = @wait_queue.pop(nonblock)) th rescue ThreadError ThreadsWait.fail ErrNoFinishedThread end end # # Waits until all of the specified threads are terminated. If a block is # supplied for the method, it is executed for each thread termination. # # Raises exceptions in the same manner as +next_wait+. # def all_waits until @threads.empty? th = next_wait yield th if block_given? end end end ThWait = ThreadsWait # Documentation comments: # - Source of documentation is evenly split between Nutshell, existing # comments, and my own rephrasing. # - I'm not particularly confident that the comments are all exactly correct. # - The history, etc., up the top appears in the RDoc output. Perhaps it would # be better to direct that not to appear, and put something else there # instead.