#--
# mutex_m.rb -
# $Release Version: 3.0$
# $Revision: 1.7 $
# $Date: 1998/02/27 04:28:57 $
# Original from mutex.rb
# by Keiju ISHITSUKA(keiju@ishitsuka.com)
# modified by matz
# patched by akira yamada
#++
#
# == Usage
#
# Extend an object and use it like a Mutex object:
#
# require "mutex_m.rb"
# obj = Object.new
# obj.extend Mutex_m
# # ...
#
# Or, include Mutex_m in a class to have its instances behave like a Mutex
# object:
#
# class Foo
# include Mutex_m
# # ...
# end
#
# obj = Foo.new
module Mutex_m
def Mutex_m.define_aliases(cl)
cl.module_eval %q{
alias locked? mu_locked?
alias lock mu_lock
alias unlock mu_unlock
alias try_lock mu_try_lock
alias synchronize mu_synchronize
}
end
def Mutex_m.append_features(cl)
super
define_aliases(cl) unless cl.instance_of?(Module)
end
def Mutex_m.extend_object(obj)
super
obj.mu_extended
end
def mu_extended
unless (defined? locked? and
defined? lock and
defined? unlock and
defined? try_lock and
defined? synchronize)
Mutex_m.define_aliases(class<<self;self;end)
end
mu_initialize
end
# locking
def mu_synchronize
begin
mu_lock
yield
ensure
mu_unlock
end
end
def mu_locked?
@mu_locked
end
def mu_try_lock
result = false
Thread.critical = true
unless @mu_locked
@mu_locked = true
result = true
end
Thread.critical = false
result
end
def mu_lock
while (Thread.critical = true; @mu_locked)
@mu_waiting.push Thread.current
Thread.stop
end
@mu_locked = true
Thread.critical = false
self
end
def mu_unlock
return unless @mu_locked
Thread.critical = true
wait = @mu_waiting
@mu_waiting = []
@mu_locked = false
Thread.critical = false
for w in wait
w.run
end
self
end
private
def mu_initialize
@mu_waiting = []
@mu_locked = false;
end
def initialize(*args)
mu_initialize
super
end
end
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