AlkantarClanX12
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# # sync.rb - 2 phase lock with counter # $Release Version: 1.0$ # $Revision: 22457 $ # $Date: 2009-02-20 01:41:12 +0900 (Fri, 20 Feb 2009) $ # by Keiju ISHITSUKA(keiju@ishitsuka.com) # # -- # Sync_m, Synchronizer_m # Usage: # obj.extend(Sync_m) # or # class Foo # include Sync_m # : # end # # Sync_m#sync_mode # Sync_m#sync_locked?, locked? # Sync_m#sync_shared?, shared? # Sync_m#sync_exclusive?, sync_exclusive? # Sync_m#sync_try_lock, try_lock # Sync_m#sync_lock, lock # Sync_m#sync_unlock, unlock # # Sync, Synchronicer: # include Sync_m # Usage: # sync = Sync.new # # Sync#mode # Sync#locked? # Sync#shared? # Sync#exclusive? # Sync#try_lock(mode) -- mode = :EX, :SH, :UN # Sync#lock(mode) -- mode = :EX, :SH, :UN # Sync#unlock # Sync#synchronize(mode) {...} # # unless defined? Thread fail "Thread not available for this ruby interpreter" end module Sync_m RCS_ID='-$Header$-' # lock mode UN = :UN SH = :SH EX = :EX # exceptions class Err < StandardError def Err.Fail(*opt) Thread.critical = false fail self, sprintf(self::Message, *opt) end class UnknownLocker < Err Message = "Thread(%s) not locked." def UnknownLocker.Fail(th) super(th.inspect) end end class LockModeFailer < Err Message = "Unknown lock mode(%s)" def LockModeFailer.Fail(mode) if mode.id2name mode = id2name end super(mode) end end end def Sync_m.define_aliases(cl) cl.module_eval %q{ alias locked? sync_locked? alias shared? sync_shared? alias exclusive? sync_exclusive? alias lock sync_lock alias unlock sync_unlock alias try_lock sync_try_lock alias synchronize sync_synchronize } end def Sync_m.append_features(cl) super unless cl.instance_of?(Module) # do nothing for Modules # make aliases and include the proper module. define_aliases(cl) end end def Sync_m.extend_object(obj) super obj.sync_extended end def sync_extended unless (defined? locked? and defined? shared? and defined? exclusive? and defined? lock and defined? unlock and defined? try_lock and defined? synchronize) Sync_m.define_aliases(class<<self;self;end) end sync_initialize end # accessing def sync_locked? sync_mode != UN end def sync_shared? sync_mode == SH end def sync_exclusive? sync_mode == EX end # locking methods. def sync_try_lock(mode = EX) return unlock if mode == UN Thread.critical = true ret = sync_try_lock_sub(mode) Thread.critical = false ret end def sync_lock(m = EX) return unlock if m == UN until (Thread.critical = true; sync_try_lock_sub(m)) if sync_sh_locker[Thread.current] sync_upgrade_waiting.push [Thread.current, sync_sh_locker[Thread.current]] sync_sh_locker.delete(Thread.current) else sync_waiting.push Thread.current end Thread.stop end Thread.critical = false self end def sync_unlock(m = EX) Thread.critical = true if sync_mode == UN Thread.critical = false Err::UnknownLocker.Fail(Thread.current) end m = sync_mode if m == EX and sync_mode == SH runnable = false case m when UN Thread.critical = false Err::UnknownLocker.Fail(Thread.current) when EX if sync_ex_locker == Thread.current if (self.sync_ex_count = sync_ex_count - 1) == 0 self.sync_ex_locker = nil if sync_sh_locker.include?(Thread.current) self.sync_mode = SH else self.sync_mode = UN end runnable = true end else Err::UnknownLocker.Fail(Thread.current) end when SH if (count = sync_sh_locker[Thread.current]).nil? Err::UnknownLocker.Fail(Thread.current) else if (sync_sh_locker[Thread.current] = count - 1) == 0 sync_sh_locker.delete(Thread.current) if sync_sh_locker.empty? and sync_ex_count == 0 self.sync_mode = UN runnable = true end end end end if runnable if sync_upgrade_waiting.size > 0 for k, v in sync_upgrade_waiting sync_sh_locker[k] = v end wait = sync_upgrade_waiting self.sync_upgrade_waiting = [] Thread.critical = false for w, v in wait w.run end else wait = sync_waiting self.sync_waiting = [] Thread.critical = false for w in wait w.run end end end Thread.critical = false self end def sync_synchronize(mode = EX) begin sync_lock(mode) yield ensure sync_unlock end end attr :sync_mode, true attr :sync_waiting, true attr :sync_upgrade_waiting, true attr :sync_sh_locker, true attr :sync_ex_locker, true attr :sync_ex_count, true private def sync_initialize @sync_mode = UN @sync_waiting = [] @sync_upgrade_waiting = [] @sync_sh_locker = Hash.new @sync_ex_locker = nil @sync_ex_count = 0 end def initialize(*args) sync_initialize super end def sync_try_lock_sub(m) case m when SH case sync_mode when UN self.sync_mode = m sync_sh_locker[Thread.current] = 1 ret = true when SH count = 0 unless count = sync_sh_locker[Thread.current] sync_sh_locker[Thread.current] = count + 1 ret = true when EX # in EX mode, lock will upgrade to EX lock if sync_ex_locker == Thread.current self.sync_ex_count = sync_ex_count + 1 ret = true else ret = false end end when EX if sync_mode == UN or sync_mode == SH && sync_sh_locker.size == 1 && sync_sh_locker.include?(Thread.current) self.sync_mode = m self.sync_ex_locker = Thread.current self.sync_ex_count = 1 ret = true elsif sync_mode == EX && sync_ex_locker == Thread.current self.sync_ex_count = sync_ex_count + 1 ret = true else ret = false end else Thread.critical = false Err::LockModeFailer.Fail mode end return ret end end Synchronizer_m = Sync_m class Sync #Sync_m.extend_class self include Sync_m def initialize super end end Synchronizer = Sync