Adds monitor functionality to an arbitrary object by mixing the module with
include
. For example:
require 'monitor.rb' buf = [] buf.extend(MonitorMixin) empty_cond = buf.new_cond # consumer Thread.start do loop do buf.synchronize do empty_cond.wait_while { buf.empty? } print buf.shift end end end # producer while line = ARGF.gets buf.synchronize do buf.push(line) empty_cond.signal end end
The consumer thread waits for the producer thread to push a line to buf while buf.empty?, and the producer thread (main thread) reads a line from ARGF and push it to buf, then call empty_cond.signal.
Enters exclusive section.
# File monitor.rb, line 212 def mon_enter Thread.critical = true mon_acquire(@mon_entering_queue) @mon_count += 1 ensure Thread.critical = false end
Leaves exclusive section.
# File monitor.rb, line 223 def mon_exit mon_check_owner Thread.critical = true @mon_count -= 1 if @mon_count == 0 mon_release end Thread.critical = false Thread.pass end
Enters exclusive section and executes the block. Leaves the exclusive
section automatically when the block exits. See example under
MonitorMixin
.
# File monitor.rb, line 239 def mon_synchronize mon_enter begin yield ensure mon_exit end end
Attempts to enter exclusive section. Returns false
if lock
fails.
# File monitor.rb, line 193 def mon_try_enter result = false Thread.critical = true if @mon_owner.nil? @mon_owner = Thread.current end if @mon_owner == Thread.current @mon_count += 1 result = true end Thread.critical = false return result end