Merge ff268ee into 6db48e7

lib/resque/child_process.rb

@@ -1,4 +1,5 @@
 require 'resque/worker_hooks'
+require 'resque/signal_trapper'
 
 module Resque
   # A child process processes a single job. It is created by a Resque Worker.
@@ -46,15 +47,12 @@ def reconnect
     end
 
     def unregister_signal_handlers
-      trap('TERM') { raise TermException.new("SIGTERM") }
-      trap('INT', 'DEFAULT')
+      SignalTrapper.trap('TERM') { raise TermException.new("SIGTERM") }
+      SignalTrapper.trap('INT', 'DEFAULT')
 
-      begin
-        trap('QUIT', 'DEFAULT')
-        trap('USR1', 'DEFAULT')
-        trap('USR2', 'DEFAULT')
-      rescue ArgumentError
-      end
+      SignalTrapper.trap_or_warn('QUIT', 'DEFAULT')
+      SignalTrapper.trap_or_warn('USR1', 'DEFAULT')
+      SignalTrapper.trap_or_warn('USR2', 'DEFAULT')
     end
 
     # Kills the forked child immediately with minimal remorse. The job it

lib/resque/ioawaiter.rb

@@ -1,16 +1,17 @@
+require 'resque/signal_trapper'
 module Resque
   class IOAwaiter
     def await
       rd, wr = IO.pipe
-      trap('CONT') {
+      SignalTrapper.trap('CONT') {
         wr.write 'x'
         wr.close
       }
 
       rd.read 1
       rd.close
 
-      trap('CONT', 'DEFAULT')
+      SignalTrapper.trap('CONT', 'DEFAULT')
     end
   end
 end

lib/resque/signal_trapper.rb

@@ -0,0 +1,19 @@
+module Resque
+  # Helper for trapping signals.
+  #
+  #   Trap a signal (accepts same params as Signal#trap):
+  #     SignalTrapper.trap('INT') { do_stuff }
+  #   Trap a signal, but don't raise exception if unsupported signal:
+  #     SignalTrapper.trap_or_warn('INT') { do_stuff }
+  module SignalTrapper
+    def self.trap(*args, &block)
+      Signal.trap(*args, &block)
+    end
+
+    def self.trap_or_warn(*args, &block)
+      trap(*args, &block)
+    rescue ArgumentError => e
+      warn e
+    end
+  end
+end

lib/resque/worker.rb

@@ -11,6 +11,7 @@
 require 'resque/backend'
 require 'resque/ioawaiter'
 require 'resque/options'
+require 'resque/signal_trapper'
 
 module Resque
   # A Resque Worker processes jobs. On platforms that support fork(2),
@@ -310,27 +311,20 @@ def enable_gc_optimizations
 
     # Registers the various signal handlers a worker responds to.
     #
-    # TERM: Shutdown immediately, stop processing jobs.
-    #  INT: Shutdown immediately, stop processing jobs.
+    # TERM/INT: Shutdown immediately, stop processing jobs.
     # QUIT: Shutdown after the current job has finished processing.
     # USR1: Kill the forked child immediately, continue processing jobs.
     # USR2: Don't process any new jobs
-    # CONT: Start processing jobs again after a USR2
     def register_signal_handlers
-      trap('TERM') { shutdown!  }
-      trap('INT')  { shutdown!  }
-
-      begin
-        # The signal QUIT & USR1 is in use by the JVM and will not work correctly on jRuby
-        unless jruby?
-          trap('QUIT') { shutdown   }
-          trap('USR1') { @child.kill }
-        end
-        trap('USR2') { pause_processing }
-        trap('CONT') { unpause_processing }
-      rescue ArgumentError
-        warn "Signals QUIT, USR1, USR2, and/or CONT not supported."
+      SignalTrapper.trap('TERM') { shutdown! }
+      SignalTrapper.trap('INT')  { shutdown! }
+
+      # these signals are in use by the JVM and will not work correctly on jRuby
+      unless jruby?
+        SignalTrapper.trap_or_warn('QUIT') { shutdown }
+        SignalTrapper.trap_or_warn('USR1') { @child.kill }
       end
+      SignalTrapper.trap_or_warn('USR2') { pause_processing }
 
       logger.debug "Registered signals"
     end
@@ -341,14 +335,12 @@ def processed!
       Stat << "processed:#{self}"
     end
 
-
     # Tells Redis we've failed a job.
     def failed!
       Stat << "failed"
       Stat << "failed:#{self}"
     end
 
-
     # Given a string, sets the procline ($0) and logs.
     # Procline is always in the format of:
     #   resque-VERSION: STRING