Class: DeepTest::Warlock

Inherits:
Object
  • Object
show all
Defined in:
lib/deep_test/warlock.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Warlock

Returns a new instance of Warlock.



3
4
5
6
7
 
# File 'lib/deep_test/warlock.rb', line 3

def initialize
  @demons_semaphore = Mutex.new
  @demons = []
  @reapers = []
end

Instance Method Details

#any_running? ⇒ Boolean

Returns:

  • (Boolean) 


86
87
88
89
90
 
# File 'lib/deep_test/warlock.rb', line 86

def any_running?
  @demons_semaphore.synchronize do
    @demons.any? {|name, pid| running?(pid)}
  end
end

#demon_count ⇒ Object 



49
50
51
52
53
 
# File 'lib/deep_test/warlock.rb', line 49

def demon_count
  @demons_semaphore.synchronize do
    @demons.size
  end
end

#exit_when_none_running ⇒ Object 



76
77
78
79
80
81
82
83
84
 
# File 'lib/deep_test/warlock.rb', line 76

def exit_when_none_running
  Thread.new do
    loop do
      Thread.pass
      exit(0) unless any_running?
      sleep(0.01)
    end
  end
end

#running?(pid) ⇒ Boolean

stolen from daemons

Returns:

  • (Boolean) 


93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
 
# File 'lib/deep_test/warlock.rb', line 93

def running?(pid)
  # Check if process is in existence
  # The simplest way to do this is to send signal '0'
  # (which is a single system call) that doesn't actually
  # send a signal
  begin
    Process.kill(0, pid)
    return true
  rescue Errno::ESRCH
    return false
  rescue ::Exception   # for example on EPERM (process exists but does not belong to us)
    return true
  #rescue Errno::EPERM
  #  return false
  end
end

#start(name, &block) ⇒ Object 



9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
 
# File 'lib/deep_test/warlock.rb', line 9

def start(name, &block)
  # Not synchronizing for the fork seems to cause
  # random errors (Bus Error, Segfault, and GC non-object)
  # in RemoteWorkerServer processes.
  #
  begin
    pid = nil
    @demons_semaphore.synchronize do 
      pid = DeepTest.drb_safe_fork do
        # Fork leaves the semaphore locked and we'll never make it
        # to end of synchronize block.
        #
        # The Ruby 1.8.6 C mutex implementation automatically treats
        # a mutex locked by a dead thread as unlocked and will raise
        # an error if we try to unlock it from this thread.
        #
        @demons_semaphore.unlock if @demons_semaphore.locked?

        begin
          yield
        rescue Exception => e
          DeepTest.logger.debug "Exception in #{name} (#{Process.pid}): #{e.message}"
          raise
        end

        exit
      end

      raise "fatal: fork returned nil" if pid.nil?
      add_demon name, pid
    end

    launch_reaper_thread name, pid

  rescue => e
    puts "exception starting #{name}: #{e}"
    puts "\t" + e.backtrace.join("\n\t")
  end
end

#stop_all ⇒ Object 



55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
 
# File 'lib/deep_test/warlock.rb', line 55

def stop_all
  DeepTest.logger.debug("stopping all demons")
  receivers = @demons_semaphore.synchronize do
    @demons.reverse
  end

  receivers.reverse.each do |demon|
    name, pid = demon
    if running?(pid)
      DeepTest.logger.debug("Sending SIGTERM to #{name}, #{pid}")
      Process.kill("TERM", pid)
    end
  end
  DeepTest.logger.debug("Warlock: Stopped all receivers")

  DeepTest.logger.debug("waiting for reapers")
  @reapers.each {|r| r.join}

  DeepTest.logger.debug("Warlock: done reaping processes")
end