module DEBUGGER__::MultiProcessGroup

# File debug-1.9.1/lib/debug/session.rb, line 2065
def after_fork child: true
  if child || !@lock_file
    @m = Mutex.new unless @m
    @m.synchronize do
      @lock_level = 0
      @lock_file = open(@lock_tempfile.path, 'w')
    end
  end
end

# File debug-1.9.1/lib/debug/session.rb, line 2075
def info msg
  DEBUGGER__.info "#{msg} (#{@lock_level})" #  #{caller.first(1).map{|bt| bt.sub(__dir__, '')}}"
end

# File debug-1.9.1/lib/debug/session.rb, line 2117
def lock
  unless trylock
    @m.synchronize do
      if locked?
        lock_level_up
      else
        info "Lock: block"
        @lock_file.flock(File::LOCK_EX)
        lock_level_up
      end
    end

    info "Lock: success"
  end
end

# File debug-1.9.1/lib/debug/session.rb, line 2079
def locked?
  # DEBUGGER__.debug{ "locked? #{@lock_level}" }
  @lock_level > 0
end

# File debug-1.9.1/lib/debug/session.rb, line 2062
def multi_process!
end

# File debug-1.9.1/lib/debug/session.rb, line 2142
def sync &b
  info "sync"

  lock
  begin
    b.call if b
  ensure
    unlock
  end
end

# File debug-1.9.1/lib/debug/session.rb, line 2133
def unlock
  @m.synchronize do
    raise "lock file is not opened (#{@lock_file.inspect})" if @lock_file.closed?
    lock_level_down
    @lock_file.flock(File::LOCK_UN) unless locked?
    info "Unlocked"
  end
end

# File debug-1.9.1/lib/debug/session.rb, line 2089
        def lock_level_down
  raise unless @m.owned?
  raise "@lock_level underflow: #{@lock_level}" if @lock_level < 1
  @lock_level -= 1
end

# File debug-1.9.1/lib/debug/session.rb, line 2084
        def lock_level_up
  raise unless @m.owned?
  @lock_level += 1
end

# File debug-1.9.1/lib/debug/session.rb, line 2095
        def trylock
  @m.synchronize do
    if locked?
      lock_level_up
      info "Try lock, already locked"
      true
    else
      case r = @lock_file.flock(File::LOCK_EX | File::LOCK_NB)
      when 0
        lock_level_up
        info "Try lock with file: success"
        true
      when false
        info "Try lock with file: failed"
        false
      else
        raise "unknown flock result: #{r.inspect}"
      end
    end
  end
end