/
fork_tracker.rb
71 lines (62 loc) · 1.39 KB
/
fork_tracker.rb
1
2
3
4
5
6
7
8
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
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
# frozen_string_literal: true
module ActiveSupport
module ForkTracker # :nodoc:
module ModernCoreExt
def _fork
pid = super
if pid == 0
ForkTracker.check!
end
pid
end
end
module CoreExt
def fork(...)
if block_given?
super do
ForkTracker.check!
yield
end
else
unless pid = super
ForkTracker.check!
end
pid
end
end
end
module CoreExtPrivate
include CoreExt
private :fork
end
@pid = Process.pid
@callbacks = []
class << self
def check!
new_pid = Process.pid
if @pid != new_pid
@callbacks.each(&:call)
@pid = new_pid
end
end
def hook!
if Process.respond_to?(:_fork) # Ruby 3.1+
::Process.singleton_class.prepend(ModernCoreExt)
elsif Process.respond_to?(:fork)
::Object.prepend(CoreExtPrivate) if RUBY_VERSION < "3.0"
::Kernel.prepend(CoreExtPrivate)
::Kernel.singleton_class.prepend(CoreExt)
::Process.singleton_class.prepend(CoreExt)
end
end
def after_fork(&block)
@callbacks << block
block
end
def unregister(callback)
@callbacks.delete(callback)
end
end
end
end
ActiveSupport::ForkTracker.hook!