Class: SupportTableCache::FiberLocals

Inherits:
Object
  • Object
show all
Defined in:
lib/support_table_cache/fiber_locals.rb

Overview

Utility class for managing fiber-local variables. This implementation does not pollute the global namespace.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ FiberLocals 



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# File 'lib/support_table_cache/fiber_locals.rb', line 7

def initialize
  @mutex = Mutex.new
  @locals = {}
end

Instance Method Details

#[](key) ⇒ Object 



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# File 'lib/support_table_cache/fiber_locals.rb', line 12

def [](key)
  fiber_locals = nil
  @mutex.synchronize do
    fiber_locals = @locals[Fiber.current.object_id]
  end
  return nil if fiber_locals.nil?

  fiber_locals[key]
end

#with(key, value) ⇒ Object 



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# File 'lib/support_table_cache/fiber_locals.rb', line 22

def with(key, value)
  fiber_id = Fiber.current.object_id
  fiber_locals = nil
  previous_value = nil
  inited_vars = false

  begin
    @mutex.synchronize do
      fiber_locals = @locals[fiber_id]
      if fiber_locals.nil?
        fiber_locals = {}
        @locals[fiber_id] = fiber_locals
        inited_vars = true
      end
    end

    previous_value = fiber_locals[key]
    fiber_locals[key] = value

    yield
  ensure
    if inited_vars
      @mutex.synchronize do
        @locals.delete(fiber_id)
      end
    else
      fiber_locals[key] = previous_value
    end
  end
end