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-rw-r--r--lib/timeout.rb196
1 files changed, 112 insertions, 84 deletions
diff --git a/lib/timeout.rb b/lib/timeout.rb
index dc92964c0b..f50e706d4b 100644
--- a/lib/timeout.rb
+++ b/lib/timeout.rb
@@ -1,105 +1,133 @@
-#--
-# = timeout.rb
+# frozen_string_literal: false
+# Timeout long-running blocks
#
-# execution timeout
+# == Synopsis
#
-# = Copyright
-#
-# Copyright:: (C) 2000 Network Applied Communication Laboratory, Inc.
-# Copyright:: (C) 2000 Information-technology Promotion Agency, Japan
-#
-#++
-#
-# = Description
+# require 'timeout'
+# status = Timeout::timeout(5) {
+# # Something that should be interrupted if it takes more than 5 seconds...
+# }
#
-# A way of performing a potentially long-running operation in a thread, and
-# terminating it's execution if it hasn't finished within fixed amount of
-# time.
+# == Description
#
-# Previous versions of timeout didn't use a module for namespace. This version
-# provides both Timeout.timeout, and a backwards-compatible #timeout.
+# Timeout provides a way to auto-terminate a potentially long-running
+# operation if it hasn't finished in a fixed amount of time.
#
-# = Synopsis
+# Previous versions didn't use a module for namespacing, however
+# #timeout is provided for backwards compatibility. You
+# should prefer Timeout.timeout instead.
#
-# require 'timeout'
-# status = Timeout::timeout(5) {
-# # Something that should be interrupted if it takes too much time...
-# }
+# == Copyright
#
+# Copyright:: (C) 2000 Network Applied Communication Laboratory, Inc.
+# Copyright:: (C) 2000 Information-technology Promotion Agency, Japan
module Timeout
+ VERSION = "0.2.0".freeze
- ##
- # Raised by Timeout#timeout when the block times out.
+ # Raised by Timeout.timeout when the block times out.
+ class Error < RuntimeError
+ attr_reader :thread
- class Error<Interrupt
- end
-
- ##
- # Executes the method's block. If the block execution terminates before +sec+
- # seconds has passed, it returns true. If not, it terminates the execution
- # and raises +exception+ (which defaults to Timeout::Error).
- #
- # Note that this is both a method of module Timeout, so you can 'include
- # Timeout' into your classes so they have a #timeout method, as well as a
- # module method, so you can call it directly as Timeout.timeout().
+ def self.catch(*args)
+ exc = new(*args)
+ exc.instance_variable_set(:@thread, Thread.current)
+ exc.instance_variable_set(:@catch_value, exc)
+ ::Kernel.catch(exc) {yield exc}
+ end
- def timeout(sec, exception=Error)
- return yield if sec == nil or sec.zero?
- raise ThreadError, "timeout within critical session" if Thread.critical
- begin
- x = Thread.current
- y = Thread.start {
- sleep sec
- x.raise exception, "execution expired" if x.alive?
- }
- yield sec
- # return true
- ensure
- y.kill if y and y.alive?
+ def exception(*)
+ # TODO: use Fiber.current to see if self can be thrown
+ if self.thread == Thread.current
+ bt = caller
+ begin
+ throw(@catch_value, bt)
+ rescue UncaughtThrowError
+ end
+ end
+ super
end
end
- module_function :timeout
+ # :stopdoc:
+ THIS_FILE = /\A#{Regexp.quote(__FILE__)}:/o
+ CALLER_OFFSET = ((c = caller[0]) && THIS_FILE =~ c) ? 1 : 0
+ private_constant :THIS_FILE, :CALLER_OFFSET
+ # :startdoc:
-end
+ # Perform an operation in a block, raising an error if it takes longer than
+ # +sec+ seconds to complete.
+ #
+ # +sec+:: Number of seconds to wait for the block to terminate. Any number
+ # may be used, including Floats to specify fractional seconds. A
+ # value of 0 or +nil+ will execute the block without any timeout.
+ # +klass+:: Exception Class to raise if the block fails to terminate
+ # in +sec+ seconds. Omitting will use the default, Timeout::Error
+ # +message+:: Error message to raise with Exception Class.
+ # Omitting will use the default, "execution expired"
+ #
+ # Returns the result of the block *if* the block completed before
+ # +sec+ seconds, otherwise throws an exception, based on the value of +klass+.
+ #
+ # The exception thrown to terminate the given block cannot be rescued inside
+ # the block unless +klass+ is given explicitly. However, the block can use
+ # ensure to prevent the handling of the exception. For that reason, this
+ # method cannot be relied on to enforce timeouts for untrusted blocks.
+ #
+ # If a scheduler is defined, it will be used to handle the timeout by invoking
+ # Scheduler#timeout_after.
+ #
+ # Note that this is both a method of module Timeout, so you can <tt>include
+ # Timeout</tt> into your classes so they have a #timeout method, as well as
+ # a module method, so you can call it directly as Timeout.timeout().
+ def timeout(sec, klass = nil, message = nil, &block) #:yield: +sec+
+ return yield(sec) if sec == nil or sec.zero?
-##
-# Identical to:
-#
-# Timeout::timeout(n, e, &block).
-#
-# Defined for backwards compatibility with earlier versions of timeout.rb, see
-# Timeout#timeout.
+ message ||= "execution expired".freeze
-def timeout(n, e=Timeout::Error, &block) # :nodoc:
- Timeout::timeout(n, e, &block)
-end
-
-##
-# Another name for Timeout::Error, defined for backwards compatibility with
-# earlier versions of timeout.rb.
+ if Fiber.respond_to?(:current_scheduler) && (scheduler = Fiber.current_scheduler)&.respond_to?(:timeout_after)
+ return scheduler.timeout_after(sec, klass || Error, message, &block)
+ end
-TimeoutError = Timeout::Error # :nodoc:
+ from = "from #{caller_locations(1, 1)[0]}" if $DEBUG
+ e = Error
+ bl = proc do |exception|
+ begin
+ x = Thread.current
+ y = Thread.start {
+ Thread.current.name = from
+ begin
+ sleep sec
+ rescue => e
+ x.raise e
+ else
+ x.raise exception, message
+ end
+ }
+ return yield(sec)
+ ensure
+ if y
+ y.kill
+ y.join # make sure y is dead.
+ end
+ end
+ end
+ if klass
+ begin
+ bl.call(klass)
+ rescue klass => e
+ message = e.message
+ bt = e.backtrace
+ end
+ else
+ bt = Error.catch(message, &bl)
+ end
+ level = -caller(CALLER_OFFSET).size-2
+ while THIS_FILE =~ bt[level]
+ bt.delete_at(level)
+ end
+ raise(e, message, bt)
+ end
-if __FILE__ == $0
- p timeout(5) {
- 45
- }
- p timeout(5, TimeoutError) {
- 45
- }
- p timeout(nil) {
- 54
- }
- p timeout(0) {
- 54
- }
- p timeout(5) {
- loop {
- p 10
- sleep 1
- }
- }
+ module_function :timeout
end
-