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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
require 'thread'
require 'atomic/direct_update'
# Portable/generic (but not very memory or scheduling-efficient) fallback
class Atomic #:nodoc: all
def initialize(value = nil)
@mutex = Mutex.new
@value = value
end
def get
@mutex.synchronize { @value }
end
alias value get
def set(new_value)
@mutex.synchronize { @value = new_value }
end
alias value= set
def get_and_set(new_value)
@mutex.synchronize do
old_value = @value
@value = new_value
old_value
end
end
alias swap get_and_set
def compare_and_set(old_value, new_value)
return false unless @mutex.try_lock
begin
return false unless @value.equal? old_value
@value = new_value
ensure
@mutex.unlock
end
true
end
require 'atomic/numeric_cas_wrapper'
end
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