38 lines
696 B
Go
38 lines
696 B
Go
// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
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// Use of this source code is governed by an MIT license
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// that can be found in the LICENSE file.
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module sync
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struct WaitGroup {
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mut:
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mu Mutex
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finished Mutex
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active int
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}
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pub fn (wg mut WaitGroup) add(delta int) {
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wg.mu.lock()
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if wg.active == 0 {
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wg.finished.lock()
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}
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wg.active += delta
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if wg.active < 0 {
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panic('Negative number of jobs in waitgroup')
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}
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if wg.active == 0 {
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wg.finished.unlock()
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}
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wg.mu.unlock()
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}
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pub fn (wg mut WaitGroup) done() {
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wg.add(-1)
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}
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pub fn (wg mut WaitGroup) wait() {
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wg.finished.lock()
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wg.finished.unlock()
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}
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