worker.go

/*
 * Copyright (c) 2023 ivfzhou
 * goroutine-pool is licensed under Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 *          http://license.coscl.org.cn/MulanPSL2
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PSL v2 for more details.
 */

package goroutine_pool

import (
	"log"
	"runtime"
	"sync/atomic"
	"time"
)

var channelLength = func() int {
	if runtime.GOMAXPROCS(0) == 1 {
		return 0
	}
	return 1
}()

type worker struct {
	startIdleTime time.Time
	running       atomic.Uint32
	channel       chan func()
}

func newWorker() *worker {
	return &worker{startIdleTime: time.Now().Add(defaultIdleTimeout), channel: make(chan func(), channelLength)}
}

func wrapperPanic(f func()) func() {
	return func() {
		defer func() {
			if p := recover(); p != nil {
				log.Printf("panic: %v", p)
			}
		}()
		f()
	}
}

func (w *worker) start() {
	go func() {
		for fn := range w.channel {
			w.running.Store(1)
			wrapperPanic(fn)()
			w.startIdleTime = time.Now()
			w.running.Store(0)
		}
	}()
}

func (w *worker) isIdle(idleTimeout time.Duration) bool {
	if w.running.Load() <= 0 && time.Now().After(w.startIdleTime.Add(idleTimeout)) {
		return true
	}
	return false
}

func (w *worker) close() {
	close(w.channel)
}