37 lines
830 B
Go
37 lines
830 B
Go
package workgroup
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import "sync"
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// Group manages a set of goroutines with related lifetimes.
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type Group struct {
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fn []func(<-chan struct{})
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}
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// Add adds a function to the Group. Must be called before Run.
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func (g *Group) Add(fn func(<-chan struct{})) {
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g.fn = append(g.fn, fn)
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}
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// Run exectues each function registered with Add in its own goroutine.
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// Run blocks until each function has returned.
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// The first function to return will trigger the closure of the channel
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// passed to each function, who should in turn, return.
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func (g *Group) Run() {
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var wg sync.WaitGroup
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wg.Add(len(g.fn))
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stop := make(chan struct{})
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result := make(chan error, len(g.fn))
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for _, fn := range g.fn {
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go func(fn func(<-chan struct{})) {
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defer wg.Done()
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fn(stop)
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result <- nil
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}(fn)
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}
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<-result
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close(stop)
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wg.Wait()
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}
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