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Viewing changes to worker/simpleworker.go

[r=axwalk],[bug=1308852] worker: fix simpleworker Kill

gccgo does not like it when you
close a channel twice. It's not
a very nice thing anyway.

Fixes lp:1308852

https://codereview.appspot.com/98480046/

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Lines of Context:
worker/simpleworker.go
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// by the doWork function will be returned by the worker's Wait function.
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func NewSimpleWorker(doWork func(stopCh <-chan struct{}) error) Worker {
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        w := &simpleWorker{
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                stopc: make(chan struct{}),
 
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                stopc: make(chan struct{}, 1),
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                done:  make(chan struct{}),
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        }
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        go func() {
 
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                defer close(w.done)
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                w.err = doWork(w.stopc)
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                close(w.done)
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        }()
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        return w
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}
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// Kill implements Worker.Kill() and will close the channel given to the doWork
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// function.
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func (w *simpleWorker) Kill() {
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        defer func() {
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                // Allow any number of calls to Kill - the second and subsequent calls
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                // will panic, but we don't care.
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                recover()
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        }()
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        close(w.stopc)
 
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        select {
 
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        case w.stopc <- struct{}{}:
 
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        default: // stopc is already closed
 
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        }
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}
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// Wait implements Worker.Wait(), and will return the error returned by