60 lines
1.6 KiB
Go
60 lines
1.6 KiB
Go
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/*
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* MinIO Cloud Storage, (C) 2017 MinIO, Inc.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package errgroup
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import (
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"sync"
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)
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// A Group is a collection of goroutines working on subtasks that are part of
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// the same overall task.
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//
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// A zero Group is valid and does not cancel on error.
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type Group struct {
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wg sync.WaitGroup
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errs []error
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}
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// WithNErrs returns a new Group with length of errs slice upto nerrs,
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// upon Wait() errors are returned collected from all tasks.
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func WithNErrs(nerrs int) *Group {
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return &Group{errs: make([]error, nerrs)}
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}
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// Wait blocks until all function calls from the Go method have returned, then
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// returns the slice of errors from all function calls.
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func (g *Group) Wait() []error {
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g.wg.Wait()
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return g.errs
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}
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// Go calls the given function in a new goroutine.
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//
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// The first call to return a non-nil error will be
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// collected in errs slice and returned by Wait().
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func (g *Group) Go(f func() error, index int) {
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g.wg.Add(1)
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go func() {
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defer g.wg.Done()
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if err := f(); err != nil {
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g.errs[index] = err
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}
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}()
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}
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