51 lines
1.6 KiB
Go
51 lines
1.6 KiB
Go
// Copyright 2023 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package event
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// JoinSubscriptions joins multiple subscriptions to be able to track them as
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// one entity and collectively cancel them or consume any errors from them.
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func JoinSubscriptions(subs ...Subscription) Subscription {
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return NewSubscription(func(unsubbed <-chan struct{}) error {
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// Unsubscribe all subscriptions before returning
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defer func() {
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for _, sub := range subs {
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sub.Unsubscribe()
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}
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}()
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// Wait for an error on any of the subscriptions and propagate up
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errc := make(chan error, len(subs))
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for i := range subs {
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go func(sub Subscription) {
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select {
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case err := <-sub.Err():
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if err != nil {
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errc <- err
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}
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case <-unsubbed:
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}
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}(subs[i])
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}
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select {
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case err := <-errc:
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return err
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case <-unsubbed:
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return nil
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}
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})
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}
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