49 lines
1.4 KiB
Go
49 lines
1.4 KiB
Go
// Copyright 2018 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 feed
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import (
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"bytes"
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"context"
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"time"
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"github.com/ethereum/go-ethereum/swarm/storage"
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)
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const (
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hasherCount = 8
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feedsHashAlgorithm = storage.SHA3Hash
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defaultRetrieveTimeout = 1000 * time.Millisecond
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)
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// cacheEntry caches the last known update of a specific Swarm feed.
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type cacheEntry struct {
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Update
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*bytes.Reader
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lastKey storage.Address
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}
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// implements storage.LazySectionReader
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func (r *cacheEntry) Size(ctx context.Context, _ chan bool) (int64, error) {
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return int64(len(r.Update.data)), nil
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}
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//returns the feed's topic
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func (r *cacheEntry) Topic() Topic {
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return r.Feed.Topic
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}
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