31 lines
1.1 KiB
C
31 lines
1.1 KiB
C
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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#pragma once
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#include "rocksdb/status.h"
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namespace rocksdb {
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class DB;
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class PreReleaseCallback {
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public:
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virtual ~PreReleaseCallback() {}
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// Will be called while on the write thread after the write and before the
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// release of the sequence number. This is useful if any operation needs to be
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// done before the write gets visible to the readers, or if we want to reduce
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// the overhead of locking by updating something sequentially while we are on
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// the write thread. If the callback fails, this function returns a non-OK
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// status, the sequence number will not be released, and same status will be
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// propagated to all the writers in the write group.
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// seq is the sequence number that is used for this write and will be
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// released.
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virtual Status Callback(SequenceNumber seq) = 0;
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};
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} // namespace rocksdb
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