diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:54:28 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:54:28 +0000 |
commit | e6918187568dbd01842d8d1d2c808ce16a894239 (patch) | |
tree | 64f88b554b444a49f656b6c656111a145cbbaa28 /src/rocksdb/util/channel.h | |
parent | Initial commit. (diff) | |
download | ceph-e6918187568dbd01842d8d1d2c808ce16a894239.tar.xz ceph-e6918187568dbd01842d8d1d2c808ce16a894239.zip |
Adding upstream version 18.2.2.upstream/18.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/rocksdb/util/channel.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/src/rocksdb/util/channel.h b/src/rocksdb/util/channel.h new file mode 100644 index 000000000..19b956297 --- /dev/null +++ b/src/rocksdb/util/channel.h @@ -0,0 +1,69 @@ +// Copyright (c) 2011-present, Facebook, Inc. All rights reserved. +// This source code is licensed under both the GPLv2 (found in the +// COPYING file in the root directory) and Apache 2.0 License +// (found in the LICENSE.Apache file in the root directory). + +#pragma once + +#include <condition_variable> +#include <mutex> +#include <queue> +#include <utility> + +#include "rocksdb/rocksdb_namespace.h" + +namespace ROCKSDB_NAMESPACE { + +template <class T> +class channel { + public: + explicit channel() : eof_(false) {} + + channel(const channel&) = delete; + void operator=(const channel&) = delete; + + void sendEof() { + std::lock_guard<std::mutex> lk(lock_); + eof_ = true; + cv_.notify_all(); + } + + bool eof() { + std::lock_guard<std::mutex> lk(lock_); + return buffer_.empty() && eof_; + } + + size_t size() const { + std::lock_guard<std::mutex> lk(lock_); + return buffer_.size(); + } + + // writes elem to the queue + void write(T&& elem) { + std::unique_lock<std::mutex> lk(lock_); + buffer_.emplace(std::forward<T>(elem)); + cv_.notify_one(); + } + + /// Moves a dequeued element onto elem, blocking until an element + /// is available. + // returns false if EOF + bool read(T& elem) { + std::unique_lock<std::mutex> lk(lock_); + cv_.wait(lk, [&] { return eof_ || !buffer_.empty(); }); + if (eof_ && buffer_.empty()) { + return false; + } + elem = std::move(buffer_.front()); + buffer_.pop(); + cv_.notify_one(); + return true; + } + + private: + std::condition_variable cv_; + mutable std::mutex lock_; + std::queue<T> buffer_; + bool eof_; +}; +} // namespace ROCKSDB_NAMESPACE |