Files
netris-cdc-file-transfer/common/thread_safe_map.h
Christian Schneider 4326e972ac Releasing the former Stadia file transfer tools
The tools allow efficient and fast synchronization of large directory
trees from a Windows workstation to a Linux target machine.

cdc_rsync* support efficient copy of files by using content-defined
chunking (CDC) to identify chunks within files that can be reused.

asset_stream_manager + cdc_fuse_fs support efficient streaming of a
local directory to a remote virtual file system based on FUSE. It also
employs CDC to identify and reuse unchanged data chunks.
2022-11-03 10:39:10 +01:00

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1.6 KiB
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/*
* Copyright 2022 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef COMMON_THREAD_SAFE_MAP_H_
#define COMMON_THREAD_SAFE_MAP_H_
#include <unordered_map>
#include "absl/synchronization/mutex.h"
namespace cdc_ft {
// A map with keys of type |key_type| and values of type |mapped_type|.
template <class key_type, class mapped_type>
class ThreadSafeMap {
public:
// Returns a value by the |key|. If the |key| is not present,
// returns a default value of the `mapped_type`.
mapped_type Get(const key_type& key) const ABSL_LOCKS_EXCLUDED(mutex_) {
absl::ReaderMutexLock lock(&mutex_);
auto it = kv_.find(key);
return it == kv_.end() ? mapped_type() : it->second;
}
// Sets |value| to |key|.
void Set(const key_type& key, const mapped_type& value)
ABSL_LOCKS_EXCLUDED(mutex_) {
absl::WriterMutexLock lock(&mutex_);
kv_[key] = value;
}
private:
mutable absl::Mutex mutex_;
std::unordered_map<key_type, mapped_type> kv_ ABSL_GUARDED_BY(mutex_);
};
} // namespace cdc_ft
#endif // COMMON_THREAD_SAFE_MAP_H_