| // Copyright 2013 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CHROME_BROWSER_CHROMEOS_POLICY_CLOUD_EXTERNAL_DATA_STORE_H_ |
| #define CHROME_BROWSER_CHROMEOS_POLICY_CLOUD_EXTERNAL_DATA_STORE_H_ |
| |
| #include <stddef.h> |
| |
| #include <string> |
| |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "components/policy/core/common/cloud/cloud_external_data_manager.h" |
| |
| namespace base { |
| class SequencedTaskRunner; |
| } |
| |
| namespace policy { |
| |
| class ResourceCache; |
| |
| // Stores external data referenced by policies. Data is keyed by (policy, hash), |
| // the name of the policy referencing it and its SHA1 hash. Outdated entries are |
| // removed by calling Prune() with the list of (policy, hash) entries that are |
| // to be kept. Instances of this class may be created on any thread and may |
| // share the same cache, however: |
| // * After creation, the cache and all stores using it must always be accessed |
| // via the same |task_runner| only. |
| // * Stores sharing a cache must use different cache_keys to avoid namespace |
| // overlaps. |
| // * The cache must outlive all stores using it. |
| class CloudExternalDataStore { |
| public: |
| CloudExternalDataStore(const std::string& cache_key, |
| scoped_refptr<base::SequencedTaskRunner> task_runner, |
| ResourceCache* cache); |
| ~CloudExternalDataStore(); |
| |
| // Removes all entries from the store whose (policy, hash) pair is not found |
| // in |metadata|. |
| void Prune(const CloudExternalDataManager::Metadata& metadata); |
| |
| // Stores |data| under (policy, hash). Returns true if the store succeeded. |
| bool Store(const std::string& policy, |
| const std::string& hash, |
| const std::string& data); |
| |
| // Loads the entry at (policy, hash) into |data|, verifies that it does not |
| // exceed |max_size| and matches the expected |hash|, then returns true. |
| // Returns false if no entry is found at (policy, hash), there is a problem |
| // during the load, the entry exceeds |max_size| or does not match |hash|. |
| bool Load(const std::string& policy, |
| const std::string& hash, |
| size_t max_size, |
| std::string* data); |
| |
| private: |
| std::string cache_key_; |
| |
| // Task runner that |this| runs on. |
| scoped_refptr<base::SequencedTaskRunner> task_runner_; |
| |
| ResourceCache* cache_; // Not owned. |
| |
| DISALLOW_COPY_AND_ASSIGN(CloudExternalDataStore); |
| }; |
| |
| } // namespace policy |
| |
| #endif // CHROME_BROWSER_CHROMEOS_POLICY_CLOUD_EXTERNAL_DATA_STORE_H_ |