Add log date to the metrics log

components/metrics/persisted_logs.h

 // Copyright 2014 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 COMPONENTS_METRICS_PERSISTED_LOGS_H_
 #define COMPONENTS_METRICS_PERSISTED_LOGS_H_
 
 #include <stddef.h>
 
 #include <string>
@@ skipping 54 matching lines @@
   // Adds a log to the list.
   void StoreLog(const std::string& log_data);
 
   // Stages the most recent log.  The staged_log will remain the same even if
   // additional logs are added.
   void StageLog();
 
   // Remove the staged log.
   void DiscardStagedLog();
 
+  void MigrateFromOldFormat(const char* old_pref_name);
+
   // True if a log has been staged.
   bool has_staged_log() const { return staged_log_index_ != -1; }
 
   // Returns the element in the front of the list.
   const std::string& staged_log() const {
     DCHECK(has_staged_log());
     return list_[staged_log_index_].compressed_log_data;
   }
 
   // Returns the element in the front of the list.
   const std::string& staged_log_hash() const {
     DCHECK(has_staged_log());
     return list_[staged_log_index_].hash;
   }
 
+  // Returns the timestamp of the element in the front of the list.
+  int staged_log_timestamp() const {
+    DCHECK(has_staged_log());
+    return list_[staged_log_index_].timestamp;
+  }
+
   // The number of elements currently stored.
   size_t size() const { return list_.size(); }
 
   // True if there are no stored logs.
   bool empty() const { return list_.empty(); }
 
  private:
   // Writes the list to the ListValue.
   void WriteLogsToPrefList(base::ListValue* list) const;
 
   // Reads the list from the ListValue.
   LogReadStatus ReadLogsFromPrefList(const base::ListValue& list);
 
+  // Reads the list from the ListValue in the old Log-hash pair format.
+  LogReadStatus ReadLogsFromPrefList_OldFormat(const base::ListValue& list);
+
   // A weak pointer to the PrefService object to read and write the preference
   // from.  Calling code should ensure this object continues to exist for the
   // lifetime of the PersistedLogs object.
   PrefService* local_state_;
 
   // The name of the preference to serialize logs to/from.
   const char* pref_name_;
 
   // We will keep at least this |min_log_count_| logs or |min_log_bytes_| bytes
   // of logs, whichever is greater, when writing to disk.  These apply after
   // skipping logs greater than |max_log_size_|.
   const size_t min_log_count_;
   const size_t min_log_bytes_;
 
   // Logs greater than this size will not be written to disk.
   const size_t max_log_size_;
 
-  struct LogHashPair {
+  struct LogInfo {
     // Initializes the members based on uncompressed |log_data|.
     void Init(const std::string& log_data);
 
     // Compressed log data - a serialized protobuf that's been gzipped.
     std::string compressed_log_data;
 
     // The SHA1 hash of log, stored to catch errors from memory corruption.
     std::string hash;
+
+    // The timestamp of when the log was created in seconds. Seconds is enough
+    // as decision for removing old logs wouldn't need more granularity.
+    int timestamp;

[Alexei Svitkine (slow), 2016/09/28 18:50:30]

Add a ctor so that this value is initialized.

[gayane -on leave until 09-2017, 2016/09/28 20:50:50]

Done.

   };
   // A list of all of the stored logs, stored with SHA1 hashes to check for
   // corruption while they are stored in memory.
-  std::vector<LogHashPair> list_;
+  std::vector<LogInfo> list_;
 
   // The index and type of the log staged for upload. If nothing has been
   // staged, the index will be -1.
   int staged_log_index_;
 
   DISALLOW_COPY_AND_ASSIGN(PersistedLogs);
 };
 
 }  // namespace metrics
 
 #endif  // COMPONENTS_METRICS_PERSISTED_LOGS_H_