commit fa89589f207927628ccf5fad930c3a673a44f467
author Austin Schuh <austin.linux@gmail.com> Tue Jan 07 20:07:41 2020 -0800
committer Austin Schuh <austin.linux@gmail.com> Tue Jan 07 20:08:28 2020 -0800
tree cefd9fe53da314f39d32ddae8168c3c6130218fc
parent 6331ef95632274faccd5f00173d1c1169c8b48f1

Add support for rotated log files

We want to be able to chunk log files.  This adds read support for
chunking.  Write support is only added to enable testing, and needs more
configuration to be useful.

Change-Id: I0c7bc9980438a934ac0f2692ef06caf2605bbc88

aos/events/logging/logfile_utils.h

diff --git a/aos/events/logging/logfile_utils.h b/aos/events/logging/logfile_utils.h
index 285fe05..6b8e9aa 100644
--- a/aos/events/logging/logfile_utils.h
+++ b/aos/events/logging/logfile_utils.h
@@ -5,6 +5,7 @@
 
 #include <deque>
 #include <optional>
+#include <string>
 #include <string_view>
 #include <vector>
 
@@ -198,11 +199,11 @@
 // sorted list of pointers to those.
 class SortedMessageReader {
  public:
-  SortedMessageReader(std::string_view filename);
+  SortedMessageReader(const std::vector<std::string> &filenames);
 
   // Returns the header from the log file.
   const LogFileHeader *log_file_header() const {
-    return message_reader_.log_file_header();
+    return &log_file_header_.message();
   }
 
   // Returns a pointer to the channel with the oldest message in it, and the
@@ -250,6 +251,9 @@
   PopOldestChannel();
 
  private:
+  // Moves to the next log file in the list.
+  bool NextLogFile();
+
   // Adds more messages to the sorted list.
   void QueueMessages();
 
@@ -279,7 +283,11 @@
     }
   };
 
-  MessageReader message_reader_;
+  std::vector<std::string> filenames_;
+  size_t next_filename_index_ = 0;
+
+  FlatbufferDetachedBuffer<LogFileHeader> log_file_header_;
+  std::unique_ptr<MessageReader> message_reader_;
 
   // TODO(austin): Multithreaded read at some point.  Gotta go faster!
   // Especially if we start compressing.