Move rate_limiter, write buffering, most perf context instrumentation and most random kill out of Env

Summary: We want to keep Env a think layer for better portability. Less platform dependent codes should be moved out of Env. In this patch, I create a wrapper of file readers and writers, and put rate limiting, write buffering, as well as most perf context instrumentation and random kill out of Env. It will make it easier to maintain multiple Env in the future.

Test Plan: Run all existing unit tests.

Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D42321

1 files changed, 4 insertions, 4 deletions

diff --git a/db/log_reader.h b/db/log_reader.h
index e6cbf47ac..390696b85 100644
--- a/db/log_reader.h
+++ b/db/log_reader.h
@@ -17,7 +17,7 @@
 
 namespace rocksdb {
 
-class SequentialFile;
+class SequentialFileReader;
 using std::unique_ptr;
 
 namespace log {
@@ -51,7 +51,7 @@ class Reader {
   //
   // The Reader will start reading at the first record located at physical
   // position >= initial_offset within the file.
-  Reader(unique_ptr<SequentialFile>&& file, Reporter* reporter,
+  Reader(unique_ptr<SequentialFileReader>&& file, Reporter* reporter,
          bool checksum, uint64_t initial_offset);
 
   ~Reader();
@@ -81,10 +81,10 @@ class Reader {
   // block that was partially read.
   void UnmarkEOF();
 
-  SequentialFile* file() { return file_.get(); }
+  SequentialFileReader* file() { return file_.get(); }
 
  private:
-  const unique_ptr<SequentialFile> file_;
+  const unique_ptr<SequentialFileReader> file_;
   Reporter* const reporter_;
   bool const checksum_;
   char* const backing_store_;