fix FileReader bugs

* Reset() and SetFilePos() should flush old buffer
* make GetFilePos() work immediately after SetFilePos()
* refactor Reset() to use SetFilePos()
* refactor FindNewLine() to use GetFilePos()
* remove useless GetBufPos()

2 files changed, 6 insertions, 12 deletions

diff --git a/fbench/src/util/filereader.cpp b/fbench/src/util/filereader.cpp
index 30469e18e0c..b4c1c18a7d3 100644
--- a/fbench/src/util/filereader.cpp
+++ b/fbench/src/util/filereader.cpp
@@ -50,17 +50,15 @@ bool
 FileReader::Reset()
 {
     _file->clear();
-    _file->seekg(0);
-    _nextReadPos = 0;
-    return bool(*_file);
+    return SetFilePos(0);
 }
 
 bool
 FileReader::SetFilePos(int64_t pos)
 {
-    _bufpos = 0;
+    _bufused = _bufpos = 0;
+    _lastReadPos = _nextReadPos = pos;
     _file->seekg(pos);
-    _nextReadPos = pos;
     return bool(*_file);
 }
 
@@ -76,10 +74,8 @@ FileReader::FindNewline(int64_t pos)
 {
     char buf[100];
     SetFilePos(pos);
-    ssize_t len = ReadLine(buf, 100);
-    ++_bufpos;
-
-    return pos+len;
+    ReadLine(buf, 100);
+    return GetFilePos();
 }
 
 void
diff --git a/fbench/src/util/filereader.h b/fbench/src/util/filereader.h
index 6b85ad3ba51..a0ec794836a 100644
--- a/fbench/src/util/filereader.h
+++ b/fbench/src/util/filereader.h
@@ -96,10 +96,8 @@ public:
   int64_t GetFileSize();
 
   /**
-   * @returns _bufpos
+   * @return current position in file
    **/
-  uint64_t GetBufPos() const { return _bufpos; }
-
   uint64_t GetFilePos() const { return _lastReadPos + _bufpos; }
 
   /**