Squashed 'src/leveldb/' changes from be1b0ff..936b461

936b461 Merge upstream LevelDB 1.13.
748539c LevelDB 1.13

git-subtree-dir: src/leveldb
git-subtree-split: 936b4613ea4551992e6096b1e05eeefc09a20e3b

db/version_set.h

@@ -78,6 +78,12 @@ class Version {
   // REQUIRES: lock is held
   bool UpdateStats(const GetStats& stats);
 
+  // Record a sample of bytes read at the specified internal key.
+  // Samples are taken approximately once every config::kReadBytesPeriod
+  // bytes.  Returns true if a new compaction may need to be triggered.
+  // REQUIRES: lock is held
+  bool RecordReadSample(Slice key);
+
   // Reference count management (so Versions do not disappear out from
   // under live iterators)
   void Ref();
@@ -114,6 +120,15 @@ class Version {
   class LevelFileNumIterator;
   Iterator* NewConcatenatingIterator(const ReadOptions&, int level) const;
 
+  // Call func(arg, level, f) for every file that overlaps user_key in
+  // order from newest to oldest.  If an invocation of func returns
+  // false, makes no more calls.
+  //
+  // REQUIRES: user portion of internal_key == user_key.
+  void ForEachOverlapping(Slice user_key, Slice internal_key,
+                          void* arg,
+                          bool (*func)(void*, int, FileMetaData*));
+
   VersionSet* vset_;            // VersionSet to which this Version belongs
   Version* next_;               // Next version in linked list
   Version* prev_;               // Previous version in linked list