Fix naming in InternalKey

Summary:
- Switched all instances of SetMinPossibleForUserKey and SetMaxPossibleForUserKey in accordance to InternalKeyComparator's comparison logic
Closes https://github.com/facebook/rocksdb/pull/2868

Differential Revision: D5804152

Pulled By: axxufb

fbshipit-source-id: 80be35e04f2e8abc35cc64abe1fecb03af24e183

db/db_impl.cc

@@ -2055,13 +2055,13 @@ Status DBImpl::DeleteFilesInRange(ColumnFamilyHandle* column_family,
       if (begin == nullptr) {
         begin_key = nullptr;
       } else {
-        begin_storage.SetMaxPossibleForUserKey(*begin);
+        begin_storage.SetMinPossibleForUserKey(*begin);
         begin_key = &begin_storage;
       }
       if (end == nullptr) {
         end_key = nullptr;
       } else {
-        end_storage.SetMinPossibleForUserKey(*end);
+        end_storage.SetMaxPossibleForUserKey(*end);
         end_key = &end_storage;
       }
 

db/db_impl_compaction_flush.cc

@@ -826,7 +826,7 @@ Status DBImpl::RunManualCompaction(ColumnFamilyData* cfd, int input_level,
       cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
     manual.begin = nullptr;
   } else {
-    begin_storage.SetMaxPossibleForUserKey(*begin);
+    begin_storage.SetMinPossibleForUserKey(*begin);
     manual.begin = &begin_storage;
   }
   if (end == nullptr ||
@@ -834,7 +834,7 @@ Status DBImpl::RunManualCompaction(ColumnFamilyData* cfd, int input_level,
       cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
     manual.end = nullptr;
   } else {
-    end_storage.SetMinPossibleForUserKey(*end);
+    end_storage.SetMaxPossibleForUserKey(*end);
     manual.end = &end_storage;
   }
 

db/db_impl_experimental.cc

@@ -30,10 +30,10 @@ Status DBImpl::SuggestCompactRange(ColumnFamilyHandle* column_family,
   auto cfd = cfh->cfd();
   InternalKey start_key, end_key;
   if (begin != nullptr) {
-    start_key.SetMaxPossibleForUserKey(*begin);
+    start_key.SetMinPossibleForUserKey(*begin);
   }
   if (end != nullptr) {
-    end_key.SetMinPossibleForUserKey(*end);
+    end_key.SetMaxPossibleForUserKey(*end);
   }
   {
     InstrumentedMutexLock l(&mutex_);

db/dbformat.h

@@ -181,15 +181,15 @@ class InternalKey {
   // sets the internal key to be bigger or equal to all internal keys with this
   // user key
   void SetMaxPossibleForUserKey(const Slice& _user_key) {
-    AppendInternalKey(&rep_, ParsedInternalKey(_user_key, kMaxSequenceNumber,
-                                               kValueTypeForSeek));
+    AppendInternalKey(
+        &rep_, ParsedInternalKey(_user_key, 0, static_cast<ValueType>(0)));
   }
 
   // sets the internal key to be smaller or equal to all internal keys with this
   // user key
   void SetMinPossibleForUserKey(const Slice& _user_key) {
-    AppendInternalKey(
-        &rep_, ParsedInternalKey(_user_key, 0, static_cast<ValueType>(0)));
+    AppendInternalKey(&rep_, ParsedInternalKey(_user_key, kMaxSequenceNumber,
+                                               kValueTypeForSeek));
   }
 
   bool Valid() const {

db/version_set.cc

@@ -408,9 +408,9 @@ bool SomeFileOverlapsRange(
   // Binary search over file list
   uint32_t index = 0;
   if (smallest_user_key != nullptr) {
-    // Find the earliest possible internal key for smallest_user_key
+    // Find the leftmost possible internal key for smallest_user_key
     InternalKey small;
-    small.SetMaxPossibleForUserKey(*smallest_user_key);
+    small.SetMinPossibleForUserKey(*smallest_user_key);
     index = FindFile(icmp, file_level, small.Encode());
   }
 

tools/sst_dump_tool.cc

@@ -296,7 +296,7 @@ Status SstFileReader::ReadSequential(bool print_kv, uint64_t read_num,
   uint64_t i = 0;
   if (has_from) {
     InternalKey ikey;
-    ikey.SetMaxPossibleForUserKey(from_key);
+    ikey.SetMinPossibleForUserKey(from_key);
     iter->Seek(ikey.Encode());
   } else {
     iter->SeekToFirst();

utilities/debug.cc

@@ -24,7 +24,7 @@ Status GetAllKeyVersions(DB* db, Slice begin_key, Slice end_key,
 
   if (!begin_key.empty()) {
     InternalKey ikey;
-    ikey.SetMaxPossibleForUserKey(begin_key);
+    ikey.SetMinPossibleForUserKey(begin_key);
     iter->Seek(ikey.Encode());
   } else {
     iter->SeekToFirst();