IndexedDB: Switch key/value handling from vector<char> to std::string

content/browser/indexed_db/leveldb/leveldb_transaction.cc

Index: content/browser/indexed_db/leveldb/leveldb_transaction.cc
diff --git a/content/browser/indexed_db/leveldb/leveldb_transaction.cc b/content/browser/indexed_db/leveldb/leveldb_transaction.cc
index d8fc06138b8d726b1a7b08ad071078bbc352c129..7d11730093916548a96f30dd24aa63be65e6ca91 100644
--- a/content/browser/indexed_db/leveldb/leveldb_transaction.cc
+++ b/content/browser/indexed_db/leveldb/leveldb_transaction.cc
@@ -4,14 +4,13 @@
 
 #include "content/browser/indexed_db/leveldb/leveldb_transaction.h"
 
-#include <string>
-
 #include "base/logging.h"
 #include "content/browser/indexed_db/leveldb/leveldb_database.h"
-#include "content/browser/indexed_db/leveldb/leveldb_slice.h"
 #include "content/browser/indexed_db/leveldb/leveldb_write_batch.h"
 #include "third_party/leveldatabase/src/include/leveldb/db.h"
 
+using base::StringPiece;
+
 namespace content {
 
 scoped_refptr<LevelDBTransaction> LevelDBTransaction::Create(
@@ -45,13 +44,8 @@ void LevelDBTransaction::ClearTree() {
 
 LevelDBTransaction::~LevelDBTransaction() { ClearTree(); }
 
-static void InitVector(const LevelDBSlice& slice, std::vector<char>* vector) {
-  vector->clear();
-  vector->insert(vector->end(), slice.begin(), slice.end());
-}
-
-void LevelDBTransaction::Set(const LevelDBSlice& key,
-                             std::vector<char>* value,
+void LevelDBTransaction::Set(const StringPiece& key,
+                             std::string* value,
                              bool deleted) {
   DCHECK(!finished_);
   bool new_node = false;
@@ -59,7 +53,7 @@ void LevelDBTransaction::Set(const LevelDBSlice& key,
 
   if (!node) {
     node = new AVLTreeNode;
-    InitVector(key, &node->key);
+    node->key = key.as_string();
     tree_.Insert(node);
     new_node = true;
   }
@@ -70,17 +64,16 @@ void LevelDBTransaction::Set(const LevelDBSlice& key,
     NotifyIteratorsOfTreeChange();
 }
 
-void LevelDBTransaction::Put(const LevelDBSlice& key,
-                             std::vector<char>* value) {
+void LevelDBTransaction::Put(const StringPiece& key, std::string* value) {
   Set(key, value, false);
 }
 
-void LevelDBTransaction::Remove(const LevelDBSlice& key) {
-  std::vector<char> empty;
+void LevelDBTransaction::Remove(const StringPiece& key) {
+  std::string empty;
   Set(key, &empty, true);
 }
 
-bool LevelDBTransaction::Get(const LevelDBSlice& key,
+bool LevelDBTransaction::Get(const StringPiece& key,
                              std::string* value,
                              bool* found) {
   *found = false;
@@ -120,9 +113,9 @@ bool LevelDBTransaction::Commit() {
   while (*iterator) {
     AVLTreeNode* node = *iterator;
     if (!node->deleted)
-      write_batch->Put(LevelDBSlice(node->key), LevelDBSlice(node->value));
+      write_batch->Put(node->key, node->value);
     else
-      write_batch->Remove(LevelDBSlice(node->key));
+      write_batch->Remove(node->key);
     ++iterator;
   }
 
@@ -157,7 +150,7 @@ void LevelDBTransaction::TreeIterator::SeekToLast() {
     key_ = (*iterator_)->key;
 }
 
-void LevelDBTransaction::TreeIterator::Seek(const LevelDBSlice& target) {
+void LevelDBTransaction::TreeIterator::Seek(const StringPiece& target) {
   iterator_.StartIter(tree_, target, TreeType::EQUAL);
   if (!IsValid())
     iterator_.StartIter(tree_, target, TreeType::GREATER);
@@ -170,9 +163,7 @@ void LevelDBTransaction::TreeIterator::Next() {
   DCHECK(IsValid());
   ++iterator_;
   if (IsValid()) {
-    DCHECK(transaction_->comparator_->Compare(LevelDBSlice((*iterator_)->key),
-                                              LevelDBSlice(key_)) >
-           0);
+    DCHECK_GE(transaction_->comparator_->Compare((*iterator_)->key, key_), 0);
     key_ = (*iterator_)->key;
   }
 }
@@ -181,22 +172,21 @@ void LevelDBTransaction::TreeIterator::Prev() {
   DCHECK(IsValid());
   --iterator_;
   if (IsValid()) {
-    DCHECK(tree_->abstractor().comparator_->Compare(
-               LevelDBSlice((*iterator_)->key), LevelDBSlice(key_)) <
-           0);
+    DCHECK_LT(tree_->abstractor().comparator_->Compare((*iterator_)->key, key_),
+              0);
     key_ = (*iterator_)->key;
   }
 }
 
-LevelDBSlice LevelDBTransaction::TreeIterator::Key() const {
+StringPiece LevelDBTransaction::TreeIterator::Key() const {
   DCHECK(IsValid());
-  return LevelDBSlice(key_);
+  return key_;
 }
 
-LevelDBSlice LevelDBTransaction::TreeIterator::Value() const {
+StringPiece LevelDBTransaction::TreeIterator::Value() const {
   DCHECK(IsValid());
   DCHECK(!IsDeleted());
-  return LevelDBSlice((*iterator_)->value);
+  return (*iterator_)->value;
 }
 
 bool LevelDBTransaction::TreeIterator::IsDeleted() const {
@@ -206,7 +196,7 @@ bool LevelDBTransaction::TreeIterator::IsDeleted() const {
 
 void LevelDBTransaction::TreeIterator::Reset() {
   DCHECK(IsValid());
-  iterator_.StartIter(tree_, LevelDBSlice(key_), TreeType::EQUAL);
+  iterator_.StartIter(tree_, key_, TreeType::EQUAL);
   DCHECK(IsValid());
 }
 
@@ -250,7 +240,7 @@ void LevelDBTransaction::TransactionIterator::SeekToLast() {
   SetCurrentIteratorToLargestKey();
 }
 
-void LevelDBTransaction::TransactionIterator::Seek(const LevelDBSlice& target) {
+void LevelDBTransaction::TransactionIterator::Seek(const StringPiece& target) {
   tree_iterator_->Seek(target);
   db_iterator_->Seek(target);
   direction_ = FORWARD;
@@ -322,14 +312,14 @@ void LevelDBTransaction::TransactionIterator::Prev() {
   SetCurrentIteratorToLargestKey();
 }
 
-LevelDBSlice LevelDBTransaction::TransactionIterator::Key() const {
+StringPiece LevelDBTransaction::TransactionIterator::Key() const {
   DCHECK(IsValid());
   if (tree_changed_)
     RefreshTreeIterator();
   return current_->Key();
 }
 
-LevelDBSlice LevelDBTransaction::TransactionIterator::Value() const {
+StringPiece LevelDBTransaction::TransactionIterator::Value() const {
   DCHECK(IsValid());
   if (tree_changed_)
     RefreshTreeIterator();
@@ -472,7 +462,7 @@ LevelDBWriteOnlyTransaction::~LevelDBWriteOnlyTransaction() {
   write_batch_->Clear();
 }
 
-void LevelDBWriteOnlyTransaction::Remove(const LevelDBSlice& key) {
+void LevelDBWriteOnlyTransaction::Remove(const StringPiece& key) {
   DCHECK(!finished_);
   write_batch_->Remove(key);
 }