1 files changed, 18 insertions, 18 deletions

diff --git a/db/skiplist.h b/db/skiplist.h
index 8bd7776..b806ce0 100644
--- a/db/skiplist.h
+++ b/db/skiplist.h
@@ -123,9 +123,9 @@ class SkipList {
   bool KeyIsAfterNode(const Key& key, Node* n) const;
 
   // Return the earliest node that comes at or after key.
-  // Return NULL if there is no such node.
+  // Return nullptr if there is no such node.
   //
-  // If prev is non-NULL, fills prev[level] with pointer to previous
+  // If prev is non-null, fills prev[level] with pointer to previous
   // node at "level" for every level in [0..max_height_-1].
   Node* FindGreaterOrEqual(const Key& key, Node** prev) const;
 
@@ -190,12 +190,12 @@ SkipList<Key,Comparator>::NewNode(const Key& key, int height) {
 template<typename Key, class Comparator>
 inline SkipList<Key,Comparator>::Iterator::Iterator(const SkipList* list) {
   list_ = list;
-  node_ = NULL;
+  node_ = nullptr;
 }
 
 template<typename Key, class Comparator>
 inline bool SkipList<Key,Comparator>::Iterator::Valid() const {
-  return node_ != NULL;
+  return node_ != nullptr;
 }
 
 template<typename Key, class Comparator>
@@ -217,13 +217,13 @@ inline void SkipList<Key,Comparator>::Iterator::Prev() {
   assert(Valid());
   node_ = list_->FindLessThan(node_->key);
   if (node_ == list_->head_) {
-    node_ = NULL;
+    node_ = nullptr;
   }
 }
 
 template<typename Key, class Comparator>
 inline void SkipList<Key,Comparator>::Iterator::Seek(const Key& target) {
-  node_ = list_->FindGreaterOrEqual(target, NULL);
+  node_ = list_->FindGreaterOrEqual(target, nullptr);
 }
 
 template<typename Key, class Comparator>
@@ -235,7 +235,7 @@ template<typename Key, class Comparator>
 inline void SkipList<Key,Comparator>::Iterator::SeekToLast() {
   node_ = list_->FindLast();
   if (node_ == list_->head_) {
-    node_ = NULL;
+    node_ = nullptr;
   }
 }
 
@@ -254,8 +254,8 @@ int SkipList<Key,Comparator>::RandomHeight() {
 
 template<typename Key, class Comparator>
 bool SkipList<Key,Comparator>::KeyIsAfterNode(const Key& key, Node* n) const {
-  // NULL n is considered infinite
-  return (n != NULL) && (compare_(n->key, key) < 0);
+  // null n is considered infinite
+  return (n != nullptr) && (compare_(n->key, key) < 0);
 }
 
 template<typename Key, class Comparator>
@@ -269,7 +269,7 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
       // Keep searching in this list
       x = next;
     } else {
-      if (prev != NULL) prev[level] = x;
+      if (prev != nullptr) prev[level] = x;
       if (level == 0) {
         return next;
       } else {
@@ -288,7 +288,7 @@ SkipList<Key,Comparator>::FindLessThan(const Key& key) const {
   while (true) {
     assert(x == head_ || compare_(x->key, key) < 0);
     Node* next = x->Next(level);
-    if (next == NULL || compare_(next->key, key) >= 0) {
+    if (next == nullptr || compare_(next->key, key) >= 0) {
       if (level == 0) {
         return x;
       } else {
@@ -308,7 +308,7 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindLast()
   int level = GetMaxHeight() - 1;
   while (true) {
     Node* next = x->Next(level);
-    if (next == NULL) {
+    if (next == nullptr) {
       if (level == 0) {
         return x;
       } else {
@@ -329,7 +329,7 @@ SkipList<Key,Comparator>::SkipList(Comparator cmp, Arena* arena)
       max_height_(reinterpret_cast<void*>(1)),
       rnd_(0xdeadbeef) {
   for (int i = 0; i < kMaxHeight; i++) {
-    head_->SetNext(i, NULL);
+    head_->SetNext(i, nullptr);
   }
 }
 
@@ -341,7 +341,7 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
   Node* x = FindGreaterOrEqual(key, prev);
 
   // Our data structure does not allow duplicate insertion
-  assert(x == NULL || !Equal(key, x->key));
+  assert(x == nullptr || !Equal(key, x->key));
 
   int height = RandomHeight();
   if (height > GetMaxHeight()) {
@@ -353,9 +353,9 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
     // It is ok to mutate max_height_ without any synchronization
     // with concurrent readers.  A concurrent reader that observes
     // the new value of max_height_ will see either the old value of
-    // new level pointers from head_ (NULL), or a new value set in
+    // new level pointers from head_ (nullptr), or a new value set in
     // the loop below.  In the former case the reader will
-    // immediately drop to the next level since NULL sorts after all
+    // immediately drop to the next level since nullptr sorts after all
     // keys.  In the latter case the reader will use the new node.
     max_height_.NoBarrier_Store(reinterpret_cast<void*>(height));
   }
@@ -371,8 +371,8 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
 
 template<typename Key, class Comparator>
 bool SkipList<Key,Comparator>::Contains(const Key& key) const {
-  Node* x = FindGreaterOrEqual(key, NULL);
-  if (x != NULL && Equal(key, x->key)) {
+  Node* x = FindGreaterOrEqual(key, nullptr);
+  if (x != nullptr && Equal(key, x->key)) {
     return true;
   } else {
     return false;