Use "nullptr" for null pointer values

PiperOrigin-RevId: 157468186

7 files changed, 42 insertions, 40 deletions

diff --git a/tensorflow/core/lib/io/block.cc b/tensorflow/core/lib/io/block.cc
index 30c842208f..1fa26d9147 100644
--- a/tensorflow/core/lib/io/block.cc
+++ b/tensorflow/core/lib/io/block.cc
@@ -64,7 +64,7 @@ Block::~Block() {
 static inline const char* DecodeEntry(const char* p, const char* limit,
                                       uint32* shared, uint32* non_shared,
                                       uint32* value_length) {
-  if (limit - p < 3) return NULL;
+  if (limit - p < 3) return nullptr;
   *shared = reinterpret_cast<const unsigned char*>(p)[0];
   *non_shared = reinterpret_cast<const unsigned char*>(p)[1];
   *value_length = reinterpret_cast<const unsigned char*>(p)[2];
@@ -72,13 +72,15 @@ static inline const char* DecodeEntry(const char* p, const char* limit,
     // Fast path: all three values are encoded in one byte each
     p += 3;
   } else {
-    if ((p = core::GetVarint32Ptr(p, limit, shared)) == NULL) return NULL;
-    if ((p = core::GetVarint32Ptr(p, limit, non_shared)) == NULL) return NULL;
-    if ((p = core::GetVarint32Ptr(p, limit, value_length)) == NULL) return NULL;
+    if ((p = core::GetVarint32Ptr(p, limit, shared)) == nullptr) return nullptr;
+    if ((p = core::GetVarint32Ptr(p, limit, non_shared)) == nullptr)
+      return nullptr;
+    if ((p = core::GetVarint32Ptr(p, limit, value_length)) == nullptr)
+      return nullptr;
   }
 
   if (static_cast<uint32>(limit - p) < (*non_shared + *value_length)) {
-    return NULL;
+    return nullptr;
   }
   return p;
 }
@@ -158,7 +160,7 @@ class Block::Iter : public Iterator {
       const char* key_ptr =
           DecodeEntry(data_ + region_offset, data_ + restarts_, &shared,
                       &non_shared, &value_length);
-      if (key_ptr == NULL || (shared != 0)) {
+      if (key_ptr == nullptr || (shared != 0)) {
         CorruptionError();
         return;
       }
@@ -214,7 +216,7 @@ class Block::Iter : public Iterator {
     // Decode next entry
     uint32 shared, non_shared, value_length;
     p = DecodeEntry(p, limit, &shared, &non_shared, &value_length);
-    if (p == NULL || key_.size() < shared) {
+    if (p == nullptr || key_.size() < shared) {
       CorruptionError();
       return false;
     } else {
diff --git a/tensorflow/core/lib/io/iterator.cc b/tensorflow/core/lib/io/iterator.cc
index 95d2da402b..60f9981c2f 100644
--- a/tensorflow/core/lib/io/iterator.cc
+++ b/tensorflow/core/lib/io/iterator.cc
@@ -19,14 +19,14 @@ namespace tensorflow {
 namespace table {
 
 Iterator::Iterator() {
-  cleanup_.function = NULL;
-  cleanup_.next = NULL;
+  cleanup_.function = nullptr;
+  cleanup_.next = nullptr;
 }
 
 Iterator::~Iterator() {
-  if (cleanup_.function != NULL) {
+  if (cleanup_.function != nullptr) {
     (*cleanup_.function)(cleanup_.arg1, cleanup_.arg2);
-    for (Cleanup* c = cleanup_.next; c != NULL;) {
+    for (Cleanup* c = cleanup_.next; c != nullptr;) {
       (*c->function)(c->arg1, c->arg2);
       Cleanup* next = c->next;
       delete c;
@@ -36,9 +36,9 @@ Iterator::~Iterator() {
 }
 
 void Iterator::RegisterCleanup(CleanupFunction func, void* arg1, void* arg2) {
-  assert(func != NULL);
+  assert(func != nullptr);
   Cleanup* c;
-  if (cleanup_.function == NULL) {
+  if (cleanup_.function == nullptr) {
     c = &cleanup_;
   } else {
     c = new Cleanup;
diff --git a/tensorflow/core/lib/io/table.cc b/tensorflow/core/lib/io/table.cc
index 41eb38fe19..1ef7bb6ccd 100644
--- a/tensorflow/core/lib/io/table.cc
+++ b/tensorflow/core/lib/io/table.cc
@@ -40,7 +40,7 @@ struct Table::Rep {
 
 Status Table::Open(const Options& options, RandomAccessFile* file, uint64 size,
                    Table** table) {
-  *table = NULL;
+  *table = nullptr;
   if (size < Footer::kEncodedLength) {
     return errors::DataLoss("file is too short to be an sstable");
   }
@@ -57,7 +57,7 @@ Status Table::Open(const Options& options, RandomAccessFile* file, uint64 size,
 
   // Read the index block
   BlockContents contents;
-  Block* index_block = NULL;
+  Block* index_block = nullptr;
   if (s.ok()) {
     s = ReadBlock(file, footer.index_handle(), &contents);
     if (s.ok()) {
@@ -94,7 +94,7 @@ static void DeleteBlock(void* arg, void* ignored) {
 Iterator* Table::BlockReader(void* arg, const StringPiece& index_value) {
   Table* table = reinterpret_cast<Table*>(arg);
   //  Cache* block_cache = table->rep_->options.block_cache;
-  Block* block = NULL;
+  Block* block = nullptr;
   //  Cache::Handle* cache_handle = NULL;
 
   BlockHandle handle;
@@ -112,9 +112,9 @@ Iterator* Table::BlockReader(void* arg, const StringPiece& index_value) {
   }
 
   Iterator* iter;
-  if (block != NULL) {
+  if (block != nullptr) {
     iter = block->NewIterator();
-    iter->RegisterCleanup(&DeleteBlock, block, NULL);
+    iter->RegisterCleanup(&DeleteBlock, block, nullptr);
   } else {
     iter = NewErrorIterator(s);
   }
diff --git a/tensorflow/core/lib/io/table_test.cc b/tensorflow/core/lib/io/table_test.cc
index d2002d69c4..d479c2d533 100644
--- a/tensorflow/core/lib/io/table_test.cc
+++ b/tensorflow/core/lib/io/table_test.cc
@@ -177,11 +177,11 @@ class Constructor {
 
 class BlockConstructor : public Constructor {
  public:
-  BlockConstructor() : block_(NULL) {}
+  BlockConstructor() : block_(nullptr) {}
   ~BlockConstructor() override { delete block_; }
   Status FinishImpl(const Options& options, const KVMap& data) override {
     delete block_;
-    block_ = NULL;
+    block_ = nullptr;
     BlockBuilder builder(&options);
 
     for (KVMap::const_iterator it = data.begin(); it != data.end(); ++it) {
@@ -205,7 +205,7 @@ class BlockConstructor : public Constructor {
 
 class TableConstructor : public Constructor {
  public:
-  TableConstructor() : source_(NULL), table_(NULL) {}
+  TableConstructor() : source_(nullptr), table_(nullptr) {}
   ~TableConstructor() override { Reset(); }
   Status FinishImpl(const Options& options, const KVMap& data) override {
     Reset();
@@ -239,8 +239,8 @@ class TableConstructor : public Constructor {
   void Reset() {
     delete table_;
     delete source_;
-    table_ = NULL;
-    source_ = NULL;
+    table_ = nullptr;
+    source_ = nullptr;
   }
 
   StringSource* source_;
@@ -262,11 +262,11 @@ static const int kNumTestArgs = sizeof(kTestArgList) / sizeof(kTestArgList[0]);
 
 class Harness : public ::testing::Test {
  public:
-  Harness() : constructor_(NULL) {}
+  Harness() : constructor_(nullptr) {}
 
   void Init(const TestArgs& args) {
     delete constructor_;
-    constructor_ = NULL;
+    constructor_ = nullptr;
     options_ = Options();
 
     options_.block_restart_interval = args.restart_interval;
diff --git a/tensorflow/core/lib/io/two_level_iterator.cc b/tensorflow/core/lib/io/two_level_iterator.cc
index 8a1034ceea..ad66ae40d8 100644
--- a/tensorflow/core/lib/io/two_level_iterator.cc
+++ b/tensorflow/core/lib/io/two_level_iterator.cc
@@ -54,7 +54,7 @@ class TwoLevelIterator : public Iterator {
     // Status
     if (!index_iter_->status().ok()) {
       return index_iter_->status();
-    } else if (data_iter_ != NULL && !data_iter_->status().ok()) {
+    } else if (data_iter_ != nullptr && !data_iter_->status().ok()) {
       return data_iter_->status();
     } else {
       return status_;
@@ -84,7 +84,7 @@ TwoLevelIterator::TwoLevelIterator(Iterator* index_iter,
     : block_function_(block_function),
       arg_(arg),
       index_iter_(index_iter),
-      data_iter_(NULL) {}
+      data_iter_(nullptr) {}
 
 TwoLevelIterator::~TwoLevelIterator() {
   delete index_iter_;
@@ -94,14 +94,14 @@ TwoLevelIterator::~TwoLevelIterator() {
 void TwoLevelIterator::Seek(const StringPiece& target) {
   index_iter_->Seek(target);
   InitDataBlock();
-  if (data_iter_ != NULL) data_iter_->Seek(target);
+  if (data_iter_ != nullptr) data_iter_->Seek(target);
   SkipEmptyDataBlocksForward();
 }
 
 void TwoLevelIterator::SeekToFirst() {
   index_iter_->SeekToFirst();
   InitDataBlock();
-  if (data_iter_ != NULL) data_iter_->SeekToFirst();
+  if (data_iter_ != nullptr) data_iter_->SeekToFirst();
   SkipEmptyDataBlocksForward();
 }
 
@@ -112,20 +112,20 @@ void TwoLevelIterator::Next() {
 }
 
 void TwoLevelIterator::SkipEmptyDataBlocksForward() {
-  while (data_iter_ == NULL || !data_iter_->Valid()) {
+  while (data_iter_ == nullptr || !data_iter_->Valid()) {
     // Move to next block
     if (!index_iter_->Valid()) {
-      SetDataIterator(NULL);
+      SetDataIterator(nullptr);
       return;
     }
     index_iter_->Next();
     InitDataBlock();
-    if (data_iter_ != NULL) data_iter_->SeekToFirst();
+    if (data_iter_ != nullptr) data_iter_->SeekToFirst();
   }
 }
 
 void TwoLevelIterator::SetDataIterator(Iterator* data_iter) {
-  if (data_iter_ != NULL) {
+  if (data_iter_ != nullptr) {
     SaveError(data_iter_->status());
     delete data_iter_;
   }
@@ -134,10 +134,10 @@ void TwoLevelIterator::SetDataIterator(Iterator* data_iter) {
 
 void TwoLevelIterator::InitDataBlock() {
   if (!index_iter_->Valid()) {
-    SetDataIterator(NULL);
+    SetDataIterator(nullptr);
   } else {
     StringPiece handle = index_iter_->value();
-    if (data_iter_ != NULL && handle.compare(data_block_handle_) == 0) {
+    if (data_iter_ != nullptr && handle.compare(data_block_handle_) == 0) {
       // data_iter_ is already constructed with this iterator, so
       // no need to change anything
     } else {
diff --git a/tensorflow/core/lib/io/zlib_inputstream.cc b/tensorflow/core/lib/io/zlib_inputstream.cc
index 6b64011cc3..d019b65510 100644
--- a/tensorflow/core/lib/io/zlib_inputstream.cc
+++ b/tensorflow/core/lib/io/zlib_inputstream.cc
@@ -60,7 +60,7 @@ void ZlibInputStream::InitZlibBuffer() {
   int status = inflateInit2(z_stream_.get(), zlib_options_.window_bits);
   if (status != Z_OK) {
     LOG(FATAL) << "inflateInit failed with status " << status;
-    z_stream_.reset(NULL);
+    z_stream_.reset(nullptr);
   } else {
     z_stream_->next_in = z_stream_input_.get();
     z_stream_->next_out = z_stream_output_.get();
@@ -180,7 +180,7 @@ Status ZlibInputStream::Inflate() {
   if (error != Z_OK && error != Z_STREAM_END) {
     string error_string =
         strings::StrCat("inflate() failed with error ", error);
-    if (z_stream_->msg != NULL) {
+    if (z_stream_->msg != nullptr) {
       strings::StrAppend(&error_string, ": ", z_stream_->msg);
     }
     return errors::DataLoss(error_string);
diff --git a/tensorflow/core/lib/io/zlib_outputbuffer.cc b/tensorflow/core/lib/io/zlib_outputbuffer.cc
index a65b36b64d..5901504b87 100644
--- a/tensorflow/core/lib/io/zlib_outputbuffer.cc
+++ b/tensorflow/core/lib/io/zlib_outputbuffer.cc
@@ -58,7 +58,7 @@ Status ZlibOutputBuffer::Init() {
                    zlib_options_.compression_method, zlib_options_.window_bits,
                    zlib_options_.mem_level, zlib_options_.compression_strategy);
   if (status != Z_OK) {
-    z_stream_.reset(NULL);
+    z_stream_.reset(nullptr);
     return errors::InvalidArgument("deflateInit failed with status", status);
   }
   z_stream_->next_in = z_stream_input_.get();
@@ -206,7 +206,7 @@ Status ZlibOutputBuffer::Close() {
   TF_RETURN_IF_ERROR(DeflateBuffered(true));
   TF_RETURN_IF_ERROR(FlushOutputBufferToFile());
   deflateEnd(z_stream_.get());
-  z_stream_.reset(NULL);
+  z_stream_.reset(nullptr);
   return Status::OK();
 }
 
@@ -217,7 +217,7 @@ Status ZlibOutputBuffer::Deflate(int flush) {
     return Status::OK();
   }
   string error_string = strings::StrCat("deflate() failed with error ", error);
-  if (z_stream_->msg != NULL) {
+  if (z_stream_->msg != nullptr) {
     strings::StrAppend(&error_string, ": ", z_stream_->msg);
   }
   return errors::DataLoss(error_string);