Address code review comments both GH and internal

 Fix compilation issues on GCC/CLANG
 Address Windows Release test build issues due to Sync

db/db_iter_test.cc

@@ -1884,6 +1884,8 @@ TEST_F(DBIterWithMergeIterTest, InnerMergeIterator2) {
   ASSERT_EQ(db_iter_->value().ToString(), "4");
 }
 
+#if !(defined NDEBUG) || !defined(OS_WIN)
+
 TEST_F(DBIterWithMergeIterTest, InnerMergeIteratorDataRace1) {
   // Test Prev() when one child iterator is at its end but more rows
   // are added.
@@ -2234,6 +2236,7 @@ TEST_F(DBIterWithMergeIterTest, InnerMergeIteratorDataRace8) {
 
   rocksdb::SyncPoint::GetInstance()->DisableProcessing();
 }
+#endif // #if !(defined NDEBUG) || !defined(OS_WIN)
 }  // namespace rocksdb
 
 int main(int argc, char** argv) {

include/rocksdb/env.h

@@ -395,7 +395,7 @@ class RandomAccessFile {
 
   // Used by the file_reader_writer to decide if the ReadAhead wrapper
   // should simply forward the call and do not enact buffering or locking.
-  virtual bool ReaderWriterForward() const {
+  virtual bool ShouldForwardRawRequest() const {
     return false;
   }
 
@@ -448,18 +448,20 @@ class WritableFile {
     return true;
   }
 
+  const size_t c_DefaultPageSize = 4 * 1024;
+
   // This is needed when you want to allocate
   // AlignedBuffer for use with file I/O classes
   // Used for unbuffered file I/O when UseOSBuffer() returns false
   virtual size_t GetRequiredBufferAlignment() const {
-    return 4 * 1024;
+    return c_DefaultPageSize;
   }
 
   virtual Status Append(const Slice& data) = 0;
 
-  // Positional write for unbuffered access default forward
+  // Positioned write for unbuffered access default forward
   // to simple append as most of the tests are buffered by default
-  virtual Status Append(const Slice& /* data */, uint64_t /* offset */) {
+  virtual Status PositionedAppend(const Slice& /* data */, uint64_t /* offset */) {
     return Status::NotSupported();
   }
 
@@ -467,7 +469,9 @@ class WritableFile {
   // before closing. It is not always possible to keep track of the file
   // size due to whole pages writes. The behavior is undefined if called
   // with other writes to follow.
-  virtual Status Truncate(uint64_t size) = 0;
+  virtual Status Truncate(uint64_t size) {
+    return Status::OK();
+  }
   virtual Status Close() = 0;
   virtual Status Flush() = 0;
   virtual Status Sync() = 0; // sync data
@@ -868,6 +872,9 @@ class WritableFileWrapper : public WritableFile {
   explicit WritableFileWrapper(WritableFile* t) : target_(t) { }
 
   Status Append(const Slice& data) override { return target_->Append(data); }
+  Status PositionedAppend(const Slice& data, uint64_t offset) override {
+    return target_->PositionedAppend(data, offset);
+  }
   Status Truncate(uint64_t size) override { return target_->Truncate(size); }
   Status Close() override { return target_->Close(); }
   Status Flush() override { return target_->Flush(); }

port/win/env_win.cc

@@ -704,7 +704,7 @@ class WinRandomAccessFile : public RandomAccessFile {
 
     // Unbuffered access, use internal buffer for reads
     if (!use_os_buffer_) {
-      buffer_.SetAlignment(alignment);
+      buffer_.Alignment(alignment);
       // Random read, no need in a big buffer
       // We read things in database blocks which are likely to be similar to
       // the alignment we use.
@@ -734,7 +734,7 @@ class WinRandomAccessFile : public RandomAccessFile {
       // Let's see if at least some of the requested data is already
       // in the buffer
       if (offset >= buffered_start_ &&
-          offset < (buffered_start_ + buffer_.GetCurrentSize())) {
+          offset < (buffered_start_ + buffer_.CurrentSize())) {
         size_t buffer_offset = offset - buffered_start_;
         r = buffer_.Read(dest, buffer_offset, left);
         assert(r >= 0);
@@ -747,7 +747,7 @@ class WinRandomAccessFile : public RandomAccessFile {
       // Still some left or none was buffered
       if (left > 0) {
         // Figure out the start/end offset for reading and amount to read
-        const size_t alignment = buffer_.GetAlignment();
+        const size_t alignment = buffer_.Alignment();
         const size_t start_page_start =
             TruncateToPageBoundary(alignment, offset);
         const size_t end_page_start =
@@ -755,18 +755,18 @@ class WinRandomAccessFile : public RandomAccessFile {
         const size_t actual_bytes_toread =
             (end_page_start - start_page_start) + alignment;
 
-        if (buffer_.GetCapacity() < actual_bytes_toread) {
+        if (buffer_.Capacity() < actual_bytes_toread) {
           buffer_.AllocateNewBuffer(actual_bytes_toread);
         } else {
           buffer_.Clear();
         }
 
         SSIZE_T read = 0;
-        read = pread(hFile_, buffer_.GetDestination(), actual_bytes_toread,
+        read = pread(hFile_, buffer_.Destination(), actual_bytes_toread,
                       start_page_start);
 
         if (read > 0) {
-          buffer_.SetSize(read);
+          buffer_.Size(read);
           buffered_start_ = start_page_start;
 
           // Let's figure out how much we read from the users standpoint
@@ -797,7 +797,7 @@ class WinRandomAccessFile : public RandomAccessFile {
     return s;
   }
 
-  virtual bool ReaderWriterForward() const override {
+  virtual bool ShouldForwardRawRequest() const override {
     return true;
   }
 
@@ -880,7 +880,7 @@ class WinWritableFile : public WritableFile {
     return s;
   }
 
-  virtual Status Append(const Slice& data, uint64_t offset) override {
+  virtual Status PositionedAppend(const Slice& data, uint64_t offset) override {
     Status s;
 
     SSIZE_T ret = pwrite(hFile_, data.data(), 

util/aligned_buffer.h

@@ -25,7 +25,7 @@ inline size_t Roundup(size_t x, size_t y) {
 
 // This class is to manage an aligned user
 // allocated buffer for unbuffered I/O purposes
-// though it does not make a difference if you need a buffer.
+// though can be used for any purpose.
 class AlignedBuffer {
   size_t alignment_;
   std::unique_ptr<char[]> buf_;
@@ -58,19 +58,19 @@ public:
 
   AlignedBuffer& operator=(const AlignedBuffer&) = delete;
 
-  size_t GetAlignment() const {
+  size_t Alignment() const {
     return alignment_;
   }
 
-  size_t GetCapacity() const {
+  size_t Capacity() const {
     return capacity_;
   }
 
-  size_t GetCurrentSize() const {
+  size_t CurrentSize() const {
     return cursize_;
   }
 
-  const char* GetBufferStart() const {
+  const char* BufferStart() const {
     return bufstart_;
   }
 
@@ -78,7 +78,7 @@ public:
     cursize_ = 0;
   }
 
-  void SetAlignment(size_t alignment) {
+  void Alignment(size_t alignment) {
     assert(alignment > 0);
     assert((alignment & (alignment - 1)) == 0);
     alignment_ = alignment;
@@ -143,11 +143,11 @@ public:
   }
 
   // Returns place to start writing
-  char* GetDestination() {
+  char* Destination() {
     return bufstart_ + cursize_;
   }
 
-  void SetSize(size_t cursize) {
+  void Size(size_t cursize) {
     cursize_ = cursize;
   }
 };

util/file_reader_writer.cc

@@ -20,6 +20,11 @@
 #include "util/sync_point.h"
 
 namespace rocksdb {
+
+namespace {
+  const size_t c_OneMb = (1 << 20);
+}
+
 Status SequentialFileReader::Read(size_t n, Slice* result, char* scratch) {
   Status s = file_->Read(n, result, scratch);
   IOSTATS_ADD(bytes_read, result->size());
@@ -62,26 +67,26 @@ Status WritableFileWriter::Append(const Slice& data) {
 
   // Flush only when I/O is buffered
   if (use_os_buffer_ &&
-    (buf_.GetCapacity() - buf_.GetCurrentSize()) < left) {
-    if (buf_.GetCurrentSize() > 0) {
+    (buf_.Capacity() - buf_.CurrentSize()) < left) {
+    if (buf_.CurrentSize() > 0) {
       s = Flush();
       if (!s.ok()) {
         return s;
       }
     }
 
-    if (buf_.GetCapacity() < (1 << 20)) {
-      size_t desiredCapacity = buf_.GetCapacity() * 2;
-      desiredCapacity = std::min(desiredCapacity, size_t(1 << 20));
+    if (buf_.Capacity() < c_OneMb) {
+      size_t desiredCapacity = buf_.Capacity() * 2;
+      desiredCapacity = std::min(desiredCapacity, c_OneMb);
       buf_.AllocateNewBuffer(desiredCapacity);
     }
-    assert(buf_.GetCurrentSize() == 0);
+    assert(buf_.CurrentSize() == 0);
   }
 
   // We never write directly to disk with unbuffered I/O on.
   // or we simply use it for its original purpose to accumulate many small
   // chunks
-  if (!use_os_buffer_ || (buf_.GetCapacity() >= left)) {
+  if (!use_os_buffer_ || (buf_.Capacity() >= left)) {
     while (left > 0) {
       size_t appended = buf_.Append(src, left);
       left -= appended;
@@ -96,16 +101,16 @@ Status WritableFileWriter::Append(const Slice& data) {
         // We double the buffer here because
         // Flush calls do not keep up with the incoming bytes
         // This is the only place when buffer is changed with unbuffered I/O
-        if (buf_.GetCapacity() < (1 << 20)) {
-          size_t desiredCapacity = buf_.GetCapacity() * 2;
-          desiredCapacity = std::min(desiredCapacity, size_t(1 << 20));
+        if (buf_.Capacity() < (1 << 20)) {
+          size_t desiredCapacity = buf_.Capacity() * 2;
+          desiredCapacity = std::min(desiredCapacity, c_OneMb);
           buf_.AllocateNewBuffer(desiredCapacity);
         }
       }
     }
   } else {
     // Writing directly to file bypassing the buffer
-    assert(buf_.GetCurrentSize() == 0);
+    assert(buf_.CurrentSize() == 0);
     s = WriteBuffered(src, left);
   }
 
@@ -153,9 +158,9 @@ Status WritableFileWriter::Flush() {
   Status s;
   TEST_KILL_RANDOM(rocksdb_kill_odds * REDUCE_ODDS2);
 
-  if (buf_.GetCurrentSize() > 0) {
+  if (buf_.CurrentSize() > 0) {
     if (use_os_buffer_) {
-      s = WriteBuffered(buf_.GetBufferStart(), buf_.GetCurrentSize());
+      s = WriteBuffered(buf_.BufferStart(), buf_.CurrentSize());
     } else {
       s = WriteUnbuffered();
     }
@@ -260,7 +265,7 @@ size_t WritableFileWriter::RequestToken(size_t bytes, bool align) {
       // Here we may actually require more than burst and block
       // but we can not write less than one page at a time on unbuffered
       // thus we may want not to use ratelimiter s
-      size_t alignment = buf_.GetAlignment();
+      size_t alignment = buf_.Alignment();
       bytes = std::max(alignment, TruncateToPageBoundary(alignment, bytes));
     }
     rate_limiter_->Request(bytes, io_priority);
@@ -294,7 +299,7 @@ Status WritableFileWriter::WriteBuffered(const char* data, size_t size) {
     left -= allowed;
     src += allowed;
   }
-  buf_.SetSize(0);
+  buf_.Size(0);
   return s;
 }
 
@@ -311,25 +316,25 @@ Status WritableFileWriter::WriteUnbuffered() {
   Status s;
 
   assert(!use_os_buffer_);
-  const size_t alignment = buf_.GetAlignment();
+  const size_t alignment = buf_.Alignment();
   assert((next_write_offset_ % alignment) == 0);
 
   // Calculate whole page final file advance if all writes succeed
   size_t file_advance =
-    TruncateToPageBoundary(alignment, buf_.GetCurrentSize());
+    TruncateToPageBoundary(alignment, buf_.CurrentSize());
 
   // Calculate the leftover tail, we write it here padded with zeros BUT we
   // will write
   // it again in the future either on Close() OR when the current whole page
   // fills out
-  size_t leftover_tail = buf_.GetCurrentSize() - file_advance;
+  size_t leftover_tail = buf_.CurrentSize() - file_advance;
 
   // Round up and pad
   buf_.PadToAlignmentWith(0);
 
-  const char* src = buf_.GetBufferStart();
+  const char* src = buf_.BufferStart();
   uint64_t write_offset = next_write_offset_;
-  size_t left = buf_.GetCurrentSize();
+  size_t left = buf_.CurrentSize();
 
   while (left > 0) {
     // Check how much is allowed
@@ -339,9 +344,9 @@ Status WritableFileWriter::WriteUnbuffered() {
       IOSTATS_TIMER_GUARD(write_nanos);
       TEST_SYNC_POINT("WritableFileWriter::Flush:BeforeAppend");
       // Unbuffered writes must be positional
-      s = writable_file_->Append(Slice(src, size), write_offset);
+      s = writable_file_->PositionedAppend(Slice(src, size), write_offset);
       if (!s.ok()) {
-        buf_.SetSize(file_advance + leftover_tail);
+        buf_.Size(file_advance + leftover_tail);
         return s;
       }
     }
@@ -375,7 +380,7 @@ class ReadaheadRandomAccessFile : public RandomAccessFile {
      size_t readahead_size)
      : file_(std::move(file)),
        readahead_size_(readahead_size),
-       forward_calls_(file_->ReaderWriterForward()),
+       forward_calls_(file_->ShouldForwardRawRequest()),
        buffer_(new char[readahead_size_]),
        buffer_offset_(0),
        buffer_len_(0) {}
@@ -404,7 +409,7 @@ class ReadaheadRandomAccessFile : public RandomAccessFile {
     // if offset between [buffer_offset_, buffer_offset_ + buffer_len>
     if (offset >= buffer_offset_ && offset < buffer_len_ + buffer_offset_) {
       uint64_t offset_in_buffer = offset - buffer_offset_;
-      copied = std::min(static_cast<uint64_t>(buffer_len_)-offset_in_buffer,
+      copied = std::min(static_cast<uint64_t>(buffer_len_) - offset_in_buffer,
         static_cast<uint64_t>(n));
       memcpy(scratch, buffer_.get() + offset_in_buffer, copied);
       if (copied == n) {
@@ -458,8 +463,9 @@ class ReadaheadRandomAccessFile : public RandomAccessFile {
 
 std::unique_ptr<RandomAccessFile> NewReadaheadRandomAccessFile(
     std::unique_ptr<RandomAccessFile>&& file, size_t readahead_size) {
-  return std::make_unique<ReadaheadRandomAccessFile> (
-     std::move(file), readahead_size);
+  std::unique_ptr<RandomAccessFile> result(
+    new ReadaheadRandomAccessFile(std::move(file), readahead_size));
+  return result;
 }
 
 }  // namespace rocksdb

util/file_reader_writer.h

@@ -122,7 +122,7 @@ class WritableFileWriter {
         bytes_per_sync_(options.bytes_per_sync),
         rate_limiter_(options.rate_limiter) {
 
-    buf_.SetAlignment(writable_file_->GetRequiredBufferAlignment());
+    buf_.Alignment(writable_file_->GetRequiredBufferAlignment());
     buf_.AllocateNewBuffer(65536);
   }