1 files changed, 508 insertions, 0 deletions
diff --git a/src/rocksdb/port/win/io_win.h b/src/rocksdb/port/win/io_win.h
new file mode 100644
index 000000000..a4fee8346
--- /dev/null
+++ b/src/rocksdb/port/win/io_win.h
@@ -0,0 +1,508 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+#pragma once
+
+#include <stdint.h>
+#include <windows.h>
+
+#include <mutex>
+#include <string>
+
+#include "rocksdb/file_system.h"
+#include "rocksdb/status.h"
+#include "util/aligned_buffer.h"
+#include "util/string_util.h"
+
+namespace ROCKSDB_NAMESPACE {
+namespace port {
+
+std::string GetWindowsErrSz(DWORD err);
+
+inline IOStatus IOErrorFromWindowsError(const std::string& context, DWORD err) {
+  return ((err == ERROR_HANDLE_DISK_FULL) || (err == ERROR_DISK_FULL))
+             ? IOStatus::NoSpace(context, GetWindowsErrSz(err))
+         : ((err == ERROR_FILE_NOT_FOUND) || (err == ERROR_PATH_NOT_FOUND))
+             ? IOStatus::PathNotFound(context, GetWindowsErrSz(err))
+             : IOStatus::IOError(context, GetWindowsErrSz(err));
+}
+
+inline IOStatus IOErrorFromLastWindowsError(const std::string& context) {
+  return IOErrorFromWindowsError(context, GetLastError());
+}
+
+inline IOStatus IOError(const std::string& context, int err_number) {
+  return (err_number == ENOSPC)
+             ? IOStatus::NoSpace(context, errnoStr(err_number).c_str())
+         : (err_number == ENOENT)
+             ? IOStatus::PathNotFound(context, errnoStr(err_number).c_str())
+             : IOStatus::IOError(context, errnoStr(err_number).c_str());
+}
+
+class WinFileData;
+
+IOStatus pwrite(const WinFileData* file_data, const Slice& data,
+                uint64_t offset, size_t& bytes_written);
+
+IOStatus pread(const WinFileData* file_data, char* src, size_t num_bytes,
+               uint64_t offset, size_t& bytes_read);
+
+IOStatus fallocate(const std::string& filename, HANDLE hFile, uint64_t to_size);
+
+IOStatus ftruncate(const std::string& filename, HANDLE hFile, uint64_t toSize);
+
+size_t GetUniqueIdFromFile(HANDLE hFile, char* id, size_t max_size);
+
+class WinFileData {
+ protected:
+  const std::string filename_;
+  HANDLE hFile_;
+  // If true, the I/O issued would be direct I/O which the buffer
+  // will need to be aligned (not sure there is a guarantee that the buffer
+  // passed in is aligned).
+  const bool use_direct_io_;
+  const size_t sector_size_;
+
+ public:
+  // We want this class be usable both for inheritance (prive
+  // or protected) and for containment so __ctor and __dtor public
+  WinFileData(const std::string& filename, HANDLE hFile, bool direct_io);
+
+  virtual ~WinFileData() { this->CloseFile(); }
+
+  bool CloseFile() {
+    bool result = true;
+
+    if (hFile_ != NULL && hFile_ != INVALID_HANDLE_VALUE) {
+      result = ::CloseHandle(hFile_);
+      assert(result);
+      hFile_ = NULL;
+    }
+    return result;
+  }
+
+  const std::string& GetName() const { return filename_; }
+
+  HANDLE GetFileHandle() const { return hFile_; }
+
+  bool use_direct_io() const { return use_direct_io_; }
+
+  size_t GetSectorSize() const { return sector_size_; }
+
+  bool IsSectorAligned(const size_t off) const;
+
+  WinFileData(const WinFileData&) = delete;
+  WinFileData& operator=(const WinFileData&) = delete;
+};
+
+class WinSequentialFile : protected WinFileData, public FSSequentialFile {
+  // Override for behavior change when creating a custom env
+  virtual IOStatus PositionedReadInternal(char* src, size_t numBytes,
+                                          uint64_t offset,
+                                          size_t& bytes_read) const;
+
+ public:
+  WinSequentialFile(const std::string& fname, HANDLE f,
+                    const FileOptions& options);
+
+  ~WinSequentialFile();
+
+  WinSequentialFile(const WinSequentialFile&) = delete;
+  WinSequentialFile& operator=(const WinSequentialFile&) = delete;
+
+  IOStatus Read(size_t n, const IOOptions& options, Slice* result,
+                char* scratch, IODebugContext* dbg) override;
+  IOStatus PositionedRead(uint64_t offset, size_t n, const IOOptions& options,
+                          Slice* result, char* scratch,
+                          IODebugContext* dbg) override;
+
+  IOStatus Skip(uint64_t n) override;
+
+  IOStatus InvalidateCache(size_t offset, size_t length) override;
+
+  virtual bool use_direct_io() const override {
+    return WinFileData::use_direct_io();
+  }
+};
+
+// mmap() based random-access
+class WinMmapReadableFile : private WinFileData, public FSRandomAccessFile {
+  HANDLE hMap_;
+
+  const void* mapped_region_;
+  const size_t length_;
+
+ public:
+  // mapped_region_[0,length-1] contains the mmapped contents of the file.
+  WinMmapReadableFile(const std::string& fileName, HANDLE hFile, HANDLE hMap,
+                      const void* mapped_region, size_t length);
+
+  ~WinMmapReadableFile();
+
+  WinMmapReadableFile(const WinMmapReadableFile&) = delete;
+  WinMmapReadableFile& operator=(const WinMmapReadableFile&) = delete;
+
+  IOStatus Read(uint64_t offset, size_t n, const IOOptions& options,
+                Slice* result, char* scratch,
+                IODebugContext* dbg) const override;
+
+  virtual IOStatus InvalidateCache(size_t offset, size_t length) override;
+
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+};
+
+// We preallocate and use memcpy to append new
+// data to the file.  This is safe since we either properly close the
+// file before reading from it, or for log files, the reading code
+// knows enough to skip zero suffixes.
+class WinMmapFile : private WinFileData, public FSWritableFile {
+ private:
+  HANDLE hMap_;
+
+  const size_t page_size_;  // We flush the mapping view in page_size
+  // increments. We may decide if this is a memory
+  // page size or SSD page size
+  const size_t
+      allocation_granularity_;  // View must start at such a granularity
+
+  size_t reserved_size_;  // Preallocated size
+
+  size_t mapping_size_;  // The max size of the mapping object
+  // we want to guess the final file size to minimize the remapping
+  size_t view_size_;  // How much memory to map into a view at a time
+
+  char* mapped_begin_;  // Must begin at the file offset that is aligned with
+  // allocation_granularity_
+  char* mapped_end_;
+  char* dst_;  // Where to write next  (in range [mapped_begin_,mapped_end_])
+  char* last_sync_;  // Where have we synced up to
+
+  uint64_t file_offset_;  // Offset of mapped_begin_ in file
+
+  // Do we have unsynced writes?
+  bool pending_sync_;
+
+  // Can only truncate or reserve to a sector size aligned if
+  // used on files that are opened with Unbuffered I/O
+  IOStatus TruncateFile(uint64_t toSize);
+
+  IOStatus UnmapCurrentRegion();
+
+  IOStatus MapNewRegion(const IOOptions& options, IODebugContext* dbg);
+
+  virtual IOStatus PreallocateInternal(uint64_t spaceToReserve);
+
+ public:
+  WinMmapFile(const std::string& fname, HANDLE hFile, size_t page_size,
+              size_t allocation_granularity, const FileOptions& options);
+
+  ~WinMmapFile();
+
+  WinMmapFile(const WinMmapFile&) = delete;
+  WinMmapFile& operator=(const WinMmapFile&) = delete;
+
+  IOStatus Append(const Slice& data, const IOOptions& options,
+                  IODebugContext* dbg) override;
+  IOStatus Append(const Slice& data, const IOOptions& opts,
+                  const DataVerificationInfo& /* verification_info */,
+                  IODebugContext* dbg) override {
+    return Append(data, opts, dbg);
+  }
+
+  // Means Close() will properly take care of truncate
+  // and it does not need any additional information
+  IOStatus Truncate(uint64_t size, const IOOptions& options,
+                    IODebugContext* dbg) override;
+
+  IOStatus Close(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Flush(const IOOptions& options, IODebugContext* dbg) override;
+
+  // Flush only data
+  IOStatus Sync(const IOOptions& options, IODebugContext* dbg) override;
+
+  /**
+   * Flush data as well as metadata to stable storage.
+   */
+  IOStatus Fsync(const IOOptions& options, IODebugContext* dbg) override;
+
+  /**
+   * Get the size of valid data in the file. This will not match the
+   * size that is returned from the filesystem because we use mmap
+   * to extend file by map_size every time.
+   */
+  uint64_t GetFileSize(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus InvalidateCache(size_t offset, size_t length) override;
+
+  IOStatus Allocate(uint64_t offset, uint64_t len, const IOOptions& options,
+                    IODebugContext* dbg) override;
+
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+};
+
+class WinRandomAccessImpl {
+ protected:
+  WinFileData* file_base_;
+  size_t alignment_;
+
+  // Override for behavior change when creating a custom env
+  virtual IOStatus PositionedReadInternal(char* src, size_t numBytes,
+                                          uint64_t offset,
+                                          size_t& bytes_read) const;
+
+  WinRandomAccessImpl(WinFileData* file_base, size_t alignment,
+                      const FileOptions& options);
+
+  virtual ~WinRandomAccessImpl() {}
+
+  IOStatus ReadImpl(uint64_t offset, size_t n, Slice* result,
+                    char* scratch) const;
+
+  size_t GetAlignment() const { return alignment_; }
+
+ public:
+  WinRandomAccessImpl(const WinRandomAccessImpl&) = delete;
+  WinRandomAccessImpl& operator=(const WinRandomAccessImpl&) = delete;
+};
+
+// pread() based random-access
+class WinRandomAccessFile
+    : private WinFileData,
+      protected WinRandomAccessImpl,  // Want to be able to override
+                                      // PositionedReadInternal
+      public FSRandomAccessFile {
+ public:
+  WinRandomAccessFile(const std::string& fname, HANDLE hFile, size_t alignment,
+                      const FileOptions& options);
+
+  ~WinRandomAccessFile();
+
+  IOStatus Read(uint64_t offset, size_t n, const IOOptions& options,
+                Slice* result, char* scratch,
+                IODebugContext* dbg) const override;
+
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+
+  virtual bool use_direct_io() const override {
+    return WinFileData::use_direct_io();
+  }
+
+  IOStatus InvalidateCache(size_t offset, size_t length) override;
+
+  virtual size_t GetRequiredBufferAlignment() const override;
+};
+
+// This is a sequential write class. It has been mimicked (as others) after
+// the original Posix class. We add support for unbuffered I/O on windows as
+// well
+// we utilize the original buffer as an alignment buffer to write directly to
+// file with no buffering.
+// No buffering requires that the provided buffer is aligned to the physical
+// sector size (SSD page size) and
+// that all SetFilePointer() operations to occur with such an alignment.
+// We thus always write in sector/page size increments to the drive and leave
+// the tail for the next write OR for Close() at which point we pad with zeros.
+// No padding is required for
+// buffered access.
+class WinWritableImpl {
+ protected:
+  WinFileData* file_data_;
+  const uint64_t alignment_;
+  uint64_t
+      next_write_offset_;  // Needed because Windows does not support O_APPEND
+  uint64_t reservedsize_;  // how far we have reserved space
+
+  virtual IOStatus PreallocateInternal(uint64_t spaceToReserve);
+
+  WinWritableImpl(WinFileData* file_data, size_t alignment);
+
+  ~WinWritableImpl() {}
+
+  uint64_t GetAlignment() const { return alignment_; }
+
+  IOStatus AppendImpl(const Slice& data);
+
+  // Requires that the data is aligned as specified by
+  // GetRequiredBufferAlignment()
+  IOStatus PositionedAppendImpl(const Slice& data, uint64_t offset);
+
+  IOStatus TruncateImpl(uint64_t size);
+
+  IOStatus CloseImpl();
+
+  IOStatus SyncImpl(const IOOptions& options, IODebugContext* dbg);
+
+  uint64_t GetFileNextWriteOffset() {
+    // Double accounting now here with WritableFileWriter
+    // and this size will be wrong when unbuffered access is used
+    // but tests implement their own writable files and do not use
+    // WritableFileWrapper
+    // so we need to squeeze a square peg through
+    // a round hole here.
+    return next_write_offset_;
+  }
+
+  IOStatus AllocateImpl(uint64_t offset, uint64_t len);
+
+ public:
+  WinWritableImpl(const WinWritableImpl&) = delete;
+  WinWritableImpl& operator=(const WinWritableImpl&) = delete;
+};
+
+class WinWritableFile : private WinFileData,
+                        protected WinWritableImpl,
+                        public FSWritableFile {
+ public:
+  WinWritableFile(const std::string& fname, HANDLE hFile, size_t alignment,
+                  size_t capacity, const FileOptions& options);
+
+  ~WinWritableFile();
+
+  IOStatus Append(const Slice& data, const IOOptions& options,
+                  IODebugContext* dbg) override;
+  IOStatus Append(const Slice& data, const IOOptions& opts,
+                  const DataVerificationInfo& /* verification_info */,
+                  IODebugContext* dbg) override {
+    return Append(data, opts, dbg);
+  }
+
+  // Requires that the data is aligned as specified by
+  // GetRequiredBufferAlignment()
+  IOStatus PositionedAppend(const Slice& data, uint64_t offset,
+                            const IOOptions& options,
+                            IODebugContext* dbg) override;
+  IOStatus PositionedAppend(const Slice& data, uint64_t offset,
+                            const IOOptions& opts,
+                            const DataVerificationInfo& /* verification_info */,
+                            IODebugContext* dbg) override {
+    return PositionedAppend(data, offset, opts, dbg);
+  }
+
+  // Need to implement this so the file is truncated correctly
+  // when buffered and unbuffered mode
+  IOStatus Truncate(uint64_t size, const IOOptions& options,
+                    IODebugContext* dbg) override;
+
+  IOStatus Close(const IOOptions& options, IODebugContext* dbg) override;
+
+  // write out the cached data to the OS cache
+  // This is now taken care of the WritableFileWriter
+  IOStatus Flush(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Sync(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Fsync(const IOOptions& options, IODebugContext* dbg) override;
+
+  virtual bool IsSyncThreadSafe() const override;
+
+  // Indicates if the class makes use of direct I/O
+  // Use PositionedAppend
+  virtual bool use_direct_io() const override;
+
+  virtual size_t GetRequiredBufferAlignment() const override;
+
+  uint64_t GetFileSize(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Allocate(uint64_t offset, uint64_t len, const IOOptions& options,
+                    IODebugContext* dbg) override;
+
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+};
+
+class WinRandomRWFile : private WinFileData,
+                        protected WinRandomAccessImpl,
+                        protected WinWritableImpl,
+                        public FSRandomRWFile {
+ public:
+  WinRandomRWFile(const std::string& fname, HANDLE hFile, size_t alignment,
+                  const FileOptions& options);
+
+  ~WinRandomRWFile() {}
+
+  // Indicates if the class makes use of direct I/O
+  // If false you must pass aligned buffer to Write()
+  virtual bool use_direct_io() const override;
+
+  // Use the returned alignment value to allocate aligned
+  // buffer for Write() when use_direct_io() returns true
+  virtual size_t GetRequiredBufferAlignment() const override;
+
+  // Write bytes in `data` at  offset `offset`, Returns Status::OK() on success.
+  // Pass aligned buffer when use_direct_io() returns true.
+  IOStatus Write(uint64_t offset, const Slice& data, const IOOptions& options,
+                 IODebugContext* dbg) override;
+
+  // Read up to `n` bytes starting from offset `offset` and store them in
+  // result, provided `scratch` size should be at least `n`.
+  // Returns Status::OK() on success.
+  IOStatus Read(uint64_t offset, size_t n, const IOOptions& options,
+                Slice* result, char* scratch,
+                IODebugContext* dbg) const override;
+
+  IOStatus Flush(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Sync(const IOOptions& options, IODebugContext* dbg) override;
+
+  IOStatus Fsync(const IOOptions& options, IODebugContext* dbg) override {
+    return Sync(options, dbg);
+  }
+
+  IOStatus Close(const IOOptions& options, IODebugContext* dbg) override;
+};
+
+class WinMemoryMappedBuffer : public MemoryMappedFileBuffer {
+ private:
+  HANDLE file_handle_;
+  HANDLE map_handle_;
+
+ public:
+  WinMemoryMappedBuffer(HANDLE file_handle, HANDLE map_handle, void* base,
+                        size_t size)
+      : MemoryMappedFileBuffer(base, size),
+        file_handle_(file_handle),
+        map_handle_(map_handle) {}
+  ~WinMemoryMappedBuffer() override;
+};
+
+class WinDirectory : public FSDirectory {
+  const std::string filename_;
+  HANDLE handle_;
+
+ public:
+  explicit WinDirectory(const std::string& filename, HANDLE h) noexcept
+      : filename_(filename), handle_(h) {
+    assert(handle_ != INVALID_HANDLE_VALUE);
+  }
+  ~WinDirectory() {
+    if (handle_ != NULL) {
+      IOStatus s = WinDirectory::Close(IOOptions(), nullptr);
+      s.PermitUncheckedError();
+    }
+  }
+  const std::string& GetName() const { return filename_; }
+  IOStatus Fsync(const IOOptions& options, IODebugContext* dbg) override;
+  IOStatus Close(const IOOptions& options, IODebugContext* dbg) override;
+
+  size_t GetUniqueId(char* id, size_t max_size) const override;
+};
+
+class WinFileLock : public FileLock {
+ public:
+  explicit WinFileLock(HANDLE hFile) : hFile_(hFile) {
+    assert(hFile != NULL);
+    assert(hFile != INVALID_HANDLE_VALUE);
+  }
+
+  ~WinFileLock();
+
+ private:
+  HANDLE hFile_;
+};
+}  // namespace port
+}  // namespace ROCKSDB_NAMESPACE