1 files changed, 258 insertions, 0 deletions
diff --git a/src/rocksdb/env/io_posix.h b/src/rocksdb/env/io_posix.h
new file mode 100644
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+++ b/src/rocksdb/env/io_posix.h
@@ -0,0 +1,258 @@
+//  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 <errno.h>
+#include <unistd.h>
+#include <atomic>
+#include <string>
+#include "rocksdb/env.h"
+
+// For non linux platform, the following macros are used only as place
+// holder.
+#if !(defined OS_LINUX) && !(defined CYGWIN) && !(defined OS_AIX)
+#define POSIX_FADV_NORMAL 0     /* [MC1] no further special treatment */
+#define POSIX_FADV_RANDOM 1     /* [MC1] expect random page refs */
+#define POSIX_FADV_SEQUENTIAL 2 /* [MC1] expect sequential page refs */
+#define POSIX_FADV_WILLNEED 3   /* [MC1] will need these pages */
+#define POSIX_FADV_DONTNEED 4   /* [MC1] dont need these pages */
+#endif
+
+namespace rocksdb {
+static std::string IOErrorMsg(const std::string& context,
+                              const std::string& file_name) {
+  if (file_name.empty()) {
+    return context;
+  }
+  return context + ": " + file_name;
+}
+
+// file_name can be left empty if it is not unkown.
+static Status IOError(const std::string& context, const std::string& file_name,
+                      int err_number) {
+  switch (err_number) {
+  case ENOSPC:
+    return Status::NoSpace(IOErrorMsg(context, file_name),
+                           strerror(err_number));
+  case ESTALE:
+    return Status::IOError(Status::kStaleFile);
+  case ENOENT:
+    return Status::PathNotFound(IOErrorMsg(context, file_name),
+                                strerror(err_number));
+  default:
+    return Status::IOError(IOErrorMsg(context, file_name),
+                           strerror(err_number));
+  }
+}
+
+class PosixHelper {
+ public:
+  static size_t GetUniqueIdFromFile(int fd, char* id, size_t max_size);
+};
+
+class PosixSequentialFile : public SequentialFile {
+ private:
+  std::string filename_;
+  FILE* file_;
+  int fd_;
+  bool use_direct_io_;
+  size_t logical_sector_size_;
+
+ public:
+  PosixSequentialFile(const std::string& fname, FILE* file, int fd,
+                      const EnvOptions& options);
+  virtual ~PosixSequentialFile();
+
+  virtual Status Read(size_t n, Slice* result, char* scratch) override;
+  virtual Status PositionedRead(uint64_t offset, size_t n, Slice* result,
+                                char* scratch) override;
+  virtual Status Skip(uint64_t n) override;
+  virtual Status InvalidateCache(size_t offset, size_t length) override;
+  virtual bool use_direct_io() const override { return use_direct_io_; }
+  virtual size_t GetRequiredBufferAlignment() const override {
+    return logical_sector_size_;
+  }
+};
+
+class PosixRandomAccessFile : public RandomAccessFile {
+ protected:
+  std::string filename_;
+  int fd_;
+  bool use_direct_io_;
+  size_t logical_sector_size_;
+
+ public:
+  PosixRandomAccessFile(const std::string& fname, int fd,
+                        const EnvOptions& options);
+  virtual ~PosixRandomAccessFile();
+
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+                      char* scratch) const override;
+
+  virtual Status Prefetch(uint64_t offset, size_t n) override;
+
+#if defined(OS_LINUX) || defined(OS_MACOSX) || defined(OS_AIX)
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+#endif
+  virtual void Hint(AccessPattern pattern) override;
+  virtual Status InvalidateCache(size_t offset, size_t length) override;
+  virtual bool use_direct_io() const override { return use_direct_io_; }
+  virtual size_t GetRequiredBufferAlignment() const override {
+    return logical_sector_size_;
+  }
+};
+
+class PosixWritableFile : public WritableFile {
+ protected:
+  const std::string filename_;
+  const bool use_direct_io_;
+  int fd_;
+  uint64_t filesize_;
+  size_t logical_sector_size_;
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+  bool allow_fallocate_;
+  bool fallocate_with_keep_size_;
+#endif
+
+ public:
+  explicit PosixWritableFile(const std::string& fname, int fd,
+                             const EnvOptions& options);
+  virtual ~PosixWritableFile();
+
+  // Need to implement this so the file is truncated correctly
+  // with direct I/O
+  virtual Status Truncate(uint64_t size) override;
+  virtual Status Close() override;
+  virtual Status Append(const Slice& data) override;
+  virtual Status PositionedAppend(const Slice& data, uint64_t offset) override;
+  virtual Status Flush() override;
+  virtual Status Sync() override;
+  virtual Status Fsync() override;
+  virtual bool IsSyncThreadSafe() const override;
+  virtual bool use_direct_io() const override { return use_direct_io_; }
+  virtual void SetWriteLifeTimeHint(Env::WriteLifeTimeHint hint) override;
+  virtual uint64_t GetFileSize() override;
+  virtual Status InvalidateCache(size_t offset, size_t length) override;
+  virtual size_t GetRequiredBufferAlignment() const override {
+    return logical_sector_size_;
+  }
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+  virtual Status Allocate(uint64_t offset, uint64_t len) override;
+#endif
+#ifdef ROCKSDB_RANGESYNC_PRESENT
+  virtual Status RangeSync(uint64_t offset, uint64_t nbytes) override;
+#endif
+#ifdef OS_LINUX
+  virtual size_t GetUniqueId(char* id, size_t max_size) const override;
+#endif
+};
+
+// mmap() based random-access
+class PosixMmapReadableFile : public RandomAccessFile {
+ private:
+  int fd_;
+  std::string filename_;
+  void* mmapped_region_;
+  size_t length_;
+
+ public:
+  PosixMmapReadableFile(const int fd, const std::string& fname, void* base,
+                        size_t length, const EnvOptions& options);
+  virtual ~PosixMmapReadableFile();
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+                      char* scratch) const override;
+  virtual Status InvalidateCache(size_t offset, size_t length) override;
+};
+
+class PosixMmapFile : public WritableFile {
+ private:
+  std::string filename_;
+  int fd_;
+  size_t page_size_;
+  size_t map_size_;       // How much extra memory to map at a time
+  char* base_;            // The mapped region
+  char* limit_;           // Limit of the mapped region
+  char* dst_;             // Where to write next  (in range [base_,limit_])
+  char* last_sync_;       // Where have we synced up to
+  uint64_t file_offset_;  // Offset of base_ in file
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+  bool allow_fallocate_;  // If false, fallocate calls are bypassed
+  bool fallocate_with_keep_size_;
+#endif
+
+  // Roundup x to a multiple of y
+  static size_t Roundup(size_t x, size_t y) { return ((x + y - 1) / y) * y; }
+
+  size_t TruncateToPageBoundary(size_t s) {
+    s -= (s & (page_size_ - 1));
+    assert((s % page_size_) == 0);
+    return s;
+  }
+
+  Status MapNewRegion();
+  Status UnmapCurrentRegion();
+  Status Msync();
+
+ public:
+  PosixMmapFile(const std::string& fname, int fd, size_t page_size,
+                const EnvOptions& options);
+  ~PosixMmapFile();
+
+  // Means Close() will properly take care of truncate
+  // and it does not need any additional information
+  virtual Status Truncate(uint64_t /*size*/) override { return Status::OK(); }
+  virtual Status Close() override;
+  virtual Status Append(const Slice& data) override;
+  virtual Status Flush() override;
+  virtual Status Sync() override;
+  virtual Status Fsync() override;
+  virtual uint64_t GetFileSize() override;
+  virtual Status InvalidateCache(size_t offset, size_t length) override;
+#ifdef ROCKSDB_FALLOCATE_PRESENT
+  virtual Status Allocate(uint64_t offset, uint64_t len) override;
+#endif
+};
+
+class PosixRandomRWFile : public RandomRWFile {
+ public:
+  explicit PosixRandomRWFile(const std::string& fname, int fd,
+                             const EnvOptions& options);
+  virtual ~PosixRandomRWFile();
+
+  virtual Status Write(uint64_t offset, const Slice& data) override;
+
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+                      char* scratch) const override;
+
+  virtual Status Flush() override;
+  virtual Status Sync() override;
+  virtual Status Fsync() override;
+  virtual Status Close() override;
+
+ private:
+  const std::string filename_;
+  int fd_;
+};
+
+struct PosixMemoryMappedFileBuffer : public MemoryMappedFileBuffer {
+  PosixMemoryMappedFileBuffer(void* _base, size_t _length)
+      : MemoryMappedFileBuffer(_base, _length) {}
+  virtual ~PosixMemoryMappedFileBuffer();
+};
+
+class PosixDirectory : public Directory {
+ public:
+  explicit PosixDirectory(int fd) : fd_(fd) {}
+  ~PosixDirectory();
+  virtual Status Fsync() override;
+
+ private:
+  int fd_;
+};
+
+}  // namespace rocksdb