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tdutils/td/utils/port/FileFd.h

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+/*
+    This file is part of TON Blockchain Library.
+
+    TON Blockchain Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 2 of the License, or
+    (at your option) any later version.
+
+    TON Blockchain Library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with TON Blockchain Library.  If not, see <http://www.gnu.org/licenses/>.
+
+    Copyright 2017-2019 Telegram Systems LLP
+*/
+#pragma once
+
+#include "td/utils/port/config.h"
+
+#include "td/utils/common.h"
+#include "td/utils/port/detail/NativeFd.h"
+#include "td/utils/port/detail/PollableFd.h"
+#include "td/utils/port/IoSlice.h"
+#include "td/utils/port/Stat.h"
+#include "td/utils/Slice.h"
+#include "td/utils/Span.h"
+#include "td/utils/Status.h"
+
+namespace td {
+namespace detail {
+class FileFdImpl;
+}
+
+class FileFd {
+ public:
+  FileFd();
+  FileFd(FileFd &&);
+  FileFd &operator=(FileFd &&);
+  ~FileFd();
+  FileFd(const FileFd &) = delete;
+  FileFd &operator=(const FileFd &) = delete;
+
+  enum Flags : int32 { Write = 1, Read = 2, Truncate = 4, Create = 8, Append = 16, CreateNew = 32, Direct = 64 };
+  enum PrivateFlags : int32 { WinStat = 128 };
+
+  static Result<FileFd> open(CSlice filepath, int32 flags, int32 mode = 0600) TD_WARN_UNUSED_RESULT;
+  static FileFd from_native_fd(NativeFd fd) TD_WARN_UNUSED_RESULT;
+
+  Result<size_t> write(Slice slice) TD_WARN_UNUSED_RESULT;
+  Result<size_t> writev(Span<IoSlice> slices) TD_WARN_UNUSED_RESULT;
+  Result<size_t> read(MutableSlice slice) TD_WARN_UNUSED_RESULT;
+
+  Result<size_t> pwrite(Slice slice, int64 offset) TD_WARN_UNUSED_RESULT;
+  Result<size_t> pread(MutableSlice slice, int64 offset) const TD_WARN_UNUSED_RESULT;
+
+  enum class LockFlags { Write, Read, Unlock };
+  Status lock(const LockFlags flags, const string &path, int32 max_tries) TD_WARN_UNUSED_RESULT;
+  static void remove_local_lock(const string &path);
+
+  PollableFdInfo &get_poll_info();
+  const PollableFdInfo &get_poll_info() const;
+  void close();
+  bool empty() const;
+
+  Result<int64> get_size() const;
+
+  Result<Stat> stat() const;
+
+  Status sync() TD_WARN_UNUSED_RESULT;
+
+  Status seek(int64 position) TD_WARN_UNUSED_RESULT;
+
+  Status truncate_to_current_position(int64 current_position) TD_WARN_UNUSED_RESULT;
+
+  const NativeFd &get_native_fd() const;
+  NativeFd move_as_native_fd();
+
+ private:
+  unique_ptr<detail::FileFdImpl> impl_;
+
+  explicit FileFd(unique_ptr<detail::FileFdImpl> impl);
+};
+
+}  // namespace td