integrating the existing state of TON Storage / TON Payments / CPS Fift development branches

tddb/td/db/utils/BlobView.h

@@ -0,0 +1,67 @@
+/*
+    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/buffer.h"
+
+namespace td {
+class BlobViewImpl;
+
+class BlobView {
+ public:
+  BlobView();
+  explicit BlobView(std::unique_ptr<BlobViewImpl> impl);
+  BlobView(BlobView &&);
+  BlobView &operator=(BlobView &&);
+  ~BlobView();
+  td::Result<td::BufferSlice> to_buffer_slice();
+  td::Result<td::Slice> view(td::MutableSlice slice, td::uint64 offset);
+  td::Result<size_t> view_copy(td::MutableSlice slice, td::uint64 offset);
+  td::Result<size_t> write(td::Slice data, td::uint64 offset);
+  td::uint64 size();
+
+  explicit operator bool() const {
+    return bool(impl_);
+  }
+
+ private:
+  std::unique_ptr<BlobViewImpl> impl_;
+};
+
+class BufferSliceBlobView {
+ public:
+  static BlobView create(td::BufferSlice slice);
+};
+class FileBlobView {
+ public:
+  static td::Result<BlobView> create(td::CSlice file_path, td::uint64 file_size = 0);
+};
+class FileNoCacheBlobView {
+ public:
+  static td::Result<BlobView> create(td::CSlice file_path, td::uint64 file_size = 0, bool may_write = false);
+};
+class FileMemoryMappingBlobView {
+ public:
+  static td::Result<BlobView> create(td::CSlice file_path, td::uint64 file_size = 0);
+};
+
+// For testing purposes
+struct CycicBlobView {
+  static td::Result<td::BlobView> create(td::BufferSlice data, td::uint64 total_size);
+};
+}  // namespace td