initial commit

crypto/vm/db/BlobView.cpp

@@ -0,0 +1,181 @@
+/*
+    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
+*/
+#include "vm/db/BlobView.h"
+
+#include "td/utils/port/FileFd.h"
+#include "td/utils/HashMap.h"
+
+#include "td/utils/format.h"
+#include "td/utils/port/RwMutex.h"
+#include "td/utils/port/MemoryMapping.h"
+
+#include <limits>
+#include <mutex>
+
+namespace vm {
+td::Result<td::Slice> BlobView::view(td::MutableSlice slice, td::uint64 offset) {
+  if (offset > size() || slice.size() > size() - offset) {
+    return td::Status::Error(PSLICE() << "BlobView: invalid range requested " << td::tag("slice offset", offset)
+                                      << td::tag("slice size", slice.size()) << td::tag("blob size", size()));
+  }
+  return view_impl(slice, offset);
+}
+namespace {
+class BufferSliceBlobViewImpl : public BlobView {
+ public:
+  BufferSliceBlobViewImpl(td::BufferSlice slice) : slice_(std::move(slice)) {
+  }
+  td::Result<td::Slice> view_impl(td::MutableSlice slice, td::uint64 offset) override {
+    // optimize anyway
+    if (offset > std::numeric_limits<std::size_t>::max()) {
+      return td::Slice();
+    }
+    return slice_.as_slice().substr(static_cast<std::size_t>(offset), slice.size());
+  }
+  td::uint64 size() override {
+    return slice_.size();
+  }
+
+ private:
+  td::BufferSlice slice_;
+};
+}  // namespace
+
+std::unique_ptr<BlobView> BufferSliceBlobView::create(td::BufferSlice slice) {
+  return std::make_unique<BufferSliceBlobViewImpl>(std::move(slice));
+}
+
+class FileBlobViewImpl : public BlobView {
+ public:
+  FileBlobViewImpl(td::FileFd fd, td::uint64 file_size) : fd_(std::move(fd)), file_size_(file_size) {
+  }
+
+  td::uint64 size() override {
+    return file_size_;
+  }
+  td::Result<td::Slice> view_impl(td::MutableSlice slice, td::uint64 offset) override {
+    CHECK(offset < size());
+    CHECK(size() - offset >= slice.size());
+    slice.truncate(file_size_ - offset);
+    auto first_page = offset / page_size;
+    auto last_page = (offset + slice.size() - 1) / page_size;
+    td::uint64 res_offset = 0;
+    for (auto page_i = first_page; page_i <= last_page; page_i++) {
+      auto page_offset = page_i * page_size;
+      auto from = td::max(page_offset, offset);
+      auto till = td::min(page_offset + page_size, offset + slice.size());
+      CHECK(from < till);
+      TRY_RESULT(page, load_page(page_i));
+      auto len = till - from;
+      slice.substr(res_offset, len).copy_from(page.substr(from - page_offset, len));
+      res_offset += len;
+    }
+    CHECK(slice.size() == res_offset);
+    total_view_size_ += slice.size();
+    return slice;
+  }
+  ~FileBlobViewImpl() {
+    //LOG(ERROR) << "LOADED " << pages_.size() << " " << total_view_size_;
+  }
+
+ private:
+  td::FileFd fd_;
+  td::uint64 file_size_;
+  const td::uint64 page_size = 4096;
+  td::uint64 total_view_size_{0};
+
+  td::RwMutex pages_rw_mutex_;
+  td::HashMap<td::uint64, td::BufferSlice> pages_;
+
+  std::mutex fd_mutex_;
+
+  td::Result<td::Slice> load_page(td::uint64 page_i) {
+    {
+      auto pages_guard = pages_rw_mutex_.lock_read();
+      auto it = pages_.find(page_i);
+      if (it != pages_.end()) {
+        return it->second.as_slice();
+      }
+    }
+
+    std::lock_guard<std::mutex> fd_guard(fd_mutex_);
+    {
+      auto pages_guard = pages_rw_mutex_.lock_read();
+      auto it = pages_.find(page_i);
+      if (it != pages_.end()) {
+        return it->second.as_slice();
+      }
+    }
+    auto offset = page_i * page_size;
+
+    auto size = td::min(file_size_ - offset, page_size);
+    auto buffer_slice = td::BufferSlice(size);
+    TRY_RESULT(read_size, fd_.pread(buffer_slice.as_slice(), offset));
+    if (read_size != buffer_slice.size()) {
+      return td::Status::Error("not enough data in file");
+    }
+
+    auto pages_guard = pages_rw_mutex_.lock_write();
+    auto &res = pages_[page_i];
+    res = std::move(buffer_slice);
+    return res.as_slice();
+  }
+};
+td::Result<std::unique_ptr<BlobView>> FileBlobView::create(td::CSlice file_path, td::uint64 file_size) {
+  TRY_RESULT(fd, td::FileFd::open(file_path, td::FileFd::Flags::Read));
+  TRY_RESULT(stat, fd.stat());
+  if (file_size == 0) {
+    file_size = stat.size_;
+  } else if (file_size != (td::uint64)stat.size_) {
+    return td::Status::Error("Wrong file size");
+  }
+  return std::make_unique<FileBlobViewImpl>(std::move(fd), file_size);
+}
+
+class FileMemoryMappingBlobViewImpl : public BlobView {
+ public:
+  FileMemoryMappingBlobViewImpl(td::MemoryMapping mapping) : mapping_(std::move(mapping)) {
+  }
+  td::Result<td::Slice> view_impl(td::MutableSlice slice, td::uint64 offset) override {
+    // optimize anyway
+    return mapping_.as_slice().substr(offset, slice.size());
+  }
+  td::uint64 size() override {
+    return mapping_.as_slice().size();
+  }
+
+ private:
+  td::MemoryMapping mapping_;
+};
+
+td::Result<std::unique_ptr<BlobView>> FileMemoryMappingBlobView::create(td::CSlice file_path, td::uint64 file_size) {
+  TRY_RESULT(fd, td::FileFd::open(file_path, td::FileFd::Flags::Read));
+  TRY_RESULT(stat, fd.stat());
+  if (file_size == 0) {
+    file_size = stat.size_;
+  } else if (file_size != (td::uint64)stat.size_) {
+    return td::Status::Error("Wrong file size");
+  }
+
+  TRY_RESULT(mapping, td::MemoryMapping::create_from_file(fd));
+
+  return std::make_unique<FileMemoryMappingBlobViewImpl>(std::move(mapping));
+}
+
+}  // namespace vm