| /** |
| * Copyright (c) 2016-present, Facebook, Inc. |
| * All rights reserved. |
| * |
| * This source code is licensed under the BSD-style license found in the |
| * LICENSE file in the root directory of this source tree. An additional grant |
| * of patent rights can be found in the PATENTS file in the same directory. |
| */ |
| #include "SkippableFrame.h" |
| #include "mem.h" |
| #include "utils/Range.h" |
| |
| #include <cstdio> |
| |
| using namespace pzstd; |
| |
| SkippableFrame::SkippableFrame(std::uint32_t size) : frameSize_(size) { |
| MEM_writeLE32(data_.data(), kSkippableFrameMagicNumber); |
| MEM_writeLE32(data_.data() + 4, kFrameContentsSize); |
| MEM_writeLE32(data_.data() + 8, frameSize_); |
| } |
| |
| /* static */ std::size_t SkippableFrame::tryRead(ByteRange bytes) { |
| if (bytes.size() < SkippableFrame::kSize || |
| MEM_readLE32(bytes.begin()) != kSkippableFrameMagicNumber || |
| MEM_readLE32(bytes.begin() + 4) != kFrameContentsSize) { |
| return 0; |
| } |
| return MEM_readLE32(bytes.begin() + 8); |
| } |