Method LoadFileInfo

storage/sstable/reader/sstable_reader_impl.cpp:22–116

SSTableReader internal implementation.

// SSTableReader internal implementation.
bool SSTableReader::Impl::LoadFileInfo(File *file_base,
                                       hfile::DataIndex *data_index,
                                       hfile::FileInfo *file_info,
                                       hfile::FileTrailer *file_trailer) {
    // Load file trailer
    const int tailer_size = hfile::FileTrailer::TrailerSize();
    bool s = file_base->Seek(-tailer_size, SEEK_END);

    int64_t current_pos = file_base->Tell();
    file_base->Seek(0, SEEK_END);
    LOG(INFO)<< "current_pos:" << current_pos << ", file size:" << file_base->Tell();
    file_base->Seek(current_pos, SEEK_SET);

    if (!s) {
        LOG(ERROR)<< "Fail to seek";
        return false;
    }
    std::string buffer;
    buffer.resize(tailer_size);
    int64_t size = file_base->Read((void*) buffer.c_str(), tailer_size);
    if (tailer_size != size) {
        LOG(ERROR)<< "Read file trailer failed. read size:" << buffer.size()
        << ",TrailerSize: " << tailer_size;
        return false;
    }
    if (!file_trailer->DecodeFromString(buffer)) {
        LOG(ERROR)<< "parse file trailer failed, invalid format!";
        return false;
    }

    // if don't need file info, just return
    if (!file_info)
        return true;
    int64_t file_info_length = file_trailer->data_index_offset()
                    - file_trailer->file_info_offset();
    if (file_info_length < 0) {
        LOG(ERROR)<< "get invalid file info length: " << file_info_length;
        return false;
    }

    s = file_base->Seek(file_trailer->file_info_offset(), SEEK_SET);
    if (!s) {
        LOG(ERROR)<< "Fail to seek file";
        return false;
    }

    buffer.resize(file_info_length);
    size = file_base->Read((void*) buffer.c_str(), file_info_length);
    if (size != file_info_length) {
        LOG(ERROR)<< "read file info failed";
        return false;
    }

    if (!file_info->DecodeFromString(buffer)) {
        LOG(ERROR)<< "parse file info failed, invalid format!";
        return false;
    }