Function ConstructAsMap

util/memory/blob.cpp:210–221

template <class TCounter, class T>
static inline TBlob ConstructAsMap(const T& t, EMappingMode mode) {
    TMemoryMap::EOpenMode openMode = (mode == EMappingMode::Precharged) ? (TMemoryMap::oRdOnly | TMemoryMap::oPrecharge) : TMemoryMap::oRdOnly;

    TMemoryMap map(t, openMode);
    const ui64 toMap = map.Length();

    if (toMap > Max<size_t>()) {
        ythrow yexception() << "can not map whole file(length = " << toMap << ")";
    }

    return ConstructFromMap<TCounter>(map, 0, static_cast<size_t>(toMap), mode);
}

TBlob TBlob::FromFileSingleThreaded(const TString& path, EMappingMode mode) {
    return ConstructAsMap<TSimpleCounter>(path, mode);