Function Peek4

rapidjson/istreamwrapper.h:79–95

For encoding detection only.

    // For encoding detection only.
    const Ch* Peek4() const {
        RAPIDJSON_ASSERT(sizeof(Ch) == 1); // Only usable for byte stream.
        int i;
        bool hasError = false;
        for (i = 0; i < 4; ++i) {
            typename StreamType::int_type c = stream_.get();
            if (c == StreamType::traits_type::eof()) {
                hasError = true;
                stream_.clear();
                break;
            }
            peekBuffer_[i] = static_cast<Ch>(c);
        }
        for (--i; i >= 0; --i)
            stream_.putback(peekBuffer_[i]);
        return !hasError ? peekBuffer_ : 0;
    }

private:
    BasicIStreamWrapper(const BasicIStreamWrapper&);