Method read

include/jsoncons/source.hpp:342–395

        }

        std::size_t read(value_type* p, std::size_t length)
        {
            std::size_t len = 0;
            if (length_ > 0)
            {
                len = (std::min)(length_, length);
                std::memcpy(p, data_, len*sizeof(value_type));
                data_ += len;
                length_ -= len;
                position_ += len;
            }
            if (length - len == 0)
            {
                return len;
            }
            else if (length - len < buffer_size_)
            {
                fill_buffer();
                if (length_ > 0)
                {
                    std::size_t len2 = (std::min)(length_, length-len);
                    std::memcpy(p+len, data_, len2*sizeof(value_type));
                    data_ += len2;
                    length_ -= len2;
                    position_ += len2;
                    len += len2;
                }
                return len;
            }
            else
            {
                if (stream_ptr_->eof())
                {
                    length_ = 0;
                    return 0;
                }
                JSONCONS_TRY
                {
                    std::streamsize count = sbuf_->sgetn(reinterpret_cast<char_type*>(p+len), length-len);
                    std::size_t len2 = static_cast<std::size_t>(count);
                    if (len2 < length-len)
                    {
                        stream_ptr_->clear(stream_ptr_->rdstate() | std::ios::eofbit);
                    }
                    len += len2;
                    position_ += len2;
                    return len;
                }
                JSONCONS_CATCH(const std::exception&)     
                {
                    stream_ptr_->clear(stream_ptr_->rdstate() | std::ios::badbit | std::ios::eofbit);
                    return 0;
                }
            }
        }
    private:
        void fill_buffer()