library/cpp/yson_pull/detail/output/buffered.h


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#pragma once

#include <library/cpp/yson_pull/detail/macros.h>

#include <library/cpp/yson_pull/output.h>

#include <util/generic/strbuf.h>

namespace NYsonPull { 
    namespace NDetail { 
        namespace NOutput { 
            template <typename T> 
            class TBuffered: public NYsonPull::NOutput::IStream { 
                TArrayHolder<ui8> buffer_; 
                size_t size_; 

            public: 
                TBuffered(size_t buffer_size) 
                    : buffer_{new ui8[buffer_size]} 
                    , size_{buffer_size} { 
                    reset_buffer(); 
                } 

            protected: 
                void do_flush_buffer(TStringBuf extra) override { 
                    auto& buf = buffer(); 
                    if (!buf.is_empty()) { 
                        do_write({reinterpret_cast<const char*>(buf.begin()), buf.used()});
                        reset_buffer(); 
                    } 
                    if (extra.size() >= buf.available()) { 
                        do_write(extra); 
                    } else if (extra.size() > 0) {
                        ::memcpy(buf.pos(), extra.data(), extra.size()); 
                        buf.advance(extra.size()); 
                    } 
                } 

            private: 
                void do_write(TStringBuf data) { 
                    // CRTP dispatch 
                    static_cast<T*>(this)->write(data); 
                } 
 
                void reset_buffer() { 
                    buffer().reset(buffer_.Get(), buffer_.Get() + size_); 
                } 
            }; 
        }
    }     // namespace NDetail 
}