1 /* 2 * Copyright (c) 2015, 2021, Oracle and/or its affiliates. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License, version 2.0, 6 * as published by the Free Software Foundation. 7 * 8 * This program is also distributed with certain software (including 9 * but not limited to OpenSSL) that is licensed under separate terms, 10 * as designated in a particular file or component or in included license 11 * documentation. The authors of MySQL hereby grant you an additional 12 * permission to link the program and your derivative works with the 13 * separately licensed software that they have included with MySQL. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License, version 2.0, for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 23 * 02110-1301 USA 24 */ 25 26 #ifndef _NGS_OUTPUT_BUFFER_H_ 27 #define _NGS_OUTPUT_BUFFER_H_ 28 29 #include <stdint.h> 30 #include <vector> 31 #include "ngs_common/protocol_protobuf.h" 32 33 #include "ngs_common/types.h" 34 #include "ngs/protocol/buffer.h" 35 #include "ngs/memory.h" 36 37 38 namespace ngs 39 { 40 41 class Output_buffer; 42 typedef ngs::Memory_instrumented<Output_buffer>::Unique_ptr Output_buffer_unique_ptr; 43 44 class Output_buffer : public Buffer, public google::protobuf::io::ZeroCopyOutputStream 45 { 46 public: 47 Output_buffer(Page_pool& page_pool); 48 49 bool add_int32(int32_t i); 50 bool add_int8(int8_t i); 51 bool add_bytes(const char *data, size_t length); 52 53 Const_buffer_sequence get_buffers(); 54 55 void save_state(); 56 void rollback(); // restores last saved state 57 58 public: 59 virtual bool Next(void** data, int* size); 60 virtual void BackUp(int count); 61 62 virtual int64_t ByteCount() const; 63 64 private: 65 size_t m_saved_length; 66 }; 67 68 } // namespace ngs 69 70 #endif // _NGS_OUTPUT_BUFFER_H_ 71