1 /* Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved. 2 3 This program is free software; you can redistribute it and/or modify 4 it under the terms of the GNU General Public License, version 2.0, 5 as published by the Free Software Foundation. 6 7 This program is also distributed with certain software (including 8 but not limited to OpenSSL) that is licensed under separate terms, 9 as designated in a particular file or component or in included license 10 documentation. The authors of MySQL hereby grant you an additional 11 permission to link the program and your derivative works with the 12 separately licensed software that they have included with MySQL. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License, version 2.0, for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ 22 23 #ifndef COMPRESSION_NONE_INCLUDED 24 #define COMPRESSION_NONE_INCLUDED 25 26 #include "base.h" 27 28 namespace binary_log { 29 namespace transaction { 30 namespace compression { 31 32 /** 33 This compressor does not compress. The only thing that it does 34 is to copy the data from the input to the output buffer. 35 */ 36 class None_comp : public Compressor { 37 public: 38 None_comp() = default; 39 40 /** 41 No op member function. 42 */ 43 virtual void set_compression_level(unsigned int compression_level) override; 44 45 /** 46 Shall get the compressor type code. 47 48 @return the compressor type code. 49 */ 50 virtual type compression_type_code() override; 51 52 /** 53 No op member function. 54 55 @return false on success, true otherwise. 56 */ 57 virtual bool open() override; 58 59 /** 60 This member function shall simply copy the input buffer to the 61 output buffer. It shall grow the output buffer if needed. 62 63 @param data a pointer to the buffer holding the data to compress 64 @param length the size of the data to compress. 65 66 @return false on success, true otherwise. 67 */ 68 virtual std::tuple<std::size_t, bool> compress(const unsigned char *data, 69 size_t length) override; 70 71 /** 72 No op member function. 73 74 @return false on success, true otherwise. 75 */ 76 virtual bool close() override; 77 }; 78 79 /** 80 This decompressor does not decompress. The only thing that it 81 does is to copy the data from the input to the output buffer. 82 */ 83 class None_dec : public Decompressor { 84 private: 85 None_dec &operator=(const None_dec &rhs) = delete; 86 None_dec(const None_dec &) = delete; 87 88 public: 89 None_dec() = default; 90 91 /** 92 Shall return the compression type code. 93 94 @return the compression type code. 95 */ 96 virtual type compression_type_code() override; 97 98 /** 99 No op member function. 100 101 @return false on success, true otherwise. 102 */ 103 virtual bool open() override; 104 105 /** 106 This member function shall simply copy the input buffer to the 107 output buffer. It shall grow the output buffer if needed. 108 109 @param data a pointer to the buffer holding the data to decompress 110 @param length the size of the data to decompress. 111 112 @return false on success, true otherwise. 113 */ 114 virtual std::tuple<std::size_t, bool> decompress(const unsigned char *data, 115 size_t length) override; 116 117 /** 118 No op member function. 119 120 @return false on success, true otherwise. 121 */ 122 virtual bool close() override; 123 }; 124 125 } // namespace compression 126 } // namespace transaction 127 } // namespace binary_log 128 #endif 129