logMessageBuffer.hpp revision 11209:c84a6ce067ad
1/* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24#ifndef SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP 25#define SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP 26 27#include "logging/logDecorations.hpp" 28#include "logging/logLevel.hpp" 29#include "memory/allocation.hpp" 30 31class LogMessageBuffer : public StackObj { 32 friend class LogMessageTest; 33 protected: 34 struct LogLine VALUE_OBJ_CLASS_SPEC { 35 LogLevelType level; 36 size_t message_offset; 37 }; 38 static const size_t InitialLineCapacity = 10; 39 static const size_t InitialMessageBufferCapacity = 1024; 40 41 size_t _message_buffer_size; 42 size_t _message_buffer_capacity; 43 char* _message_buffer; 44 45 size_t _line_count; 46 size_t _line_capacity; 47 LogLine* _lines; 48 49 bool _allocated; 50 LogLevelType _least_detailed_level; 51 size_t (*_prefix_fn)(char*, size_t); 52 53 void initialize_buffers(); 54 55 private: 56 // Forbid copy assignment and copy constructor. 57 void operator=(const LogMessageBuffer& ref) {} 58 LogMessageBuffer(const LogMessageBuffer& ref) {} 59 60 public: 61 LogMessageBuffer(); 62 ~LogMessageBuffer(); 63 64 class Iterator { 65 private: 66 const LogMessageBuffer& _message; 67 size_t _current_line_index; 68 LogLevelType _level; 69 LogDecorations &_decorations; 70 71 void skip_messages_with_finer_level(); 72 73 public: 74 Iterator(const LogMessageBuffer& message, LogLevelType level, LogDecorations& decorations) 75 : _message(message), _level(level), _decorations(decorations), _current_line_index(0) { 76 skip_messages_with_finer_level(); 77 } 78 79 void operator++(int) { 80 _current_line_index++; 81 skip_messages_with_finer_level(); 82 } 83 84 bool is_at_end() { 85 return _current_line_index == _message._line_count; 86 } 87 88 const char* message() const { 89 return _message._message_buffer + _message._lines[_current_line_index].message_offset; 90 } 91 92 const LogDecorations& decorations() { 93 _decorations.set_level(_message._lines[_current_line_index].level); 94 return _decorations; 95 } 96 }; 97 98 void reset(); 99 100 LogLevelType least_detailed_level() const { 101 return _least_detailed_level; 102 } 103 104 Iterator iterator(LogLevelType level, LogDecorations& decorations) const { 105 return Iterator(*this, level, decorations); 106 } 107 108 // Lines in LogMessageBuffers are not automatically prefixed based on tags 109 // like regular simple messages (see LogPrefix.hpp for more about prefixes). 110 // It is, however, possible to specify a prefix per LogMessageBuffer, 111 // using set_prefix(). Lines added to the LogMessageBuffer after a prefix 112 // function has been set will be prefixed automatically. 113 // Setting this to NULL will disable prefixing. 114 void set_prefix(size_t (*prefix_fn)(char*, size_t)) { 115 _prefix_fn = prefix_fn; 116 } 117 118 ATTRIBUTE_PRINTF(3, 4) 119 void write(LogLevelType level, const char* fmt, ...); 120 121 ATTRIBUTE_PRINTF(3, 0) 122 virtual void vwrite(LogLevelType level, const char* fmt, va_list args); 123 124#define LOG_LEVEL(level, name) \ 125 LogMessageBuffer& v##name(const char* fmt, va_list args) ATTRIBUTE_PRINTF(2, 0); \ 126 LogMessageBuffer& name(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3); 127 LOG_LEVEL_LIST 128#undef LOG_LEVEL 129}; 130 131#endif // SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP 132