1 /* 2 * Copyright (c) 2015, 2019, 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_LOGGING_LOGCONFIGURATION_HPP 25 #define SHARE_LOGGING_LOGCONFIGURATION_HPP 26 27 #include "logging/logLevel.hpp" 28 #include "memory/allocation.hpp" 29 #include "utilities/globalDefinitions.hpp" 30 31 class LogOutput; 32 class LogDecorators; 33 class LogSelectionList; 34 35 // Global configuration of logging. Handles parsing and configuration of the logging framework, 36 // and manages the list of configured log outputs. The actual tag and level configuration is 37 // kept implicitly in the LogTagSets and their LogOutputLists. During configuration the tagsets 38 // are iterated over and updated accordingly. 39 class LogConfiguration : public AllStatic { 40 friend class VMError; 41 friend class LogTestFixture; 42 public: 43 // Function for listeners 44 typedef void (*UpdateListenerFunction)(void); 45 46 // Register callback for config change. 47 // The callback is always called with ConfigurationLock held, 48 // hence doing log reconfiguration from the callback will deadlock. 49 // The main Java thread may call this callback if there is an early registration 50 // else the attach listener JavaThread, started via diagnostic command, will be executing thread. 51 // The main purpose of this callback is to see if a loglevel have been changed. 52 // There is no way to unregister. 53 static void register_update_listener(UpdateListenerFunction cb); 54 55 private: 56 static LogOutput** _outputs; 57 static size_t _n_outputs; 58 59 static UpdateListenerFunction* _listener_callbacks; 60 static size_t _n_listener_callbacks; 61 62 // Create a new output. Returns NULL if failed. 63 static LogOutput* new_output(const char* name, const char* options, outputStream* errstream); 64 65 // Add an output to the list of configured outputs. Returns the assigned index. 66 static size_t add_output(LogOutput* out); 67 68 // Delete a configured output. The stderr/stdout outputs can not be removed. 69 // Output should be completely disabled before it is deleted. 70 static void delete_output(size_t idx); 71 72 // Disable all logging to the specified output and then delete it (unless it is stdout/stderr). 73 static void disable_output(size_t idx); 74 75 // Get output index by name. Returns SIZE_MAX if output not found. 76 static size_t find_output(const char* name); 77 78 // Configure output (add or update existing configuration) to log on tag-level combination using specified decorators. 79 static void configure_output(size_t idx, const LogSelectionList& tag_level_expression, const LogDecorators& decorators); 80 81 // This should be called after any configuration change while still holding ConfigurationLock 82 static void notify_update_listeners(); 83 84 // Respectively describe the built-in and runtime dependent portions of the configuration. 85 static void describe_available(outputStream* out); 86 static void describe_current_configuration(outputStream* out); 87 88 89 public: 90 // Initialization and finalization of log configuration, to be run at vm startup and shutdown respectively. 91 static void initialize(jlong vm_start_time); 92 static void finalize(); 93 94 // Perform necessary post-initialization after VM startup. Enables reconfiguration of logging. 95 static void post_initialize(); 96 97 // Disable all logging, equivalent to -Xlog:disable. 98 static void disable_logging(); 99 100 // Configures logging on stdout for the given tags and level combination. 101 // Intended for mappings between -XX: flags and Unified Logging configuration. 102 // If exact_match is true, only tagsets with precisely the specified tags will be configured 103 // (exact_match=false is the same as "-Xlog:<tags>*=<level>", and exact_match=true is "-Xlog:<tags>=<level>"). 104 // Tags should be specified using the LOG_TAGS macro, e.g. 105 // LogConfiguration::configure_stdout(LogLevel::<level>, <true/false>, LOG_TAGS(<tags>)); 106 static void configure_stdout(LogLevelType level, int exact_match, ...); 107 108 // Parse command line configuration. Parameter 'opts' is the string immediately following the -Xlog: argument ("gc" for -Xlog:gc). 109 static bool parse_command_line_arguments(const char* opts = "all"); 110 111 // Parse separated configuration arguments (from JCmd/MBean and command line). 112 static bool parse_log_arguments(const char* outputstr, 113 const char* what, 114 const char* decoratorstr, 115 const char* output_options, 116 outputStream* errstream); 117 118 // Prints log configuration to outputStream, used by JCmd/MBean. 119 static void describe(outputStream* out); 120 121 // Prints usage help for command line log configuration. 122 static void print_command_line_help(outputStream* out); 123 124 // Rotates all LogOutput 125 static void rotate_all_outputs(); 126 }; 127 128 #endif // SHARE_LOGGING_LOGCONFIGURATION_HPP 129