1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
31class LogOutput;
32class LogDecorators;
33class 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.
39class 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