1/*
2 * Copyright (c) 2015, 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_LOG_HPP
25#define SHARE_VM_LOGGING_LOG_HPP
26
27#include "logging/logLevel.hpp"
28#include "logging/logPrefix.hpp"
29#include "logging/logTagSet.hpp"
30#include "logging/logTag.hpp"
31#include "memory/allocation.hpp"
32#include "runtime/os.hpp"
33#include "utilities/debug.hpp"
34
35class LogMessageBuffer;
36
37//
38// Logging macros
39//
40// Usage:
41//   log_<level>(<comma separated log tags>)(<printf-style log arguments>);
42// e.g.
43//   log_debug(logging)("message %d", i);
44//
45// Note that these macros will not evaluate the arguments unless the logging is enabled.
46//
47#define log_error(...)   (!log_is_enabled(Error, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Error>
48#define log_warning(...) (!log_is_enabled(Warning, __VA_ARGS__)) ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Warning>
49#define log_info(...)    (!log_is_enabled(Info, __VA_ARGS__))    ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Info>
50#define log_debug(...)   (!log_is_enabled(Debug, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Debug>
51#define log_trace(...)   (!log_is_enabled(Trace, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Trace>
52
53// Macros for logging that should be excluded in product builds.
54// Available for levels Info, Debug and Trace. Includes test macro that
55// evaluates to false in product builds.
56#ifndef PRODUCT
57#define log_develop_info(...)  (!log_is_enabled(Info, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Info>
58#define log_develop_debug(...) (!log_is_enabled(Debug, __VA_ARGS__)) ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Debug>
59#define log_develop_trace(...) (!log_is_enabled(Trace, __VA_ARGS__))  ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Trace>
60#define log_develop_is_enabled(level, ...)  log_is_enabled(level, __VA_ARGS__)
61#else
62#define DUMMY_ARGUMENT_CONSUMER(...)
63#define log_develop_info(...)  DUMMY_ARGUMENT_CONSUMER
64#define log_develop_debug(...) DUMMY_ARGUMENT_CONSUMER
65#define log_develop_trace(...) DUMMY_ARGUMENT_CONSUMER
66#define log_develop_is_enabled(...)  false
67#endif
68
69// Convenience macro to test if the logging is enabled on the specified level for given tags.
70#define log_is_enabled(level, ...) (LogImpl<LOG_TAGS(__VA_ARGS__)>::is_level(LogLevel::level))
71
72//
73// Log class for more advanced logging scenarios.
74// Has printf-style member functions for each log level (trace(), debug(), etc).
75//
76// Also has outputStream compatible API for the different log-levels.
77// The streams are resource allocated when requested and are accessed through
78// calls to <level>_stream() functions (trace_stream(), debug_stream(), etc).
79//
80// Example usage:
81//   Log(logging) log;
82//   if (log.is_debug()) {
83//     ...
84//     log.debug("result = %d", result).trace(" tracing info");
85//     obj->print_on(log.debug_stream());
86//   }
87//
88#define Log(...)  LogImpl<LOG_TAGS(__VA_ARGS__)>
89
90//
91// Log class that embeds both log tags and a log level.
92//
93// The class provides a way to write the tags and log level once,
94// so that redundant specification of tags or levels can be avoided.
95//
96// Example usage:
97//   LogTarget(Debug, gc) out;
98//   if (out.is_enabled()) {
99//     ...
100//     out.print("Worker: %u", i);
101//     out.print(" data: %d", x);
102//     ...
103//     print_stats(out.stream());
104//   }
105//
106#define LogTarget(level, ...) LogTargetImpl<LogLevel::level, LOG_TAGS(__VA_ARGS__)>
107
108// Forward declaration to decouple this file from the outputStream API.
109class outputStream;
110outputStream* create_log_stream(LogLevelType level, LogTagSet* tagset);
111
112template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
113class LogTargetImpl;
114
115template <LogTagType T0, LogTagType T1 = LogTag::__NO_TAG, LogTagType T2 = LogTag::__NO_TAG, LogTagType T3 = LogTag::__NO_TAG,
116          LogTagType T4 = LogTag::__NO_TAG, LogTagType GuardTag = LogTag::__NO_TAG>
117class LogImpl VALUE_OBJ_CLASS_SPEC {
118 private:
119  static const size_t LogBufferSize = 512;
120 public:
121  // Make sure no more than the maximum number of tags have been given.
122  // The GuardTag allows this to be detected if/when it happens. If the GuardTag
123  // is not __NO_TAG, the number of tags given exceeds the maximum allowed.
124  STATIC_ASSERT(GuardTag == LogTag::__NO_TAG); // Number of logging tags exceeds maximum supported!
125
126  // Empty constructor to avoid warnings on MSVC about unused variables
127  // when the log instance is only used for static functions.
128  LogImpl() {
129  }
130
131  static bool is_level(LogLevelType level) {
132    return LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().is_level(level);
133  }
134
135  ATTRIBUTE_PRINTF(2, 3)
136  static void write(LogLevelType level, const char* fmt, ...) {
137    va_list args;
138    va_start(args, fmt);
139    vwrite(level, fmt, args);
140    va_end(args);
141  }
142
143  static void write(const LogMessageBuffer& msg) {
144    LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().log(msg);
145  };
146
147  template <LogLevelType Level>
148  ATTRIBUTE_PRINTF(1, 2)
149  static void write(const char* fmt, ...) {
150    va_list args;
151    va_start(args, fmt);
152    vwrite(Level, fmt, args);
153    va_end(args);
154  }
155
156  ATTRIBUTE_PRINTF(2, 0)
157  static void vwrite(LogLevelType level, const char* fmt, va_list args) {
158    LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().vwrite(level, fmt, args);
159  }
160
161#define LOG_LEVEL(level, name) ATTRIBUTE_PRINTF(2, 0) \
162  LogImpl& v##name(const char* fmt, va_list args) { \
163    vwrite(LogLevel::level, fmt, args); \
164    return *this; \
165  } \
166  LogImpl& name(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3) { \
167    va_list args; \
168    va_start(args, fmt); \
169    vwrite(LogLevel::level, fmt, args); \
170    va_end(args); \
171    return *this; \
172  } \
173  static bool is_##name() { \
174    return is_level(LogLevel::level); \
175  } \
176  static outputStream* name##_stream() { \
177    return create_log_stream(LogLevel::level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()); \
178  } \
179  static LogTargetImpl<LogLevel::level, T0, T1, T2, T3, T4, GuardTag>* name() { \
180    return (LogTargetImpl<LogLevel::level, T0, T1, T2, T3, T4, GuardTag>*)NULL; \
181  }
182  LOG_LEVEL_LIST
183#undef LOG_LEVEL
184};
185
186// Combines logging tags and a logging level.
187template <LogLevelType level, LogTagType T0, LogTagType T1 = LogTag::__NO_TAG, LogTagType T2 = LogTag::__NO_TAG,
188          LogTagType T3 = LogTag::__NO_TAG, LogTagType T4 = LogTag::__NO_TAG, LogTagType GuardTag = LogTag::__NO_TAG>
189class LogTargetImpl {
190public:
191  // Empty constructor to avoid warnings on MSVC about unused variables
192  // when the log instance is only used for static functions.
193  LogTargetImpl() {
194  }
195
196  static bool is_enabled() {
197    return LogImpl<T0, T1, T2, T3, T4, GuardTag>::is_level(level);
198  }
199
200  static void print(const char* fmt, ...) ATTRIBUTE_PRINTF(1, 2) {
201    va_list args;
202    va_start(args, fmt);
203    LogImpl<T0, T1, T2, T3, T4, GuardTag>::vwrite(level, fmt, args);
204    va_end(args);
205  }
206
207  static outputStream* stream() {
208    return create_log_stream(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset());
209  }
210};
211
212#endif // SHARE_VM_LOGGING_LOG_HPP
213