src/hotspot/share/logging/log.hpp
changeset 47216 71c04702a3d5
parent 46701 f559541c0daa
child 49364 601146c66cad
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/logging/log.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,202 @@
+/*
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+#ifndef SHARE_VM_LOGGING_LOG_HPP
+#define SHARE_VM_LOGGING_LOG_HPP
+
+#include "logging/logLevel.hpp"
+#include "logging/logPrefix.hpp"
+#include "logging/logTagSet.hpp"
+#include "logging/logTag.hpp"
+#include "memory/allocation.hpp"
+#include "runtime/os.hpp"
+#include "utilities/debug.hpp"
+
+class LogMessageBuffer;
+
+//
+// Logging macros
+//
+// Usage:
+//   log_<level>(<comma separated log tags>)(<printf-style log arguments>);
+// e.g.
+//   log_debug(logging)("message %d", i);
+//
+// Note that these macros will not evaluate the arguments unless the logging is enabled.
+//
+#define log_error(...)   (!log_is_enabled(Error, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Error>
+#define log_warning(...) (!log_is_enabled(Warning, __VA_ARGS__)) ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Warning>
+#define log_info(...)    (!log_is_enabled(Info, __VA_ARGS__))    ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Info>
+#define log_debug(...)   (!log_is_enabled(Debug, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Debug>
+#define log_trace(...)   (!log_is_enabled(Trace, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Trace>
+
+// Macros for logging that should be excluded in product builds.
+// Available for levels Info, Debug and Trace. Includes test macro that
+// evaluates to false in product builds.
+#ifndef PRODUCT
+#define log_develop_info(...)  (!log_is_enabled(Info, __VA_ARGS__))   ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Info>
+#define log_develop_debug(...) (!log_is_enabled(Debug, __VA_ARGS__)) ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Debug>
+#define log_develop_trace(...) (!log_is_enabled(Trace, __VA_ARGS__))  ? (void)0 : LogImpl<LOG_TAGS(__VA_ARGS__)>::write<LogLevel::Trace>
+#define log_develop_is_enabled(level, ...)  log_is_enabled(level, __VA_ARGS__)
+#else
+#define DUMMY_ARGUMENT_CONSUMER(...)
+#define log_develop_info(...)  DUMMY_ARGUMENT_CONSUMER
+#define log_develop_debug(...) DUMMY_ARGUMENT_CONSUMER
+#define log_develop_trace(...) DUMMY_ARGUMENT_CONSUMER
+#define log_develop_is_enabled(...)  false
+#endif
+
+// Convenience macro to test if the logging is enabled on the specified level for given tags.
+#define log_is_enabled(level, ...) (LogImpl<LOG_TAGS(__VA_ARGS__)>::is_level(LogLevel::level))
+
+//
+// Log class for more advanced logging scenarios.
+// Has printf-style member functions for each log level (trace(), debug(), etc).
+//
+// Also has outputStream compatible API for the different log-levels.
+// The streams are resource allocated when requested and are accessed through
+// calls to <level>_stream() functions (trace_stream(), debug_stream(), etc).
+//
+// Example usage:
+//   Log(logging) log;
+//   if (log.is_debug()) {
+//     ...
+//     log.debug("result = %d", result).trace(" tracing info");
+//     obj->print_on(log.debug_stream());
+//   }
+//
+#define Log(...)  LogImpl<LOG_TAGS(__VA_ARGS__)>
+
+//
+// Log class that embeds both log tags and a log level.
+//
+// The class provides a way to write the tags and log level once,
+// so that redundant specification of tags or levels can be avoided.
+//
+// Example usage:
+//   LogTarget(Debug, gc) out;
+//   if (out.is_enabled()) {
+//     ...
+//     out.print("Worker: %u", i);
+//     out.print(" data: %d", x);
+//     ...
+//     print_stats(out.stream());
+//   }
+//
+#define LogTarget(level, ...) LogTargetImpl<LogLevel::level, LOG_TAGS(__VA_ARGS__)>
+
+template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
+class LogTargetImpl;
+
+template <LogTagType T0, LogTagType T1 = LogTag::__NO_TAG, LogTagType T2 = LogTag::__NO_TAG, LogTagType T3 = LogTag::__NO_TAG,
+          LogTagType T4 = LogTag::__NO_TAG, LogTagType GuardTag = LogTag::__NO_TAG>
+class LogImpl VALUE_OBJ_CLASS_SPEC {
+ private:
+  static const size_t LogBufferSize = 512;
+ public:
+  // Make sure no more than the maximum number of tags have been given.
+  // The GuardTag allows this to be detected if/when it happens. If the GuardTag
+  // is not __NO_TAG, the number of tags given exceeds the maximum allowed.
+  STATIC_ASSERT(GuardTag == LogTag::__NO_TAG); // Number of logging tags exceeds maximum supported!
+
+  // Empty constructor to avoid warnings on MSVC about unused variables
+  // when the log instance is only used for static functions.
+  LogImpl() {
+  }
+
+  static bool is_level(LogLevelType level) {
+    return LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().is_level(level);
+  }
+
+  ATTRIBUTE_PRINTF(2, 3)
+  static void write(LogLevelType level, const char* fmt, ...) {
+    va_list args;
+    va_start(args, fmt);
+    vwrite(level, fmt, args);
+    va_end(args);
+  }
+
+  static void write(const LogMessageBuffer& msg) {
+    LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().log(msg);
+  };
+
+  template <LogLevelType Level>
+  ATTRIBUTE_PRINTF(1, 2)
+  static void write(const char* fmt, ...) {
+    va_list args;
+    va_start(args, fmt);
+    vwrite(Level, fmt, args);
+    va_end(args);
+  }
+
+  ATTRIBUTE_PRINTF(2, 0)
+  static void vwrite(LogLevelType level, const char* fmt, va_list args) {
+    LogTagSetMapping<T0, T1, T2, T3, T4>::tagset().vwrite(level, fmt, args);
+  }
+
+#define LOG_LEVEL(level, name) ATTRIBUTE_PRINTF(2, 0) \
+  LogImpl& v##name(const char* fmt, va_list args) { \
+    vwrite(LogLevel::level, fmt, args); \
+    return *this; \
+  } \
+  LogImpl& name(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3) { \
+    va_list args; \
+    va_start(args, fmt); \
+    vwrite(LogLevel::level, fmt, args); \
+    va_end(args); \
+    return *this; \
+  } \
+  static bool is_##name() { \
+    return is_level(LogLevel::level); \
+  } \
+  static LogTargetImpl<LogLevel::level, T0, T1, T2, T3, T4, GuardTag>* name() { \
+    return (LogTargetImpl<LogLevel::level, T0, T1, T2, T3, T4, GuardTag>*)NULL; \
+  }
+  LOG_LEVEL_LIST
+#undef LOG_LEVEL
+};
+
+// Combines logging tags and a logging level.
+template <LogLevelType level, LogTagType T0, LogTagType T1 = LogTag::__NO_TAG, LogTagType T2 = LogTag::__NO_TAG,
+          LogTagType T3 = LogTag::__NO_TAG, LogTagType T4 = LogTag::__NO_TAG, LogTagType GuardTag = LogTag::__NO_TAG>
+class LogTargetImpl {
+public:
+  // Empty constructor to avoid warnings on MSVC about unused variables
+  // when the log instance is only used for static functions.
+  LogTargetImpl() {
+  }
+
+  static bool is_enabled() {
+    return LogImpl<T0, T1, T2, T3, T4, GuardTag>::is_level(level);
+  }
+
+  static void print(const char* fmt, ...) ATTRIBUTE_PRINTF(1, 2) {
+    va_list args;
+    va_start(args, fmt);
+    LogImpl<T0, T1, T2, T3, T4, GuardTag>::vwrite(level, fmt, args);
+    va_end(args);
+  }
+
+};
+
+#endif // SHARE_VM_LOGGING_LOG_HPP