Introduce YT_DEFINE_GLOBAL to help avoiding initialization order fiasco; apply to global loggers in yt/yt/core

787f98549edf6e8d46ac63cdb8db0609ccde42da

3 files changed, 23 insertions, 1 deletions

diff --git a/library/cpp/yt/logging/logger-inl.h b/library/cpp/yt/logging/logger-inl.h
index d076b3690e..dcf40d9c11 100644
--- a/library/cpp/yt/logging/logger-inl.h
+++ b/library/cpp/yt/logging/logger-inl.h
@@ -64,6 +64,11 @@ Y_FORCE_INLINE bool TLogger::IsLevelEnabled(ELogLevel level) const
     return IsLevelEnabledHeavy(level);
 }
 
+Y_FORCE_INLINE const TLogger& TLogger::operator()() const
+{
+    return *this;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 namespace NDetail {
diff --git a/library/cpp/yt/logging/logger.h b/library/cpp/yt/logging/logger.h
index 0913b9ea08..693ea2b9cd 100644
--- a/library/cpp/yt/logging/logger.h
+++ b/library/cpp/yt/logging/logger.h
@@ -181,6 +181,10 @@ public:
 
     explicit operator bool() const;
 
+    //! Enables using |Logger| in YT_LOG_* macros as both data members and functions
+    //! (e.g. those introduced by YT_DEFINE_GLOBAL).
+    const TLogger& operator()() const;
+
     const TLoggingCategory* GetCategory() const;
 
     //! Validate that level is admitted by logger's own min level
@@ -292,7 +296,7 @@ void LogStructuredEvent(
 
 #define YT_LOG_EVENT_WITH_ANCHOR(logger, level, anchor, ...) \
     do { \
-        const auto& logger__ = (logger); \
+        const auto& logger__ = (logger)(); \
         auto level__ = (level); \
         \
         if (!logger__.IsLevelEnabled(level__)) { \
diff --git a/library/cpp/yt/misc/global.h b/library/cpp/yt/misc/global.h
new file mode 100644
index 0000000000..df831b50c3
--- /dev/null
+++ b/library/cpp/yt/misc/global.h
@@ -0,0 +1,13 @@
+#pragma once
+
+//! Defines a global variable that is initialized on its first access.
+/*!
+ *  In contrast to a usual variable with static storage duration, this one
+ *  is not susceptible to initialization order fisco issues.
+ */
+#define YT_DEFINE_GLOBAL(type, name, ...) \
+    inline type& name() \
+    { \
+        static type result(__VA_ARGS__); \
+        return result;  \
+    }