Pre-initialization of default logger (#859)

Improved workaround for troubles with code potentially logging before logging is initialized. Any logging will be routed to a default console logger until logging is initialized fully

4 files changed, 30 insertions, 6 deletions

diff --git a/src/zencore/include/zencore/logbase.h b/src/zencore/include/zencore/logbase.h
index 046e96db3..ad2ab218d 100644
--- a/src/zencore/include/zencore/logbase.h
+++ b/src/zencore/include/zencore/logbase.h
@@ -101,7 +101,7 @@ struct LoggerRef
 	inline logging::Logger* operator->() const;
 	inline logging::Logger& operator*() const;
 
-	bool			  ShouldLog(logging::LogLevel Level) const { return m_Logger && m_Logger->ShouldLog(Level); }
+	bool			  ShouldLog(logging::LogLevel Level) const { return m_Logger->ShouldLog(Level); }
 	void			  SetLogLevel(logging::LogLevel NewLogLevel) { m_Logger->SetLevel(NewLogLevel); }
 	logging::LogLevel GetLogLevel() { return m_Logger->GetLevel(); }
 
diff --git a/src/zencore/include/zencore/logging.h b/src/zencore/include/zencore/logging.h
index dc5e05656..3427991d2 100644
--- a/src/zencore/include/zencore/logging.h
+++ b/src/zencore/include/zencore/logging.h
@@ -18,6 +18,7 @@ namespace zen::logging {
 
 void InitializeLogging();
 void ShutdownLogging();
+bool IsLoggingInitialized();
 bool EnableVTMode();
 void FlushLogging();
 
diff --git a/src/zencore/logging.cpp b/src/zencore/logging.cpp
index 900da6c6d..3206e380b 100644
--- a/src/zencore/logging.cpp
+++ b/src/zencore/logging.cpp
@@ -21,14 +21,35 @@
 #	pragma section(".zlog$z", read)
 #endif
 
+namespace {
+
+// Bootstrap logger: a minimal stdout logger that exists for the entire lifetime
+// of the process.  TheDefaultLogger points here before InitializeLogging() runs
+// (and is restored here after ShutdownLogging()) so that log macros always have
+// a usable target — no null checks or lazy init required on the common path.
+zen::Ref<zen::logging::Logger> s_BootstrapLogger = [] {
+	zen::logging::SinkPtr Sink(new zen::logging::AnsiColorStdoutSink());
+	return zen::Ref<zen::logging::Logger>(new zen::logging::Logger("", Sink));
+}();
+
+}  // namespace
+
 namespace zen {
 
-LoggerRef TheDefaultLogger;
+LoggerRef TheDefaultLogger{*s_BootstrapLogger};
 
 }  // namespace zen
 
 namespace zen::logging {
 
+static bool g_LoggingInitialized = false;
+
+bool
+IsLoggingInitialized()
+{
+	return g_LoggingInitialized;
+}
+
 //////////////////////////////////////////////////////////////////////////
 
 LoggerRef
@@ -232,7 +253,7 @@ GetLogLevel()
 LoggerRef
 Default()
 {
-	ZEN_ASSERT(TheDefaultLogger, "logging::InitializeLogging() must be called before using the logger");
+	ZEN_ASSERT(g_LoggingInitialized, "logging::InitializeLogging() must be called before using the logger");
 	return TheDefaultLogger;
 }
 
@@ -393,7 +414,8 @@ InitializeLogging()
 {
 	ZEN_MEMSCOPE(ELLMTag::Logging);
 
-	TheDefaultLogger = LoggerRef(*Registry::Instance().DefaultLoggerRaw());
+	TheDefaultLogger	 = LoggerRef(*Registry::Instance().DefaultLoggerRaw());
+	g_LoggingInitialized = true;
 }
 
 void
@@ -401,8 +423,9 @@ ShutdownLogging()
 {
 	ZEN_MEMSCOPE(ELLMTag::Logging);
 
+	g_LoggingInitialized = false;
 	Registry::Instance().Shutdown();
-	TheDefaultLogger = {};
+	TheDefaultLogger = LoggerRef(*s_BootstrapLogger);
 }
 
 bool
diff --git a/src/zencore/sentryintegration.cpp b/src/zencore/sentryintegration.cpp
index 634045cfb..c9c843dd6 100644
--- a/src/zencore/sentryintegration.cpp
+++ b/src/zencore/sentryintegration.cpp
@@ -160,7 +160,7 @@ SentryLogFunction(sentry_level_t Level, const char* Message, va_list Args, [[may
 	// been configured, we ignore the callbacks for DEBUG/INFO explicitly here
 	// which means users don't see every possible log message if they're trying
 	// to configure the levels using --log-debug=sentry-sdk
-	if (!TheDefaultLogger || !s_SentryLogEnabled.load(std::memory_order_acquire))
+	if (!zen::logging::IsLoggingInitialized() || !s_SentryLogEnabled.load(std::memory_order_acquire))
 	{
 		switch (Level)
 		{