add trace command to enable/disable tracing at runtime (#416)

* add trace command to enable/disable tracing at runtime
* rework tracing init/start/stop
* changelog

1 files changed, 49 insertions, 25 deletions

diff --git a/src/zencore/trace.cpp b/src/zencore/trace.cpp
index 6da5d28d6..d71ca0984 100644
--- a/src/zencore/trace.cpp
+++ b/src/zencore/trace.cpp
@@ -9,10 +9,48 @@
 #	include <zencore/trace.h>
 
 void
-TraceInit(const char* HostOrPath, TraceType Type)
+TraceInit()
 {
-	bool EnableEvents = true;
+	static std::atomic_bool gInited	 = false;
+	bool					Expected = false;
+	if (!gInited.compare_exchange_strong(Expected, true))
+	{
+		return;
+	}
+
+	trace::FInitializeDesc Desc = {
+		.bUseImportantCache = true,
+	};
+	trace::Initialize(Desc);
 
+	trace::ThreadRegister("main", /* system id */ 0, /* sort id */ 0);
+	trace::DescribeSession("zenserver",
+#	if ZEN_BUILD_DEBUG
+						   trace::Build::Debug,
+#	else
+						   trace::Build::Development,
+#	endif
+						   "",
+						   ZEN_CFG_VERSION_BUILD_STRING);
+}
+
+void
+TraceShutdown()
+{
+	(void)TraceStop();
+	trace::Shutdown();
+}
+
+bool
+IsTracing()
+{
+	return trace::IsTracing();
+}
+
+void
+TraceStart(const char* HostOrPath, TraceType Type)
+{
+	TraceInit();
 	switch (Type)
 	{
 		case TraceType::Network:
@@ -24,34 +62,20 @@ TraceInit(const char* HostOrPath, TraceType Type)
 			break;
 
 		case TraceType::None:
-			EnableEvents = false;
 			break;
 	}
-
-	trace::FInitializeDesc Desc = {
-		.bUseImportantCache = false,
-	};
-	trace::Initialize(Desc);
-
-	if (EnableEvents)
-	{
-		trace::ToggleChannel("cpu", true);
-		trace::ThreadRegister("main", /* system id */ 0, /* sort id */ 0);
-		trace::DescribeSession("zenserver",
-#	if ZEN_BUILD_DEBUG
-							   trace::Build::Debug,
-#	else
-							   trace::Build::Development,
-#	endif
-							   "",
-							   ZEN_CFG_VERSION_BUILD_STRING);
-	}
+	trace::ToggleChannel("cpu", true);
 }
 
-void
-TraceShutdown()
+bool
+TraceStop()
 {
-	trace::Shutdown();
+	trace::ToggleChannel("cpu", false);
+	if (trace::Stop())
+	{
+		return true;
+	}
+	return false;
 }
 
 #endif	// ZEN_WITH_TRACE