src: nullcheck on trace controller

Insert a NULLCHECK prior to return. Ideally we do this in the caller, but the TraceController object is somewhat special as: 1. It is accessed by most threads 2. It's life cycle is managed by Agent::Agent 3. It's getter is invoked through Base Methods (upstream) Refs: nodejs#25814 PR-URL: nodejs#25943 Reviewed-By: James M Snell <[email protected]> Reviewed-By: Masashi Hirano <[email protected]> Reviewed-By: Richard Lau <[email protected]> Reviewed-By: Anna Henningsen <[email protected]>
Rachelmorrell · Feb 8, 2019 · c70e853 · c70e853
1 parent 3a4521a
commit c70e853
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Showing 3 changed files with 6 additions and 5 deletions.
diff --git a/src/env.cc b/src/env.cc
@@ -208,8 +208,7 @@ Environment::Environment(IsolateData* isolate_data,
   if (tracing::AgentWriterHandle* writer = GetTracingAgentWriter()) {
     trace_state_observer_ = std::make_unique<TrackingTraceStateObserver>(this);
     TracingController* tracing_controller = writer->GetTracingController();
-    if (tracing_controller != nullptr)
-      tracing_controller->AddTraceStateObserver(trace_state_observer_.get());
+    tracing_controller->AddTraceStateObserver(trace_state_observer_.get());
   }
 
   destroy_async_id_list_.reserve(512);
@@ -272,8 +271,7 @@ Environment::~Environment() {
     tracing::AgentWriterHandle* writer = GetTracingAgentWriter();
     CHECK_NOT_NULL(writer);
     TracingController* tracing_controller = writer->GetTracingController();
-    if (tracing_controller != nullptr)
-      tracing_controller->RemoveTraceStateObserver(trace_state_observer_.get());
+    tracing_controller->RemoveTraceStateObserver(trace_state_observer_.get());
   }
 
   delete[] heap_statistics_buffer_;

diff --git a/src/node_platform.cc b/src/node_platform.cc
@@ -459,6 +459,7 @@ double NodePlatform::CurrentClockTimeMillis() {
 }
 
 TracingController* NodePlatform::GetTracingController() {
+  CHECK_NOT_NULL(tracing_controller_);
   return tracing_controller_;
 }
 

diff --git a/src/tracing/agent.h b/src/tracing/agent.h
@@ -81,7 +81,9 @@ class Agent {
   ~Agent();
 
   TracingController* GetTracingController() {
-    return tracing_controller_.get();
+    TracingController* controller = tracing_controller_.get();
+    CHECK_NOT_NULL(controller);
+    return controller;
   }
 
   enum UseDefaultCategoryMode {