1 files changed, 38 insertions, 0 deletions
diff --git a/fcp/tracing/tracing_span_impl.cc b/fcp/tracing/tracing_span_impl.cc
new file mode 100644
index 0000000..6c1b20d
--- /dev/null
+++ b/fcp/tracing/tracing_span_impl.cc
@@ -0,0 +1,38 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "fcp/tracing/tracing_span_impl.h"
+
+#include "fcp/tracing/tracing_recorder_impl.h"
+
+namespace fcp {
+namespace tracing_internal {
+
+thread_local TracingSpanImpl* TracingSpanImpl::top_tracing_span_ = nullptr;
+
+TracingSpanImpl* TracingSpanImpl::Top() { return top_tracing_span_; }
+
+void TracingSpanImpl::Pop() {
+  FCP_CHECK(top_tracing_span_ == this);
+  top_tracing_span_ = prev_;
+}
+
+void TracingSpanImpl::Push() {
+  FCP_CHECK(prev_ == nullptr);
+  prev_ = top_tracing_span_;
+  top_tracing_span_ = this;
+}
+
+}  // namespace tracing_internal
+}  // namespace fcp