.. _program_listing_file_include_opentelemetry_trace_propagation_global_propagator.h:

Program Listing for File global_propagator.h
============================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_opentelemetry_trace_propagation_global_propagator.h>` (``include/opentelemetry/trace/propagation/global_propagator.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright 2021, OpenTelemetry Authors
   //
   // 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.
   
   #pragma once
   
   #include <mutex>
   
   #include "opentelemetry/trace/propagation/noop_propagator.h"
   #include "opentelemetry/trace/propagation/text_map_propagator.h"
   
   #include "opentelemetry/common/spin_lock_mutex.h"
   #include "opentelemetry/nostd/shared_ptr.h"
   
   #include "opentelemetry/version.h"
   
   OPENTELEMETRY_BEGIN_NAMESPACE
   namespace trace
   {
   namespace propagation
   {
   
   /* Stores the singleton TextMapPropagator */
   
   class GlobalTextMapPropagator
   {
   public:
     static nostd::shared_ptr<TextMapPropagator> GetGlobalPropagator() noexcept
     {
       std::lock_guard<common::SpinLockMutex> guard(GetLock());
       return nostd::shared_ptr<TextMapPropagator>(GetPropagator());
     }
   
     static void SetGlobalPropagator(nostd::shared_ptr<TextMapPropagator> prop) noexcept
     {
       std::lock_guard<common::SpinLockMutex> guard(GetLock());
       GetPropagator() = prop;
     }
   
   private:
     static nostd::shared_ptr<TextMapPropagator> &GetPropagator() noexcept
     {
       static nostd::shared_ptr<TextMapPropagator> propagator(new NoOpPropagator());
       return propagator;
     }
   
     static common::SpinLockMutex &GetLock() noexcept
     {
       static common::SpinLockMutex lock;
       return lock;
     }
   };
   
   }  // namespace propagation
   }  // namespace trace
   OPENTELEMETRY_END_NAMESPACE