update unittest

Author: xiehuc

ext/include/opentelemetry/ext/http/client/curl/http_client_curl.h

@@ -322,7 +322,8 @@ class HttpClient : public opentelemetry::ext::http::client::HttpClient
 
   inline CURLM *GetMultiHandle() noexcept { return multi_handle_; }
 
-  void MaybeSpawnBackgroundThread();
+  // return true if create background thread, false is already exist background thread
+  bool MaybeSpawnBackgroundThread();
 
   void ScheduleAddSession(uint64_t session_id);
   void ScheduleAbortSession(uint64_t session_id);

ext/src/http/client/curl/http_client_curl.cc

@@ -339,12 +339,12 @@ void HttpClient::CleanupSession(uint64_t session_id)
   }
 }
 
-void HttpClient::MaybeSpawnBackgroundThread()
+bool HttpClient::MaybeSpawnBackgroundThread()
 {
   std::lock_guard<std::mutex> lock_guard{background_thread_m_};
   if (background_thread_)
   {
-    return;
+    return false;
   }
 
   background_thread_.reset(new std::thread(
@@ -488,6 +488,7 @@ void HttpClient::MaybeSpawnBackgroundThread()
         }
       },
       this));
+  return true;
 }
 
 void HttpClient::ScheduleAddSession(uint64_t session_id)

ext/test/http/curl_http_test.cc

@@ -1,6 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
+#include <curl/curlver.h>
 #include <gtest/gtest.h>
 #include <string.h>
 #include <atomic>
@@ -11,6 +12,7 @@
 #include <memory>
 #include <mutex>
 #include <string>
+#include <thread>
 #include <utility>
 #include <vector>
 
@@ -547,3 +549,26 @@ TEST_F(BasicCurlHttpTests, ElegantQuitQuick)
   ASSERT_TRUE(handler->is_called_);
   ASSERT_TRUE(handler->got_response_);
 }
+
+TEST_F(BasicCurlHttpTests, BackgroundThreadWaitMore)
+{
+  {
+    curl::HttpClient http_client;
+    http_client.MaybeSpawnBackgroundThread();
+    std::this_thread::sleep_for(std::chrono::milliseconds{10});
+#if LIBCURL_VERSION_NUM >= 0x074200
+    ASSERT_FALSE(http_client.MaybeSpawnBackgroundThread());
+#else
+    // low version curl do not support delay quit, so old background would quit
+    ASSERT_TRUE(http_client.MaybeSpawnBackgroundThread());
+#endif
+  }
+  {
+    curl::HttpClient http_client;
+    http_client.SetBackgroundWaitFor(std::chrono::milliseconds::zero());
+    http_client.MaybeSpawnBackgroundThread();
+    std::this_thread::sleep_for(std::chrono::milliseconds{10});
+    // we can disable delay quit by set wait for 0
+    ASSERT_TRUE(http_client.MaybeSpawnBackgroundThread());
+  }
+}