From d6936b6bee465f903a5788dd2c76bbd49f8cb48b Mon Sep 17 00:00:00 2001
From: David Garcia Quintas <dgq@google.com>
Date: Tue, 29 Nov 2016 17:22:48 -0800
Subject: [PATCH] PR comments

---
 test/cpp/qps/json_run_localhost.cc | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/test/cpp/qps/json_run_localhost.cc b/test/cpp/qps/json_run_localhost.cc
index 70c50cdc71b..59a5a89ca34 100644
--- a/test/cpp/qps/json_run_localhost.cc
+++ b/test/cpp/qps/json_run_localhost.cc
@@ -47,8 +47,9 @@
 
 using grpc::SubProcess;
 typedef std::unique_ptr<SubProcess> SubProcessPtr;
-std::vector<SubProcessPtr> g_workers;
 SubProcessPtr g_driver;
+constexpr auto kNumWorkers = 2;
+std::vector<SubProcessPtr> g_workers(2);
 
 template <class T>
 std::string as_string(const T& val) {
@@ -58,10 +59,11 @@ std::string as_string(const T& val) {
 }
 
 static void sighandler(int sig) {
+  const int errno_saved = errno;
   g_driver->Interrupt();
-  for (auto it = g_workers.begin(); it != g_workers.end(); ++it) {
-    (*it)->Interrupt();
-  }
+  for (const auto& worker : g_workers)
+    if (worker) worker->Interrupt();
+  errno = errno_saved;
 }
 
 static void register_sighandler() {
@@ -82,11 +84,11 @@ int main(int argc, char** argv) {
   std::ostringstream env;
   bool first = true;
 
-  for (int i = 0; i < 2; i++) {
-    auto port = grpc_pick_unused_port_or_die();
+  for (int i = 0; i < kNumWorkers; i++) {
+    const auto port = grpc_pick_unused_port_or_die();
     std::vector<std::string> args = {bin_dir + "/qps_worker", "-driver_port",
                                      as_string(port)};
-    g_workers.emplace_back(new SubProcess(args));
+    g_workers[i].reset(new SubProcess(args));
     if (!first) env << ",";
     env << "localhost:" << port;
     first = false;
@@ -100,11 +102,9 @@ int main(int argc, char** argv) {
 
   g_driver.reset(new SubProcess(args));
   const int driver_join_status = g_driver->Join();
-  for (auto it = g_workers.begin(); it != g_workers.end(); ++it) {
-    (*it)->Interrupt();
-  }
-  for (auto it = g_workers.begin(); it != g_workers.end(); ++it) {
-    (*it)->Join();
-  }
+  for (const auto& worker : g_workers)
+    if (worker) worker->Interrupt();
+  for (const auto& worker : g_workers)
+    if (worker) worker->Join();
   GPR_ASSERT(driver_join_status == 0);
 }