From d20706b04ea479638a22636ea08d805c8d218a04 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 24 Jun 2022 19:55:10 +0000
Subject: [PATCH 01/17] Only call ares_library_init()/cleanup() routines in
 process_wide() if ares extension is linked in.

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                       |  2 ++
 source/exe/BUILD                                   |  1 +
 source/exe/process_wide.cc                         | 14 ++++++++++++--
 .../network/dns_resolver/cares/dns_impl.cc         |  3 +++
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index 2a326f152fe83..e498614c3f8ec 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -26,6 +26,8 @@ class DnsResolverFactory : public Config::TypedFactory {
       const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) const PURE;
 
   std::string category() const override { return std::string(DnsResolverCategory); }
+  virtual void init() {}
+  virtual void cleanup() {}
 };
 
 } // namespace Network
diff --git a/source/exe/BUILD b/source/exe/BUILD
index 994bc24231636..cf2b9462e6aca 100644
--- a/source/exe/BUILD
+++ b/source/exe/BUILD
@@ -143,6 +143,7 @@ envoy_cc_library(
     hdrs = ["process_wide.h"],
     external_deps = ["ares"],
     deps = [
+        "//envoy/network:dns_resolver_interface",
         "//source/common/common:assert_lib",
         "//source/common/event:libevent_lib",
         "//source/common/http/http2:nghttp2_lib",
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index df421084a21b1..a0a66fd30c990 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -1,5 +1,6 @@
 #include "source/exe/process_wide.h"
 
+#include "envoy/network/dns_resolver.h"
 #include "source/common/common/assert.h"
 #include "source/common/event/libevent.h"
 #include "source/common/http/http2/nghttp2.h"
@@ -30,7 +31,12 @@ ProcessWide::ProcessWide() {
   if (init_data.count_++ == 0) {
     // TODO(mattklein123): Audit the following as not all of these have to be re-initialized in the
     // edge case where something does init/destroy/init/destroy.
-    ares_library_init(ARES_LIB_INIT_ALL);
+
+    // Initialize c-ares library if it is linked in.
+    if  (auto* dns_factory = Config::Utility::getAndCheckFactoryByName
+         <Network::DnsResolverFactory>(std::string(Network::CaresDnsResolver), true)) {
+      dns_factory->init();
+    }
     Event::Libevent::Global::initialize();
     Envoy::Server::validateProtoDescriptors();
     Http::Http2::initializeNghttp2Logging();
@@ -58,7 +64,11 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    ares_library_cleanup();
+    // Cleanup c-ares library if it is linked in.
+    if  (auto* dns_factory = Config::Utility::getAndCheckFactoryByName
+         <Network::DnsResolverFactory>(std::string(Network::CaresDnsResolver), true)) {
+      dns_factory->cleanup();
+    }
   }
 }
 
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index 35c147083be25..de0745c129c5c 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -521,6 +521,9 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     }
     return std::make_shared<Network::DnsResolverImpl>(cares, dispatcher, resolvers);
   }
+
+  void init() override { ares_library_init(ARES_LIB_INIT_ALL); }
+  void cleanup() override { ares_library_cleanup(); }
 };
 
 // Register the CaresDnsResolverFactory

From f9751b7b15ba147bc5a26ed652745dc82fed4274 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Sat, 25 Jun 2022 12:19:34 +0000
Subject: [PATCH 02/17]  remove ares dependancy from process_wide

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/exe/BUILD           | 1 -
 source/exe/process_wide.cc | 2 --
 2 files changed, 3 deletions(-)

diff --git a/source/exe/BUILD b/source/exe/BUILD
index cf2b9462e6aca..7059a446017ff 100644
--- a/source/exe/BUILD
+++ b/source/exe/BUILD
@@ -141,7 +141,6 @@ envoy_cc_library(
     name = "process_wide_lib",
     srcs = ["process_wide.cc"],
     hdrs = ["process_wide.h"],
-    external_deps = ["ares"],
     deps = [
         "//envoy/network:dns_resolver_interface",
         "//source/common/common:assert_lib",
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index a0a66fd30c990..d55bc8edbf7fd 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -6,8 +6,6 @@
 #include "source/common/http/http2/nghttp2.h"
 #include "source/server/proto_descriptors.h"
 
-#include "ares.h"
-
 namespace Envoy {
 namespace {
 

From c4aaa4bb05ce9d4bea1437a87d77d0c04b3a72b9 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Sun, 26 Jun 2022 16:22:40 +0000
Subject: [PATCH 03/17]  fix format error

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/exe/process_wide.cc | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index d55bc8edbf7fd..343644a8e4eb5 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -1,6 +1,7 @@
 #include "source/exe/process_wide.h"
 
 #include "envoy/network/dns_resolver.h"
+
 #include "source/common/common/assert.h"
 #include "source/common/event/libevent.h"
 #include "source/common/http/http2/nghttp2.h"
@@ -31,8 +32,8 @@ ProcessWide::ProcessWide() {
     // edge case where something does init/destroy/init/destroy.
 
     // Initialize c-ares library if it is linked in.
-    if  (auto* dns_factory = Config::Utility::getAndCheckFactoryByName
-         <Network::DnsResolverFactory>(std::string(Network::CaresDnsResolver), true)) {
+    if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
+            std::string(Network::CaresDnsResolver), true)) {
       dns_factory->init();
     }
     Event::Libevent::Global::initialize();
@@ -63,8 +64,8 @@ ProcessWide::~ProcessWide() {
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
     // Cleanup c-ares library if it is linked in.
-    if  (auto* dns_factory = Config::Utility::getAndCheckFactoryByName
-         <Network::DnsResolverFactory>(std::string(Network::CaresDnsResolver), true)) {
+    if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
+            std::string(Network::CaresDnsResolver), true)) {
       dns_factory->cleanup();
     }
   }

From 95d221628db253d4a05371439e122286587ae062 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Sun, 26 Jun 2022 17:01:08 +0000
Subject: [PATCH 04/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                    |  1 -
 source/exe/process_wide.cc                      |  6 ------
 .../network/dns_resolver/cares/dns_impl.cc      | 17 +++++++++++++++--
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index e498614c3f8ec..f9ad71a79cf1e 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -26,7 +26,6 @@ class DnsResolverFactory : public Config::TypedFactory {
       const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) const PURE;
 
   std::string category() const override { return std::string(DnsResolverCategory); }
-  virtual void init() {}
   virtual void cleanup() {}
 };
 
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index 343644a8e4eb5..082e30f9b9802 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -30,12 +30,6 @@ ProcessWide::ProcessWide() {
   if (init_data.count_++ == 0) {
     // TODO(mattklein123): Audit the following as not all of these have to be re-initialized in the
     // edge case where something does init/destroy/init/destroy.
-
-    // Initialize c-ares library if it is linked in.
-    if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
-            std::string(Network::CaresDnsResolver), true)) {
-      dns_factory->init();
-    }
     Event::Libevent::Global::initialize();
     Envoy::Server::validateProtoDescriptors();
     Http::Http2::initializeNghttp2Logging();
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index de0745c129c5c..5289ad08c9c16 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -495,6 +495,7 @@ DnsResolverImpl::AddrInfoPendingResolution::availableInterfaces() {
 // c-ares DNS resolver factory
 class CaresDnsResolverFactory : public DnsResolverFactory {
 public:
+  CaresDnsResolverFactory() : ares_library_initialized_(false) {}
   std::string name() const override { return std::string(CaresDnsResolver); }
 
   ProtobufTypes::MessagePtr createEmptyConfigProto() override {
@@ -507,6 +508,11 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
                                              typed_dns_resolver_config) const override {
     envoy::extensions::network::dns_resolver::cares::v3::CaresDnsResolverConfig cares;
     std::vector<Network::Address::InstanceConstSharedPtr> resolvers;
+    // Initialize c-ares library in case first time.
+    if (!ares_library_initialized_) {
+      ares_library_init(ARES_LIB_INIT_ALL);
+      ares_library_initialized_ = true;
+    }
 
     ASSERT(dispatcher.isThreadSafe());
     // Only c-ares DNS factory will call into this function.
@@ -522,8 +528,15 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     return std::make_shared<Network::DnsResolverImpl>(cares, dispatcher, resolvers);
   }
 
-  void init() override { ares_library_init(ARES_LIB_INIT_ALL); }
-  void cleanup() override { ares_library_cleanup(); }
+  void cleanup() override {
+    // Cleanup c-ares library if initialized.
+    if (ares_library_initialized_) {
+      ares_library_cleanup();
+    }
+  }
+
+private:
+  mutable bool ares_library_initialized_;
 };
 
 // Register the CaresDnsResolverFactory

From d425d911eb940d16c34f6c5f987714eed20ce619 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Sun, 26 Jun 2022 19:36:23 +0000
Subject: [PATCH 05/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                         |  1 +
 .../common/network/dns_resolver/dns_factory_util.cc  |  7 +++++--
 .../network/dns_resolver/cares/dns_impl.cc           | 12 +++++++-----
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index f9ad71a79cf1e..e498614c3f8ec 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -26,6 +26,7 @@ class DnsResolverFactory : public Config::TypedFactory {
       const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) const PURE;
 
   std::string category() const override { return std::string(DnsResolverCategory); }
+  virtual void init() {}
   virtual void cleanup() {}
 };
 
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index d8d1712cab956..d030d1e0fe111 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -79,8 +79,11 @@ void handleLegacyDnsResolverData(
 Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
     const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) {
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
-  return Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(
-      typed_dns_resolver_config);
+  auto& factory =
+      Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
+  // Perform factory initialization.
+  factory.init();
+  return factory;
 }
 
 // Create the default DNS resolver factory. apple for MacOS or c-ares for all others.
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index 5289ad08c9c16..7bb820fde8305 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -508,11 +508,6 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
                                              typed_dns_resolver_config) const override {
     envoy::extensions::network::dns_resolver::cares::v3::CaresDnsResolverConfig cares;
     std::vector<Network::Address::InstanceConstSharedPtr> resolvers;
-    // Initialize c-ares library in case first time.
-    if (!ares_library_initialized_) {
-      ares_library_init(ARES_LIB_INIT_ALL);
-      ares_library_initialized_ = true;
-    }
 
     ASSERT(dispatcher.isThreadSafe());
     // Only c-ares DNS factory will call into this function.
@@ -528,6 +523,13 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     return std::make_shared<Network::DnsResolverImpl>(cares, dispatcher, resolvers);
   }
 
+  void init() override {
+    // Initialize c-ares library in case first time.
+    if (!ares_library_initialized_) {
+      ares_library_initialized_ = true;
+      ares_library_init(ARES_LIB_INIT_ALL);
+    }
+  }
   void cleanup() override {
     // Cleanup c-ares library if initialized.
     if (ares_library_initialized_) {

From d22cb618ea8e5acb70e0ee8ae4f40282bf359e7e Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Mon, 27 Jun 2022 13:27:18 +0000
Subject: [PATCH 06/17]  fixing CI error

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/extensions/network/dns_resolver/cares/dns_impl.cc | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index 7bb820fde8305..ad9c7ba22f318 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -495,7 +495,6 @@ DnsResolverImpl::AddrInfoPendingResolution::availableInterfaces() {
 // c-ares DNS resolver factory
 class CaresDnsResolverFactory : public DnsResolverFactory {
 public:
-  CaresDnsResolverFactory() : ares_library_initialized_(false) {}
   std::string name() const override { return std::string(CaresDnsResolver); }
 
   ProtobufTypes::MessagePtr createEmptyConfigProto() override {
@@ -538,7 +537,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
   }
 
 private:
-  mutable bool ares_library_initialized_;
+  mutable bool ares_library_initialized_{false};
 };
 
 // Register the CaresDnsResolverFactory

From f37c515b1c334005fa89f1ad73b76d432a3617f9 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Mon, 27 Jun 2022 23:45:45 +0000
Subject: [PATCH 07/17]  adding mutex to protect ares_library_init() operation
 race

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/extensions/network/dns_resolver/cares/dns_impl.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index ad9c7ba22f318..dca6c3fbff86c 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -524,6 +524,8 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
 
   void init() override {
     // Initialize c-ares library in case first time.
+    absl::Mutex mutex;
+    absl::MutexLock lock(&mutex);
     if (!ares_library_initialized_) {
       ares_library_initialized_ = true;
       ares_library_init(ARES_LIB_INIT_ALL);

From 838aa9cae0e997ef20f6d5ce0d526829d9d2e799 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Tue, 28 Jun 2022 20:05:51 +0000
Subject: [PATCH 08/17] addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                         | 12 ++++++++++++
 source/exe/process_wide.cc                           |  3 ++-
 .../network/dns_resolver/cares/dns_impl.cc           |  8 +++++---
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index e498614c3f8ec..96c5b7975948f 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -26,7 +26,19 @@ class DnsResolverFactory : public Config::TypedFactory {
       const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) const PURE;
 
   std::string category() const override { return std::string(DnsResolverCategory); }
+
+  /*
+   * Initialize the related data for this type of DNS resolver.
+   * For some DNS resolvers, like c-ares, there are some specific data structure
+   * needs to be initialized before using it to resolve target.
+   */
   virtual void init() {}
+
+  /*
+   * Cleanup the related data for this type of DNS resolver.
+   * For some DNS resolvers, like c-ares, there are some specific data structure
+   * needs to be cleaned up before terminates Envoy.
+   */
   virtual void cleanup() {}
 };
 
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index 082e30f9b9802..bb5a8f451cc2a 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,7 +57,8 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    // Cleanup c-ares library if it is linked in.
+    // The c-ares library init is done in a thread-safe way when it is actually used for resolving.
+    // Clean it up here in case it is ever used.
     if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
             std::string(Network::CaresDnsResolver), true)) {
       dns_factory->cleanup();
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index dca6c3fbff86c..0ccd114b090db 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -524,8 +524,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
 
   void init() override {
     // Initialize c-ares library in case first time.
-    absl::Mutex mutex;
-    absl::MutexLock lock(&mutex);
+    absl::MutexLock lock(&mutex_);
     if (!ares_library_initialized_) {
       ares_library_initialized_ = true;
       ares_library_init(ARES_LIB_INIT_ALL);
@@ -533,13 +532,16 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
   }
   void cleanup() override {
     // Cleanup c-ares library if initialized.
+    absl::MutexLock lock(&mutex_);
     if (ares_library_initialized_) {
+      ares_library_initialized_ = false;
       ares_library_cleanup();
     }
   }
 
 private:
-  mutable bool ares_library_initialized_{false};
+  bool ares_library_initialized_ ABSL_GUARDED_BY(mutex_){false};
+  absl::Mutex mutex_;
 };
 
 // Register the CaresDnsResolverFactory

From e4576ac96b7f56e1695ee4ae610f1d36a63fcd97 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Tue, 28 Jun 2022 23:06:43 +0000
Subject: [PATCH 09/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                           | 10 +++++-----
 source/common/network/dns_resolver/dns_factory_util.cc |  2 +-
 source/exe/process_wide.cc                             |  2 +-
 .../extensions/network/dns_resolver/cares/dns_impl.cc  |  4 ++--
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index 96c5b7975948f..b7ff32002c447 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -15,7 +15,7 @@ constexpr absl::string_view DnsResolverCategory = "envoy.network.dns_resolver";
 
 class DnsResolverFactory : public Config::TypedFactory {
 public:
-  /*
+  /**
    * @returns a DnsResolver object.
    * @param dispatcher: the local dispatcher thread
    * @param api: API interface to interact with system resources
@@ -27,19 +27,19 @@ class DnsResolverFactory : public Config::TypedFactory {
 
   std::string category() const override { return std::string(DnsResolverCategory); }
 
-  /*
+  /**
    * Initialize the related data for this type of DNS resolver.
    * For some DNS resolvers, like c-ares, there are some specific data structure
    * needs to be initialized before using it to resolve target.
    */
-  virtual void init() {}
+  virtual void initialize() {}
 
-  /*
+  /**
    * Cleanup the related data for this type of DNS resolver.
    * For some DNS resolvers, like c-ares, there are some specific data structure
    * needs to be cleaned up before terminates Envoy.
    */
-  virtual void cleanup() {}
+  virtual void terminate() {}
 };
 
 } // namespace Network
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index d030d1e0fe111..a88f163ab1170 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -82,7 +82,7 @@ Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
   auto& factory =
       Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
   // Perform factory initialization.
-  factory.init();
+  factory.initialize();
   return factory;
 }
 
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index bb5a8f451cc2a..6100396ad83bd 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -61,7 +61,7 @@ ProcessWide::~ProcessWide() {
     // Clean it up here in case it is ever used.
     if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
             std::string(Network::CaresDnsResolver), true)) {
-      dns_factory->cleanup();
+      dns_factory->terminate();
     }
   }
 }
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index 0ccd114b090db..cd739286ce7ca 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -522,7 +522,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     return std::make_shared<Network::DnsResolverImpl>(cares, dispatcher, resolvers);
   }
 
-  void init() override {
+  void initialize() override {
     // Initialize c-ares library in case first time.
     absl::MutexLock lock(&mutex_);
     if (!ares_library_initialized_) {
@@ -530,7 +530,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
       ares_library_init(ARES_LIB_INIT_ALL);
     }
   }
-  void cleanup() override {
+  void terminate() override {
     // Cleanup c-ares library if initialized.
     absl::MutexLock lock(&mutex_);
     if (ares_library_initialized_) {

From 8a3d24e8f143aceb7db15c8e4b2810fcfe9610c3 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Wed, 29 Jun 2022 01:40:07 +0000
Subject: [PATCH 10/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/common/network/dns_resolver/dns_factory_util.cc | 1 -
 1 file changed, 1 deletion(-)

diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index a88f163ab1170..462d23467dd75 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -81,7 +81,6 @@ Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
   auto& factory =
       Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
-  // Perform factory initialization.
   factory.initialize();
   return factory;
 }

From ca388d03a84cc34338f5e3d2dd52d66479ccbcd1 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Thu, 30 Jun 2022 03:10:38 +0000
Subject: [PATCH 11/17]  perform factory init for c-ares only

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/common/network/dns_resolver/dns_factory_util.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index 462d23467dd75..50ad5bb745ae5 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -81,7 +81,9 @@ Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
   auto& factory =
       Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
-  factory.initialize();
+  if (factory.name() == std::string(CaresDnsResolver)) {
+    factory.initialize();
+  }
   return factory;
 }
 

From 09f15d793bb51551ee2320e8e69504f86bb72680 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Thu, 30 Jun 2022 22:01:16 +0000
Subject: [PATCH 12/17]  make the factory init/terminate generic

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 source/common/config/utility.h                        | 11 +++++++++++
 .../common/network/dns_resolver/dns_factory_util.cc   |  4 +---
 source/exe/process_wide.cc                            |  8 +++-----
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/source/common/config/utility.h b/source/common/config/utility.h
index 311a4b75d7dca..2c3d729e78d8e 100644
--- a/source/common/config/utility.h
+++ b/source/common/config/utility.h
@@ -241,6 +241,17 @@ class Utility {
                                    POOL_HISTOGRAM(scope))};
   }
 
+
+
+  /**
+   * Get the hash map for this factory.
+   */
+  template <class Factory>
+  static absl::flat_hash_map<std::string, Factory*>&  getFactoryMap() {
+    return Registry::FactoryRegistry<Factory>::factories();
+  }
+
+
   /**
    * Get a Factory from the registry with a particular name (and templated type) with error checking
    * to ensure the name and factory are valid.
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index 50ad5bb745ae5..462d23467dd75 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -81,9 +81,7 @@ Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
   auto& factory =
       Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
-  if (factory.name() == std::string(CaresDnsResolver)) {
-    factory.initialize();
-  }
+  factory.initialize();
   return factory;
 }
 
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index 6100396ad83bd..77d14b71d6b82 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,11 +57,9 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    // The c-ares library init is done in a thread-safe way when it is actually used for resolving.
-    // Clean it up here in case it is ever used.
-    if (auto* dns_factory = Config::Utility::getAndCheckFactoryByName<Network::DnsResolverFactory>(
-            std::string(Network::CaresDnsResolver), true)) {
-      dns_factory->terminate();
+    for (const auto& dns_factory :
+         Config::Utility::getFactoryMap<Network::DnsResolverFactory>()) {
+      dns_factory.second->terminate();
     }
   }
 }

From 6a26ee90d6705981f65681cea98083cfbf66c8c9 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 1 Jul 2022 13:47:49 +0000
Subject: [PATCH 13/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                          |  9 +++++++++
 source/common/config/utility.h                        | 11 -----------
 source/exe/process_wide.cc                            |  5 +----
 .../extensions/network/dns_resolver/cares/dns_impl.cc |  5 ++++-
 4 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index b7ff32002c447..b6a9d260a3453 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -42,5 +42,14 @@ class DnsResolverFactory : public Config::TypedFactory {
   virtual void terminate() {}
 };
 
+/**
+ * Terminate the DNS resolver factories.
+ */
+static inline void terminateDnsResolverFactories() {
+  auto& factories = Registry::FactoryRegistry<Network::DnsResolverFactory>::factories();
+  std::for_each(factories.begin(), factories.end(),
+                [](auto& factory_it) { factory_it.second->terminate(); });
+}
+
 } // namespace Network
 } // namespace Envoy
diff --git a/source/common/config/utility.h b/source/common/config/utility.h
index 2c3d729e78d8e..311a4b75d7dca 100644
--- a/source/common/config/utility.h
+++ b/source/common/config/utility.h
@@ -241,17 +241,6 @@ class Utility {
                                    POOL_HISTOGRAM(scope))};
   }
 
-
-
-  /**
-   * Get the hash map for this factory.
-   */
-  template <class Factory>
-  static absl::flat_hash_map<std::string, Factory*>&  getFactoryMap() {
-    return Registry::FactoryRegistry<Factory>::factories();
-  }
-
-
   /**
    * Get a Factory from the registry with a particular name (and templated type) with error checking
    * to ensure the name and factory are valid.
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index 77d14b71d6b82..74d6a944fb00e 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,10 +57,7 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    for (const auto& dns_factory :
-         Config::Utility::getFactoryMap<Network::DnsResolverFactory>()) {
-      dns_factory.second->terminate();
-    }
+    Network::terminateDnsResolverFactories();
   }
 }
 
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index cd739286ce7ca..e210153851b61 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -493,7 +493,8 @@ DnsResolverImpl::AddrInfoPendingResolution::availableInterfaces() {
 }
 
 // c-ares DNS resolver factory
-class CaresDnsResolverFactory : public DnsResolverFactory {
+class CaresDnsResolverFactory : public DnsResolverFactory,
+                                public Logger::Loggable<Logger::Id::dns>{
 public:
   std::string name() const override { return std::string(CaresDnsResolver); }
 
@@ -527,6 +528,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     absl::MutexLock lock(&mutex_);
     if (!ares_library_initialized_) {
       ares_library_initialized_ = true;
+      ENVOY_LOG(info, "c-ares library initialized.");
       ares_library_init(ARES_LIB_INIT_ALL);
     }
   }
@@ -535,6 +537,7 @@ class CaresDnsResolverFactory : public DnsResolverFactory {
     absl::MutexLock lock(&mutex_);
     if (ares_library_initialized_) {
       ares_library_initialized_ = false;
+      ENVOY_LOG(info, "c-ares library cleaned up.");
       ares_library_cleanup();
     }
   }

From 76faa30f27897155148fa8f341d6127dce755431 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 1 Jul 2022 15:16:47 +0000
Subject: [PATCH 14/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                  | 22 +++++++++++--------
 .../network/dns_resolver/dns_factory_util.cc  | 19 ++++++++++++----
 source/exe/process_wide.cc                    |  2 +-
 .../network/dns_resolver/cares/dns_impl.cc    |  2 +-
 4 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index b6a9d260a3453..65a62d84836c8 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -40,16 +40,20 @@ class DnsResolverFactory : public Config::TypedFactory {
    * needs to be cleaned up before terminates Envoy.
    */
   virtual void terminate() {}
-};
 
-/**
- * Terminate the DNS resolver factories.
- */
-static inline void terminateDnsResolverFactories() {
-  auto& factories = Registry::FactoryRegistry<Network::DnsResolverFactory>::factories();
-  std::for_each(factories.begin(), factories.end(),
-                [](auto& factory_it) { factory_it.second->terminate(); });
-}
+  /**
+   * Find the DNS resolver factory based on the typed config and initialize it.
+   * @returns the DNS Resolver factory.
+   * @param typed_dns_resolver_config: the typed DNS resolver config
+   */
+  static Network::DnsResolverFactory& initializeDnsResolverFactory(
+      const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config);
+
+  /**
+   * Terminate the DNS resolver factories.
+   */
+  static void terminateDnsResolverFactories();
+};
 
 } // namespace Network
 } // namespace Envoy
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index 462d23467dd75..51554ca2fd09e 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -79,10 +79,7 @@ void handleLegacyDnsResolverData(
 Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
     const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) {
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
-  auto& factory =
-      Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
-  factory.initialize();
-  return factory;
+  return DnsResolverFactory::initializeDnsResolverFactory(typed_dns_resolver_config);
 }
 
 // Create the default DNS resolver factory. apple for MacOS or c-ares for all others.
@@ -94,5 +91,19 @@ Network::DnsResolverFactory& createDefaultDnsResolverFactory(
   return createDnsResolverFactoryFromTypedConfig(typed_dns_resolver_config);
 }
 
+Network::DnsResolverFactory& DnsResolverFactory::initializeDnsResolverFactory(
+    const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) {
+  auto& factory =
+      Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
+  factory.initialize();
+  return factory;
+}
+
+void DnsResolverFactory::terminateDnsResolverFactories() {
+  auto& factories = Registry::FactoryRegistry<Network::DnsResolverFactory>::factories();
+  std::for_each(factories.begin(), factories.end(),
+                [](auto& factory_it) { factory_it.second->terminate(); });
+}
+
 } // namespace Network
 } // namespace Envoy
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index 74d6a944fb00e..e577d7f7724c2 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,7 +57,7 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    Network::terminateDnsResolverFactories();
+    Network::DnsResolverFactory::terminateDnsResolverFactories();
   }
 }
 
diff --git a/source/extensions/network/dns_resolver/cares/dns_impl.cc b/source/extensions/network/dns_resolver/cares/dns_impl.cc
index e210153851b61..6d14b89fbe48d 100644
--- a/source/extensions/network/dns_resolver/cares/dns_impl.cc
+++ b/source/extensions/network/dns_resolver/cares/dns_impl.cc
@@ -494,7 +494,7 @@ DnsResolverImpl::AddrInfoPendingResolution::availableInterfaces() {
 
 // c-ares DNS resolver factory
 class CaresDnsResolverFactory : public DnsResolverFactory,
-                                public Logger::Loggable<Logger::Id::dns>{
+                                public Logger::Loggable<Logger::Id::dns> {
 public:
   std::string name() const override { return std::string(CaresDnsResolver); }
 

From 8f2cb43c66193fe6871bf27dde2531c19b371bdf Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 1 Jul 2022 16:21:17 +0000
Subject: [PATCH 15/17]  addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                           | 8 ++++----
 source/common/network/dns_resolver/dns_factory_util.cc | 6 +++---
 source/exe/BUILD                                       | 2 +-
 source/exe/process_wide.cc                             | 2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index 65a62d84836c8..8cdfda1e64840 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -42,17 +42,17 @@ class DnsResolverFactory : public Config::TypedFactory {
   virtual void terminate() {}
 
   /**
-   * Find the DNS resolver factory based on the typed config and initialize it.
+   * Create the DNS resolver factory based on the typed config and initialize it.
    * @returns the DNS Resolver factory.
    * @param typed_dns_resolver_config: the typed DNS resolver config
    */
-  static Network::DnsResolverFactory& initializeDnsResolverFactory(
+  static Network::DnsResolverFactory& createFactory(
       const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config);
 
   /**
-   * Terminate the DNS resolver factories.
+   * Terminate the DNS resolver factory.
    */
-  static void terminateDnsResolverFactories();
+  static void terminateFactory();
 };
 
 } // namespace Network
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index 51554ca2fd09e..ce0e1ed708d74 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -79,7 +79,7 @@ void handleLegacyDnsResolverData(
 Network::DnsResolverFactory& createDnsResolverFactoryFromTypedConfig(
     const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) {
   ENVOY_LOG_MISC(debug, "create DNS resolver type: {}", typed_dns_resolver_config.name());
-  return DnsResolverFactory::initializeDnsResolverFactory(typed_dns_resolver_config);
+  return DnsResolverFactory::createFactory(typed_dns_resolver_config);
 }
 
 // Create the default DNS resolver factory. apple for MacOS or c-ares for all others.
@@ -91,7 +91,7 @@ Network::DnsResolverFactory& createDefaultDnsResolverFactory(
   return createDnsResolverFactoryFromTypedConfig(typed_dns_resolver_config);
 }
 
-Network::DnsResolverFactory& DnsResolverFactory::initializeDnsResolverFactory(
+Network::DnsResolverFactory& DnsResolverFactory::createFactory(
     const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config) {
   auto& factory =
       Config::Utility::getAndCheckFactory<Network::DnsResolverFactory>(typed_dns_resolver_config);
@@ -99,7 +99,7 @@ Network::DnsResolverFactory& DnsResolverFactory::initializeDnsResolverFactory(
   return factory;
 }
 
-void DnsResolverFactory::terminateDnsResolverFactories() {
+void DnsResolverFactory::terminateFactory() {
   auto& factories = Registry::FactoryRegistry<Network::DnsResolverFactory>::factories();
   std::for_each(factories.begin(), factories.end(),
                 [](auto& factory_it) { factory_it.second->terminate(); });
diff --git a/source/exe/BUILD b/source/exe/BUILD
index 7059a446017ff..cc0796ed99007 100644
--- a/source/exe/BUILD
+++ b/source/exe/BUILD
@@ -142,10 +142,10 @@ envoy_cc_library(
     srcs = ["process_wide.cc"],
     hdrs = ["process_wide.h"],
     deps = [
-        "//envoy/network:dns_resolver_interface",
         "//source/common/common:assert_lib",
         "//source/common/event:libevent_lib",
         "//source/common/http/http2:nghttp2_lib",
+        "//source/common/network/dns_resolver:dns_factory_util_lib",
         "//source/server:proto_descriptors_lib",
     ],
 )
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index e577d7f7724c2..c588a84181c57 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,7 +57,7 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    Network::DnsResolverFactory::terminateDnsResolverFactories();
+    Network::DnsResolverFactory::terminateFactory();
   }
 }
 

From 10a71edacbfa3efadbdb2c25434799c967b39489 Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 1 Jul 2022 16:43:21 +0000
Subject: [PATCH 16/17]  fixing CI format error

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index 8cdfda1e64840..e62d4dcf628cc 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -46,8 +46,8 @@ class DnsResolverFactory : public Config::TypedFactory {
    * @returns the DNS Resolver factory.
    * @param typed_dns_resolver_config: the typed DNS resolver config
    */
-  static Network::DnsResolverFactory& createFactory(
-      const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config);
+  static Network::DnsResolverFactory&
+  createFactory(const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config);
 
   /**
    * Terminate the DNS resolver factory.

From 629e580a8ae19dab92eb7c3a5eeae8707c298d0f Mon Sep 17 00:00:00 2001
From: Yanjun Xiang <yanjunxiang@google.com>
Date: Fri, 1 Jul 2022 17:38:54 +0000
Subject: [PATCH 17/17] addressing comments

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>
---
 envoy/network/dns_resolver.h                           | 4 ++--
 source/common/network/dns_resolver/dns_factory_util.cc | 2 +-
 source/exe/process_wide.cc                             | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/envoy/network/dns_resolver.h b/envoy/network/dns_resolver.h
index e62d4dcf628cc..3562f8756e94f 100644
--- a/envoy/network/dns_resolver.h
+++ b/envoy/network/dns_resolver.h
@@ -50,9 +50,9 @@ class DnsResolverFactory : public Config::TypedFactory {
   createFactory(const envoy::config::core::v3::TypedExtensionConfig& typed_dns_resolver_config);
 
   /**
-   * Terminate the DNS resolver factory.
+   * Call the terminate method on all the registered DNS resolver factories.
    */
-  static void terminateFactory();
+  static void terminateFactories();
 };
 
 } // namespace Network
diff --git a/source/common/network/dns_resolver/dns_factory_util.cc b/source/common/network/dns_resolver/dns_factory_util.cc
index ce0e1ed708d74..d06f1186fb561 100644
--- a/source/common/network/dns_resolver/dns_factory_util.cc
+++ b/source/common/network/dns_resolver/dns_factory_util.cc
@@ -99,7 +99,7 @@ Network::DnsResolverFactory& DnsResolverFactory::createFactory(
   return factory;
 }
 
-void DnsResolverFactory::terminateFactory() {
+void DnsResolverFactory::terminateFactories() {
   auto& factories = Registry::FactoryRegistry<Network::DnsResolverFactory>::factories();
   std::for_each(factories.begin(), factories.end(),
                 [](auto& factory_it) { factory_it.second->terminate(); });
diff --git a/source/exe/process_wide.cc b/source/exe/process_wide.cc
index c588a84181c57..9e93e9c48f4b4 100644
--- a/source/exe/process_wide.cc
+++ b/source/exe/process_wide.cc
@@ -57,7 +57,7 @@ ProcessWide::~ProcessWide() {
 
   ASSERT(init_data.count_ > 0);
   if (--init_data.count_ == 0) {
-    Network::DnsResolverFactory::terminateFactory();
+    Network::DnsResolverFactory::terminateFactories();
   }
 }