fix exit bug (#57)

修复进程退出时，libevent 无法正常结束循环的BUG

1.patch

+diff --git a/src/observer/CMakeLists.txt b/src/observer/CMakeLists.txt
+index 1e156f2..37f5f86 100644
+--- a/src/observer/CMakeLists.txt
++++ b/src/observer/CMakeLists.txt
+@@ -24,7 +24,7 @@ FOREACH (F ${ALL_SRC})
+ 
+ ENDFOREACH (F)
+ 
+-SET(LIBRARIES common pthread dl event jsoncpp)
++SET(LIBRARIES common pthread dl event_pthreads event jsoncpp)
+ 
+ # 指定目标文件位置
+ SET(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/../../bin)
+diff --git a/src/observer/main.cpp b/src/observer/main.cpp
+index 4fff6da..112255e 100644
+--- a/src/observer/main.cpp
++++ b/src/observer/main.cpp
+@@ -137,8 +137,6 @@ void *quit_thread_func(void *_signum)
+   LOG_INFO("Receive signal: %ld", signum);
+   if (g_server) {
+     g_server->shutdown();
+-    delete g_server;
+-    g_server = nullptr;
+   }
+   return nullptr;
+ }
+@@ -169,4 +167,6 @@ int main(int argc, char **argv)
+   LOG_INFO("Server stopped");
+ 
+   cleanup();
++
++  delete g_server;
+ }
+diff --git a/src/observer/net/server.cpp b/src/observer/net/server.cpp
+index e87ad0d..2c6cef6 100644
+--- a/src/observer/net/server.cpp
++++ b/src/observer/net/server.cpp
+@@ -26,6 +26,7 @@ See the Mulan PSL v2 for more details. */
+ #include <sys/types.h>
+ #include <sys/un.h>
+ #include <unistd.h>
++#include <event2/thread.h>
+ 
+ #include "common/lang/mutex.h"
+ #include "common/log/log.h"
+@@ -411,6 +412,7 @@ int Server::start_unix_socket_server()
+ 
+ int Server::serve()
+ {
++  evthread_use_pthreads();
+   event_base_ = event_base_new();
+   if (event_base_ == nullptr) {
+     LOG_ERROR("Failed to create event base, %s.", strerror(errno));
+@@ -425,19 +427,6 @@ int Server::serve()
+ 
+   event_base_dispatch(event_base_);
+ 
+-  return 0;
+-}
+-
+-void Server::shutdown()
+-{
+-  LOG_INFO("Server shutting down");
+-
+-  // cleanup
+-  struct timeval exit_time;
+-  gettimeofday(&exit_time, nullptr);
+-  exit_time.tv_sec += 10;
+-  event_base_loopexit(event_base_, &exit_time);
+-
+   if (listen_ev_ != nullptr) {
+     event_del(listen_ev_);
+     event_free(listen_ev_);
+@@ -451,4 +440,16 @@ void Server::shutdown()
+ 
+   started_ = false;
+   LOG_INFO("Server quit");
++  return 0;
++}
++
++void Server::shutdown()
++{
++  LOG_INFO("Server shutting down");
++
++  // cleanup
++  if (event_base_ != nullptr && started_) {
++    started_ = false;
++    event_base_loopexit(event_base_, nullptr);
++  }
+ }
+

src/observer/CMakeLists.txt

@@ -24,7 +24,7 @@ FOREACH (F ${ALL_SRC})
 
 ENDFOREACH (F)
 
-SET(LIBRARIES common pthread dl event jsoncpp)
+SET(LIBRARIES common pthread dl event_pthreads event jsoncpp)
 
 # 指定目标文件位置
 SET(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/../../bin)

src/observer/main.cpp

@@ -137,8 +137,6 @@ void *quit_thread_func(void *_signum)
   LOG_INFO("Receive signal: %ld", signum);
   if (g_server) {
     g_server->shutdown();
-    delete g_server;
-    g_server = nullptr;
   }
   return nullptr;
 }
@@ -169,4 +167,6 @@ int main(int argc, char **argv)
   LOG_INFO("Server stopped");
 
   cleanup();
+
+  delete g_server;
 }

src/observer/net/server.cpp

@@ -26,6 +26,7 @@ See the Mulan PSL v2 for more details. */
 #include <sys/types.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <event2/thread.h>
 
 #include "common/lang/mutex.h"
 #include "common/log/log.h"
@@ -411,6 +412,7 @@ int Server::start_unix_socket_server()
 
 int Server::serve()
 {
+  evthread_use_pthreads();
   event_base_ = event_base_new();
   if (event_base_ == nullptr) {
     LOG_ERROR("Failed to create event base, %s.", strerror(errno));
@@ -425,19 +427,6 @@ int Server::serve()
 
   event_base_dispatch(event_base_);
 
-  return 0;
-}
-
-void Server::shutdown()
-{
-  LOG_INFO("Server shutting down");
-
-  // cleanup
-  struct timeval exit_time;
-  gettimeofday(&exit_time, nullptr);
-  exit_time.tv_sec += 10;
-  event_base_loopexit(event_base_, &exit_time);
-
   if (listen_ev_ != nullptr) {
     event_del(listen_ev_);
     event_free(listen_ev_);
@@ -451,4 +440,16 @@ void Server::shutdown()
 
   started_ = false;
   LOG_INFO("Server quit");
+  return 0;
+}
+
+void Server::shutdown()
+{
+  LOG_INFO("Server shutting down");
+
+  // cleanup
+  if (event_base_ != nullptr && started_) {
+    started_ = false;
+    event_base_loopexit(event_base_, nullptr);
+  }
 }