diff --git a/src/main.cpp b/src/main.cpp
index 02ba502..401e0ec 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -6,43 +6,29 @@
 #include <thread>
 #include <atomic>
 #include <csignal>
+#include <unistd.h> // write, STDOUT_FILENO
+#include <chrono>
 
 std::atomic<bool> g_running(true);
 
-// main.cpp - 修改signalHandler
-void signalHandler(int signum)
+static void minimal_signal_handler(int signum)
 {
-    static bool already_called = false;
-    if (already_called)
-        return;
-    already_called = true;
-
-    LOG_INFO("[MAIN] Received signal " + std::to_string(signum) + ", shutting down...");
-    g_running = false;
-
-    // 停止RTSP循环
-    RTSPManager::stop();
-
-    // 记录停止时间
-    auto start_time = std::chrono::steady_clock::now();
-
-    // 等待一段时间让线程退出
-    while (std::chrono::steady_clock::now() - start_time < std::chrono::seconds(3))
-    {
-        std::this_thread::sleep_for(std::chrono::milliseconds(100));
-    }
-
-    LOG_INFO("[MAIN] Force exiting after waiting for threads");
-    exit(1);
+    // 只做非常有限且 async-signal-safe 的操作
+    g_running.store(false, std::memory_order_relaxed);
+    const char msg[] = "[MAIN] Signal received, initiating shutdown...\n";
+    write(STDERR_FILENO, msg, sizeof(msg) - 1);
+    // 不要调用 LOG_*、malloc、std::string、mutex、exit 等
 }
 
 int main()
 {
-    struct sigaction sigIntHandler;
-    sigIntHandler.sa_handler = signalHandler;
-    sigemptyset(&sigIntHandler.sa_mask);
-    sigIntHandler.sa_flags = 0;
-    sigaction(SIGINT, &sigIntHandler, NULL);
+    // 安装信号处理（SIGINT 和 SIGTERM）
+    struct sigaction sigAct{};
+    sigAct.sa_handler = minimal_signal_handler;
+    sigemptyset(&sigAct.sa_mask);
+    sigAct.sa_flags = 0;
+    sigaction(SIGINT, &sigAct, nullptr);
+    sigaction(SIGTERM, &sigAct, nullptr);
     signal(SIGPIPE, SIG_IGN);
 
     // 初始化日志文件
@@ -59,31 +45,82 @@ int main()
         return -1;
     }
 
+    // 线程退出标志，用于超时等待
+    std::atomic<bool> rtsp_thread_exited(false);
+    std::atomic<bool> mqtt_thread_exited(false);
+
     // 先在主线程初始化 GStreamer
     RTSPManager::init();
 
     std::thread rtsp_thread([&]()
-                            { RTSPManager::start(g_app_config.cameras); });
-    std::thread mqtt_thread(mqtt_client_thread_func);
+                            {
+        RTSPManager::start(g_app_config.cameras);
+        rtsp_thread_exited.store(true, std::memory_order_relaxed); });
+
+    std::thread mqtt_thread([&]()
+                            {
+        mqtt_client_thread_func();
+        mqtt_thread_exited.store(true, std::memory_order_relaxed); });
 
     // 等待退出信号
-    while (g_running)
+    while (g_running.load(std::memory_order_relaxed))
         std::this_thread::sleep_for(std::chrono::milliseconds(200));
 
-    // 在main函数等待线程结束处添加日志
+    LOG_INFO("[MAIN] Shutdown requested, stopping services...");
+
+    // 等线程优雅退出：总等待时间 (可调整)
+    const auto max_wait = std::chrono::seconds(5);
+    const auto poll_interval = std::chrono::milliseconds(100);
+    auto deadline = std::chrono::steady_clock::now() + max_wait;
+
+    // 等 RTSP 线程退出
+    while (!rtsp_thread_exited.load(std::memory_order_relaxed) &&
+           std::chrono::steady_clock::now() < deadline)
+    {
+        std::this_thread::sleep_for(poll_interval);
+    }
     if (rtsp_thread.joinable())
     {
-        LOG_INFO("[MAIN] Waiting for RTSP thread to finish...");
-        rtsp_thread.join();
-        LOG_INFO("[MAIN] RTSP thread finished");
+        if (rtsp_thread_exited.load(std::memory_order_relaxed))
+        {
+            rtsp_thread.join();
+            LOG_INFO("[MAIN] RTSP thread finished and joined.");
+        }
+        else
+        {
+            LOG_WARN("[MAIN] RTSP thread did not exit within timeout.");
+        }
+    }
+
+    // 等 MQTT 线程退出
+    deadline = std::chrono::steady_clock::now() + max_wait;
+    while (!mqtt_thread_exited.load(std::memory_order_relaxed) &&
+           std::chrono::steady_clock::now() < deadline)
+    {
+        std::this_thread::sleep_for(poll_interval);
     }
     if (mqtt_thread.joinable())
     {
-        LOG_INFO("[MAIN] Waiting for MQTT thread to finish...");
-        mqtt_thread.join();
-        LOG_INFO("[MAIN] MQTT thread finished");
+        if (mqtt_thread_exited.load(std::memory_order_relaxed))
+        {
+            mqtt_thread.join();
+            LOG_INFO("[MAIN] MQTT thread finished and joined.");
+        }
+        else
+        {
+            LOG_WARN("[MAIN] MQTT thread did not exit within timeout.");
+        }
+    }
+
+    // 如果某些线程仍未退出，强制结束进程（不会跑全局析构）
+    if ((rtsp_thread.joinable() && !rtsp_thread_exited.load(std::memory_order_relaxed)) ||
+        (mqtt_thread.joinable() && !mqtt_thread_exited.load(std::memory_order_relaxed)))
+    {
+        LOG_ERROR("[MAIN] Threads did not exit in time. Forcing immediate termination.");
+        _exit(1); // 强制退出（不会调用 atexit handlers）
     }
 
     LOG_INFO("[MAIN] Program exited cleanly.");
+
     return 0;
 }
\ No newline at end of file