[shell] Correct order of atexit and shutdown handling.

examples/platform/efr32/matter_shell.cpp

@@ -71,7 +71,7 @@ void WaitForShellActivity()
 
 void startShellTask()
 {
-    int status = chip::Shell::streamer_init(chip::Shell::streamer_get());
+    int status = chip::Shell::Engine::Root().Init();
     assert(status == 0);
 
     // For now also register commands from shell_common (shell app).

examples/shell/esp32/main/main.cpp

@@ -36,6 +36,10 @@ extern "C" void app_main(void)
     chip::Platform::MemoryInit();
     chip::DeviceLayer::PlatformMgr().InitChipStack();
     chip::DeviceLayer::PlatformMgr().StartEventLoopTask();
+
+    int ret = Engine::Root().Init();
+    assert(ret == 0);
+
     cmd_ping_init();
     xTaskCreate(&chip_shell_task, "chip_shell", 2048, NULL, 5, NULL);
 }

examples/shell/mbed/main/main.cpp

@@ -84,7 +84,7 @@ int main()
     }
 
     // Initialize the default streamer that was linked.
-    ret = streamer_init(streamer_get());
+    ret = Engine::Root().Init();
     if (ret)
     {
         ChipLogError(Shell, "Streamer initialization failed [%d]", ret);

examples/shell/standalone/main.cpp

@@ -38,8 +38,8 @@ int main()
 #if CHIP_DEVICE_CONFIG_ENABLE_WPA
     chip::DeviceLayer::ConnectivityManagerImpl().StartWiFiManagement();
 #endif
-    // Initialize the default streamer that was linked.
-    const int rc = streamer_init(streamer_get());
+
+    const int rc = Engine::Root().Init();
 
     if (rc != 0)
     {

src/lib/shell/Engine.cpp

@@ -44,6 +44,16 @@ namespace Shell {
 
 Engine Engine::theEngineRoot;
 
+int Engine::Init()
+{
+    // Initialize the default streamer that was linked.
+    int error = streamer_init(streamer_get());
+
+    Engine::Root().RegisterDefaultCommands();
+
+    return error;
+}
+
 void Engine::ForEachCommand(shell_command_iterator_t * on_command, void * arg)
 {
     for (unsigned i = 0; i < _commandSetCount; i++)

src/lib/shell/Engine.h

@@ -152,6 +152,15 @@ class Engine
      */
     void RunMainLoop();
 
+    /**
+     * Initialize the Shell::Engine.
+     *
+     * Activates the linked streamer, registers default commands, and sets up exit handlers.
+     *
+     * @return 0 for success, otherwise failed.
+     */
+    int Init();
+
 private:
     static void ProcessShellLineTask(intptr_t context);
 };

src/lib/shell/MainLoopDefault.cpp

@@ -181,7 +181,6 @@ namespace Shell {
 
 void Engine::RunMainLoop()
 {
-    Engine::Root().RegisterDefaultCommands();
     streamer_printf(streamer_get(), CHIP_SHELL_PROMPT);
 
     while (true)

src/lib/shell/MainLoopEFR32.cpp

@@ -185,7 +185,6 @@ namespace Shell {
 
 void Engine::RunMainLoop()
 {
-    Engine::Root().RegisterDefaultCommands();
     streamer_printf(streamer_get(), kShellPrompt);
 
     while (true)

src/lib/shell/MainLoopESP32.cpp

@@ -70,10 +70,6 @@ namespace Shell {
 
 void Engine::RunMainLoop()
 {
-    int ret = chip::Shell::streamer_init(chip::Shell::streamer_get());
-    assert(ret == 0);
-
-    Engine::Root().RegisterDefaultCommands();
     while (true)
     {
         const char * prompt = LOG_COLOR_I "> " LOG_RESET_COLOR;

src/lib/shell/commands/Meta.cpp

@@ -40,11 +40,15 @@ namespace Shell {
 static CHIP_ERROR ExitHandler(int argc, char ** argv)
 {
     streamer_printf(streamer_get(), "Goodbye\r\n");
-    chip::DeviceLayer::PlatformMgr().Shutdown();
     exit(0);
     return CHIP_NO_ERROR;
 }
 
+static void AtExitShell()
+{
+    chip::DeviceLayer::PlatformMgr().Shutdown();
+}
+
 static CHIP_ERROR HelpHandler(int argc, char ** argv)
 {
     Engine::Root().ForEachCommand(PrintCommandHelp, nullptr);
@@ -65,6 +69,8 @@ void RegisterMetaCommands()
         { &VersionHandler, "version", "Output the software version" },
     };
 
+    std::atexit(AtExitShell);
+
     Engine::Root().RegisterCommands(sCmds, ArraySize(sCmds));
 }