[zephyr] Run shell commands in Matter thread

src/lib/shell/MainLoopZephyr.cpp

@@ -14,37 +14,100 @@
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */
-#include <zephyr/init.h>
-#include <zephyr/shell/shell.h>
-
 #include <lib/core/CHIPError.h>
 #include <lib/shell/Engine.h>
+#include <lib/shell/streamer.h>
 #include <lib/shell/streamer_zephyr.h>
+#include <platform/CHIPDeviceLayer.h>
+
+#include <zephyr/init.h>
+#include <zephyr/kernel.h>
+#include <zephyr/shell/shell.h>
+
+using namespace chip;
+using namespace chip::DeviceLayer;
+
+namespace {
+
+K_MUTEX_DEFINE(sShellMutex);
+K_CONDVAR_DEFINE(sCommandResultCondVar);
+CHIP_ERROR sCommandResult;
+
+// RAII helper for synchronizing access to resources shared between the Zephyr's shell thread,
+// which reads and parses the user input, and the the Matter thread, which executes a Matter
+// shell command and reports the result back to the shell thread.
+class ShellGuard
+{
+public:
+    ShellGuard() { k_mutex_lock(&sShellMutex, K_FOREVER); }
+    ~ShellGuard() { k_mutex_unlock(&sShellMutex); }
 
-using chip::Shell::Engine;
+    CHIP_ERROR WaitForCommandResult()
+    {
+        k_condvar_wait(&sCommandResultCondVar, &sShellMutex, K_FOREVER);
+        return sCommandResult;
+    }
 
-static int cmd_matter(const struct shell * shell, size_t argc, char ** argv)
+    void PutCommandResult(CHIP_ERROR error)
+    {
+        sCommandResult = error;
+        k_condvar_signal(&sCommandResultCondVar);
+    }
+};
+
+void ExecCommandInMatterThread(intptr_t argvAsInt)
 {
-    chip::Shell::streamer_set_shell(shell);
-    return (Engine::Root().ExecCommand(argc - 1, argv + 1) == CHIP_NO_ERROR) ? 0 : -ENOEXEC;
+    char ** argv = reinterpret_cast<char **>(argvAsInt);
+    int argc     = 0;
+
+    while (argv[argc] != nullptr)
+    {
+        argc++;
+    }
+
+    ShellGuard shellGuard;
+    shellGuard.PutCommandResult(Shell::Engine::Root().ExecCommand(argc, argv));
 }
 
-static int RegisterCommands()
+int ExecCommandInShellThread(const struct shell * shell, size_t argc, char ** argv)
 {
-    Engine::Root().RegisterDefaultCommands();
+    const CHIP_ERROR error = [shell, argv]() -> CHIP_ERROR {
+        ShellGuard shellGuard;
+        Shell::streamer_set_shell(shell);
+        ReturnErrorOnFailure(PlatformMgr().ScheduleWork(ExecCommandInMatterThread, reinterpret_cast<intptr_t>(argv + 1)));
+
+        return shellGuard.WaitForCommandResult();
+    }();
+
+    if (error != CHIP_NO_ERROR)
+    {
+        Shell::streamer_printf(Shell::streamer_get(), "Error: %" CHIP_ERROR_FORMAT "\r\n", error.Format());
+    }
+    else
+    {
+        Shell::streamer_printf(Shell::streamer_get(), "Done\r\n");
+    }
+
+    return error == CHIP_NO_ERROR ? 0 : -ENOEXEC;
+}
+
+int RegisterCommands()
+{
+    Shell::Engine::Root().RegisterDefaultCommands();
     return 0;
 }
 
-SYS_INIT(RegisterCommands, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
+} // namespace
 
-SHELL_CMD_ARG_REGISTER(matter, NULL, "Matter commands", cmd_matter, 1, 10);
+SYS_INIT(RegisterCommands, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
+SHELL_CMD_ARG_REGISTER(matter, NULL, "Matter commands", ExecCommandInShellThread, 1, CHIP_SHELL_MAX_TOKENS);
 
 namespace chip {
 namespace Shell {
 
 void Engine::RunMainLoop()
 {
-    // Intentionally empty as Zephyr has own thread handling shell
+    // Intentionally empty as Zephyr has its own thread handling shell.
 }
 
 } // namespace Shell