Windows平台RTMP推送|轻量级RTSP服务录像模块如何支持中文路径？

技术背景

我们在做Windows平台RTMP推送、轻量级RTSP服务录像模块的时候，部分开发者抱怨路径无法设置中文，只能设置为英文。

以C#的接口为例，早期的设计如下：

   /** 设置本地录像目录, 必须是英文目录，否则会失败*/[DllImport(@"SmartPublisherSDK.dll")]public static extern UInt32 NT_PB_SetRecorderDirectory(IntPtr handle, [MarshalAs(UnmanagedType.LPStr)] String dir, IntPtr pReserve);

考虑到一些场景的特殊性，可能需要中文路径，我们设计的接口如下：

        /** 设置本地录像目录, 支持中文目录, 需要设置宽字符，比如L"D:\\xxx\\gg"*/[DllImport(@"SmartPublisherSDK.dll")]public static extern UInt32 NT_PB_SetRecorderDirectoryW(IntPtr handle, [MarshalAs(UnmanagedType.LPWStr)]String dir, IntPtr pReserve);

调用如下，以调用开始录像、暂停录像、停止录像为例，调用逻辑如下，可以看到除了中文路径诉求，录像模块还可以添加前缀、添加文字、水印：

       public bool StartRecorder(){if (is_empty_handle() || is_recording())return false;//string edit_rec_dir = "D:\\dntest";string edit_rec_dir = "D:\\推送端录像";if (String.IsNullOrEmpty(edit_rec_dir)){Console.WriteLine("请设置录像目录");return false;}uint ret = NTSmartPublisherSDK.NT_PB_SetRecorderDirectoryW(handle_, edit_rec_dir, IntPtr.Zero);if (NTBaseCodeDefine.NT_ERC_OK != ret){try_close_handle();return false;}uint rec_max_file_size = 512 * 1024;NTSmartPublisherSDK.NT_PB_SetRecorderFileMaxSize(handle_, rec_max_file_size);NT_PB_RecorderFileNameRuler rec_name_ruler = new NT_PB_RecorderFileNameRuler();String rec_file_name_prefix_ = "transcode-rec";rec_name_ruler.file_name_prefix_ = rec_file_name_prefix_.ToString();rec_name_ruler.append_date_ = 1;rec_name_ruler.append_time_ = 1;NTSmartPublisherSDK.NT_PB_SetRecorderFileNameRuler(handle_, ref rec_name_ruler);if (NTBaseCodeDefine.NT_ERC_OK != NTSmartPublisherSDK.NT_PB_StartRecorder(handle_, IntPtr.Zero)){try_close_handle();return false;}shared_lock_.EnterWriteLock();try{handle_reference_count_++;is_recording_ = true;}finally{shared_lock_.ExitWriteLock();}return true;}public UInt32 PauseRecorder(bool is_pause){if (is_empty_handle() || !is_recording())return NTBaseCodeDefine.NT_ERC_FAILED;UInt32 ret = NTBaseCodeDefine.NT_ERC_OK;if (is_pause){ret = NTSmartPublisherSDK.NT_PB_PauseRecorder(handle_, 1);if ((UInt32)NT.NTSmartPublisherDefine.NT_PB_E_ERROR_CODE.NT_ERC_PB_NEED_RETRY == ret){Console.WriteLine("暂停录像失败, 请重新尝试!");return ret;}else if (NTBaseCodeDefine.NT_ERC_OK == ret){//btn_pause_rec.Text = "恢复录像";}}else{ret = NTSmartPublisherSDK.NT_PB_PauseRecorder(handle_, 0);if ((UInt32)NT.NTSmartPublisherDefine.NT_PB_E_ERROR_CODE.NT_ERC_PB_NEED_RETRY == ret){Console.WriteLine("恢复录像失败, 请重新尝试!");return ret;}else if (NTBaseCodeDefine.NT_ERC_OK == ret){//btn_pause_rec.Text = "暂停录像";}}return ret;}public void StopRecorder(){if (is_empty_handle() || !is_recording())return;shared_lock_.EnterWriteLock();try{is_recording_ = false;handle_reference_count_--;}finally{shared_lock_.ExitWriteLock();}NTSmartPublisherSDK.NT_PB_StopRecorder(handle_);try_close_handle();}

开始录像和录像完成后，提示如下：

        private void PbEventCallBack(UInt32 event_id,Int64 param1,Int64 param2,UInt64 param3,UInt64 param4,[MarshalAs(UnmanagedType.LPStr)] String param5,[MarshalAs(UnmanagedType.LPStr)] String param6,IntPtr param7){String event_log = "";switch (event_id){......case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_RECORDER_START_NEW_FILE:event_log = " start new recorder file";byte[] utf8_bytes = Encoding.Default.GetBytes(param5);byte[] default_bytes = Encoding.Convert(Encoding.UTF8, Encoding.Default, utf8_bytes);String file_name = Encoding.Default.GetString(default_bytes);if (!String.IsNullOrEmpty(file_name)){event_log = event_log + " file name:" + file_name;}break;case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_ONE_RECORDER_FILE_FINISHED:event_log = " finish recorder file";byte[] finished_utf8_bytes = Encoding.Default.GetBytes(param5);byte[] finished_default_bytes = Encoding.Convert(Encoding.UTF8, Encoding.Default, finished_utf8_bytes);String finished_file_name = Encoding.Default.GetString(finished_default_bytes);if (!String.IsNullOrEmpty(finished_file_name)){event_log = event_log + " file name:" + finished_file_name;}break;.......default:break;}EventGetPublisherEventMsg(event_log);}