Multithreaded SDL_DestroyWindow blocking problem-CodePudding

using multi-threading implementation player, using ffmpeg decoding SDL, showing off the air in destruction form SDL_DestroyWindow and
The following is a part of the code:
//SDL thread 
Int sfp_refresh_thread (void * opaque) 
{
While (thread_exit==0) 
{
SDL_Event event; 
Event. The type=SFM_REFRESH_EVENT; 
SDL_PushEvent (& amp; The event); 
} 
//the Quit 
SDL_Event event; 
Event. The type=SFM_BREAK_EVENT; 
SDL_PushEvent (& amp; The event); 
return 0; 
} 

//video playback function 
Int simplest_ffmpeg_player (LPVOID lpParam) 
{
Int I, videoindex; 
AVCodecContext * pCodecCtx; 
AVCodec * pCodec; 
PFrame AVFrame * and * pFrameYUV; 
Uint8_t * out_buffer; 
AVPacket packet; 
Int ret, got_picture; 

//-- -- -- -- -- -- -- -- -- -- -- -- SDL -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
Int screen_w screen_h; 
SDL_Window * screen; 
SDL_Renderer * sdlRenderer; 
SDL_Texture * sdlTexture; 
SDL_Rect sdlRect; 
SDL_Thread * video_tid; 
SDL_Event event; 

Struct SwsContext * img_convert_ctx; 
DLG CRTSPPlayerDlg *=(CRTSPPlayerDlg *) lpParam; 

The static AVInputFormat * file_iformat; 
AVFormatContext * IC=NULL; 
* * opts AVDictionary; 
AVDictionaryEntry * t; 

Av_register_all (); 
Avformat_network_init (); 
AVCodec * pACodec=avcodec_find_decoder (AV_CODEC_ID_H264); 
PCodecCtx=NULL; 
PCodecCtx=avcodec_alloc_context3 (pACodec); 
PCodecCtx - & gt; Codec_type=AVMEDIA_TYPE_VIDEO; 
PCodecCtx - & gt; Pix_fmt=PIX_FMT_YUV420P; 
PCodecCtx - & gt; Width=1920; 
PCodecCtx - & gt; Height=1080; 

If (avcodec_open2 (pCodecCtx pACodec, NULL) & lt; 0) 
{
AfxMessageBox (" Could not open the codec. \ n "); 
return -1; 
} 

PFrame=av_frame_alloc (); 
PFrameYUV=av_frame_alloc (); 
Out_buffer=(uint8_t *) av_malloc (avpicture_get_size (PIX_FMT_YUV420P pCodecCtx - & gt; Width, pCodecCtx - & gt; Height)); 
Avpicture_fill ((AVPicture *) pFrameYUV out_buffer, PIX_FMT_YUV420P, pCodecCtx - & gt; Width, pCodecCtx - & gt; Height); 

Img_convert_ctx=sws_getContext (pCodecCtx - & gt; Width, pCodecCtx - & gt; Height, pCodecCtx - & gt; Pix_fmt, 
PCodecCtx - & gt; Width, pCodecCtx - & gt; Height, PIX_FMT_YUV420P SWS_BICUBIC, NULL, NULL, NULL); 


If (SDL_Init (SDL_INIT_VIDEO | SDL_INIT_TIMER)) 
{
AfxMessageBox (" Could not initialize the SDL \ n "); 
return -1; 
} 
//SDL 2.0 Support for multiple Windows 
Screen_w=pCodecCtx - & gt; Width; 
Screen_h=pCodecCtx - & gt; Height; 

//===========================================
//display on the MFC controls 
- screen=SDL_CreateWindowFrom (DLG & gt; GetDlgItem (IDC_SCREEN) - & gt; GetSafeHwnd ()); 
//===========================================
if(! Screen) 
{
AfxMessageBox (" SDL: could not create Windows - the exiting \ n "); 
return -1; 
} 
SdlRenderer=SDL_CreateRenderer (screen, 1, 0); 
//IYUV: Y + U + V (3 planes) 
//YV12: Y + V + U (3 planes) 
SdlTexture=SDL_CreateTexture (sdlRenderer SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, pCodecCtx - & gt; Width, pCodecCtx - & gt; Height); 

SdlRect. X=0; 
SdlRect. Y=0; 
SdlRect. W=screen_w; 
SdlRect. H=screen_h; 

Video_tid=SDL_CreateThread (sfp_refresh_thread, NULL, NULL); 
//-- -- -- -- -- -- -- -- -- -- -- -- SDL End -- -- -- -- -- -- -- -- -- -- -- -- 
//the Event Loop 
Av_init_packet (& amp; Packet); 
Char dateBuf [DUMMY_SINK_RECEIVE_BUFFER_SIZE]=""; 
For (;; ) 
{
//Wait 
SDL_WaitEvent (& amp; The event); 
If (event. Type==SFM_REFRESH_EVENT) 
{
//-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
Memset (dateBuf, 0, sizeof (dateBuf)); 
Int len=DLG - & gt; Read (dateBuf, 1); 
If (len==0) 
{
If (thread_exit==1) 
{
break; 
} 
Sleep (20); 
continue; 
} 
Packet data=https://bbs.csdn.net/topics/(uint8_t *) dateBuf; 
Packet. Size=len; 
Ret=avcodec_decode_video2 (pCodecCtx pFrame, & amp; Got_picture, & amp; Packet); 
If (ret & lt; 0) 
{
continue; 
AfxMessageBox (" Decode Error. \ n "); 
return -1; 
} 
If (got_picture) 
{
Const sws_scale (img_convert_ctx, (const uint8_t * *) pFrame - & gt; Data, pFrame - & gt; Linesize, 0, pCodecCtx - & gt; Height, pFrameYUV - & gt; The data, pFrameYUV - & gt; Linesize); 
SDL_UpdateTexture (sdlTexture, NULL, pFrameYUV - & gt; Data [0], pFrameYUV - & gt; Linesize [0]); 
SDL_RenderClear (sdlRenderer); 
SDL_RenderCopy (sdlRenderer sdlTexture, NULL, NULL); 
SDL_RenderPresent (sdlRenderer); 
} 
Av_free_packet (& amp; Packet); 
} 
Else if (event type==SDL_QUIT) 
{
Thread_exit=1; 
} 
Else if (event type==SFM_BREAK_EVENT) 
{
break; 
} 

} 

Sws_freeContext (img_convert_ctx); 
SDL_DestroyWindow (screen);//this function will block the 
SDL_DestroyRenderer (sdlRenderer); 
SDL_DestroyTexture (sdlTexture); 
SDL_Quit ();//this function will block the 
DLG - & gt; GetDlgItem (IDC_SCREEN) - & gt; ShowWindow (SW_SHOWNORMAL); 
Av_free (out_buffer); 
Av_frame_free (& amp; PFrameYUV); 
Av_frame_free (& amp; PFrame); 
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