client_examples/ppmtest.c

   1 /**
   2  * @example ppmtest.c
   3  * A simple example of an RFB client
   4  */
   5
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <time.h>
   9 #include <errno.h>
  10 #include <rfb/rfbclient.h>
  11
  12 static void PrintRect(rfbClient* client, int x, int y, int w, int h) {
  13         rfbClientLog("Received an update for %d,%d,%d,%d.\n",x,y,w,h);
  14 }
  15
  16 static void SaveFramebufferAsPPM(rfbClient* client, int x, int y, int w, int h) {
  17         static time_t t=0,t1;
  18         FILE* f;
  19         int i,j;
  20         rfbPixelFormat* pf=&client->format;
  21         int bpp=pf->bitsPerPixel/8;
  22         int row_stride=client->width*bpp;
  23
  24         /* save one picture only if the last is older than 2 seconds */
  25         t1=time(NULL);
  26         if(t1-t>2)
  27                 t=t1;
  28         else
  29                 return;
  30
  31         /* assert bpp=4 */
  32         if(bpp!=4 && bpp!=2) {
  33                 rfbClientLog("bpp = %d (!=4)\n",bpp);
  34                 return;
  35         }
  36
  37         f=fopen("framebuffer.ppm","wb");
  38         if(!f) {
  39                 rfbClientErr("Could not open framebuffer.ppm\n");
  40                 return;
  41         }
  42
  43         fprintf(f,"P6\n# %s\n%d %d\n255\n",client->desktopName,client->width,client->height);
  44         for(j=0;j<client->height*row_stride;j+=row_stride)
  45                 for(i=0;i<client->width*bpp;i+=bpp) {
  46                         unsigned char* p=client->frameBuffer+j+i;
  47                         unsigned int v;
  48                         if(bpp==4)
  49                                 v=*(unsigned int*)p;
  50                         else if(bpp==2)
  51                                 v=*(unsigned short*)p;
  52                         else
  53                                 v=*(unsigned char*)p;
  54                         fputc((v>>pf->redShift)*256/(pf->redMax+1),f);
  55                         fputc((v>>pf->greenShift)*256/(pf->greenMax+1),f);
  56                         fputc((v>>pf->blueShift)*256/(pf->blueMax+1),f);
  57                 }
  58         fclose(f);
  59 }
  60
  61 int
  62 main(int argc, char **argv)
  63 {
  64         rfbClient* client = rfbGetClient(8,3,4);
  65         time_t t=time(NULL);
  66
  67         if(argc>1 && !strcmp("-print",argv[1])) {
  68                 client->GotFrameBufferUpdate = PrintRect;
  69                 argv[1]=argv[0]; argv++; argc--;
  70         } else
  71                 client->GotFrameBufferUpdate = SaveFramebufferAsPPM;
  72
  73         /* The -listen option is used to make us a daemon process which listens for
  74            incoming connections from servers, rather than actively connecting to a
  75            given server. The -tunnel and -via options are useful to create
  76            connections tunneled via SSH port forwarding. We must test for the
  77            -listen option before invoking any Xt functions - this is because we use
  78            forking, and Xt doesn't seem to cope with forking very well. For -listen
  79            option, when a successful incoming connection has been accepted,
  80            listenForIncomingConnections() returns, setting the listenSpecified
  81            flag. */
  82
  83         if (!rfbInitClient(client,&argc,argv))
  84                 return 1;
  85
  86         /* TODO: better wait for update completion */
  87         while (time(NULL)-t<5) {
  88                 static int i=0;
  89                 fprintf(stderr,"\r%d",i++);
  90                 if(WaitForMessage(client,50)<0)
  91                         break;
  92                 if(!HandleRFBServerMessage(client))
  93                         break;
  94         }
  95
  96         rfbClientCleanup(client);
  97
  98         return 0;
  99 }
 100