Check rfbGetScreen() return value everywhere.

This fixes a segfault when a server is invoked with the
'-help' commandline argument.

13 files changed, 28 insertions, 4 deletions

diff --git a/examples/backchannel.c b/examples/backchannel.c
index 7aa0fa1..c625753 100644
--- a/examples/backchannel.c
+++ b/examples/backchannel.c
@@ -107,6 +107,8 @@ int main(int argc,char** argv)
 	rfbRegisterProtocolExtension(&backChannelExtension);
 
 	server=rfbGetScreen(&argc,argv,400,300,8,3,4);
+	if(!server)
+	  return 0;
 	server->frameBuffer=(char*)malloc(400*300*4);
 	rfbInitServer(server);           
 	rfbRunEventLoop(server,-1,FALSE);
diff --git a/examples/camera.c b/examples/camera.c
index 7077790..58ab1c3 100644
--- a/examples/camera.c
+++ b/examples/camera.c
@@ -133,6 +133,8 @@ int main(int argc,char** argv)
   long usec;
   
   rfbScreenInfoPtr server=rfbGetScreen(&argc,argv,WIDTH,HEIGHT,8,3,BPP);
+  if(!server)
+    return 0;
   server->desktopName = "Live Video Feed Example";
   server->frameBuffer=(char*)malloc(WIDTH*HEIGHT*BPP);
   server->alwaysShared=(1==1);
diff --git a/examples/colourmaptest.c b/examples/colourmaptest.c
index e403164..20ea303 100644
--- a/examples/colourmaptest.c
+++ b/examples/colourmaptest.c
@@ -7,7 +7,8 @@ int main(int argc,char** argv)
   uint8_t bytes[256*3];
 
   rfbScreenInfoPtr server=rfbGetScreen(&argc,argv,256,256,8,1,1);
-
+  if(!server)
+    return 0;
   server->serverFormat.trueColour=FALSE;
   server->colourMap.count=256;
   server->colourMap.is16=FALSE;
diff --git a/examples/example.c b/examples/example.c
index 31bc38d..93fdf28 100644
--- a/examples/example.c
+++ b/examples/example.c
@@ -279,8 +279,9 @@ static void MakeRichCursor(rfbScreenInfoPtr rfbScreen)
 
 int main(int argc,char** argv)
 {
-  rfbScreenInfoPtr rfbScreen =
-    rfbGetScreen(&argc,argv,maxx,maxy,8,3,bpp);
+  rfbScreenInfoPtr rfbScreen = rfbGetScreen(&argc,argv,maxx,maxy,8,3,bpp);
+  if(!rfbScreen)
+    return 0;
   rfbScreen->desktopName = "LibVNCServer Example";
   rfbScreen->frameBuffer = (char*)malloc(maxx*maxy*bpp);
   rfbScreen->alwaysShared = TRUE;
diff --git a/examples/filetransfer.c b/examples/filetransfer.c
index ff4af11..2d03fe1 100644
--- a/examples/filetransfer.c
+++ b/examples/filetransfer.c
@@ -7,6 +7,8 @@
 int main(int argc,char** argv)
 {                                                                
   rfbScreenInfoPtr server=rfbGetScreen(&argc,argv,400,300,8,3,4);
+  if(!server)
+    return 0;
   server->frameBuffer=(char*)malloc(400*300*4);
   rfbRegisterTightVNCFileTransferExtension();
   rfbInitServer(server);           
diff --git a/examples/fontsel.c b/examples/fontsel.c
index 85d2624..15139dc 100644
--- a/examples/fontsel.c
+++ b/examples/fontsel.c
@@ -41,6 +41,9 @@ int main(int argc,char** argv)
   rfbScreenInfoPtr s=rfbGetScreen(&argc,argv,640,480,8,3,3);
   int i,j;
 
+  if(!s)
+    return 0;
+
   s->frameBuffer=(char*)malloc(640*480*3);
   rfbInitServer(s);
 
diff --git a/examples/mac.c b/examples/mac.c
index 2d335a4..1c85d73 100644
--- a/examples/mac.c
+++ b/examples/mac.c
@@ -455,6 +455,8 @@ ScreenInit(int argc, char**argv)
 			   CGDisplayPixelsHigh(kCGDirectMainDisplay),
 			   bitsPerSample,
 			   CGDisplaySamplesPerPixel(kCGDirectMainDisplay),4);
+  if(!rfbScreen)
+    exit(0);
   rfbScreen->serverFormat.redShift = bitsPerSample*2;
   rfbScreen->serverFormat.greenShift = bitsPerSample*1;
   rfbScreen->serverFormat.blueShift = 0;
diff --git a/examples/pnmshow.c b/examples/pnmshow.c
index 734155f..6ced92a 100644
--- a/examples/pnmshow.c
+++ b/examples/pnmshow.c
@@ -65,6 +65,8 @@ int main(int argc,char** argv)
 
   /* initialize data for vnc server */
   rfbScreen = rfbGetScreen(&argc,argv,paddedWidth,height,8,(bitsPerPixelInFile+7)/8,bytesPerPixel);
+  if(!rfbScreen)
+    return 0;
   if(argc>1)
     rfbScreen->desktopName = argv[1];
   else
diff --git a/examples/pnmshow24.c b/examples/pnmshow24.c
index a8d6c1d..81389d7 100644
--- a/examples/pnmshow24.c
+++ b/examples/pnmshow24.c
@@ -60,6 +60,8 @@ int main(int argc,char** argv)
 
   /* initialize data for vnc server */
   rfbScreen = rfbGetScreen(&argc,argv,paddedWidth,height,8,3,3);
+  if(!rfbScreen)
+    return 0;
   if(argc>1)
     rfbScreen->desktopName = argv[1];
   else
diff --git a/examples/simple.c b/examples/simple.c
index f6e94dc..6167d72 100644
--- a/examples/simple.c
+++ b/examples/simple.c
@@ -3,6 +3,8 @@
 int main(int argc,char** argv)
 {                                                                
   rfbScreenInfoPtr server=rfbGetScreen(&argc,argv,400,300,8,3,4);
+  if(!server)
+    return 0;
   server->frameBuffer=(char*)malloc(400*300*4);
   rfbInitServer(server);           
   rfbRunEventLoop(server,-1,FALSE);
diff --git a/examples/simple15.c b/examples/simple15.c
index faff4f7..a90988e 100644
--- a/examples/simple15.c
+++ b/examples/simple15.c
@@ -9,7 +9,8 @@ int main(int argc,char** argv)
   uint16_t* f;
                          
   rfbScreenInfoPtr server=rfbGetScreen(&argc,argv,400,300,5,3,2);
-
+  if(!server)
+    return 0;
   server->frameBuffer=(char*)malloc(400*300*2);
   f=(uint16_t*)server->frameBuffer;
   for(j=0;j<300;j++)
diff --git a/examples/vncev.c b/examples/vncev.c
index 9ebafc9..ba9441a 100644
--- a/examples/vncev.c
+++ b/examples/vncev.c
@@ -112,6 +112,8 @@ static enum rfbNewClientAction newclient(rfbClientPtr cl)
 int main(int argc,char** argv)
 {
    rfbScreenInfoPtr s=rfbGetScreen(&argc,argv,width,height,8,1,1);
+   if(!s)
+     return 0;
    s->colourMap.is16=FALSE;
    s->colourMap.count=2;
    s->colourMap.data.bytes=(unsigned char*)"\xd0\xd0\xd0\x30\x01\xe0";
diff --git a/examples/zippy.c b/examples/zippy.c
index d8a90d7..4f793a9 100644
--- a/examples/zippy.c
+++ b/examples/zippy.c
@@ -27,6 +27,8 @@ int main (int argc, char **argv)
 	  return 1;
 	  
         server = rfbGetScreen (&argc, argv, maxx, maxy, 8, 3, bpp);
+        if(!server)
+          return 0;
 	server->desktopName = "Zippy das wundersquirrel\'s VNC server";
 	server->frameBuffer = (char*)malloc(maxx*maxy*bpp);
 	server->alwaysShared = TRUE;