screen: added error handling to prevent this module from failing silently

modules/access/screen/mac.c

@@ -87,6 +87,8 @@ int screen_InitCapture( demux_t *p_demux )
     CGLPixelFormatObj pix;
     GLint npix;
     GLint viewport[4];
+    GLuint displayMask;
+    CGLError returnedError;
 
     p_sys->p_data = p_data =
         ( screen_data_t * )malloc( sizeof( screen_data_t ) );
@@ -96,12 +98,25 @@ int screen_InitCapture( demux_t *p_demux )
     attribs[2] = CGDisplayIDToOpenGLDisplayMask( CGMainDisplayID() );
     attribs[3] = 0;
 
-    CGLChoosePixelFormat( attribs, &pix, &npix );
-    CGLCreateContext( pix, NULL, &( p_data->screen ) );
-    CGLDestroyPixelFormat( pix );
+    returnedError = CGLChoosePixelFormat( attribs, &pix, &npix );
+    if (returnedError)
+        goto errorHandling;
 
-    CGLSetCurrentContext( p_data->screen );
-    CGLSetFullScreen( p_data->screen );
+    returnedError = CGLCreateContext( pix, NULL, &( p_data->screen ) );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLDestroyPixelFormat( pix );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLSetCurrentContext( p_data->screen );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLSetFullScreen( p_data->screen );
+    if (returnedError)
+        goto errorHandling;
 
     glGetIntegerv( GL_VIEWPORT, viewport );
 
@@ -124,15 +139,28 @@ int screen_InitCapture( demux_t *p_demux )
     attribs [2] = 32;
     attribs [3] = 0;
 
-    CGLChoosePixelFormat( attribs, &pix, &npix );
-    CGLCreateContext( pix, NULL, &( p_data->scaled ) );
-    CGLDestroyPixelFormat( pix );
+    returnedError = CGLChoosePixelFormat( attribs, &pix, &npix );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLCreateContext( pix, NULL, &( p_data->scaled ) );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLDestroyPixelFormat( pix );
+    if (returnedError)
+        goto errorHandling;
+
+    returnedError = CGLSetCurrentContext( p_data->scaled );
+    if (returnedError)
+        goto errorHandling;
 
-    CGLSetCurrentContext( p_data->scaled );
     p_data->scaled_image = ( char * )malloc( p_data->dest_width
                                           * p_data->dest_height * 4 );
-    CGLSetOffScreen( p_data->scaled, p_data->dest_width, p_data->dest_height,
-                     p_data->dest_width * 4, p_data->scaled_image );
+#warning FIXME: CGLSetOffScreen is no longer supported in the future!
+    returnedError = CGLSetOffScreen( p_data->scaled, p_data->dest_width, p_data->dest_height, p_data->dest_width * 4, p_data->scaled_image );
+    if (returnedError)
+        goto errorHandling;
 
     es_format_Init( &p_sys->fmt, VIDEO_ES, VLC_CODEC_RGB32 );
 
@@ -164,6 +192,10 @@ int screen_InitCapture( demux_t *p_demux )
     CGSNewConnection( NULL, &( p_data->connection ) );
 
     return VLC_SUCCESS;
+
+    errorHandling:
+    msg_Err( p_demux, "Core OpenGL failure: %s", CGLErrorString( returnedError ) );
+    return VLC_EGENERIC;
 }
 
 int screen_CloseCapture( demux_t *p_demux )