Fixed bug 3770 - XStoreColor returns zero on failure

Thorsten Otto The fix done in http://hg.libsdl.org/SDL/rev/3665bc284271 is wrong. The current code returns -1 if the calls *succeeds*, and does not call XSync(). The outcome of this is that the whole screen turns black when trying to open a 640x480x8 window on a true-color display (short example attached). I suggest to add the attached patch to fix this (yes i know that the 1.2 branch is obsolete, but the faulty patch causes really bad behaviour for a very common scenario).
libsdl-org · Aug 28, 2017 · 8c86953 · 8c86953
1 parent 095451b
commit 8c86953
Showing 1 changed file with 5 additions and 4 deletions.
diff --git a/src/video/x11/SDL_x11video.c b/src/video/x11/SDL_x11video.c
@@ -1462,7 +1462,7 @@ int X11_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors)
 
 int X11_SetGammaRamp(_THIS, Uint16 *ramp)
 {
-	int i, ncolors;
+	int i, result, ncolors;
 	XColor xcmap[256];
 
 	/* See if actually setting the gamma is supported */
@@ -1481,12 +1481,13 @@ int X11_SetGammaRamp(_THIS, Uint16 *ramp)
 		xcmap[i].blue  = ramp[2*256+c];
 		xcmap[i].flags = (DoRed|DoGreen|DoBlue);
 	}
-	if ( XStoreColors(GFX_Display, SDL_XColorMap, xcmap, ncolors) != 0 ) {
+	result = 0;
+	if ( XStoreColors(GFX_Display, SDL_XColorMap, xcmap, ncolors) == False ) {
 		SDL_SetError("Setting gamma correction failed");
-		return(-1);
+		result = -1;
 	}
 	XSync(GFX_Display, False);
-	return(0);
+	return result;
 }
 
 /* Note:  If we are terminated, this could be called in the middle of