ftp://ftp.uniovi.es/pub/X11R6/graphics/misc/lock/xscreensaver-1.22.tar.gz

[xscreensaver] / utils / fade.c

diff --git a/utils/fade.c b/utils/fade.c
index 8d4866907aa8d4ee10380677059405ea673cb9aa..170cd39e604fad7c6213e957255bc6375e7d46a3 100644 (file)
--- a/utils/fade.c
+++ b/utils/fade.c
@@ -17,14 +17,8 @@
 #include <X11/Xlib.h>
 #include <X11/Xos.h>
 
-#if __STDC__
-# define bcopy(from,to,size) memcpy((to),(from),(size))
-# define bzero(addr,size) memset((addr),0,(size))
-extern void screenhack_usleep (unsigned long);
-#else
+extern int get_visual_class ();
 extern void screenhack_usleep ();
-#endif
-
 #define usleep screenhack_usleep
 
 #define MAX_COLORS 4096
@@ -38,13 +32,23 @@ copy_colormap (dpy, cmap, into_cmap)
      Colormap cmap, into_cmap;
 {
   int i;
-  ncolors = CellsOfScreen (DefaultScreenOfDisplay (dpy));
+  Screen *screen = DefaultScreenOfDisplay (dpy);
+  Visual *visual = DefaultVisualOfScreen (screen);
+  Window window = RootWindowOfScreen (screen);
+  int vclass = get_visual_class (dpy, visual);
+
+  ncolors = CellsOfScreen (screen);
+
+  /* If this is a colormap on a mono visual, or one with insanely many
+     color cells, bug out. */
   if (ncolors <= 2 || ncolors > MAX_COLORS)
     return 0;
+  /* If this is a non-writable visual, bug out. */
+  if (vclass == StaticGray || vclass == StaticColor || vclass == TrueColor)
+    return 0;
+
   if (! into_cmap)
-    into_cmap = XCreateColormap (dpy, RootWindow (dpy, DefaultScreen (dpy)),
-                                DefaultVisual (dpy, DefaultScreen (dpy)),
-                                AllocAll);
+    into_cmap = XCreateColormap (dpy, window, visual, AllocAll);
   if (! cmap)
     cmap = DefaultColormap (dpy, DefaultScreen (dpy));
   for (i = 0; i < ncolors; i++)
@@ -87,7 +91,7 @@ fade_colormap (dpy, cmap, cmap2, seconds, ticks, out_p)
   for (i = 0; i < ncolors; i++)
     orig_colors [i].pixel = i;
   XQueryColors (dpy, cmap, orig_colors, ncolors);
-  bcopy (orig_colors, current_colors, ncolors * sizeof (XColor));
+  memcpy (current_colors, orig_colors, ncolors * sizeof (XColor));
 
   for (i = (out_p ? steps : 0);
        (out_p ? i > 0 : i < steps);
@@ -96,9 +100,9 @@ fade_colormap (dpy, cmap, cmap2, seconds, ticks, out_p)
       int j;
       for (j = 0; j < ncolors; j++)
        {
-         current_colors[j].red   = (int)orig_colors[j].red   * i / steps;
-         current_colors[j].green = (int)orig_colors[j].green * i / steps;
-         current_colors[j].blue  = (int)orig_colors[j].blue  * i / steps;
+         current_colors[j].red   = orig_colors[j].red   * i / steps;
+         current_colors[j].green = orig_colors[j].green * i / steps;
+         current_colors[j].blue  = orig_colors[j].blue  * i / steps;
        }
       XStoreColors (dpy, cmap2, current_colors, ncolors);
       XSync (dpy, False);