Use ints for the calculations rather than u_char, they could end up

signed.

diff --git a/usr.bin/tmux/colour.c b/usr.bin/tmux/colour.c
index 8dc65e0..695e3cd 100644 (file)
--- a/usr.bin/tmux/colour.c
+++ b/usr.bin/tmux/colour.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: colour.c,v 1.10 2015/06/05 22:33:39 nicm Exp $ */
+/* $OpenBSD: colour.c,v 1.11 2015/06/05 22:50:27 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -313,6 +313,7 @@ colour_find_rgb(u_char r, u_char g, u_char b)
 {
        struct colour_rgb       rgb = { .r = r, .g = g, .b = b }, *found;
        u_int                   distance, lowest, colour, i;
+       int                     dr, dg, db;
 
        found = bsearch(&rgb, colour_to_256, nitems(colour_to_256),
            sizeof colour_to_256[0], colour_cmp_rgb);
@@ -322,11 +323,11 @@ colour_find_rgb(u_char r, u_char g, u_char b)
        colour = 16;
        lowest = UINT_MAX;
        for (i = 0; i < 240; i++) {
-               r = colour_from_256[i].r - rgb.r;
-               g = colour_from_256[i].g - rgb.g;
-               b = colour_from_256[i].b - rgb.b;
+               dr = (int)colour_from_256[i].r - r;
+               dg = (int)colour_from_256[i].g - g;
+               db = (int)colour_from_256[i].b - b;
 
-               distance = r * r + g * g + b * b;
+               distance = dr * dr + dg * dg + db * db;
                if (distance < lowest) {
                        lowest = distance;
                        colour = 16 + i;