[src/trunk]: src/sys/dev/rasops rasops_do_cursor():

[macallan <macallan%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/7f2abb47e519
branches:  trunk
changeset: 446298:7f2abb47e519
user:      macallan <macallan%NetBSD.org@localhost>
date:      Thu Nov 29 23:44:50 2018 +0000

description:
rasops_do_cursor():
- simplify & sanitize the unaligned case
- use only 32bit accesses
... no longer crash with odd sized fonts in 8bit

diffstat:

 sys/dev/rasops/rasops.c |  55 +++++++++++++++++-------------------------------
 1 files changed, 20 insertions(+), 35 deletions(-)

diffs (98 lines):

diff -r b8690ecb8280 -r 7f2abb47e519 sys/dev/rasops/rasops.c
--- a/sys/dev/rasops/rasops.c   Thu Nov 29 23:18:40 2018 +0000
+++ b/sys/dev/rasops/rasops.c   Thu Nov 29 23:44:50 2018 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: rasops.c,v 1.77 2017/06/01 02:45:11 chs Exp $ */
+/*      $NetBSD: rasops.c,v 1.78 2018/11/29 23:44:50 macallan Exp $    */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rasops.c,v 1.77 2017/06/01 02:45:11 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rasops.c,v 1.78 2018/11/29 23:44:50 macallan Exp $");
 
 #include "opt_rasops.h"
 #include "rasops_glue.h"
@@ -995,7 +995,7 @@
 rasops_do_cursor(struct rasops_info *ri)
 {
        int full1, height, cnt, slop1, slop2, row, col;
-       u_char *dp, *rp, *hrp, *hp, tmp = 0;
+       u_char *dp, *rp, *hrp, *hp;
 
        hrp = hp = NULL;
 
@@ -1055,33 +1055,26 @@
                        }
                }
        } else {
-               uint16_t tmp16;
-               uint32_t tmp32;
-               /* XXX this is stupid.. use masks instead */
+               uint32_t tmp32, msk1, msk2;
+
+               msk1 = be32toh(0xffffffff >> (32 - (8 * slop1)));
+               msk2 = be32toh(0xffffffff << (32 - (8 * slop2)));
+
                while (height--) {
-                       dp = rp;
+                       dp = (u_char *)((uintptr_t)rp & ~3);
                        rp += ri->ri_stride;
                        if (ri->ri_hwbits) {
-                               hp = hrp;
+                               hp = (u_char *)((uintptr_t)hrp & ~3);
                                hrp += ri->ri_stride;
                        }
 
-                       if (slop1 & 1) {
-                               tmp = *dp ^ ~0;
-                               *dp = tmp;
-                               dp++;
+                       if (msk1 != 0) {
+                               tmp32 = *(int32_t *)dp ^ msk1;
+                               *(uint32_t *)dp = tmp32;
+                               dp += 4;
                                if (ri->ri_hwbits) {
-                                       *hp++ = tmp;
-                               }
-                       }
-
-                       if (slop1 & 2) {
-                               tmp16 = *(int16_t *)dp ^ ~0;
-                               *(uint16_t *)dp = tmp16;
-                               dp += 2;
-                               if (ri->ri_hwbits) {
-                                       *(int16_t *)hp = tmp16;
-                                       hp += 2;
+                                       *(int32_t *)hp = tmp32;
+                                       hp += 4;
                                }
                        }
 
@@ -1095,19 +1088,11 @@
                                }
                        }
 
-                       if (slop2 & 1) {
-                               tmp = *dp ^ ~0;
-                               *dp = tmp;
-                               dp++;
+                       if (msk2 != 0) {
+                               tmp32 = *(int32_t *)dp ^ msk2;
+                               *(uint32_t *)dp = tmp32;
                                if (ri->ri_hwbits)
-                                       *hp++ = tmp;
-                       }
-
-                       if (slop2 & 2) {
-                               tmp16 = *(int16_t *)dp ^ ~0;
-                               *(uint16_t *)dp = tmp16;
-                               if (ri->ri_hwbits)
-                                       *(int16_t *)hp = tmp16;
+                                       *(int32_t *)hp = tmp32;
                        }
                }
        }