VESA: Minor cleanups

Minor cleanups for clarity

diff --git a/com32/lib/sys/vesa/initvesa.c b/com32/lib/sys/vesa/initvesa.c
index 98888d3..0ad882b 100644 (file)
--- a/com32/lib/sys/vesa/initvesa.c
+++ b/com32/lib/sys/vesa/initvesa.c
@@ -75,13 +75,14 @@ static int vesacon_paged_mode_ok(const struct vesa_mode_info *mi)
 {
   int i;
 
+  if (!is_power_of_2(mi->win_size) ||
+      !is_power_of_2(mi->win_grain) ||
+      mi->win_grain > mi->win_size)
+    return 0;                  /* Impossible... */
+
   for (i = 0; i < 2; i++) {
-    if ((mi->win_attr[i] & 0x05) == 0x05 &&
-       mi->win_seg[i] &&
-       is_power_of_2(mi->win_size) &&
-       is_power_of_2(mi->win_grain) &&
-       mi->win_grain <= mi->win_size)
-      return 1;                        /* We can deal with this... */
+    if ((mi->win_attr[i] & 0x05) == 0x05 && mi->win_seg[i])
+      return 1;                        /* Usable window */
   }
 
   return 0;                    /* Nope... */
@@ -121,7 +122,8 @@ static int vesacon_set_mode(void)
   /* Copy general info */
   memcpy(&__vesa_info.gi, gi, sizeof *gi);
 
-  /* Search for a 640x480 32-bit linear frame buffer mode */
+  /* Search for a 640x480 mode with a suitable color and memory model... */
+
   mode_ptr = GET_PTR(gi->video_mode_ptr);
   bestmode = 0;
   bestpxf  = PXF_NONE;

diff --git a/com32/lib/sys/vesa/screencpy.c b/com32/lib/sys/vesa/screencpy.c
index 779fe5d..4972eea 100644 (file)
--- a/com32/lib/sys/vesa/screencpy.c
+++ b/com32/lib/sys/vesa/screencpy.c
@@ -80,13 +80,14 @@ static void set_window_pos(size_t win_pos)
 {
   static com32sys_t ireg;
 
+  wi.win_pos = win_pos;
+
   if (wi.win_num < 0)
-    return;
+    return;                    /* This should never happen... */
 
   ireg.eax.w[0] = 0x4F05;
   ireg.ebx.b[0] = wi.win_num;
   ireg.edx.w[0] = win_pos >> wi.win_gshift;
-  wi.win_pos = win_pos;
 
   __intcall(0x10, &ireg, NULL);
 }