(output_string): New function.

(internal_flush): Use output_string for faster screen update.
(internal_flush): Clear to end of line by writing a string of spaces.

1 files changed, 49 insertions, 6 deletions

diff --git a/src/msdos.c b/src/msdos.c
index 58733b418aa..154ee1501c5 100644
--- a/src/msdos.c
+++ b/src/msdos.c
@@ -809,6 +809,35 @@ visible_bell_3:
         popl  %eax");
 }
 
+/* At screen position (X,Y), output C characters from string S with
+   attribute A.  Do it fast!  */
+
+static void
+output_string (x, y, s, c, a)
+     int x, y, c;
+     unsigned char *s;
+     unsigned char a;
+{
+  char *t = (char *)ScreenPrimary + 2 * (x + ScreenCols () * y);
+  asm volatile
+    ("  movl   %1,%%eax
+        call   dosmemsetup
+        movl   %%eax,%%edi
+        movb   %0,%%ah
+        movl   %2,%%ecx
+        movl   %3,%%esi
+output_string1:
+        movb   (%%esi),%%al
+        movw   %%ax,%%gs:(%%edi)
+        addl   $2,%%edi
+        incl   %%esi
+        decl   %%ecx
+        jne    output_string1"
+     : /* no output */
+     : "m" (a), "g" (t), "g" (c), "g" (s)
+     : "%eax", "%ecx", /* "%gs",*/ "%esi", "%edi");
+}
+
 static int internal_terminal = 0;
 #undef fflush
 
@@ -816,10 +845,11 @@ int
 internal_flush (f)
      FILE *f;
 {
+  static char spaces[] = "                                                                                ";
   static int x;
   static int y;
-  char c, *cp;
-  int count, i;
+  unsigned char *cp, *cp0;
+  int count, i, j;
 
   if (internal_terminal && f == stdout)
     {
@@ -828,7 +858,7 @@ internal_flush (f)
       count = stdout->_ptr - stdout->_base;
       while (count > 0)
         {
-          switch (c = *cp++)
+          switch (*cp++)
             {
             case 27:
               switch (*cp++)
@@ -852,8 +882,17 @@ internal_flush (f)
                   count -= 2;
                   break;
                 case 'E':
-                  for (i = ScreenCols () - 1; i >= x; i--)
-                    ScreenPutChar (' ', ScreenAttrib, i, y);
+                  i = ScreenCols () - x;
+                  j = x;
+                  while (i >= sizeof spaces)
+                    {
+                      output_string (j, y, spaces, sizeof spaces,
+                                     ScreenAttrib);
+                      j += sizeof spaces;
+                      i -= sizeof spaces;
+                    }
+                  if (i > 0)
+                    output_string (j, y, spaces, i, ScreenAttrib);
                   count -= 2;
                   break;
                 case 'R':
@@ -889,8 +928,12 @@ internal_flush (f)
               count--;
               break;
             default:
-              ScreenPutChar (c, ScreenAttrib, x++, y);
+              cp0 = cp - 1;
               count--;
+              while (count > 0 && *cp >= ' ')
+                cp++, count--;
+              output_string (x, y, cp0, cp - cp0, ScreenAttrib);
+              x += (cp - cp0);
             }
         }
       fpurge (stdout);