From b3a2d6bfde0fe677101aa0fbabcdcedae9fa5e5a Mon Sep 17 00:00:00 2001
From: Bart Oldeman <bart@dosemu.org>
Date: Mon, 24 May 2004 18:39:49 +0000
Subject: [PATCH] Reorganized GetBiosKey a bit -- inlining GetBiosTime saves a
 slight amount of code, converted timeout < 0 to a blocking read instead of
 polling.

git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@958 6ac86273-5f31-0410-b378-82cca8765d1b
---
 kernel/config.c | 30 ++++++++++--------------------
 1 file changed, 10 insertions(+), 20 deletions(-)

diff --git a/kernel/config.c b/kernel/config.c
index 6397131..6a30d0b 100644
--- a/kernel/config.c
+++ b/kernel/config.c
@@ -741,10 +741,7 @@ STATIC struct table * LookUp(struct table *p, BYTE * token)
             0x..LL : asciicode in lower half
 */
 
-STATIC ULONG GetBiosTime(VOID)
-{
-  return *(ULONG FAR *) (MK_FP(0x40, 0x6c));
-}
+#define GetBiosTime() peekl(0, 0x46c)
 
 UWORD GetBiosKey(int timeout)
 {
@@ -752,26 +749,19 @@ UWORD GetBiosKey(int timeout)
 
   ULONG startTime = GetBiosTime();
 
-  for (;;)
+  if (timeout >= 0) do
   {
     r.a.x = 0x0100;             /* are there keys available ? */
     init_call_intr(0x16, &r);
-
-    if ((r.flags & 0x40) == 0)  /* yes - fetch and return     */
-    {
-      r.a.x = 0x0000;
-      init_call_intr(0x16, &r);
-
-      return r.a.x;
-    }
-
-    if (timeout < 0)
-      continue;
-
-    if (GetBiosTime() - startTime >= (unsigned)timeout * 18)
-      break;
+    if ((unsigned)(GetBiosTime() - startTime) >= timeout * 18u)
+      return 0xffff;
   }
-  return 0xffff;
+  while (r.flags & FLG_ZERO);
+
+  /* key available or blocking wait (timeout < 0): fetch it */
+  r.a.x = 0x0000;
+  init_call_intr(0x16, &r);
+  return r.a.x;
 }
 
 STATIC BOOL SkipLine(char *pLine)