Import changeset

strings/bzero.c

@@ -0,0 +1,67 @@
+/*  File   : bzero.c
+    Author : Richard A. O'Keefe.
+	     Michael Widenius;	ifdef MC68000
+    Updated: 23 April 1984
+    Defines: bzero()
+
+    bzero(dst, len) moves "len" 0 bytes to "dst".
+    Thus to clear a disc buffer to 0s do bzero(buffer, BUFSIZ).
+
+    Note: the "b" routines are there to exploit certain VAX order codes,
+    The asm code is presented for your interest and amusement.
+*/
+
+#ifndef BSD_FUNCS
+#include "strings.h"
+
+#ifdef bzero
+#undef bzero					/* remove macro */
+#endif
+
+#if VaxAsm
+
+static void _bzero64 _A((char *dst,int	len));
+
+void bzero(dst, len)
+char *dst;
+uint len;
+{
+  while ((int) len >= 64*K)
+  {
+    _bzero64(dst, 64*K-1);
+    dst += 64*K-1;
+    len -= 64*K-1;
+  }
+  _bzero64(dst, len);
+}
+
+_bzero64(dst, len)
+char *dst;
+int  len;
+{
+  asm("movc5 $0,*4(ap),$0,8(ap),*4(ap)");
+}
+
+#else
+
+#if defined(MC68000) && defined(DS90)
+
+void bzero(dst, len)
+char *dst;
+uint len;
+{
+  bfill(dst,len,0);				/* This is very optimized ! */
+} /* bzero */
+
+#else
+
+void bzero(dst, len)
+register char *dst;
+register uint len;
+{
+  while (len-- != 0) *dst++ = 0;
+} /* bzero */
+
+#endif
+#endif
+#endif /* BSD_FUNCS */