my previous version was wrong; this one is right

[unix-history] / usr / src / lib / libc / string / strncat.c

diff --git a/usr/src/lib/libc/string/strncat.c b/usr/src/lib/libc/string/strncat.c
index f88d8cd..db04e66 100644 (file)
--- a/usr/src/lib/libc/string/strncat.c
+++ b/usr/src/lib/libc/string/strncat.c
@@ -1,25 +1,42 @@
-/* @(#)strncat.c       4.1 (Berkeley) %G% */
-/*
- * Concatenate s2 on the end of s1.  S1's space must be large enough.
- * At most n characters are moved.
- * Return s1.
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * %sccs.include.redist.c%

  */
 
  */
 

+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)strncat.c  5.6 (Berkeley) %G%";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/cdefs.h>
+#include <string.h>
+
+/*
+ * Concatenate src on the end of dst.  At most strlen(dst)+n+1 bytes
+ * are written at dst (at most n+1 bytes being appended).  Return dst.
+ */

 char *
 char *

-strncat(s1, s2, n)
-register char *s1, *s2;
-register n;
+strncat(dst, src, n)
+       char *dst;
+       const char *src;
+       register size_t n;

 {
 {

-       register char *os1;
+       if (n != 0) {
+               register char *d = dst;
+               register const char *s = src;

 
 

-       os1 = s1;
-       while (*s1++)
-               ;
-       --s1;
-       while (*s1++ = *s2++)
-               if (--n < 0) {
-                       *--s1 = '\0';
-                       break;
-               }
-       return(os1);
+               while (*d != 0)
+                       d++;
+               do {
+                       if ((*d = *s++) == 0)
+                               break;
+                       d++;
+               } while (--n != 0);
+               *d = 0;
+       }
+       return (dst);

 }
 }