X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=klibc%2Fklibc%2Fstrncat.c;h=0dd9deb984f1323874d64ef8fb5f0d11e8273387;hb=a0622777688ad84ef3d789e0171cfb0ca3dc21d2;hp=99d957594cfd07507d800edd867d06dc7625a285;hpb=a41a0e28c2ba0abf99b5e7ea17645ae0e4f05758;p=elogind.git

diff --git a/klibc/klibc/strncat.c b/klibc/klibc/strncat.c
index 99d957594..0dd9deb98 100644
--- a/klibc/klibc/strncat.c
+++ b/klibc/klibc/strncat.c
@@ -3,9 +3,23 @@
  */
 
 #include <string.h>
+#include <klibc/compiler.h>
 
 char *strncat(char *dst, const char *src, size_t n)
 {
-  strncpy(strchr(dst, '\0'), src, n);
+  char *q = strchr(dst, '\0');
+  const char *p = src;
+  char ch;
+  size_t nn = q-dst;
+
+  if ( __likely(nn <= n) )
+    n -= nn;
+
+  while (n--) {
+    *q++ = ch = *p++;
+    if ( !ch )
+      break;
+  }
+
   return dst;
 }