add strcpy implementation

klibc/src/string.c

@@ -106,3 +106,18 @@ int strcmp(const char *s1, const char *s2) {
     return d;
 }
 
+char *strncpy(char *dst, const char *src, size_t n) {
+    char *q = dst;
+    const char *p = src;
+    char ch;
+
+    while (n) {
+        n--;
+        *q++ = ch = *p++;
+        if (!ch) break;
+    }
+
+    memset(q, 0, n);
+
+    return dst;
+}