[SDK:CRT] Implement wcscpy_s() and wcscat_s()

SDK/CRT/STRING/wstr.c

@@ -26,7 +26,7 @@ wcslen (
     ptr = str;
     while (*ptr++);
 
-    return (const char*)ptr - (const char*)str - sizeof(wchar_t);
+    return ptr - str;
 }
 
 size_t
@@ -39,9 +39,12 @@ wcsnlen (
     size_t len;
 
     len = 0;
-    while (len < maxlen && str[len++]);
+    while (len < maxlen && *str) {
+        len++;
+        str++;
+    }
 
-    return len - sizeof(wchar_t);
+    return len;
 }
 
 int
@@ -127,3 +130,41 @@ wcsstr (
 
     return NULL;
 }
+
+wchar_t *
+wcscpy_s (
+    wchar_t *dest,
+    size_t maxlen,
+    const wchar_t *src
+    )
+
+{
+    for (size_t i = 0; i < maxlen; i++, src++) {
+        dest[i] = *src;
+
+        if (!*src) {
+            break;
+        }
+    }
+
+    return dest;
+}
+
+wchar_t *
+wcscat_s (
+    wchar_t *dest,
+    size_t maxlen,
+    const wchar_t *src
+    )
+
+{
+    for (size_t i = wcsnlen(dest, maxlen); i < maxlen; i++, src++) {
+        dest[i] = *src;
+
+        if (!*src) {
+            break;
+        }
+    }
+
+    return dest;
+}