Putting in the null byte "manually", and only when using UTF-8.

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@5347 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

ChangeLog

+2015-08-08  Benno Schulenberg  <bensberg@justemail.net>
+	* src/winio.c (display_string): For some reason the reallocation done
+	by null_at() messes things up.  So put in the null byte "manually".
+	This is a fix -- or workaround -- for Savannah bug #45718.
+
 2015-08-06  Benno Schulenberg  <bensberg@justemail.net>
 	* src/nano.c (main): For --enable-debug builds, let malloc() help
 	to find initialization failures and uses-after-free.  Suggested by

src/winio.c

@@ -1999,10 +1999,13 @@ char *display_string(const char *buf, size_t start_col, size_t len, bool
 	    char *nctrl_buf_mb = charalloc(mb_cur_max());
 	    int nctrl_buf_mb_len, i;
 
+#ifdef ENABLE_UTF8
 	    /* Make sure an invalid sequence-starter byte is properly
 	     * terminated, so that it doesn't pick up lingering bytes
 	     * of any previous content. */
-	    null_at(&buf_mb, buf_mb_len);
+	    if (using_utf8() && buf_mb_len == 1)
+		buf_mb[1] = '\0';
+#endif
 
 	    nctrl_buf_mb = mbrep(buf_mb, nctrl_buf_mb,
 		&nctrl_buf_mb_len);