util: move T(V)SNPrintf from kernel to util

libraries/libvapours/include/vapours/util/util_format_string.hpp

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <vapours/common.hpp>
+#include <vapours/assert.hpp>
+
+namespace ams::util {
+
+    int SNPrintf(char *dst, size_t dst_size, const char *fmt, ...);
+    int VSNPrintf(char *dst, size_t dst_size, const char *fmt, std::va_list vl);
+
+    int TSNPrintf(char *dst, size_t dst_size, const char *fmt, ...);
+    int TVSNPrintf(char *dst, size_t dst_size, const char *fmt, std::va_list vl);
+
+}