erpt: reimplement the sysmodule (#875)

* erpt: reimplement the sysmodule

* fatal: update for latest bindings

* erpt: amend logic for culling orphan attachments

libraries/libstratosphere/source/time/time_standard_user_system_clock.cpp

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2019-2020 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/>.
+ */
+#include <stratosphere.hpp>
+
+namespace ams::time {
+
+    Result StandardUserSystemClock::GetCurrentTime(PosixTime *out) {
+        static_assert(sizeof(*out) == sizeof(u64));
+        return ::timeGetCurrentTime(::TimeType_UserSystemClock, reinterpret_cast<u64 *>(out));
+    }
+
+    StandardUserSystemClock::time_point StandardUserSystemClock::now() {
+        PosixTime posix_time = {};
+        if (R_FAILED(GetCurrentTime(std::addressof(posix_time)))) {
+            posix_time.value = 0;
+        }
+
+        return time_point(duration(posix_time.value));
+    }
+
+    std::time_t StandardUserSystemClock::to_time_t(const StandardUserSystemClock::time_point &t) {
+        return static_cast<std::time_t>(std::chrono::duration_cast<std::chrono::seconds>(t.time_since_epoch()).count());
+    }
+
+    StandardUserSystemClock::time_point StandardUserSystemClock::from_time_t(std::time_t t) {
+        return time_point(duration(t));
+    }
+
+    /* TODO: Result StandardUserSystemClock::GetSystemClockContext(SystemClockContext *out); */
+
+}