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lib/uuid-common/src/get_uptime_ms.cpp

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+/*
+ * uuid-common - Microcontroller common utilities
+ * Copyright 2019  Simon Arlott
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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 <uuid/common.h>
+
+#include <Arduino.h>
+
+namespace uuid {
+
+uint64_t get_uptime_ms() {
+    static uint32_t high_millis = 0;
+    static uint32_t low_millis  = 0;
+
+    uint32_t now_millis = ::millis();
+
+    if (now_millis < low_millis) {
+        high_millis++;
+    }
+
+    low_millis = now_millis;
+
+    return ((uint64_t)high_millis << 32) | low_millis;
+}
+
+} // namespace uuid