1 files changed, 68 insertions, 0 deletions
diff --git a/src/uscxml/concurrency/Timer.h b/src/uscxml/concurrency/Timer.h
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+++ b/src/uscxml/concurrency/Timer.h
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+// Copyright 2013 Alex Reece.
+//
+// A cross platform monotonic timer.
+
+// see https://github.com/awreece/monotonic_timer
+
+#ifndef MONOTONIC_TIMER_H_
+#define MONOTONIC_TIMER_H_
+
+// Returns seconds since some unspecified start time (guaranteed to be
+// monotonicly increasing).
+
+// Copyright 2015 Stefan Radomski.
+
+namespace uscxml {
+
+class USCXML_API Timer {
+public:
+    
+    static double monotonic_seconds();
+
+    Timer() {
+        invocations = 0;
+        elapsed = 0;
+    }
+    
+    void start() {
+        if (invocations == 0) {
+            started = monotonic_seconds();
+        }
+        invocations++;
+    }
+
+    void stop() {
+        if (invocations == 0)
+            return;
+        
+        invocations--;
+        if (invocations == 0) {
+            elapsed += monotonic_seconds() - started;
+        }
+    }
+
+    ~Timer() {
+    }
+    double elapsed;
+
+protected:
+    size_t invocations;
+    double started;
+};
+    
+class USCXML_API Measurement {
+public:
+    Measurement(Timer* timer) : timer(timer) {
+        timer->start();
+    }
+
+    ~Measurement() {
+        timer->stop();
+    }
+
+protected:
+    Timer* timer;
+};
+
+}
+#endif  // MONOTONIC_TIMER_H_