ceph/src/jaegertracing/opentelemetry-cpp/third_party/prometheus-cpp/core/src/gauge.cc

   1 #include "prometheus/gauge.h"
   2
   3 #include <ctime>
   4
   5 namespace prometheus {
   6
   7 Gauge::Gauge(const double value) : value_{value} {}
   8
   9 void Gauge::Increment() { Increment(1.0); }
  10
  11 void Gauge::Increment(const double value) { Change(value); }
  12
  13 void Gauge::Decrement() { Decrement(1.0); }
  14
  15 void Gauge::Decrement(const double value) { Change(-1.0 * value); }
  16
  17 void Gauge::Set(const double value) { value_.store(value); }
  18
  19 void Gauge::Change(const double value) {
  20   // C++ 20 will add std::atomic::fetch_add support for floating point types
  21   auto current = value_.load();
  22   while (!value_.compare_exchange_weak(current, current + value)) {
  23     // intentionally empty block
  24   }
  25 }
  26
  27 void Gauge::SetToCurrentTime() {
  28   const auto time = std::time(nullptr);
  29   Set(static_cast<double>(time));
  30 }
  31
  32 double Gauge::Value() const { return value_; }
  33
  34 ClientMetric Gauge::Collect() const {
  35   ClientMetric metric;
  36   metric.gauge.value = Value();
  37   return metric;
  38 }
  39
  40 }  // namespace prometheus