1 files changed, 242 insertions, 0 deletions
diff --git a/toolkit/components/glean/bindings/private/TimingDistribution.cpp b/toolkit/components/glean/bindings/private/TimingDistribution.cpp
new file mode 100644
index 0000000000..f7a78165ae
--- /dev/null
+++ b/toolkit/components/glean/bindings/private/TimingDistribution.cpp
@@ -0,0 +1,242 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/glean/bindings/TimingDistribution.h"
+
+#include "mozilla/AppShutdown.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/ResultVariant.h"
+#include "mozilla/dom/GleanMetricsBinding.h"
+#include "mozilla/dom/ToJSValue.h"
+#include "mozilla/glean/bindings/HistogramGIFFTMap.h"
+#include "mozilla/glean/fog_ffi_generated.h"
+#include "nsJSUtils.h"
+#include "nsPrintfCString.h"
+#include "nsString.h"
+#include "js/PropertyAndElement.h"  // JS_DefineProperty
+
+namespace mozilla::glean {
+
+using MetricId = uint32_t;  // Same type as in api/src/private/mod.rs
+using MetricTimerTuple = std::tuple<MetricId, TimerId>;
+class MetricTimerTupleHashKey : public PLDHashEntryHdr {
+ public:
+  using KeyType = const MetricTimerTuple&;
+  using KeyTypePointer = const MetricTimerTuple*;
+
+  explicit MetricTimerTupleHashKey(KeyTypePointer aKey) : mValue(*aKey) {}
+  MetricTimerTupleHashKey(MetricTimerTupleHashKey&& aOther)
+      : PLDHashEntryHdr(std::move(aOther)), mValue(aOther.mValue) {}
+  ~MetricTimerTupleHashKey() = default;
+
+  KeyType GetKey() const { return mValue; }
+  bool KeyEquals(KeyTypePointer aKey) const {
+    return std::get<0>(*aKey) == std::get<0>(mValue) &&
+           std::get<1>(*aKey) == std::get<1>(mValue);
+  }
+
+  static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
+  static PLDHashNumber HashKey(KeyTypePointer aKey) {
+    // Chosen because this is how nsIntegralHashKey does it.
+    return HashGeneric(std::get<0>(*aKey), std::get<1>(*aKey));
+  }
+  enum { ALLOW_MEMMOVE = true };
+
+ private:
+  const MetricTimerTuple mValue;
+};
+
+using TimerToStampMutex =
+    StaticDataMutex<UniquePtr<nsTHashMap<MetricTimerTupleHashKey, TimeStamp>>>;
+static Maybe<TimerToStampMutex::AutoLock> GetTimerIdToStartsLock() {
+  static TimerToStampMutex sTimerIdToStarts("sTimerIdToStarts");
+  auto lock = sTimerIdToStarts.Lock();
+  // GIFFT will work up to the end of AppShutdownTelemetry.
+  if (AppShutdown::IsInOrBeyond(ShutdownPhase::XPCOMWillShutdown)) {
+    return Nothing();
+  }
+  if (!*lock) {
+    *lock = MakeUnique<nsTHashMap<MetricTimerTupleHashKey, TimeStamp>>();
+    RefPtr<nsIRunnable> cleanupFn = NS_NewRunnableFunction(__func__, [&] {
+      if (AppShutdown::IsInOrBeyond(ShutdownPhase::XPCOMWillShutdown)) {
+        auto lock = sTimerIdToStarts.Lock();
+        *lock = nullptr;  // deletes, see UniquePtr.h
+        return;
+      }
+      RunOnShutdown(
+          [&] {
+            auto lock = sTimerIdToStarts.Lock();
+            *lock = nullptr;  // deletes, see UniquePtr.h
+          },
+          ShutdownPhase::XPCOMWillShutdown);
+    });
+    // Both getting the main thread and dispatching to it can fail.
+    // In that event we leak. Grab a pointer so we have something to NS_RELEASE
+    // in that case.
+    nsIRunnable* temp = cleanupFn.get();
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread))) ||
+        NS_FAILED(mainThread->Dispatch(cleanupFn.forget(),
+                                       nsIThread::DISPATCH_NORMAL))) {
+      // Failed to dispatch cleanup routine.
+      // First, un-leak the runnable (but only if we actually attempted
+      // dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
+      // Next, cleanup immediately, and allow metrics to try again later.
+      *lock = nullptr;
+      return Nothing();
+    }
+  }
+  return Some(std::move(lock));
+}
+
+}  // namespace mozilla::glean
+
+// Called from within FOG's Rust impl.
+extern "C" NS_EXPORT void GIFFT_TimingDistributionStart(
+    uint32_t aMetricId, mozilla::glean::TimerId aTimerId) {
+  auto mirrorId = mozilla::glean::HistogramIdForMetric(aMetricId);
+  if (mirrorId) {
+    mozilla::glean::GetTimerIdToStartsLock().apply([&](auto& lock) {
+      auto tuple = std::make_tuple(aMetricId, aTimerId);
+      // It should be all but impossible for anyone to have already inserted
+      // this timer for this metric given the monotonicity of timer ids.
+      (void)NS_WARN_IF(lock.ref()->Remove(tuple));
+      lock.ref()->InsertOrUpdate(tuple, mozilla::TimeStamp::Now());
+    });
+  }
+}
+
+// Called from within FOG's Rust impl.
+extern "C" NS_EXPORT void GIFFT_TimingDistributionStopAndAccumulate(
+    uint32_t aMetricId, mozilla::glean::TimerId aTimerId) {
+  auto mirrorId = mozilla::glean::HistogramIdForMetric(aMetricId);
+  if (mirrorId) {
+    mozilla::glean::GetTimerIdToStartsLock().apply([&](auto& lock) {
+      auto optStart = lock.ref()->Extract(std::make_tuple(aMetricId, aTimerId));
+      // The timer might not be in the map to be removed if it's already been
+      // cancelled or stop_and_accumulate'd.
+      if (!NS_WARN_IF(!optStart)) {
+        AccumulateTimeDelta(mirrorId.extract(), optStart.extract());
+      }
+    });
+  }
+}
+
+// Called from within FOG's Rust impl.
+extern "C" NS_EXPORT void GIFFT_TimingDistributionAccumulateRawMillis(
+    uint32_t aMetricId, uint32_t aMS) {
+  auto mirrorId = mozilla::glean::HistogramIdForMetric(aMetricId);
+  if (mirrorId) {
+    Accumulate(mirrorId.extract(), aMS);
+  }
+}
+
+// Called from within FOG's Rust impl.
+extern "C" NS_EXPORT void GIFFT_TimingDistributionCancel(
+    uint32_t aMetricId, mozilla::glean::TimerId aTimerId) {
+  auto mirrorId = mozilla::glean::HistogramIdForMetric(aMetricId);
+  if (mirrorId) {
+    mozilla::glean::GetTimerIdToStartsLock().apply([&](auto& lock) {
+      // The timer might not be in the map to be removed if it's already been
+      // cancelled or stop_and_accumulate'd.
+      (void)NS_WARN_IF(
+          !lock.ref()->Remove(std::make_tuple(aMetricId, aTimerId)));
+    });
+  }
+}
+
+namespace mozilla::glean {
+
+namespace impl {
+
+TimerId TimingDistributionMetric::Start() const {
+  return fog_timing_distribution_start(mId);
+}
+
+void TimingDistributionMetric::StopAndAccumulate(const TimerId&& aId) const {
+  fog_timing_distribution_stop_and_accumulate(mId, aId);
+}
+
+// Intentionally not exposed to JS for lack of use case and a time duration
+// type.
+void TimingDistributionMetric::AccumulateRawDuration(
+    const TimeDuration& aDuration) const {
+  fog_timing_distribution_accumulate_raw_nanos(
+      mId, uint64_t(aDuration.ToMicroseconds() * 1000.00));
+}
+
+void TimingDistributionMetric::Cancel(const TimerId&& aId) const {
+  fog_timing_distribution_cancel(mId, aId);
+}
+
+Result<Maybe<DistributionData>, nsCString>
+TimingDistributionMetric::TestGetValue(const nsACString& aPingName) const {
+  nsCString err;
+  if (fog_timing_distribution_test_get_error(mId, &err)) {
+    return Err(err);
+  }
+  if (!fog_timing_distribution_test_has_value(mId, &aPingName)) {
+    return Maybe<DistributionData>();
+  }
+  nsTArray<uint64_t> buckets;
+  nsTArray<uint64_t> counts;
+  uint64_t sum;
+  fog_timing_distribution_test_get_value(mId, &aPingName, &sum, &buckets,
+                                         &counts);
+  return Some(DistributionData(buckets, counts, sum));
+}
+
+}  // namespace impl
+
+/* virtual */
+JSObject* GleanTimingDistribution::WrapObject(
+    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
+  return dom::GleanTimingDistribution_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+uint64_t GleanTimingDistribution::Start() { return mTimingDist.Start(); }
+
+void GleanTimingDistribution::StopAndAccumulate(uint64_t aId) {
+  mTimingDist.StopAndAccumulate(std::move(aId));
+}
+
+void GleanTimingDistribution::Cancel(uint64_t aId) {
+  mTimingDist.Cancel(std::move(aId));
+}
+
+void GleanTimingDistribution::TestGetValue(
+    const nsACString& aPingName,
+    dom::Nullable<dom::GleanDistributionData>& aRetval, ErrorResult& aRv) {
+  auto result = mTimingDist.TestGetValue(aPingName);
+  if (result.isErr()) {
+    aRv.ThrowDataError(result.unwrapErr());
+    return;
+  }
+  auto optresult = result.unwrap();
+  if (optresult.isNothing()) {
+    return;
+  }
+
+  dom::GleanDistributionData ret;
+  ret.mSum = optresult.ref().sum;
+  auto& data = optresult.ref().values;
+  for (const auto& entry : data) {
+    dom::binding_detail::RecordEntry<nsCString, uint64_t> bucket;
+    bucket.mKey = nsPrintfCString("%" PRIu64, entry.GetKey());
+    bucket.mValue = entry.GetData();
+    ret.mValues.Entries().EmplaceBack(std::move(bucket));
+  }
+  aRetval.SetValue(std::move(ret));
+}
+
+void GleanTimingDistribution::TestAccumulateRawMillis(uint64_t aSample) {
+  mTimingDist.AccumulateRawDuration(TimeDuration::FromMilliseconds(aSample));
+}
+
+}  // namespace mozilla::glean