Report metrics about negotiated ciphers.

talk/app/webrtc/fakemetricsobserver.h

+/*
+ * libjingle
+ * Copyright 2015 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef TALK_APP_WEBRTC_FAKEMETRICSOBSERVER_H_
+#define TALK_APP_WEBRTC_FAKEMETRICSOBSERVER_H_
+
+#include <map>
+#include <string>
+
+#include "talk/app/webrtc/peerconnectioninterface.h"
+
+namespace webrtc {
+
+class FakeMetricsObserver : public MetricsObserverInterface {
+ public:
+  FakeMetricsObserver() { Reset(); }
+  void Reset() {

[tommi (sloooow) - chröme, 2015/07/02 11:32:29]

Is this method necessary? (can we just do this in the ctor and not expose a
method?)

[joachim, 2015/07/02 22:06:06]

Reset is used by the unittests, so this needs to stay.

+    memset(counters_, 0, sizeof(counters_));
+    memset(int_histogram_samples_, 0, sizeof(int_histogram_samples_));
+    for (std::string& type : string_histogram_samples_) {
+      type.clear();
+    }
+  }
+
+  void IncrementCounter(PeerConnectionMetricsCounter type) override {
+    counters_[type]++;

[tommi (sloooow) - chröme, 2015/07/02 11:32:29]

nit: ++counters_[type];

It looks like this class is single thread.  Can you add a ThreadChecker to the
class and DCHECKs to ensure all methods are called on the right thread?

Also, it would be good to split the implementation out into a separate .cc file.

[joachim, 2015/07/02 22:06:06]

Done.
Done.
Done.

+  }
+  void AddHistogramSample(PeerConnectionMetricsName type,
+                          int value) override {
+    ASSERT(int_histogram_samples_[type] == 0);

[tommi (sloooow) - chröme, 2015/07/02 11:32:29]

can we use DCHECK instead of ASSERT (see checks.h)

[joachim, 2015/07/02 22:06:05]

Done.

+    int_histogram_samples_[type] = value;
+  }
+  void AddHistogramSample(PeerConnectionMetricsName type,
+                          const std::string& value) override {
+    string_histogram_samples_[type].assign(value);
+  }
+
+  // Accessors to be used by the tests.
+  int GetCounter(PeerConnectionMetricsCounter type) const {
+    return counters_[type];
+  }
+  int GetIntHistogramSample(PeerConnectionMetricsName type) const {
+    return int_histogram_samples_[type];
+  }
+  const std::string& GetStringHistogramSample(
+      PeerConnectionMetricsName type) const {
+    return string_histogram_samples_[type];
+  }
+
+  int AddRef() override { return 1; }

[tommi (sloooow) - chröme, 2015/07/02 11:32:29]

why not implement proper reference counting?  See e.g. RefCountedObject.

[joachim, 2015/07/02 22:06:05]

I assume it was done like this because the class was only used for testing.
Anyway, changed it.

+  int Release() override { return 1; }
+
+ private:
+  int counters_[kPeerConnectionMetricsCounter_Max];
+  int int_histogram_samples_[kPeerConnectionMetricsCounter_Max];
+  std::string string_histogram_samples_[kPeerConnectionMetricsName_Max];
+};
+
+}  // namespace webrtc
+
+#endif  // TALK_APP_WEBRTC_FAKEMETRICSOBSERVER_H_