[feat] add statistics module

src/common/sequence_number_unwrapper.h

@@ -0,0 +1,70 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2024-08-21
+ * Copyright (c) 2024 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _SEQUENCE_NUMBER_UNWRAPPER_H_
+#define _SEQUENCE_NUMBER_UNWRAPPER_H_
+
+#include <stdint.h>
+
+#include <limits>
+#include <type_traits>
+
+// A sequence number unwrapper where the first unwrapped value equals the
+// first value being unwrapped.
+template <typename T, T M = 0>
+class SeqNumUnwrapper {
+  static_assert(
+      std::is_unsigned<T>::value &&
+          std::numeric_limits<T>::max() < std::numeric_limits<int64_t>::max(),
+      "Type unwrapped must be an unsigned integer smaller than int64_t.");
+
+ public:
+  // Unwraps `value` and updates the internal state of the unwrapper.
+  int64_t Unwrap(T value) {
+    if (!last_value_) {
+      last_unwrapped_ = {value};
+    } else {
+      last_unwrapped_ += Delta(*last_value_, value);
+    }
+
+    last_value_ = value;
+    return last_unwrapped_;
+  }
+
+  // Returns the `value` without updating the internal state of the unwrapper.
+  int64_t PeekUnwrap(T value) const {
+    if (!last_value_) {
+      return value;
+    }
+    return last_unwrapped_ + Delta(*last_value_, value);
+  }
+
+  // Resets the unwrapper to its initial state. Unwrapped sequence numbers will
+  // being at 0 after resetting.
+  void Reset() {
+    last_unwrapped_ = 0;
+    last_value_.reset();
+  }
+
+ private:
+  static int64_t Delta(T last_value, T new_value) {
+    constexpr int64_t kBackwardAdjustment =
+        M == 0 ? int64_t{std::numeric_limits<T>::max()} + 1 : M;
+    int64_t result = ForwardDiff<T, M>(last_value, new_value);
+    if (!AheadOrAt<T, M>(new_value, last_value)) {
+      result -= kBackwardAdjustment;
+    }
+    return result;
+  }
+
+  int64_t last_unwrapped_ = 0;
+  std::unique_ptr<T> last_value_;
+};
+
+using RtpTimestampUnwrapper = SeqNumUnwrapper<uint32_t>;
+using RtpSeqNumUnwrapper = SeqNumUnwrapper<uint16_t>;
+
+#endif

src/statistics/receiver_statistics.cpp

@@ -0,0 +1,7 @@
+#include "receiver_statistics.h"
+
+#include "log.h"
+
+ReceiverStatistics::ReceiverStatistics() {}
+
+ReceiverStatistics::~ReceiverStatistics() {}

src/statistics/receiver_statistics.h

@@ -0,0 +1,21 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2024-09-04
+ * Copyright (c) 2024 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _RECEIVER_STATISTICS_H_
+#define _RECEIVER_STATISTICS_H_
+
+#include "statistics_base.h"
+
+class ReceiverStatistics : public StatisticsBase {
+ public:
+  ReceiverStatistics();
+  virtual ~ReceiverStatistics();
+
+ private:
+  /* data */
+};
+
+#endif

src/statistics/sender_statistics.cpp

@@ -0,0 +1,7 @@
+#include "sender_statistics.h"
+
+#include "log.h"
+
+SenderStatistics::SenderStatistics() {}
+
+SenderStatistics::~SenderStatistics() {}

src/statistics/sender_statistics.h

@@ -0,0 +1,21 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2024-09-04
+ * Copyright (c) 2024 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _SENDER_STATISTICS_H_
+#define _SENDER_STATISTICS_H_
+
+#include "statistics_base.h"
+
+class SenderStatistics : public StatisticsBase {
+ public:
+  SenderStatistics();
+  virtual ~SenderStatistics();
+
+ private:
+  /* data */
+};
+
+#endif

src/statistics/statistics_base.cpp

@@ -0,0 +1,5 @@
+#include "statistics_base.h"
+
+StatisticsBase::StatisticsBase() {}
+
+StatisticsBase::~StatisticsBase() {}

src/statistics/statistics_base.h

@@ -0,0 +1,19 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2024-09-04
+ * Copyright (c) 2024 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _STATISTICS_BASE_H_
+#define _STATISTICS_BASE_H_
+
+class StatisticsBase {
+ public:
+  StatisticsBase();
+  virtual ~StatisticsBase();
+
+ private:
+  /* data */
+};
+
+#endif

src/transmission/ice_transmission.h

@@ -11,6 +11,7 @@
 
 #include "congestion_control.h"
 #include "ice_agent.h"
+#include "receiver_statistics.h"
 #include "ringbuffer.h"
 #include "rtp_audio_receiver.h"
 #include "rtp_audio_sender.h"
@@ -20,6 +21,7 @@
 #include "rtp_packet.h"
 #include "rtp_video_receiver.h"
 #include "rtp_video_sender.h"
+#include "sender_statistics.h"
 #include "ws_transmission.h"
 
 class IceTransmission {
@@ -150,6 +152,10 @@ class IceTransmission {
   bool start_send_packet_ = false;
 
   uint32_t last_complete_frame_ts_ = 0;
+
+ private:
+  std::unique_ptr<SenderStatistics> sender_statistics_ = nullptr;
+  std::unique_ptr<ReceiverStatistics> receiver_statistics_ = nullptr;
 };
 
 #endif

xmake.lua

@@ -170,9 +170,15 @@ target("qos")
     add_files("src/qos/kcp/*.c")
     add_includedirs("src/qos/kcp", {public = true})
 
+target("statistics")
+    set_kind("object")
+    add_deps("log")
+    add_files("src/statistics/*.cpp")
+    add_includedirs("src/statistics", {public = true})
+
 target("transmission")
     set_kind("object")
-    add_deps("log", "ws", "ice", "qos", "rtp", "rtcp")
+    add_deps("log", "ws", "ice", "qos", "rtp", "rtcp", "statistics")
     add_files("src/transmission/*.cpp")
     add_includedirs("src/ws", "src/ice", "src/qos", {public = true})