Implement peak bandwidth statistics

Closes #4

Author: davidpolverari

src/cbm.cpp

@@ -180,7 +180,7 @@ int main(int argc, char **argv) {
 
             // Create the interface table
             VerticalTable interfaceTable(screen);
-            interfaceTable.setColumns(4);
+            interfaceTable.setColumns(6);
             interfaceTable.setActiveStyle(A_BOLD);
             interfaceTable.setActiveRow(1);
             // Position the interface table
@@ -272,6 +272,14 @@ int main(int argc, char **argv) {
                 interfaceTable.setStyle(3, 0,
                                         COLOR_PAIR(COLOR_HEADING) | A_BOLD);
 
+                interfaceTable.setText (4, 0, "Receive Max");
+                interfaceTable.setStyle(4, 0,
+                                        COLOR_PAIR(COLOR_HEADING) | A_BOLD);
+
+                interfaceTable.setText (5, 0, "Transmit Max");
+                interfaceTable.setStyle(5, 0,
+                                        COLOR_PAIR(COLOR_HEADING) | A_BOLD);
+
                 unsigned index = 1;
                 for (statistics::Reader::Interfaces::const_iterator
                         interface = statisticsReader.getInterfaces().begin();
@@ -296,6 +304,14 @@ int main(int argc, char **argv) {
                                                             + interface->getTransmitSpeed(), bit_mode));
                     interfaceTable.setStyle(3, index, A_NORMAL);
 
+                    interfaceTable.setText(4, index,
+                                            formatBandwidth(interface->getReceiveMax(), bit_mode));
+                    interfaceTable.setStyle(4, index, A_NORMAL);
+
+                    interfaceTable.setText(5, index,
+                                            formatBandwidth(interface->getTransmitMax(), bit_mode));
+                    interfaceTable.setStyle(5, index, A_NORMAL);
+
                     if (index == interfaceTable.getActiveRow()) {
                         // Get the details for the active interface
                         struct ifreq req;

src/statistics.cpp

@@ -34,7 +34,7 @@
 
 namespace statistics {
 
-Interface::Interface(const std::string& name) : name_(name), updated_(false) {}
+Interface::Interface(const std::string& name) : name_(name), updated_(false), receiveMax_(0.0), transmitMax_(0.0) {}
 
 class InterfaceNameMatchesPredicate {
 public:
@@ -55,6 +55,8 @@ class InterfaceNotUpdatedPredicate {
 };
 
 void Interface::update(const Statistics& statistics) {
+    static unsigned int count = 0;
+
     memcpy(statistics_ + 1, statistics_ + 0, sizeof(Statistics));
     memcpy(statistics_, &statistics, sizeof(Statistics));
 
@@ -68,6 +70,18 @@ void Interface::update(const Statistics& statistics) {
     receiveSpeed_ = (x1.rx_bytes - x0.rx_bytes) / timeDelta;
     transmitSpeed_ = (x1.tx_bytes - x0.tx_bytes) / timeDelta;
 
+    count++;
+
+    // Waits some iterations before calculating max speeds.
+    // This avoids presenting wrong initial peaks.
+    if (count < 8)
+        return;
+
+    if (receiveSpeed_ > receiveMax_)
+        receiveMax_ = receiveSpeed_;
+    if (transmitSpeed_ > transmitMax_)
+        transmitMax_ = transmitSpeed_;
+
     updated_ = true;
 }
 
@@ -168,6 +182,14 @@ double Interface::getTransmitSpeed() const {
     return transmitSpeed_;
 }
 
+double Interface::getReceiveMax() const {
+    return receiveMax_;
+}
+
+double Interface::getTransmitMax() const {
+    return transmitMax_;
+}
+
 const Reader::Interfaces& Reader::getInterfaces() const {
     return interfaces_;
 }

src/statistics.hpp

@@ -49,12 +49,15 @@ class Interface {
 
     double getReceiveSpeed() const;
     double getTransmitSpeed() const;
+    double getReceiveMax() const;
+    double getTransmitMax() const;
 
 private:
     std::string name_;
     bool updated_;
     Statistics statistics_[2];
     double receiveSpeed_, transmitSpeed_;
+    double receiveMax_, transmitMax_;
 };
 
 class Reader {