fix a lot of low level cppcheck warnings (#9623)

* simplify the observer pattern, since all the called functions are const getters.
* use arduino macro over std: for numerical values and refactor local variables in drawScrollbar()
* oh, so Cppcheck actually complained about const pointers not being const.
* slowly getting out of ifdef hell
* fix inkHUD warnings as well
* last 2 check warnings
* git checks should fail on low defects from now on

src/modules/CannedMessageModule.cpp

@@ -1209,14 +1209,13 @@ int32_t CannedMessageModule::runOnce()
                 this->cursor = 0;
 
                 // Tell Screen to jump straight to the TextMessage frame
-                UIFrameEvent e;
                 e.action = UIFrameEvent::Action::SWITCH_TO_TEXTMESSAGE;
                 this->notifyObservers(&e);
 
                 // Now deactivate this module
                 this->runState = CANNED_MESSAGE_RUN_STATE_INACTIVE;
 
-                return INT32_MAX; // don’t fall back into canned list
+                return INT32_MAX; // don't fall back into canned list
             } else {
                 this->runState = CANNED_MESSAGE_RUN_STATE_INACTIVE;
             }
@@ -1237,14 +1236,13 @@ int32_t CannedMessageModule::runOnce()
                     this->cursor = 0;
 
                     // Tell Screen to jump straight to the TextMessage frame
-                    UIFrameEvent e;
                     e.action = UIFrameEvent::Action::SWITCH_TO_TEXTMESSAGE;
                     this->notifyObservers(&e);
 
                     // Now deactivate this module
                     this->runState = CANNED_MESSAGE_RUN_STATE_INACTIVE;
 
-                    return INT32_MAX; // don’t fall back into canned list
+                    return INT32_MAX; // don't fall back into canned list
                 }
             } else {
                 this->runState = CANNED_MESSAGE_RUN_STATE_INACTIVE;
@@ -1255,11 +1253,10 @@ int32_t CannedMessageModule::runOnce()
         this->freetext = "";
         this->cursor = 0;
 
-        UIFrameEvent e;
         e.action = UIFrameEvent::Action::REGENERATE_FRAMESET;
         this->notifyObservers(&e);
 
-        // Immediately stop, don’t linger on canned screen
+        // Immediately stop, don't linger on canned screen
         return INT32_MAX;
     }
     // Highlight [Select Destination] initially when entering the message list
@@ -2070,7 +2067,7 @@ void CannedMessageModule::drawFrame(OLEDDisplay *display, OLEDDisplayUiState *st
             // Draw lines with emotes
             int rowHeight = FONT_HEIGHT_SMALL;
             int yLine = inputY;
-            for (auto &line : lines) {
+            for (const auto &line : lines) {
                 int nextX = x;
                 for (const auto &token : line) {
                     if (token.first) {

src/modules/ExternalNotificationModule.cpp

@@ -367,7 +367,7 @@ ProcessMessage ExternalNotificationModule::handleReceived(const meshtastic_MeshP
                 }
             }
 
-            meshtastic_NodeInfoLite *sender = nodeDB->getMeshNode(mp.from);
+            const meshtastic_NodeInfoLite *sender = nodeDB->getMeshNode(mp.from);
             meshtastic_Channel ch = channels.getByIndex(mp.channel ? mp.channel : channels.getPrimaryIndex());
 
             // If we receive a broadcast message, apply channel mute setting

src/modules/StatusLEDModule.cpp

@@ -23,7 +23,6 @@ int StatusLEDModule::handleStatusUpdate(const meshtastic::Status *arg)
 {
     switch (arg->getStatusType()) {
     case STATUS_TYPE_POWER: {
-        meshtastic::PowerStatus *powerStatus = (meshtastic::PowerStatus *)arg;
         if (powerStatus->getHasUSB() || powerStatus->getIsCharging()) {
             power_state = charging;
             if (powerStatus->getBatteryChargePercent() >= 100) {
@@ -39,7 +38,6 @@ int StatusLEDModule::handleStatusUpdate(const meshtastic::Status *arg)
         break;
     }
     case STATUS_TYPE_BLUETOOTH: {
-        meshtastic::BluetoothStatus *bluetoothStatus = (meshtastic::BluetoothStatus *)arg;
         switch (bluetoothStatus->getConnectionState()) {
         case meshtastic::BluetoothStatus::ConnectionState::DISCONNECTED: {
             ble_state = unpaired;
@@ -199,33 +197,30 @@ void StatusLEDModule::setPowerLED(bool LEDon)
         PMU->setChargingLedMode(LEDon ? XPOWERS_CHG_LED_ON : XPOWERS_CHG_LED_OFF);
     }
 #endif
-    if (LEDon)
-        LEDon = LED_STATE_ON;
-    else
-        LEDon = LED_STATE_OFF;
+    uint8_t ledState = LEDon ? LED_STATE_ON : LED_STATE_OFF;
 #ifdef PCA_LED_POWER
-    io.digitalWrite(PCA_LED_POWER, LEDon);
+    io.digitalWrite(PCA_LED_POWER, ledState);
 #endif
 #ifdef PCA_LED_ENABLE
-    io.digitalWrite(PCA_LED_ENABLE, LEDon);
+    io.digitalWrite(PCA_LED_ENABLE, ledState);
 #endif
 #ifdef LED_POWER
-    digitalWrite(LED_POWER, LEDon);
+    digitalWrite(LED_POWER, ledState);
 #endif
 #ifdef LED_PAIRING
-    digitalWrite(LED_PAIRING, LEDon);
+    digitalWrite(LED_PAIRING, ledState);
 #endif
 
 #ifdef Battery_LED_1
-    digitalWrite(Battery_LED_1, LEDon);
+    digitalWrite(Battery_LED_1, ledState);
 #endif
 #ifdef Battery_LED_2
-    digitalWrite(Battery_LED_2, LEDon);
+    digitalWrite(Battery_LED_2, ledState);
 #endif
 #ifdef Battery_LED_3
-    digitalWrite(Battery_LED_3, LEDon);
+    digitalWrite(Battery_LED_3, ledState);
 #endif
 #ifdef Battery_LED_4
-    digitalWrite(Battery_LED_4, LEDon);
+    digitalWrite(Battery_LED_4, ledState);
 #endif
 }

src/modules/StoreForwardModule.cpp

@@ -131,9 +131,7 @@ void StoreForwardModule::historySend(uint32_t secAgo, uint32_t to)
 uint32_t StoreForwardModule::getNumAvailablePackets(NodeNum dest, uint32_t last_time)
 {
     uint32_t count = 0;
-    if (lastRequest.find(dest) == lastRequest.end()) {
-        lastRequest.emplace(dest, 0);
-    }
+    lastRequest.emplace(dest, 0);
     for (uint32_t i = lastRequest[dest]; i < this->packetHistoryTotalCount; i++) {
         if (this->packetHistory[i].time && (this->packetHistory[i].time > last_time)) {
             // Client is only interested in packets not from itself and only in broadcast packets or packets towards it.

src/modules/Telemetry/Sensor/AddI2CSensorTemplate.h

@@ -8,7 +8,7 @@
 
 static std::forward_list<TelemetrySensor *> sensors;
 
-template <typename T> void addSensor(ScanI2C *i2cScanner, ScanI2C::DeviceType type)
+template <typename T> void addSensor(const ScanI2C *i2cScanner, ScanI2C::DeviceType type)
 {
     ScanI2C::FoundDevice dev = i2cScanner->find(type);
     if (dev.type != ScanI2C::DeviceType::NONE || type == ScanI2C::DeviceType::NONE) {

src/modules/Telemetry/Sensor/PMSA003ISensor.cpp

@@ -86,7 +86,7 @@ bool PMSA003ISensor::getMetrics(meshtastic_Telemetry *measurement)
         return false;
     }
 
-    auto read16 = [](uint8_t *data, uint8_t idx) -> uint16_t { return (data[idx] << 8) | data[idx + 1]; };
+    auto read16 = [](const uint8_t *data, uint8_t idx) -> uint16_t { return (data[idx] << 8) | data[idx + 1]; };
 
     computedChecksum = 0;
 

src/modules/Telemetry/Sensor/SCD4XSensor.cpp

@@ -111,7 +111,7 @@ bool SCD4XSensor::getMetrics(meshtastic_Telemetry *measurement)
 
     bool dataReady;
     error = scd4x.getDataReadyStatus(dataReady);
-    if (!dataReady) {
+    if (error != SCD4X_NO_ERROR || !dataReady) {
 #if defined(SCD4X_I2C_CLOCK_SPEED) && defined(CAN_RECLOCK_I2C)
         reClockI2C(currentClock, _bus, false);
 #endif
@@ -419,7 +419,7 @@ bool SCD4XSensor::setTemperature(float tempReference)
     LOG_INFO("%s: Setting reference temperature at: %.2f", sensorName, tempReference);
 
     error = scd4x.getDataReadyStatus(dataReady);
-    if (!dataReady) {
+    if (error != SCD4X_NO_ERROR || !dataReady) {
         LOG_ERROR("%s: Data is not ready", sensorName);
         return false;
     }

src/modules/Telemetry/Sensor/SEN5XSensor.cpp

@@ -182,7 +182,7 @@ uint8_t SEN5XSensor::readBuffer(uint8_t *buffer, uint8_t byteNumber)
     return receivedBytes;
 }
 
-uint8_t SEN5XSensor::sen5xCRC(uint8_t *buffer)
+uint8_t SEN5XSensor::sen5xCRC(const uint8_t *buffer)
 {
     // This code is based on Sensirion's own implementation
     // https://github.com/Sensirion/arduino-core/blob/41fd02cacf307ec4945955c58ae495e56809b96c/src/SensirionCrc.cpp

src/modules/Telemetry/Sensor/SEN5XSensor.h

@@ -114,7 +114,7 @@ See: https://sensirion.com/resource/application_note/low_power_mode/sen5x
     bool sendCommand(uint16_t command);
     bool sendCommand(uint16_t command, uint8_t *buffer, uint8_t byteNumber = 0);
     uint8_t readBuffer(uint8_t *buffer, uint8_t byteNumber); // Return number of bytes received
-    uint8_t sen5xCRC(uint8_t *buffer);
+    uint8_t sen5xCRC(const uint8_t *buffer);
     bool startCleaning();
     uint8_t getMeasurements();
     // bool readRawValues();

src/modules/TraceRouteModule.cpp

@@ -266,7 +266,7 @@ void TraceRouteModule::alterReceivedProtobuf(meshtastic_MeshPacket &p, meshtasti
     }
 }
 
-void TraceRouteModule::updateNextHops(meshtastic_MeshPacket &p, meshtastic_RouteDiscovery *r)
+void TraceRouteModule::updateNextHops(const meshtastic_MeshPacket &p, meshtastic_RouteDiscovery *r)
 {
     // E.g. if the route is A->B->C->D and we are B, we can set C as next-hop for C and D
     // Similarly, if we are C, we can set D as next-hop for D

src/modules/TraceRouteModule.h

@@ -62,7 +62,7 @@ class TraceRouteModule : public ProtobufModule<meshtastic_RouteDiscovery>,
     void appendMyIDandSNR(meshtastic_RouteDiscovery *r, float snr, bool isTowardsDestination, bool SNRonly);
 
     // Update next-hops in the routing table based on the returned route
-    void updateNextHops(meshtastic_MeshPacket &p, meshtastic_RouteDiscovery *r);
+    void updateNextHops(const meshtastic_MeshPacket &p, meshtastic_RouteDiscovery *r);
 
     // Helper to update next-hop for a single node
     void maybeSetNextHop(NodeNum target, uint8_t nextHopByte);