Memory Optimization: Add function to List class to pre-allocate a giv…

…en size

NodeManagerLibrary.h

@@ -169,14 +169,12 @@ template<typename T> class List {
     _internalArray = NULL;
     _endPosition = 0;
     _allocBlocks = 0;
-    _preAllocBlocks = 0;
   }
   ~List() {
     delete[] _internalArray;
     _internalArray = NULL;
     _endPosition = 0;
     _allocBlocks = 0;
-    _preAllocBlocks = 0;
   }
   void push(T item) {
     if (_endPosition == _allocBlocks) _AllocOneBlock(false);
@@ -186,7 +184,7 @@ template<typename T> class List {
   void pop() {
     if (_endPosition == 0) return;
     --_endPosition;
-    if (_allocBlocks > _preAllocBlocks) _DeAllocOneBlock(false);
+    _DeAllocOneBlock(false);
   }
   T get(int position) {
     position = position -1;
@@ -197,11 +195,18 @@ template<typename T> class List {
   inline iterator end() { return _internalArray + _endPosition; }
   inline bool empty() { return (_endPosition == 0); }
   inline unsigned int size() { return _endPosition; }
+  void allocateBlocks(int alloc) {
+    _allocBlocks = alloc;
+    T* newArray = new T[_allocBlocks];
+    for (int i = 0; i < _endPosition; ++i) newArray[i] = _internalArray[i];
+    delete[] _internalArray;
+    _internalArray = newArray;
+  }
+
 private:
   T* _internalArray;
   int _endPosition;
   int _allocBlocks;
-  int _preAllocBlocks;
   void _AllocOneBlock(bool shiftItems) {
     ++_allocBlocks;
     T* newArray = new T[_allocBlocks];
@@ -1367,7 +1372,7 @@ class SensorVL53L0X: public Sensor {
 */
 class NodeManager {
   public:
-    NodeManager();
+    NodeManager(int sensorcount = 0);
     // [10] send the same message multiple times (default: 1)
     void setRetries(int value);
     int getRetries();

NodeManagerLibrary.ino

@@ -2995,6 +2995,8 @@ SensorPlantowerPMS::SensorPlantowerPMS(NodeManager& node_manager, int rxpin, int
 
 // what to do during before
 void SensorPlantowerPMS::onBefore() {
+  // Allocate memory for all children at once (to prevent memory fragmentation)
+  children.allocateBlocks(3);
   // register the child
   new ChildInt(this, _node->getAvailableChildId(), S_DUST, V_LEVEL, "PM1.0");
   new ChildInt(this, _node->getAvailableChildId(), S_DUST, V_LEVEL, "PM2.5");
@@ -3425,9 +3427,12 @@ void SensorConfiguration::onReceive(MyMessage* message) {
 */
 
 // initialize the node manager
-NodeManager::NodeManager() {
+NodeManager::NodeManager(int sensorcount) {
   // setup the message container
   _message = MyMessage();
+  if (sensorcount>0) {
+    sensors.allocateBlocks(sensorcount);
+  }
 }
 
 int NodeManager::_last_interrupt_pin = -1;