make onSent optional and remove underscores for virtual functions

Author: P-R-O-C-H-Y

Diff for: docs/en/api/espnow.rst

@@ -231,27 +231,27 @@ Set the local master key (LMK) for the peer.
 
 * ``lmk``: Local master key.
 
-_onReceive
+onReceive
 ^^^^^^^^^^
 
 Callback function to handle incoming data from the peer. This is a pure virtual method that must be implemented by the upper class.
 
 .. code-block:: cpp
 
-    void _onReceive(const uint8_t *data, int len, bool broadcast);
+    void onReceive(const uint8_t *data, int len, bool broadcast);
 
 * ``data``: Pointer to the received data.
 * ``len``: Length of the received data.
 * ``broadcast``: ``true`` if the data is broadcasted, ``false`` otherwise.
 
-_onSent
+onSent
 ^^^^^^^
 
-Callback function to handle the completion of sending data to the peer. This is a pure virtual method that must be implemented by the upper class.
+Optional callback function to handle the completion of sending data to the peer. This is a pure virtual method that must be implemented by the upper class.
 
 .. code-block:: cpp
 
-    void _onSent(bool success);
+    void onSent(bool success);
 
 * ``success``: ``true`` if the data is sent successfully, ``false`` otherwise.
 

Diff for: libraries/ESP_NOW/examples/ESP_NOW_Broadcast_Master/ESP_NOW_Broadcast_Master.ino

@@ -53,16 +53,11 @@ public:
         return true;
     }
 
-    void _onReceive(const uint8_t *data, size_t len, bool broadcast) {
+    void onReceive(const uint8_t *data, size_t len, bool broadcast) {
         // The broadcast peer will never receive any data. Rather, it will only send data.
         // Data broadcasted will be received by the actual object of the peer that made the broadcast.
         // It is still required to be implemented because it is a pure virtual method.
     }
-
-    void _onSent(bool success) {
-        // As broadcast messages does not require any acknowledgment, this method will never be called.
-        // It is still required to be implemented because it is a pure virtual method.
-    }
 };
 
 /* Global Variables */

Diff for: libraries/ESP_NOW/examples/ESP_NOW_Network/ESP_NOW_Network.ino

@@ -133,7 +133,7 @@ public:
         return send(data, len);
     }
 
-    void _onReceive(const uint8_t *data, size_t len, bool broadcast) {
+    void onReceive(const uint8_t *data, size_t len, bool broadcast) {
         esp_now_data_t *msg = (esp_now_data_t *)data;
 
         if (peer_ready == false && msg->ready == true) {
@@ -159,7 +159,7 @@ public:
         }
     }
 
-    void _onSent(bool success) {
+    void onSent(bool success) {
         bool broadcast = memcmp(addr(), ESP_NOW.BROADCAST_ADDR, ESP_NOW_ETH_ALEN) == 0;
         if (broadcast) {
             log_v("Broadcast message reported as sent %s", success ? "successfully" : "unsuccessfully");

Diff for: libraries/ESP_NOW/src/ESP32_NOW.cpp

@@ -118,8 +118,8 @@ static void _esp_now_rx_cb(const esp_now_recv_info_t *info, const uint8_t *data,
             log_v("Checking peer " MACSTR, MAC2STR(_esp_now_peers[i]->addr()));
         }
         if(_esp_now_peers[i] != NULL && memcmp(info->src_addr, _esp_now_peers[i]->addr(), ESP_NOW_ETH_ALEN) == 0){
-            log_v("Calling _onReceive");
-            _esp_now_peers[i]->_onReceive(data, len, broadcast);
+            log_v("Calling onReceive");
+            _esp_now_peers[i]->onReceive(data, len, broadcast);
             return;
         }
     }
@@ -130,7 +130,7 @@ static void _esp_now_tx_cb(const uint8_t *mac_addr, esp_now_send_status_t status
     //find the peer and call it's callback
     for(uint8_t i=0; i<ESP_NOW_MAX_TOTAL_PEER_NUM; i++){
         if(_esp_now_peers[i] != NULL && memcmp(mac_addr, _esp_now_peers[i]->addr(), ESP_NOW_ETH_ALEN) == 0){
-            _esp_now_peers[i]->_onSent(status == ESP_NOW_SEND_SUCCESS);
+            _esp_now_peers[i]->onSent(status == ESP_NOW_SEND_SUCCESS);
             return;
         }
     }

Diff for: libraries/ESP_NOW/src/ESP32_NOW.h

@@ -3,6 +3,7 @@
 #include "esp_wifi_types.h"
 #include "Print.h"
 #include "esp_now.h"
+#include "esp32-hal-log.h"
 
 class ESP_NOW_Peer {
 private:
@@ -37,8 +38,10 @@ class ESP_NOW_Peer {
   operator bool() const;
 
   //must be implemented by the upper class
-  virtual void _onReceive(const uint8_t * data, size_t len, bool broadcast) = 0;
-  virtual void _onSent(bool success) = 0;
+  virtual void onReceive(const uint8_t * data, size_t len, bool broadcast) = 0;
+
+  //optional callback
+  virtual void onSent(bool success) { log_v("Message reported as sent %s", success ? "successfully" : "unsuccessfully"); }
 };
 
 class ESP_NOW_Class : public Print {

Diff for: libraries/ESP_NOW/src/ESP32_NOW_Serial.cpp

@@ -140,7 +140,7 @@ void ESP_NOW_Serial_Class::flush(){
 }
 
 //RX callback
-void ESP_NOW_Serial_Class::_onReceive(const uint8_t * data, size_t len, bool broadcast){
+void ESP_NOW_Serial_Class::onReceive(const uint8_t * data, size_t len, bool broadcast){
     if(rx_queue == NULL){
         return;
     }
@@ -241,7 +241,7 @@ size_t ESP_NOW_Serial_Class::write(const uint8_t *buffer, size_t size, uint32_t
     return size;
 }
 //TX Done Callback
-void ESP_NOW_Serial_Class::_onSent(bool success){
+void ESP_NOW_Serial_Class::onSent(bool success){
     log_v(MACSTR" : %s", MAC2STR(addr()), success?"OK":"FAIL");
     if(tx_sem == NULL || tx_ring_buf == NULL || !added){
         return;

Diff for: libraries/ESP_NOW/src/ESP32_NOW_Serial.h

@@ -39,8 +39,8 @@ class ESP_NOW_Serial_Class : public Stream, public ESP_NOW_Peer {
     size_t write(const uint8_t *buffer, size_t size){ return write(buffer, size, 1000); }
     size_t write(uint8_t data){ return write(&data, 1); }
     //ESP_NOW_Peer
-    void _onReceive(const uint8_t * data, size_t len, bool broadcast);
-    void _onSent(bool success);
+    void onReceive(const uint8_t * data, size_t len, bool broadcast);
+    void onSent(bool success);
 };