From bdfbe4093e56160b8d3f7fee13aeaea2504d1763 Mon Sep 17 00:00:00 2001
From: pennam <m.pennasilico@arduino.cc>
Date: Thu, 19 Oct 2023 11:37:49 +0200
Subject: [PATCH] Add protected methods to init variables and handle crc

---
 src/Arduino_ESP32_OTA.cpp | 47 ++++++++++++++++++++++++++++++++++-----
 src/Arduino_ESP32_OTA.h   |  9 +++++++-
 2 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/src/Arduino_ESP32_OTA.cpp b/src/Arduino_ESP32_OTA.cpp
index 7a95dfb..2b32a21 100644
--- a/src/Arduino_ESP32_OTA.cpp
+++ b/src/Arduino_ESP32_OTA.cpp
@@ -47,14 +47,21 @@ Arduino_ESP32_OTA::Arduino_ESP32_OTA()
 
 Arduino_ESP32_OTA::Error Arduino_ESP32_OTA::begin()
 {
+  /* initialize private variables */
+  otaInit();
 
   /* ... initialize CRC ... */
-  _crc32 = 0xFFFFFFFF;
+  crc32Init();
 
   if(!isCapable()) {
     DEBUG_ERROR("%s: board is not capable to perform OTA", __FUNCTION__);
     return Error::NoOtaStorage;
   }
+
+  if(Update.isRunning()) {
+    Update.abort();
+    DEBUG_DEBUG("%s: Aborting running update", __FUNCTION__);
+  }
   
   if(!Update.begin(UPDATE_SIZE_UNKNOWN)) {
     DEBUG_ERROR("%s: failed to initialize flash update", __FUNCTION__);
@@ -89,7 +96,7 @@ uint8_t Arduino_ESP32_OTA::read_byte_from_network()
     }
     if (_client->available()) {
       const uint8_t data = _client->read();
-      _crc32 = crc_update(_crc32, &data, 1);
+      crc32Update(data);
       return data;
     }
   }
@@ -243,10 +250,10 @@ int Arduino_ESP32_OTA::download(const char * ota_url)
 
 Arduino_ESP32_OTA::Error Arduino_ESP32_OTA::update()
 {
-  /* ... then finalise ... */
-  _crc32 ^= 0xFFFFFFFF;
+  /* ... then finalize ... */
+  crc32Finalize();
 
-  if(_crc32 != _ota_header.header.crc32) {
+  if(!crc32Verify()) {
     DEBUG_ERROR("%s: CRC32 mismatch", __FUNCTION__);
     return Error::OtaHeaderCrc;
   }
@@ -270,3 +277,33 @@ bool Arduino_ESP32_OTA::isCapable()
   const esp_partition_t * ota_1  = esp_partition_find_first(ESP_PARTITION_TYPE_APP, ESP_PARTITION_SUBTYPE_APP_OTA_1, NULL);
   return ((ota_0 != nullptr) && (ota_1 != nullptr));
 }
+
+/******************************************************************************
+   PROTECTED MEMBER FUNCTIONS
+ ******************************************************************************/
+
+void Arduino_ESP32_OTA::otaInit()
+{
+  _ota_size = 0;
+  _ota_header = {0};
+}
+
+void Arduino_ESP32_OTA::crc32Init()
+{
+  _crc32 = 0xFFFFFFFF;
+}
+
+void Arduino_ESP32_OTA::crc32Update(const uint8_t data)
+{
+  _crc32 = crc_update(_crc32, &data, 1);
+}
+
+void Arduino_ESP32_OTA::crc32Finalize()
+{
+  _crc32 ^= 0xFFFFFFFF;
+}
+
+bool Arduino_ESP32_OTA::crc32Verify()
+{
+  return (_crc32 == _ota_header.header.crc32);
+}
diff --git a/src/Arduino_ESP32_OTA.h b/src/Arduino_ESP32_OTA.h
index b34aa88..fac2aeb 100644
--- a/src/Arduino_ESP32_OTA.h
+++ b/src/Arduino_ESP32_OTA.h
@@ -82,8 +82,15 @@ class Arduino_ESP32_OTA
   void reset();
   static bool isCapable();
 
-private:
+protected:
+
+  void otaInit();
+  void crc32Init();
+  void crc32Update(const uint8_t data);
+  void crc32Finalize();
+  bool crc32Verify();
 
+private:
   Client * _client;
   OtaHeader _ota_header;
   size_t _ota_size;