fix(idf): Fix compilation warnings when as component

Author: lucasssvaz

Diff for: cores/esp32/MacAddress.cpp

@@ -67,12 +67,12 @@ bool MacAddress::fromString(const char *buf) {
 
 //Parse user entered string into MAC address
 bool MacAddress::fromString6(const char *buf) {
-  char cs[18];
+  char cs[18];  // 17 + 1 for null terminator
   char *token;
   char *next;  //Unused but required
   int i;
 
-  strncpy(cs, buf, sizeof(cs));  //strtok modifies the buffer: copy to working buffer.
+  strncpy(cs, buf, sizeof(cs) - 1);  //strtok modifies the buffer: copy to working buffer.
 
   for (i = 0; i < 6; i++) {
     token = strtok((i == 0) ? cs : NULL, ":");  //Find first or next token
@@ -86,12 +86,12 @@ bool MacAddress::fromString6(const char *buf) {
 }
 
 bool MacAddress::fromString8(const char *buf) {
-  char cs[24];
+  char cs[24];  // 23 + 1 for null terminator
   char *token;
   char *next;  //Unused but required
   int i;
 
-  strncpy(cs, buf, sizeof(cs));  //strtok modifies the buffer: copy to working buffer.
+  strncpy(cs, buf, sizeof(cs) - 1);  //strtok modifies the buffer: copy to working buffer.
 
   for (i = 0; i < 8; i++) {
     token = strtok((i == 0) ? cs : NULL, ":");  //Find first or next token

Diff for: cores/esp32/esp32-hal-adc.c

@@ -458,7 +458,7 @@ esp_err_t __analogContinuousInit(adc_channel_t *channel, uint8_t channel_num, ad
 
 bool analogContinuous(uint8_t pins[], size_t pins_count, uint32_t conversions_per_pin, uint32_t sampling_freq_hz, void (*userFunc)(void)) {
   adc_channel_t channel[pins_count];
-  adc_unit_t adc_unit;
+  adc_unit_t adc_unit = ADC_UNIT_1;
   esp_err_t err = ESP_OK;
 
   //Convert pins to channels and check if all are ADC1s unit

Diff for: libraries/Ethernet/src/ETH.cpp

@@ -358,11 +358,11 @@ bool ETHClass::begin(eth_phy_type_t type, int32_t phy_addr, int mdc, int mdio, i
 #endif /* CONFIG_ETH_USE_ESP32_EMAC */
 
 #if ETH_SPI_SUPPORTS_CUSTOM
-static void *_eth_spi_init(const void *ctx) {
+__unused static void *_eth_spi_init(const void *ctx) {
   return (void *)ctx;
 }
 
-static esp_err_t _eth_spi_deinit(void *ctx) {
+__unused static esp_err_t _eth_spi_deinit(void *ctx) {
   return ESP_OK;
 }
 
@@ -575,8 +575,8 @@ bool ETHClass::beginSPI(
   }
 
   // Init common MAC and PHY configs to default
-  eth_mac_config_t eth_mac_config = ETH_MAC_DEFAULT_CONFIG();
-  eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG();
+  __unused eth_mac_config_t eth_mac_config = ETH_MAC_DEFAULT_CONFIG();
+  __unused eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG();
 
   // Update PHY config based on board specific configuration
   phy_config.phy_addr = phy_addr;