Merge branch 'i2c_slave_by_bjoham' of https://github.com/thinx-cloud/Arduino into i2c_slave_by_bjoham

* 'i2c_slave_by_bjoham' of https://github.com/thinx-cloud/Arduino:
  Update debugging.rst (esp8266#5234)
  ESP8266httpClient crash-on-destructor bugfix (esp8266#5220)
  Add stack repainting call to ESP class (esp8266#5221)

Author: Matěj Sychra

cores/esp8266/Esp.cpp

@@ -183,6 +183,11 @@ uint32_t EspClass::getFreeContStack()
     return cont_get_free_stack(g_pcont);
 }
 
+void EspClass::resetFreeContStack()
+{
+    cont_repaint_stack(g_pcont);
+}
+
 uint32_t EspClass::getChipId(void)
 {
     return system_get_chip_id();

cores/esp8266/Esp.h

@@ -111,6 +111,7 @@ class EspClass {
         void getHeapStats(uint32_t* free = nullptr, uint16_t* max = nullptr, uint8_t* frag = nullptr);
 
         uint32_t getFreeContStack();
+        void resetFreeContStack();
 
         const char * getSdkVersion();
         String getCoreVersion();

cores/esp8266/cont.h

@@ -74,6 +74,12 @@ int cont_get_free_stack(cont_t* cont);
 // continuation stack
 bool cont_can_yield(cont_t* cont);
 
+// Repaint the stack from the current SP to the end, to allow individual
+// routines' stack usages to be calculated by re-painting, checking current
+// free, running the routine, then checking the max free
+void cont_repaint_stack(cont_t *cont);
+
+
 #ifdef __cplusplus
 }
 #endif

cores/esp8266/cont_util.c

@@ -64,3 +64,18 @@ bool ICACHE_RAM_ATTR cont_can_yield(cont_t* cont) {
     return !ETS_INTR_WITHINISR() &&
            cont->pc_ret != 0 && cont->pc_yield == 0;
 }
+
+// No need for this to be in IRAM, not expected to be IRQ called
+void cont_repaint_stack(cont_t *cont)
+{
+    register uint32_t *sp asm("a1");
+    // Ensure 64 bytes adjacent to the current SP don't get touched to endure
+    // we don't accidentally trounce over locals or IRQ temps.
+    uint32_t sp_safe = CONT_STACKSIZE/4 - ((sp - &cont->stack[0] - 64)/4);
+
+    // Fill stack with magic values
+    for(uint32_t pos = 0; pos < sp_safe; pos++)
+    {
+        cont->stack[pos] = CONT_STACKGUARD;
+    }
+}

doc/Troubleshooting/debugging.rst

@@ -74,7 +74,7 @@ Debug Level
 All defines for the different levels starts with ``DEBUG_ESP_``
 
 a full list can be found here in the
-`boards.txt <https://github.com/esp8266/Arduino/blob/master/boards.txt#L180>`__
+`boards.txt <https://github.com/esp8266/Arduino/blob/master/tools/boards.txt.py#L1045-L1047>`__
 
 Example for own debug messages
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

libraries/ESP8266HTTPClient/examples/BasicHttpsClient/BasicHttpsClient.ino

@@ -41,13 +41,14 @@ void loop() {
   // wait for WiFi connection
   if ((WiFiMulti.run() == WL_CONNECTED)) {
 
-    BearSSL::WiFiClientSecure client;
-    client.setFingerprint(fingerprint);
+    BearSSL::WiFiClientSecure *client = new BearSSL::WiFiClientSecure;
+
+    client->setFingerprint(fingerprint);
 
     HTTPClient https;
 
     Serial.print("[HTTPS] begin...\n");
-    if (https.begin(client, "https://jigsaw.w3.org/HTTP/connection.html")) {  // HTTPS
+    if (https.begin(*client, "https://jigsaw.w3.org/HTTP/connection.html")) {  // HTTPS
 
 
       Serial.print("[HTTPS] GET...\n");
@@ -72,6 +73,8 @@ void loop() {
     } else {
       Serial.printf("[HTTPS] Unable to connect\n");
     }
+
+    delete client;
   }
 
   delay(10000);

libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp

@@ -123,7 +123,7 @@ HTTPClient::HTTPClient()
 HTTPClient::~HTTPClient()
 {
     if(_client) {
-        _client->stop();
+        DEBUG_HTTPCLIENT("[HTTP-Client][~HTTPClient] end() not called before destruction of HTTPClient\n");
     }
     if(_currentHeaders) {
         delete[] _currentHeaders;
@@ -196,7 +196,7 @@ bool HTTPClient::begin(WiFiClient &client, String host, uint16_t port, String ur
 #ifdef HTTPCLIENT_1_1_COMPATIBLE
 bool HTTPClient::begin(String url, String httpsFingerprint)
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     _port = 443;
@@ -214,7 +214,7 @@ bool HTTPClient::begin(String url, String httpsFingerprint)
 
 bool HTTPClient::begin(String url, const uint8_t httpsFingerprint[20])
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     _port = 443;
@@ -237,7 +237,7 @@ bool HTTPClient::begin(String url, const uint8_t httpsFingerprint[20])
  */
 bool HTTPClient::begin(String url)
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     _port = 80;
@@ -299,7 +299,7 @@ bool HTTPClient::beginInternal(String url, const char* expectedProtocol)
 #ifdef HTTPCLIENT_1_1_COMPATIBLE
 bool HTTPClient::begin(String host, uint16_t port, String uri)
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     clear();
@@ -325,7 +325,7 @@ bool HTTPClient::begin(String host, uint16_t port, String uri, bool https, Strin
 
 bool HTTPClient::begin(String host, uint16_t port, String uri, String httpsFingerprint)
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     clear();
@@ -343,7 +343,7 @@ bool HTTPClient::begin(String host, uint16_t port, String uri, String httpsFinge
 
 bool HTTPClient::begin(String host, uint16_t port, String uri, const uint8_t httpsFingerprint[20])
 {
-    if(_client) _canReuse = false;
+    _canReuse = false;
     end();
 
     clear();
@@ -367,6 +367,7 @@ bool HTTPClient::begin(String host, uint16_t port, String uri, const uint8_t htt
  */
 void HTTPClient::end(void)
 {
+    _canReuse = false;
     disconnect();
     clear();
 }

libraries/ESP8266WiFi/examples/BearSSL_Validation/BearSSL_Validation.ino

@@ -38,6 +38,8 @@ void fetchURL(BearSSL::WiFiClientSecure *client, const char *host, const uint16_
     path = "/";
   }
 
+  ESP.resetFreeContStack();
+  uint32_t freeStackStart = ESP.getFreeContStack();
   Serial.printf("Trying: %s:443...", host);
   client->connect(host, port);
   if (!client->connected()) {
@@ -72,7 +74,8 @@ void fetchURL(BearSSL::WiFiClientSecure *client, const char *host, const uint16_
     } while (millis() < to);
   }
   client->stop();
-  Serial.printf("\n-------\n\n");
+  uint32_t freeStackEnd = ESP.getFreeContStack();
+  Serial.printf("\nCONT stack used: %d\n-------\n\n", freeStackStart - freeStackEnd);
 }
 
 void fetchNoConfig() {