Credentials not saved or loaded correctly

[bramhut]

Hello,
There seem to be issues with saving, deleting or loading the credentials. It appears that the data is loaded or saved at the wrong location in the EEPROM or the data is corrupted. I've expanded your code in issue #307 to also save and delete credentials via serial.

#include <Arduino.h>
#include <ctype.h>
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <AutoConnect.h>

#define DUMP_WIDTH_COLUMNS    8
#define DUMP_WIDTH_REMAIN(x)  (x & (DUMP_WIDTH_COLUMNS - 1))

AutoConnectCredential credit;

void printCredits(){
  Serial.printf("Credential entries:%d\n", credit.entries());
  for (uint8_t e = 0 ; e < credit.entries(); e++) {
    Serial.printf("\nentry #%d:", e);
    station_config_t  entry;
    if (credit.load(e, &entry)) {
      size_t  p = 0;
      while (p < sizeof(station_config_t)) {
        if (!DUMP_WIDTH_REMAIN(p))
          Serial.printf("\n%04x  ", p);
        Serial.printf("%02x ", (uint8_t)*(reinterpret_cast<uint8_t*>(&entry) + p++));
        if (!DUMP_WIDTH_REMAIN(p) || (p >= sizeof(station_config_t))) {
          int sp = DUMP_WIDTH_REMAIN(p) ? 3 * DUMP_WIDTH_REMAIN(p) + 1 : 1;
          Serial.printf("%*c", sp, ' ');
          int w = DUMP_WIDTH_COLUMNS - DUMP_WIDTH_REMAIN(p);
          for (uint8_t cp = p - w; w; cp++, w--)
            Serial.printf("%c", isprint((int)*(reinterpret_cast<uint8_t*>(&entry) + cp)) ? (char)*(reinterpret_cast<uint8_t*>(&entry) + cp) : '.');
        }
      }
      Serial.println();
    }
    else {
      Serial.printf(" loading failed\n");
    }
  }
}

void saveCredit(){
  station_config_t config;
  strcpy( (char*) config.ssid, "TestSSID " );
  char randomChar = (char) random(97,122);
  strncat( (char*) config.ssid, &randomChar, 1);
  strcpy( (char*) config.password , "Password" );
  config.bssid[0] = 0x00;
  config.bssid[1] = 0x01;
  config.bssid[2] = 0x02;
  config.bssid[3] = 0x03;
  config.bssid[4] = 0x04;
  config.bssid[5] = random(0xff);
  config.dhcp = 0;

  credit.save(&config);
}

void delCredit(uint16_t entry = 0){
  if (credit.entries() > 0){
    station_config_t config;
    credit.load(entry, &config);
    credit.del((const char*)&config.ssid[0]);
  }
}

void setup() {
  randomSeed(analogRead(A0));
  delay(1000);
  Serial.begin(115200);
  Serial.println();
  printCredits();
}

void loop() {
  if (Serial.available()){
    String command = Serial.readStringUntil('\n');
    String argument;
    int8_t argumentIndex = command.lastIndexOf(' ');
    if (argumentIndex > 0){
      argument = command.substring(argumentIndex);
      command.remove(argumentIndex);
    }
    if (command.equalsIgnoreCase("Print")){
      printCredits();
    }
    else if (command.equalsIgnoreCase("Save")){
      saveCredit();
      printCredits();
    }
    else if (command.equalsIgnoreCase("Delete") || command.equalsIgnoreCase("Del")){
      if (argument.toInt() >= 0){
        delCredit(argument.toInt());
      }else{
        delCredit();
      }
      printCredits();
    }
  }
}

When saving, or deleting a credential with partly random SSID and BSSID, sometimes the data is corrupted (as seen in the pictures).

Another example, which also shows a shift in some data (SSID).

I'm using an ESP8266 with ESP8266 Arduino framework 3.1.0 using PlatformIO. I've tried using multiple ESP8266's and different versions of AutoConnect (v1.2.2, v1.2.0, v130) but the issue persists.
When using EEPROM.put() and EEPROM.get() in my own sketch, no issues were found.

Thanks in advance.

[bramhut]

After some more debugging I found that AutoConnectCredential::del() doesn't delete the flag for DHCP or Static IP. When using DHCP the byte is set to 0x00. After the first entry is deleted, the SSID of the second entry is preluded with 0x00. Because the del() function looks for the first 0x00 when deleting the SSID or password, the second entry SSID does not get deleted as it immediately encounters 0x00. This means that the while loop for deleting the password actually deletes the SSID. This bug results in the entry not being fully deleted. I solved the issue by replacing

// Erase ip configuration extention
if (_eeprom->read(_dp) == STA_STATIC) {
  for (uint8_t i = 0; i < sizeof(station_config_t::_config); i++)
    _eeprom->write(_dp++, 0xff);
}

with

if (_eeprom->read(_dp) == STA_STATIC) {
  for (uint8_t i = 0; i < sizeof(station_config_t::_config); i++)
    _eeprom->write(_dp++, 0xff);
}
_eeprom->write(_dp++, 0xff);

In AutoConnectCredential.cpp

[Hieromon]

It is incorrect instantiation of AutoConnectCredentail. I'm sure, I have mentioned this note somewhere in the past, but I forgot where I wrote it.
I understand your desire to declare AutoConnectCredential globally. But, AutoConnctCredential for ESP8266 starts EEPROM according to the area size currently used in the constructor. Therefore, the area that has increased since then cannot be determined by AutoConnectCredential. In order for the credential to be accessed correctly, it must be instantiated within the function locally that accesses the AutoConnectCredential.

This topic is a known limitation and will be closed.

[bramhut]

Sorry to insist but the issue is still present when declaring the AutoConnectCredential object locally in each function. I have reperformed the test and the results are the same as before. Although declaring the object globally can certainly cause issues, I still think the issue in this case is in AutoConnectCredential::del(). Could you have a closer look at it? Thanks!

[Hieromon]

@bramhut I was able to reproduce the issue.
You are right. AutoConnectCredential::del has incompletely deleted entry.
I have staged the patch to the brach enhance/v130. Can you evaluate it?
If the issue does not occur in your environment, it will be merged to release v130.
Thank you for your contribution.

[bramhut]

Thank you for the solution, it is working as expected now.