AP restarts when name (SSID) is unchanged after saving WiFi settings (should reconnects when SSID changed)

[drmaus83]

WLED/wled00/set.cpp

Line 113 in 54e3317

if (!strcmp(oldSSID, apSSID) && apActive) forceReconnect = true;

I'm working on my own little fork of WLED that uses only ap mode and i noticed the check seems to be inverted. instead of resetting when the name is changed it always resets if the name is unchanged.

I worry that there may be other things that rely on this mechanism (even if its incorrect) because it seems like changing settings and saving restarts the ap but its not actually doing that if you change the name only

[softhack007]

@drmaus83 Maybe you misunderstood the return value of strncmp? Its Zero if both strings compare equal.

Zero = false, so !strncmp(a,a) == true means two strings are equal.

https://en.cppreference.com/c/string/byte/strncmp

[softhack007]

Nevertheless, you might have found a bug. If the intention of the line is to trigger a reconnect when SSID changed while AP is active, then the condition should be

  if ((strcmp(oldSSID, apSSID) !=0)  && apActive) forceReconnect = true; 

The problem is that x != 0 and !x are the opposite of each other in this case, and not the same expression.

[drmaus83]

@softhack007 strncmp returns 0 when all characters are the same and returns a number (which evaluates to true) when they are different. So you can just remove the ! inversion or I like the explicit comparisons better like the one you posted with this evaluation

!=0

thank you for giving it a second look after initially closing it I already feel like I'm out of my league here and arguing with people at much higher skill levels is !fun (pun intended)

[DedeHai]

@softhack007 confirmed, this should be !=0, seems to be a long standing bug. thanks @drmaus83 for digging this up, should be an easy fix. I will do a commit directly to main and cherry pick to 16_x

[DedeHai]

fixed in 7b9afe9