Improve compatibility of SNMP class trim handling under PHP 8.x

[anarkia1976]

Hi Guys,

i see some errors after latest patches:

2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[141]:api_device_ping_device(), /lib/api_device.php[1543]:cacti_snmp_session_get(), /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::get(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 497
2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[126]:host_reload_query(), /host.php[624]:run_data_query(), /lib/data_query.php[106]:query_snmp_host(), /lib/data_query.php[912]:cacti_snmp_session_get(), /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::get(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 497
2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[126]:host_reload_query(), /host.php[624]:run_data_query(), /lib/data_query.php[106]:query_snmp_host(), /lib/data_query.php[863]:cacti_snmp_session_walk(), /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::walk(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 460
2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[126]:host_reload_query(), /host.php[624]:run_data_query(), /lib/data_query.php[106]:query_snmp_host(), /lib/data_query.php[863]:cacti_snmp_session_walk(), /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::walk(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 460
2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[126]:host_reload_query(), /host.php[624]:run_data_query(), /lib/data_query.php[106]:query_snmp_host(), /lib/data_query.php[863]:cacti_snmp_session_walk(), /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::walk(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 460
2023-07-24 12:26:11 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[126]:host_reload_query(), /host.php[624]:run_data_query(), /lib/data_query.php[106]:query_snmp_host(), /lib/data_query.php[863]:cacti_snmp_session_walk(), /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2023-07-24 12:26:11 - ERROR PHP WARNING: SNMP::walk(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 460
2023-07-24 12:26:00 - CMDPHP PHP ERROR WARNING Backtrace: (/host.php[141]:api_device_ping_device(), /lib/api_device.php[1543]:cacti_snmp_session_get(), /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2023-07-24 12:26:00 - ERROR PHP WARNING: SNMP::get(): Fatal error: Failure in sendto (Invalid argument) in file: /var/www/html/cacti/lib/snmp.php on line: 497

thanks a lot. stefano.

[TheWitness]

Well, that's odd. It's potentially trimming an array. I thought it was simply a string. This may have been introduced by @netniV converting the library to use multiple OID's in a single request. Not sure why it's showing up now. I'll do a little research this morning.

[TheWitness]

Yup. Let me fix it.

[TheWitness]

@anarkia1976, Should be resolved now. Report back after you have tested this as clean and close if all good.

[netniV]

Do we need to check the other functions for trim too?

[TheWitness]

I'm doing that right now.

[TheWitness]

$session->getnext() was affected too.

[TheWitness]

What's odd is that the $session->walk() supports an array too. I don't know anywhere where were are using it that way. We would need to write a test case for that as it would result in a multi-dimensional return array.

[TheWitness]

@netniV, check my last commit on the $session->walk() validation.

[netniV]

Should have made the loops into a a function for cleaner code, You could even have parameters such as a format flag and those of format_snmp_string so that they be passed on to it when format was true instead of trim?

[TheWitness]

Going to mark resolved for now. We can always revisit this later.