fixes

[sticilface]

This adds the implementation for Syslog &Syslog::server(IPAddress ip, uint16_t port) which is missing.
adds a check to use _ip if _server is null
adds a new method to use PSTR() within Syslog & vlogf_P(uint16_t pri, PGM_P formatP, ...) this saves RAM and is quite cool.

[sticilface]

I used this post to fix the vsnprintf_P on the other platform but can't test if it actually works
bportaluri/WiFiEsp#27

[arcao]

This adds the implementation for Syslog &Syslog::server(IPAddress ip, uint16_t port) which is missing.
adds a check to use _ip if _server is null

I will fix it in version 2.1.0

adds a new method to use PSTR() within Syslog & vlogf_P(uint16_t pri, PGM_P formatP, ...) this saves RAM and is quite cool.

Yes, I've think about the same. I will definitely add it to version 2.1.0. But your implementation should be separated into two methods: logf_P(uint16_t pri, PGM_P formatP, ...) and vlogf_P(uint16_t pri, PGM_P formatP, va_list args). The v there means va_list.

[arcao]

I made my own implementation of logf_P anyway thanks for PR.

[sticilface]

no problem :)