Proper patching source code with HOST_NAME_MAX usage

[Matthias Petermann <mp%petermann-it.de@localhost>]

Hi there,

I developed a patch over the weekend to upgrade net/rdesktop to the 
current version 1.9.0. The version currently in pkgsrc has an unpleasant 
bug (https://github.com/rdesktop/rdesktop/issues/17)

The patch works, but I would like to clarify one detail before 
submitting. In the file xwin.c a variable hostname is defined in the 
method set_wm_client_machine in the following way:

char hostname [HOST_NAME_MAX];

The macro HOST_NAME_MAX does not exist in NetBSD. Instead, I read 
sysconf (_SC_HOST_NAME_MAX) should be used. My C course was two decades 
ago, but if I remember correctly I can't just use it instead of 
HOST_NAME_MAX.

So my question is: what is the best way to deal with it?

a) Use of MAXHOSTNAMELEN from sys/param.h

b) Convert the variable into a pointer variable and use allocation of 
the appropriate length at runtime? Disadvantage: memory would actually 
have to be released again, i.e. more intervention in the original source 
code than I actually want to do ..

c) is there anything more elegant that I don't know about yet?

I have essentially oriented myself towards [1] and appreciate comments.

Best wishes
Matthias


[1] https://lists.gnu.org/archive/html/bug-gnulib/2009-08/msg00108.html

--
Petermann IT / M. Petermann <mp%petermann-it.de@localhost> | www.petermann-it.de
Wildparkring 13, 01458 Ottendorf-Okrilla | Tel.: +49 (0)35205 597 991