Re: Porting Bind

[Neal H Walfield <neal@cs.uml.edu>]

=?iso-8859-1?q?Dios=20Del=20Tiempo?= <cronos1_mx@yahoo.com> writes:

> Yes, but as long as I prefer to do the easiest part first, I'll start fix=
> ing
> the MAXHOSTNALELEN issue. To achieve this, I modified Neal's xgethostname=
> .c to
> add the hostnamecpy function; it copies a hostname to another string and
> enforces hostname length limits. Is it correct? If so, is it fine to add =
> it to
> Neal's library, or is better to write it separately? =20

Why do you think that this functionality is generally useful?  I have not heard
of a hostnamecpy function before.

> +int
> +hostnamecpy (char *hostname, char **dest)
> +{
> +  int size =3D 0;
> +  int maxlen =3D 0;
> +  int hostnamelen =3D strlen (hostname);
> +
> +#ifdef MAXHOSTNAMELEN
> +  size =3D MAXHOSTNAMELEN;
> +  maxlen =3D 1;
> +#else /* MAXHOSTNAMELEN */
> +#ifdef _SC_HOST_NAME_MAX
> +  size =3D sysconf (_SC_HOST_NAME_MAX);
> +  maxlen =3D 1;
> +#endif /* _SC_HOST_NAME_MAX */
> +  if (size <=3D 0)
> +    size =3D 255;
> +#endif /* MAXHOSTNAMELEN */
> +
> +  if (maxlen && (hostnamelen > (size + 1)))
> +    return ENAMETOOLONG;

This is broken.  sysconf (_SC_HOST_NAME_MAX) returns -1 on the Hurd.