Re: socklen_t

[Albert Chin]

On Thu, Sep 01, 2005 at 01:28:39PM +0200, Simon Josefsson wrote:
> Albert Chin <address@hidden> writes:
> 
> > We created the following macro for curl. It's been tested on the
> > following systems:
> 
> Has the copyright been assigned to the FSF?

No. I'd like to see a liberal license with this though. Curl is under
a very liberal license. We'd like to see other programs use this macro
for detecting socklen_t as well (lftp has adopted a derivative of it
and KDE I think has).

> > dnl Check for socklen_t: historically on BSD it is an int, and in
> > dnl POSIX 1g it is a type of its own, but some platforms use different
> > dnl types for the argument to getsockopt, getpeername, etc.  So we
> > dnl have to test to find something that will work.
> > AC_DEFUN([TYPE_SOCKLEN_T],
> > [
> >    AC_CHECK_TYPE([socklen_t], ,[
> >       AC_MSG_CHECKING([for socklen_t equivalent])
> >       AC_CACHE_VAL([socklen_t_equiv],
> >       [
> >          # Systems have either "struct sockaddr *" or
> >          # "void *" as the second argument to getpeername
> >          socklen_t_equiv=
> >          for arg2 in "struct sockaddr" void; do
> >             for t in int size_t unsigned long "unsigned long"; do
> >                AC_TRY_COMPILE([
> >                   #include <sys/types.h>
> >                   #include <sys/socket.h>
> >
> >                   int getpeername (int, $arg2 *, $t *);
> 
> A bit weird approach of checking for a compatible type, perhaps, but
> if it works, then I'm all for it.  Bruno, what do you think?

BTW, having socklen_t doesn't mean it's used by some of the networking
functions. Check this out:
  http://bugs.kde.org/show_bug.cgi?id=78238
  http://www.mail-archive.com/address@hidden/msg01246.html

$ uname -a
HP-UX hulk B.11.11 U 9000/785 2010914556 unlimited-user license

$ cat a.c
#include <sys/types.h>
#include <sys/socket.h>

$ cc -E a.c | grep socklen_t
typedef size_t socklen_t;
        socklen_t msg_namelen;
        socklen_t msg_controllen;

$ cc -E -D_XOPEN_SOURCE_EXTENDED a.c | grep socklen_t
typedef size_t socklen_t;
        socklen_t msg_namelen;
        socklen_t msg_controllen;
        socklen_t cmsg_len;
   extern int accept (int, struct sockaddr *, socklen_t *) ;
   extern int bind (int, const struct sockaddr *, socklen_t) ;
   extern int connect (int, const struct sockaddr *, socklen_t) ;
   extern int getpeername (int, struct sockaddr *, socklen_t *) ;
   extern int getsockname (int, struct sockaddr *, socklen_t *) ;
   extern int getsockopt (int, int, int, void *, socklen_t *) ;
   extern ssize_t recvfrom (int, void *, size_t, int, struct sockaddr *, 
socklen_t *) ;
   extern ssize_t sendto (int, const void *, size_t, int, const struct sockaddr 
*, socklen_t) ;
   extern int setsockopt (int, int, int, const void *, socklen_t) ;

-- 
albert chin (address@hidden)