diff options
Diffstat (limited to 'inet/ether_ntoh.c')
-rw-r--r-- | inet/ether_ntoh.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/inet/ether_ntoh.c b/inet/ether_ntoh.c new file mode 100644 index 0000000000..26a4e471ad --- /dev/null +++ b/inet/ether_ntoh.c @@ -0,0 +1,85 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. +This file is part of the GNU C Library. +Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +#include <netinet/ether.h> +#include <netinet/if_ether.h> + +#include "../nss/nsswitch.h" + +/* Because the `ethers' lookup does not fit so well in the scheme so + we define a dummy struct here which helps us to use the available + functions. */ +struct etherent +{ + const char *e_name; + struct ether_addr e_addr; +}; + + +/* Type of the lookup function we need here. */ +typedef int (*lookup_function) (const struct ether_addr *, struct etherent *, + char *, int); + + +int +ether_ntohost (char *hostname, const struct ether_addr *addr) +{ + static service_user *startp = NULL; + static lookup_function start_fct; + service_user *nip; + lookup_function fct; + int no_more; + int result; + enum nss_status status = NSS_STATUS_UNAVAIL; + struct etherent etherent; + + if (startp == NULL) + { + no_more = __nss_ethers_lookup (&nip, "getntohost_r", (void **) &fct); + if (no_more) + startp = (service_user *) -1; + else + { + startp = nip; + start_fct = fct; + } + } + else + { + fct = start_fct; + no_more = (nip = startp) == (service_user *) -1; + } + + while (no_more == 0) + { + char buffer[1024]; + + status = (*fct) (addr, ðerent, buffer, sizeof buffer); + + no_more = __nss_next (&nip, "getntohost_r", (void **) &fct, status, 0); + } + + if (status == NSS_STATUS_SUCCESS) + /* XXX This is a potential cause of trouble because the size of + the HOSTNAME buffer is not known but the interface does not + provide this information. */ + strcpy (hostname, etherent.e_name); + + return status == NSS_STATUS_SUCCESS ? 0 : -1; +} |