diff options
Diffstat (limited to 'pith/osdep/domnames.c')
| -rw-r--r-- | pith/osdep/domnames.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/pith/osdep/domnames.c b/pith/osdep/domnames.c new file mode 100644 index 00000000..47a95278 --- /dev/null +++ b/pith/osdep/domnames.c @@ -0,0 +1,145 @@ +#if !defined(lint) && !defined(DOS) +static char rcsid[] = "$Id: domnames.c 1176 2008-09-29 21:16:42Z hubert@u.washington.edu $"; +#endif + +/* + * ======================================================================== + * Copyright 2008 University of Washington + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * ======================================================================== + */ + +#include <system.h> +#include <general.h> + +#include "domnames.h" + + +/*---------------------------------------------------------------------- + Get the current host and domain names + + Args: hostname -- buffer to return the hostname in + hsize -- size of buffer above + domainname -- buffer to return domain name in + dsize -- size of buffer above + + Result: The system host and domain names are returned. If the full host + name is akbar.cac.washington.edu then the domainname is + cac.washington.edu. + +On Internet connected hosts this look up uses /etc/hosts and DNS to +figure all this out. On other less well connected machines some other +file may be read. If there is no notion of a domain name the domain +name may be left blank. On a PC where there really isn't a host name +this should return blank strings. The .pinerc will take care of +configuring the domain names. That is, this should only return the +native system's idea of what the names are if the system has such +a concept. + ----*/ +void +getdomainnames(char *hostname, int hsize, char *domainname, int dsize) +{ +#if HAVE_NETDB_H + char *dn, hname[MAX_ADDRESS+1]; + struct hostent *he; + char **alias; + char *maybe = NULL; + + if(gethostname(hname, MAX_ADDRESS)) + hname[0] = 0xff; + + /* sanity check of hostname string */ + for(dn = hname; (*dn > 0x20) && (*dn < 0x7f); ++dn) + ; + + if(*dn){ /* if invalid string returned, return "unknown" */ + strncpy(domainname, "unknown", dsize-1); + domainname[dsize-1] = '\0'; + strncpy(hostname, "unknown", hsize-1); + hostname[hsize-1] = '\0'; + return; + } + + he = gethostbyname(hname); + hostname[0] = '\0'; + + if(he == NULL){ + strncpy(hostname, hname, hsize-1); + hostname[hsize-1] = '\0'; + } + else{ + /* + * If no dot in hostname it may be the case that there + * is an alias which is really the fully-qualified + * hostname. This could happen if the administrator has + * (incorrectly) put the unqualified name first in the + * hosts file, for example. The problem with looking for + * an alias with a dot is that now we're guessing, since + * the aliases aren't supposed to be the official hostname. + * We'll compromise and only use an alias if the primary + * name has no dot and exactly one of the aliases has a + * dot. + */ + strncpy(hostname, he->h_name, hsize-1); + hostname[hsize-1] = '\0'; + if(strchr(hostname, '.') == NULL){ /* no dot in hostname */ + for(alias = he->h_aliases; *alias; alias++){ + if(strchr(*alias, '.') != NULL){ /* found one */ + if(maybe){ /* oops, this is the second one */ + maybe = NULL; + break; + } + else + maybe = *alias; + } + } + + if(maybe){ + strncpy(hostname, maybe, hsize-1); + hostname[hsize-1] = '\0'; + } + } + } + + hostname[hsize-1] = '\0'; + + if((dn = strchr(hostname, '.')) != NULL) + strncpy(domainname, dn+1, dsize-1); + else + strncpy(domainname, hostname, dsize-1); + + domainname[dsize-1] = '\0'; +#else /* !HAVE_NETDB_H */ + /* should only be _WINDOWS */ + +#ifdef _WINDOWS + char *p; + extern char *mylocalhost(void); + + hostname[0] = domainname[0] = '\0'; + if(p = mylocalhost()) + snprintf(hostname, hsize, "%s", p); + + snprintf(domainname, dsize, "%s", + (hostname[0] && hostname[0] != '[' && (p = strchr(hostname,'.'))) + ? p+1 : hostname); +#else /* !_WINDOWS */ + + char *p, hname[MAX_ADDRESS+1]; + + hostname[0] = domainname[0] = '\0'; + if(gethostname(hname, MAX_ADDRESS) == 0) + snprintf(hostname, hsize, "%s", hname); + + snprintf(domainname, dsize, "%s", + (hostname[0] && hostname[0] != '[' && (p = strchr(hostname,'.'))) + ? p+1 : hostname); +#endif /* !_WINDOWS */ +#endif /* !HAVE_NETDB_H */ +} |