/* * Copyright (c) 1983 Regents of the University of California. * All rights reserved. The Berkeley software License Agreement * specifies the terms and conditions for redistribution. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)gethostent.c 5.3 (Berkeley) 3/9/86"; #endif LIBC_SCCS and not lint #include #include #include #include #include #include #include /* * Internet version. */ #define MAXALIASES 20 #define MAXADDRSIZE (sizeof (u_long)) static FILE *hostf = NULL; static char line[160+1]; static char hostaddr[MAXADDRSIZE]; static struct hostent host; static char *host_aliases[MAXALIASES]; static char *host_addrs[] = { hostaddr, NULL }; /* * The following is shared with gethostnamadr.c */ char *_host_file = "/etc/hosts"; int _host_stayopen; DBM *_host_db; /* set by gethostbyname(), gethostbyaddr() */ static char *any(); sethostent(f) int f; { if (hostf != NULL) rewind(hostf); _host_stayopen |= f; } endhostent() { if (hostf) { fclose(hostf); hostf = NULL; } if (_host_db) { dbm_close(_host_db); _host_db = (DBM *)NULL; } _host_stayopen = 0; } struct hostent * gethostent() { char *p; register char *cp, **q; if (hostf == NULL && (hostf = fopen(_host_file, "r" )) == NULL) return (NULL); again: if ((p = fgets(line, sizeof(line)-1, hostf)) == NULL) return (NULL); if (*p == '#') goto again; cp = any(p, "#\n"); if (cp == NULL) goto again; *cp = '\0'; cp = any(p, " \t"); if (cp == NULL) goto again; *cp++ = '\0'; /* THIS STUFF IS INTERNET SPECIFIC */ host.h_addr_list = host_addrs; *((u_long *)host.h_addr) = inet_addr(p); host.h_length = sizeof (u_long); host.h_addrtype = AF_INET; while (*cp == ' ' || *cp == '\t') cp++; host.h_name = cp; q = host.h_aliases = host_aliases; cp = any(cp, " \t"); if (cp != NULL) *cp++ = '\0'; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (q < &host_aliases[MAXALIASES - 1]) *q++ = cp; cp = any(cp, " \t"); if (cp != NULL) *cp++ = '\0'; } *q = NULL; return (&host); } sethostfile(file) char *file; { _host_file = file; } static char * any(cp, match) register char *cp; char *match; { register char *mp, c; while (c = *cp) { for (mp = match; *mp; mp++) if (*mp == c) return (cp); cp++; } return ((char *)0); }