getnetgrent.c

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			 break;
		case(4): sprintf((char *)key, "*.*");
			 break;
	}
	return(1);
}
#endif

/*
 * Search for a match in a netgroup.
 */
int
innetgr(group, host, user, dom)
	const char *group, *host, *user, *dom;
{
	char *hst, *usr, *dm;
#ifdef YP
	char *result;
	int resultlen;
	int rv;
#endif
	/* Sanity check */
	
	if (group == NULL || !strlen(group))
		return (0);

#ifdef YP
	_yp_innetgr = 1;
#endif
	setnetgrent(group);
#ifdef YP
	_yp_innetgr = 0;
	/*
	 * If we're in NIS-only mode, do the search using
	 * NIS 'reverse netgroup' lookups.
	 */
	if (_use_only_yp) {
		char _key[MAXHOSTNAMELEN];
		int rot = 0;

		if(yp_get_default_domain(&_netgr_yp_domain))
			return(0);
		while(_buildkey(_key, user ? user : host, dom, &rot)) {
			if (!yp_match(_netgr_yp_domain, user? "netgroup.byuser":
			    "netgroup.byhost", _key, strlen(_key), &result,
			    	&resultlen)) {
				rv = _listmatch(result, group, resultlen);
				free(result);
				if (rv)
					return(1);
				else
					return(0);
			}
		}
#ifdef CHARITABLE
	}
	/*
	 * Couldn't match using NIS-exclusive mode -- try
	 * standard mode.
	 */
	setnetgrent(group);
#else
		return(0);
	}
#endif /* CHARITABLE */
#endif /* YP */
	while (getnetgrent(&hst, &usr, &dm))
		if ((host == NULL || hst == NULL || !strcmp(host, hst)) &&
		    (user == NULL || usr == NULL || !strcmp(user, usr)) &&
		    ( dom == NULL ||  dm == NULL || !strcmp(dom, dm))) {
			endnetgrent();
			return (1);
		}
	endnetgrent();
	return (0);
}

/*
 * Parse the netgroup file setting up the linked lists.
 */
static int
parse_netgrp(group)
	char *group;
{
	register char *spos, *epos;
	register int len, strpos;
#ifdef DEBUG
	register int fields;
#endif
	char *pos, *gpos;
	struct netgrp *grp;
	struct linelist *lp = linehead;

	/*
	 * First, see if the line has already been read in.
	 */
	while (lp) {
		if (!strcmp(group, lp->l_groupname))
			break;
		lp = lp->l_next;
	}
	if (lp == (struct linelist *)0 &&
	    (lp = read_for_group(group)) == (struct linelist *)0)
		return (1);
	if (lp->l_parsed) {
#ifdef DEBUG
		/*
		 * This error message is largely superflous since the
		 * code handles the error condition sucessfully, and
		 * spewing it out from inside libc can actually hose
		 * certain programs.
		 */
		fprintf(stderr, "Cycle in netgroup %s\n", lp->l_groupname);
#endif
		return (1);
	} else
		lp->l_parsed = 1;
	pos = lp->l_line;
	/* Watch for null pointer dereferences, dammit! */
	while (pos != NULL && *pos != '\0') {
		if (*pos == '(') {
			grp = (struct netgrp *)malloc(sizeof (struct netgrp));
			bzero((char *)grp, sizeof (struct netgrp));
			grp->ng_next = grouphead.gr;
			grouphead.gr = grp;
			pos++;
			gpos = strsep(&pos, ")");
#ifdef DEBUG
			fields = 0;
#endif
			for (strpos = 0; strpos < 3; strpos++) {
				if ((spos = strsep(&gpos, ","))) {
#ifdef DEBUG
					fields++;
#endif
					while (*spos == ' ' || *spos == '\t')
						spos++;
					if ((epos = strpbrk(spos, " \t"))) {
						*epos = '\0';
						len = epos - spos;
					} else
						len = strlen(spos);
					if (len > 0) {
						grp->ng_str[strpos] =  (char *)
							malloc(len + 1);
						bcopy(spos, grp->ng_str[strpos],
							len + 1);
					}
				} else {
					/*
					 * All other systems I've tested
					 * return NULL for empty netgroup
					 * fields. It's up to user programs
					 * to handle the NULLs appropriately.
					 */
					grp->ng_str[strpos] = NULL;
				}
			}
#ifdef DEBUG
			/*
			 * Note: on other platforms, malformed netgroup
			 * entries are not normally flagged. While we
			 * can catch bad entries and report them, we should
			 * stay silent by default for compatibility's sake.
			 */
			if (fields < 3)
					fprintf(stderr, "Bad entry (%s%s%s%s%s) in netgroup \"%s\"\n",
						grp->ng_str[NG_HOST] == NULL ? "" : grp->ng_str[NG_HOST],
						grp->ng_str[NG_USER] == NULL ? "" : ",",
						grp->ng_str[NG_USER] == NULL ? "" : grp->ng_str[NG_USER],
						grp->ng_str[NG_DOM] == NULL ? "" : ",",
						grp->ng_str[NG_DOM] == NULL ? "" : grp->ng_str[NG_DOM],
						lp->l_groupname);
#endif
		} else {
			spos = strsep(&pos, ", \t");
			if (parse_netgrp(spos))
				continue;
		}
		/* Watch for null pointer dereferences, dammit! */
		if (pos != NULL)
			while (*pos == ' ' || *pos == ',' || *pos == '\t')
				pos++;
	}
	return (0);
}

/*
 * Read the netgroup file and save lines until the line for the netgroup
 * is found. Return 1 if eof is encountered.
 */
static struct linelist *
read_for_group(group)
	char *group;
{
	register char *pos, *spos, *linep, *olinep;
	register int len, olen;
	int cont;
	struct linelist *lp;
	char line[LINSIZ + 2];
#ifdef YP
	char *result;
	int resultlen;

	while (_netgr_yp_enabled || fgets(line, LINSIZ, netf) != NULL) {
		if (_netgr_yp_enabled) {
			if(!_netgr_yp_domain)
				if(yp_get_default_domain(&_netgr_yp_domain))
					continue;
			if (yp_match(_netgr_yp_domain, "netgroup", group,
					strlen(group), &result, &resultlen)) {
				free(result);
				if (_use_only_yp)
					return ((struct linelist *)0);
				else {
					_netgr_yp_enabled = 0;
					continue;
				}
			}
			snprintf(line, LINSIZ, "%s %s", group, result);
			free(result);
		}
#else
	while (fgets(line, LINSIZ, netf) != NULL) {
#endif
		pos = (char *)&line;
#ifdef YP
		if (*pos == '+') {
			_netgr_yp_enabled = 1;
			continue;
		}
#endif
		if (*pos == '#')
			continue;
		while (*pos == ' ' || *pos == '\t')
			pos++;
		spos = pos;
		while (*pos != ' ' && *pos != '\t' && *pos != '\n' &&
			*pos != '\0')
			pos++;
		len = pos - spos;
		while (*pos == ' ' || *pos == '\t')
			pos++;
		if (*pos != '\n' && *pos != '\0') {
			lp = (struct linelist *)malloc(sizeof (*lp));
			lp->l_parsed = 0;
			lp->l_groupname = (char *)malloc(len + 1);
			bcopy(spos, lp->l_groupname, len);
			*(lp->l_groupname + len) = '\0';
			len = strlen(pos);
			olen = 0;

			/*
			 * Loop around handling line continuations.
			 */
			do {
				if (*(pos + len - 1) == '\n')
					len--;
				if (*(pos + len - 1) == '\\') {
					len--;
					cont = 1;
				} else
					cont = 0;
				if (len > 0) {
					linep = (char *)malloc(olen + len + 1);
					if (olen > 0) {
						bcopy(olinep, linep, olen);
						free(olinep);
					}
					bcopy(pos, linep + olen, len);
					olen += len;
					*(linep + olen) = '\0';
					olinep = linep;
				}
				if (cont) {
					if (fgets(line, LINSIZ, netf)) {
						pos = line;
						len = strlen(pos);
					} else
						cont = 0;
				}
			} while (cont);
			lp->l_line = linep;
			lp->l_next = linehead;
			linehead = lp;

			/*
			 * If this is the one we wanted, we are done.
			 */
			if (!strcmp(lp->l_groupname, group))
				return (lp);
		}
	}
#ifdef YP
	/*
	 * Yucky. The recursive nature of this whole mess might require
	 * us to make more than one pass through the netgroup file.
	 * This might be best left outside the #ifdef YP, but YP is
	 * defined by default anyway, so I'll leave it like this
	 * until I know better.
	 */
	rewind(netf);
#endif
	return ((struct linelist *)0);
}