text: /*	$NetBSD: getgrent.c,v 1.2 1995/10/13 18:10:23 gwr Exp $	*/
  
  /*
   * Copyright (c) 1989, 1993
   *	The Regents of the University of California.  All rights reserved.
   * Portions Copyright (c) 1994, Jason Downs. All Rights Reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  /*
   * Copied from:  lib/libc/gen/getgrent.c
   * and then gutted, leaving only /etc/group support.
   */
  
  #include <sys/types.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <grp.h>
  
  static FILE *_gr_fp;
  static struct group _gr_group;
  static int _gr_stayopen;
  static int grscan(), start_gr();
  
  #define	MAXGRP		200
  static char *members[MAXGRP];
  #define	MAXLINELENGTH	1024
  static char line[MAXLINELENGTH];
  
  struct group *
  getgrent()
  {
  	if (!_gr_fp && !start_gr() || !grscan(0, 0, NULL))
  		return(NULL);
  	return(&_gr_group);
  }
  
  struct group *
  getgrnam(name)
  	const char *name;
  {
  	int rval;
  
  	if (!start_gr())
  		return(NULL);
  	rval = grscan(1, 0, name);
  	if (!_gr_stayopen)
  		endgrent();
  	return(rval ? &_gr_group : NULL);
  }
  
  struct group *
  #ifdef __STDC__
  getgrgid(gid_t gid)
  #else
  getgrgid(gid)
  	gid_t gid;
  #endif
  {
  	int rval;
  
  	if (!start_gr())
  		return(NULL);
  	rval = grscan(1, gid, NULL);
  	if (!_gr_stayopen)
  		endgrent();
  	return(rval ? &_gr_group : NULL);
  }
  
  static int
  start_gr()
  {
  	if (_gr_fp) {
  		rewind(_gr_fp);
  		return(1);
  	}
  	return((_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0);
  }
  
  void
  setgrent()
  {
  	(void) setgroupent(0);
  }
  
  int
  setgroupent(stayopen)
  	int stayopen;
  {
  	if (!start_gr())
  		return(0);
  	_gr_stayopen = stayopen;
  	return(1);
  }
  
  void
  endgrent()
  {
  	if (_gr_fp) {
  		(void)fclose(_gr_fp);
  		_gr_fp = NULL;
  	}
  }
  
  static int
  grscan(search, gid, name)
  	register int search, gid;
  	register char *name;
  {
  	register char *cp, **m;
  	char *bp;
  
  	for (;;) {
  		if (!fgets(line, sizeof(line), _gr_fp))
  			return(0);
  		bp = line;
  		/* skip lines that are too big */
  		if (!strchr(line, '\n')) {
  			int ch;
  
  			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
  				;
  			continue;
  		}
  		_gr_group.gr_name = strsep(&bp, ":\n");
  		if (search && name && strcmp(_gr_group.gr_name, name))
  			continue;
  		_gr_group.gr_passwd = strsep(&bp, ":\n");
  		if (!(cp = strsep(&bp, ":\n")))
  			continue;
  		_gr_group.gr_gid = atoi(cp);
  		if (search && name == NULL && _gr_group.gr_gid != gid)
  			continue;
  		cp = NULL;
  		if (bp == NULL)
  			continue;
  		for (m = _gr_group.gr_mem = members;; bp++) {
  			if (m == &members[MAXGRP - 1])
  				break;
  			if (*bp == ',') {
  				if (cp) {
  					*bp = '\0';
  					*m++ = cp;
  					cp = NULL;
  				}
  			} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
  				if (cp) {
  					*bp = '\0';
  					*m++ = cp;
  				}
  				break;
  			} else if (cp == NULL)
  				cp = bp;
  		}
  		*m = NULL;
  		return(1);
  	}
  	/* NOTREACHED */
  }
  