[unix-history] / usr / src / lib / libc / gen / getgrent.c

/*
* Copyright (c) 1989, 1993
*      The Regents of the University of California.  All rights reserved.
*
* %sccs.include.redist.c%
*/

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getgrent.c  8.1 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <stdio.h>
#include <stdlib.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
start_gr()
{
       if (_gr_fp) {
               rewind(_gr_fp);
               return(1);
       }
       return((_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0);
}

int
setgrent()
{
       return(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
grscan(search, gid, name)
       register int search, gid;
       register char *name;
{
       register char *cp, **m;
       char *bp;
       char *fgets(), *strsep(), *index();

       for (;;) {
               if (!fgets(line, sizeof(line), _gr_fp))
                       return(0);
               bp = line;
               /* skip lines that are too big */
               if (!index(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;
               for (m = _gr_group.gr_mem = members;; ++m) {
                       if (m == &members[MAXGRP - 1]) {
                               *m = NULL;
                               break;
                       }
                       if ((*m = strsep(&bp, ", \n")) == NULL)
                               break;
               }
               return(1);
       }
       /* NOTREACHED */
}