Subversion Repositories planix.SVN

#include <stdio.h>
#include <grp.h>
#include <stdlib.h>

#define CL      ':'
#define CM      ','
#define NL      '\n'
#define MAXGRP  100

static char GROUP[] = "/etc/group";
static FILE *grf = NULL;
static char line[BUFSIZ+1];
static struct group group;
static char *gr_mem[MAXGRP];

void
setgrent(void)
{
        if( !grf )
                grf = fopen( GROUP, "r" );
        else
                rewind( grf );
}

void
endgrent(void)
{
        if( grf ){
                fclose( grf );
                grf = NULL;
        }
}

static char *
grskip(register char *p, register c)
{
        while( *p && *p != c ) ++p;
        if( *p ) *p++ = 0;
        return( p );
}

struct group *
getgrent()
{
        register char *p, **q;

        if( !grf && !(grf = fopen( GROUP, "r" )) )
                return(NULL);
        if( !(p = fgets( line, BUFSIZ, grf )) )
                return(NULL);
        group.gr_name = p;
        p = grskip(p,CL); /* passwd */
        group.gr_gid = atoi(p = grskip(p,CL));
        group.gr_mem = gr_mem;
        p = grskip(p,CL);
        grskip(p,NL);
        q = gr_mem;
        while( *p ){
                *q++ = p;
                p = grskip(p,CM);
        }
        *q = NULL;
        return( &group );
}