/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*LINTLIBRARY*/

/*
 * readdir -- C library extension routine
 */

#include        <sys/types.h>
#include        <sys/dir.h>
#include        <sys/dirent.h>
#include        <limits.h>
#include        <string.h>
#include        <errno.h>
#include        "libc.h"

static struct direct    dc;
static struct direct64  dc64;

static struct direct64 *
internal_readdir(DIR *dirp)
{
        struct dirent64 *dp;    /* -> directory data */
        int saveloc = 0;

        if (dirp->dd_size != 0) {
                dp = (struct dirent64 *)&dirp->dd_buf[dirp->dd_loc];
                saveloc = dirp->dd_loc;   /* save for possible EOF */
                dirp->dd_loc += dp->d_reclen;
        }
        if (dirp->dd_loc >= dirp->dd_size)
                dirp->dd_loc = dirp->dd_size = 0;

        if (dirp->dd_size == 0 &&       /* refill buffer */
            (dirp->dd_size = getdents64(dirp->dd_fd,
            (struct dirent64 *)dirp->dd_buf, DIRBUF)) <= 0) {
                if (dirp->dd_size == 0) /* This means EOF */
                        dirp->dd_loc = saveloc;  /* EOF so save for telldir */
                return (NULL);  /* error or EOF */
        }

        dp = (struct dirent64 *)&dirp->dd_buf[dirp->dd_loc];

        /* Copy dirent into direct */
        dc64.d_ino = dp->d_ino;
        dc64.d_reclen = dp->d_reclen;
        dc64.d_namlen = (ushort_t)strlen(dp->d_name);
        if (dc64.d_namlen > MAXNAMLEN) {
                errno = ENAMETOOLONG;
                return (NULL);
        }
        (void) strcpy(dc64.d_name, dp->d_name);

        return (&dc64);
}

struct direct *
readdir(DIR *dirp)
{
        if (internal_readdir(dirp) == NULL)
                return (NULL);

        /* Check for overflows */
        if (dc64.d_ino > SIZE_MAX) {
                errno = EOVERFLOW;
                return (NULL);
        }

        /* Copy dirent into direct */
        dc.d_ino = dc64.d_ino;
        dc.d_reclen = dc64.d_reclen - 4;
        dc.d_namlen = dc64.d_namlen;
        (void) strcpy(dc.d_name, dc64.d_name);

        return (&dc);
}

#if !defined(_LP64)
struct direct64 *
readdir64(DIR *dirp)
{
        return (internal_readdir(dirp));
}
#endif