/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#include        "lint.h"
#include        <mtlib.h>
#include        <stdio.h>
#include        <stdlib.h>
#include        <errno.h>
#include        <sys/types.h>
#include        <sys/stat.h>
#include        <sys/vfstab.h>
#include        <string.h>
#include        <thread.h>
#include        <synch.h>
#include        <strings.h>
#include        <libc.h>
#include        "tsd.h"


#define GETTOK_R(xx, ll, tmp)\
        if ((vp->xx = (char *)strtok_r(ll, sepstr, tmp)) == NULL)\
                return (VFS_TOOFEW);\
        if (strcmp(vp->xx, dash) == 0)\
                vp->xx = NULL
#define GETTOK(xx, ll)\
        if ((vp->xx = strtok(ll, sepstr)) == NULL)\
                return (VFS_TOOFEW);\
        if (strcmp(vp->xx, dash) == 0)\
                vp->xx = NULL
#define DIFF(xx)\
        (vrefp->xx != NULL && (vgetp->xx == NULL ||\
            strcmp(vrefp->xx, vgetp->xx) != 0))
#define SDIFF(xx, typem, typer)\
        (vgetp->xx == NULL || stat64(vgetp->xx, &statb) == -1 ||\
        (statb.st_mode & S_IFMT) != typem ||\
            statb.st_rdev != typer)

static const char       sepstr[] = " \t\n";
static const char       dash[] = "-";

static int      getaline(char *, FILE *);

int
getvfsspec(FILE *fd, struct vfstab *vgetp, char *special)
{
        int     ret, bstat;
        mode_t  bmode;
        dev_t   brdev;
        struct stat64   statb;


        if (special && stat64(special, &statb) == 0 &&
            ((bmode = (statb.st_mode & S_IFMT)) == S_IFBLK ||
            bmode == S_IFCHR)) {
                bstat = 1;
                brdev = statb.st_rdev;
        } else
                bstat = 0;

        while ((ret = getvfsent(fd, vgetp)) == 0 &&
            ((bstat == 0 &&
            (special != NULL && (vgetp->vfs_special == NULL ||
            strcmp(special, vgetp->vfs_special) != 0))) ||
            (bstat == 1 &&
            (vgetp->vfs_special == NULL ||
            stat64(vgetp->vfs_special, &statb) == -1 ||
            (statb.st_mode & S_IFMT) != bmode ||
            statb.st_rdev != brdev))))
                ;
        return (ret);
}

int
getvfsfile(FILE *fd, struct vfstab *vp, char *mountp)
{
        struct vfstab   vv;

        bzero(&vv, (size_t)sizeof (vv));
        vv.vfs_mountp = mountp;
        return (getvfsany(fd, vp, &vv));
}

int
getvfsany(FILE *fd, struct vfstab *vgetp, struct vfstab *vrefp)
{
        int     ret, bstat, cstat;
        mode_t  bmode, cmode;
        dev_t   brdev, crdev;
        struct stat64   statb;
        off64_t start = ftello64(fd);

        /* Match by straight strcmp */
        while ((ret = getvfsent(fd, vgetp)) == 0 &&
            (DIFF(vfs_special) || DIFF(vfs_fsckdev) ||
            DIFF(vfs_mountp) ||
            DIFF(vfs_fstype) ||
            DIFF(vfs_fsckpass) ||
            DIFF(vfs_automnt) ||
            DIFF(vfs_mntopts)))
                ;

        /* If something other than EOF, return it */
        if (ret != -1)
                return (ret);

        /*
         * Go back to the original location in the file and try to
         * match the devices by doing stat's (retains compatibility
         * with original getvfsany).
         */
        (void) fseeko64(fd, start, SEEK_SET);

        if (vrefp->vfs_special && stat64(vrefp->vfs_special, &statb) == 0 &&
            ((bmode = (statb.st_mode & S_IFMT)) == S_IFBLK ||
            bmode == S_IFCHR)) {
                bstat = 1;
                brdev = statb.st_rdev;
        } else
                bstat = 0;

        if (vrefp->vfs_fsckdev && stat64(vrefp->vfs_fsckdev, &statb) == 0 &&
            ((cmode = (statb.st_mode & S_IFMT)) == S_IFBLK ||
            cmode == S_IFCHR)) {
                cstat = 1;
                crdev = statb.st_rdev;
        } else
                cstat = 0;

        while ((ret = getvfsent(fd, vgetp)) == 0 &&
            ((bstat == 0 && DIFF(vfs_special)) ||
            (bstat == 1 && SDIFF(vfs_special, bmode, brdev)) ||
            (cstat == 0 && DIFF(vfs_fsckdev)) ||
            (cstat == 1 && SDIFF(vfs_fsckdev, cmode, crdev)) ||
            DIFF(vfs_mountp) ||
            DIFF(vfs_fstype) ||
            DIFF(vfs_fsckpass) ||
            DIFF(vfs_automnt) ||
            DIFF(vfs_mntopts)))
                ;
        return (ret);
}

int
getvfsent(FILE *fd, struct vfstab *vp)
{
        int     ret;
        char    *tmp, *line;

        line = tsdalloc(_T_GETVFSENT, VFS_LINE_MAX, NULL);
        if (line == NULL)
                return (0);

        /* skip leading spaces and comments */
        if ((ret = getaline(line, fd)) != 0)
                return (ret);

        /* split up each field */
        GETTOK_R(vfs_special, line, &tmp);
        GETTOK_R(vfs_fsckdev, NULL, &tmp);
        GETTOK_R(vfs_mountp, NULL, &tmp);
        GETTOK_R(vfs_fstype, NULL, &tmp);
        GETTOK_R(vfs_fsckpass, NULL, &tmp);
        GETTOK_R(vfs_automnt, NULL, &tmp);
        GETTOK_R(vfs_mntopts, NULL, &tmp);

        /* check for too many fields */
        if (strtok_r(NULL, sepstr, &tmp) != NULL)
                return (VFS_TOOMANY);

        return (0);
}

static int
getaline(char *lp, FILE *fd)
{
        char    *cp;

        while ((lp = fgets(lp, VFS_LINE_MAX, fd)) != NULL) {
                if (strlen(lp) == VFS_LINE_MAX-1 && lp[VFS_LINE_MAX-2] != '\n')
                        return (VFS_TOOLONG);

                for (cp = lp; *cp == ' ' || *cp == '\t'; cp++)
                        ;

                if (*cp != '#' && *cp != '\n')
                        return (0);
        }
        return (-1);
}