/*      $OpenBSD: preen.c,v 1.20 2015/01/16 06:39:57 deraadt Exp $      */
/*      $NetBSD: preen.c,v 1.15 1996/09/28 19:21:42 christos Exp $      */

/*
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  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. 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.
 */

#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/queue.h>

#include <fstab.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>
#include <err.h>

#include "fsutil.h"

struct partentry {
        TAILQ_ENTRY(partentry)   p_entries;
        char                    *p_devname;     /* device name */
        char                    *p_mntpt;       /* mount point */
        char                    *p_type;        /* filesystem type */
        void                    *p_auxarg;      /* auxiliary argument */
};

TAILQ_HEAD(part, partentry) badh;

struct diskentry {
        TAILQ_ENTRY(diskentry)      d_entries;
        char                       *d_name;     /* disk base name */
        TAILQ_HEAD(prt, partentry)  d_part;     /* list of partitions on disk */
        pid_t                       d_pid;      /* 0 or pid of fsck proc */
};

TAILQ_HEAD(disk, diskentry) diskh;

static int nrun = 0, ndisks = 0;

static struct diskentry *finddisk(const char *);
static void addpart(const char *, const char *, const char *, void *);
static int startdisk(struct diskentry *,
    int (*)(const char *, const char *, const char *, void *, pid_t *));
static void printpart(void);

int
checkfstab(int flags, int maxrun, void *(*docheck)(struct fstab *),
    int (*checkit)(const char *, const char *, const char *, void *, pid_t *))
{
        struct fstab *fs;
        struct diskentry *d, *nextdisk;
        struct partentry *p;
        int ret, retcode, passno, sumstatus, status, maxp;
        void *auxarg;
        char *name;
        pid_t pid;

        TAILQ_INIT(&badh);
        TAILQ_INIT(&diskh);

        sumstatus = 0;
        maxp = 2;

        for (passno = 1; passno <= maxp; passno++) {
                if (setfsent() == 0) {
                        warnx("Can't open checklist file: %s", _PATH_FSTAB);
                        return (8);
                }
                while ((fs = getfsent()) != 0) {
                        if ((auxarg = (*docheck)(fs)) == NULL)
                                continue;

                        name = blockcheck(fs->fs_spec);
                        if (flags & CHECK_DEBUG)
                                printf("pass %d, name %s\n", passno, name);
                        maxp = (fs->fs_passno > maxp) ? fs->fs_passno : maxp;

                        if ((flags & CHECK_PREEN) == 0 ||
                            (passno == 1 && fs->fs_passno == 1)) {
                                if (name == NULL) {
                                        if (flags & CHECK_PREEN)
                                                return 8;
                                        else
                                                continue;
                                }
                                sumstatus = (*checkit)(fs->fs_vfstype,
                                    name, fs->fs_file, auxarg, NULL);

                                if (sumstatus)
                                        return (sumstatus);
                        } else  {
                                if (name == NULL) {
                                        (void) fprintf(stderr,
                                            "BAD DISK NAME %s\n", fs->fs_spec);
                                        sumstatus |= 8;
                                        continue;
                                }
                                if (passno == fs->fs_passno)
                                        addpart(fs->fs_vfstype, name,
                                            fs->fs_file, auxarg);
                        }
                }
                if ((flags & CHECK_PREEN) == 0)
                        return 0;
        }

        if (flags & CHECK_DEBUG)
                printpart();

        if (flags & CHECK_PREEN) {
                if (maxrun == 0)
                        maxrun = ndisks;
                if (maxrun > ndisks)
                        maxrun = ndisks;
                nextdisk = TAILQ_FIRST(&diskh);
                for (passno = 0; passno < maxrun; ++passno) {
                        if ((ret = startdisk(nextdisk, checkit)) != 0)
                                return ret;
                        nextdisk = TAILQ_NEXT(nextdisk, d_entries);
                }

                while ((pid = wait(&status)) != -1) {
                        TAILQ_FOREACH(d, &diskh, d_entries)
                                if (d->d_pid == pid)
                                        break;

                        if (d == NULL) {
                                warnx("Unknown pid %ld", (long)pid);
                                continue;
                        }


                        if (WIFEXITED(status))
                                retcode = WEXITSTATUS(status);
                        else
                                retcode = 0;

                        p = TAILQ_FIRST(&d->d_part);

                        if (flags & (CHECK_DEBUG|CHECK_VERBOSE))
                                (void) printf("done %s: %s (%s) = %x\n",
                                    p->p_type, p->p_devname, p->p_mntpt,
                                    status);

                        if (WIFSIGNALED(status)) {
                                (void) fprintf(stderr,
                                    "%s: %s (%s): EXITED WITH SIGNAL %d\n",
                                    p->p_type, p->p_devname, p->p_mntpt,
                                    WTERMSIG(status));
                                retcode = 8;
                        }

                        TAILQ_REMOVE(&d->d_part, p, p_entries);

                        if (retcode != 0) {
                                TAILQ_INSERT_TAIL(&badh, p, p_entries);
                                sumstatus |= retcode;
                        } else {
                                free(p->p_type);
                                free(p->p_devname);
                                free(p);
                        }
                        d->d_pid = 0;
                        nrun--;

                        if (TAILQ_EMPTY(&d->d_part))
                                ndisks--;

                        if (nextdisk == NULL) {
                                if (!TAILQ_EMPTY(&d->d_part)) {
                                        if ((ret = startdisk(d, checkit)) != 0)
                                                return ret;
                                }
                        } else if (nrun < maxrun && nrun < ndisks) {
                                for ( ;; ) {
                                        nextdisk = TAILQ_NEXT(nextdisk,
                                            d_entries);
                                        if (nextdisk == NULL)
                                                nextdisk = TAILQ_FIRST(&diskh);
                                        if (!TAILQ_EMPTY(&nextdisk->d_part) &&
                                            nextdisk->d_pid == 0)
                                                break;
                                }
                                if ((ret = startdisk(nextdisk, checkit)) != 0)
                                        return ret;
                        }
                }
        }
        if (sumstatus) {
                p = TAILQ_FIRST(&badh);
                if (p == NULL)
                        return (sumstatus);

                (void) fprintf(stderr,
                        "THE FOLLOWING FILE SYSTEM%s HAD AN %s\n\t",
                        TAILQ_NEXT(p, p_entries) ? "S" : "",
                        "UNEXPECTED INCONSISTENCY:");

                for (; p; p = TAILQ_NEXT(p, p_entries))
                        (void) fprintf(stderr,
                            "%s: %s (%s)%s", p->p_type, p->p_devname,
                            p->p_mntpt, TAILQ_NEXT(p, p_entries) ? ", " : "\n");

                return sumstatus;
        }
        (void) endfsent();
        return (0);
}


static struct diskentry *
finddisk(const char *name)
{
        const char *p;
        size_t len = 0;
        struct diskentry *d;

        for (p = name + strlen(name) - 1; p >= name; --p)
                if (isdigit((unsigned char)*p)) {
                        len = p - name + 1;
                        break;
                }

        if (p < name)
                len = strlen(name);

        TAILQ_FOREACH(d, &diskh, d_entries)
                if (strncmp(d->d_name, name, len) == 0 && d->d_name[len] == 0)
                        return d;

        d = emalloc(sizeof(*d));
        d->d_name = estrdup(name);
        d->d_name[len] = '\0';
        TAILQ_INIT(&d->d_part);
        d->d_pid = 0;

        TAILQ_INSERT_TAIL(&diskh, d, d_entries);
        ndisks++;

        return d;
}


static void
printpart(void)
{
        struct diskentry *d;
        struct partentry *p;

        TAILQ_FOREACH(d, &diskh, d_entries) {
                (void) printf("disk %s: ", d->d_name);
                TAILQ_FOREACH(p, &d->d_part, p_entries)
                        (void) printf("%s ", p->p_devname);
                (void) printf("\n");
        }
}


static void
addpart(const char *type, const char *devname, const char *mntpt, void *auxarg)
{
        struct diskentry *d = finddisk(devname);
        struct partentry *p;

        TAILQ_FOREACH(p, &d->d_part, p_entries)
                if (strcmp(p->p_devname, devname) == 0) {
                        warnx("%s in fstab more than once!", devname);
                        return;
                }

        p = emalloc(sizeof(*p));
        p->p_devname = estrdup(devname);
        p->p_mntpt = estrdup(mntpt);
        p->p_type = estrdup(type);
        p->p_auxarg = auxarg;

        TAILQ_INSERT_TAIL(&d->d_part, p, p_entries);
}


static int
startdisk(struct diskentry *d,
    int (*checkit)(const char *, const char *, const char *, void *, pid_t *))
{
        struct partentry *p = TAILQ_FIRST(&d->d_part);
        int rv;

        while ((rv = (*checkit)(p->p_type, p->p_devname, p->p_mntpt,
            p->p_auxarg, &d->d_pid)) != 0 && nrun > 0)
                sleep(10);

        if (rv == 0)
                nrun++;

        return rv;
}