A wrong line in /etc/fstab containing LABEL=... could prevent dump from running....

[dump.git] / dump / optr.c

/*
 *      Ported to Linux's Second Extended File System as part of the
 *      dump and restore backup suit
 *      Remy Card <card@Linux.EU.Org>, 1994-1997
 *      Stelian Pop <stelian@popies.net>, 1999-2000
 *      Stelian Pop <stelian@popies.net> - Alcôve <www.alcove.com>, 2000-2002
 */

/*-
 * Copyright (c) 1980, 1988, 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.
 */

#ifndef lint
static const char rcsid[] =
        "$Id: optr.c,v 1.39 2004/07/05 15:12:45 stelian Exp $";
#endif /* not lint */

#include <config.h>
#include <sys/param.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <time.h>

#include <errno.h>
#include <mntent.h>
#include <paths.h>
#include <grp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <utmp.h>
#include <sys/stat.h>

#ifdef __linux__
#ifdef HAVE_EXT2FS_EXT2_FS_H
#include <ext2fs/ext2_fs.h>
#else
#include <linux/ext2_fs.h>
#endif
#include <ext2fs/ext2fs.h>
#include <bsdcompat.h>
#include <signal.h>
#endif

#include "dump.h"
#include "pathnames.h"
#include "bylabel.h"

static  void alarmcatch __P((int));
int     datesort __P((const void *, const void *));
static  void sendmes __P((const char *, const char *));

/* List of filesystem types that we can dump (same ext2 on-disk format) */
static char *fstypes[] = { "ext2", "ext3", "InterMezzo", NULL };

/*
 *      Query the operator; This previously-fascist piece of code
 *      no longer requires an exact response.
 *      It is intended to protect dump aborting by inquisitive
 *      people banging on the console terminal to see what is
 *      happening which might cause dump to croak, destroying
 *      a large number of hours of work.
 *
 *      Every 2 minutes we reprint the message, alerting others
 *      that dump needs attention.
 */
static  int timeout;
static  const char *attnmessage;                /* attention message */

int
query(const char *question)
{
        char    replybuffer[64];
        int     back, errcount;
        FILE    *mytty;
        time_t  firstprompt, when_answered;

        if (qflag) {
                msg("%s - forced abort\n", question);
                dumpabort(0);
                /* NOTREACHED */
        }

        firstprompt = time(NULL);

        if ((mytty = fopen(_PATH_TTY, "r")) == NULL)
                quit("fopen on %s fails: %s\n", _PATH_TTY, strerror(errno));
        attnmessage = question;
        timeout = 0;
        alarmcatch(0);
        back = -1;
        errcount = 0;
        do {
                if (fgets(replybuffer, 63, mytty) == NULL) {
                        clearerr(mytty);
                        if (++errcount > 30)    /* XXX  ugly */
                                quit("excessive operator query failures\n");
                } else if (replybuffer[0] == 'y' || replybuffer[0] == 'Y') {
                        back = 1;
                } else if (replybuffer[0] == 'n' || replybuffer[0] == 'N') {
                        back = 0;
                } else {
                        (void) fprintf(stderr,
                            "  DUMP: \"Yes\" or \"No\"?\n");
                        (void) fprintf(stderr,
                            "  DUMP: %s: (\"yes\" or \"no\") ", question);
                }
        } while (back < 0);

        /*
         *      Turn off the alarm, and reset the signal to trap out..
         */
        (void) alarm(0);
        if (signal(SIGALRM, sig) == SIG_IGN)
                signal(SIGALRM, SIG_IGN);
        (void) fclose(mytty);
        when_answered = time(NULL);
        /*
         * Adjust the base for time estimates to ignore time we spent waiting
         * for operator input.
         */
        if (tstart_writing != 0)
                tstart_writing += (when_answered - firstprompt);
        return(back);
}

char lastmsg[BUFSIZ];

/*
 *      Alert the console operator, and enable the alarm clock to
 *      sleep for 2 minutes in case nobody comes to satisfy dump
 */
static void
alarmcatch(UNUSED(int signo))
{
        int save_errno = errno;
        if (notify == 0) {
                if (timeout == 0)
                        (void) fprintf(stderr,
                            "  DUMP: %s: (\"yes\" or \"no\") ",
                            attnmessage);
                else
                        msgtail("\7\7");
        } else {
                if (timeout) {
                        msgtail("\n");
                        broadcast("");          /* just print last msg */
                }
                (void) fprintf(stderr,"  DUMP: %s: (\"yes\" or \"no\") ",
                    attnmessage);
        }
        signal(SIGALRM, alarmcatch);
        (void) alarm(120);
        timeout = 1;
        errno = save_errno;
}

/*
 *      Here if an inquisitive operator interrupts the dump program
 */
void
interrupt(UNUSED(int signo))
{
        msg("Interrupt received.\n");
        if (query("Do you want to abort dump?"))
                dumpabort(0);
}

/*
 *      The following variables and routines manage alerting
 *      operators to the status of dump.
 *      This works much like wall(1) does.
 */
struct  group *gp;

/*
 *      Get the names from the group entry "operator" to notify.
 */
void
set_operators(void)
{
        if (!notify)            /*not going to notify*/
                return;
        gp = getgrnam(OPGRENT);
        (void) endgrent();
        if (gp == NULL) {
                msg("No group entry for %s.\n", OPGRENT);
                notify = 0;
                return;
        }
}

struct tm *localclock;

/*
 *      We fork a child to do the actual broadcasting, so
 *      that the process control groups are not messed up
 */
void
broadcast(const char *message)
{
        time_t          clock;
        FILE    *f_utmp;
        struct  utmp    utmp;
        char    **np;
        int     pid, s;

        if (!notify || gp == NULL)
                return;

        switch (pid = fork()) {
        case -1:
                return;
        case 0:
                break;
        default:
                while (wait(&s) != pid)
                        continue;
                return;
        }

        clock = time(NULL);
        localclock = localtime(&clock);

        if ((f_utmp = fopen(_PATH_UTMP, "r")) == NULL) {
                msg("Cannot open %s: %s\n", _PATH_UTMP, strerror(errno));
                return;
        }

        while (!feof(f_utmp)) {
                if (fread((char *) &utmp, sizeof (struct utmp), 1, f_utmp) != 1)
                        break;
                if (utmp.ut_name[0] == 0)
                        continue;
                for (np = gp->gr_mem; *np; np++) {
                        if (strncmp(*np, utmp.ut_name, sizeof(utmp.ut_name)) != 0)
                                continue;
                        /*
                         *      Do not send messages to operators on dialups
                         */
                        if (strncmp(utmp.ut_line, DIALUP, strlen(DIALUP)) == 0)
                                continue;
#ifdef DEBUG
                        msg("Message to %s at %s\n", *np, utmp.ut_line);
#endif
                        sendmes(utmp.ut_line, message);
                }
        }
        (void) fclose(f_utmp);
        Exit(0);        /* the wait in this same routine will catch this */
        /* NOTREACHED */
}

static void
sendmes(const char *tty, const char *message)
{
        char t[MAXPATHLEN], buf[BUFSIZ];
        const char *cp;
        int lmsg = 1;
        FILE *f_tty;

        (void) strcpy(t, _PATH_DEV);
        (void) strncat(t, tty, sizeof t - strlen(_PATH_DEV) - 1);

        if ((f_tty = fopen(t, "w")) != NULL) {
                setbuf(f_tty, buf);
                (void) fprintf(f_tty,
                    "\n\
\7\7\7Message from the dump program to all operators at %d:%02d ...\r\n\n\
DUMP: NEEDS ATTENTION: ",
                    localclock->tm_hour, localclock->tm_min);
                for (cp = lastmsg; ; cp++) {
                        if (*cp == '\0') {
                                if (lmsg) {
                                        cp = message;
                                        if (!(cp && *cp != '\0'))
                                                break;
                                        lmsg = 0;
                                } else
                                        break;
                        }
                        if (*cp == '\n')
                                (void) putc('\r', f_tty);
                        (void) putc(*cp, f_tty);
                }
                (void) fclose(f_tty);
        }
}

/*
 *      print out an estimate of the amount of time left to do the dump
 */

time_t  tschedule = 0;

void
timeest(void)
{
        time_t tnow = time(NULL);

        if (tnow >= tschedule) {
                char *buf = mktimeest(tnow);
                tschedule = tnow + 300;
                if (buf) {
                        fprintf(stderr, "  DUMP: ");
                        fwrite(buf, strlen(buf), 1, stderr);
                        fflush(stderr);
                }
        }
}

void
#ifdef __STDC__
msg(const char *fmt, ...)
#else
msg(fmt, va_alist)
        char *fmt;
        va_dcl
#endif
{
        va_list ap;

        (void) fprintf(stderr,"  DUMP: ");
#ifdef TDEBUG
        (void) fprintf(stderr, "pid=%d ", getpid());
#endif
#ifdef __STDC__
        va_start(ap, fmt);
#else
        va_start(ap);
#endif
        (void) vfprintf(stderr, fmt, ap);
        va_end(ap);
        (void) fflush(stdout);
        (void) fflush(stderr);
#ifdef __STDC__
        va_start(ap, fmt);
#else
        va_start(ap);
#endif
        (void) vsnprintf(lastmsg, sizeof(lastmsg), fmt, ap);
        va_end(ap);
}

void
#ifdef __STDC__
msgtail(const char *fmt, ...)
#else
msgtail(fmt, va_alist)
        char *fmt;
        va_dcl
#endif
{
        va_list ap;
#ifdef __STDC__
        va_start(ap, fmt);
#else
        va_start(ap);
#endif
        (void) vfprintf(stderr, fmt, ap);
        va_end(ap);
}

void
#ifdef __STDC__
quit(const char *fmt, ...)
#else
quit(fmt, va_alist)
        char *fmt;
        va_dcl
#endif
{
        va_list ap;

        (void) fprintf(stderr,"  DUMP: ");
#ifdef TDEBUG
        (void) fprintf(stderr, "pid=%d ", getpid());
#endif
#ifdef __STDC__
        va_start(ap, fmt);
#else
        va_start(ap);
#endif
        (void) vfprintf(stderr, fmt, ap);
        va_end(ap);
        (void) fflush(stdout);
        (void) fflush(stderr);
        dumpabort(0);
}

/*
 *      Tell the operator what has to be done;
 *      we don't actually do it
 */

struct  pfstab {
        struct  pfstab *pf_next;
        struct  dumpdates *pf_dd;
        struct  mntent *pf_mntent;
};

static  struct pfstab *table;

static struct mntent *
allocfsent(struct mntent *fs)
{
        struct mntent *new;
        const char *disk;
        struct stat buf, tabbuf;
        struct pfstab *tabpf;
        struct mntent *tabfs;

        new = (struct mntent *)malloc(sizeof (*fs));
        if (new == NULL)
                quit("%s\n", strerror(errno));

        /* Translade UUID=, LABEL= ... */
        disk = get_device_name(fs->mnt_fsname);
        if (disk == NULL)
                disk = strdup(fs->mnt_fsname);

        /* Discard non block devices */
        if (stat(disk, &buf) != 0 || !S_ISBLK(buf.st_mode)) {
                free(new);
                return NULL;
        }

        /* Discard same major/minor devices */
        for (tabpf = table; tabpf != NULL; tabpf = tabpf->pf_next) {
                tabfs = tabpf->pf_mntent;
                if (stat(tabfs->mnt_fsname, &tabbuf) != 0)
                        /* should not happen */
                        quit("Cannot access %s\n", tabfs->mnt_fsname);
                if (tabbuf.st_rdev == buf.st_rdev) {
                        free(new);
                        /* Copy passno and freq from /etc/fstab because 
                         * /etc/mtab does always have them as 0 0 */
                        if (!tabfs->mnt_passno)
                                tabfs->mnt_passno = fs->mnt_passno;
                        if (!tabfs->mnt_freq)
                                tabfs->mnt_freq = fs->mnt_freq;
                        return NULL;
                }
        }
                
        if (strlen(fs->mnt_dir) > 1 && fs->mnt_dir[strlen(fs->mnt_dir) - 1] == '/')
                fs->mnt_dir[strlen(fs->mnt_dir) - 1] = '\0';
        if ((new->mnt_dir = strdup(fs->mnt_dir)) == NULL ||
            (new->mnt_type = strdup(fs->mnt_type)) == NULL ||
            (new->mnt_opts = strdup(fs->mnt_opts)) == NULL ||
            (new->mnt_fsname = strdup(disk)) == NULL)
                quit("%s\n", strerror(errno));
        new->mnt_passno = fs->mnt_passno;
        new->mnt_freq = fs->mnt_freq;
        return (new);
}

void
getfstab(void)
{
        struct mntent *fs;
        struct pfstab *pf;
        struct pfstab *pfold = NULL;
        FILE *mntfp;
        char *mnttables[] = { _PATH_MOUNTED, _PATH_MNTTAB, 0 };
        int i;

        for (i = 0; mnttables[i]; i++) {
                mntfp = setmntent(mnttables[i], "r");
                if (mntfp == NULL) {
                        msg("Can't open %s for dump table information: %s\n",
                            mnttables[i], strerror(errno));
                        continue;
                }
                while ((fs = getmntent(mntfp)) != NULL) {
                        fs = allocfsent(fs);
                        if (!fs)
                                continue;
                        fs->mnt_passno = 0;
                        if ((pf = (struct pfstab *)malloc(sizeof (*pf))) == NULL)
                                quit("%s\n", strerror(errno));
                        pf->pf_mntent = fs;
                        pf->pf_next = NULL;
        
                        /* keep table in /etc/fstab order for use with -w and -W */
                        if (pfold) {
                                pfold->pf_next = pf;
                                pfold = pf;
                        } else
                                pfold = table = pf;
                }
                (void) endmntent(mntfp);
        }
}

/*
 * Search in the fstab for a file name.
 * This file name can be either the special or the path file name.
 *
 * The entries in the fstab are the BLOCK special names, not the
 * character special names.
 * The caller of fstabsearch assures that the character device
 * is dumped (that is much faster)
 *
 * The file name can omit the leading '/'.
 */
struct mntent *
fstabsearch(const char *key)
{
        struct pfstab *pf;
        struct mntent *fs;
        const char *rn;

        for (pf = table; pf != NULL; pf = pf->pf_next) {
                fs = pf->pf_mntent;
                if (strcmp(fs->mnt_dir, key) == 0 ||
                    strcmp(fs->mnt_fsname, key) == 0)
                        return (fs);
                rn = rawname(fs->mnt_fsname);
                if (rn != NULL && strcmp(rn, key) == 0)
                        return (fs);
                if (key[0] != '/') {
                        if (*fs->mnt_fsname == '/' &&
                            strcmp(fs->mnt_fsname + 1, key) == 0)
                                return (fs);
                        if (*fs->mnt_dir == '/' &&
                            strcmp(fs->mnt_dir + 1, key) == 0)
                                return (fs);
                }
        }
        return (NULL);
}

#ifdef  __linux__
struct mntent *
fstabsearchdir(const char *key, char *directory)
{
        struct pfstab *pf;
        struct mntent *fs;
        struct mntent *found_fs = NULL;
        unsigned int size = 0;
        struct stat buf;

        if (stat(key, &buf) == 0 && S_ISBLK(buf.st_mode))
                return NULL;

        for (pf = table; pf != NULL; pf = pf->pf_next) {
                fs = pf->pf_mntent;
                if (strlen(fs->mnt_dir) > size &&
                    strlen(key) > strlen(fs->mnt_dir) &&
                    strncmp(fs->mnt_dir, key, strlen(fs->mnt_dir)) == 0 &&
                    (key[strlen(fs->mnt_dir)] == '/' ||
                     fs->mnt_dir[strlen(fs->mnt_dir) - 1] == '/')) {
                        found_fs = fs;
                        size = strlen(fs->mnt_dir);
                }
        }
        if (found_fs != NULL) {
                /*
                 * Ok, we have found a fstab entry which matches the argument
                 * We have to split the argument name into:
                 * - a device name (from the fstab entry)
                 * - a directory name on this device
                 */
                strcpy(directory, key + size);
        }
        return(found_fs);
}
#endif

static void
print_wmsg(char arg, int dumpme, const char *dev, int level,
           const char *mtpt, time_t ddate)
{
#ifdef FDEBUG
        printf("checking dev %s: lvl %d, mtpt %s\n", dev, level, mtpt);
#endif
        if (!dumpme && arg == 'w')
                return;

        (void) printf("%c %8s\t(%6s) Last dump: ",
                      dumpme && (arg != 'w') ? '>' : ' ',
                      dev,
                      mtpt ? mtpt : "");

        /*
         * Check ddate > 365 to avoid issues with fs in stab but not dumpdates.
         * Not a problem, because ddate is in seconds since the epoch anyways.
         */
        if (ddate > 365) {
                char *date, *d;

                date = (char *)ctime(&ddate);
                d = strchr(date, '\n');
                if (d) *d = '\0';
                printf("Level %d, Date %s\n", level, date);
        } else
                printf("never\n");
}

/*
 *      Tell the operator what to do
 */
void
lastdump(char arg) /* w ==> just what to do; W ==> most recent dumps */
{
        struct pfstab *pf;
        time_t tnow;

        tnow = time(NULL);
        getfstab();             /* /etc/fstab input */
        initdumptimes(0);       /* dumpdates input */
        if (ddatev == NULL && table == NULL) {
                (void) printf("No %s or %s file found\n",
                              _PATH_MNTTAB, dumpdates);
                return;
        }

        if (arg == 'w')
                (void) printf("Dump these file systems:\n");
        else
                (void) printf("Last dump(s) done (Dump '>' file systems):\n");

        /* For files in dumpdates, get the last dump level and date */
        if (ddatev != NULL) {
                struct dumpdates *dtwalk = NULL;
                int i;
                char *lastname;

                qsort((char *) ddatev, nddates, sizeof(struct dumpdates *), datesort);

                lastname = "??";
                ITITERATE(i, dtwalk) {
                        struct mntent *dt;
                        if (strncmp(lastname, dtwalk->dd_name,
                                sizeof(dtwalk->dd_name)) == 0)
                                continue;
                        lastname = dtwalk->dd_name;
                        if ((dt = dtwalk->dd_fstab) != NULL) {
                                /* Overload fs_freq as dump level and
                                 * fs_passno as date, because we can't
                                 * change struct fstab format.
                                 * A positive fs_freq means this
                                 * filesystem needs to be dumped.
                                 */
                                dt->mnt_passno = dtwalk->dd_ddate;
                                if (dt->mnt_freq > 0 && (dtwalk->dd_ddate <
                                    tnow - (dt->mnt_freq * 86400)))
                                        dt->mnt_freq = dtwalk->dd_level;
                                else
                                        dt->mnt_freq = -dtwalk->dd_level;
#ifdef FDEBUG
                                printf("%s fs_freq set to %d\n", lastname,
                                        dt->mnt_freq);
#endif
                        }
                }
        }

        /* print in /etc/fstab order only those filesystem types we can dump */
        for (pf = table; pf != NULL; pf = pf->pf_next) {
                struct mntent *dt = pf->pf_mntent;
                char **type;

                for (type = fstypes; *type != NULL; type++) {
                        if (strncmp(dt->mnt_type, *type,
                                    sizeof(dt->mnt_type)) == 0) {
                                const char *disk = get_device_name(dt->mnt_fsname);
                                print_wmsg(arg, dt->mnt_freq > 0,
                                           disk ? disk : dt->mnt_fsname,
                                           dt->mnt_freq < 0 ? -dt->mnt_freq :
                                                              dt->mnt_freq,
                                           dt->mnt_dir,
                                           dt->mnt_passno);
                        }
                }
        }

        /* print in /etc/dumpdates order if not in /etc/fstab */
        if (ddatev != NULL) {
                struct dumpdates *dtwalk = NULL;
                char *lastname;
                int i;

                lastname = "??";
                ITITERATE(i, dtwalk) {
                        if (strncmp(lastname, dtwalk->dd_name,
                                sizeof(dtwalk->dd_name)) == 0 ||
                            dtwalk->dd_fstab != NULL)
                                continue;
                        lastname = dtwalk->dd_name;
                        print_wmsg(arg, 0, dtwalk->dd_name,
                                   dtwalk->dd_level, NULL, dtwalk->dd_ddate);
                }
        }
}

int
datesort(const void *a1, const void *a2)
{
        struct dumpdates *d1 = *(struct dumpdates **)a1;
        struct dumpdates *d2 = *(struct dumpdates **)a2;
        int diff;

        diff = strncmp(d1->dd_name, d2->dd_name, sizeof(d1->dd_name));
        if (diff == 0)
                return (d2->dd_ddate - d1->dd_ddate);
        return (diff);
}