/*-
 * Copyright (c) 1980, 1988, 1991, 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.
 *
 * @(#)traverse.c       8.7 (Berkeley) 6/15/95
 * $FreeBSD: src/sbin/dump/traverse.c,v 1.10.2.6 2003/04/14 20:10:35 johan Exp $
 */

#include <sys/param.h>
#include <sys/stat.h>
#include <vfs/ufs/dir.h>
#include <vfs/ufs/dinode.h>
#include <vfs/ufs/fs.h>

#include <protocols/dumprestore.h>

#include <ctype.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>

#include "dump.h"

#define HASDUMPEDFILE   0x1
#define HASSUBDIRS      0x2

#ifdef  FS_44INODEFMT
typedef quad_t fsizeT;
#else
typedef long fsizeT;
#endif

static int      dirindir(ufs1_ino_t, daddr_t, int, long *, long *, int);
static void     dmpindir(ufs1_ino_t, daddr_t, int, fsizeT *);
static  int searchdir(ufs1_ino_t, daddr_t, long, long, long *, int);

/*
 * This is an estimation of the number of TP_BSIZE blocks in the file.
 * It estimates the number of blocks in files with holes by assuming
 * that all of the blocks accounted for by di_blocks are data blocks
 * (when some of the blocks are usually used for indirect pointers);
 * hence the estimate may be high.
 */
long
blockest(struct ufs1_dinode *dp)
{
        long blkest, sizeest;

        /*
         * dp->di_size is the size of the file in bytes.
         * dp->di_blocks stores the number of sectors actually in the file.
         * If there are more sectors than the size would indicate, this just
         *      means that there are indirect blocks in the file or unused
         *      sectors in the last file block; we can safely ignore these
         *      (blkest = sizeest below).
         * If the file is bigger than the number of sectors would indicate,
         *      then the file has holes in it.  In this case we must use the
         *      block count to estimate the number of data blocks used, but
         *      we use the actual size for estimating the number of indirect
         *      dump blocks (sizeest vs. blkest in the indirect block
         *      calculation).
         */
        blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
        sizeest = howmany(dp->di_size, TP_BSIZE);
        if (blkest > sizeest)
                blkest = sizeest;
        if (dp->di_size > (unsigned)sblock->fs_bsize * UFS_NDADDR) {
                /* calculate the number of indirect blocks on the dump tape */
                blkest +=
                        howmany(sizeest - UFS_NDADDR * sblock->fs_bsize / TP_BSIZE,
                        TP_NINDIR);
        }
        return (blkest + 1);
}

/* Auxiliary macro to pick up files changed since previous dump. */
#define CHANGEDSINCE(dp, t) \
        ((dp)->di_mtime >= (t) || (dp)->di_ctime >= (t))

/* The WANTTODUMP macro decides whether a file should be dumped. */
#ifdef UF_NODUMP
#define WANTTODUMP(dp) \
        (CHANGEDSINCE(dp, spcl.c_ddate) && \
         (nonodump || ((dp)->di_flags & UF_NODUMP) != UF_NODUMP))
#else
#define WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
#endif

/*
 * Dump pass 1.
 *
 * Walk the inode list for a filesystem to find all allocated inodes
 * that have been modified since the previous dump time. Also, find all
 * the directories in the filesystem.
 */
int
mapfiles(ufs1_ino_t maxino, long *tape_size)
{
        int mode;
        ufs1_ino_t ino;
        struct ufs1_dinode *dp;
        int anydirskipped = 0;

        for (ino = UFS_ROOTINO; ino < maxino; ino++) {
                dp = getino(ino);
                if ((mode = (dp->di_mode & IFMT)) == 0)
                        continue;
                /*
                 * Everything must go in usedinomap so that a check
                 * for "in dumpdirmap but not in usedinomap" to detect
                 * dirs with nodump set has a chance of succeeding
                 * (this is used in mapdirs()).
                 */
                SETINO(ino, usedinomap);
                if (mode == IFDIR)
                        SETINO(ino, dumpdirmap);
                if (WANTTODUMP(dp)) {
                        SETINO(ino, dumpinomap);
                        if (mode != IFREG && mode != IFDIR && mode != IFLNK)
                                *tape_size += 1;
                        else
                                *tape_size += blockest(dp);
                        continue;
                }
                if (mode == IFDIR) {
                        if (!nonodump && (dp->di_flags & UF_NODUMP))
                                CLRINO(ino, usedinomap);
                        anydirskipped = 1;
                }
        }
        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(UFS_ROOTINO, dumpinomap);
        return (anydirskipped);
}

/*
 * Dump pass 2.
 *
 * Scan each directory on the filesystem to see if it has any modified
 * files in it. If it does, and has not already been added to the dump
 * list (because it was itself modified), then add it. If a directory
 * has not been modified itself, contains no modified files and has no
 * subdirectories, then it can be deleted from the dump list and from
 * the list of directories. By deleting it from the list of directories,
 * its parent may now qualify for the same treatment on this or a later
 * pass using this algorithm.
 */
int
mapdirs(ufs1_ino_t maxino, long *tape_size)
{
        struct  ufs1_dinode *dp;
        int isdir, nodump;
        unsigned int i;
        char *map;
        ufs1_ino_t ino;
        struct ufs1_dinode di;
        long filesize;
        int ret, change = 0;

        isdir = 0;              /* XXX just to get gcc to shut up */
        for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
                if (((ino - 1) % NBBY) == 0)    /* map is offset by 1 */
                        isdir = *map++;
                else
                        isdir >>= 1;
                /*
                 * If a directory has been removed from usedinomap, it
                 * either has the nodump flag set, or has inherited
                 * it.  Although a directory can't be in dumpinomap if
                 * it isn't in usedinomap, we have to go through it to
                 * propagate the nodump flag.
                 */
                nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
                if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
                        continue;
                dp = getino(ino);
                di = *dp;       /* inode buf may change in searchdir(). */
                filesize = di.di_size;
                for (ret = 0, i = 0; filesize > 0 && i < UFS_NDADDR; i++) {
                        if (di.di_db[i] != 0) {
                                ret |= searchdir(ino, di.di_db[i],
                                        (long)dblksize(sblock, &di, i),
                                        filesize, tape_size, nodump);
                        }
                        if (ret & HASDUMPEDFILE)
                                filesize = 0;
                        else
                                filesize -= sblock->fs_bsize;
                }
                for (i = 0; filesize > 0 && i < UFS_NIADDR; i++) {
                        if (di.di_ib[i] == 0)
                                continue;
                        ret |= dirindir(ino, di.di_ib[i], i, &filesize,
                            tape_size, nodump);
                }
                if (ret & HASDUMPEDFILE) {
                        SETINO(ino, dumpinomap);
                        *tape_size += blockest(&di);
                        change = 1;
                        continue;
                }
                if (nodump) {
                        if (ret & HASSUBDIRS)
                                change = 1;     /* subdirs inherit nodump */
                        CLRINO(ino, dumpdirmap);
                } else if ((ret & HASSUBDIRS) == 0)
                        if (!TSTINO(ino, dumpinomap)) {
                                CLRINO(ino, dumpdirmap);
                                change = 1;
                        }
        }
        return (change);
}

/*
 * Read indirect blocks, and pass the data blocks to be searched
 * as directories. Quit as soon as any entry is found that will
 * require the directory to be dumped.
 */
static int
dirindir(ufs1_ino_t ino, daddr_t blkno, int ind_level, long *filesize,
         long *tape_size, int nodump)
{
        int ret = 0;
        int i;
        daddr_t idblk[MAXNINDIR];

        bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
        if (ind_level <= 0) {
                for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
                        blkno = idblk[i];
                        if (blkno != 0) {
                                ret |= searchdir(ino, blkno, sblock->fs_bsize,
                                        *filesize, tape_size, nodump);
                        }
                        if (ret & HASDUMPEDFILE)
                                *filesize = 0;
                        else
                                *filesize -= sblock->fs_bsize;
                }
                return (ret);
        }
        ind_level--;
        for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
                blkno = idblk[i];
                if (blkno != 0) {
                        ret |= dirindir(ino, blkno, ind_level, filesize,
                            tape_size, nodump);
                }
        }
        return (ret);
}

/*
 * Scan a disk block containing directory information looking to see if
 * any of the entries are on the dump list and to see if the directory
 * contains any subdirectories.
 */
static int
searchdir(ufs1_ino_t ino, daddr_t blkno, long size, long filesize,
          long *tape_size, int nodump)
{
        struct direct *dp;
        struct ufs1_dinode *ip;
        long loc, ret = 0;
        char dblk[MAXBSIZE];

        bread(fsbtodb(sblock, blkno), dblk, (int)size);
        if (filesize < size)
                size = filesize;
        for (loc = 0; loc < size; ) {
                dp = (struct direct *)(dblk + loc);
                if (dp->d_reclen == 0) {
                        msg("corrupted directory, inumber %d\n", ino);
                        break;
                }
                loc += dp->d_reclen;
                if (dp->d_ino == 0)
                        continue;
                if (dp->d_name[0] == '.') {
                        if (dp->d_name[1] == '\0')
                                continue;
                        if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
                                continue;
                }
                if (nodump) {
                        ip = getino(dp->d_ino);
                        if (TSTINO(dp->d_ino, dumpinomap)) {
                                CLRINO(dp->d_ino, dumpinomap);
                                *tape_size -= blockest(ip);
                        }
                        /*
                         * Add back to dumpdirmap and remove from usedinomap
                         * to propagate nodump.
                         */
                        if ((ip->di_mode & IFMT) == IFDIR) {
                                SETINO(dp->d_ino, dumpdirmap);
                                CLRINO(dp->d_ino, usedinomap);
                                ret |= HASSUBDIRS;
                        }
                } else {
                        if (TSTINO(dp->d_ino, dumpinomap)) {
                                ret |= HASDUMPEDFILE;
                                if (ret & HASSUBDIRS)
                                        break;
                        }
                        if (TSTINO(dp->d_ino, dumpdirmap)) {
                                ret |= HASSUBDIRS;
                                if (ret & HASDUMPEDFILE)
                                        break;
                        }
                }
        }
        return (ret);
}

/*
 * Dump passes 3 and 4.
 *
 * Dump the contents of an inode to tape.
 */
void
dumpino(struct ufs1_dinode *dp, ufs1_ino_t ino)
{
        int ind_level, cnt;
        fsizeT size;
        char buf[TP_BSIZE];

        if (newtape) {
                newtape = 0;
                dumpmap(dumpinomap, TS_BITS, ino);
        }
        CLRINO(ino, dumpinomap);
        spcl.c_dinode = *dp;
        spcl.c_type = TS_INODE;
        spcl.c_count = 0;
        switch (dp->di_mode & S_IFMT) {

        case 0:
                /*
                 * Freed inode.
                 */
                return;

        case S_IFLNK:
                /*
                 * Check for short symbolic link.
                 */
#ifdef FS_44INODEFMT
                if (dp->di_size > 0 &&
                    dp->di_size < (unsigned)sblock->fs_maxsymlinklen) {
                        spcl.c_addr[0] = 1;
                        spcl.c_count = 1;
                        writeheader(ino);
                        memmove(buf, dp->di_shortlink, (u_long)dp->di_size);
                        buf[dp->di_size] = '\0';
                        writerec(buf, 0);
                        return;
                }
#endif
                /* fall through */

        case S_IFDIR:
        case S_IFREG:
                if (dp->di_size > 0)
                        break;
                /* fall through */

        case S_IFIFO:
        case S_IFSOCK:
        case S_IFCHR:
        case S_IFBLK:
                writeheader(ino);
                return;

        default:
                msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
                return;
        }
        if (dp->di_size > UFS_NDADDR * (unsigned)sblock->fs_bsize)
                cnt = UFS_NDADDR * sblock->fs_frag;
        else
                cnt = howmany(dp->di_size, sblock->fs_fsize);
        blksout(&dp->di_db[0], cnt, ino);
        if ((size = dp->di_size - UFS_NDADDR * sblock->fs_bsize) <= 0)
                return;
        for (ind_level = 0; ind_level < UFS_NIADDR; ind_level++) {
                dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
                if (size <= 0)
                        return;
        }
}

/*
 * Read indirect blocks, and pass the data blocks to be dumped.
 */
static void
dmpindir(ufs1_ino_t ino, daddr_t blk, int ind_level, fsizeT *size)
{
        int i, cnt;
        daddr_t idblk[MAXNINDIR];

        if (blk != 0)
                bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
        else
                memset(idblk, 0, (int)sblock->fs_bsize);
        if (ind_level <= 0) {
                if (*size < NINDIR(sblock) * sblock->fs_bsize)
                        cnt = howmany(*size, sblock->fs_fsize);
                else
                        cnt = NINDIR(sblock) * sblock->fs_frag;
                *size -= NINDIR(sblock) * sblock->fs_bsize;
                blksout(&idblk[0], cnt, ino);
                return;
        }
        ind_level--;
        for (i = 0; i < NINDIR(sblock); i++) {
                dmpindir(ino, idblk[i], ind_level, size);
                if (*size <= 0)
                        return;
        }
}

/*
 * Collect up the data into tape record sized buffers and output them.
 */
void
blksout(daddr_t *blkp, int frags, ufs1_ino_t ino)
{
        daddr_t *bp;
        int i, j, count, blks, tbperdb;

        blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
        tbperdb = sblock->fs_bsize >> tp_bshift;
        for (i = 0; i < blks; i += TP_NINDIR) {
                if (i + TP_NINDIR > blks)
                        count = blks;
                else
                        count = i + TP_NINDIR;
                for (j = i; j < count; j++)
                        if (blkp[j / tbperdb] != 0)
                                spcl.c_addr[j - i] = 1;
                        else
                                spcl.c_addr[j - i] = 0;
                spcl.c_count = count - i;
                writeheader(ino);
                bp = &blkp[i / tbperdb];
                for (j = i; j < count; j += tbperdb, bp++)
                        if (*bp != 0) {
                                if (j + tbperdb <= count)
                                        dumpblock(*bp, (int)sblock->fs_bsize);
                                else
                                        dumpblock(*bp, (count - j) * TP_BSIZE);
                        }
                spcl.c_type = TS_ADDR;
        }
}

/*
 * Dump a map to the tape.
 */
void
dumpmap(const char *map, int type, ufs1_ino_t ino)
{
        int i;
        const char *cp;

        spcl.c_type = type;
        spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
        writeheader(ino);
        for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
                writerec(cp, 0);
}

/*
 * Write a header record to the dump tape.
 */
void
writeheader(ufs1_ino_t ino)
{
        int32_t sum, cnt, *lp;

        spcl.c_inumber = ino;
        spcl.c_magic = NFS_MAGIC;
        spcl.c_checksum = 0;
        lp = (int32_t *)&spcl;
        sum = 0;
        cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
        while (--cnt >= 0) {
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
        }
        spcl.c_checksum = CHECKSUM - sum;
        writerec(&spcl, 1);
}

struct ufs1_dinode *
getino(ufs1_ino_t inum)
{
        static daddr_t minino, maxino;
        static struct ufs1_dinode inoblock[MAXINOPB];

        curino = inum;
        if (inum >= (unsigned)minino && inum < (unsigned)maxino)
                return (&inoblock[inum - minino]);
        bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), (char *)inoblock,
            (int)sblock->fs_bsize);
        minino = inum - (inum % INOPB(sblock));
        maxino = minino + INOPB(sblock);
        return (&inoblock[inum - minino]);
}

/*
 * Read a chunk of data from the disk.
 * Try to recover from hard errors by reading in sector sized pieces.
 * Error recovery is attempted at most BREADEMAX times before seeking
 * consent from the operator to continue.
 */
int     breaderrors = 0;
#define BREADEMAX 32

void
bread(daddr_t blkno, char *buf, int size)
{
        int cnt, i;

loop:
        cnt = cread(diskfd, buf, size, ((off_t)blkno << dev_bshift));
        if (cnt == size)
                return;
        if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
                /*
                 * Trying to read the final fragment.
                 *
                 * NB - dump only works in TP_BSIZE blocks, hence
                 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
                 * It should be smarter about not actually trying to
                 * read more than it can get, but for the time being
                 * we punt and scale back the read only when it gets
                 * us into trouble. (mkm 9/25/83)
                 */
                size -= dev_bsize;
                goto loop;
        }
        if (cnt == -1)
                msg("read error from %s: %s: [block %d]: count=%d\n",
                        disk, strerror(errno), blkno, size);
        else
                msg("short read error from %s: [block %d]: count=%d, got=%d\n",
                        disk, blkno, size, cnt);
        if (++breaderrors > BREADEMAX) {
                msg("More than %d block read errors from %s\n",
                        BREADEMAX, disk);
                broadcast("DUMP IS AILING!\n");
                msg("This is an unrecoverable error.\n");
                if (!query("Do you want to attempt to continue?")){
                        dumpabort(0);
                        /*NOTREACHED*/
                } else
                        breaderrors = 0;
        }
        /*
         * Zero buffer, then try to read each sector of buffer separately,
         * and bypass the cache.
         */
        memset(buf, 0, size);
        for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
                if ((cnt = pread(diskfd, buf, (int)dev_bsize,
                    ((off_t)blkno << dev_bshift))) == dev_bsize)
                        continue;
                if (cnt == -1) {
                        msg("read error from %s: %s: [sector %d]: count=%ld\n",
                                disk, strerror(errno), blkno, dev_bsize);
                        continue;
                }
                msg("short read error from %s: [sector %d]: count=%ld, got=%d\n",
                        disk, blkno, dev_bsize, cnt);
        }
}