From Uwe Gohlke:

[dump.git] / dump / traverse.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, 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.
 */

#ifndef lint
static const char rcsid[] =
        "$Id: traverse.c,v 1.56 2003/10/26 16:05:47 stelian Exp $";
#endif /* not lint */

#include <config.h>
#include <ctype.h>
#include <stdio.h>
#include <sys/types.h>
#ifdef __STDC__
#include <string.h>
#include <unistd.h>
#endif
#include <errno.h>

#include <sys/param.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 <compaterr.h>
#include <stdlib.h>
#elif defined sunos
#include <sys/vnode.h>

#include <ufs/fs.h>
#include <ufs/fsdir.h>
#include <ufs/inode.h>
#else
#include <ufs/ufs/dir.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#endif  /* __linux__ */

#include <protocols/dumprestore.h>

#include "dump.h"

#define HASDUMPEDFILE   0x1
#define HASSUBDIRS      0x2

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

#ifdef  __linux__
static  int searchdir __P((struct ext2_dir_entry *dp, int offset,
                           int blocksize, char *buf, void *private));
#else
static  int dirindir __P((dump_ino_t ino, daddr_t blkno, int level, long *size));
static  void dmpindir __P((dump_ino_t ino, daddr_t blk, int level, fsizeT *size));
static  int searchdir __P((dump_ino_t ino, daddr_t blkno, long size, long filesize));
#endif
static  void mapfileino __P((dump_ino_t ino, struct dinode const *dp, long *tapesize, int *dirskipped));

#ifdef HAVE_EXT2_JOURNAL_INUM
#define ext2_journal_ino(sb) (sb->s_journal_inum)
#else
#define ext2_journal_ino(sb) (*((u_int32_t *)sb + 0x38))
#endif
#ifndef HAVE_EXT2_INO_T
typedef ino_t ext2_ino_t;
#endif

#ifndef EXT3_FEATURE_COMPAT_HAS_JOURNAL
#define EXT3_FEATURE_COMPAT_HAS_JOURNAL         0x0004
#endif
#ifndef EXT2_FEATURE_INCOMPAT_FILETYPE
#define EXT2_FEATURE_INCOMPAT_FILETYPE          0x0002
#endif
#ifndef EXT3_FEATURE_INCOMPAT_RECOVER
#define EXT3_FEATURE_INCOMPAT_RECOVER           0x0004
#endif
#ifndef EXT3_FEATURE_INCOMPAT_JOURNAL_DEV
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008
#endif

#ifndef EXT2_LIB_FEATURE_INCOMPAT_SUPP
#define EXT2_LIB_FEATURE_INCOMPAT_SUPP (EXT3_FEATURE_INCOMPAT_RECOVER | \
                                        EXT2_FEATURE_INCOMPAT_FILETYPE)
#endif
#ifndef EXT2_RESIZE_INO
#define EXT2_RESIZE_INO                 7
#endif
#ifndef EXT2_FT_UNKNOWN
#define EXT2_FT_UNKNOWN         0
#define EXT2_FT_REG_FILE        1
#define EXT2_FT_DIR             2
#define EXT2_FT_CHRDEV          3
#define EXT2_FT_BLKDEV          4
#define EXT2_FT_FIFO            5
#define EXT2_FT_SOCK            6
#define EXT2_FT_SYMLINK         7
#define EXT2_FT_MAX             8
#endif

int dump_fs_open(const char *disk, ext2_filsys *fs)
{
        int retval;

        retval = ext2fs_open(disk, EXT2_FLAG_FORCE, 0, 0, unix_io_manager, fs);
        if (!retval) {
                struct ext2_super_block *es = (*fs)->super;
                dump_ino_t journal_ino = ext2_journal_ino(es);

                if (es->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV){
                        msg("This is a journal, not a filesystem!\n");
                        retval = EXT2_ET_UNSUPP_FEATURE;
                        ext2fs_close(*fs);
                }
                else if ((retval = es->s_feature_incompat &
                                        ~(EXT2_LIB_FEATURE_INCOMPAT_SUPP |
                                          EXT3_FEATURE_INCOMPAT_RECOVER))) {
                        msg("Unsupported feature(s) 0x%x in filesystem\n",
                                retval);
                        retval = EXT2_ET_UNSUPP_FEATURE;
                        ext2fs_close(*fs);
                }
                else {
                        if (es->s_feature_compat &
                                EXT3_FEATURE_COMPAT_HAS_JOURNAL && 
                                journal_ino)
                                do_exclude_ino(journal_ino, "journal inode");
                        do_exclude_ino(EXT2_RESIZE_INO, "resize inode");
                }
        }
        return retval;
}

/*
 * 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 dinode const *dp)
{
        long blkest, sizeest;
        u_quad_t i_size;

        /*
         * 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((u_quad_t)dp->di_blocks * 512, TP_BSIZE);
        i_size = dp->di_size + ((u_quad_t) dp->di_size_high << 32);
        sizeest = howmany(i_size, TP_BSIZE);
        if (blkest > sizeest)
                blkest = sizeest;
#ifdef  __linux__
        if (i_size > (u_quad_t)fs->blocksize * NDADDR) {
                /* calculate the number of indirect blocks on the dump tape */
                blkest +=
                        howmany(sizeest - NDADDR * fs->blocksize / TP_BSIZE,
                        NINDIR(sblock) * EXT2_FRAGS_PER_BLOCK(fs->super));
        }
#else
        if (i_size > sblock->fs_bsize * NDADDR) {
                /* calculate the number of indirect blocks on the dump tape */
                blkest +=
                        howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
                        TP_NINDIR);
        }
#endif
        return (blkest + 1);
}

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

/* The NODUMP_FLAG macro tests if a file has the nodump flag. */
#ifdef UF_NODUMP
#define NODUMP_FLAG(dp) (!nonodump && (((dp)->di_flags & UF_NODUMP) == UF_NODUMP))
#else
#define NODUMP_FLAG(dp) 0
#endif

/* The WANTTODUMP macro decides whether a file should be dumped. */
#define WANTTODUMP(dp, ino) \
        (CHANGEDSINCE(dp, ((u_int32_t)spcl.c_ddate)) && \
         (!NODUMP_FLAG(dp)) && \
         (!exclude_ino(ino)))

/*
 * Determine if given inode should be dumped. "dp" must either point to a
 * copy of the given inode, or be NULL (in which case it is fetched.)
 */
static void
mapfileino(dump_ino_t ino, struct dinode const *dp, long *tapesize, int *dirskipped)
{
        int mode;

        /*
         * Skip inode if we've already marked it for dumping
         */
        if (TSTINO(ino, usedinomap))
                return;
        if (!dp)
                dp = getino(ino);
        if ((mode = (dp->di_mode & IFMT)) == 0)
                return;
#ifdef  __linux__
        if (dp->di_nlink == 0 || dp->di_dtime != 0)
                return;
#endif
        /*
         * Put all dirs in dumpdirmap, inodes that are to be dumped in the
         * used map. All inode but dirs who have the nodump attribute go
         * to the usedinomap.
         */
        SETINO(ino, usedinomap);

        if (mode == IFDIR)
                SETINO(ino, dumpdirmap);
        if (WANTTODUMP(dp, ino)) {
                SETINO(ino, dumpinomap);
                if (!MSINCE(dp, (u_int32_t)spcl.c_ddate))
                        SETINO(ino, metainomap);
                if (mode != IFREG && mode != IFDIR && mode != IFLNK)
                        *tapesize += 1;
                else
                        *tapesize += blockest(dp);
                return;
        }
        if (mode == IFDIR) {
                if ( NODUMP_FLAG(dp) || exclude_ino(ino) )
                        CLRINO(ino, usedinomap);
                *dirskipped = 1;
        }
}

/*
 * 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.
 */
#ifdef __linux__
int
mapfiles(UNUSED(dump_ino_t maxino), long *tapesize)
{
        ext2_ino_t ino;
        int anydirskipped = 0;
        ext2_inode_scan scan;
        errcode_t err;
        struct ext2_inode inode;

        /*
         * We use libext2fs's inode scanning routines, which are particularly
         * robust.  (Note that getino cannot return an error.)
         */
        err = ext2fs_open_inode_scan(fs, 0, &scan);
        if (err) {
                com_err(disk, err, "while opening inodes\n");
                exit(X_ABORT);
        }
        for (;;) {
                err = ext2fs_get_next_inode(scan, &ino, &inode);
                if (err == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
                        continue;
                if (err) {
                        com_err(disk, err, "while scanning inode #%ld\n",
                                (long)ino);
                        exit(X_ABORT);
                }
                if (ino == 0)
                        break;

                curino = ino;
                mapfileino(ino, (struct dinode const *)&inode, tapesize,
                           &anydirskipped);
        }
        ext2fs_close_inode_scan(scan);

        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(ROOTINO, dumpinomap);
        return (anydirskipped);
}
#else
int
mapfiles(dump_ino_t maxino, long *tapesize)
{
        dump_ino_t ino;
        int anydirskipped = 0;

        for (ino = ROOTINO; ino < maxino; ino++)
                mapfileino(ino, tapesize, &anydirskipped);

        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(ROOTINO, dumpinomap);
        return (anydirskipped);
}
#endif /* __linux__ */

#ifdef __linux__
int
maponefile(UNUSED(dump_ino_t maxino), long *tapesize, char *directory)
{
        errcode_t retval;
        ext2_ino_t dir_ino;
        char dir_name [MAXPATHLEN];
        int i, anydirskipped = 0;

        /*
         * Mark every directory in the path as being dumped
         */
        for (i = 0; i < (int)strlen (directory); i++) {
                if (directory[i] == '/') {
                        strncpy (dir_name, directory, i);
                        dir_name[i] = '\0';
                        retval = ext2fs_namei(fs, ROOTINO, ROOTINO, 
                                              dir_name, &dir_ino);
                        if (retval) {
                                com_err(disk, retval, 
                                        "while translating %s", dir_name);
                                exit(X_ABORT);
                        }
                        mapfileino((dump_ino_t) dir_ino, 0,
                                   tapesize, &anydirskipped);
                }
        }
        /*
         * Mark the final directory
         */
        retval = ext2fs_namei(fs, ROOTINO, ROOTINO, directory, &dir_ino);
        if (retval) {
                com_err(disk, retval, "while translating %s", directory);
                exit(X_ABORT);
        }
        mapfileino((dump_ino_t)dir_ino, 0, tapesize, &anydirskipped);

        mapfileino(ROOTINO, 0, tapesize, &anydirskipped);

        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(ROOTINO, dumpdirmap);
        return anydirskipped;
}
#endif /* __linux__ */

#ifdef  __linux__
struct mapfile_context {
        long *tapesize;
        int *anydirskipped;
};

static int
mapfilesindir(struct ext2_dir_entry *dirent, UNUSED(int offset), 
              UNUSED(int blocksize), UNUSED(char *buf), void *private)
{
        struct dinode const *dp;
        int mode;
        errcode_t retval;
        struct mapfile_context *mfc;
        ext2_ino_t ino;

        ino = dirent->inode;
        mfc = (struct mapfile_context *)private;
        dp = getino(dirent->inode);

        mapfileino(dirent->inode, dp, mfc->tapesize, mfc->anydirskipped);

        mode = dp->di_mode & IFMT;
        if (mode == IFDIR && dp->di_nlink != 0 && dp->di_dtime == 0) {
                if ((dirent->name[0] != '.' || ( dirent->name_len & 0xFF ) != 1) &&
                    (dirent->name[0] != '.' || dirent->name[1] != '.' ||
                     ( dirent->name_len & 0xFF ) != 2)) {
                retval = ext2fs_dir_iterate(fs, ino, 0, NULL,
                                            mapfilesindir, private);
                if (retval)
                        return retval;
                }
        }
        return 0;
}

/*
 * 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
mapfilesfromdir(UNUSED(dump_ino_t maxino), long *tapesize, char *directory)
{
        errcode_t retval;
        struct mapfile_context mfc;
        ext2_ino_t dir_ino;
        char dir_name [MAXPATHLEN];
        int i, anydirskipped = 0;

        /*
         * Mark every directory in the path as being dumped
         */
        for (i = 0; i < (int)strlen (directory); i++) {
                if (directory[i] == '/') {
                        strncpy (dir_name, directory, i);
                        dir_name[i] = '\0';
                        retval = ext2fs_namei(fs, ROOTINO, ROOTINO, dir_name,
                                              &dir_ino);
                        if (retval) {
                                com_err(disk, retval, "while translating %s",
                                        dir_name);
                                exit(X_ABORT);
                        }
                        mapfileino(dir_ino, 0, tapesize, &anydirskipped);
                }
        }
        /*
         * Mark the final directory
         */
        retval = ext2fs_namei(fs, ROOTINO, ROOTINO, directory, &dir_ino);
        if (retval) {
                com_err(disk, retval, "while translating %s", directory);
                exit(X_ABORT);
        }
        mapfileino(dir_ino, 0, tapesize, &anydirskipped);

        mfc.tapesize = tapesize;
        mfc.anydirskipped = &anydirskipped;
        retval = ext2fs_dir_iterate(fs, dir_ino, 0, NULL, mapfilesindir,
                                    (void *)&mfc);

        if (retval) {
                com_err(disk, retval, "while mapping files in %s", directory);
                exit(X_ABORT);
        }
        /*
         * Ensure that the root inode actually appears in the file list
         * for a subdir
         */
        mapfileino(ROOTINO, 0, tapesize, &anydirskipped);
        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(ROOTINO, dumpinomap);
        return anydirskipped;
}
#endif

#ifdef __linux__
struct mapdirs_context {
        int *ret;
        int nodump;
        long *tapesize;
};
#endif

/*
 * 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(dump_ino_t maxino, long *tapesize)
{
        struct  dinode *dp;
        int isdir;
        char *map;
        dump_ino_t ino;
#ifndef __linux__
        int i;
        long filesize;
#else
        struct mapdirs_context mdc;
#endif
        int ret, change = 0, nodump;

        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 dir has been removed from the used map, it's either
                 * because it had the nodump flag, or it herited it from
                 * its parent. A directory can't be in dumpinomap if not
                 * in usedinomap, but we have to go through it anyway 
                 * to propagate the nodump attribute.
                 */
                nodump = (TSTINO(ino, usedinomap) == 0);
                if ((isdir & 1) == 0 ||
                    (TSTINO(ino, dumpinomap) && nodump == 0))
                        continue;
                dp = getino(ino);
#ifdef  __linux__
                ret = 0;
                mdc.ret = &ret;
                mdc.nodump = nodump;
                mdc.tapesize = tapesize;
                ext2fs_dir_iterate(fs, ino, 0, NULL, searchdir, (void *) &mdc);
#else   /* __linux__ */
                filesize = dp->di_size;
                for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
                        if (dp->di_db[i] != 0)
                                ret |= searchdir(ino, dp->di_db[i],
                                        (long)dblksize(sblock, dp, i),
                                        filesize);
                        if (ret & HASDUMPEDFILE)
                                filesize = 0;
                        else
                                filesize -= sblock->fs_bsize;
                }
                for (i = 0; filesize > 0 && i < NIADDR; i++) {
                        if (dp->di_ib[i] == 0)
                                continue;
                        ret |= dirindir(ino, dp->di_ib[i], i, &filesize);
                }
#endif  /* __linux__ */
                if (ret & HASDUMPEDFILE) {
                        SETINO(ino, dumpinomap);
                        *tapesize += blockest(dp);
                        change = 1;
                        continue;
                }
                if (nodump) {
                        if (ret & HASSUBDIRS)
                                change = 1; /* subdirs have inherited nodump */
                        CLRINO(ino, dumpdirmap);
                } else if ((ret & HASSUBDIRS) == 0) {
                        if (!TSTINO(ino, dumpinomap)) {
                                CLRINO(ino, dumpdirmap);
                                change = 1;
                        }
                }
        }
        return (change);
}

#ifndef __linux__
/*
 * 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(dump_ino_t ino, daddr_t blkno, int ind_level, long *filesize)
{
        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);
                        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);
        }
        return (ret);
}
#endif  /* !__linux__ */

/*
 * 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.
 */
#ifdef  __linux__
static  int
searchdir(struct ext2_dir_entry *dp, UNUSED(int offset), 
          UNUSED(int blocksize), UNUSED(char *buf), void *private)
{
        struct mapdirs_context *mdc;
        int *ret;
        long *tapesize;
        struct dinode *ip;

        mdc = (struct mapdirs_context *)private;
        ret = mdc->ret;
        tapesize = mdc->tapesize;

        if (dp->inode == 0)
                return 0;
        if (dp->name[0] == '.') {
                if (( dp->name_len & 0xFF ) == 1)
                        return 0;
                if (dp->name[1] == '.' && ( dp->name_len & 0xFF ) == 2)
                        return 0;
        }
        if (mdc->nodump) {
                ip = getino(dp->inode);
                if (TSTINO(dp->inode, dumpinomap)) {
                        CLRINO(dp->inode, dumpinomap);
                        *tapesize -= blockest(ip);
                }
                /* Add dir back to the dir map and remove from
                 * usedinomap to propagate nodump */
                if ((ip->di_mode & IFMT) == IFDIR) {
                        SETINO(dp->inode, dumpdirmap);
                        CLRINO(dp->inode, usedinomap);
                        *ret |= HASSUBDIRS;
                }
        } else {
                if (TSTINO(dp->inode, dumpinomap)) {
                        *ret |= HASDUMPEDFILE;
                        if (*ret & HASSUBDIRS)
                                return DIRENT_ABORT;
                }
                if (TSTINO(dp->inode, dumpdirmap)) {
                        *ret |= HASSUBDIRS;
                        if (*ret & HASDUMPEDFILE)
                                return DIRENT_ABORT;
                }
        }
        return 0;
}

#else   /* __linux__ */

static int
searchdir(dump_ino_t ino, daddr_t blkno, long size, long filesize)
{
        struct direct *dp;
        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 (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);
}
#endif  /* __linux__ */

#ifdef  __linux__

struct block_context {
        ext2_ino_t ino;
        int     *buf;
        int     cnt;
        int     max;
        int     next_block;
};

/*
 * Dump a block to the tape
 */
static int
dumponeblock(UNUSED(ext2_filsys fs), blk_t *blocknr, e2_blkcnt_t blockcnt,
             UNUSED(blk_t ref_block), UNUSED(int ref_offset), void * private)
{
        struct block_context *p;
        int i;

        if (blockcnt < NDADDR)
                return 0;
        p = (struct block_context *)private;
        for (i = p->next_block; i < blockcnt; i++) {
                p->buf[p->cnt++] = 0;
                if (p->cnt == p->max) {
                        blksout (p->buf, p->cnt, p->ino);
                        p->cnt = 0;
                }
        }
        p->buf[p->cnt++] = *blocknr;
        if (p->cnt == p->max) {
                blksout (p->buf, p->cnt, p->ino);
                p->cnt = 0;
        }
        p->next_block = blockcnt + 1;
        return 0;
}
#endif

/*
 * Dump passes 3 and 4.
 *
 * Dump the contents of an inode to tape.
 */
void
dumpino(struct dinode *dp, dump_ino_t ino, int metaonly)
{
        unsigned long cnt;
        fsizeT size, remaining;
        char buf[TP_BSIZE];
        struct new_bsd_inode nbi;
        int i;
#ifdef  __linux__
        struct block_context bc;
#else
        int ind_level;
#endif
        u_quad_t i_size;
        
        if (metaonly)
                i_size = 0;
        else 
                i_size = dp->di_size + ((u_quad_t) dp->di_size_high << 32);

        if (newtape) {
                newtape = 0;
                dumpmap(dumpinomap, TS_BITS, ino);
        }
        CLRINO(ino, dumpinomap);
#ifdef  __linux__
        memset(&nbi, 0, sizeof(nbi));
        nbi.di_mode = dp->di_mode;
        nbi.di_nlink = dp->di_nlink;
        nbi.di_ouid = dp->di_uid;
        nbi.di_ogid = dp->di_gid;
        nbi.di_size = i_size;
        nbi.di_atime.tv_sec = dp->di_atime;
        nbi.di_mtime.tv_sec = dp->di_mtime;
        nbi.di_ctime.tv_sec = dp->di_ctime;
        memmove(&nbi.di_db, &dp->di_db, (NDADDR + NIADDR) * sizeof(daddr_t));
        nbi.di_flags = dp->di_flags;
        nbi.di_blocks = dp->di_blocks;
        nbi.di_gen = dp->di_gen;
        nbi.di_uid = (((int32_t)dp->di_uidhigh) << 16) | dp->di_uid;
        nbi.di_gid = (((int32_t)dp->di_gidhigh) << 16) | dp->di_gid;
        if (dp->di_file_acl)
                msg("ACLs in inode #%ld won't be dumped\n", (long)ino);
        memmove(&spcl.c_dinode, &nbi, sizeof(nbi));
#else   /* __linux__ */
        spcl.c_dinode = *dp;
#endif  /* __linux__ */
        spcl.c_type = TS_INODE;
        spcl.c_count = 0;

        if (metaonly && (dp->di_mode & S_IFMT)) {
                spcl.c_flags |= DR_METAONLY;
                spcl.c_count = 0;
                writeheader(ino);
                spcl.c_flags &= ~DR_METAONLY;
                return;
        }

        switch (dp->di_mode & S_IFMT) {

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

#ifdef  __linux__
        case S_IFDIR:
                msg("Warning: dumpino called on a directory (ino %d)\n", ino);
                return;
#endif

        case S_IFLNK:
                /*
                 * Check for short symbolic link.
                 */
#ifdef  __linux__
                if (i_size > 0 &&
                    i_size < EXT2_N_BLOCKS * sizeof (daddr_t)) {
                        spcl.c_addr[0] = 1;
                        spcl.c_count = 1;
                        writeheader(ino);
                        memmove(buf, dp->di_db, (u_long)dp->di_size);
                        buf[dp->di_size] = '\0';
                        writerec(buf, 0);
                        return;
                }
#endif  /* __linux__ */
#ifdef FS_44INODEFMT
                if (dp->di_size > 0 &&
                    dp->di_size < 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 */

#ifndef __linux__
        case S_IFDIR:
#endif
        case S_IFREG:
                if (i_size)
                        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 (i_size > (u_quad_t)NDADDR * sblock->fs_bsize)
#ifdef  __linux__
                cnt = NDADDR * EXT2_FRAGS_PER_BLOCK(fs->super);
#else
                cnt = NDADDR * sblock->fs_frag;
#endif
        else
                cnt = howmany(i_size, sblock->fs_fsize);
        blksout(&dp->di_db[0], cnt, ino);
        if ((quad_t) (size = i_size - NDADDR * sblock->fs_bsize) <= 0)
                return;
#ifdef  __linux__
        bc.max = NINDIR(sblock) * EXT2_FRAGS_PER_BLOCK(fs->super);
        bc.buf = (int *)malloc (bc.max * sizeof (int));
        bc.cnt = 0;
        bc.ino = ino;
        bc.next_block = NDADDR;

        ext2fs_block_iterate2(fs, (ext2_ino_t)ino, 0, NULL, dumponeblock, (void *)&bc);
        /* deal with holes at the end of the inode */
        if (i_size > ((u_quad_t)bc.next_block) * sblock->fs_fsize) {
                remaining = i_size - ((u_quad_t)bc.next_block) * sblock->fs_fsize;
                for (i = 0; i < (int)howmany(remaining, sblock->fs_fsize); i++) {
                        bc.buf[bc.cnt++] = 0;
                        if (bc.cnt == bc.max) {
                                blksout (bc.buf, bc.cnt, bc.ino);
                                bc.cnt = 0;
                        }
                }
        }
        if (bc.cnt > 0) {
                blksout (bc.buf, bc.cnt, bc.ino);
        }
        free(bc.buf);
#else
        for (ind_level = 0; ind_level < NIADDR; ind_level++) {
                dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
                if (size <= 0)
                        return;
        }
#endif
}

#ifdef  __linux__

struct convert_dir_context {
        char *buf;
        int prev_offset;
        int offset;
        int bs;
};

/*
 * This function converts an ext2fs directory entry to the BSD format.
 *
 * Basically, it adds a null-character at the end of the name, recomputes the
 * size of the entry, and creates it in a temporary buffer
 */
static int
convert_dir(struct ext2_dir_entry *dirent, UNUSED(int offset), 
            UNUSED(int blocksize), UNUSED(char *buf), void *private)
{
        struct convert_dir_context *p;
        struct direct *dp;
        int reclen;

        p = (struct convert_dir_context *)private;

        reclen = EXT2_DIR_REC_LEN((dirent->name_len & 0xFF) + 1);
        if (((p->offset + reclen - 1) / p->bs) != (p->offset / p->bs)) {
                dp = (struct direct *)(p->buf + p->prev_offset);
                dp->d_reclen += p->bs - (p->offset % p->bs);
                p->offset += p->bs - (p->offset % p->bs);
        }

        dp = (struct direct *)(p->buf + p->offset);
        dp->d_ino = dirent->inode;
        dp->d_reclen = reclen;
        dp->d_namlen = dirent->name_len & 0xFF;
        switch ((dirent->name_len & 0xFF00) >> 8) {
        default:
                dp->d_type = DT_UNKNOWN;
                break;
        case EXT2_FT_REG_FILE:
                dp->d_type = DT_REG;
                break;
        case EXT2_FT_DIR:
                dp->d_type = DT_DIR;
                break;
        case EXT2_FT_CHRDEV:
                dp->d_type = DT_CHR;
                break;
        case EXT2_FT_BLKDEV:
                dp->d_type = DT_BLK;
                break;
        case EXT2_FT_FIFO:
                dp->d_type = DT_FIFO;
                break;
        case EXT2_FT_SOCK:
                dp->d_type = DT_SOCK;
                break;
        case EXT2_FT_SYMLINK:
                dp->d_type = DT_LNK;
                break;
        }
        strncpy(dp->d_name, dirent->name, dp->d_namlen);
        dp->d_name[dp->d_namlen] = '\0';
        p->prev_offset = p->offset;
        p->offset += reclen;

        return 0;
}

/*
 * Dump pass 3
 *
 * Dumps a directory to tape after converting it to the BSD format
 */
void
dumpdirino(struct dinode *dp, dump_ino_t ino)
{
        fsizeT size;
        char buf[TP_BSIZE];
        struct new_bsd_inode nbi;
        struct convert_dir_context cdc;
        errcode_t retval;
        struct ext2_dir_entry *de;
        fsizeT dir_size;

        if (newtape) {
                newtape = 0;
                dumpmap(dumpinomap, TS_BITS, ino);
        }
        CLRINO(ino, dumpinomap);

        /*
         * Convert the directory to the BSD format
         */
        /* Allocate a buffer for the conversion (twice the size of the
           ext2fs directory to avoid problems ;-) */
        cdc.buf = (char *)malloc(dp->di_size * 2 * sizeof(char));
        if (cdc.buf == NULL)
                err(1, "Cannot allocate buffer to convert directory #%lu\n",
                    (unsigned long)ino);
        cdc.offset = 0;
        cdc.prev_offset = 0;
        cdc.bs = MIN(DIRBLKSIZ, TP_BSIZE);
        /* Do the conversion */
        retval = ext2fs_dir_iterate(fs, (ext2_ino_t)ino, 0, NULL, convert_dir, (void *)&cdc);
        if (retval) {
                com_err(disk, retval, "while converting directory #%ld\n", (long)ino);
                exit(X_ABORT);
        }
        /* Fix the last entry */
        if ((cdc.offset % cdc.bs) != 0) {
                de = (struct ext2_dir_entry *)(cdc.buf + cdc.prev_offset);
                de->rec_len += cdc.bs - (cdc.offset % cdc.bs);
                cdc.offset += cdc.bs - (cdc.offset % cdc.bs);
        }

        dir_size = cdc.offset;

#ifdef  __linux__
        memset(&nbi, 0, sizeof(nbi));
        nbi.di_mode = dp->di_mode;
        nbi.di_nlink = dp->di_nlink;
        nbi.di_ouid = dp->di_uid;
        nbi.di_ogid = dp->di_gid;
        nbi.di_size = dir_size; /* (u_quad_t)dp->di_size; */
        nbi.di_atime.tv_sec = dp->di_atime;
        nbi.di_mtime.tv_sec = dp->di_mtime;
        nbi.di_ctime.tv_sec = dp->di_ctime;
        memmove(&nbi.di_db, &dp->di_db, (NDADDR + NIADDR) * sizeof(daddr_t));
        nbi.di_flags = dp->di_flags;
        nbi.di_blocks = dp->di_blocks;
        nbi.di_gen = dp->di_gen;
        nbi.di_uid = (((int32_t)dp->di_uidhigh) << 16) | dp->di_uid;
        nbi.di_gid = (((int32_t)dp->di_gidhigh) << 16) | dp->di_gid;
        if (dp->di_file_acl)
                msg("ACLs in inode #%ld won't be dumped\n", (long)ino);
        memmove(&spcl.c_dinode, &nbi, sizeof(nbi));
#else   /* __linux__ */
        spcl.c_dinode = *dp;
#endif  /* __linux__ */
        spcl.c_type = TS_INODE;
        spcl.c_count = 0;
        switch (dp->di_mode & S_IFMT) {

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

        case S_IFDIR:
                if (dir_size > 0)
                        break;
                msg("Warning: size of directory inode #%d is <= 0 (%d)!\n",
                        ino, dir_size);
                return;

        default:
                msg("Warning: dumpdirino called with file type 0%o (inode #%d)\n",
                        dp->di_mode & IFMT, ino);
                return;
        }
        for (size = 0; size < dir_size; size += TP_BSIZE) {
                spcl.c_addr[0] = 1;
                spcl.c_count = 1;
                writeheader(ino);
                memmove(buf, cdc.buf + size, TP_BSIZE);
                writerec(buf, 0);
                spcl.c_type = TS_ADDR;
        }

        (void)free(cdc.buf);
}
#endif  /* __linux__ */

#ifndef __linux__
/*
 * Read indirect blocks, and pass the data blocks to be dumped.
 */
static void
dmpindir(dump_ino_t ino, daddr_t blk, int ind_level, fsizeT *size)
{
        int i, cnt;
#ifdef __linux__
        int max;
        blk_t *swapme;
#endif
        daddr_t idblk[MAXNINDIR];

        if (blk != 0) {
                bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
#ifdef __linux__
        /* 
         * My RedHat 4.0 system doesn't have these flags; I haven't
         * upgraded e2fsprogs yet
         */
#if defined(EXT2_FLAG_SWAP_BYTES)
        if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
            (fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
#endif
        {
                max = sblock->fs_bsize >> 2;
                swapme = (blk_t *) idblk;
                for (i = 0; i < max; i++, swapme++)
                        *swapme = ext2fs_swab32(*swapme);
        }
#endif /* __linux__ */
        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
#ifdef  __linux__
                        cnt = NINDIR(sblock) * EXT2_FRAGS_PER_BLOCK(fs->super);
#else
                        cnt = NINDIR(sblock) * sblock->fs_frag;
#endif
                *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;
        }
}
#endif

/*
 * Collect up the data into tape record sized buffers and output them.
 */
void
blksout(daddr_t *blkp, int frags, dump_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(char *map, int type, dump_ino_t ino)
{
        int i;
        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);
}

#if defined(__linux__) && !defined(int32_t)
#define int32_t __s32
#endif

/* 
 * Compute and fill in checksum information.
 */
void
mkchecksum(union u_spcl *tmpspcl) 
{
        int32_t sum, cnt, *lp;

        tmpspcl->s_spcl.c_checksum = 0;
        lp = (int32_t *)&tmpspcl->s_spcl;
        sum = 0;
        cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
        while (--cnt >= 0) {
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
        }
        tmpspcl->s_spcl.c_checksum = CHECKSUM - sum;
}

/*
 * Write a header record to the dump tape.
 */
void
writeheader(dump_ino_t ino)
{
        spcl.c_inumber = ino;
        spcl.c_magic = NFS_MAGIC;
        mkchecksum((union u_spcl *)&spcl);
        writerec((char *)&spcl, 1);
}

#ifdef  __linux__
struct dinode *
getino(dump_ino_t inum)
{
        static struct dinode dinode;
        errcode_t err;

        curino = inum;
        err = ext2fs_read_inode(fs, (ext2_ino_t)inum, (struct ext2_inode *) &dinode);
        if (err) {
                com_err(disk, err, "while reading inode #%ld\n", (long)inum);
                exit(X_ABORT);
        }
        return &dinode;
}
#else   /* __linux__ */
struct dinode *
getino(dump_ino_t inum)
{
        static daddr_t minino, maxino;
        static struct dinode inoblock[MAXINOPB];

        curino = inum;
        if (inum >= minino && inum < 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]);
}
#endif  /* __linux__ */

/*
 * 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;

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

loop:
#ifdef  __linux__
        if (ext2fs_llseek(diskfd, (((ext2_loff_t)blkno) << dev_bshift), 0) !=
                        (((ext2_loff_t)blkno) << dev_bshift))
#else
        if (lseek(diskfd, ((off_t)blkno << dev_bshift), 0) !=
                                                ((off_t)blkno << dev_bshift))
#endif
                msg("bread: lseek fails\n");
        if ((cnt = read(diskfd, buf, size)) == 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, ext2blk %d]: count=%d\n",
                        disk, strerror(errno), blkno, 
                        dbtofsb(sblock, blkno), size);
        else
                msg("short read error from %s: [block %d, ext2blk %d]: count=%d, got=%d\n",
                        disk, blkno, dbtofsb(sblock, blkno), size, cnt);
        if (breademax && ++breaderrors > breademax) {
                msg("More than %d block read errors from %d\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.
         */
        memset(buf, 0, size);
        for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
#ifdef  __linux__
                if (ext2fs_llseek(diskfd, (((ext2_loff_t)blkno) << dev_bshift), 0) !=
                                (((ext2_loff_t)blkno) << dev_bshift))
#else
                if (lseek(diskfd, ((off_t)blkno << dev_bshift), 0) !=
                                                ((off_t)blkno << dev_bshift))
#endif
                        msg("bread: lseek2 fails!\n");
                if ((cnt = read(diskfd, buf, (int)dev_bsize)) == dev_bsize)
                        continue;
                if (cnt == -1) {
                        msg("read error from %s: %s: [sector %d, ext2blk %d]: count=%d\n",
                                disk, strerror(errno), blkno, 
                                dbtofsb(sblock, blkno), dev_bsize);
                        continue;
                }
                msg("short read error from %s: [sector %d, ext2blk %d]: count=%d, got=%d\n",
                        disk, blkno, dbtofsb(sblock, blkno), dev_bsize, cnt);
        }
}