ext2fs support added
authorstroese <stroese>
Thu, 16 Dec 2004 17:26:24 +0000 (17:26 +0000)
committerstroese <stroese>
Thu, 16 Dec 2004 17:26:24 +0000 (17:26 +0000)
fs/Makefile
fs/ext2/Makefile [new file with mode: 0644]
fs/ext2/dev.c [new file with mode: 0644]
fs/ext2/ext2fs.c [new file with mode: 0644]

index c7507905d5a7a4d31bdfaaa3757b82f62075b969..79cbdeaa7a9dd271bd3c32577053c2c6dfbef123 100644 (file)
@@ -22,7 +22,7 @@
 #
 #
 
-SUBDIRS        := jffs2 cramfs fdos fat reiserfs
+SUBDIRS        := jffs2 cramfs fdos fat reiserfs ext2
 
 .depend all:
        @for dir in $(SUBDIRS) ; do \
diff --git a/fs/ext2/Makefile b/fs/ext2/Makefile
new file mode 100644 (file)
index 0000000..3b19368
--- /dev/null
@@ -0,0 +1,48 @@
+#
+# (C) Copyright 2003
+# Pavel Bartusek, Sysgo Real-Time Solutions AG, pba@sysgo.de
+#
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+include $(TOPDIR)/config.mk
+
+LIB    = libext2fs.a
+
+AOBJS  =
+COBJS  = ext2fs.o dev.o
+OBJS   = $(AOBJS) $(COBJS)
+
+#CPPFLAGS +=
+
+all:   $(LIB) $(AOBJS)
+
+$(LIB):        .depend $(OBJS)
+       $(AR) crv $@ $(OBJS)
+
+
+#########################################################################
+
+.depend:       Makefile $(AOBJS:.o=.S) $(COBJS:.o=.c)
+               $(CC) -M $(CFLAGS) $(AOBJS:.o=.S) $(COBJS:.o=.c) > $@
+
+sinclude .depend
+
+#########################################################################
diff --git a/fs/ext2/dev.c b/fs/ext2/dev.c
new file mode 100644 (file)
index 0000000..117a449
--- /dev/null
@@ -0,0 +1,142 @@
+/*
+ * (C) Copyright 2004
+ *  esd gmbh <www.esd-electronics.com>
+ *  Reinhard Arlt <reinhard.arlt@esd-electronics.com>
+ *
+ *  based on code of fs/reiserfs/dev.c by
+ *
+ *  (C) Copyright 2003 - 2004
+ *  Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <common.h>
+#if (CONFIG_COMMANDS & CFG_CMD_EXT2)
+
+#include <config.h>
+#include <ext2fs.h>
+
+static block_dev_desc_t *ext2fs_block_dev_desc;
+static disk_partition_t part_info;
+
+#undef DEBUG
+int ext2fs_set_blk_dev
+    (
+    block_dev_desc_t *rbdd, 
+    int               part
+    )
+    {
+    ext2fs_block_dev_desc = rbdd;
+
+    if (part == 0) 
+        {
+       /* disk doesn't use partition table */
+       part_info.start = 0;
+       part_info.size = rbdd->lba;
+       part_info.blksz = rbdd->blksz;
+       } 
+    else 
+        {
+       if (get_partition_info (ext2fs_block_dev_desc, part, &part_info)) 
+           {
+           return 0;
+           }
+       }
+    return (part_info.size);
+    }
+
+
+int ext2fs_devread 
+    (
+    int   sector, 
+    int   byte_offset, 
+    int   byte_len, 
+    char *buf
+    )
+    {
+    char sec_buf[SECTOR_SIZE];
+    unsigned block_len;
+/*
+ *  Check partition boundaries
+ */
+    if ((sector < 0) || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) >= part_info.size)) 
+        {
+/*      errnum = ERR_OUTSIDE_PART; */
+       printf (" ** ext2fs_devread() read outside partition sector %d\n", sector);
+       return(0);
+       }
+
+/*
+ *  Get the read to the beginning of a partition.
+ */
+    sector += byte_offset >> SECTOR_BITS;
+    byte_offset &= SECTOR_SIZE - 1;
+
+#if defined(DEBUG)
+    printf (" <%d, %d, %d>\n", sector, byte_offset, byte_len);
+#endif
+
+    if (ext2fs_block_dev_desc == NULL)
+        {
+        printf("** Invalid Block Device Descriptor (NULL)\n");
+       return(0);
+       }
+
+    if (byte_offset != 0) 
+        {
+/*      read first part which isn't aligned with start of sector */
+       if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev, part_info.start+sector, 1, (unsigned long *)sec_buf) != 1) 
+           {
+           printf (" ** ext2fs_devread() read error **\n");
+           return(0);
+           }
+       memcpy(buf, sec_buf+byte_offset, min(SECTOR_SIZE-byte_offset, byte_len));
+       buf+=min(SECTOR_SIZE-byte_offset, byte_len);
+       byte_len-=min(SECTOR_SIZE-byte_offset, byte_len);
+       sector++;
+       }
+
+/*  read sector aligned part */
+    block_len = byte_len & ~(SECTOR_SIZE-1);
+    if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev, 
+                                         part_info.start+sector, 
+                                         block_len/SECTOR_SIZE, 
+                                         (unsigned long *)buf) != block_len/SECTOR_SIZE) 
+        {
+       printf (" ** ext2fs_devread() read error - block\n");
+       return(0);
+       }
+    buf+=block_len;
+    byte_len-=block_len;
+    sector+= block_len/SECTOR_SIZE;
+
+    if (byte_len != 0) 
+        {
+/*      read rest of data which are not in whole sector */
+       if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev,
+                                             part_info.start+sector, 
+                                             1, 
+                                             (unsigned long *)sec_buf) != 1) 
+           {
+           printf (" ** ext2fs_devread() read error - last part\n");
+           return(0);
+           }
+       memcpy(buf, sec_buf, byte_len);
+       }
+    return(1);
+    }
+#endif /* CFG_CMD_EXT2FS */
diff --git a/fs/ext2/ext2fs.c b/fs/ext2/ext2fs.c
new file mode 100644 (file)
index 0000000..bae72a3
--- /dev/null
@@ -0,0 +1,1004 @@
+/*
+ * (C) Copyright 2004
+ *  esd gmbh <www.esd-electronics.com>
+ *  Reinhard Arlt <reinhard.arlt@esd-electronics.com>
+ *
+ *  based on code from grub2 fs/ext2.c and fs/fshelp.c by
+ *
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2003, 2004  Free Software Foundation, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_EXT2)
+#include <ext2fs.h>
+#include <malloc.h>
+#include <asm/byteorder.h>
+
+extern int ext2fs_devread (int sector, int byte_offset, int byte_len, char *buf);
+
+/* Magic value used to identify an ext2 filesystem.  */
+#define        EXT2_MAGIC              0xEF53
+/* Amount of indirect blocks in an inode.  */
+#define INDIRECT_BLOCKS                12
+/* Maximum lenght of a pathname.  */
+#define EXT2_PATH_MAX          4096
+/* Maximum nesting of symlinks, used to prevent a loop.  */
+#define        EXT2_MAX_SYMLINKCNT     8
+
+/* Filetype used in directory entry.  */
+#define        FILETYPE_UNKNOWN        0
+#define        FILETYPE_REG            1
+#define        FILETYPE_DIRECTORY      2
+#define        FILETYPE_SYMLINK        7
+
+/* Filetype information as used in inodes.  */
+#define FILETYPE_INO_MASK      0170000
+#define FILETYPE_INO_REG       0100000
+#define FILETYPE_INO_DIRECTORY 0040000
+#define FILETYPE_INO_SYMLINK   0120000
+
+/* Bits used as offset in sector */
+#define DISK_SECTOR_BITS        9
+
+/* Log2 size of ext2 block in 512 blocks.  */
+#define LOG2_EXT2_BLOCK_SIZE(data) (__le32_to_cpu (data->sblock.log2_block_size) + 1)
+
+/* Log2 size of ext2 block in bytes.  */
+#define LOG2_BLOCK_SIZE(data)     (__le32_to_cpu (data->sblock.log2_block_size) + 10)
+
+/* The size of an ext2 block in bytes.  */
+#define EXT2_BLOCK_SIZE(data)     (1 << LOG2_BLOCK_SIZE(data))
+
+/* The ext2 superblock.  */
+struct ext2_sblock
+{
+       uint32_t total_inodes;
+       uint32_t total_blocks;
+       uint32_t reserved_blocks;
+       uint32_t free_blocks;
+       uint32_t free_inodes;
+       uint32_t first_data_block;
+       uint32_t log2_block_size;
+       uint32_t log2_fragment_size;
+       uint32_t blocks_per_group;
+       uint32_t fragments_per_group;
+       uint32_t inodes_per_group;
+       uint32_t mtime;
+       uint32_t utime;
+       uint16_t mnt_count;
+       uint16_t max_mnt_count;
+       uint16_t magic;
+       uint16_t fs_state;
+       uint16_t error_handling;
+       uint16_t minor_revision_level;
+       uint32_t lastcheck;
+       uint32_t checkinterval;
+       uint32_t creator_os;
+       uint32_t revision_level;
+       uint16_t uid_reserved;
+       uint16_t gid_reserved;
+       uint32_t first_inode;
+       uint16_t inode_size;
+       uint16_t block_group_number;
+       uint32_t feature_compatibility;
+       uint32_t feature_incompat;
+       uint32_t feature_ro_compat;
+       uint32_t unique_id[4];
+       char volume_name[16];
+       char last_mounted_on[64];
+       uint32_t compression_info;
+};
+
+/* The ext2 blockgroup.  */
+struct ext2_block_group
+{
+       uint32_t block_id;
+       uint32_t inode_id;
+       uint32_t inode_table_id;
+       uint16_t free_blocks;
+       uint16_t free_inodes;
+       uint16_t pad;
+       uint32_t reserved[3];
+};
+
+/* The ext2 inode.  */
+struct ext2_inode
+{
+       uint16_t mode;
+       uint16_t uid;
+       uint32_t size;
+       uint32_t atime;
+       uint32_t ctime;
+       uint32_t mtime;
+       uint32_t dtime;
+       uint16_t gid;
+       uint16_t nlinks;
+       uint32_t blockcnt;  /* Blocks of 512 bytes!! */
+       uint32_t flags;
+       uint32_t osd1;
+       union
+        {
+               struct datablocks
+               {
+                       uint32_t dir_blocks[INDIRECT_BLOCKS];
+                       uint32_t indir_block;
+                       uint32_t double_indir_block;
+                       uint32_t tripple_indir_block;
+               } blocks;
+               char symlink[60];
+        } b;
+       uint32_t version;
+       uint32_t acl;
+       uint32_t dir_acl;
+       uint32_t fragment_addr;
+       uint32_t osd2[3];
+};
+
+/* The header of an ext2 directory entry.  */
+struct ext2_dirent
+{
+       uint32_t inode;
+       uint16_t direntlen;
+       uint8_t  namelen;
+       uint8_t  filetype;
+};
+
+struct ext2fs_node
+{
+       struct ext2_data *data;
+       struct ext2_inode inode;
+       int               ino;
+       int               inode_read;
+};
+
+/* Information about a "mounted" ext2 filesystem.  */
+struct ext2_data
+{
+       struct ext2_sblock sblock;
+       struct ext2_inode *inode;
+       struct ext2fs_node diropen;
+};
+
+
+typedef struct ext2fs_node *ext2fs_node_t;
+
+struct ext2_data *ext2fs_root  = NULL;
+ext2fs_node_t     ext2fs_file  = NULL;
+int               symlinknest  = 0;
+uint32_t         *indir1_block = NULL;
+int               indir1_size  = 0;
+int               indir1_blkno = -1;
+uint32_t         *indir2_block = NULL;
+int               indir2_size  = 0;
+int               indir2_blkno = -1;
+
+
+static int ext2fs_blockgroup
+(
+       struct ext2_data         *data,
+       int                      group,
+       struct ext2_block_group *blkgrp
+       )
+{
+#ifdef DEBUG
+       printf("ext2fs read blockgroup\n");
+#endif
+       return(ext2fs_devread (((__le32_to_cpu (data->sblock.first_data_block) + 1) << LOG2_EXT2_BLOCK_SIZE (data)),
+                              group * sizeof (struct ext2_block_group),
+                              sizeof (struct ext2_block_group),
+                              (char *) blkgrp));
+}
+
+
+static int ext2fs_read_inode
+(
+       struct ext2_data        *data,
+       int                      ino,
+       struct ext2_inode       *inode
+       )
+{
+       struct ext2_block_group  blkgrp;
+       struct ext2_sblock      *sblock = &data->sblock;
+       int                      inodes_per_block;
+       int                      status;
+
+       unsigned int             blkno;
+       unsigned int             blkoff;
+
+       /* It is easier to calculate if the first inode is 0.  */
+       ino--;
+#ifdef DEBUG
+       printf("ext2fs read inode %d\n", ino);
+#endif
+       status = ext2fs_blockgroup (data, ino / __le32_to_cpu(sblock->inodes_per_group), &blkgrp);
+       if (status == 0)
+        {
+               return(0);
+       }
+       inodes_per_block = EXT2_BLOCK_SIZE (data) / 128;
+       blkno =  (ino % __le32_to_cpu (sblock->inodes_per_group)) / inodes_per_block;
+       blkoff = (ino % __le32_to_cpu (sblock->inodes_per_group)) % inodes_per_block;
+#ifdef DEBUG
+       printf("ext2fs read inode blkno %d blkoff %d\n", blkno, blkoff);
+#endif
+       /* Read the inode.  */
+       status = ext2fs_devread(((__le32_to_cpu (blkgrp.inode_table_id) + blkno) << LOG2_EXT2_BLOCK_SIZE (data)),
+                               sizeof (struct ext2_inode) * blkoff,
+                               sizeof (struct ext2_inode),
+                               (char *) inode);
+       if (status == 0)
+        {
+               return(0);
+       }
+       return(1);
+}
+
+
+void ext2fs_free_node
+(
+       ext2fs_node_t node,
+       ext2fs_node_t currroot
+       )
+{
+       if ((node != &ext2fs_root->diropen) && (node != currroot))
+        {
+               free (node);
+       }
+}
+
+
+static int ext2fs_read_block
+(
+       ext2fs_node_t node,
+       int           fileblock
+       )
+{
+       struct ext2_data  *data       = node->data;
+       struct ext2_inode *inode      = &node->inode;
+       int                blknr;
+       int                blksz      = EXT2_BLOCK_SIZE (data);
+       int                log2_blksz = LOG2_EXT2_BLOCK_SIZE (data);
+       int                status;
+
+       /* Direct blocks.  */
+       if (fileblock < INDIRECT_BLOCKS)
+        {
+               blknr = __le32_to_cpu (inode->b.blocks.dir_blocks[fileblock]);
+        }
+       /* Indirect.  */
+       else if (fileblock < (INDIRECT_BLOCKS + (blksz/4)))
+        {
+               if (indir1_block == NULL)
+               {
+                       indir1_block = (uint32_t *) malloc(blksz);
+                       if (indir1_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 1) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir1_size  = blksz;
+                       indir1_blkno = -1;
+               }
+               if (blksz != indir1_size)
+               {
+                       free(indir1_block);
+                       indir1_block = NULL;
+                       indir1_size  = 0;
+                       indir1_blkno = -1;
+                       indir1_block = (uint32_t *) malloc(blksz);
+                       if (indir1_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 1) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir1_size  = blksz;
+               }
+               if ((__le32_to_cpu(inode->b.blocks.indir_block) << log2_blksz) != indir1_blkno)
+               {
+                       status = ext2fs_devread (__le32_to_cpu(inode->b.blocks.indir_block) << log2_blksz, 0, blksz, (char *) indir1_block);
+                       if (status == 0)
+                       {
+                               printf("** ext2fs read block (indir 1) failed. **\n");
+                               return(0);
+                       }
+                       indir1_blkno = __le32_to_cpu(inode->b.blocks.indir_block) << log2_blksz;
+               }
+               blknr = __le32_to_cpu(indir1_block[fileblock - INDIRECT_BLOCKS]);
+       }
+       /* Double indirect.  */
+       else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * (blksz  / 4 + 1))))
+        {
+               unsigned int perblock = blksz / 4;
+               unsigned int rblock = fileblock - (INDIRECT_BLOCKS
+                                                  + blksz / 4);
+
+               if (indir1_block == NULL)
+               {
+                       indir1_block = (uint32_t *) malloc(blksz);
+                       if (indir1_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 2 1) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir1_size  = blksz;
+                       indir1_blkno = -1;
+               }
+               if (blksz != indir1_size)
+               {
+                       free(indir1_block);
+                       indir1_block = NULL;
+                       indir1_size  = 0;
+                       indir1_blkno = -1;
+                       indir1_block = (uint32_t *) malloc(blksz);
+                       if (indir1_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 2 1) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir1_size  = blksz;
+               }
+               if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << log2_blksz) != indir1_blkno)
+               {
+                       status = ext2fs_devread (__le32_to_cpu(inode->b.blocks.double_indir_block) << log2_blksz, 0, blksz, (char *) indir1_block);
+                       if (status == 0)
+                       {
+                               printf("** ext2fs read block (indir 2 1) failed. **\n");
+                               return(-1);
+                       }
+                       indir1_blkno = __le32_to_cpu(inode->b.blocks.double_indir_block) << log2_blksz;
+               }
+
+               if (indir2_block == NULL)
+               {
+                       indir2_block = (uint32_t *) malloc(blksz);
+                       if (indir2_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 2 2) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir2_size  = blksz;
+                       indir2_blkno = -1;
+               }
+               if (blksz != indir2_size)
+               {
+                       free(indir2_block);
+                       indir2_block = NULL;
+                       indir2_size  = 0;
+                       indir2_blkno = -1;
+                       indir2_block = (uint32_t *) malloc(blksz);
+                       if (indir2_block == NULL)
+                       {
+                               printf("** ext2fs read block (indir 2 2) malloc failed. **\n");
+                               return(-1);
+                       }
+                       indir2_size  = blksz;
+               }
+               if ((__le32_to_cpu(indir1_block[rblock / perblock]) << log2_blksz) != indir1_blkno)
+               {
+                       status = ext2fs_devread(__le32_to_cpu(indir1_block[rblock / perblock]) << log2_blksz, 0, blksz, (char *) indir2_block);
+                       if (status == 0)
+                       {
+                               printf("** ext2fs read block (indir 2 2) failed. **\n");
+                               return(-1);
+                       }
+                       indir2_blkno = __le32_to_cpu(indir1_block[rblock / perblock]) << log2_blksz;
+               }
+               blknr = __le32_to_cpu(indir2_block[rblock % perblock]);
+       }
+       /* Tripple indirect.  */
+       else
+        {
+               printf("** ext2fs doesn't support tripple indirect blocks. **\n");
+               return(-1);
+        }
+#ifdef DEBUG
+       printf("ext2fs_read_block %08x\n", blknr);
+#endif
+       return(blknr);
+}
+
+
+int ext2fs_read_file
+(
+       ext2fs_node_t node,
+       int           pos,
+       unsigned int  len,
+       char         *buf
+       )
+{
+       int          i;
+       int          blockcnt;
+       int          log2blocksize = LOG2_EXT2_BLOCK_SIZE (node->data);
+       int          blocksize     = 1 << (log2blocksize + DISK_SECTOR_BITS);
+       unsigned int filesize      = node->inode.size;
+
+       /* Adjust len so it we can't read past the end of the file.  */
+       if (len > filesize)
+        {
+               len = filesize;
+       }
+       blockcnt = ((len + pos)  + blocksize - 1) / blocksize;
+
+       for (i = pos / blocksize; i < blockcnt; i++)
+        {
+               int blknr;
+               int blockoff = pos % blocksize;
+               int blockend = blocksize;
+
+               int skipfirst = 0;
+
+               blknr = ext2fs_read_block(node, i);
+               if (blknr < 0)
+               {
+                       return(-1);
+               }
+               blknr = blknr << log2blocksize;
+
+               /* Last block.  */
+               if (i == blockcnt - 1)
+               {
+                       blockend = (len + pos) % blocksize;
+
+                       /* The last portion is exactly blocksize.  */
+                       if (!blockend)
+                       {
+                               blockend = blocksize;
+                       }
+               }
+
+               /* First block.  */
+               if (i == pos / blocksize)
+               {
+                       skipfirst = blockoff;
+                       blockend -= skipfirst;
+               }
+
+               /* If the block number is 0 this block is not stored on disk but
+                  is zero filled instead.  */
+               if (blknr)
+               {
+                       int status;
+
+                       status = ext2fs_devread (blknr, skipfirst, blockend, buf);
+                       if (status == 0)
+                       {
+                               return(-1);
+                       }
+               }
+               else
+               {
+                       memset (buf, blocksize - skipfirst, 0);
+               }
+               buf += blocksize - skipfirst;
+        }
+       return(len);
+}
+
+
+static int ext2fs_iterate_dir
+(
+       ext2fs_node_t  dir,
+       char          *name,
+       ext2fs_node_t *fnode,
+       int           *ftype
+       )
+{
+       unsigned int fpos = 0;
+       int          status;
+       struct ext2fs_node *diro = (struct ext2fs_node *) dir;
+#ifdef DEBUG
+       if (name != NULL) printf("Iterate dir %s\n", name);
+#endif /* of DEBUG */
+       if (!diro->inode_read)
+        {
+               status = ext2fs_read_inode (diro->data, diro->ino, &diro->inode);
+               if (status == 0)
+               {
+                       return(0);
+               }
+       }
+       /* Search the file.  */
+       while (fpos < __le32_to_cpu (diro->inode.size))
+        {
+               struct ext2_dirent dirent;
+
+               status = ext2fs_read_file (diro, fpos, sizeof (struct ext2_dirent), (char *) &dirent);
+               if (status < 1)
+               {
+                       return(0);
+               }
+               if (dirent.namelen != 0)
+               {
+                       char               filename[dirent.namelen + 1];
+                       ext2fs_node_t      fdiro;
+                       int                type = FILETYPE_UNKNOWN;
+
+                       status = ext2fs_read_file (diro, fpos + sizeof (struct ext2_dirent), dirent.namelen, filename);
+                       if (status < 1)
+                       {
+                               return(0);
+                       }
+                       fdiro = malloc (sizeof (struct ext2fs_node));
+                       if (!fdiro)
+                       {
+                               return(0);
+                       }
+
+                       fdiro->data = diro->data;
+                       fdiro->ino  =  __le32_to_cpu(dirent.inode);
+
+                       filename[dirent.namelen] = '\0';
+
+                       if (dirent.filetype != FILETYPE_UNKNOWN)
+                       {
+                               fdiro->inode_read = 0;
+
+                               if (dirent.filetype == FILETYPE_DIRECTORY)
+                               {
+                                       type = FILETYPE_DIRECTORY;
+                               }
+                               else if (dirent.filetype == FILETYPE_SYMLINK)
+                               {
+                                       type = FILETYPE_SYMLINK;
+                               }
+                               else if (dirent.filetype == FILETYPE_REG)
+                               {
+                                       type =  FILETYPE_REG;
+                               }
+                       }
+                       else
+                       {
+                               /* The filetype can not be read from the dirent, get it from inode */
+
+                               status = ext2fs_read_inode (diro->data, __le32_to_cpu (dirent.inode), &fdiro->inode);
+                               if (status == 0)
+                               {
+                                       free(fdiro);
+                                       return(0);
+                               }
+                               fdiro->inode_read = 1;
+
+                               if ((__le16_to_cpu (fdiro->inode.mode) & FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY)
+                               {
+                                       type = FILETYPE_DIRECTORY;
+                               }
+                               else if ((__le16_to_cpu (fdiro->inode.mode) & FILETYPE_INO_MASK) == FILETYPE_INO_SYMLINK)
+                               {
+                                       type = FILETYPE_SYMLINK;
+                               }
+                               else if ((__le16_to_cpu (fdiro->inode.mode) & FILETYPE_INO_MASK) == FILETYPE_INO_REG)
+                               {
+                                       type = FILETYPE_REG;
+                               }
+                       }
+#ifdef DEBUG
+                       printf("iterate >%s<\n", filename);
+#endif /* of DEBUG */
+                       if ((name != NULL) && (fnode != NULL) && (ftype != NULL))
+                       {
+                               if(strcmp(filename, name) == 0)
+                               {
+                                       *ftype = type;
+                                       *fnode = fdiro;
+                                       return(1);
+                               }
+                       }
+                       else
+                       {
+                               if (fdiro->inode_read == 0)
+                               {
+                                       status = ext2fs_read_inode (diro->data, __le32_to_cpu (dirent.inode), &fdiro->inode);
+                                       if (status == 0)
+                                       {
+                                               free(fdiro);
+                                               return(0);
+                                       }
+                                       fdiro->inode_read = 1;
+                               }
+                               switch(type)
+                               {
+                               case FILETYPE_DIRECTORY:
+                                       printf("<DIR> ");
+                                       break;
+                               case FILETYPE_SYMLINK:
+                                       printf("<SYM> ");
+                                       break;
+                               case FILETYPE_REG:
+                                       printf("      ");
+                                       break;
+                               default:
+                                       printf("<???> ");
+                                       break;
+                               }
+                               printf("%10d %s\n", __le32_to_cpu(fdiro->inode.size), filename);
+                       }
+                       free(fdiro);
+               }
+               fpos += __le16_to_cpu (dirent.direntlen);
+       }
+       return(0);
+}
+
+
+static char *ext2fs_read_symlink
+(
+       ext2fs_node_t node
+       )
+{
+       char               *symlink;
+       struct ext2fs_node *diro = node;
+       int                 status;
+
+       if (!diro->inode_read)
+        {
+               status = ext2fs_read_inode (diro->data, diro->ino, &diro->inode);
+               if (status == 0)
+               {
+                       return(0);
+               }
+       }
+       symlink = malloc (__le32_to_cpu (diro->inode.size) + 1);
+       if (!symlink)
+        {
+               return(0);
+       }
+       /* If the filesize of the symlink is bigger than
+          60 the symlink is stored in a separate block,
+          otherwise it is stored in the inode.  */
+       if (__le32_to_cpu (diro->inode.size) <= 60)
+        {
+               strncpy (symlink, diro->inode.b.symlink, __le32_to_cpu (diro->inode.size));
+       }
+       else
+        {
+               status = ext2fs_read_file (diro, 0, __le32_to_cpu (diro->inode.size), symlink);
+               if (status == 0)
+               {
+                       free (symlink);
+                       return(0);
+               }
+       }
+       symlink[__le32_to_cpu (diro->inode.size)] = '\0';
+       return(symlink);
+}
+
+
+int ext2fs_find_file1
+(
+       const char    *currpath,
+       ext2fs_node_t  currroot,
+       ext2fs_node_t *currfound,
+       int           *foundtype
+       )
+{
+       char           fpath[strlen (currpath) + 1];
+       char          *name = fpath;
+       char          *next;
+       int            status;
+       int            type     = FILETYPE_DIRECTORY;
+       ext2fs_node_t  currnode = currroot;
+       ext2fs_node_t  oldnode  = currroot;
+
+       strncpy (fpath, currpath, strlen (currpath) + 1);
+
+       /* Remove all leading slashes.  */
+       while (*name == '/')
+        {
+               name++;
+        }
+       if (!*name)
+       {
+               *currfound = currnode;
+               return(1);
+       }
+
+       for (;;)
+       {
+               int found;
+
+               /* Extract the actual part from the pathname.  */
+               next = strchr (name, '/');
+               if (next)
+               {
+                       /* Remove all leading slashes.  */
+                       while (*next == '/')
+                       {
+                               *(next++) = '\0';
+                       }
+               }
+
+               /* At this point it is expected that the current node is a directory, check if this is true.  */
+               if (type != FILETYPE_DIRECTORY)
+               {
+                       ext2fs_free_node (currnode, currroot);
+                       return(0);
+               }
+
+               oldnode = currnode;
+
+               /* Iterate over the directory.  */
+               found = ext2fs_iterate_dir (currnode, name, &currnode, &type);
+               if (found == 0)
+               {
+                       return(0);
+               }
+               if (found == -1)
+               {
+                       break;
+               }
+
+               /* Read in the symlink and follow it.  */
+               if (type == FILETYPE_SYMLINK)
+               {
+                       char *symlink;
+
+                       /* Test if the symlink does not loop.  */
+                       if (++symlinknest == 8)
+                       {
+                               ext2fs_free_node (currnode, currroot);
+                               ext2fs_free_node (oldnode,  currroot);
+                               return(0);
+                       }
+
+                       symlink = ext2fs_read_symlink (currnode);
+                       ext2fs_free_node (currnode, currroot);
+
+                       if (!symlink)
+                       {
+                               ext2fs_free_node (oldnode, currroot);
+                               return(0);
+                       }
+#ifdef DEBUG
+                       printf("Got symlink >%s<\n",symlink);
+#endif /* of DEBUG */
+                       /* The symlink is an absolute path, go back to the root inode.  */
+                       if (symlink[0] == '/')
+                       {
+                               ext2fs_free_node (oldnode, currroot);
+                               oldnode = &ext2fs_root->diropen;
+                       }
+
+                       /* Lookup the node the symlink points to.  */
+                       status = ext2fs_find_file1 (symlink, oldnode, &currnode, &type);
+
+                       free (symlink);
+
+                       if (status == 0)
+                       {
+                               ext2fs_free_node (oldnode, currroot);
+                               return(0);
+                       }
+               }
+
+               ext2fs_free_node (oldnode, currroot);
+
+               /* Found the node!  */
+               if (!next || *next == '\0')
+               {
+                       *currfound = currnode;
+                       *foundtype = type;
+                       return(1);
+               }
+               name = next;
+       }
+       return(-1);
+}
+
+
+int ext2fs_find_file
+(
+       const char    *path,
+       ext2fs_node_t  rootnode,
+       ext2fs_node_t *foundnode,
+       int            expecttype
+       )
+{
+       int status;
+       int foundtype = FILETYPE_DIRECTORY;
+
+
+       symlinknest = 0;
+       if (!path || path[0] != '/')
+        {
+               return(0);
+       }
+
+       status = ext2fs_find_file1(path, rootnode, foundnode, &foundtype);
+       if (status == 0)
+        {
+               return(0);
+       }
+       /* Check if the node that was found was of the expected type.  */
+       if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
+        {
+               return(0);
+       }
+       else if ((expecttype == FILETYPE_DIRECTORY) && (foundtype != expecttype))
+        {
+               return(0);
+       }
+       return(1);
+}
+
+
+int ext2fs_ls
+(
+       char *dirname
+       )
+{
+       ext2fs_node_t dirnode;
+       int           status;
+
+       if (ext2fs_root == NULL)
+        {
+               return(0);
+       }
+
+       status = ext2fs_find_file(dirname, &ext2fs_root->diropen, &dirnode, FILETYPE_DIRECTORY);
+       if (status != 1)
+        {
+               printf("** Can not find directory. **\n");
+               return(1);
+        }
+       ext2fs_iterate_dir(dirnode, NULL, NULL, NULL);
+       ext2fs_free_node(dirnode, &ext2fs_root->diropen);
+       return(0);
+}
+
+
+int ext2fs_open
+(
+       char *filename
+       )
+{
+       ext2fs_node_t  fdiro = NULL;
+       int            status;
+       int            len;
+
+       if (ext2fs_root == NULL)
+        {
+               return(0);
+       }
+       ext2fs_file = NULL;
+       status      = ext2fs_find_file (filename, &ext2fs_root->diropen, &fdiro, FILETYPE_REG);
+       if (status == 0)
+        {
+               goto fail;
+       }
+       if (!fdiro->inode_read)
+        {
+               status = ext2fs_read_inode (fdiro->data, fdiro->ino, &fdiro->inode);
+               if (status == 0)
+               {
+                       goto fail;
+               }
+       }
+       len = __le32_to_cpu (fdiro->inode.size);
+       ext2fs_file = fdiro;
+       return(len);
+
+ fail:
+       ext2fs_free_node(fdiro, &ext2fs_root->diropen);
+       return(0);
+}
+
+
+int ext2fs_close
+(
+       void
+       )
+{
+       if ((ext2fs_file != NULL) && (ext2fs_root != NULL))
+        {
+               ext2fs_free_node(ext2fs_file, &ext2fs_root->diropen);
+               ext2fs_file = NULL;
+       }
+       if (ext2fs_root != NULL)
+       {
+               free(ext2fs_root);
+               ext2fs_root  = NULL;
+       }
+       if (indir1_block != NULL)
+        {
+               free(indir1_block);
+               indir1_block =  NULL;
+               indir1_size  =  0;
+               indir1_blkno =  -1;
+       }
+       if (indir2_block != NULL)
+        {
+               free(indir2_block);
+               indir2_block =  NULL;
+               indir2_size  =  0;
+               indir2_blkno =  -1;
+       }
+       return(0);
+}
+
+
+int ext2fs_read
+(
+       char     *buf,
+       unsigned  len
+       )
+{
+       int status;
+
+       if (ext2fs_root == NULL)
+        {
+               return(0);
+       }
+
+       if (ext2fs_file == NULL)
+        {
+               return(0);
+       }
+
+       status = ext2fs_read_file(ext2fs_file, 0, len, buf);
+       return(status);
+}
+
+
+int ext2fs_mount
+(
+       unsigned part_length
+       )
+{
+       struct ext2_data *data;
+       int               status;
+
+       data = malloc (sizeof (struct ext2_data));
+       if (!data)
+        {
+               return(0);
+       }
+       /* Read the superblock.  */
+       status = ext2fs_devread (1 * 2, 0, sizeof (struct ext2_sblock), (char *) &data->sblock);
+       if (status == 0)
+        {
+               goto fail;
+       }
+       /* Make sure this is an ext2 filesystem.  */
+       if (__le16_to_cpu (data->sblock.magic) != EXT2_MAGIC)
+        {
+               goto fail;
+       }
+       data->diropen.data       =  data;
+       data->diropen.ino        =  2;
+       data->diropen.inode_read =  1;
+       data->inode              = &data->diropen.inode;
+
+       status = ext2fs_read_inode (data, 2, data->inode);
+       if (status == 0)
+        {
+               goto fail;
+       }
+
+       ext2fs_root = data;
+
+       return(1);
+
+ fail:
+       printf("Failed to mount ext2 filesystem...\n");
+       free(data);
+       ext2fs_root = NULL;
+       return(0);
+}
+
+#endif /* CFG_CMD_EXT2FS */