From 2b9187127f6c1fe23adcbec3c390b9bf87779100 Mon Sep 17 00:00:00 2001 From: stroese Date: Thu, 16 Dec 2004 17:26:24 +0000 Subject: [PATCH] ext2fs support added --- fs/Makefile | 2 +- fs/ext2/Makefile | 48 +++ fs/ext2/dev.c | 142 +++++++ fs/ext2/ext2fs.c | 1004 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 1195 insertions(+), 1 deletion(-) create mode 100644 fs/ext2/Makefile create mode 100644 fs/ext2/dev.c create mode 100644 fs/ext2/ext2fs.c diff --git a/fs/Makefile b/fs/Makefile index c7507905d5..79cbdeaa7a 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -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 index 0000000000..3b193684f5 --- /dev/null +++ b/fs/ext2/Makefile @@ -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 index 0000000000..117a44984e --- /dev/null +++ b/fs/ext2/dev.c @@ -0,0 +1,142 @@ +/* + * (C) Copyright 2004 + * esd gmbh + * Reinhard Arlt + * + * based on code of fs/reiserfs/dev.c by + * + * (C) Copyright 2003 - 2004 + * Sysgo AG, , Pavel Bartusek + * + * 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 +#if (CONFIG_COMMANDS & CFG_CMD_EXT2) + +#include +#include + +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 index 0000000000..bae72a35a6 --- /dev/null +++ b/fs/ext2/ext2fs.c @@ -0,0 +1,1004 @@ +/* + * (C) Copyright 2004 + * esd gmbh + * Reinhard Arlt + * + * 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 + +#if (CONFIG_COMMANDS & CFG_CMD_EXT2) +#include +#include +#include + +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(" "); + break; + case FILETYPE_SYMLINK: + printf(" "); + 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 */ -- 2.39.5