diff options
Diffstat (limited to 'src/stream/fs/ext2fs.c')
| -rw-r--r-- | src/stream/fs/ext2fs.c | 793 |
1 files changed, 0 insertions, 793 deletions
diff --git a/src/stream/fs/ext2fs.c b/src/stream/fs/ext2fs.c deleted file mode 100644 index 9cf0bc6500..0000000000 --- a/src/stream/fs/ext2fs.c +++ /dev/null @@ -1,793 +0,0 @@ -/* - * GRUB -- GRand Unified Bootloader - * Copyright (C) 1999, 2001 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 <console/console.h> -#include <fs/fs.h> -#include <string.h> -#include <arch/byteorder.h> - -static int mapblock1, mapblock2; - -/* sizes are always in bytes, BLOCK values are always in DEV_BSIZE (sectors) */ -#define DEV_BSIZE 512 - -/* include/linux/fs.h */ -#define BLOCK_SIZE 1024 /* initial block size for superblock read */ -/* made up, defaults to 1 but can be passed via mount_opts */ -#define WHICH_SUPER 1 -/* kind of from fs/ext2/super.c */ -#define SBLOCK (WHICH_SUPER * BLOCK_SIZE / DEV_BSIZE) /* = 2 */ - -/* include/asm-i386/types.h */ -typedef __signed__ char __s8; -typedef unsigned char __u8; -typedef __signed__ short __s16; -typedef unsigned short __u16; -typedef __signed__ int __s32; -typedef unsigned int __u32; - -/* - * Constants relative to the data blocks, from ext2_fs.h - */ -#define EXT2_NDIR_BLOCKS 12 -#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS -#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) -#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) -#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) - -/* include/linux/ext2_fs.h */ -struct ext2_super_block - { - __u32 s_inodes_count; /* Inodes count */ - __u32 s_blocks_count; /* Blocks count */ - __u32 s_r_blocks_count; /* Reserved blocks count */ - __u32 s_free_blocks_count; /* Free blocks count */ - __u32 s_free_inodes_count; /* Free inodes count */ - __u32 s_first_data_block; /* First Data Block */ - __u32 s_log_block_size; /* Block size */ - __s32 s_log_frag_size; /* Fragment size */ - __u32 s_blocks_per_group; /* # Blocks per group */ - __u32 s_frags_per_group; /* # Fragments per group */ - __u32 s_inodes_per_group; /* # Inodes per group */ - __u32 s_mtime; /* Mount time */ - __u32 s_wtime; /* Write time */ - __u16 s_mnt_count; /* Mount count */ - __s16 s_max_mnt_count; /* Maximal mount count */ - __u16 s_magic; /* Magic signature */ - __u16 s_state; /* File system state */ - __u16 s_errors; /* Behaviour when detecting errors */ - __u16 s_pad; - __u32 s_lastcheck; /* time of last check */ - __u32 s_checkinterval; /* max. time between checks */ - __u32 s_creator_os; /* OS */ - __u32 s_rev_level; /* Revision level */ - __u16 s_def_resuid; /* Default uid for reserved blocks */ - __u16 s_def_resgid; /* Default gid for reserved blocks */ - __u32 s_reserved[235]; /* Padding to the end of the block */ - }; - -struct ext2_group_desc - { - __u32 bg_block_bitmap; /* Blocks bitmap block */ - __u32 bg_inode_bitmap; /* Inodes bitmap block */ - __u32 bg_inode_table; /* Inodes table block */ - __u16 bg_free_blocks_count; /* Free blocks count */ - __u16 bg_free_inodes_count; /* Free inodes count */ - __u16 bg_used_dirs_count; /* Directories count */ - __u16 bg_pad; - __u32 bg_reserved[3]; - }; - -struct ext2_inode - { - __u16 i_mode; /* File mode */ - __u16 i_uid; /* Owner Uid */ - __u32 i_size; /* 4: Size in bytes */ - __u32 i_atime; /* Access time */ - __u32 i_ctime; /* 12: Creation time */ - __u32 i_mtime; /* Modification time */ - __u32 i_dtime; /* 20: Deletion Time */ - __u16 i_gid; /* Group Id */ - __u16 i_links_count; /* 24: Links count */ - __u32 i_blocks; /* Blocks count */ - __u32 i_flags; /* 32: File flags */ - union - { - struct - { - __u32 l_i_reserved1; - } - linux1; - struct - { - __u32 h_i_translator; - } - hurd1; - struct - { - __u32 m_i_reserved1; - } - masix1; - } - osd1; /* OS dependent 1 */ - __u32 i_block[EXT2_N_BLOCKS]; /* 40: Pointers to blocks */ - __u32 i_version; /* File version (for NFS) */ - __u32 i_file_acl; /* File ACL */ - __u32 i_dir_acl; /* Directory ACL */ - __u32 i_faddr; /* Fragment address */ - union - { - struct - { - __u8 l_i_frag; /* Fragment number */ - __u8 l_i_fsize; /* Fragment size */ - __u16 i_pad1; - __u32 l_i_reserved2[2]; - } - linux2; - struct - { - __u8 h_i_frag; /* Fragment number */ - __u8 h_i_fsize; /* Fragment size */ - __u16 h_i_mode_high; - __u16 h_i_uid_high; - __u16 h_i_gid_high; - __u32 h_i_author; - } - hurd2; - struct - { - __u8 m_i_frag; /* Fragment number */ - __u8 m_i_fsize; /* Fragment size */ - __u16 m_pad1; - __u32 m_i_reserved2[2]; - } - masix2; - } - osd2; /* OS dependent 2 */ - }; - -/* linux/limits.h */ -#define NAME_MAX 255 /* # chars in a file name */ - -/* linux/posix_type.h */ -typedef long linux_off_t; - -/* linux/ext2fs.h */ -#define EXT2_NAME_LEN 255 -struct ext2_dir_entry - { - __u32 inode; /* Inode number */ - __u16 rec_len; /* Directory entry length */ - __u8 name_len; /* Name length */ - __u8 file_type; - char name[EXT2_NAME_LEN]; /* File name */ - }; - -/* linux/ext2fs.h */ -/* - * EXT2_DIR_PAD defines the directory entries boundaries - * - * NOTE: It must be a multiple of 4 - */ -#define EXT2_DIR_PAD 4 -#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) -#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ - ~EXT2_DIR_ROUND) - - -/* ext2/super.c */ -#define log2(n) ffz(~(n)) - -#define EXT2_SUPER_MAGIC 0xEF53 /* include/linux/ext2_fs.h */ -#define EXT2_ROOT_INO 2 /* include/linux/ext2_fs.h */ -#define PATH_MAX 1024 /* include/linux/limits.h */ -#define MAX_LINK_COUNT 5 /* number of symbolic links to follow */ - -/* made up, these are pointers into FSYS_BUF */ -/* read once, always stays there: */ -#define SUPERBLOCK \ - ((struct ext2_super_block *)(FSYS_BUF)) -#define GROUP_DESC \ - ((struct ext2_group_desc *) \ - ((int)SUPERBLOCK + sizeof(struct ext2_super_block))) -#define INODE \ - ((struct ext2_inode *)((int)GROUP_DESC + EXT2_BLOCK_SIZE(SUPERBLOCK))) -#define DATABLOCK1 \ - ((int)((int)INODE + sizeof(struct ext2_inode))) -#define DATABLOCK2 \ - ((int)((int)DATABLOCK1 + EXT2_BLOCK_SIZE(SUPERBLOCK))) - -/* linux/ext2_fs.h */ -#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32)) -#define EXT2_ADDR_PER_BLOCK_BITS(s) (log2(EXT2_ADDR_PER_BLOCK(s))) - -/* linux/ext2_fs.h */ -#define EXT2_BLOCK_SIZE_BITS(s) (le32_to_cpu((s)->s_log_block_size) + 10) -/* kind of from ext2/super.c */ -#define EXT2_BLOCK_SIZE(s) (1 << EXT2_BLOCK_SIZE_BITS(s)) -/* linux/ext2fs.h */ -#define EXT2_DESC_PER_BLOCK(s) \ - (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc)) -/* linux/stat.h */ -#define S_IFMT 00170000 -#define S_IFLNK 0120000 -#define S_IFREG 0100000 -#define S_IFDIR 0040000 -#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK) -#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG) -#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR) - -/* include/asm-i386/bitops.h */ -/* - * ffz = Find First Zero in word. Undefined if no zero exists, - * so code should check against ~0UL first.. - */ -#ifdef __i386 -static __inline__ unsigned long -ffz (unsigned long word) -{ - __asm__ ("bsfl %1,%0" -: "=r" (word) -: "r" (~word)); - return word; -} -#else /* !PPC */ -static __inline__ unsigned long - __ilog2(unsigned long x) -{ - unsigned long lz; - - asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x)); - return 31 - lz; -} -static __inline__ unsigned long -ffz(unsigned long x) -{ - if ((x = ~x) == 0) - return 32; - return __ilog2(x & -x); -} -#endif - -/* check filesystem types and read superblock into memory buffer */ -int -ext2fs_mount (void) -{ - int retval = 1; - - if ((((current_drive & 0x80) || (current_slice != 0)) - && (current_slice != PC_SLICE_TYPE_EXT2FS) - && (current_slice != PC_SLICE_TYPE_LINUX_RAID) - && (! IS_PC_SLICE_TYPE_BSD_WITH_FS (current_slice, FS_EXT2FS)) - && (! IS_PC_SLICE_TYPE_BSD_WITH_FS (current_slice, FS_OTHER))) - || part_length < (SBLOCK + (sizeof (struct ext2_super_block) / DEV_BSIZE)) - || !devread (SBLOCK, 0, sizeof (struct ext2_super_block), - (char *) SUPERBLOCK) - || le16_to_cpu(SUPERBLOCK->s_magic) != EXT2_SUPER_MAGIC) - retval = 0; - - return retval; -} - -/* Takes a file system block number and reads it into BUFFER. */ -static int -ext2_rdfsb (int fsblock, int buffer) -{ -#ifdef E2DEBUG - printk_debug ("fsblock %d buffer %d\n", fsblock, buffer); -#endif /* E2DEBUG */ - return devread (fsblock * (EXT2_BLOCK_SIZE (SUPERBLOCK) / DEV_BSIZE), 0, - EXT2_BLOCK_SIZE (SUPERBLOCK), (char *) buffer); -} - -/* from - ext2/inode.c:ext2_bmap() -*/ -/* Maps LOGICAL_BLOCK (the file offset divided by the blocksize) into - a physical block (the location in the file system) via an inode. */ -static int -ext2fs_block_map (int logical_block) -{ - -#ifdef E2DEBUG - unsigned char *i; - for (i = (unsigned char *) INODE; - i < ((unsigned char *) INODE + sizeof (struct ext2_inode)); - i++) - { - printk_debug ("%c", "0123456789abcdef"[*i >> 4]); - printk_debug ("%c", "0123456789abcdef"[*i % 16]); - if (!((i + 1 - (unsigned char *) INODE) % 16)) - { - printk_debug ("\n"); - } - else - { - printk_debug (" "); - } - } - printk_debug ("logical block %d\n", logical_block); -#endif /* E2DEBUG */ - - /* if it is directly pointed to by the inode, return that physical addr */ - if (logical_block < EXT2_NDIR_BLOCKS) - { -#ifdef E2DEBUG - printk_debug ("returning %d\n", (unsigned char *) (le32_to_cpu(INODE->i_block[logical_block]))); - printk_debug ("returning %d\n", le32_to_cpu(INODE->i_block[logical_block])); -#endif /* E2DEBUG */ - return le32_to_cpu(INODE->i_block[logical_block]); - } - /* else */ - logical_block -= EXT2_NDIR_BLOCKS; - /* try the indirect block */ - if (logical_block < EXT2_ADDR_PER_BLOCK (SUPERBLOCK)) - { - if (mapblock1 != 1 - && !ext2_rdfsb (le32_to_cpu(INODE->i_block[EXT2_IND_BLOCK]), DATABLOCK1)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - mapblock1 = 1; - return le32_to_cpu(((__u32 *) DATABLOCK1)[logical_block]); - } - /* else */ - logical_block -= EXT2_ADDR_PER_BLOCK (SUPERBLOCK); - /* now try the double indirect block */ - if (logical_block < (1 << (EXT2_ADDR_PER_BLOCK_BITS (SUPERBLOCK) * 2))) - { - int bnum; - if (mapblock1 != 2 - && !ext2_rdfsb (le32_to_cpu(INODE->i_block[EXT2_DIND_BLOCK]), DATABLOCK1)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - mapblock1 = 2; - if ((bnum = le32_to_cpu(((__u32 *) DATABLOCK1) - [logical_block >> EXT2_ADDR_PER_BLOCK_BITS (SUPERBLOCK)])) - != mapblock2 - && !ext2_rdfsb (bnum, DATABLOCK2)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - mapblock2 = bnum; - return le32_to_cpu(((__u32 *) DATABLOCK2) - [logical_block & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)]); - } - /* else */ - mapblock2 = -1; - logical_block -= (1 << (EXT2_ADDR_PER_BLOCK_BITS (SUPERBLOCK) * 2)); - if (mapblock1 != 3 - && !ext2_rdfsb (le32_to_cpu(INODE->i_block[EXT2_TIND_BLOCK]), DATABLOCK1)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - mapblock1 = 3; - if (!ext2_rdfsb (le32_to_cpu(((__u32 *) DATABLOCK1) - [logical_block >> (EXT2_ADDR_PER_BLOCK_BITS (SUPERBLOCK) - * 2)]), - DATABLOCK2)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - if (!ext2_rdfsb (le32_to_cpu(((__u32 *) DATABLOCK2) - [(logical_block >> EXT2_ADDR_PER_BLOCK_BITS (SUPERBLOCK)) - & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)]), - DATABLOCK2)) - { - errnum = ERR_FSYS_CORRUPT; - return -1; - } - return le32_to_cpu(((__u32 *) DATABLOCK2) - [logical_block & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)]); -} - -/* preconditions: all preconds of ext2fs_block_map */ -int -ext2fs_read (char *buf, int len) -{ - int logical_block; - int offset; - int map; - int ret = 0; - int size = 0; - -#ifdef E2DEBUG - static char hexdigit[] = "0123456789abcdef"; - unsigned char *i; - for (i = (unsigned char *) INODE; - i < ((unsigned char *) INODE + sizeof (struct ext2_inode)); - i++) - { - printk_debug ("%c", hexdigit[*i >> 4]); - printk_debug ("%c", hexdigit[*i % 16]); - if (!((i + 1 - (unsigned char *) INODE) % 16)) - { - printk_debug ("\n"); - } - else - { - printk_debug (" "); - } - } -#endif /* E2DEBUG */ - while (len > 0) - { - /* find the (logical) block component of our location */ - logical_block = filepos >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK); - offset = filepos & (EXT2_BLOCK_SIZE (SUPERBLOCK) - 1); - map = ext2fs_block_map (logical_block); -#ifdef E2DEBUG - printk_debug ("map=%d\n", map); -#endif /* E2DEBUG */ - if (map < 0) - break; - - size = EXT2_BLOCK_SIZE (SUPERBLOCK); - size -= offset; - if (size > len) - size = len; - - disk_read_func = disk_read_hook; - - devread (map * (EXT2_BLOCK_SIZE (SUPERBLOCK) / DEV_BSIZE), - offset, size, buf); - - disk_read_func = 0; - - buf += size; - len -= size; - filepos += size; - ret += size; - } - - if (errnum) - ret = 0; - - return ret; -} - - -/* Based on: - def_blk_fops points to - blkdev_open, which calls (I think): - sys_open() - do_open() - open_namei() - dir_namei() which accesses current->fs->root - fs->root was set during original mount: - (something)... which calls (I think): - ext2_read_super() - iget() - __iget() - read_inode() - ext2_read_inode() - uses desc_per_block_bits, which is set in ext2_read_super() - also uses group descriptors loaded during ext2_read_super() - lookup() - ext2_lookup() - ext2_find_entry() - ext2_getblk() - -*/ - -/* preconditions: ext2fs_mount already executed, therefore supblk in buffer - * known as SUPERBLOCK - * returns: 0 if error, nonzero iff we were able to find the file successfully - * postconditions: on a nonzero return, buffer known as INODE contains the - * inode of the file we were trying to look up - * side effects: messes up GROUP_DESC buffer area - */ -int -ext2fs_dir (char *dirname) -{ - int current_ino = EXT2_ROOT_INO; /* start at the root */ - int updir_ino = current_ino; /* the parent of the current directory */ - int group_id; /* which group the inode is in */ - int group_desc; /* fs pointer to that group */ - int desc; /* index within that group */ - int ino_blk; /* fs pointer of the inode's information */ - int str_chk = 0; /* used to hold the results of a string compare */ - struct ext2_group_desc *gdp; - struct ext2_inode *raw_inode; /* inode info corresponding to current_ino */ - - char linkbuf[PATH_MAX]; /* buffer for following symbolic links */ - int link_count = 0; - - char *rest; - char ch; /* temp char holder */ - - int off; /* offset within block of directory entry (off mod blocksize) */ - int loc; /* location within a directory */ - int blk; /* which data blk within dir entry (off div blocksize) */ - long map; /* fs pointer of a particular block from dir entry */ - struct ext2_dir_entry *dp; /* pointer to directory entry */ -#ifdef E2DEBUG - unsigned char *i; -#endif /* E2DEBUG */ - - /* loop invariants: - current_ino = inode to lookup - dirname = pointer to filename component we are cur looking up within - the directory known pointed to by current_ino (if any) - */ - - while (1) - { -#ifdef E2DEBUG - printk_debug ("inode %d\n", current_ino); - printk_debug ("dirname=%s\n", dirname); -#endif /* E2DEBUG */ - - /* look up an inode */ - group_id = (current_ino - 1) / le32_to_cpu(SUPERBLOCK->s_inodes_per_group); - group_desc = group_id >> log2 (EXT2_DESC_PER_BLOCK (SUPERBLOCK)); - desc = group_id & (EXT2_DESC_PER_BLOCK (SUPERBLOCK) - 1); -#ifdef E2DEBUG - printk_debug ("ipg=%d, dpb=%d\n", le32_to_cpu(SUPERBLOCK->s_inodes_per_group), - EXT2_DESC_PER_BLOCK (SUPERBLOCK)); - printk_debug ("group_id=%d group_desc=%d desc=%d\n", group_id, group_desc, desc); -#endif /* E2DEBUG */ - if (!ext2_rdfsb ( - (WHICH_SUPER + group_desc + le32_to_cpu(SUPERBLOCK->s_first_data_block)), - (int) GROUP_DESC)) - { - return 0; - } - gdp = GROUP_DESC; - ino_blk = le32_to_cpu(gdp[desc].bg_inode_table) + - (((current_ino - 1) % le32_to_cpu(SUPERBLOCK->s_inodes_per_group)) - >> log2 (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode))); -#ifdef E2DEBUG - printk_debug ("inode table fsblock=%d\n", ino_blk); -#endif /* E2DEBUG */ - if (!ext2_rdfsb (ino_blk, (int) INODE)) - { - return 0; - } - - /* reset indirect blocks! */ - mapblock2 = mapblock1 = -1; - - raw_inode = INODE + - ((current_ino - 1) - & (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode) - 1)); -#ifdef E2DEBUG - printk_debug ("ipb=%d, sizeof(inode)=%d\n", - (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode)), - sizeof (struct ext2_inode)); - printk_debug ("inode=%x, raw_inode=%x\n", INODE, raw_inode); - printk_debug ("offset into inode table block=%d\n", (int) raw_inode - (int) INODE); - for (i = (unsigned char *) INODE; i <= (unsigned char *) raw_inode; - i++) - { - printk_debug ("%c", "0123456789abcdef"[*i >> 4]); - printk_debug ("%c", "0123456789abcdef"[*i % 16]); - if (!((i + 1 - (unsigned char *) INODE) % 16)) - { - printk_debug ("\n"); - } - else - { - printk_debug (" "); - } - } - printk_debug ("first word=%x\n", *((int *) raw_inode)); -#endif /* E2DEBUG */ - - /* copy inode to fixed location */ - memmove ((void *) INODE, (void *) raw_inode, sizeof (struct ext2_inode)); - -#ifdef E2DEBUG - printk_debug ("first word=%x\n", *((int *) INODE)); -#endif /* E2DEBUG */ - - /* If we've got a symbolic link, then chase it. */ - if (S_ISLNK (le16_to_cpu(INODE->i_mode))) - { - int len; - if (++link_count > MAX_LINK_COUNT) - { - errnum = ERR_SYMLINK_LOOP; - return 0; - } - - /* Find out how long our remaining name is. */ - len = 0; - while (dirname[len] && !isspace (dirname[len])) - len++; - - /* Get the symlink size. */ - filemax = le32_to_cpu(INODE->i_size); - if (filemax + len > sizeof (linkbuf) - 2) - { - errnum = ERR_FILELENGTH; - return 0; - } - - if (len) - { - /* Copy the remaining name to the end of the symlink data. - Note that DIRNAME and LINKBUF may overlap! */ - memmove (linkbuf + filemax, dirname, len); - } - linkbuf[filemax + len] = '\0'; - - /* Read the symlink data. */ - if (le32_to_cpu(INODE->i_blocks)) - { - /* Read the necessary blocks, and reset the file pointer. */ - len = file_read (linkbuf, filemax); - filepos = 0; - if (!len) - return 0; - } - else - { - /* Copy the data directly from the inode. */ - len = filemax; - memmove (linkbuf, (char *) INODE->i_block, len); - } - -#ifdef E2DEBUG - printk_debug ("symlink=%s\n", linkbuf); -#endif - - dirname = linkbuf; - if (*dirname == '/') - { - /* It's an absolute link, so look it up in root. */ - current_ino = EXT2_ROOT_INO; - updir_ino = current_ino; - } - else - { - /* Relative, so look it up in our parent directory. */ - current_ino = updir_ino; - } - - /* Try again using the new name. */ - continue; - } - - /* if end of filename, INODE points to the file's inode */ - if (!*dirname || isspace (*dirname)) - { - if (!S_ISREG (le16_to_cpu(INODE->i_mode))) - { - errnum = ERR_BAD_FILETYPE; - return 0; - } - - filemax = le32_to_cpu(INODE->i_size); - return 1; - } - - /* else we have to traverse a directory */ - updir_ino = current_ino; - - /* skip over slashes */ - while (*dirname == '/') - dirname++; - - /* if this isn't a directory of sufficient size to hold our file, abort */ - if (!(le32_to_cpu(INODE->i_size)) || !S_ISDIR (le16_to_cpu(INODE->i_mode))) - { - errnum = ERR_BAD_FILETYPE; - return 0; - } - - /* skip to next slash or end of filename (space) */ - for (rest = dirname; (ch = *rest) && !isspace (ch) && ch != '/'; - rest++); - - /* look through this directory and find the next filename component */ - /* invariant: rest points to slash after the next filename component */ - *rest = 0; - loc = 0; - - do - { - -#ifdef E2DEBUG - printk_debug ("dirname=%s, rest=%s, loc=%d\n", dirname, rest, loc); -#endif /* E2DEBUG */ - - /* if our location/byte offset into the directory exceeds the size, - give up */ - if (loc >= le32_to_cpu(INODE->i_size)) - { - if (print_possibilities < 0) - { -# if 0 - putchar ('\n'); -# endif - } - else - { - errnum = ERR_FILE_NOT_FOUND; - *rest = ch; - } - return (print_possibilities < 0); - } - - /* else, find the (logical) block component of our location */ - blk = loc >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK); - - /* we know which logical block of the directory entry we are looking - for, now we have to translate that to the physical (fs) block on - the disk */ - map = ext2fs_block_map (blk); -#ifdef E2DEBUG - printk_debug ("fs block=%d\n", map); -#endif /* E2DEBUG */ - mapblock2 = -1; - if ((map < 0) || !ext2_rdfsb (map, DATABLOCK2)) - { - errnum = ERR_FSYS_CORRUPT; - *rest = ch; - return 0; - } - off = loc & (EXT2_BLOCK_SIZE (SUPERBLOCK) - 1); - dp = (struct ext2_dir_entry *) (DATABLOCK2 + off); - /* advance loc prematurely to next on-disk directory entry */ - loc += le16_to_cpu(dp->rec_len); - - /* NOTE: ext2fs filenames are NOT null-terminated */ - -#ifdef E2DEBUG - printk_debug ("directory entry ino=%d\n", le32_to_cpu(dp->inode)); - if (le32_to_cpu(dp->inode)) - printk_debug ("entry=%s\n", dp->name); -#endif /* E2DEBUG */ - - if (le32_to_cpu(dp->inode)) - { - int saved_c = dp->name[dp->name_len]; - - dp->name[dp->name_len] = 0; - str_chk = substring (dirname, dp->name); - -# ifndef STAGE1_5 - if (print_possibilities && ch != '/' - && (!*dirname || str_chk <= 0)) - { - if (print_possibilities > 0) - print_possibilities = -print_possibilities; - print_a_completion (dp->name); - } -# endif - - dp->name[dp->name_len] = saved_c; - } - - } - while (!le32_to_cpu(dp->inode) || (str_chk || (print_possibilities && ch != '/'))); - - current_ino = le32_to_cpu(dp->inode); - *(dirname = rest) = ch; - } - /* never get here */ -} |