diff options
Diffstat (limited to 'e2fsprogs/old_e2fsprogs/ext2fs/inode.c')
| -rw-r--r-- | e2fsprogs/old_e2fsprogs/ext2fs/inode.c | 768 |
1 files changed, 768 insertions, 0 deletions
diff --git a/e2fsprogs/old_e2fsprogs/ext2fs/inode.c b/e2fsprogs/old_e2fsprogs/ext2fs/inode.c new file mode 100644 index 0000000..2ff9fe6 --- /dev/null +++ b/e2fsprogs/old_e2fsprogs/ext2fs/inode.c @@ -0,0 +1,768 @@ +/* vi: set sw=4 ts=4: */ +/* + * inode.c --- utility routines to read and write inodes + * + * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o. + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + */ + +#include <stdio.h> +#include <string.h> +#if HAVE_UNISTD_H +#include <unistd.h> +#endif +#if HAVE_ERRNO_H +#include <errno.h> +#endif +#if HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#if HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif + +#include "ext2_fs.h" +#include "ext2fsP.h" +#include "e2image.h" + +struct ext2_struct_inode_scan { + errcode_t magic; + ext2_filsys fs; + ext2_ino_t current_inode; + blk_t current_block; + dgrp_t current_group; + ext2_ino_t inodes_left; + blk_t blocks_left; + dgrp_t groups_left; + blk_t inode_buffer_blocks; + char * inode_buffer; + int inode_size; + char * ptr; + int bytes_left; + char *temp_buffer; + errcode_t (*done_group)(ext2_filsys fs, + dgrp_t group, + void * priv_data); + void * done_group_data; + int bad_block_ptr; + int scan_flags; + int reserved[6]; +}; + +/* + * This routine flushes the icache, if it exists. + */ +errcode_t ext2fs_flush_icache(ext2_filsys fs) +{ + int i; + + if (!fs->icache) + return 0; + + for (i=0; i < fs->icache->cache_size; i++) + fs->icache->cache[i].ino = 0; + + fs->icache->buffer_blk = 0; + return 0; +} + +static errcode_t create_icache(ext2_filsys fs) +{ + errcode_t retval; + + if (fs->icache) + return 0; + retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache); + if (retval) + return retval; + + memset(fs->icache, 0, sizeof(struct ext2_inode_cache)); + retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer); + if (retval) { + ext2fs_free_mem(&fs->icache); + return retval; + } + fs->icache->buffer_blk = 0; + fs->icache->cache_last = -1; + fs->icache->cache_size = 4; + fs->icache->refcount = 1; + retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache_ent) + * fs->icache->cache_size, + &fs->icache->cache); + if (retval) { + ext2fs_free_mem(&fs->icache->buffer); + ext2fs_free_mem(&fs->icache); + return retval; + } + ext2fs_flush_icache(fs); + return 0; +} + +errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks, + ext2_inode_scan *ret_scan) +{ + ext2_inode_scan scan; + errcode_t retval; + errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks); + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + /* + * If fs->badblocks isn't set, then set it --- since the inode + * scanning functions require it. + */ + if (fs->badblocks == 0) { + /* + * Temporarly save fs->get_blocks and set it to zero, + * for compatibility with old e2fsck's. + */ + save_get_blocks = fs->get_blocks; + fs->get_blocks = 0; + retval = ext2fs_read_bb_inode(fs, &fs->badblocks); + if (retval) { + ext2fs_badblocks_list_free(fs->badblocks); + fs->badblocks = 0; + } + fs->get_blocks = save_get_blocks; + } + + retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan); + if (retval) + return retval; + memset(scan, 0, sizeof(struct ext2_struct_inode_scan)); + + scan->magic = EXT2_ET_MAGIC_INODE_SCAN; + scan->fs = fs; + scan->inode_size = EXT2_INODE_SIZE(fs->super); + scan->bytes_left = 0; + scan->current_group = 0; + scan->groups_left = fs->group_desc_count - 1; + scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8; + scan->current_block = scan->fs-> + group_desc[scan->current_group].bg_inode_table; + scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); + scan->blocks_left = scan->fs->inode_blocks_per_group; + retval = ext2fs_get_mem((size_t) (scan->inode_buffer_blocks * + fs->blocksize), + &scan->inode_buffer); + scan->done_group = 0; + scan->done_group_data = 0; + scan->bad_block_ptr = 0; + if (retval) { + ext2fs_free_mem(&scan); + return retval; + } + retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer); + if (retval) { + ext2fs_free_mem(&scan->inode_buffer); + ext2fs_free_mem(&scan); + return retval; + } + if (scan->fs->badblocks && scan->fs->badblocks->num) + scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS; + *ret_scan = scan; + return 0; +} + +void ext2fs_close_inode_scan(ext2_inode_scan scan) +{ + if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) + return; + + ext2fs_free_mem(&scan->inode_buffer); + scan->inode_buffer = NULL; + ext2fs_free_mem(&scan->temp_buffer); + scan->temp_buffer = NULL; + ext2fs_free_mem(&scan); + return; +} + +void ext2fs_set_inode_callback(ext2_inode_scan scan, + errcode_t (*done_group)(ext2_filsys fs, + dgrp_t group, + void * priv_data), + void *done_group_data) +{ + if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) + return; + + scan->done_group = done_group; + scan->done_group_data = done_group_data; +} + +int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags, + int clear_flags) +{ + int old_flags; + + if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) + return 0; + + old_flags = scan->scan_flags; + scan->scan_flags &= ~clear_flags; + scan->scan_flags |= set_flags; + return old_flags; +} + +/* + * This function is called by ext2fs_get_next_inode when it needs to + * get ready to read in a new blockgroup. + */ +static errcode_t get_next_blockgroup(ext2_inode_scan scan) +{ + scan->current_group++; + scan->groups_left--; + + scan->current_block = scan->fs-> + group_desc[scan->current_group].bg_inode_table; + + scan->current_inode = scan->current_group * + EXT2_INODES_PER_GROUP(scan->fs->super); + + scan->bytes_left = 0; + scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); + scan->blocks_left = scan->fs->inode_blocks_per_group; + return 0; +} + +errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan, + int group) +{ + scan->current_group = group - 1; + scan->groups_left = scan->fs->group_desc_count - group; + return get_next_blockgroup(scan); +} + +/* + * This function is called by get_next_blocks() to check for bad + * blocks in the inode table. + * + * This function assumes that badblocks_list->list is sorted in + * increasing order. + */ +static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan, + blk_t *num_blocks) +{ + blk_t blk = scan->current_block; + badblocks_list bb = scan->fs->badblocks; + + /* + * If the inode table is missing, then obviously there are no + * bad blocks. :-) + */ + if (blk == 0) + return 0; + + /* + * If the current block is greater than the bad block listed + * in the bad block list, then advance the pointer until this + * is no longer the case. If we run out of bad blocks, then + * we don't need to do any more checking! + */ + while (blk > bb->list[scan->bad_block_ptr]) { + if (++scan->bad_block_ptr >= bb->num) { + scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; + return 0; + } + } + + /* + * If the current block is equal to the bad block listed in + * the bad block list, then handle that one block specially. + * (We could try to handle runs of bad blocks, but that + * only increases CPU efficiency by a small amount, at the + * expense of a huge expense of code complexity, and for an + * uncommon case at that.) + */ + if (blk == bb->list[scan->bad_block_ptr]) { + scan->scan_flags |= EXT2_SF_BAD_INODE_BLK; + *num_blocks = 1; + if (++scan->bad_block_ptr >= bb->num) + scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; + return 0; + } + + /* + * If there is a bad block in the range that we're about to + * read in, adjust the number of blocks to read so that we we + * don't read in the bad block. (Then the next block to read + * will be the bad block, which is handled in the above case.) + */ + if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr]) + *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk); + + return 0; +} + +/* + * This function is called by ext2fs_get_next_inode when it needs to + * read in more blocks from the current blockgroup's inode table. + */ +static errcode_t get_next_blocks(ext2_inode_scan scan) +{ + blk_t num_blocks; + errcode_t retval; + + /* + * Figure out how many blocks to read; we read at most + * inode_buffer_blocks, and perhaps less if there aren't that + * many blocks left to read. + */ + num_blocks = scan->inode_buffer_blocks; + if (num_blocks > scan->blocks_left) + num_blocks = scan->blocks_left; + + /* + * If the past block "read" was a bad block, then mark the + * left-over extra bytes as also being bad. + */ + if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) { + if (scan->bytes_left) + scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES; + scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK; + } + + /* + * Do inode bad block processing, if necessary. + */ + if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) { + retval = check_for_inode_bad_blocks(scan, &num_blocks); + if (retval) + return retval; + } + + if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) || + (scan->current_block == 0)) { + memset(scan->inode_buffer, 0, + (size_t) num_blocks * scan->fs->blocksize); + } else { + retval = io_channel_read_blk(scan->fs->io, + scan->current_block, + (int) num_blocks, + scan->inode_buffer); + if (retval) + return EXT2_ET_NEXT_INODE_READ; + } + scan->ptr = scan->inode_buffer; + scan->bytes_left = num_blocks * scan->fs->blocksize; + + scan->blocks_left -= num_blocks; + if (scan->current_block) + scan->current_block += num_blocks; + return 0; +} + +errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, + struct ext2_inode *inode, int bufsize) +{ + errcode_t retval; + int extra_bytes = 0; + + EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN); + + /* + * Do we need to start reading a new block group? + */ + if (scan->inodes_left <= 0) { + force_new_group: + if (scan->done_group) { + retval = (scan->done_group) + (scan->fs, scan->current_group, + scan->done_group_data); + if (retval) + return retval; + } + if (scan->groups_left <= 0) { + *ino = 0; + return 0; + } + retval = get_next_blockgroup(scan); + if (retval) + return retval; + } + /* + * This is done outside the above if statement so that the + * check can be done for block group #0. + */ + if (scan->current_block == 0) { + if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) { + goto force_new_group; + } else + return EXT2_ET_MISSING_INODE_TABLE; + } + + + /* + * Have we run out of space in the inode buffer? If so, we + * need to read in more blocks. + */ + if (scan->bytes_left < scan->inode_size) { + memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left); + extra_bytes = scan->bytes_left; + + retval = get_next_blocks(scan); + if (retval) + return retval; +#if 0 + /* + * XXX test Need check for used inode somehow. + * (Note: this is hard.) + */ + if (is_empty_scan(scan)) + goto force_new_group; +#endif + } + + retval = 0; + if (extra_bytes) { + memcpy(scan->temp_buffer+extra_bytes, scan->ptr, + scan->inode_size - extra_bytes); + scan->ptr += scan->inode_size - extra_bytes; + scan->bytes_left -= scan->inode_size - extra_bytes; + +#if BB_BIG_ENDIAN + if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) || + (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) + ext2fs_swap_inode_full(scan->fs, + (struct ext2_inode_large *) inode, + (struct ext2_inode_large *) scan->temp_buffer, + 0, bufsize); + else +#endif + *inode = *((struct ext2_inode *) scan->temp_buffer); + if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES) + retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; + scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES; + } else { +#if BB_BIG_ENDIAN + if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) || + (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) + ext2fs_swap_inode_full(scan->fs, + (struct ext2_inode_large *) inode, + (struct ext2_inode_large *) scan->ptr, + 0, bufsize); + else +#endif + memcpy(inode, scan->ptr, bufsize); + scan->ptr += scan->inode_size; + scan->bytes_left -= scan->inode_size; + if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) + retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; + } + + scan->inodes_left--; + scan->current_inode++; + *ino = scan->current_inode; + return retval; +} + +errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino, + struct ext2_inode *inode) +{ + return ext2fs_get_next_inode_full(scan, ino, inode, + sizeof(struct ext2_inode)); +} + +/* + * Functions to read and write a single inode. + */ +errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode * inode, int bufsize) +{ + unsigned long group, block, block_nr, offset; + char *ptr; + errcode_t retval; + int clen, i, inodes_per_block, length; + io_channel io; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + /* Check to see if user has an override function */ + if (fs->read_inode) { + retval = (fs->read_inode)(fs, ino, inode); + if (retval != EXT2_ET_CALLBACK_NOTHANDLED) + return retval; + } + /* Create inode cache if not present */ + if (!fs->icache) { + retval = create_icache(fs); + if (retval) + return retval; + } + /* Check to see if it's in the inode cache */ + if (bufsize == sizeof(struct ext2_inode)) { + /* only old good inode can be retrieve from the cache */ + for (i=0; i < fs->icache->cache_size; i++) { + if (fs->icache->cache[i].ino == ino) { + *inode = fs->icache->cache[i].inode; + return 0; + } + } + } + if ((ino == 0) || (ino > fs->super->s_inodes_count)) + return EXT2_ET_BAD_INODE_NUM; + if (fs->flags & EXT2_FLAG_IMAGE_FILE) { + inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); + block_nr = fs->image_header->offset_inode / fs->blocksize; + block_nr += (ino - 1) / inodes_per_block; + offset = ((ino - 1) % inodes_per_block) * + EXT2_INODE_SIZE(fs->super); + io = fs->image_io; + } else { + group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); + offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * + EXT2_INODE_SIZE(fs->super); + block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); + if (!fs->group_desc[(unsigned)group].bg_inode_table) + return EXT2_ET_MISSING_INODE_TABLE; + block_nr = fs->group_desc[(unsigned)group].bg_inode_table + + block; + io = fs->io; + } + offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); + + length = EXT2_INODE_SIZE(fs->super); + if (bufsize < length) + length = bufsize; + + ptr = (char *) inode; + while (length) { + clen = length; + if ((offset + length) > fs->blocksize) + clen = fs->blocksize - offset; + + if (block_nr != fs->icache->buffer_blk) { + retval = io_channel_read_blk(io, block_nr, 1, + fs->icache->buffer); + if (retval) + return retval; + fs->icache->buffer_blk = block_nr; + } + + memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset, + clen); + + offset = 0; + length -= clen; + ptr += clen; + block_nr++; + } + +#if BB_BIG_ENDIAN + if ((fs->flags & EXT2_FLAG_SWAP_BYTES) || + (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)) + ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode, + (struct ext2_inode_large *) inode, + 0, length); +#endif + + /* Update the inode cache */ + fs->icache->cache_last = (fs->icache->cache_last + 1) % + fs->icache->cache_size; + fs->icache->cache[fs->icache->cache_last].ino = ino; + fs->icache->cache[fs->icache->cache_last].inode = *inode; + + return 0; +} + +errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode * inode) +{ + return ext2fs_read_inode_full(fs, ino, inode, + sizeof(struct ext2_inode)); +} + +errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode * inode, int bufsize) +{ + unsigned long group, block, block_nr, offset; + errcode_t retval = 0; + struct ext2_inode_large temp_inode, *w_inode; + char *ptr; + int clen, i, length; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + /* Check to see if user provided an override function */ + if (fs->write_inode) { + retval = (fs->write_inode)(fs, ino, inode); + if (retval != EXT2_ET_CALLBACK_NOTHANDLED) + return retval; + } + + /* Check to see if the inode cache needs to be updated */ + if (fs->icache) { + for (i=0; i < fs->icache->cache_size; i++) { + if (fs->icache->cache[i].ino == ino) { + fs->icache->cache[i].inode = *inode; + break; + } + } + } else { + retval = create_icache(fs); + if (retval) + return retval; + } + + if (!(fs->flags & EXT2_FLAG_RW)) + return EXT2_ET_RO_FILSYS; + + if ((ino == 0) || (ino > fs->super->s_inodes_count)) + return EXT2_ET_BAD_INODE_NUM; + + length = bufsize; + if (length < EXT2_INODE_SIZE(fs->super)) + length = EXT2_INODE_SIZE(fs->super); + + if (length > (int) sizeof(struct ext2_inode_large)) { + w_inode = xmalloc(length); + } else + w_inode = &temp_inode; + memset(w_inode, 0, length); + +#if BB_BIG_ENDIAN + if ((fs->flags & EXT2_FLAG_SWAP_BYTES) || + (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)) + ext2fs_swap_inode_full(fs, w_inode, + (struct ext2_inode_large *) inode, + 1, bufsize); + else +#endif + memcpy(w_inode, inode, bufsize); + + group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); + offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * + EXT2_INODE_SIZE(fs->super); + block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); + if (!fs->group_desc[(unsigned) group].bg_inode_table) + return EXT2_ET_MISSING_INODE_TABLE; + block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block; + + offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); + + length = EXT2_INODE_SIZE(fs->super); + if (length > bufsize) + length = bufsize; + + ptr = (char *) w_inode; + + while (length) { + clen = length; + if ((offset + length) > fs->blocksize) + clen = fs->blocksize - offset; + + if (fs->icache->buffer_blk != block_nr) { + retval = io_channel_read_blk(fs->io, block_nr, 1, + fs->icache->buffer); + if (retval) + goto errout; + fs->icache->buffer_blk = block_nr; + } + + + memcpy((char *) fs->icache->buffer + (unsigned) offset, + ptr, clen); + + retval = io_channel_write_blk(fs->io, block_nr, 1, + fs->icache->buffer); + if (retval) + goto errout; + + offset = 0; + ptr += clen; + length -= clen; + block_nr++; + } + + fs->flags |= EXT2_FLAG_CHANGED; +errout: + if (w_inode && w_inode != &temp_inode) + free(w_inode); + return retval; +} + +errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode *inode) +{ + return ext2fs_write_inode_full(fs, ino, inode, + sizeof(struct ext2_inode)); +} + +/* + * This function should be called when writing a new inode. It makes + * sure that extra part of large inodes is initialized properly. + */ +errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode *inode) +{ + struct ext2_inode *buf; + int size = EXT2_INODE_SIZE(fs->super); + struct ext2_inode_large *large_inode; + + if (size == sizeof(struct ext2_inode)) + return ext2fs_write_inode_full(fs, ino, inode, + sizeof(struct ext2_inode)); + + buf = xmalloc(size); + + memset(buf, 0, size); + *buf = *inode; + + large_inode = (struct ext2_inode_large *) buf; + large_inode->i_extra_isize = sizeof(struct ext2_inode_large) - + EXT2_GOOD_OLD_INODE_SIZE; + + return ext2fs_write_inode_full(fs, ino, buf, size); +} + + +errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks) +{ + struct ext2_inode inode; + int i; + errcode_t retval; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + if (ino > fs->super->s_inodes_count) + return EXT2_ET_BAD_INODE_NUM; + + if (fs->get_blocks) { + if (!(*fs->get_blocks)(fs, ino, blocks)) + return 0; + } + retval = ext2fs_read_inode(fs, ino, &inode); + if (retval) + return retval; + for (i=0; i < EXT2_N_BLOCKS; i++) + blocks[i] = inode.i_block[i]; + return 0; +} + +errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino) +{ + struct ext2_inode inode; + errcode_t retval; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + if (ino > fs->super->s_inodes_count) + return EXT2_ET_BAD_INODE_NUM; + + if (fs->check_directory) { + retval = (fs->check_directory)(fs, ino); + if (retval != EXT2_ET_CALLBACK_NOTHANDLED) + return retval; + } + retval = ext2fs_read_inode(fs, ino, &inode); + if (retval) + return retval; + if (!LINUX_S_ISDIR(inode.i_mode)) + return EXT2_ET_NO_DIRECTORY; + return 0; +} + |