1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2020 Bootlin
5 * Author: Joao Marcos Costa <joaomarcos.costa@bootlin.com>
9 #include <linux/types.h>
10 #include <linux/byteorder/little_endian.h>
11 #include <linux/byteorder/generic.h>
16 #include "sqfs_filesystem.h"
17 #include "sqfs_utils.h"
19 bool sqfs_is_dir(u16 type)
21 return type == SQFS_DIR_TYPE || type == SQFS_LDIR_TYPE;
25 * Receives a pointer (void *) to a position in the inode table containing the
26 * directory's inode. Returns directory inode offset into the directory table.
27 * m_list contains each metadata block's position, and m_count is the number of
28 * elements of m_list. Those metadata blocks come from the compressed directory
31 int sqfs_dir_offset(void *dir_i, u32 *m_list, int m_count)
33 struct squashfs_base_inode *base = dir_i;
34 struct squashfs_ldir_inode *ldir;
35 struct squashfs_dir_inode *dir;
40 switch (get_unaligned_le16(&base->inode_type)) {
42 dir = (struct squashfs_dir_inode *)base;
43 start_block = get_unaligned_le32(&dir->start_block);
44 offset = get_unaligned_le16(&dir->offset);
47 ldir = (struct squashfs_ldir_inode *)base;
48 start_block = get_unaligned_le32(&ldir->start_block);
49 offset = get_unaligned_le16(&ldir->offset);
52 printf("Error: this is not a directory.\n");
59 for (j = 0; j < m_count; j++) {
60 if (m_list[j] == start_block)
61 return (++j * SQFS_METADATA_BLOCK_SIZE) + offset;
67 printf("Error: invalid inode reference to directory table.\n");
72 bool sqfs_is_empty_dir(void *dir_i)
74 struct squashfs_base_inode *base = dir_i;
75 struct squashfs_ldir_inode *ldir;
76 struct squashfs_dir_inode *dir;
79 switch (get_unaligned_le16(&base->inode_type)) {
81 dir = (struct squashfs_dir_inode *)base;
82 file_size = get_unaligned_le16(&dir->file_size);
85 ldir = (struct squashfs_ldir_inode *)base;
86 file_size = get_unaligned_le16(&ldir->file_size);
89 printf("Error: this is not a directory.\n");
93 return file_size == SQFS_EMPTY_FILE_SIZE;