HFS+: add custom dentry hash and comparison operations

Add custom dentry hash and comparison operations for HFS+ filesystems that are
case-insensitive and/or do automatic unicode decomposition.  The new
operations reuse the existing HFS+ ASCII to unicode conversion, unicode
decomposition and case folding functionality.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Duane Griffin 2007-07-15 23:41:23 -07:00 committed by Linus Torvalds
parent 1e96b7ca1e
commit d45bce8faf
6 changed files with 138 additions and 1 deletions

View File

@ -62,8 +62,10 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id)
if ((HFSPLUS_SB(sb).flags & HFSPLUS_SB_HFSX) &&
(head->key_type == HFSPLUS_KEY_BINARY))
tree->keycmp = hfsplus_cat_bin_cmp_key;
else
else {
tree->keycmp = hfsplus_cat_case_cmp_key;
HFSPLUS_SB(sb).flags |= HFSPLUS_SB_CASEFOLD;
}
} else {
printk(KERN_ERR "hfs: unknown B*Tree requested\n");
goto fail_page;

View File

@ -36,6 +36,8 @@ static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
u16 type;
sb = dir->i_sb;
dentry->d_op = &hfsplus_dentry_operations;
dentry->d_fsdata = NULL;
hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);

View File

@ -150,6 +150,7 @@ struct hfsplus_sb_info {
#define HFSPLUS_SB_NODECOMPOSE 0x0002
#define HFSPLUS_SB_FORCE 0x0004
#define HFSPLUS_SB_HFSX 0x0008
#define HFSPLUS_SB_CASEFOLD 0x0010
struct hfsplus_inode_info {
@ -321,6 +322,7 @@ void hfsplus_file_truncate(struct inode *);
/* inode.c */
extern const struct address_space_operations hfsplus_aops;
extern const struct address_space_operations hfsplus_btree_aops;
extern struct dentry_operations hfsplus_dentry_operations;
void hfsplus_inode_read_fork(struct inode *, struct hfsplus_fork_raw *);
void hfsplus_inode_write_fork(struct inode *, struct hfsplus_fork_raw *);
@ -353,6 +355,8 @@ int hfsplus_strcasecmp(const struct hfsplus_unistr *, const struct hfsplus_unist
int hfsplus_strcmp(const struct hfsplus_unistr *, const struct hfsplus_unistr *);
int hfsplus_uni2asc(struct super_block *, const struct hfsplus_unistr *, char *, int *);
int hfsplus_asc2uni(struct super_block *, struct hfsplus_unistr *, const char *, int);
int hfsplus_hash_dentry(struct dentry *dentry, struct qstr *str);
int hfsplus_compare_dentry(struct dentry *dentry, struct qstr *s1, struct qstr *s2);
/* wrapper.c */
int hfsplus_read_wrapper(struct super_block *);

View File

@ -131,6 +131,11 @@ const struct address_space_operations hfsplus_aops = {
.writepages = hfsplus_writepages,
};
struct dentry_operations hfsplus_dentry_operations = {
.d_hash = hfsplus_hash_dentry,
.d_compare = hfsplus_compare_dentry,
};
static struct dentry *hfsplus_file_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{

View File

@ -380,6 +380,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
iput(root);
goto cleanup;
}
sb->s_root->d_op = &hfsplus_dentry_operations;
str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
str.name = HFSP_HIDDENDIR_NAME;

View File

@ -314,3 +314,126 @@ int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
return -ENAMETOOLONG;
return 0;
}
/*
* Hash a string to an integer as appropriate for the HFS+ filesystem.
* Composed unicode characters are decomposed and case-folding is performed
* if the appropriate bits are (un)set on the superblock.
*/
int hfsplus_hash_dentry(struct dentry *dentry, struct qstr *str)
{
struct super_block *sb = dentry->d_sb;
const char *astr;
const u16 *dstr;
int casefold, decompose, size, dsize, len;
unsigned long hash;
wchar_t c;
u16 c2;
casefold = (HFSPLUS_SB(sb).flags & HFSPLUS_SB_CASEFOLD);
decompose = !(HFSPLUS_SB(sb).flags & HFSPLUS_SB_NODECOMPOSE);
hash = init_name_hash();
astr = str->name;
len = str->len;
while (len > 0) {
size = asc2unichar(sb, astr, len, &c);
astr += size;
len -= size;
if (decompose && (dstr = decompose_unichar(c, &dsize))) {
do {
c2 = *dstr++;
if (!casefold || (c2 = case_fold(c2)))
hash = partial_name_hash(c2, hash);
} while (--dsize > 0);
} else {
c2 = c;
if (!casefold || (c2 = case_fold(c2)))
hash = partial_name_hash(c2, hash);
}
}
str->hash = end_name_hash(hash);
return 0;
}
/*
* Compare strings with HFS+ filename ordering.
* Composed unicode characters are decomposed and case-folding is performed
* if the appropriate bits are (un)set on the superblock.
*/
int hfsplus_compare_dentry(struct dentry *dentry, struct qstr *s1, struct qstr *s2)
{
struct super_block *sb = dentry->d_sb;
int casefold, decompose, size;
int dsize1, dsize2, len1, len2;
const u16 *dstr1, *dstr2;
const char *astr1, *astr2;
u16 c1, c2;
wchar_t c;
casefold = (HFSPLUS_SB(sb).flags & HFSPLUS_SB_CASEFOLD);
decompose = !(HFSPLUS_SB(sb).flags & HFSPLUS_SB_NODECOMPOSE);
astr1 = s1->name;
len1 = s1->len;
astr2 = s2->name;
len2 = s2->len;
dsize1 = dsize2 = 0;
dstr1 = dstr2 = NULL;
while (len1 > 0 && len2 > 0) {
if (!dsize1) {
size = asc2unichar(sb, astr1, len1, &c);
astr1 += size;
len1 -= size;
if (!decompose || !(dstr1 = decompose_unichar(c, &dsize1))) {
c1 = c;
dstr1 = &c1;
dsize1 = 1;
}
}
if (!dsize2) {
size = asc2unichar(sb, astr2, len2, &c);
astr2 += size;
len2 -= size;
if (!decompose || !(dstr2 = decompose_unichar(c, &dsize2))) {
c2 = c;
dstr2 = &c2;
dsize2 = 1;
}
}
c1 = *dstr1;
c2 = *dstr2;
if (casefold) {
if (!(c1 = case_fold(c1))) {
dstr1++;
dsize1--;
continue;
}
if (!(c2 = case_fold(c2))) {
dstr2++;
dsize2--;
continue;
}
}
if (c1 < c2)
return -1;
else if (c1 > c2)
return 1;
dstr1++;
dsize1--;
dstr2++;
dsize2--;
}
if (len1 < len2)
return -1;
if (len1 > len2)
return 1;
return 0;
}