int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
{
int cmpval;
u16 off, len, keylen;
int rec;
int b, e;
int res;
b = 0;
e = bnode->num_recs - 1;
res = -ENOENT;
do {
rec = (e + b) / 2;
len = hfs_brec_lenoff(bnode, rec, &off);
keylen = hfs_brec_keylen(bnode, rec);
if (keylen == 0) {
res = -EINVAL;
goto fail;
}
hfs_bnode_read(bnode, fd->key, off, keylen);
cmpval = bnode->tree->keycmp(fd->key, fd->search_key);
if (!cmpval) {
e = rec;
res = 0;
goto done;
}
if (cmpval < 0)
b = rec + 1;
else
e = rec - 1;
} while (b <= e);
if (rec != e && e >= 0) {
len = hfs_brec_lenoff(bnode, e, &off);
keylen = hfs_brec_keylen(bnode, e);
if (keylen == 0) {
res = -EINVAL;
goto fail;
}
hfs_bnode_read(bnode, fd->key, off, keylen);
}
done:
fd->record = e;
fd->keyoffset = off;
fd->keylength = keylen;
fd->entryoffset = off + keylen;
fd->entrylength = len - keylen;
fail:
return res;
}
/* Find the record in bnode that best matches key (not greater than...)*/
int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd,
search_strategy_t rec_found)
{
u16 off, len, keylen;
int rec;
int b, e;
int res;
if (!rec_found)
BUG();
b = 0;
e = bnode->num_recs - 1;
res = -ENOENT;
do {
rec = (e + b) / 2;
len = hfs_brec_lenoff(bnode, rec, &off);
keylen = hfs_brec_keylen(bnode, rec);
if (keylen == 0) {
res = -EINVAL;
goto fail;
}
hfs_bnode_read(bnode, fd->key, off, keylen);
if (rec_found(bnode, fd, &b, &e, &rec)) {
res = 0;
goto done;
}
} while (b <= e);
if (rec != e && e >= 0) {
len = hfs_brec_lenoff(bnode, e, &off);
keylen = hfs_brec_keylen(bnode, e);
if (keylen == 0) {
res = -EINVAL;
goto fail;
}
hfs_bnode_read(bnode, fd->key, off, keylen);
}
done:
fd->record = e;
fd->keyoffset = off;
fd->keylength = keylen;
fd->entryoffset = off + keylen;
fd->entrylength = len - keylen;
fail:
return res;
}
int hfs_brec_goto(struct hfs_find_data *fd, int cnt)
{
struct hfs_btree *tree;
struct hfs_bnode *bnode;
int idx, res = 0;
u16 off, len, keylen;
bnode = fd->bnode;
tree = bnode->tree;
if (cnt < 0) {
cnt = -cnt;
while (cnt > fd->record) {
cnt -= fd->record + 1;
fd->record = bnode->num_recs - 1;
idx = bnode->prev;
if (!idx) {
res = -ENOENT;
goto out;
}
hfs_bnode_put(bnode);
bnode = hfs_bnode_find(tree, idx);
if (IS_ERR(bnode)) {
res = PTR_ERR(bnode);
bnode = NULL;
goto out;
}
}
fd->record -= cnt;
} else {
while (cnt >= bnode->num_recs - fd->record) {
cnt -= bnode->num_recs - fd->record;
fd->record = 0;
idx = bnode->next;
if (!idx) {
res = -ENOENT;
goto out;
}
hfs_bnode_put(bnode);
bnode = hfs_bnode_find(tree, idx);
if (IS_ERR(bnode)) {
res = PTR_ERR(bnode);
bnode = NULL;
goto out;
}
}
fd->record += cnt;
}
len = hfs_brec_lenoff(bnode, fd->record, &off);
keylen = hfs_brec_keylen(bnode, fd->record);
fd->keyoffset = off;
fd->keylength = keylen;
fd->entryoffset = off + keylen;
fd->entrylength = len - keylen;
hfs_bnode_read(bnode, fd->key, off, keylen);
out:
fd->bnode = bnode;
return res;
}