/* Find the record in bnode that best matches key (not greater than...)*/
void hfsplus_find_rec(hfsplus_bnode *bnode, struct hfsplus_find_data *fd)
{
int cmpval;
u16 off, len, keylen;
int rec;
int b, e;
b = 0;
e = bnode->num_recs - 1;
do {
rec = (e + b) / 2;
len = hfsplus_brec_lenoff(bnode, rec, &off);
keylen = hfsplus_brec_keylen(bnode, rec);
hfsplus_bnode_readbytes(bnode, fd->key, off, keylen);
cmpval = bnode->tree->keycmp(fd->key, fd->search_key);
if (!cmpval) {
fd->exact = 1;
e = rec;
break;
}
if (cmpval < 0)
b = rec + 1;
else
e = rec - 1;
} while (b <= e);
//printk("%d: %d,%d,%d\n", bnode->this, b, e, rec);
if (rec != e && e >= 0) {
len = hfsplus_brec_lenoff(bnode, e, &off);
keylen = hfsplus_brec_keylen(bnode, e);
hfsplus_bnode_readbytes(bnode, fd->key, off, keylen);
}
fd->record = e;
fd->keyoffset = off;
fd->keylength = keylen;
fd->entryoffset = off + keylen;
fd->entrylength = len - keylen;
}
int hfsplus_btiter_move(struct hfsplus_find_data *fd, int cnt)
{
struct hfsplus_btree *tree;
hfsplus_bnode *bnode;
int idx, res = 0;
u16 off, len, keylen;
bnode = fd->bnode;
tree = bnode->tree;
if (cnt < -0xFFFF || cnt > 0xFFFF)
return -EINVAL;
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;
}
hfsplus_put_bnode(bnode);
bnode = hfsplus_find_bnode(tree, idx);
if (!bnode) {
res = -EIO;
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;
}
hfsplus_put_bnode(bnode);
bnode = hfsplus_find_bnode(tree, idx);
if (!bnode) {
res = -EIO;
goto out;
}
}
fd->record += cnt;
}
len = hfsplus_brec_lenoff(bnode, fd->record, &off);
keylen = hfsplus_brec_keylen(bnode, fd->record);
fd->keyoffset = off;
fd->keylength = keylen;
fd->entryoffset = off + keylen;
fd->entrylength = len - keylen;
hfsplus_bnode_readbytes(bnode, fd->key, off, keylen);
out:
fd->bnode = bnode;
return res;
}