/*
* parse_new_part_table()
*
* Parse a new style partition map looking for the
* start and length of the 'part'th HFS partition.
*/
static int parse_new_part_table(hfs_sysmdb sys_mdb, hfs_buffer buf,
int part, hfs_s32 *size, hfs_s32 *start)
{
struct new_pmap *pm = (struct new_pmap *)hfs_buffer_data(buf);
hfs_u32 pmap_entries = hfs_get_hl(pm->pmMapBlkCnt);
int hfs_part = 0;
int entry;
for (entry = 0; (entry < pmap_entries) && !(*start); ++entry) {
if (entry) {
/* read the next partition map entry */
buf = hfs_buffer_get(sys_mdb, HFS_PMAP_BLK + entry, 1);
if (!hfs_buffer_ok(buf)) {
hfs_warn("hfs_fs: unable to "
"read partition map.\n");
goto bail;
}
pm = (struct new_pmap *)hfs_buffer_data(buf);
if (hfs_get_ns(pm->pmSig) !=
htons(HFS_NEW_PMAP_MAGIC)) {
hfs_warn("hfs_fs: invalid "
"entry in partition map\n");
hfs_buffer_put(buf);
goto bail;
}
}
/* look for an HFS partition */
if (!memcmp(pm->pmPartType,"Apple_HFS",9) &&
((hfs_part++) == part)) {
/* Found it! */
*start = hfs_get_hl(pm->pmPyPartStart);
*size = hfs_get_hl(pm->pmPartBlkCnt);
}
hfs_buffer_put(buf);
}
return 0;
bail:
return 1;
}
/*
* hfs_ext_compare()
*
* Description:
* This is the comparison function used for the extents B-tree. In
* comparing extent B-tree entries, the file id is the most
* significant field (compared as unsigned ints); the fork type is
* the second most significant field (compared as unsigned chars);
* and the allocation block number field is the least significant
* (compared as unsigned ints).
* Input Variable(s):
* struct hfs_ext_key *key1: pointer to the first key to compare
* struct hfs_ext_key *key2: pointer to the second key to compare
* Output Variable(s):
* NONE
* Returns:
* int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
* Preconditions:
* key1 and key2 point to "valid" (struct hfs_ext_key)s.
* Postconditions:
* This function has no side-effects */
int hfs_ext_compare(const struct hfs_ext_key *key1,
const struct hfs_ext_key *key2)
{
unsigned int tmp;
int retval;
tmp = hfs_get_hl(key1->FNum) - hfs_get_hl(key2->FNum);
if (tmp != 0) {
retval = (int)tmp;
} else {
tmp = (unsigned char)key1->FkType - (unsigned char)key2->FkType;
if (tmp != 0) {
retval = (int)tmp;
} else {
retval = (int)(hfs_get_hs(key1->FABN)
- hfs_get_hs(key2->FABN));
}
}
return retval;
}
/*
* parse_old_part_table()
*
* Parse a old style partition map looking for the
* start and length of the 'part'th HFS partition.
*/
static int parse_old_part_table(hfs_sysmdb sys_mdb, hfs_buffer buf,
int part, hfs_s32 *size, hfs_s32 *start)
{
struct old_pmap *pm = (struct old_pmap *)hfs_buffer_data(buf);
struct old_pmap_entry *p = &pm->pdEntry[0];
int hfs_part = 0;
while ((p->pdStart || p->pdSize || p->pdFSID) && !(*start)) {
/* look for an HFS partition */
if ((hfs_get_nl(p->pdFSID) == htonl(0x54465331)/*"TFS1"*/) &&
((hfs_part++) == part)) {
/* Found it! */
*start = hfs_get_hl(p->pdStart);
*size = hfs_get_hl(p->pdSize);
}
++p;
}
hfs_buffer_put(buf);
return 0;
}
/*
* hfs_btree_init()
*
* Description:
* Given some vital information from the MDB (HFS superblock),
* initializes the fields of a (struct hfs_btree).
* Input Variable(s):
* struct hfs_mdb *mdb: pointer to the MDB
* ino_t cnid: the CNID (HFS_CAT_CNID or HFS_EXT_CNID) of the B-tree
* hfs_u32 tsize: the size, in bytes, of the B-tree
* hfs_u32 csize: the size, in bytes, of the clump size for the B-tree
* Output Variable(s):
* NONE
* Returns:
* (struct hfs_btree *): pointer to the initialized hfs_btree on success,
* or NULL on failure
* Preconditions:
* 'mdb' points to a "valid" (struct hfs_mdb)
* Postconditions:
* Assuming the inputs are what they claim to be, no errors occur
* reading from disk, and no inconsistencies are noticed in the data
* read from disk, the return value is a pointer to a "valid"
* (struct hfs_btree). If there are errors reading from disk or
* inconsistencies are noticed in the data read from disk, then and
* all resources that were allocated are released and NULL is
* returned. If the inputs are not what they claim to be or if they
* are unnoticed inconsistencies in the data read from disk then the
* returned hfs_btree is probably going to lead to errors when it is
* used in a non-trivial way.
*/
struct hfs_btree * hfs_btree_init(struct hfs_mdb *mdb, ino_t cnid,
hfs_byte_t ext[12],
hfs_u32 tsize, hfs_u32 csize)
{
struct hfs_btree * bt;
struct BTHdrRec * th;
struct hfs_bnode * tmp;
unsigned int next;
#if defined(DEBUG_HEADER) || defined(DEBUG_ALL)
unsigned char *p, *q;
#endif
if (!mdb || !ext || !HFS_NEW(bt)) {
goto bail3;
}
bt->magic = HFS_BTREE_MAGIC;
bt->sys_mdb = mdb->sys_mdb;
bt->reserved = 0;
bt->lock = 0;
hfs_init_waitqueue(&bt->wait);
bt->dirt = 0;
memset(bt->cache, 0, sizeof(bt->cache));
#if 0 /* this is a fake entry. so we don't need to initialize it. */
memset(&bt->entry, 0, sizeof(bt->entry));
hfs_init_waitqueue(&bt->entry.wait);
INIT_LIST_HEAD(&bt->entry.hash);
INIT_LIST_HEAD(&bt->entry.list);
#endif
bt->entry.mdb = mdb;
bt->entry.cnid = cnid;
bt->entry.type = HFS_CDR_FIL;
bt->entry.u.file.magic = HFS_FILE_MAGIC;
bt->entry.u.file.clumpablks = (csize / mdb->alloc_blksz)
>> HFS_SECTOR_SIZE_BITS;
bt->entry.u.file.data_fork.entry = &bt->entry;
bt->entry.u.file.data_fork.lsize = tsize;
bt->entry.u.file.data_fork.psize = tsize >> HFS_SECTOR_SIZE_BITS;
bt->entry.u.file.data_fork.fork = HFS_FK_DATA;
hfs_extent_in(&bt->entry.u.file.data_fork, ext);
hfs_bnode_read(&bt->head, bt, 0, HFS_STICKY);
if (!hfs_buffer_ok(bt->head.buf)) {
goto bail2;
}
th = (struct BTHdrRec *)((char *)hfs_buffer_data(bt->head.buf) +
sizeof(struct NodeDescriptor));
/* read in the bitmap nodes (if any) */
tmp = &bt->head;
while ((next = tmp->ndFLink)) {
if (!HFS_NEW(tmp->next)) {
goto bail2;
}
hfs_bnode_read(tmp->next, bt, next, HFS_STICKY);
if (!hfs_buffer_ok(tmp->next->buf)) {
goto bail2;
}
tmp->next->prev = tmp;
tmp = tmp->next;
}
if (hfs_get_ns(th->bthNodeSize) != htons(HFS_SECTOR_SIZE)) {
hfs_warn("hfs_btree_init: bthNodeSize!=512 not supported\n");
goto bail2;
}
if (cnid == htonl(HFS_CAT_CNID)) {
bt->compare = (hfs_cmpfn)hfs_cat_compare;
} else if (cnid == htonl(HFS_EXT_CNID)) {
bt->compare = (hfs_cmpfn)hfs_ext_compare;
} else {
goto bail2;
}
bt->bthDepth = hfs_get_hs(th->bthDepth);
bt->bthRoot = hfs_get_hl(th->bthRoot);
bt->bthNRecs = hfs_get_hl(th->bthNRecs);
bt->bthFNode = hfs_get_hl(th->bthFNode);
bt->bthLNode = hfs_get_hl(th->bthLNode);
bt->bthNNodes = hfs_get_hl(th->bthNNodes);
bt->bthFree = hfs_get_hl(th->bthFree);
bt->bthKeyLen = hfs_get_hs(th->bthKeyLen);
#if defined(DEBUG_HEADER) || defined(DEBUG_ALL)
hfs_warn("bthDepth %d\n", bt->bthDepth);
hfs_warn("bthRoot %d\n", bt->bthRoot);
hfs_warn("bthNRecs %d\n", bt->bthNRecs);
hfs_warn("bthFNode %d\n", bt->bthFNode);
hfs_warn("bthLNode %d\n", bt->bthLNode);
hfs_warn("bthKeyLen %d\n", bt->bthKeyLen);
hfs_warn("bthNNodes %d\n", bt->bthNNodes);
hfs_warn("bthFree %d\n", bt->bthFree);
p = (unsigned char *)hfs_buffer_data(bt->head.buf);
q = p + HFS_SECTOR_SIZE;
while (p < q) {
hfs_warn("%02x %02x %02x %02x %02x %02x %02x %02x "
"%02x %02x %02x %02x %02x %02x %02x %02x\n",
*p++, *p++, *p++, *p++, *p++, *p++, *p++, *p++,
*p++, *p++, *p++, *p++, *p++, *p++, *p++, *p++);
}
#endif
/* Read in the root if it exists.
The header always exists, but the root exists only if the
tree is non-empty */
if (bt->bthDepth && bt->bthRoot) {
if (!HFS_NEW(bt->root)) {
goto bail2;
}
hfs_bnode_read(bt->root, bt, bt->bthRoot, HFS_STICKY);
if (!hfs_buffer_ok(bt->root->buf)) {
goto bail1;
}
} else {
bt->root = NULL;
}
return bt;
bail1:
hfs_bnode_ditch(bt->root);
bail2:
hfs_bnode_ditch(&bt->head);
HFS_DELETE(bt);
bail3:
return NULL;
}
/*
* del_root()
*
* Description:
* Delete the current root bnode.
* Input Variable(s):
* struct hfs_bnode_ref *root: reference to the root bnode
* Output Variable(s):
* NONE
* Returns:
* int: 0 on success, error code on failure
* Preconditions:
* 'root' refers to the root bnode with HFS_LOCK_WRITE access.
* None of 'root's children are held with HFS_LOCK_WRITE access.
* Postconditions:
* The current 'root' node is removed from the tree and the depth
* of the tree is reduced by one.
* If 'root' is an index node with exactly one child, then that
* child becomes the new root of the tree.
* If 'root' is an empty leaf node the tree becomes empty.
* Upon return access to 'root' is relinquished.
*/
static int del_root(struct hfs_bnode_ref *root)
{
struct hfs_btree *tree = root->bn->tree;
struct hfs_bnode_ref child;
hfs_u32 node;
if (root->bn->ndNRecs > 1) {
return 0;
} else if (root->bn->ndNRecs == 0) {
/* tree is empty */
tree->bthRoot = 0;
tree->root = NULL;
tree->bthRoot = 0;
tree->bthFNode = 0;
tree->bthLNode = 0;
--tree->bthDepth;
tree->dirt = 1;
if (tree->bthDepth) {
hfs_warn("hfs_bdelete: empty tree with bthDepth=%d\n",
tree->bthDepth);
goto bail;
}
return hfs_bnode_free(root);
} else if (root->bn->ndType == ndIndxNode) {
/* tree is non-empty */
node = hfs_get_hl(bkey_record(bnode_datastart(root->bn)));
child = hfs_bnode_find(tree, node, HFS_LOCK_READ);
if (!child.bn) {
hfs_warn("hfs_bdelete: can't read child node.\n");
goto bail;
}
child.bn->sticky = HFS_STICKY;
if (child.bn->next) {
child.bn->next->prev = child.bn->prev;
}
if (child.bn->prev) {
child.bn->prev->next = child.bn->next;
}
if (bhash(tree, child.bn->node) == child.bn) {
bhash(tree, child.bn->node) = child.bn->next;
}
child.bn->next = NULL;
child.bn->prev = NULL;
tree->bthRoot = child.bn->node;
tree->root = child.bn;
/* re-assign bthFNode and bthLNode if the new root is
a leaf node. */
if (child.bn->ndType == ndLeafNode) {
tree->bthFNode = node;
tree->bthLNode = node;
}
hfs_bnode_relse(&child);
tree->bthRoot = node;
--tree->bthDepth;
tree->dirt = 1;
if (!tree->bthDepth) {
hfs_warn("hfs_bdelete: non-empty tree with "
"bthDepth == 0\n");
goto bail;
}
return hfs_bnode_free(root); /* marks tree dirty */
}
hfs_bnode_relse(root);
return 0;
bail:
hfs_bnode_relse(root);
return -EIO;
}
