func (btree *Btree) Print() {
if btree.rootblock == 0 {
return
}
b := btree.Cache.GetBuf(btree.rootblock)
if b == nil {
fmt.Println("btree didn't find root")
return
}
head := (*Head)(unsafe.Pointer(&b.Data[0]))
switch head.kind {
case LEAF:
var leaf Leaf
leaf.b = b
leaf.head = head
leaf.rec = leaf.recSlice()
leaf.Print()
case BRANCH:
var branch Branch
branch.b = b
branch.head = head
branch.twig = *(*[]Twig)(unsafe.Pointer(&b.Data[sizeHead]))
branch.Print()
default:
bug.Pr("Not a leaf or branch", head.kind)
}
}
func (branch *Branch) store(i Len, key []byte, block int64) {
bug.Pr("key", string(key), "block", block)
for j := Len(0); j < LenBlockNum; j++ {
branch.head.end--
branch.b.Data[branch.head.end] = byte(block)
block >>= 8
}
branch.storeSlice(key)
branch.storeIndex(i, branch.head.end)
}
func (btree *Btree) Insert(key, value []byte) {
if len(key)+len(value) > MAX_KEY_VAL {
bug.Pr("kay/value too big %d", len(key)+len(value))
return
}
if btree.rootblock == 0 {
leaf := btree.newLeaf()
btree.rootblock = leaf.head.block
leaf.b.Put()
}
b := btree.Cache.GetBuf(btree.rootblock)
if b == nil {
fmt.Println("btree didn't find root")
return
}
head := (*Head)(unsafe.Pointer(&b.Data[0]))
if head.overflow != 0 {
bug.Pr("Need to grow tree")
return
}
switch head.kind {
case LEAF:
var leaf Leaf
leaf.b = b
leaf.head = head
leaf.rec = leaf.recSlice()
leaf.insert(key, value)
case BRANCH:
var branch Branch
branch.b = b
branch.head = head
branch.twig = *(*[]Twig)(unsafe.Pointer(&b.Data[sizeHead]))
branch.insert(key, value)
default:
bug.Pr("Not a leaf or branch", b.Data[0])
}
}
func (leaf *Leaf) grow() *Branch {
if !leaf.isSplit() {
panic("trying to grow an unsplit leaf")
}
if leaf.head.block != leaf.btree.root {
panic("leaf block not root")
}
branch := leaf.btree.newBranch()
key := leaf.getKey(leaf.head.numrecs - 1)
branch.store(0, key, leaf.head.block)
branch.head.last = leaf.head.overflow
leaf.head.overflow = 0
leaf.btree.root = branch.head.block
branch.print(3)
bug.Pr(branch.b.Data)
return branch
}