Method recursivelyCheckPageKeyOrderInternal

tx_check.go:190–226

recursivelyCheckPageKeyOrderInternal verifies that all keys in the subtree rooted at `pgid` are: - >=`minKeyClosed` (can be nil) - <`maxKeyOpen` (can be nil) - Are in right ordering relationship to their parents. `pagesStack` is expected to contain IDs of pages from the tree root to `pgid` for the c

(
	pgId common.Pgid, minKeyClosed, maxKeyOpen []byte, pagesStack []common.Pgid,
	keyToString func([]byte) string, ch chan error)

//   - Are in right ordering relationship to their parents.
//     `pagesStack` is expected to contain IDs of pages from the tree root to `pgid` for the clean debugging message.
func (tx *Tx) recursivelyCheckPageKeyOrderInternal(
	pgId common.Pgid, minKeyClosed, maxKeyOpen []byte, pagesStack []common.Pgid,
	keyToString func([]byte) string, ch chan error) (maxKeyInSubtree []byte) {

	p := tx.page(pgId)
	pagesStack = append(pagesStack, pgId)
	switch {
	case p.IsBranchPage():
		// For branch page we navigate ranges of all subpages.
		runningMin := minKeyClosed
		for i := range p.BranchPageElements() {
			elem := p.BranchPageElement(uint16(i))
			verifyKeyOrder(elem.Pgid(), "branch", i, elem.Key(), runningMin, maxKeyOpen, ch, keyToString, pagesStack)

			maxKey := maxKeyOpen
			if i < len(p.BranchPageElements())-1 {
				maxKey = p.BranchPageElement(uint16(i + 1)).Key()
			}
			maxKeyInSubtree = tx.recursivelyCheckPageKeyOrderInternal(elem.Pgid(), elem.Key(), maxKey, pagesStack, keyToString, ch)
			runningMin = maxKeyInSubtree
		}
		return maxKeyInSubtree
	case p.IsLeafPage():
		runningMin := minKeyClosed
		for i := range p.LeafPageElements() {
			elem := p.LeafPageElement(uint16(i))
			verifyKeyOrder(pgId, "leaf", i, elem.Key(), runningMin, maxKeyOpen, ch, keyToString, pagesStack)
			runningMin = elem.Key()
		}
		if p.Count() > 0 {
			return p.LeafPageElement(p.Count() - 1).Key()
		}
	default:
		ch <- fmt.Errorf("unexpected page type (flags: %x) for pgId:%d", p.Flags(), pgId)
	}
	return maxKeyInSubtree
}

/***
 * verifyKeyOrder checks whether an entry with given #index on pgId (pageType: "branch|leaf") that has given "key",