Small fixes in traversal algorithm

This commit is contained in:
Sebastian Messmer 2016-07-14 12:38:25 +02:00
parent fce81f47ff
commit 35a4e42ba5

View File

@ -62,10 +62,10 @@ namespace blobstore {
DataLeafNode *leaf = dynamic_cast<DataLeafNode*>(root);
if (leaf != nullptr) {
ASSERT(beginIndex <= 1 && endIndex <= 1, "If root node is a leaf, the (sub)tree has only one leaf - access indices must be 0 or 1.");
if (beginIndex == 0 && endIndex == 1) {
if (growLastLeaf) {
leaf->resize(_nodeStore->layout().maxBytesPerLeaf());
}
if (beginIndex == 0 && endIndex == 1) {
onExistingLeaf(leafOffset, leaf);
}
return;
@ -78,6 +78,7 @@ namespace blobstore {
uint32_t endChild = utils::ceilDivision(endIndex, leavesPerChild);
ASSERT(endChild <= _nodeStore->layout().maxChildrenPerInnerNode(), "Traversal region would need increasing the tree depth. This should have happened before calling this function.");
uint32_t numChildren = inner->numChildren();
ASSERT(!growLastLeaf || endChild >= numChildren, "Can only grow last leaf if it exists");
bool shouldGrowLastExistingLeaf = growLastLeaf || endChild > numChildren;
// If we traverse outside of the valid region (i.e. usually would only traverse to new leaves and not to the last leaf),
@ -89,11 +90,10 @@ namespace blobstore {
if (childNode == none) {
throw std::runtime_error("Couldn't find child node "+childKey.ToString());
}
//TODO this causes a negative leafOffset. Better: Make leafOffset generally absolute, i.e. += beginIndex?
uint32_t negativeChildOffset = (numChildren-1) * leavesPerChild;
_traverseExistingSubtree(childNode->get(), leavesPerChild-1, leavesPerChild, leafOffset - negativeChildOffset, true,
[] (uint32_t /*index*/, DataLeafNode* /*leaf*/) {},
_createMaxSizeLeaf(),
uint32_t childOffset = (numChildren-1) * leavesPerChild;
_traverseExistingSubtree(childNode->get(), leavesPerChild, leavesPerChild, childOffset, true,
[] (uint32_t /*index*/, DataLeafNode* /*leaf*/) {ASSERT(false, "We don't actually traverse any leaves.");},
[] (uint32_t /*index*/) -> Data {ASSERT(false, "We don't actually traverse any leaves.");},
[] (DataInnerNode* /*node*/) {});
}