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Small fixes in traversal algorithm

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This commit is contained in:
Sebastian Messmer 2016-07-14 12:38:25 +02:00
parent fce81f47ff
commit 35a4e42ba5
1 changed files with 8 additions and 8 deletions
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16
src/blobstore/implementations/onblocks/datatreestore/impl/LeafTraverser.cpp
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@ -62,10 +62,10 @@ namespace blobstore {
DataLeafNode *leaf = dynamic_cast<DataLeafNode*>(root); DataLeafNode *leaf = dynamic_cast<DataLeafNode*>(root);
if (leaf != nullptr) { 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."); 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 (growLastLeaf) {
leaf->resize(_nodeStore->layout().maxBytesPerLeaf());
}
if (beginIndex == 0 && endIndex == 1) { if (beginIndex == 0 && endIndex == 1) {
if (growLastLeaf) {
leaf->resize(_nodeStore->layout().maxBytesPerLeaf());
}
onExistingLeaf(leafOffset, leaf); onExistingLeaf(leafOffset, leaf);
} }
return; return;
@ -78,6 +78,7 @@ namespace blobstore {
uint32_t endChild = utils::ceilDivision(endIndex, leavesPerChild); 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."); 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(); uint32_t numChildren = inner->numChildren();
ASSERT(!growLastLeaf || endChild >= numChildren, "Can only grow last leaf if it exists");
bool shouldGrowLastExistingLeaf = growLastLeaf || endChild > numChildren; 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), // 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) { if (childNode == none) {
throw std::runtime_error("Couldn't find child node "+childKey.ToString()); 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 childOffset = (numChildren-1) * leavesPerChild;
uint32_t negativeChildOffset = (numChildren-1) * leavesPerChild; _traverseExistingSubtree(childNode->get(), leavesPerChild, leavesPerChild, childOffset, true,
_traverseExistingSubtree(childNode->get(), leavesPerChild-1, leavesPerChild, leafOffset - negativeChildOffset, true, [] (uint32_t /*index*/, DataLeafNode* /*leaf*/) {ASSERT(false, "We don't actually traverse any leaves.");},
[] (uint32_t /*index*/, DataLeafNode* /*leaf*/) {}, [] (uint32_t /*index*/) -> Data {ASSERT(false, "We don't actually traverse any leaves.");},
_createMaxSizeLeaf(),
[] (DataInnerNode* /*node*/) {}); [] (DataInnerNode* /*node*/) {});
} }