libcryfs/implementations/onblocks/datanodestore/DataLeafNode.cpp

68 lines
2.2 KiB
C++

#include "DataLeafNode.h"
#include "DataInnerNode.h"
#include <messmer/cpp-utils/assert/assert.h>
using blockstore::Block;
using cpputils::Data;
using blockstore::Key;
using cpputils::unique_ref;
using cpputils::make_unique_ref;
namespace blobstore {
namespace onblocks {
namespace datanodestore {
DataLeafNode::DataLeafNode(DataNodeView view)
: DataNode(std::move(view)) {
ASSERT(node().Depth() == 0, "Leaf node must have depth 0. Is it an inner node instead?");
ASSERT(numBytes() <= maxStoreableBytes(), "Leaf says it stores more bytes than it has space for");
}
DataLeafNode::~DataLeafNode() {
}
unique_ref<DataLeafNode> DataLeafNode::InitializeNewNode(unique_ref<Block> block) {
DataNodeView node(std::move(block));
node.setDepth(0);
node.setSize(0);
//fillDataWithZeroes(); not needed, because a newly created block will be zeroed out. DataLeafNodeTest.SpaceIsZeroFilledWhenGrowing ensures this.
return make_unique_ref<DataLeafNode>(std::move(node));
}
void DataLeafNode::read(void *target, uint64_t offset, uint64_t size) const {
ASSERT(offset <= node().Size() && offset + size <= node().Size(), "Read out of valid area"); // Also check offset, because the addition could lead to overflows
std::memcpy(target, (uint8_t*)node().data() + offset, size);
}
void DataLeafNode::write(const void *source, uint64_t offset, uint64_t size) {
ASSERT(offset <= node().Size() && offset + size <= node().Size(), "Write out of valid area"); // Also check offset, because the addition could lead to overflows
node().write(source, offset, size);
}
uint32_t DataLeafNode::numBytes() const {
return node().Size();
}
void DataLeafNode::resize(uint32_t new_size) {
ASSERT(new_size <= maxStoreableBytes(), "Trying to resize to a size larger than the maximal size");
uint32_t old_size = node().Size();
if (new_size < old_size) {
fillDataWithZeroesFromTo(new_size, old_size);
}
node().setSize(new_size);
}
void DataLeafNode::fillDataWithZeroesFromTo(off_t begin, off_t end) {
Data ZEROES(end-begin);
ZEROES.FillWithZeroes();
node().write(ZEROES.data(), begin, end-begin);
}
uint32_t DataLeafNode::maxStoreableBytes() const {
return node().layout().maxBytesPerLeaf();
}
}
}
}