private Frame(int start, int end, int leftbound, int rightbound, Frame parent, int frameId)
{
this.frameId = frameId;
this.start = start;
this.end = end;
this.leftbound = leftbound;
this.rightbound = rightbound;
this.parent = parent;
}
public Frame(int start, int end)
{
this.frameId = currentFrameId++;
this.start = start;
this.end = end;
this.leftbound = start;
this.rightbound = end;
this.parent = null;
}
public HashSet<int> AddNewGroup(int origId, int currentId, int k, AnonyGroupEntry anonGroups,
Dictionary<int, SubTreeEntry> subtree, ref List<int> swapList)
{
PrivacyGlobal global = (PrivacyGlobal)Global.getInstance();
HashSet<int> newgroup = new HashSet<int>();
swapList = new List<int>();
int step;
//预处理 复制一个相同的数组
HashSet<Frame> lframes = new HashSet<Frame>();
HashSet<Frame> lallframes = new HashSet<Frame>();
List<FrameNode> lnodes = new List<FrameNode>();
//建立映射关系
Dictionary<FrameNode, int> nodeIndexMapping = new Dictionary<FrameNode, int>();
Dictionary<int, int> nodeIdIndexMapping = new Dictionary<int, int>();
Dictionary<int, Frame> frameIdIndexMapping = new Dictionary<int, Frame>();
foreach (Frame frame in allframes)
{
Frame framecopy = (Frame)frame.Clone();
if (frames.Contains(frame))
{
lframes.Add(framecopy);
frameIdIndexMapping.Add(frame.frameId, framecopy);
}
lallframes.Add(framecopy);
}
for (int i = 0; i < nodes.Count; i++)
{
lnodes.Add((FrameNode)nodes[i].Clone());
FrameNode node = lnodes[i];
nodeIndexMapping.Add(node, i);
nodeIdIndexMapping.Add(node.nodeId, i);
}
//步骤1 将框内所有已加入k-匿名组的节点置为不可用，这个对框结构没有影响
step = 1;
jointNodeIds = new HashSet<int>();
foreach (int c in subtree.Keys)
{
if (anonGroups.subUnavailAnonyNodes.ContainsKey(c + "-" + k))
{
foreach (int nodeId in anonGroups.subUnavailAnonyNodes[c + "-" + k])
jointNodeIds.Add(nodeId);
}
}
STEP2:
//步骤2 将非本节点子树的节点去掉，将原始框分割为新的框集，这个会减少框的大小
if (step < 4)
step = 2;
childNodeIds = new HashSet<int>();
foreach (FrameNode node in lnodes)
{
int nodeId = node.nodeId;
if (subtree.ContainsKey(nodeId) || currentId == nodeId)
{
childNodeIds.Add(nodeId);
continue;
}
foreach (KeyValuePair<int, SubTreeEntry> pair in subtree)
{
if (pair.Value.subnodes.Contains(nodeId))
{
childNodeIds.Add(nodeId);
break;
}
}
}
//步骤3 将原始节点放到框的可用最左侧
if(step<4)
step = 3;
int origIndex = nodeIdIndexMapping[origId];
FrameNode origNode = lnodes[origIndex];
Frame origFrame = frameIdIndexMapping[origNode.belongedFrameId];
for (int i = origFrame.start; i <= origFrame.end; i++)
{
//如果框内有节点不是自己的子节点，则将请求转发到父节点，否则可能会分裂该框，造成不一致性
if (!IsChild(lnodes[i].nodeId))
return null;
}
int leftIndex = origFrame.start;
do
{
if ((lnodes[leftIndex].anchor == false || origId == lnodes[leftIndex].nodeId) && IsNodeAvailable(lnodes[leftIndex].nodeId))
break;
leftIndex++;
} while (leftIndex < origIndex);
if (leftIndex < origIndex && IsNodeAvailable(lnodes[leftIndex].nodeId))
{
//swap
SwapNodes(origIndex, leftIndex, lnodes, nodeIndexMapping, nodeIdIndexMapping);
origIndex = nodeIdIndexMapping[origId];
origNode = lnodes[origIndex];
origFrame = frameIdIndexMapping[origNode.belongedFrameId];
Console.WriteLine("swap nodes");
}
lnodes[leftIndex].anchor = true;
DumpFrames(lframes, lnodes, frameIdIndexMapping, currentId);
//如果本节点已在匿名组内，则直接返回。这里不在开始就处理是因为要将其置于框最左侧
foreach (int c in subtree.Keys)
{
if (anonGroups.subUnavailAnonyNodes.ContainsKey(c + "-" + k)
&& anonGroups.subUnavailAnonyNodes[c + "-" + k].Contains(origId))
{
Console.WriteLine("READER{0} is already in {1}-group", origId, k);
Utility.CopyHashSet(newgroup, anonGroups.groups[k]);
goto DONE;
}
}
//之前没有判断子树节点，是因为没有确定本节点是否已经在现有匿名组中了
//自己子树的节点小于
if (childNodeIds.Count < k)
return null;
//如果建组策略为严格的，那么将Ai所在全部匿名组的交集中全部元素为自由节点的框置于Ai所在框后
//if (global.isBuildGroupPolicyStrict == true)
//{
//求Ai所在全部匿名组的交集Gmin(Ai)
//如果存在Gmin(Ai)的子集构成一个框，且框内所有节点为自由的
//检查交集中每一个框
PrivacyReader origReader = (PrivacyReader)global.readers[origId];
HashSet<int> insection = origReader.GetGroupInsection();
//更正1：不是origNode的匿名组交集，而是其所在框的父框，因为该框和与之交换的框都不能跳出父框
//检查父框中所有框，找出全部为自由节点的框，与其后的非全为自由节点的框交换
//更正2：应该还是交集，新的组不能跳出这个交集外
HashSet<Frame> checkFrames = new HashSet<Frame>();
//foreach (int nodeId in insection)
for (int nodeIndex = origFrame.leftbound; nodeIndex <= origFrame.rightbound; )
{
FrameNode node = lnodes[nodeIndex];
//FrameNode node = lnodes[nodeIdIndexMapping[nodeId]];
if (!IsNodeAvailable(node.nodeId))
{
nodeIndex++;
continue;
}
Frame frame = frameIdIndexMapping[node.belongedFrameId];
//属于同一个框，返回
if (node.belongedFrameId == origFrame.frameId)
{
nodeIndex = frame.end + 1;
continue;
}
if (checkFrames.Contains(frame))
continue;
checkFrames.Add(frame);
bool isAllFreeFrame = IsAllFreeFrame(frame, lnodes);
//如果该框全部由自由节点构成
//则将该框与Ai所在框后的第一个非全自由节点的框交换
//自由框可利用的前提是同在一个组内
if (isAllFreeFrame == true && frame.leftbound==origFrame.leftbound && frame.rightbound == origFrame.rightbound)
{
Frame nextNotAllFreeFrame = GetNextNotAllFreeFrame(origFrame, lnodes, lframes, frameIdIndexMapping, origFrame.rightbound);
//两框可交换的前提是其均在同一个组内
if (nextNotAllFreeFrame != null && nextNotAllFreeFrame != origFrame
&& (frame.start - nextNotAllFreeFrame.start) * (nextNotAllFreeFrame.start - origFrame.start) > 0
&& nextNotAllFreeFrame.leftbound == frame.leftbound && nextNotAllFreeFrame.rightbound == frame.rightbound)
{
SwapFrames(nextNotAllFreeFrame, frame, nodeIndexMapping, nodeIdIndexMapping, frameIdIndexMapping, lframes, lnodes);
origIndex = nodeIdIndexMapping[origId];
origNode = lnodes[origIndex];
origFrame = frameIdIndexMapping[origNode.belongedFrameId];
DumpFrames(lframes, lnodes, frameIdIndexMapping, currentId);
}
break;
}
nodeIndex = frame.end + 1;
}
/*}
else//非严格，将前述交集的条件放宽到全集并执行
{
//TODO
}*/
//第三步从Ai开始先左后右依次选择k个元素生成新的框I，将其余元素组成新框II，如果被选择节点与Ai同在一个框内，则其匿名组是一致的，直接将其加入
newgroup.Clear();
int xi = origIndex;
int start = xi;
while (xi >= origFrame.start && newgroup.Count < k)
{
start = xi;
if(IsNodeAvailable(lnodes[xi].nodeId))
newgroup.Add(lnodes[xi].nodeId);
xi--;
}
//还不够，往右走
xi = origIndex;
int end = xi;
while (xi <= origFrame.end && newgroup.Count < k)
{
end = xi;
if (IsNodeAvailable(lnodes[xi].nodeId) && !newgroup.Contains(lnodes[xi].nodeId))
newgroup.Add(lnodes[xi].nodeId);
xi++;
}
//如果在origFrame中还是没有足够的节点，但origFrame后面还有全部为自由节点的框，可与之组合成新组，则也加进来
Frame lastFrame = null;
lastFrame = frameIdIndexMapping[lnodes[end].belongedFrameId];
for (int nodeIndex = origFrame.end + 1; nodeIndex<lnodes.Count&& newgroup.Count < k; )
{
Frame currentFrame = frameIdIndexMapping[lnodes[nodeIndex].belongedFrameId];
//如果两个frame不在同一个父frame中，则放弃
if (currentFrame.parent != lastFrame.parent)
break;
//否则如果非全部是自由节点，放弃
if (IsAllFreeFrame(currentFrame, lnodes) == false
//&& GetAvailFrameNodeCount(currentFrame, lnodes, k)+newgroup.Count<k
)
break;
//否则可添加节点
xi = nodeIndex;
while (xi <= currentFrame.end && newgroup.Count < k)
{
end = xi;
if (IsNodeAvailable(lnodes[xi].nodeId) && !newgroup.Contains(lnodes[xi].nodeId))
newgroup.Add(lnodes[xi].nodeId);
xi++;
}
lastFrame = currentFrame.parent;
nodeIndex = currentFrame.end + 1;
}
//如果第三步不成功，说明原框中没有足够的可用节点，则进行第四步：选择有最多可用元素的框中的一个可用节点与Ai交换，重新执行第二步
if (newgroup.Count < k)
{
if (step == 3)
goto STEP3FAIL;
else if (step == 4)
goto STEP4FAIL;
}
//原始框最左边没有充满，新分出一个框来
if (origFrame.start < start)
{
Frame newframe3 = new Frame(origFrame.start, start - 1);
newframe3.leftbound = origFrame.start;
newframe3.rightbound = origFrame.end;
newframe3.parent = origFrame;
for (int i = origFrame.start; i <= start - 1; i++)
lnodes[i].belongedFrameId = newframe3.frameId;
lframes.Add(newframe3);
lallframes.Add(newframe3);
}
//否则考察右边界
Frame endframe = frameIdIndexMapping[lnodes[end].belongedFrameId];
//如果在原框内，则原框分出两个框来
if (origFrame.end > end)
{
Frame newframe1 = new Frame(start, end);
newframe1.leftbound = origFrame.start;
newframe1.rightbound = origFrame.end;
newframe1.parent = origFrame;
for (int i = newframe1.start; i <= newframe1.end; i++)
lnodes[i].belongedFrameId = newframe1.frameId;
lframes.Add(newframe1);
lallframes.Add(newframe1);
Frame newframe2 = new Frame(end + 1, origFrame.end);
FrameNode nnode = nodes[end];
Frame nframe = frameIdIndexMapping[nnode.belongedFrameId];
newframe2.leftbound = origFrame.start;
newframe2.rightbound = nframe.rightbound;
newframe2.parent = nframe;
for (int i = newframe2.start; i <= newframe2.end; i++)
lnodes[i].belongedFrameId = newframe2.frameId;
lframes.Add(newframe2);
lallframes.Add(newframe2);
lframes.Remove(origFrame);
}
else
{
//否则，原框不变，寻找右边界所在的框，需要新建两个子框
//建立一个虚拟的框，作为新建框的父框
Frame virtualFrame = new Frame(start, end);
virtualFrame.leftbound = endframe.leftbound;
virtualFrame.rightbound = endframe.rightbound;
virtualFrame.parent = endframe.parent;
lallframes.Add(virtualFrame);
//找到虚拟框下面的框，该框需要改变结构
foreach (Frame oframe in lallframes)
{
//如果存在一个框的父节点为虚拟框的父节点，则将其置于虚拟框之下
if (oframe.parent!= null &&
oframe.parent.frameId == endframe.parent.frameId && oframe.frameId != endframe.frameId)
{
oframe.parent = virtualFrame;
oframe.leftbound = virtualFrame.start;
oframe.rightbound = virtualFrame.end;
break;
}
}
//原框作为新框的子框，其边和边界需要变化
for (int j = start; j < end;)
{
FrameNode onode = nodes[j];
Frame oframe = frameIdIndexMapping[onode.belongedFrameId];
if (oframe.end > end)
{
//新纳入的框边界变成
Frame newframe1 = new Frame(oframe.start, end);
newframe1.leftbound = start;
newframe1.rightbound = end;
newframe1.parent = virtualFrame;
for (int i = newframe1.start; i <= newframe1.end; i++)
lnodes[i].belongedFrameId = newframe1.frameId;
lframes.Add(newframe1);
lallframes.Add(newframe1);
//剩下的框边界不变
Frame newframe2 = new Frame(end + 1, oframe.end);
newframe2.leftbound = endframe.leftbound;
newframe2.rightbound = endframe.rightbound;
newframe2.parent = endframe.parent;
for (int i = newframe2.start; i <= newframe2.end; i++)
lnodes[i].belongedFrameId = newframe2.frameId;
lframes.Add(newframe2);
lallframes.Add(newframe2);
lframes.Remove(oframe);
lallframes.Remove(oframe);
}
j = oframe.end + 1;
}
}
DONE:
//重新复制回去
for (int i = 0; i < nodes.Count; i++)
{
nodes[i] = lnodes[i];
}
DumpFrames(lframes, lnodes, currentId);
this.frames = new HashSet<Frame>();
this.allframes = new HashSet<Frame>();
foreach(Frame frame in lframes)
frames.Add(frame);
foreach (Frame frame in lallframes)
allframes.Add(frame);
return newgroup;
//如果第三步不成功，说明原框中没有足够的可用节点，则进行第四步
STEP3FAIL:
//第四步：选择有最多可用元素的框中的一个可用节点与Ai交换，重新执行第二步
step = 4;
Frame mostFreeNodeFrame = FindMostFreeNodeFrame(lnodes[origIndex], lframes);
if (mostFreeNodeFrame == null)
goto STEP4FAIL;
int fnodeIndex = FindAFreeNode(mostFreeNodeFrame);
swapList.Add(lnodes[fnodeIndex].nodeId);
SwapNodes(origIndex, fnodeIndex, lnodes, nodeIndexMapping, nodeIdIndexMapping);
origIndex = nodeIdIndexMapping[origId];
DumpFrames(lframes, lnodes, frameIdIndexMapping, currentId);
goto STEP2;
//第四步不成功，说明Am没有足够多的可用节点构造k-匿名组
STEP4FAIL:
//第五步中将Ai退出所有组，将请求发送给Am的父节点
step = 5;
return null;
}
bool IsAllFreeFrame(Frame frame, List<FrameNode> lnodes)
{
bool isFreeFrame = true;
for (int i = frame.start; i <= frame.end; i++)
{
FrameNode node1 = lnodes[i];
//if (node1.anchor == true && IsNodeAvailable(node1.nodeId))
if (node1.anchor == true)
{
isFreeFrame = false;
break;
}
}
return isFreeFrame;
}
int GetFreeNodes(Frame frame)
{
int fnodes = 0;
for(int i = frame.start;i<frame.end;i++)
{
if(nodes[i].anchor == false)
fnodes ++;
}
return fnodes;
}
int GetAvailFrameNodeCount(Frame frame, List<FrameNode> lnodes, int k)
{
int count = 0;
for (int i = frame.start; i <= frame.end; i++)
{
if (IsNodeAvailable(i))
count++;
}
return count;
}
int FindAFreeNode(Frame frame)
{
for (int i = frame.start; i < frame.end; i++)
{
if (nodes[i].anchor == false)
return i;
}
return -1;
}
public void SwapFrames(Frame frame1, Frame frame2,
Dictionary<FrameNode, int> nodeIndexMapping, Dictionary<int, int> nodeIdIndexMapping,
Dictionary<int, Frame> frameIdIndexMapping, HashSet<Frame> lframes, List<FrameNode> lnodes)
{
if (frame1.frameId == frame2.frameId)
return;
Frame foreframe, backframe = null;
if (frame1.start < frame2.start)
{
foreframe = frame1;
backframe = frame2;
}
else
{
foreframe = frame2;
backframe = frame1;
}
HashSet<Frame> checkedframes = new HashSet<Frame>();
//先把两个frame腾出地方来
List<FrameNode> oforeframe = new List<FrameNode>();
List<FrameNode> obackframe = new List<FrameNode>();
for (int i = foreframe.start; i <= foreframe.end; i++)
oforeframe.Add(lnodes[i]);
for (int i = backframe.start; i <= backframe.end; i++)
obackframe.Add(lnodes[i]);
int forestart = foreframe.start;
int backend = backframe.end;
int forecount = foreframe.end-foreframe.start;
int backcount = backframe.end-backframe.start;
if (forecount<backcount)
{
int offset = backcount - forecount;
for (int i = backframe.start-1; i > foreframe.end; i--)
{
lnodes[i + offset] = lnodes[i];
Frame framex = frameIdIndexMapping[lnodes[i].belongedFrameId];
if (!checkedframes.Contains(framex))
{
checkedframes.Add(framex);
framex.start = framex.start + offset;
framex.end = framex.end + offset;
}
}
}
else
{
int offset = forecount - backcount;
for (int i = foreframe.end+1; i < backframe.start; i++)
{
lnodes[i-offset] = lnodes[i];
Frame framex = frameIdIndexMapping[lnodes[i].belongedFrameId];
if (!checkedframes.Contains(framex))
{
checkedframes.Add(framex);
framex.start = framex.start - offset;
framex.end = framex.end - offset;
}
}
}
//DumpNodes();
//将前面的框放到后面
for (int i = backframe.end-forecount, j = 0; i <= backframe.end; i++, j++)
{
lnodes[i] = oforeframe[j];
}
//DumpNodes();
//将后面的框放到前面
for (int i = foreframe.start, j = 0; i <= foreframe.start+backcount; i++, j++)
{
lnodes[i] = obackframe[j];
}
//DumpNodes();
//新的框的起始位置
foreframe.start = backend - (oforeframe.Count - 1);
foreframe.end = backend;
backframe.start = forestart;
backframe.end = forestart + (obackframe.Count - 1);
//update indexes
for (int i = 0; i < lnodes.Count; i++)
{
FrameNode tnode = lnodes[i];
nodeIndexMapping[tnode] = i;
nodeIdIndexMapping[tnode.nodeId] = i;
}
}
public void Init(HashSet<int> list, int initNodeId, bool IsStrictPolicy)
{
Frame newFrame = new Frame(0, list.Count-1);
this.frames.Add(newFrame);
this.allframes.Add(newFrame);
this.nodes.Add(new FrameNode(initNodeId, true, newFrame.frameId));
foreach (int nodeId in list)
{
if(nodeId != initNodeId)
this.nodes.Add(new FrameNode(nodeId, false, newFrame.frameId));
}
this.IsStrictPolicy = IsStrictPolicy;
}
public Frame GetNextNotAllFreeFrame(Frame frame, List<FrameNode> lnodes, HashSet<Frame> lframes,
Dictionary<int, Frame> frameIdIndexMapping, int rightbound)
{
if (frame.end + 1 >= lnodes.Count)
return null;
int leftbound = frame.end + 1;
int currentindex = leftbound;
while(currentindex<=rightbound)
{
FrameNode node = lnodes[currentindex];
Frame nframe = frameIdIndexMapping[node.belongedFrameId];
bool isAllFreeFrame = IsAllFreeFrame(frame, lnodes);
if (!isAllFreeFrame)
return nframe;
currentindex = nframe.end + 1;
continue;
}
return null;
}
public object Clone()
{
Frame newFrame = new Frame(this.start, this.end, this.leftbound, this.rightbound, this.parent, this.frameId);
return newFrame;
}
