/// TODO: Checking aliases of the two variables at source and sink. For example: /// src instruction: actualRet = source(); /// snk instruction: sink(actualParm,...); /// return true if actualRet is aliased with any parameter at the snk node (e.g., via ander->alias(..,..)) bool TaintGraphTraversal::aliasCheck(const CallICFGNode *src, const CallICFGNode *snk) { }

这段代码中有一个TODO标记，表示这是需要完成的一个任务。具体来说，这个任务是检查源节点和汇节点中两个变量的别名关系。例如，源指令可能是 `actualRet = source();` ，汇指令可能是 `sink(actualParm,...);` ，如果 `actualRet` 与汇节点中的任何一个参数存在别名关系，则返回true。在实现这个任务时，需要使用 `ander->alias(..,..)` 函数进行别名检查。

相关问题

/// TODO: print each path once this method is called, and /// (1) add each path (a sequence of node IDs) as a string into std::set<std::string> paths /// in the format "START: 1->2->4->5->END", where -> indicate an ICFGEdge connects two ICFGNode IDs /// bonus: dump and append each program path to a `ICFGPaths.txt` in the form of /// ‘{ln: number cl: number, fl:name} -> {ln: number, cl: number, fl: name} -> {ln:number, cl: number, fl: name} /// ln : line number cl: column number fl:file name for further learning, you can review the code in SVF, SVFUtil void TaintGraphTraversal::printICFGPath(std::vector<const ICFGNode *> &path){ } // TODO: Implement your code to parse the two lines from `SrcSnk.txt` in the form of // line 1 for sources "{ api1 api2 api3 }" // line 2 for sinks "{ api1 api2 api3 }" void TaintGraphTraversal::readSrcSnkFromFile(const string& filename){ } /// TODO: Checking aliases of the two variables at source and sink. For example: /// src instruction: actualRet = source(); /// snk instruction: sink(actualParm,...); /// return true if actualRet is aliased with any parameter at the snk node (e.g., via ander->alias(..,..)) bool TaintGraphTraversal::aliasCheck(const CallICFGNode *src, const CallICFGNode *snk) { return true; } 这三个空分别应该填什么代码

第一个空：

void TaintGraphTraversal::printICFGPath(std::vector<const ICFGNode *> &path){
    std::stringstream ss;
    ss << "START: ";
    for(auto node: path){
        ss << node->getId();
        if(node->getOutDegree() > 0){
            ss << "->";
        }
    }
    ss << "END";
    std::string pathStr = ss.str();
    paths.insert(pathStr);
    std::ofstream file("ICFGPaths.txt", std::ios_base::app);
    if(file.is_open()){
        file << "{ln:" << path.front()->getInst()->getLine() 
             << " cl:" << path.front()->getInst()->getColumn() 
             << " fl:" << path.front()->getInst()->getFilename() << "}";
        for(auto node: path){
            file << " -> ";
            file << "{ln:" << node->getInst()->getLine() 
                 << " cl:" << node->getInst()->getColumn() 
                 << " fl:" << node->getInst()->getFilename() << "}";
        }
        file << "\n";
        file.close();
    }
}

第二个空：

void TaintGraphTraversal::readSrcSnkFromFile(const string& filename){
    std::ifstream file(filename);
    if(file.is_open()){
        std::string line1, line2;
        std::getline(file, line1);
        std::getline(file, line2);
        std::regex re("\\{([^\\}]*)\\}");
        std::smatch match;
        std::vector<std::string> srcVec, snkVec;
        while(std::regex_search(line1, match, re)){
            srcVec.push_back(match[1]);
            line1 = match.suffix().str();
        }
        while(std::regex_search(line2, match, re)){
            snkVec.push_back(match[1]);
            line2 = match.suffix().str();
        }
        file.close();
    }
}

第三个空：

bool TaintGraphTraversal::aliasCheck(const CallICFGNode *src, const CallICFGNode *snk) {
    const SVFFunction *srcFunc = src->getCallee();
    const SVFFunction *snkFunc = snk->getCallee();
    const SVFVariable *retVar = srcFunc->getRetVar();
    std::vector<const SVFVariable *> paramVars = snkFunc->getParamVars();
    for(auto paramVar: paramVars){
        if(paramVar->alias(retVar)){
            return true;
        }
    }
    return false;
}

for(auto i: list){ list.remove(i); //TODO: Error 3 : why? }

这段代码尝试通过`for-each`循环遍历并移除`list`中的元素，但可能会遇到错误。因为`remove()`操作会改变集合的大小，而Java `for-each`循环并不支持在迭代过程中修改集合的元素。这被称为"mutable collection"的陷阱[^1]。

正确的做法是使用迭代器（iterator）来逐个处理元素，如示例所示[^1]:

Iterator<Integer> it = list.iterator();
while (it.hasNext()) {
    Integer value = it.next();
    if (value == 5) {
        it.remove();  // 使用迭代器的remove()方法
    }
}

或者使用更安全的并发工具，如`CopyOnWriteArrayList`，这样可以直接从`list`中移除元素而不影响迭代：

List<Integer> copyOnWriteList = Collections.synchronizedList(new CopyOnWriteArrayList<>());
// ... 添加元素
copyOnWriteList.removeIf(value -> value == 5);