c++ - Clang AST 访问者，避免遍历包含文件

Question

你好，我正在尝试实现一个 AST Clang 访问者，这是我的代码。

class ExampleVisitor : public RecursiveASTVisitor<ExampleVisitor> {
private:
    ASTContext *astContext; // used for getting additional AST info

public:
    virtual bool VisitVarDecl(VarDecl *var) 
    {
        numVariables++;
        string varName = var->getQualifiedNameAsString();
        string varType = var->getType().getAsString();
        cout << "Found variable declaration: " << varName << " of type " << varType << "\n";
        APIs << varType << ", ";
        return true;
    }

    virtual bool VisitFunctionDecl(FunctionDecl *func)
    {
        numFunctions++;
        string funcName = func->getNameInfo().getName().getAsString();
        string funcType = func->getResultType().getAsString();
        cout << "Found function declaration: " << funcName << " of type " << funcType << "\n";
        APIs << "\n\n" << funcName <<": ";
        APIs << funcType << ", ";
        return true;
    }

    virtual bool VisitStmt(Stmt *st) 
    {
        if (CallExpr *call = dyn_cast<CallExpr>(st)) 
        {
            numFuncCalls++;
            FunctionDecl *func_decl = call->getDirectCallee();
            string funcCall = func_decl->getNameInfo().getName().getAsString();
            cout << "Found function call: " << funcCall << " with arguments ";
            APIs << funcCall << ", ";
            for(int i=0, j = call->getNumArgs(); i<j; i++)
            {
                string TypeS;
                raw_string_ostream s(TypeS);
                call->getArg(i)->printPretty(s, 0, Policy);
                cout<< s.str() << ", ";
                APIs<< s.str() << ", ";
           }
            cout << "\n";
        }
        return true;
    }
};

如何避免遍历包含的头文件，但又不丢失它们的信息。我只是不想打印有关此文件的任何信息，但我希望 clang 知道这些文件

谢谢

Answer 1

通过使用 AST 上下文，您可以获得正在解析的代码的所有必需信息。区分主文件或头文件中的 AST 节点的函数称为 isInMainFile()，可以按如下方式使用。

bool VisitVarDecl(VarDecl *var)
{
    if (astContext->getSourceManager().isInMainFile(var->getLocStart())) //checks if the node is in the main = input file.
    {
        if(var->hasLocalStorage() || var->isStaticLocal())
        {
            //var->dump(); //prints the corresponding line of the AST.
            FullSourceLoc FullLocation = astContext->getFullLoc(var->getLocStart());
            numVariables++;
            string varName = var->getQualifiedNameAsString();
            string varType = var->getType().getAsString();
            REPORT << "Variable Declaration [" << FullLocation.getSpellingLineNumber() << "," << FullLocation.getSpellingColumnNumber() << "]: " << varName << " of type " << varType << "\n";
            APIs << varType << ",";
        }
    }
    return true;
}

有关如何使用 astContext 的更多信息，请参阅 clang 网站上的官方递归 ASTvisitor 教程。