阅读the documentation告诉我，clang_visitChildren只会“返回”指向返回CXChildVisit_Recurse所指向的内容。因此，您的访问函数应检查游标的种类并返回CXChildVisit_Continue，直到到达名称等于main的函数定义为止。 main的作用由您决定，但我建议返回CXChildVisit_Break。

因此，感谢Botje和本文（https://www.phototalks.idv.tw/academic/?p=1932），我找到了解决方案。无论如何，这都不是最好的代码，但是它可以工作。希望对其他人有帮助。

#include <iostream>
#include <clang-c/Index.h>
#include <string.h>
using namespace std;

ostream& operator<<(ostream& stream,const CXString& str)
{
  stream << clang_getCString(str);
  clang_disposeString(str);
  return stream;
}

std::string getCursorKindName( CXCursorKind cursorKind )
{
  CXString kindName  = clang_getCursorKindSpelling( cursorKind );
  std::string result = clang_getCString( kindName );

  clang_disposeString( kindName );
  return result;
}

std::string getCursorSpelling( CXCursor cursor )
{
  CXString cursorSpelling = clang_getCursorSpelling( cursor );
  std::string result      = clang_getCString( cursorSpelling );

  clang_disposeString( cursorSpelling );
  return result;
}
CXChildVisitResult visitor1( CXCursor cursor,CXCursor /* parent */,CXClientData clientData )
{
  CXSourceLocation location = clang_getCursorLocation( cursor );
    unsigned int locationstring =0;
     clang_getSpellingLocation  (   location,NULL,&locationstring,NULL);
  if( clang_Location_isFromMainFile( location ) == 0 )
    return CXChildVisit_Continue;
  CXCursorKind kind = clang_getCursorKind(cursor);
    std::string str2 ("main");
  CXCursorKind cursorKind = clang_getCursorKind( cursor );
  unsigned int curLevel  = *( reinterpret_cast<unsigned int*>( clientData ) );
  unsigned int nextLevel = curLevel + 1;
    std::cout << std::string( curLevel,'-' ) << " " << getCursorKindName(
    cursorKind ) << " (" << getCursorSpelling( cursor ) << ") ";
    std::cout << locationstring ;
    std::cout << endl;

    clang_visitChildren( cursor,visitor1,&nextLevel );
    return CXChildVisit_Continue;

}

CXChildVisitResult visitor( CXCursor cursor,CXClientData clientData )
{
  CXSourceLocation location = clang_getCursorLocation( cursor );
  if( clang_Location_isFromMainFile( location ) == 0 )
    return CXChildVisit_Continue;
  CXCursorKind kind = clang_getCursorKind(cursor);
    std::string str2 ("main");
  CXCursorKind cursorKind = clang_getCursorKind( cursor );

  unsigned int curLevel  = *( reinterpret_cast<unsigned int*>( clientData ) );
  unsigned int nextLevel = curLevel + 1;
  if (!((str2.compare(getCursorSpelling(cursor)))))
  {
    std::cout << std::string( curLevel,'-' ) << " " << getCursorKindName(
    cursorKind ) << " (" << getCursorSpelling( cursor ) << ")\n";

    clang_visitChildren( cursor,&nextLevel );
    return CXChildVisit_Continue;
  }
  else
  {
  return CXChildVisit_Continue;
  }
}

int main()
{
  CXIndex index = clang_createIndex(0,0);
  CXTranslationUnit unit = clang_parseTranslationUnit(
     index,<source_file_name>,nullptr,CXTranslationUnit_None);
      CXCursor cursor = clang_getTranslationUnitCursor(unit);
      unsigned int treeLevel = 0;
      clang_visitChildren( cursor,visitor,&treeLevel );
  clang_disposeTranslationUnit(unit);
  clang_disposeIndex(index);
}