Question

我有一个包含（Poco）互斥锁的C ++类：

class ClassWithMutex
{
    public:
                                ClassWithMutex();
        virtual                 ~ClassWithMutex();

        Poco::Mutex             mMyMutex;

    private:
        ClassWithMutex(const ClassWithMutex& );
        ClassWithMutex& operator=(const ClassWithMutex& other);

};

另一个类，使用它：

class ClassHavingAClassWithMutex
{
    public:
        ClassHavingAClassWithMutex();
        ~ClassHavingAClassWithMutex();
        ClassWithMutex      A;

    private:
        ClassHavingAClassWithMutex(const ClassHavingAClassWithMutex&);
        ClassHavingAClassWithMutex& ClassHavingAClassWithMutex::operator=(const ClassHavingAClassWithMutex& other);

};

当尝试为ClassHavingAClassWithMutex创建包装时，出现错误：

Error   C2248   'ClassWithMutex::operator =': cannot access private member declared in class 'ClassWithMutex'   mvr C:\builds\vs2015\mvr\python_package\src\mvr\mvrPYTHON_wrap.cxx  6493

Swig生成的代码如下：

SWIGINTERN PyObject *_wrap_ClassWithMutex_mMyMutex_get(PyObject *SWIGUNUSEDPARM(self), PyObject *args) {
  PyObject *resultobj = 0;
  ClassWithMutex *arg1 = (ClassWithMutex *) 0 ;
  void *argp1 = 0 ;
  int res1 = 0 ;
  PyObject *swig_obj[1] ;
  Poco::Mutex result;

  if (!args) SWIG_fail;
  swig_obj[0] = args;
  res1 = SWIG_ConvertPtr(swig_obj[0], &argp1,SWIGTYPE_p_ClassWithMutex, 0 |  0 );
  if (!SWIG_IsOK(res1)) {
    SWIG_exception_fail(SWIG_ArgError(res1), "in method '" "ClassWithMutex_mMyMutex_get" "', argument " "1"" of type '" "ClassWithMutex *""'"); 
  }
  arg1 = reinterpret_cast< ClassWithMutex * >(argp1);
  {
    SWIG_PYTHON_THREAD_BEGIN_ALLOW;
    result =  ((arg1)->mMyMutex);
    SWIG_PYTHON_THREAD_END_ALLOW;
  }
  resultobj = SWIG_NewPointerObj((new Poco::Mutex(static_cast< const Poco::Mutex& >(result))), SWIGTYPE_p_Poco__Mutex, SWIG_POINTER_OWN |  0 );
  return resultobj;
fail:
  return NULL;
}

以及此行发出的错误：

if (arg1) (arg1)->A = *arg2;
and
resultobj = SWIG_NewPointerObj((new Poco::Mutex(static_cast< const Poco::Mutex& >(result))), SWIGTYPE_p_Poco__Mutex, SWIG_POINTER_OWN |  0 );

Swig接口文件：

%immutable
%include "aiClassWithMutex.h"
%include "ClassHavingAClassWithMutex.h"
%mutable

关于如何使用Swig正确包装以上类的任何建议？为了防止任何复制，我在上面的类中将复制和分配ctor设为私有，但似乎仍然坚持？

Answer 1

这不是由复制构造函数引起的，而是属性设置器（b / c A是公共的）引起的。如评论中所述，一种选择是通过添加以下内容来隐藏它：

%ignore ClassWithMutex::mMyMutex;

.i文件中%include "aiClassWithMutex.h"之前。

如前所述，SWIG在使mMyMutex不变的情况下也采用复制方式。 AFAICT，除了编写类型映射并滥用optimal设置（首先是防止构造临时文件）之外，没有其他方法。这样，可以正常运行的.i文件如下：

%module mut

%{  
#include "aiClassWithMutex.h"
#include "ClassHavingAClassWithMutex.h"
%}      

%feature("immutable", 1) ClassWithMutex::mMyMutex;
%typemap(out, optimal="1") Poco::Mutex %{
  $result = SWIG_NewPointerObj(($1_ltype*)&$1, $&1_descriptor, 0);
%}      
%include "aiClassWithMutex.h"
%include "ClassHavingAClassWithMutex.h"

使用Swig在成员中使用互斥体包装C ++类时出现问题

1 个答案: