python调用c++ ctype list传数组或者返回数组的方法

Python  /  管理员 发布于 7年前   249

示例1：

pycallclass.cpp：

#include <iostream>using namespace std;typedef unsigned char BYTE;#define MAX_COUNT 20 struct tagOutCardResult_py{BYTEcbCardCount;BYTEcbResultCard1;BYTEcbResultCard2;BYTEcbResultCard3;BYTEcbResultCard4;BYTEcbResultCard5;BYTEcbResultCard6;BYTEcbResultCard7;BYTEcbResultCard8;BYTEcbResultCard9;BYTEcbResultCard10;BYTEcbResultCard11;BYTEcbResultCard12;BYTEcbResultCard13;BYTEcbResultCard14;BYTEcbResultCard15;BYTEcbResultCard16;BYTEcbResultCard17;BYTEcbResultCard18;BYTEcbResultCard19;BYTEcbResultCard20;}; struct tagOutCardResult{BYTEcbCardCount;BYTEcbResultCard[MAX_COUNT];void clear(){cbCardCount = 0;for (int nIdx = 0;nIdx < MAX_COUNT;++nIdx){cbResultCard[nIdx] = 0;}}void topy(tagOutCardResult_py* ppy){cout<<"topy function begin"<<endl;ppy->cbCardCount = cbCardCount;cout<<"topy function 1"<<endl;ppy->cbResultCard1 = cbResultCard[1 - 1];cout<<"topy function 2"<<endl;ppy->cbResultCard2 = cbResultCard[2 - 1];ppy->cbResultCard3 = cbResultCard[3 - 1];ppy->cbResultCard4 = cbResultCard[4 - 1];ppy->cbResultCard5 = cbResultCard[5 - 1];ppy->cbResultCard6 = cbResultCard[6 - 1];ppy->cbResultCard7 = cbResultCard[7 - 1];ppy->cbResultCard8 = cbResultCard[8 - 1];ppy->cbResultCard9 = cbResultCard[9 - 1];ppy->cbResultCard10 = cbResultCard[10 - 1];ppy->cbResultCard11 = cbResultCard[11 - 1];ppy->cbResultCard12 = cbResultCard[12 - 1];ppy->cbResultCard13 = cbResultCard[13 - 1];ppy->cbResultCard14 = cbResultCard[14 - 1];ppy->cbResultCard15 = cbResultCard[15 - 1];ppy->cbResultCard16 = cbResultCard[16 - 1];ppy->cbResultCard17 = cbResultCard[17 - 1];ppy->cbResultCard18 = cbResultCard[18 - 1];ppy->cbResultCard19 = cbResultCard[19 - 1];ppy->cbResultCard20 = cbResultCard[20 - 1];cout<<"topy function end"<<endl;}}; class TestLib{public:void display(tagOutCardResult& ret);};void TestLib::display(tagOutCardResult& ret) {ret.cbCardCount = 3;ret.cbResultCard[0] = 1;ret.cbResultCard[1] = 50;ret.cbResultCard[2] = 100; cout<<"First display aaa ";cout<<"hello ";cout<<"world ";} extern "C" {TestLib oGameLogic;void display(tagOutCardResult_py* ret_py) {tagOutCardResult oRet;oGameLogic.display(oRet);cout<<"before topy"<<endl;oRet.topy(ret_py);cout<<"after topy"<<endl;cout<<"in cpp:ret_py->cbCardCount:"<<ret_py->cbCardCount<<endl;cout<<"in cpp:ret_py->cbResultCard1:"<<ret_py->cbResultCard1<<endl;cout<<" this:" << ret_py << endl;}} 

编译脚本：

g++ -o libpycallclass.so -shared -fPIC pycallclass.cpp -I/usr/include/python2.6 -L/usr/lib64/python2.6/config

Game.py调用部分。类声明：

import ctypes class tagOutCardResult_py(ctypes.Structure): _fields_ = [("cbCardCount", ctypes.c_ubyte), \("cbResultCard1", ctypes.c_ubyte), \("cbResultCard2", ctypes.c_ubyte), \("cbResultCard3", ctypes.c_ubyte), \("cbResultCard4", ctypes.c_ubyte), \("cbResultCard5", ctypes.c_ubyte), \("cbResultCard6", ctypes.c_ubyte), \("cbResultCard7", ctypes.c_ubyte), \("cbResultCard8", ctypes.c_ubyte), \("cbResultCard9", ctypes.c_ubyte), \("cbResultCard10", ctypes.c_ubyte), \("cbResultCard11", ctypes.c_ubyte), \("cbResultCard12", ctypes.c_ubyte), \("cbResultCard13", ctypes.c_ubyte), \("cbResultCard14", ctypes.c_ubyte), \("cbResultCard15", ctypes.c_ubyte), \("cbResultCard16", ctypes.c_ubyte), \("cbResultCard17", ctypes.c_ubyte), \("cbResultCard18", ctypes.c_ubyte), \("cbResultCard19", ctypes.c_ubyte), \("cbResultCard20", ctypes.c_ubyte)]

Game.py调用部分。具体调用：

  import ctypes  so = ctypes.cdll.LoadLibrary  lib = so("./libpycallclass.so")  ERROR_MSG('display(\)')  ret = tagOutCardResult_py(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)  ERROR_MSG("before lib.display(ctypes.byref(ret))")  lib.display(ctypes.byref(ret))  ERROR_MSG("after lib.display(ctypes.byref(ret))")  ERROR_MSG('#######################################################################################')  ERROR_MSG(ret)  ERROR_MSG(ret.cbCardCount)  ERROR_MSG(ret.cbResultCard1)  ERROR_MSG(ret.cbResultCard2)  ERROR_MSG(ret.cbResultCard3)  ERROR_MSG(type(ret))

传入一个结构体，使用引用返回，回到python中打印出来结果是对的。

这样就可以传入，可以传出了。

示例1end#########################################################################

示例2：

pycallclass.cpp:

#include <iostream>using namespace std;typedef unsigned char BYTE;#define MAX_COUNT 20 #if defined(WIN32)||defined(WINDOWS)#define DLL_EXPORT __declspec(dllexport)#else#define DLL_EXPORT#endif struct ByteArray_20{BYTE e1;BYTE e2;BYTE e3;BYTE e4;BYTE e5;BYTE e6;BYTE e7;BYTE e8;BYTE e9;BYTE e10;BYTE e11;BYTE e12;BYTE e13;BYTE e14;BYTE e15;BYTE e16;BYTE e17;BYTE e18;BYTE e19;BYTE e20;};struct ByteArray_20_3{ByteArray_20 e1;ByteArray_20 e2;ByteArray_20 e3;}; struct ByteArrayNew_20_3{BYTE e[3][20];}; class TestLib{public:void LogicFunc(ByteArray_20_3& ret);void LogicFuncNew(ByteArrayNew_20_3& ret);};void TestLib::LogicFunc(ByteArray_20_3& ret) {ret.e1.e1 = 3;ret.e1.e2 = 1;ret.e1.e3 = 50;ret.e2.e1 = 100;ret.e2.e2 = 200;ret.e2.e3 = 20; cout<<"TestLib::LogicFunc"<<endl;}void TestLib::LogicFuncNew(ByteArrayNew_20_3& ret) {ret.e[0][0] = 31;ret.e[0][1] = 11;ret.e[0][2] = 51;ret.e[1][0] = 101;ret.e[1][1] = 201;ret.e[1][2] = 21; cout << "TestLib::LogicFuncNew" << endl;} extern "C" {TestLib oGameLogic;void DLL_EXPORT display(ByteArray_20_3* pret) {cout<<"cpp display func begin"<<endl;oGameLogic.LogicFunc(*pret);cout<<"cpp display func end"<<endl;}void DLL_EXPORT display2(ByteArrayNew_20_3* pret) {cout << "cpp display2 func begin" << endl;oGameLogic.LogicFuncNew(*pret);cout << "cpp display2 func end" << endl;}}

pycallclass.py:

import ctypes def ERROR_MSG(str): print str class ByteArray_20(ctypes.Structure): _fields_ = [\("e1", ctypes.c_ubyte), \("e2", ctypes.c_ubyte), \("e3", ctypes.c_ubyte), \("e4", ctypes.c_ubyte), \("e5", ctypes.c_ubyte), \("e6", ctypes.c_ubyte), \("e7", ctypes.c_ubyte), \("e8", ctypes.c_ubyte), \("e9", ctypes.c_ubyte), \("e10", ctypes.c_ubyte), \("e11", ctypes.c_ubyte), \("e12", ctypes.c_ubyte), \("e13", ctypes.c_ubyte), \("e14", ctypes.c_ubyte), \("e15", ctypes.c_ubyte), \("e16", ctypes.c_ubyte), \("e17", ctypes.c_ubyte), \("e18", ctypes.c_ubyte), \("e19", ctypes.c_ubyte), \("e20", ctypes.c_ubyte)]  class ByteArray_20_3(ctypes.Structure): _fields_ = [\("e1", ByteArray_20), \("e2", ByteArray_20), \("e3", ByteArray_20)] def __init__(self):  self.aaa = 123  self.bbb = [1, 2, 3, 4, 5]  self.ccc = "alksdfjlasdfjk" def test(self):  self.aaa = 123  self.bbb = [1, 2, 3, 4, 5]  self.ccc = "alksdfjlasdfjk"  self.e1.e1 = 5  self.e1.e2 = 20  so = ctypes.cdll.LoadLibrarylib = so("./libpycallclass.dll")print('display()')ret = ByteArray_20_3()ret.test()ERROR_MSG(ret.e1.e1)ERROR_MSG(ret.e1.e2)print("before lib.display(ctypes.byref(ret))")lib.display(ctypes.byref(ret))print("after lib.display(ctypes.byref(ret))")print('#######################################################################################')print(ret)ERROR_MSG(ret.e1)ERROR_MSG(ret.e2)ERROR_MSG(ret.e3)ERROR_MSG(ret.e1.e1)ERROR_MSG(ret.e1.e2)ERROR_MSG(ret.e1.e3)ERROR_MSG(ret.e2.e1)ERROR_MSG(ret.e2.e2)ERROR_MSG(ret.e2.e3)ERROR_MSG(type(ret)) print("before lib.display2(ctypes.byref(ret))")lib.display2(ctypes.byref(ret))print("after lib.display2(ctypes.byref(ret))")print('#######################################################################################')print(ret)ERROR_MSG(ret.e1)ERROR_MSG(ret.e2)ERROR_MSG(ret.e3)ERROR_MSG(ret.e1.e1)ERROR_MSG(ret.e1.e2)ERROR_MSG(ret.e1.e3)ERROR_MSG(ret.e2.e1)ERROR_MSG(ret.e2.e2)ERROR_MSG(ret.e2.e3)ERROR_MSG(type(ret)) ret.test()ERROR_MSG(ret.e1.e1)ERROR_MSG(ret.e1.e2)

g++:

g++ -o libpycallclass.so -shared -fPIC pycallclass.cpp -I/usr/include/python2.6 -L/usr/lib64/python2.6/config

windows:

新建一个DLL工程，把pycallclass.cpp加进去，编译成DLL就OK了。

千万注意python的运行时是32位的还是64位的，DLL或者SO必须和它对应。

python类可以嵌套使用，继承ctypes.Structure，部分成员是_fields_里定义的，部分成员在__init__里定义，这样的类也可以ctypes.byref(self)传进c++去，传的是指针，传入传出就都OK了。

注意示例2中ByteArrayNew_20_3的用法，python中是定义了20个变量，c++中是直接一个二维数组。内存结构是一致的，所以可以直接这样使用。注意类型和长度必须一致，否则可能会内存访问越界。

以上这篇python调用c++ ctype list传数组或者返回数组的方法就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。