Python是解釋性語言, 底層就是用c實(shí)現(xiàn)的, 所以用python調(diào)用C是很容易的, 下面就總結(jié)一下各種調(diào)用的方法, 給出例子, 所有例子都在ubuntu9.10, python2.6下試過.

1. Python 調(diào)用 C (base)

想在python中調(diào)用c函數(shù), 如這兒的fact

#include <Python.h>

int fact(int n)
{
 if (n <= 1)
 return 1;
 else
 return n * fact(n - 1);
}

PyObject* wrap_fact(PyObject* self, PyObject* args)
{
 int n, result;

 if (! PyArg_ParseTuple(args, "i:fact", &n))
 return NULL;
 result = fact(n);
 return Py_BuildValue("i", result);
}

static PyMethodDef exampleMethods[] =
{
 {"fact", wrap_fact, METH_VARARGS, "Caculate N!"},
 {NULL, NULL}
};

void initexample()
{
 PyObject* m;
 m = Py_InitModule("example", exampleMethods);
}

把這段代碼存為wrapper.c, 編成so庫,

gcc -fPIC wrapper.c -o example.so -shared  -I/usr/include/python2.6 -I/usr/lib/python2.6/config

 然后在有此so庫的目錄, 進(jìn)入python, 可以如下使用

import example

example.fact(4)

2. Python 調(diào)用 C++ (base)

在python中調(diào)用C++類成員函數(shù), 如下調(diào)用TestFact類中的fact函數(shù),

#include <Python.h>

class TestFact{
 public:
 TestFact(){};
 ~TestFact(){};
 int fact(int n);
};

int TestFact::fact(int n)
{
 if (n <= 1)
 return 1;
 else
 return n * (n - 1);
}

int fact(int n)
{
 TestFact t;
 return t.fact(n);
}

PyObject* wrap_fact(PyObject* self, PyObject* args)
{
 int n, result;

 if (! PyArg_ParseTuple(args, "i:fact", &n))
 return NULL;
 result = fact(n);
 return Py_BuildValue("i", result);
}

static PyMethodDef exampleMethods[] =
{
 {"fact", wrap_fact, METH_VARARGS, "Caculate N!"},
 {NULL, NULL}
};

extern "C"    //不加會導(dǎo)致找不到initexample
void initexample()
{
 PyObject* m;
 m = Py_InitModule("example", exampleMethods);
}

 把這段代碼存為wrapper.cpp, 編成so庫,

g++ -fPIC wrapper.cpp -o example.so -shared -I/usr/include/python2.6 -I/usr/lib/python2.6/config

 然后在有此so庫的目錄, 進(jìn)入python, 可以如下使用

import example

example.fact(4)

 3. Python 調(diào)用 C++ (Boost.Python)

Boost庫是非常強(qiáng)大的庫, 其中的python庫可以用來封裝c++被python調(diào)用, 功能比較強(qiáng)大, 不但可以封裝函數(shù)還能封裝類, 類成員.

http://dev.gameres.com/Program/Abstract/Building%20Hybrid%20Systems%20with%20Boost_Python.CHN.by.JERRY.htm

首先在ubuntu下安裝boost.python, apt-get install libboost-python-dev

#include <boost/python.hpp>
char const* greet()
{
 return "hello, world";
}

BOOST_PYTHON_MODULE(hello)
{
 using namespace boost::python;
 def("greet", greet);
}

把代碼存為hello.cpp, 編譯成so庫

g++ hello.cpp -o hello.so -shared -I/usr/include/python2.5 -I/usr/lib/python2.5/config -lboost_python-gcc42-mt-1_34_1

 此處python路徑設(shè)為你的python路徑, 并且必須加-lboost_python-gcc42-mt-1_34_1, 這個庫名不一定是這個, 去/user/lib查

 然后在有此so庫的目錄, 進(jìn)入python, 可以如下使用

>>> import hello
>>> hello.greet()
'hello, world'

 4. python 調(diào)用 c++ (ctypes)

ctypes is an advanced ffi (Foreign Function Interface) packagefor Python 2.3 and higher. In Python 2.5 it is alreadyincluded.

ctypes allows to call functions in dlls/shared libraries and hasextensive facilities to create, access and manipulate simple andcomplicated C data types in Python - in other words: wraplibraries in pure Python. It is even possible to implement Ccallback functions in pure Python.

http://python.net/crew/theller/ctypes/

 

#include <Python.h>

class TestFact{
 public:
 TestFact(){};
 ~TestFact(){};
 int fact(int n);
};

int TestFact::fact(int n)
{
 if (n <= 1)
 return 1;
 else
 return n * (n - 1);
}

extern "C"
int fact(int n)
{
 TestFact t;
 return t.fact(n);
}

將代碼存為wrapper.cpp不用寫python接口封裝, 直接編譯成so庫,

g++ -fPIC wrapper.cpp -o example.so -shared -I/usr/include/python2.6 -I/usr/lib/python2.6/config

 進(jìn)入python, 可以如下使用

>>> import ctypes
>>> pdll = ctypes.CDLL('/home/ubuntu/tmp/example.so')
>>> pdll.fact(4)
12

到此這篇關(guān)于Python調(diào)用C/C++的方法解析的文章就介紹到這了,更多相關(guān)Python調(diào)用C/C++的方法內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家！