用C语言实现python的扩展模块

用C语言实现python的扩展模块

示例1：

1 Example.c

int add(int a,int b)

{

return a+b;

}

int sub(int a,int b)

{

return a -b;

}

int mul(int a,int b)

{

return a*b;

}

int div1(int a,int b)

{

if(0 == b)

{

return b;

}

return a/b;

}

2 wrap.c

#include <Python.h> //python.h中已经包含了常用的头文件

PyObject* wrap_add(PyObject* self, PyObject* args)

{

int n1,n2, result;

if (! PyArg_ParseTuple(args, "i|i", &n1,&n2))

return NULL;

result = add(n1,n2);

return Py_BuildValue("i", result);

}

PyObject* wrap_sub(PyObject* self, PyObject* args)

{

int n1,n2, result;

if (! PyArg_ParseTuple(args, "i|i", &n1,&n2))

return NULL;

result = sub(n1,n2);

return Py_BuildValue("i", result);

}

PyObject* wrap_mul(PyObject* self, PyObject* args)

{

int n1,n2, result;

if (! PyArg_ParseTuple(args, "i|i", &n1,&n2))

return NULL;

result = mul(n1,n2);

return Py_BuildValue("i", result);

}

PyObject* wrap_div1(PyObject* self, PyObject* args)

{

int n1,n2, result;

if (! PyArg_ParseTuple(args, "i|i", &n1,&n2))

return NULL;

result = div1(n1,n2);

return Py_BuildValue("i", result);

}

static PyMethodDef exampleMethods[] =

{

{"add", wrap_add, METH_VARARGS, "Caculate 1!"},

{"sub", wrap_sub, METH_VARARGS, "Caculate 2!"},

{"mul", wrap_mul, METH_VARARGS, "Caculate 3!"},

{"div1", wrap_div1, METH_VARARGS, "Caculate 4!"},

{NULL, NULL,0,NULL}

};

void initexample()

{

PyObject* m;

m = Py_InitModule("example", exampleMethods);

}

3 编译

gcc -fpic -c -I /usr/include/python2.6/ -I /usr/lib/python2.6/config example.c wrap.c

gcc -shared -o wrap.so wrap.o

4 功能演示截图

5 主要参考：

5．1 Python的C语言扩展
http://www.ibm.com/developerworks/cn/linux/l-pythc/
5．2 浅谈 Python 程序和 C 程序的整合
http://www.ibm.com/developerworks/cn/linux/l-cn-pythonandc/index.html?ca=drs-cn-0506
示例2：（支持回调python中定义的函数）

1 mytest.c

#include <Python.h>

static PyObject *my_callback = NULL;

static PyObject* my_strlen(PyObject *self, PyObject *args)

{

char *string;

int len;

if (!PyArg_ParseTuple(args, "s", &string))

return NULL;

len = strlen(string);

return Py_BuildValue("i", len);

}

static PyObject* my_strcat(PyObject *self, PyObject *args)

{

char* string1;

char* string2;

char* newstring;

if (!PyArg_ParseTuple(args, "s|s", &string1, &string2))

return NULL;

newstring = strcat(string1, string2);

return Py_BuildValue("s", newstring);

}

static PyObject* my_set_callback(PyObject *self, PyObject *args)

{

PyObject *result = NULL;

PyObject *temp;

if (PyArg_ParseTuple(args, "O", &temp))

{

if (!PyCallable_Check(temp))

{

PyErr_SetString(PyExc_TypeError, "parameter must be callable");

return NULL;

}

Py_XINCREF(temp);

Py_XDECREF(my_callback);

my_callback = temp;

Py_INCREF(Py_None);

result = Py_None;

}

return result;

}

static PyObject* my_test_callback(PyObject *self, PyObject *args)

{

PyObject * arglist;

PyObject * result = NULL;

result = PyEval_CallObject(my_callback, args);

if (result == NULL)

{

return NULL;

}

Py_DECREF(result);

Py_INCREF(Py_None);

return Py_None;

}

static PyMethodDef mytestMethods[] =

{

{"mystrlen", my_strlen, METH_VARARGS, "We test strlen of C"},

{"mystrcat", my_strcat, METH_VARARGS, "We test strcat of C"},

{"mysetcallback", my_set_callback, METH_VARARGS, "we set a call back function so that call it in C"},

{"mytestcallback", my_test_callback, METH_VARARGS, "we use this function to test call back function"},

{NULL, NULL, 0, NULL}

};

void initmytest()

{

(void) Py_InitModule("mytest", mytestMethods);

}

2 编译

gcc -fpic -c -I /usr/include/python2.6/ -I /usr/lib/python2.6/config mytest.c

gcc -shared -o mytest.so mytest.o

3 功能演示截图

4 主要参考

4.1 . Calling Python Functions from C

4.2 在windows上扩展python
http://blog.chinaunix.net/space.php?uid=46552&do=blog&id=2116527
4.3 [精华] 在windows上扩展python(2)--从c中调用python函数
http://www.linuxforum.net/forum/gshowthreaded.php?Cat=&Board=python&Number=485550&page=3&view=collapsed&sb=5&o=all&vc=1