我一直在寻找 python 的开源代码，其中许多在 src 中都有一个目录，其中包含 .c 和 .h 文件。
例如，有一个名为 protocol 的目录，其中包含 .c 和 .h 文件(这些 .c 文件具有静态 PyObject *)。
如果我想导入这个目录以便我可以使用这些函数，需要什么(或者我如何使用 .py 文件中的这些 .c 文件)？
我知道您需要 init.py 来导入目录，所以我这样做是为了导入，但不确定如何从 .c 文件访问对象
比如他们有一段python代码
arp = protocol.arp(shw, thw, sp, tp, constants.arp.ARPOP_REQUEST)
但我不理解从 .py 到 .c 的转换，因为以下文件 (protocol/arp.c) 没有名为 arp 的类(它有静态 PyObject * ARPObject_new(PyTypeObject *类型，PyObject *args，PyObject *kwds)。有人可以向我解释这种转变吗？
#include "Python.h"
#include "structmember.h"
#define PROTOCOL_MODULE
#include "protocolmodule.h"
PyProtocol_newARPObjectFromPacket_RETURN PyProtocol_newARPObjectFromPacket PyProtocol_newARPObjectFromPacket_PROTO;
PyProtocol_injectARP_RETURN PyProtocol_injectARP PyProtocol_injectARP_PROTO;
PyProtocol_ARPCheck_RETURN PyProtocol_ARPCheck PyProtocol_ARPCheck_PROTO;
int PyProtocol_ARPCheck(PyObject *o)
{
return ARPObject_Check(o);
}
/**************
* ARP *
**************/
ARPObject *
PyProtocol_newARPObjectFromPacket(arp_t *arp, int *parsed_length)
{
ARPObject *self;
char *packet = (char *) (arp + 1);
struct in_addr ia;
self = PyObject_New(ARPObject, &ARP_Type);
if (self == NULL)
return NULL;
self->ar_hrd = ntohs(arp->ar_hrd);
self->ar_pro = ntohs(arp->ar_pro);
self->ar_hln = arp->ar_hln;
self->ar_pln = arp->ar_pln;
self->ar_op = ntohs(arp->ar_op);
self->ar_spa = NULL;
self->ar_tpa = NULL;
self->ar_sha = NULL;
self->ar_tha = NULL;
self->data = NULL;
if (self->ar_pro == ETHERTYPE_IP)
{
memcpy(&ia, packet + self->ar_hln, sizeof(ia));
self->ar_spa = PyString_FromString(inet_ntoa(ia));
memcpy(&ia, packet + (2 * self->ar_hln) + self->ar_pln, sizeof(ia));
self->ar_tpa = PyString_FromString(inet_ntoa(ia));
}
else
{
PyErr_SetString(PyExc_NotImplementedError, "Only support decoding IPv4 ARP packets");
return NULL;
}
if (self->ar_hrd == ARPHRD_ETHER)
{
self->ar_sha = MACasString(packet);
self->ar_tha = MACasString(packet + self->ar_hln + self->ar_pln);
}
else
{
Py_XDECREF(self->ar_spa);
Py_XDECREF(self->ar_tpa);
PyErr_SetString(PyExc_NotImplementedError, "Only support decoding Ethernet ARP packets");
return NULL;
}
self->data = PyString_FromStringAndSize((char *) arp, (sizeof(arp_t) + (2 * self->ar_hln) + (2 * self->ar_pln)));
*parsed_length += (sizeof(arp_t) + (2 * self->ar_hln) + (2 * self->ar_pln));
return self;
}
static PyObject *
ARPObject_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
static char *kwargs[] = {"sourcehardware", "targethardware",
"sourceprotocol", "targetprotocol",
"operation", NULL };
PyObject *sourcehardware, *targethardware;
PyObject *sourceprotocol, *targetprotocol;
int operation;
ARPObject *self;
char *temp;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "SSSSi", kwargs, &sourcehardware, &targethardware,
&sourceprotocol, &targetprotocol, &operation))
return NULL;
self = PyObject_New(ARPObject, &ARP_Type);
if (! self)
return NULL;
temp = decodeMAC(sourcehardware);
if (! temp)
{
PyErr_SetString(PyExc_TypeError, "Invalid format for source MAC address");
return NULL;
}
else
free(temp);
temp = decodeMAC(targethardware);
if (! temp)
{
PyErr_SetString(PyExc_TypeError, "Invalid format for destination MAC address");
return NULL;
}
else
free(temp);
self->ar_hrd = ARPHRD_ETHER;
self->ar_pro = ETHERTYPE_IP;
self->ar_hln = ETHER_ADDR_LEN;
self->ar_pln = 4;
self->ar_op = operation;
self->data = NULL;
Py_INCREF(sourcehardware);
Py_INCREF(targethardware);
Py_INCREF(sourceprotocol);
Py_INCREF(targetprotocol);
self->ar_sha = sourcehardware;
self->ar_tha = targethardware;
self->ar_spa = sourceprotocol;
self->ar_tpa = targetprotocol;
return (PyObject *) self;
}
int
PyProtocol_injectARP(PyObject *arp_py, libnet_t *context)
{
ARPObject *self = (ARPObject *) arp_py;
char *sha = decodeMAC(self->ar_sha);
char *tha = decodeMAC(self->ar_tha);
struct in_addr spa, tpa;
libnet_ptag_t r;
inet_aton(PyString_AsString(self->ar_spa), &spa);
inet_aton(PyString_AsString(self->ar_tpa), &tpa);
r = libnet_build_arp(self->ar_hrd,
self->ar_pro,
self->ar_hln,
self->ar_pln,
self->ar_op,
sha, // Source hardware address
(char *) &spa, // Target hardware address
tha, // Source protocol address
(char *) &tpa, // Target protocol address
NULL,
0,
context,
0);
free(sha);
free(tha);
if (r == -1)
{
PyErr_SetString(ErrorObject, libnet_geterror(context));
return 0;
}
return 1;
}
static void
ARPObject_dealloc(ARPObject *self)
{
Py_XDECREF(self->ar_sha);
Py_XDECREF(self->ar_tha);
Py_XDECREF(self->ar_spa);
Py_XDECREF(self->ar_tpa);
Py_XDECREF(self->data);
PyObject_Del(self);
}
static PyObject *
ARPObject_str(ARPObject * self)
{
PyObject *result = PyString_FromFormat("ARP(op=0x%04x, protocol=0x%04x, %s (%s) -> %s (%s))",
self->ar_op, self->ar_pro,
PyString_AsString(self->ar_sha),
PyString_AsString(self->ar_spa),
PyString_AsString(self->ar_tha),
PyString_AsString(self->ar_tpa));
return result;
}
static PyMethodDef ARPObject_methods[] =
{
{NULL, NULL}
};
static PyMemberDef ARPObject_members[] =
{
{"protocol", T_USHORT, offsetof(ARPObject, ar_pro), 0, "ARP requested protocol"},
{"operation", T_USHORT, offsetof(ARPObject, ar_op), 0, "ARP operation"},
{"hardwarelength", T_USHORT, offsetof(ARPObject, ar_hln), 0, "ARP hardware address length"},
{"protocollength", T_USHORT, offsetof(ARPObject, ar_pln), 0, "ARP protocol address length"},
{"hardwareformat", T_USHORT, offsetof(ARPObject, ar_hrd), 0, "ARP hardware type"},
{"sourcehardware", T_OBJECT, offsetof(ARPObject, ar_sha), 0, "ARP source hardware address"},
{"targethardware", T_OBJECT, offsetof(ARPObject, ar_tha), 0, "ARP target hardware address"},
{"sourceprotocol", T_OBJECT, offsetof(ARPObject, ar_spa), 0, "ARP source protocol address"},
{"targetprotocol", T_OBJECT, offsetof(ARPObject, ar_tpa), 0, "ARP target protocol address"},
{"packet", T_OBJECT, offsetof(ARPObject, data), READONLY, "Raw packet data"},
{ NULL }
};
PyTypeObject ARP_Type =
{
/* The ob_type field must be initialized in the module init function
* to be portable to Windows without using C++. */
PyObject_HEAD_INIT(NULL)
0, /*ob_size*/
"pycap.protocol.arp", /*tp_name*/
sizeof(ARPObject), /*tp_basicsize*/
0, /*tp_itemsize*/
/* methods */
(destructor)ARPObject_dealloc, /*tp_dealloc*/
0, /*tp_print*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_compare*/
(reprfunc)ARPObject_str, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /*tp_hash*/
0, /*tp_call*/
(reprfunc)ARPObject_str, /*tp_str*/
0, /*tp_getattro*/
0, /*tp_setattro*/
0, /*tp_as_buffer*/
Py_TPFLAGS_DEFAULT, /*tp_flags*/
"ARP packet", /*tp_doc*/
0, /*tp_traverse*/
0, /*tp_clear*/
0, /*tp_richcompare*/
0, /*tp_weaklistoffset*/
0, /*tp_iter*/
0, /*tp_iternext*/
ARPObject_methods, /*tp_methods*/
ARPObject_members, /*tp_members*/
0, /*tp_getset*/
0, /*tp_base*/
0, /*tp_dict*/
0, /*tp_descr_get*/
0, /*tp_descr_set*/
0, /*tp_dictoffset*/
0, /*tp_init*/
0, /*tp_alloc*/
ARPObject_new, /*tp_new*/
0, /*tp_free*/
0, /*tp_is_gc*/
};
int initARPType(PyObject *module_dict)
{
if (PyType_Ready(&ARP_Type) < 0)
return 1;
PyDict_SetItemString(module_dict, "arp", (PyObject *) &ARP_Type);
return 0;
}
最佳答案
这些模块有 .c 元素来加速处理，(即它们不是纯 python)，因此需要根据平台区别对待。
在非windows系统上
你需要运行:
python setup.py build
python setup.py install
在非 Windows 系统上。
MS-Windows 系统
在 Windows 系统上，您将必须安装所有适当的工具，然后执行与非 Windows 系统相同的操作，或者找到并安装一个 Windows 版本以匹配您的 Python 版本。
请注意在 Pypi 指向的官方构建之后，Python 工具的 Windows 构建最有用的页面之一。由 Christoph Gohlke 在他的 Unofficial Windows Binaries for Python Extension Packages 中提供所以如果你没有找到基于 PyPi 的 Windows ，或项目主页，然后在那里尝试。
两者
无论哪种方式，适当的二进制文件都将在 .egg 文件中，您只需导入模块并使用函数即可。
提示
尝试几乎所有 python 库的几个技巧: 在 python 终端中，(为拉伸(stretch)示例道歉):
import parrot # Or whatever your library is called
dir(parrot) # This will give you a list of methods and members of parrot
dir(parrot.Norwegian) # Assuming that parrot has a member by that name
help(parrot) # Will give top level help followed by help on the members
help(parrot.Norwegian) # Should tell you that it has a member Blue that doesn't do a lot
发布代码的快速解释
为了澄清问题中发布的代码 - 一旦您执行了上述步骤并导入了包，它将向名为 arp 的命名空间添加一个新的类类型 - 这是由 PyDict_SetItemString(module_dict, "arp", (PyObject *) &ARP_Type); 以及 ARPObject_members 和 ARPObject_methods 中定义的成员和方法，希望记录在模块文档。
关于带有 C 库的 Python，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21227992/