1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/* Socket module header file */
/* Includes needed for the sockaddr_* symbols below */
#ifndef MS_WINDOWS
# include <sys/socket.h>
# include <netinet/in.h>
# if !(defined(__BEOS__) || defined(__CYGWIN__) || (defined(PYOS_OS2) && defined(PYCC_VACPP)))
# include <netinet/tcp.h>
# endif
#else /* MS_WINDOWS */
#if _MSC_VER >= 1300
# include <winsock2.h>
# include <ws2tcpip.h>
# define HAVE_ADDRINFO
# define HAVE_SOCKADDR_STORAGE
# define HAVE_GETADDRINFO
# define HAVE_GETNAMEINFO
# define ENABLE_IPV6
#else
# include <winsock.h>
#endif
#endif
#ifdef HAVE_SYS_UN_H
# include <sys/un.h>
#else
# undef AF_UNIX
#endif
#ifdef HAVE_NETPACKET_PACKET_H
# include <sys/ioctl.h>
# include <net/if.h>
# include <netpacket/packet.h>
#endif
#ifndef Py__SOCKET_H
#define Py__SOCKET_H
#ifdef __cplusplus
extern "C" {
#endif
/* Python module and C API name */
#define PySocket_MODULE_NAME "_socket"
#define PySocket_CAPI_NAME "CAPI"
/* Abstract the socket file descriptor type */
#ifdef MS_WINDOWS
typedef SOCKET SOCKET_T;
# ifdef MS_WIN64
# define SIZEOF_SOCKET_T 8
# else
# define SIZEOF_SOCKET_T 4
# endif
#else
typedef int SOCKET_T;
# define SIZEOF_SOCKET_T SIZEOF_INT
#endif
/* The object holding a socket. It holds some extra information,
like the address family, which is used to decode socket address
arguments properly. */
typedef struct {
PyObject_HEAD
SOCKET_T sock_fd; /* Socket file descriptor */
int sock_family; /* Address family, e.g., AF_INET */
int sock_type; /* Socket type, e.g., SOCK_STREAM */
int sock_proto; /* Protocol type, usually 0 */
union sock_addr {
struct sockaddr_in in;
#ifdef AF_UNIX
struct sockaddr_un un;
#endif
#ifdef ENABLE_IPV6
struct sockaddr_in6 in6;
struct sockaddr_storage storage;
#endif
#ifdef HAVE_NETPACKET_PACKET_H
struct sockaddr_ll ll;
#endif
} sock_addr;
PyObject *(*errorhandler)(void); /* Error handler; checks
errno, returns NULL and
sets a Python exception */
int sock_blocking; /* Flag indicated whether the
socket is in blocking mode */
double sock_timeout; /* Operation timeout value */
} PySocketSockObject;
/* --- C API ----------------------------------------------------*/
/* Short explanation of what this C API export mechanism does
and how it works:
The _ssl module needs access to the type object defined in
the _socket module. Since cross-DLL linking introduces a lot of
problems on many platforms, the "trick" is to wrap the
C API of a module in a struct which then gets exported to
other modules via a PyCObject.
The code in socketmodule.c defines this struct (which currently
only contains the type object reference, but could very
well also include other C APIs needed by other modules)
and exports it as PyCObject via the module dictionary
under the name "CAPI".
Other modules can now include the socketmodule.h file
which defines the needed C APIs to import and set up
a static copy of this struct in the importing module.
After initialization, the importing module can then
access the C APIs from the _socket module by simply
referring to the static struct, e.g.
Load _socket module and its C API; this sets up the global
PySocketModule:
if (PySocketModule_ImportModuleAndAPI())
return;
Now use the C API as if it were defined in the using
module:
if (!PyArg_ParseTuple(args, "O!|zz:ssl",
PySocketModule.Sock_Type,
(PyObject*)&Sock,
&key_file, &cert_file))
return NULL;
Support could easily be extended to export more C APIs/symbols
this way. Currently, only the type object is exported,
other candidates would be socket constructors and socket
access functions.
*/
/* C API for usage by other Python modules */
typedef struct {
PyTypeObject *Sock_Type;
} PySocketModule_APIObject;
/* XXX The net effect of the following appears to be to define a function
XXX named PySocketModule_APIObject in _ssl.c. It's unclear why it isn't
XXX defined there directly.
>>> It's defined here because other modules might also want to use
>>> the C API.
*/
#ifndef PySocket_BUILDING_SOCKET
/* --- C API ----------------------------------------------------*/
/* Interfacestructure to C API for other modules.
Call PySocketModule_ImportModuleAndAPI() to initialize this
structure. After that usage is simple:
if (!PyArg_ParseTuple(args, "O!|zz:ssl",
&PySocketModule.Sock_Type, (PyObject*)&Sock,
&key_file, &cert_file))
return NULL;
...
*/
static
PySocketModule_APIObject PySocketModule;
/* You *must* call this before using any of the functions in
PySocketModule and check its outcome; otherwise all accesses will
result in a segfault. Returns 0 on success. */
#ifndef DPRINTF
# define DPRINTF if (0) printf
#endif
static
int PySocketModule_ImportModuleAndAPI(void)
{
PyObject *mod = 0, *v = 0;
char *apimodule = PySocket_MODULE_NAME;
char *apiname = PySocket_CAPI_NAME;
void *api;
DPRINTF("Importing the %s C API...\n", apimodule);
mod = PyImport_ImportModule(apimodule);
if (mod == NULL)
goto onError;
DPRINTF(" %s package found\n", apimodule);
v = PyObject_GetAttrString(mod, apiname);
if (v == NULL)
goto onError;
Py_DECREF(mod);
DPRINTF(" API object %s found\n", apiname);
api = PyCObject_AsVoidPtr(v);
if (api == NULL)
goto onError;
Py_DECREF(v);
memcpy(&PySocketModule, api, sizeof(PySocketModule));
DPRINTF(" API object loaded and initialized.\n");
return 0;
onError:
DPRINTF(" not found.\n");
Py_XDECREF(mod);
Py_XDECREF(v);
return -1;
}
#endif /* !PySocket_BUILDING_SOCKET */
#ifdef __cplusplus
}
#endif
#endif /* !Py__SOCKET_H */
|
