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/* 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 PySocket_ImportModuleAPI() 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 */
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