/Modules/_multiprocessing/multiprocessing.c
http://unladen-swallow.googlecode.com/ · C · 311 lines · 224 code · 49 blank · 38 comment · 27 complexity · 98d5e4f8bff6ec15f349c9ae31dfca89 MD5 · raw file
- /*
- * Extension module used by multiprocessing package
- *
- * multiprocessing.c
- *
- * Copyright (c) 2006-2008, R Oudkerk --- see COPYING.txt
- */
- #include "multiprocessing.h"
- PyObject *create_win32_namespace(void);
- PyObject *pickle_dumps, *pickle_loads, *pickle_protocol;
- PyObject *ProcessError, *BufferTooShort;
- /*
- * Function which raises exceptions based on error codes
- */
- PyObject *
- mp_SetError(PyObject *Type, int num)
- {
- switch (num) {
- #ifdef MS_WINDOWS
- case MP_STANDARD_ERROR:
- if (Type == NULL)
- Type = PyExc_WindowsError;
- PyErr_SetExcFromWindowsErr(Type, 0);
- break;
- case MP_SOCKET_ERROR:
- if (Type == NULL)
- Type = PyExc_WindowsError;
- PyErr_SetExcFromWindowsErr(Type, WSAGetLastError());
- break;
- #else /* !MS_WINDOWS */
- case MP_STANDARD_ERROR:
- case MP_SOCKET_ERROR:
- if (Type == NULL)
- Type = PyExc_OSError;
- PyErr_SetFromErrno(Type);
- break;
- #endif /* !MS_WINDOWS */
- case MP_MEMORY_ERROR:
- PyErr_NoMemory();
- break;
- case MP_END_OF_FILE:
- PyErr_SetNone(PyExc_EOFError);
- break;
- case MP_EARLY_END_OF_FILE:
- PyErr_SetString(PyExc_IOError,
- "got end of file during message");
- break;
- case MP_BAD_MESSAGE_LENGTH:
- PyErr_SetString(PyExc_IOError, "bad message length");
- break;
- case MP_EXCEPTION_HAS_BEEN_SET:
- break;
- default:
- PyErr_Format(PyExc_RuntimeError,
- "unkown error number %d", num);
- }
- return NULL;
- }
- /*
- * Windows only
- */
- #ifdef MS_WINDOWS
- /* On Windows we set an event to signal Ctrl-C; compare with timemodule.c */
- HANDLE sigint_event = NULL;
- static BOOL WINAPI
- ProcessingCtrlHandler(DWORD dwCtrlType)
- {
- SetEvent(sigint_event);
- return FALSE;
- }
- /*
- * Unix only
- */
- #else /* !MS_WINDOWS */
- #if HAVE_FD_TRANSFER
- /* Functions for transferring file descriptors between processes.
- Reimplements some of the functionality of the fdcred
- module at http://www.mca-ltd.com/resources/fdcred_1.tgz. */
- static PyObject *
- multiprocessing_sendfd(PyObject *self, PyObject *args)
- {
- int conn, fd, res;
- char dummy_char;
- char buf[CMSG_SPACE(sizeof(int))];
- struct msghdr msg = {0};
- struct iovec dummy_iov;
- struct cmsghdr *cmsg;
- if (!PyArg_ParseTuple(args, "ii", &conn, &fd))
- return NULL;
- dummy_iov.iov_base = &dummy_char;
- dummy_iov.iov_len = 1;
- msg.msg_control = buf;
- msg.msg_controllen = sizeof(buf);
- msg.msg_iov = &dummy_iov;
- msg.msg_iovlen = 1;
- cmsg = CMSG_FIRSTHDR(&msg);
- cmsg->cmsg_level = SOL_SOCKET;
- cmsg->cmsg_type = SCM_RIGHTS;
- cmsg->cmsg_len = CMSG_LEN(sizeof(int));
- msg.msg_controllen = cmsg->cmsg_len;
- *(int*)CMSG_DATA(cmsg) = fd;
- Py_BEGIN_ALLOW_THREADS
- res = sendmsg(conn, &msg, 0);
- Py_END_ALLOW_THREADS
- if (res < 0)
- return PyErr_SetFromErrno(PyExc_OSError);
- Py_RETURN_NONE;
- }
- static PyObject *
- multiprocessing_recvfd(PyObject *self, PyObject *args)
- {
- int conn, fd, res;
- char dummy_char;
- char buf[CMSG_SPACE(sizeof(int))];
- struct msghdr msg = {0};
- struct iovec dummy_iov;
- struct cmsghdr *cmsg;
- if (!PyArg_ParseTuple(args, "i", &conn))
- return NULL;
- dummy_iov.iov_base = &dummy_char;
- dummy_iov.iov_len = 1;
- msg.msg_control = buf;
- msg.msg_controllen = sizeof(buf);
- msg.msg_iov = &dummy_iov;
- msg.msg_iovlen = 1;
- cmsg = CMSG_FIRSTHDR(&msg);
- cmsg->cmsg_level = SOL_SOCKET;
- cmsg->cmsg_type = SCM_RIGHTS;
- cmsg->cmsg_len = CMSG_LEN(sizeof(int));
- msg.msg_controllen = cmsg->cmsg_len;
- Py_BEGIN_ALLOW_THREADS
- res = recvmsg(conn, &msg, 0);
- Py_END_ALLOW_THREADS
- if (res < 0)
- return PyErr_SetFromErrno(PyExc_OSError);
- fd = *(int*)CMSG_DATA(cmsg);
- return Py_BuildValue("i", fd);
- }
- #endif /* HAVE_FD_TRANSFER */
- #endif /* !MS_WINDOWS */
- /*
- * All platforms
- */
- static PyObject*
- multiprocessing_address_of_buffer(PyObject *self, PyObject *obj)
- {
- void *buffer;
- Py_ssize_t buffer_len;
- if (PyObject_AsWriteBuffer(obj, &buffer, &buffer_len) < 0)
- return NULL;
- return Py_BuildValue("N" F_PY_SSIZE_T,
- PyLong_FromVoidPtr(buffer), buffer_len);
- }
- /*
- * Function table
- */
- static PyMethodDef module_methods[] = {
- {"address_of_buffer", multiprocessing_address_of_buffer, METH_O,
- "address_of_buffer(obj) -> int\n"
- "Return address of obj assuming obj supports buffer inteface"},
- #if HAVE_FD_TRANSFER
- {"sendfd", multiprocessing_sendfd, METH_VARARGS,
- "sendfd(sockfd, fd) -> None\n"
- "Send file descriptor given by fd over the unix domain socket\n"
- "whose file decriptor is sockfd"},
- {"recvfd", multiprocessing_recvfd, METH_VARARGS,
- "recvfd(sockfd) -> fd\n"
- "Receive a file descriptor over a unix domain socket\n"
- "whose file decriptor is sockfd"},
- #endif
- {NULL}
- };
- /*
- * Initialize
- */
- PyMODINIT_FUNC
- init_multiprocessing(void)
- {
- PyObject *module, *temp, *value;
- /* Initialize module */
- module = Py_InitModule("_multiprocessing", module_methods);
- if (!module)
- return;
- /* Get copy of objects from pickle */
- temp = PyImport_ImportModule(PICKLE_MODULE);
- if (!temp)
- return;
- pickle_dumps = PyObject_GetAttrString(temp, "dumps");
- pickle_loads = PyObject_GetAttrString(temp, "loads");
- pickle_protocol = PyObject_GetAttrString(temp, "HIGHEST_PROTOCOL");
- Py_XDECREF(temp);
- /* Get copy of BufferTooShort */
- temp = PyImport_ImportModule("multiprocessing");
- if (!temp)
- return;
- BufferTooShort = PyObject_GetAttrString(temp, "BufferTooShort");
- Py_XDECREF(temp);
- /* Add connection type to module */
- if (PyType_Ready(&ConnectionType) < 0)
- return;
- Py_INCREF(&ConnectionType);
- PyModule_AddObject(module, "Connection", (PyObject*)&ConnectionType);
- #if defined(MS_WINDOWS) || HAVE_SEM_OPEN
- /* Add SemLock type to module */
- if (PyType_Ready(&SemLockType) < 0)
- return;
- Py_INCREF(&SemLockType);
- PyDict_SetItemString(SemLockType.tp_dict, "SEM_VALUE_MAX",
- Py_BuildValue("i", SEM_VALUE_MAX));
- PyModule_AddObject(module, "SemLock", (PyObject*)&SemLockType);
- #endif
- #ifdef MS_WINDOWS
- /* Add PipeConnection to module */
- if (PyType_Ready(&PipeConnectionType) < 0)
- return;
- Py_INCREF(&PipeConnectionType);
- PyModule_AddObject(module, "PipeConnection",
- (PyObject*)&PipeConnectionType);
- /* Initialize win32 class and add to multiprocessing */
- temp = create_win32_namespace();
- if (!temp)
- return;
- PyModule_AddObject(module, "win32", temp);
- /* Initialize the event handle used to signal Ctrl-C */
- sigint_event = CreateEvent(NULL, TRUE, FALSE, NULL);
- if (!sigint_event) {
- PyErr_SetFromWindowsErr(0);
- return;
- }
- if (!SetConsoleCtrlHandler(ProcessingCtrlHandler, TRUE)) {
- PyErr_SetFromWindowsErr(0);
- return;
- }
- #endif
- /* Add configuration macros */
- temp = PyDict_New();
- if (!temp)
- return;
- #define ADD_FLAG(name) \
- value = Py_BuildValue("i", name); \
- if (value == NULL) { Py_DECREF(temp); return; } \
- if (PyDict_SetItemString(temp, #name, value) < 0) { \
- Py_DECREF(temp); Py_DECREF(value); return; } \
- Py_DECREF(value)
-
- #ifdef HAVE_SEM_OPEN
- ADD_FLAG(HAVE_SEM_OPEN);
- #endif
- #ifdef HAVE_SEM_TIMEDWAIT
- ADD_FLAG(HAVE_SEM_TIMEDWAIT);
- #endif
- #ifdef HAVE_FD_TRANSFER
- ADD_FLAG(HAVE_FD_TRANSFER);
- #endif
- #ifdef HAVE_BROKEN_SEM_GETVALUE
- ADD_FLAG(HAVE_BROKEN_SEM_GETVALUE);
- #endif
- #ifdef HAVE_BROKEN_SEM_UNLINK
- ADD_FLAG(HAVE_BROKEN_SEM_UNLINK);
- #endif
- if (PyModule_AddObject(module, "flags", temp) < 0)
- return;
- }