| /* select - Module containing unix select(2) call. |
| Under Unix, the file descriptors are small integers. |
| Under Win32, select only exists for sockets, and sockets may |
| have any value except INVALID_SOCKET. |
| Under BeOS, we suffer the same dichotomy as Win32; sockets can be anything |
| >= 0. |
| */ |
| |
| #include "Python.h" |
| |
| /* Windows #defines FD_SETSIZE to 64 if FD_SETSIZE isn't already defined. |
| 64 is too small (too many people have bumped into that limit). |
| Here we boost it. |
| Users who want even more than the boosted limit should #define |
| FD_SETSIZE higher before this; e.g., via compiler /D switch. |
| */ |
| #if defined(MS_WINDOWS) && !defined(FD_SETSIZE) |
| #define FD_SETSIZE 512 |
| #endif |
| |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #if defined(HAVE_POLL_H) |
| #include <poll.h> |
| #elif defined(HAVE_SYS_POLL_H) |
| #include <sys/poll.h> |
| #endif |
| |
| #ifdef __sgi |
| /* This is missing from unistd.h */ |
| extern void bzero(void *, int); |
| #endif |
| |
| #ifndef DONT_HAVE_SYS_TYPES_H |
| #include <sys/types.h> |
| #endif |
| |
| #if defined(PYOS_OS2) |
| #include <sys/time.h> |
| #include <utils.h> |
| #endif |
| |
| #ifdef MS_WINDOWS |
| #include <winsock.h> |
| #else |
| #ifdef __BEOS__ |
| #include <net/socket.h> |
| #define SOCKET int |
| #else |
| #define SOCKET int |
| #endif |
| #endif |
| |
| #ifdef RISCOS |
| #define NO_DUP |
| #undef off_t |
| #undef uid_t |
| #undef gid_t |
| #undef errno |
| #include "socklib.h" |
| #endif /* RISCOS */ |
| |
| static PyObject *SelectError; |
| |
| /* list of Python objects and their file descriptor */ |
| typedef struct { |
| PyObject *obj; /* owned reference */ |
| SOCKET fd; |
| int sentinel; /* -1 == sentinel */ |
| } pylist; |
| |
| static void |
| reap_obj(pylist fd2obj[FD_SETSIZE + 1]) |
| { |
| int i; |
| for (i = 0; i < FD_SETSIZE + 1 && fd2obj[i].sentinel >= 0; i++) { |
| Py_XDECREF(fd2obj[i].obj); |
| fd2obj[i].obj = NULL; |
| } |
| fd2obj[0].sentinel = -1; |
| } |
| |
| |
| /* returns -1 and sets the Python exception if an error occurred, otherwise |
| returns a number >= 0 |
| */ |
| static int |
| list2set(PyObject *list, fd_set *set, pylist fd2obj[FD_SETSIZE + 1]) |
| { |
| int i; |
| int max = -1; |
| int index = 0; |
| int len = PyList_Size(list); |
| PyObject* o = NULL; |
| |
| fd2obj[0].obj = (PyObject*)0; /* set list to zero size */ |
| FD_ZERO(set); |
| |
| for (i = 0; i < len; i++) { |
| SOCKET v; |
| |
| /* any intervening fileno() calls could decr this refcnt */ |
| if (!(o = PyList_GetItem(list, i))) |
| return -1; |
| |
| Py_INCREF(o); |
| v = PyObject_AsFileDescriptor( o ); |
| if (v == -1) goto finally; |
| |
| #if defined(_MSC_VER) |
| max = 0; /* not used for Win32 */ |
| #else /* !_MSC_VER */ |
| if (v < 0 || v >= FD_SETSIZE) { |
| PyErr_SetString(PyExc_ValueError, |
| "filedescriptor out of range in select()"); |
| goto finally; |
| } |
| if (v > max) |
| max = v; |
| #endif /* _MSC_VER */ |
| FD_SET(v, set); |
| |
| /* add object and its file descriptor to the list */ |
| if (index >= FD_SETSIZE) { |
| PyErr_SetString(PyExc_ValueError, |
| "too many file descriptors in select()"); |
| goto finally; |
| } |
| fd2obj[index].obj = o; |
| fd2obj[index].fd = v; |
| fd2obj[index].sentinel = 0; |
| fd2obj[++index].sentinel = -1; |
| } |
| return max+1; |
| |
| finally: |
| Py_XDECREF(o); |
| return -1; |
| } |
| |
| /* returns NULL and sets the Python exception if an error occurred */ |
| static PyObject * |
| set2list(fd_set *set, pylist fd2obj[FD_SETSIZE + 1]) |
| { |
| int i, j, count=0; |
| PyObject *list, *o; |
| SOCKET fd; |
| |
| for (j = 0; fd2obj[j].sentinel >= 0; j++) { |
| if (FD_ISSET(fd2obj[j].fd, set)) |
| count++; |
| } |
| list = PyList_New(count); |
| if (!list) |
| return NULL; |
| |
| i = 0; |
| for (j = 0; fd2obj[j].sentinel >= 0; j++) { |
| fd = fd2obj[j].fd; |
| if (FD_ISSET(fd, set)) { |
| #ifndef _MSC_VER |
| if (fd > FD_SETSIZE) { |
| PyErr_SetString(PyExc_SystemError, |
| "filedescriptor out of range returned in select()"); |
| goto finally; |
| } |
| #endif |
| o = fd2obj[j].obj; |
| fd2obj[j].obj = NULL; |
| /* transfer ownership */ |
| if (PyList_SetItem(list, i, o) < 0) |
| goto finally; |
| |
| i++; |
| } |
| } |
| return list; |
| finally: |
| Py_DECREF(list); |
| return NULL; |
| } |
| |
| #undef SELECT_USES_HEAP |
| #if FD_SETSIZE > 1024 |
| #define SELECT_USES_HEAP |
| #endif /* FD_SETSIZE > 1024 */ |
| |
| static PyObject * |
| select_select(PyObject *self, PyObject *args) |
| { |
| #ifdef SELECT_USES_HEAP |
| pylist *rfd2obj, *wfd2obj, *efd2obj; |
| #else /* !SELECT_USES_HEAP */ |
| /* XXX: All this should probably be implemented as follows: |
| * - find the highest descriptor we're interested in |
| * - add one |
| * - that's the size |
| * See: Stevens, APitUE, $12.5.1 |
| */ |
| pylist rfd2obj[FD_SETSIZE + 1]; |
| pylist wfd2obj[FD_SETSIZE + 1]; |
| pylist efd2obj[FD_SETSIZE + 1]; |
| #endif /* SELECT_USES_HEAP */ |
| PyObject *ifdlist, *ofdlist, *efdlist; |
| PyObject *ret = NULL; |
| PyObject *tout = Py_None; |
| fd_set ifdset, ofdset, efdset; |
| double timeout; |
| struct timeval tv, *tvp; |
| long seconds; |
| int imax, omax, emax, max; |
| int n; |
| |
| /* convert arguments */ |
| if (!PyArg_ParseTuple(args, "OOO|O:select", |
| &ifdlist, &ofdlist, &efdlist, &tout)) |
| return NULL; |
| |
| if (tout == Py_None) |
| tvp = (struct timeval *)0; |
| else if (!PyArg_Parse(tout, "d", &timeout)) { |
| PyErr_SetString(PyExc_TypeError, |
| "timeout must be a float or None"); |
| return NULL; |
| } |
| else { |
| if (timeout > (double)LONG_MAX) { |
| PyErr_SetString(PyExc_OverflowError, |
| "timeout period too long"); |
| return NULL; |
| } |
| seconds = (long)timeout; |
| timeout = timeout - (double)seconds; |
| tv.tv_sec = seconds; |
| tv.tv_usec = (long)(timeout*1000000.0); |
| tvp = &tv; |
| } |
| |
| /* sanity check first three arguments */ |
| if (!PyList_Check(ifdlist) || |
| !PyList_Check(ofdlist) || |
| !PyList_Check(efdlist)) |
| { |
| PyErr_SetString(PyExc_TypeError, |
| "arguments 1-3 must be lists"); |
| return NULL; |
| } |
| |
| #ifdef SELECT_USES_HEAP |
| /* Allocate memory for the lists */ |
| rfd2obj = PyMem_NEW(pylist, FD_SETSIZE + 1); |
| wfd2obj = PyMem_NEW(pylist, FD_SETSIZE + 1); |
| efd2obj = PyMem_NEW(pylist, FD_SETSIZE + 1); |
| if (rfd2obj == NULL || wfd2obj == NULL || efd2obj == NULL) { |
| if (rfd2obj) PyMem_DEL(rfd2obj); |
| if (wfd2obj) PyMem_DEL(wfd2obj); |
| if (efd2obj) PyMem_DEL(efd2obj); |
| return NULL; |
| } |
| #endif /* SELECT_USES_HEAP */ |
| /* Convert lists to fd_sets, and get maximum fd number |
| * propagates the Python exception set in list2set() |
| */ |
| rfd2obj[0].sentinel = -1; |
| wfd2obj[0].sentinel = -1; |
| efd2obj[0].sentinel = -1; |
| if ((imax=list2set(ifdlist, &ifdset, rfd2obj)) < 0) |
| goto finally; |
| if ((omax=list2set(ofdlist, &ofdset, wfd2obj)) < 0) |
| goto finally; |
| if ((emax=list2set(efdlist, &efdset, efd2obj)) < 0) |
| goto finally; |
| max = imax; |
| if (omax > max) max = omax; |
| if (emax > max) max = emax; |
| |
| Py_BEGIN_ALLOW_THREADS |
| n = select(max, &ifdset, &ofdset, &efdset, tvp); |
| Py_END_ALLOW_THREADS |
| |
| if (n < 0) { |
| PyErr_SetFromErrno(SelectError); |
| } |
| else if (n == 0) { |
| /* optimization */ |
| ifdlist = PyList_New(0); |
| if (ifdlist) { |
| ret = Py_BuildValue("OOO", ifdlist, ifdlist, ifdlist); |
| Py_DECREF(ifdlist); |
| } |
| } |
| else { |
| /* any of these three calls can raise an exception. it's more |
| convenient to test for this after all three calls... but |
| is that acceptable? |
| */ |
| ifdlist = set2list(&ifdset, rfd2obj); |
| ofdlist = set2list(&ofdset, wfd2obj); |
| efdlist = set2list(&efdset, efd2obj); |
| if (PyErr_Occurred()) |
| ret = NULL; |
| else |
| ret = Py_BuildValue("OOO", ifdlist, ofdlist, efdlist); |
| |
| Py_DECREF(ifdlist); |
| Py_DECREF(ofdlist); |
| Py_DECREF(efdlist); |
| } |
| |
| finally: |
| reap_obj(rfd2obj); |
| reap_obj(wfd2obj); |
| reap_obj(efd2obj); |
| #ifdef SELECT_USES_HEAP |
| PyMem_DEL(rfd2obj); |
| PyMem_DEL(wfd2obj); |
| PyMem_DEL(efd2obj); |
| #endif /* SELECT_USES_HEAP */ |
| return ret; |
| } |
| |
| #ifdef HAVE_POLL |
| /* |
| * poll() support |
| */ |
| |
| typedef struct { |
| PyObject_HEAD |
| PyObject *dict; |
| int ufd_uptodate; |
| int ufd_len; |
| struct pollfd *ufds; |
| } pollObject; |
| |
| staticforward PyTypeObject poll_Type; |
| |
| /* Update the malloc'ed array of pollfds to match the dictionary |
| contained within a pollObject. Return 1 on success, 0 on an error. |
| */ |
| |
| static int |
| update_ufd_array(pollObject *self) |
| { |
| int i, pos; |
| PyObject *key, *value; |
| |
| self->ufd_len = PyDict_Size(self->dict); |
| PyMem_Resize(self->ufds, struct pollfd, self->ufd_len); |
| if (self->ufds == NULL) { |
| PyErr_NoMemory(); |
| return 0; |
| } |
| |
| i = pos = 0; |
| while (PyDict_Next(self->dict, &pos, &key, &value)) { |
| self->ufds[i].fd = PyInt_AsLong(key); |
| self->ufds[i].events = (short)PyInt_AsLong(value); |
| i++; |
| } |
| self->ufd_uptodate = 1; |
| return 1; |
| } |
| |
| static char poll_register_doc[] = |
| "register(fd [, eventmask] ) -> None\n\n\ |
| Register a file descriptor with the polling object.\n\ |
| fd -- either an integer, or an object with a fileno() method returning an\n\ |
| int.\n\ |
| events -- an optional bitmask describing the type of events to check for"; |
| |
| static PyObject * |
| poll_register(pollObject *self, PyObject *args) |
| { |
| PyObject *o, *key, *value; |
| int fd, events = POLLIN | POLLPRI | POLLOUT; |
| |
| if (!PyArg_ParseTuple(args, "O|i:register", &o, &events)) { |
| return NULL; |
| } |
| |
| fd = PyObject_AsFileDescriptor(o); |
| if (fd == -1) return NULL; |
| |
| /* Add entry to the internal dictionary: the key is the |
| file descriptor, and the value is the event mask. */ |
| if ( (NULL == (key = PyInt_FromLong(fd))) || |
| (NULL == (value = PyInt_FromLong(events))) || |
| (PyDict_SetItem(self->dict, key, value)) == -1) { |
| return NULL; |
| } |
| self->ufd_uptodate = 0; |
| |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| |
| static char poll_unregister_doc[] = |
| "unregister(fd) -> None\n\n\ |
| Remove a file descriptor being tracked by the polling object."; |
| |
| static PyObject * |
| poll_unregister(pollObject *self, PyObject *args) |
| { |
| PyObject *o, *key; |
| int fd; |
| |
| if (!PyArg_ParseTuple(args, "O:unregister", &o)) { |
| return NULL; |
| } |
| |
| fd = PyObject_AsFileDescriptor( o ); |
| if (fd == -1) |
| return NULL; |
| |
| /* Check whether the fd is already in the array */ |
| key = PyInt_FromLong(fd); |
| if (key == NULL) |
| return NULL; |
| |
| if (PyDict_DelItem(self->dict, key) == -1) { |
| Py_DECREF(key); |
| /* This will simply raise the KeyError set by PyDict_DelItem |
| if the file descriptor isn't registered. */ |
| return NULL; |
| } |
| |
| Py_DECREF(key); |
| self->ufd_uptodate = 0; |
| |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| |
| static char poll_poll_doc[] = |
| "poll( [timeout] ) -> list of (fd, event) 2-tuples\n\n\ |
| Polls the set of registered file descriptors, returning a list containing \n\ |
| any descriptors that have events or errors to report."; |
| |
| static PyObject * |
| poll_poll(pollObject *self, PyObject *args) |
| { |
| PyObject *result_list = NULL, *tout = NULL; |
| int timeout = 0, poll_result, i, j; |
| PyObject *value = NULL, *num = NULL; |
| |
| if (!PyArg_ParseTuple(args, "|O:poll", &tout)) { |
| return NULL; |
| } |
| |
| /* Check values for timeout */ |
| if (tout == NULL || tout == Py_None) |
| timeout = -1; |
| else if (!PyArg_Parse(tout, "i", &timeout)) { |
| PyErr_SetString(PyExc_TypeError, |
| "timeout must be an integer or None"); |
| return NULL; |
| } |
| |
| /* Ensure the ufd array is up to date */ |
| if (!self->ufd_uptodate) |
| if (update_ufd_array(self) == 0) |
| return NULL; |
| |
| /* call poll() */ |
| Py_BEGIN_ALLOW_THREADS; |
| poll_result = poll(self->ufds, self->ufd_len, timeout); |
| Py_END_ALLOW_THREADS; |
| |
| if (poll_result < 0) { |
| PyErr_SetFromErrno(SelectError); |
| return NULL; |
| } |
| |
| /* build the result list */ |
| |
| result_list = PyList_New(poll_result); |
| if (!result_list) |
| return NULL; |
| else { |
| for (i = 0, j = 0; j < poll_result; j++) { |
| /* skip to the next fired descriptor */ |
| while (!self->ufds[i].revents) { |
| i++; |
| } |
| /* if we hit a NULL return, set value to NULL |
| and break out of loop; code at end will |
| clean up result_list */ |
| value = PyTuple_New(2); |
| if (value == NULL) |
| goto error; |
| num = PyInt_FromLong(self->ufds[i].fd); |
| if (num == NULL) { |
| Py_DECREF(value); |
| goto error; |
| } |
| PyTuple_SET_ITEM(value, 0, num); |
| |
| num = PyInt_FromLong(self->ufds[i].revents); |
| if (num == NULL) { |
| Py_DECREF(value); |
| goto error; |
| } |
| PyTuple_SET_ITEM(value, 1, num); |
| if ((PyList_SetItem(result_list, j, value)) == -1) { |
| Py_DECREF(value); |
| goto error; |
| } |
| i++; |
| } |
| } |
| return result_list; |
| |
| error: |
| Py_DECREF(result_list); |
| return NULL; |
| } |
| |
| static PyMethodDef poll_methods[] = { |
| {"register", (PyCFunction)poll_register, |
| METH_VARARGS, poll_register_doc}, |
| {"unregister", (PyCFunction)poll_unregister, |
| METH_VARARGS, poll_unregister_doc}, |
| {"poll", (PyCFunction)poll_poll, |
| METH_VARARGS, poll_poll_doc}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| static pollObject * |
| newPollObject(void) |
| { |
| pollObject *self; |
| self = PyObject_New(pollObject, &poll_Type); |
| if (self == NULL) |
| return NULL; |
| /* ufd_uptodate is a Boolean, denoting whether the |
| array pointed to by ufds matches the contents of the dictionary. */ |
| self->ufd_uptodate = 0; |
| self->ufds = NULL; |
| self->dict = PyDict_New(); |
| if (self->dict == NULL) { |
| Py_DECREF(self); |
| return NULL; |
| } |
| return self; |
| } |
| |
| static void |
| poll_dealloc(pollObject *self) |
| { |
| if (self->ufds != NULL) |
| PyMem_DEL(self->ufds); |
| Py_XDECREF(self->dict); |
| PyObject_Del(self); |
| } |
| |
| static PyObject * |
| poll_getattr(pollObject *self, char *name) |
| { |
| return Py_FindMethod(poll_methods, (PyObject *)self, name); |
| } |
| |
| statichere PyTypeObject poll_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*/ |
| "poll", /*tp_name*/ |
| sizeof(pollObject), /*tp_basicsize*/ |
| 0, /*tp_itemsize*/ |
| /* methods */ |
| (destructor)poll_dealloc, /*tp_dealloc*/ |
| 0, /*tp_print*/ |
| (getattrfunc)poll_getattr, /*tp_getattr*/ |
| 0, /*tp_setattr*/ |
| 0, /*tp_compare*/ |
| 0, /*tp_repr*/ |
| 0, /*tp_as_number*/ |
| 0, /*tp_as_sequence*/ |
| 0, /*tp_as_mapping*/ |
| 0, /*tp_hash*/ |
| }; |
| |
| static char poll_doc[] = |
| "Returns a polling object, which supports registering and\n\ |
| unregistering file descriptors, and then polling them for I/O events."; |
| |
| static PyObject * |
| select_poll(PyObject *self, PyObject *args) |
| { |
| pollObject *rv; |
| |
| if (!PyArg_ParseTuple(args, ":poll")) |
| return NULL; |
| rv = newPollObject(); |
| if ( rv == NULL ) |
| return NULL; |
| return (PyObject *)rv; |
| } |
| #endif /* HAVE_POLL */ |
| |
| static char select_doc[] = |
| "select(rlist, wlist, xlist[, timeout]) -> (rlist, wlist, xlist)\n\ |
| \n\ |
| Wait until one or more file descriptors are ready for some kind of I/O.\n\ |
| The first three arguments are lists of file descriptors to be waited for:\n\ |
| rlist -- wait until ready for reading\n\ |
| wlist -- wait until ready for writing\n\ |
| xlist -- wait for an ``exceptional condition''\n\ |
| If only one kind of condition is required, pass [] for the other lists.\n\ |
| A file descriptor is either a socket or file object, or a small integer\n\ |
| gotten from a fileno() method call on one of those.\n\ |
| \n\ |
| The optional 4th argument specifies a timeout in seconds; it may be\n\ |
| a floating point number to specify fractions of seconds. If it is absent\n\ |
| or None, the call will never time out.\n\ |
| \n\ |
| The return value is a tuple of three lists corresponding to the first three\n\ |
| arguments; each contains the subset of the corresponding file descriptors\n\ |
| that are ready.\n\ |
| \n\ |
| *** IMPORTANT NOTICE ***\n\ |
| On Windows, only sockets are supported; on Unix, all file descriptors."; |
| |
| static PyMethodDef select_methods[] = { |
| {"select", select_select, METH_VARARGS, select_doc}, |
| #ifdef HAVE_POLL |
| {"poll", select_poll, METH_VARARGS, poll_doc}, |
| #endif /* HAVE_POLL */ |
| {0, 0}, /* sentinel */ |
| }; |
| |
| static char module_doc[] = |
| "This module supports asynchronous I/O on multiple file descriptors.\n\ |
| \n\ |
| *** IMPORTANT NOTICE ***\n\ |
| On Windows, only sockets are supported; on Unix, all file descriptors."; |
| |
| /* |
| * Convenience routine to export an integer value. |
| * For simplicity, errors (which are unlikely anyway) are ignored. |
| */ |
| |
| static void |
| insint(PyObject *d, char *name, int value) |
| { |
| PyObject *v = PyInt_FromLong((long) value); |
| if (v == NULL) { |
| /* Don't bother reporting this error */ |
| PyErr_Clear(); |
| } |
| else { |
| PyDict_SetItemString(d, name, v); |
| Py_DECREF(v); |
| } |
| } |
| |
| DL_EXPORT(void) |
| initselect(void) |
| { |
| PyObject *m, *d; |
| m = Py_InitModule3("select", select_methods, module_doc); |
| d = PyModule_GetDict(m); |
| SelectError = PyErr_NewException("select.error", NULL, NULL); |
| PyDict_SetItemString(d, "error", SelectError); |
| #ifdef HAVE_POLL |
| poll_Type.ob_type = &PyType_Type; |
| insint(d, "POLLIN", POLLIN); |
| insint(d, "POLLPRI", POLLPRI); |
| insint(d, "POLLOUT", POLLOUT); |
| insint(d, "POLLERR", POLLERR); |
| insint(d, "POLLHUP", POLLHUP); |
| insint(d, "POLLNVAL", POLLNVAL); |
| |
| #ifdef POLLRDNORM |
| insint(d, "POLLRDNORM", POLLRDNORM); |
| #endif |
| #ifdef POLLRDBAND |
| insint(d, "POLLRDBAND", POLLRDBAND); |
| #endif |
| #ifdef POLLWRNORM |
| insint(d, "POLLWRNORM", POLLWRNORM); |
| #endif |
| #ifdef POLLWRBAND |
| insint(d, "POLLWRBAND", POLLWRBAND); |
| #endif |
| #ifdef POLLMSG |
| insint(d, "POLLMSG", POLLMSG); |
| #endif |
| #endif /* HAVE_POLL */ |
| } |