path: root/_dbus_bindings/mainloop.c

/* Implementation of main-loop integration for dbus-python.
 *
 * Copyright (C) 2006 Collabora Ltd.
 *
 * Licensed under the Academic Free License version 2.1
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "config.h"

#include "dbus_bindings-internal.h"

#ifndef HAVE_DBUS_WATCH_GET_UNIX_FD
#   define dbus_watch_get_unix_fd dbus_watch_get_fd
#endif

/* Watch ============================================================ */

PyDoc_STRVAR(Watch_tp_doc,
"Object representing a watched file descriptor.\n"
"Cannot be instantiated from Python.\n"
);

static PyTypeObject Watch_Type;

DEFINE_CHECK(Watch)

typedef struct {
    PyObject_HEAD
    DBusWatch *watch;
} Watch;

PyDoc_STRVAR(Watch_fileno__doc__,
"fileno() -> int\n\n"
"Return the watched file descriptor.\n");
static PyObject *
Watch_fileno(Watch *self, PyObject *unused UNUSED)
{
    int fd;

    if (!self->watch) {
        DBG("Attempted fileno() on broken Watch at %p", self);
        PyErr_SetString(PyExc_ValueError, "FD watch is no longer valid");
        return NULL;
    }
    fd = dbus_watch_get_unix_fd(self->watch);
    DBG("Watch at %p (wrapping DBusWatch at %p) has fileno %d", self,
        self->watch, fd);
    return PyInt_FromLong(fd);
}

PyDoc_STRVAR(Watch_get_flags__doc__,
"get_flags() -> int\n\n"
"Return 0, WATCH_READABLE, WATCH_WRITABLE or WATCH_READABLE|WATCH_WRITABLE.\n");
static PyObject *
Watch_get_flags(Watch *self, PyObject *unused UNUSED)
{
    unsigned int flags;

    if (!self->watch) {
        DBG("Attempted get_flags() on broken Watch at %p", self);
        PyErr_SetString(PyExc_ValueError, "FD watch is no longer valid");
        return NULL;
    }
    flags = dbus_watch_get_flags(self->watch);
    DBG("Watch at %p (wrapping DBusWatch at %p) has flags 0x%x (%s,%s)",
        self, self->watch, flags, flags & DBUS_WATCH_READABLE ? "read" : ".",
        flags & DBUS_WATCH_WRITABLE ? "write" : ".");
    return PyInt_FromLong((long)flags);
}

PyDoc_STRVAR(Watch_get_enabled__doc__,
"get_enabled() -> bool\n\n"
"Return True if this watch is currently active.\n");
static PyObject *
Watch_get_enabled(Watch *self, PyObject *unused UNUSED)
{
    dbus_bool_t enabled;

    if (!self->watch) {
        DBG("Attempted get_enabled() on broken Watch at %p", self);
        PyErr_SetString(PyExc_ValueError, "FD watch is no longer valid");
        return NULL;
    }
    enabled = dbus_watch_get_enabled(self->watch);
    DBG("Watch at %p (wrapping DBusWatch at %p) is %s", self,
        self->watch, enabled ? "enabled" : "disabled");
    return PyBool_FromLong(enabled);
}

PyDoc_STRVAR(Watch_handle__doc__,
"handle(flags)\n\n"
"To be called when the file descriptor is closed or reports error,\n"
"or enters a readable/writable state for which notification is required\n"
"(according to get_flags()).");
static PyObject *
Watch_handle(Watch *self, PyObject *args)
{
    unsigned int flags;
    if (!self->watch) {
        DBG("Attempted handle() on broken Watch at %p", self);
        PyErr_SetString(PyExc_ValueError, "FD watch is no longer valid");
        return NULL;
    }
    if (!PyArg_ParseTuple(args, "i", &flags)) {
        DBG("Python passed junk to <Watch at %p>.handle()", self);
        return NULL;
    }
    DBG("Watch at %p (wrapping DBusWatch at %p) handle(0x%x) (%s,%s)",
        self, self->watch, flags, flags & DBUS_WATCH_READABLE ? "read" : ".",
        flags & DBUS_WATCH_WRITABLE ? "write" : ".");
    Py_BEGIN_ALLOW_THREADS
    dbus_watch_handle(self->watch, (unsigned int)flags);
    Py_END_ALLOW_THREADS
    Py_RETURN_NONE;
}

/* Arranges for the watch to be referenced by its corresponding DBusWatch.
 * Returns a borrowed reference, or NULL with a Python exception.
 */
static PyObject *
Watch_BorrowFromDBusWatch(DBusWatch *watch, PyObject *mainloop)
{
    Watch *self = (Watch *)dbus_watch_get_data(watch);

    if (self)
        return (PyObject *)self;
    if (!mainloop) {
        PyErr_SetString(PyExc_AssertionError,
                        "Attempted to use a non-added watch");
        return NULL;
    }

    self = PyObject_New(Watch, &Watch_Type);
    if (!self) {
        return NULL;
    }
    self->watch = watch;

    Py_INCREF(self);
    dbus_watch_set_data(watch, self,
                        (DBusFreeFunction)dbus_py_take_gil_and_xdecref);
    return (PyObject *)self;
}

static PyMethodDef Watch_tp_methods[] = {
    {"fileno", (PyCFunction)Watch_fileno, METH_NOARGS,
     Watch_fileno__doc__},
    {"get_flags", (PyCFunction)Watch_get_flags, METH_NOARGS,
     Watch_get_flags__doc__},
    {"handle", (PyCFunction)Watch_handle, METH_VARARGS,
     Watch_handle__doc__},
    {"get_enabled", (PyCFunction)Watch_get_enabled, METH_NOARGS,
     Watch_get_enabled__doc__},
    {NULL, NULL, 0, NULL}
};

static void Watch_tp_dealloc(PyObject *self)
{
    PyObject_Del(self);
}

static PyTypeObject Watch_Type = {
    PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
    0,
    "_dbus_bindings.Watch",
    sizeof(Watch),
    0,
    Watch_tp_dealloc,                       /* tp_dealloc */
    0,                                      /* tp_print */
    0,                                      /* tp_getattr */
    0,                                      /* tp_setattr */
    0,                                      /* tp_compare */
    0,                                      /* tp_repr */
    0,                                      /* tp_as_number */
    0,                                      /* tp_as_sequence */
    0,                                      /* tp_as_mapping */
    dbus_py_tp_hash_by_pointer,             /* tp_hash */
    0,                                      /* tp_call */
    0,                                      /* tp_str */
    0,                                      /* tp_getattro */
    0,                                      /* tp_setattro */
    0,                                      /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT,                     /* tp_flags */
    Watch_tp_doc,                           /* tp_doc */
    0,                                      /* tp_traverse */
    0,                                      /* tp_clear */
    dbus_py_tp_richcompare_by_pointer,      /* tp_richcompare */
    0,                                      /* tp_weaklistoffset */
    0,                                      /* tp_iter */
    0,                                      /* tp_iternext */
    Watch_tp_methods,                       /* tp_methods */
    0,                                      /* 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 */
    /* deliberately not callable! */
    0,                                      /* tp_new */
};

/* Timeout ========================================================== */

PyDoc_STRVAR(Timeout_tp_doc,
"Object representing a watched file descriptor.\n"
"Cannot be instantiated from Python.\n"
);

static PyTypeObject Timeout_Type;

DEFINE_CHECK(Timeout)

typedef struct {
    PyObject_HEAD
    DBusTimeout *timeout;
} Timeout;

PyDoc_STRVAR(Timeout_get_interval__doc__,
"get_interval() -> float\n\n"
"Return the interval in seconds.\n");
static PyObject *
Timeout_get_interval(Timeout *self, PyObject *unused UNUSED)
{
    double interval;
    if (!self->timeout) {
        DBG("Attempted get_interval() on broken Timeout at %p", self);
        PyErr_SetString(PyExc_ValueError, "Timeout object is no longer valid");
        return NULL;
    }
    interval = ((double)dbus_timeout_get_interval(self->timeout)) / 1000.0;
    DBG("Timeout at %p (wrapping DBusTimeout at %p) has interval %f s", self,
        self->timeout, interval);
    return PyFloat_FromDouble(interval);
}

PyDoc_STRVAR(Timeout_get_enabled__doc__,
"get_enabled() -> bool\n\n"
"Return True if this timeout is currently active.\n");
static PyObject *
Timeout_get_enabled(Timeout *self, PyObject *unused UNUSED)
{
    dbus_bool_t enabled;

    if (!self->timeout) {
        DBG("Attempted get_enabled() on broken Timeout at %p", self);
        PyErr_SetString(PyExc_ValueError, "Timeout object is no longer valid");
        return NULL;
    }
    enabled = dbus_timeout_get_enabled(self->timeout);
    DBG("Timeout at %p (wrapping DBusTimeout at %p) is %s", self,
        self->timeout, enabled ? "enabled" : "disabled");
    return PyBool_FromLong(enabled);
}

PyDoc_STRVAR(Timeout_handle__doc__,
"handle()\n\n"
"To be called when timeout occurs.\n");
static PyObject *
Timeout_handle(Timeout *self, PyObject *unused UNUSED)
{
    if (!self->timeout) {
        DBG("Attempted handle() on broken Timeout at %p", self);
        PyErr_SetString(PyExc_ValueError, "Timeout object is no longer valid");
        return NULL;
    }
    DBG("Timeout_handle() with self->timeout=%p", self->timeout);
    Py_BEGIN_ALLOW_THREADS
    dbus_timeout_handle(self->timeout);
    Py_END_ALLOW_THREADS
    Py_RETURN_NONE;
}

/* Returns a borrowed reference */
static PyObject *
Timeout_BorrowFromDBusTimeout(DBusTimeout *timeout, PyObject *mainloop)
{
    Timeout *self = (Timeout *)dbus_timeout_get_data(timeout);
    if (self)
        return (PyObject *)self;
    if (!mainloop) {
        PyErr_SetString(PyExc_AssertionError,
                        "Attempted to use a non-added timeout");
        return NULL;
    }

    self = PyObject_New(Timeout, &Timeout_Type);
    if (!self) {
        return NULL;
    }
    self->timeout = timeout;

    Py_INCREF(self);
    dbus_timeout_set_data(timeout, self,
                          (DBusFreeFunction)dbus_py_take_gil_and_xdecref);
    return (PyObject *)self;
}

static PyMethodDef Timeout_tp_methods[] = {
    {"get_interval", (PyCFunction)Timeout_get_interval, METH_NOARGS,
     Timeout_get_interval__doc__},
    {"handle", (PyCFunction)Timeout_handle, METH_NOARGS,
     Timeout_handle__doc__},
    {"get_enabled", (PyCFunction)Timeout_get_enabled, METH_NOARGS,
     Timeout_get_enabled__doc__},
    {NULL, NULL, 0, NULL}
};

static void Timeout_tp_dealloc(PyObject *self)
{
    PyObject_Del(self);
}

static PyTypeObject Timeout_Type = {
    PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
    0,
    "_dbus_bindings.Timeout",
    sizeof(Timeout),
    0,
    Timeout_tp_dealloc,                     /* tp_dealloc */
    0,                                      /* tp_print */
    0,                                      /* tp_getattr */
    0,                                      /* tp_setattr */
    0,                                      /* tp_compare */
    0,                                      /* tp_repr */
    0,                                      /* tp_as_number */
    0,                                      /* tp_as_sequence */
    0,                                      /* tp_as_mapping */
    dbus_py_tp_hash_by_pointer,             /* tp_hash */
    0,                                      /* tp_call */
    0,                                      /* tp_str */
    0,                                      /* tp_getattro */
    0,                                      /* tp_setattro */
    0,                                      /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT,                     /* tp_flags */
    Timeout_tp_doc,                         /* tp_doc */
    0,                                      /* tp_traverse */
    0,                                      /* tp_clear */
    dbus_py_tp_richcompare_by_pointer,      /* tp_richcompare */
    0,                                      /* tp_weaklistoffset */
    0,                                      /* tp_iter */
    0,                                      /* tp_iternext */
    Timeout_tp_methods,                     /* tp_methods */
    0,                                      /* 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 */
    /* deliberately not callable! */
    0,                                      /* tp_new */
};

/* Native mainloop wrapper ========================================= */

PyDoc_STRVAR(NativeMainLoop_tp_doc,
"Object representing D-Bus main loop integration done in native code.\n"
"Cannot be instantiated directly.\n"
);

static PyTypeObject NativeMainLoop_Type;

DEFINE_CHECK(NativeMainLoop)

typedef struct {
    PyObject_HEAD
    /* Called with the GIL held, should set a Python exception on error */
    dbus_bool_t (*set_up_connection_cb)(DBusConnection *, void *);
    dbus_bool_t (*set_up_server_cb)(DBusServer *, void *);
    /* Called in a destructor. Must not touch the exception state (use
     * PyErr_Fetch and PyErr_Restore if necessary). */
    void (*free_cb)(void *);
    void *data;
} NativeMainLoop;

static void NativeMainLoop_tp_dealloc(NativeMainLoop *self)
{
    if (self->data && self->free_cb) {
        (self->free_cb)(self->data);
    }
    PyObject_Del((PyObject *)self);
}

static PyTypeObject NativeMainLoop_Type = {
    PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
    0,
    "dbus.mainloop.NativeMainLoop",
    sizeof(NativeMainLoop),
    0,
    (destructor)NativeMainLoop_tp_dealloc,  /* tp_dealloc */
    0,                                      /* tp_print */
    0,                                      /* 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 */
    0,                                      /* tp_call */
    0,                                      /* tp_str */
    0,                                      /* tp_getattro */
    0,                                      /* tp_setattro */
    0,                                      /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT,                     /* tp_flags */
    NativeMainLoop_tp_doc,                  /* tp_doc */
    0,                                      /* tp_traverse */
    0,                                      /* tp_clear */
    0,                                      /* tp_richcompare */
    0,                                      /* tp_weaklistoffset */
    0,                                      /* tp_iter */
    0,                                      /* tp_iternext */
    0,                                      /* tp_methods */
    0,                                      /* 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 */
    /* deliberately not callable! */
    0,                                      /* tp_new */
};

/* Internal C API for Connection, Bus, Server ======================= */

dbus_bool_t
dbus_py_check_mainloop_sanity(PyObject *mainloop)
{
    if (NativeMainLoop_Check(mainloop)) {
        return TRUE;
    }
    PyErr_SetString(PyExc_TypeError,
                    "A dbus.mainloop.NativeMainLoop instance is required");
    return FALSE;
}

dbus_bool_t
dbus_py_set_up_connection(PyObject *conn, PyObject *mainloop)
{
    if (NativeMainLoop_Check(mainloop)) {
        /* Native mainloops are allowed to do arbitrary strange things */
        NativeMainLoop *nml = (NativeMainLoop *)mainloop;
        DBusConnection *dbc = DBusPyConnection_BorrowDBusConnection(conn);

        if (!dbc) {
            return FALSE;
        }
        return (nml->set_up_connection_cb)(dbc, nml->data);
    }
    PyErr_SetString(PyExc_TypeError,
                    "A dbus.mainloop.NativeMainLoop instance is required");
    return FALSE;
}

/* C API ============================================================ */

PyObject *
DBusPyNativeMainLoop_New4(dbus_bool_t (*conn_cb)(DBusConnection *, void *),
                          dbus_bool_t (*server_cb)(DBusServer *, void *),
                          void (*free_cb)(void *),
                          void *data)
{
    NativeMainLoop *self = PyObject_New(NativeMainLoop, &NativeMainLoop_Type);
    if (self) {
        self->data = data;
        self->free_cb = free_cb;
        self->set_up_connection_cb = conn_cb;
        self->set_up_server_cb = server_cb;
    }
    return (PyObject *)self;
}

/* Null mainloop implementation ===================================== */

static dbus_bool_t
noop_main_loop_cb(void *conn_or_server UNUSED, void *data UNUSED)
{
    return TRUE;
}

#define noop_conn_cb ((dbus_bool_t (*)(DBusConnection *, void *))(noop_main_loop_cb))
#define noop_server_cb ((dbus_bool_t (*)(DBusServer *, void *))(noop_main_loop_cb))

/* Initialization =================================================== */

dbus_bool_t
dbus_py_init_mainloop(void)
{
    if (PyType_Ready (&Watch_Type) < 0) return 0;
    if (PyType_Ready (&Timeout_Type) < 0) return 0;
    if (PyType_Ready (&NativeMainLoop_Type) < 0) return 0;

    /* placate -Wunused */
    (void)&Watch_BorrowFromDBusWatch;
    (void)&Timeout_BorrowFromDBusTimeout;

    return 1;
}

dbus_bool_t
dbus_py_insert_mainloop_types(PyObject *this_module)
{
    PyObject *null_main_loop = DBusPyNativeMainLoop_New4(noop_conn_cb,
                                                         noop_server_cb,
                                                         NULL,
                                                         NULL);
    if (!null_main_loop) return 0;

    if (PyModule_AddObject (this_module, "Watch",
                            (PyObject *)&Watch_Type) < 0) return 0;
    if (PyModule_AddObject (this_module, "Timeout",
                            (PyObject *)&Timeout_Type) < 0) return 0;
    if (PyModule_AddObject (this_module, "NativeMainLoop",
                            (PyObject *)&NativeMainLoop_Type) < 0) return 0;
    if (PyModule_AddObject (this_module, "NULL_MAIN_LOOP",
                            null_main_loop) < 0) return 0;
    return 1;
}

/* vim:set ft=c cino< sw=4 sts=4 et: */