qemu/ui/dbus-chardev.c
Marc-André Lureau 3e301c8d7e ui/dbus: add chardev backend & interface
Add a new chardev backend which allows D-Bus client to handle the
chardev stream & events.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2021-12-21 10:50:22 +04:00

297 lines
8.1 KiB
C

/*
* QEMU DBus display
*
* Copyright (c) 2021 Marc-André Lureau <marcandre.lureau@redhat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "trace.h"
#include "qapi/error.h"
#include "qemu/config-file.h"
#include "qemu/option.h"
#include <gio/gunixfdlist.h>
#include "dbus.h"
static char *
dbus_display_chardev_path(DBusChardev *chr)
{
return g_strdup_printf(DBUS_DISPLAY1_ROOT "/Chardev_%s",
CHARDEV(chr)->label);
}
static void
dbus_display_chardev_export(DBusDisplay *dpy, DBusChardev *chr)
{
g_autoptr(GDBusObjectSkeleton) sk = NULL;
g_autofree char *path = dbus_display_chardev_path(chr);
if (chr->exported) {
return;
}
sk = g_dbus_object_skeleton_new(path);
g_dbus_object_skeleton_add_interface(
sk, G_DBUS_INTERFACE_SKELETON(chr->iface));
g_dbus_object_manager_server_export(dpy->server, sk);
chr->exported = true;
}
static void
dbus_display_chardev_unexport(DBusDisplay *dpy, DBusChardev *chr)
{
g_autofree char *path = dbus_display_chardev_path(chr);
if (!chr->exported) {
return;
}
g_dbus_object_manager_server_unexport(dpy->server, path);
chr->exported = false;
}
static int
dbus_display_chardev_foreach(Object *obj, void *data)
{
DBusDisplay *dpy = DBUS_DISPLAY(data);
if (!CHARDEV_IS_DBUS(obj)) {
return 0;
}
dbus_display_chardev_export(dpy, DBUS_CHARDEV(obj));
return 0;
}
static void
dbus_display_on_notify(Notifier *notifier, void *data)
{
DBusDisplay *dpy = container_of(notifier, DBusDisplay, notifier);
DBusDisplayEvent *event = data;
switch (event->type) {
case DBUS_DISPLAY_CHARDEV_OPEN:
dbus_display_chardev_export(dpy, event->chardev);
break;
case DBUS_DISPLAY_CHARDEV_CLOSE:
dbus_display_chardev_unexport(dpy, event->chardev);
break;
}
}
void
dbus_chardev_init(DBusDisplay *dpy)
{
dpy->notifier.notify = dbus_display_on_notify;
dbus_display_notifier_add(&dpy->notifier);
object_child_foreach(container_get(object_get_root(), "/chardevs"),
dbus_display_chardev_foreach, dpy);
}
static gboolean
dbus_chr_register(
DBusChardev *dc,
GDBusMethodInvocation *invocation,
GUnixFDList *fd_list,
GVariant *arg_stream,
QemuDBusDisplay1Chardev *object)
{
g_autoptr(GError) err = NULL;
int fd;
fd = g_unix_fd_list_get(fd_list, g_variant_get_handle(arg_stream), &err);
if (err) {
g_dbus_method_invocation_return_error(
invocation,
DBUS_DISPLAY_ERROR,
DBUS_DISPLAY_ERROR_FAILED,
"Couldn't get peer FD: %s", err->message);
return DBUS_METHOD_INVOCATION_HANDLED;
}
if (qemu_chr_add_client(CHARDEV(dc), fd) < 0) {
g_dbus_method_invocation_return_error(invocation,
DBUS_DISPLAY_ERROR,
DBUS_DISPLAY_ERROR_FAILED,
"Couldn't register FD!");
close(fd);
return DBUS_METHOD_INVOCATION_HANDLED;
}
g_object_set(dc->iface,
"owner", g_dbus_method_invocation_get_sender(invocation),
NULL);
qemu_dbus_display1_chardev_complete_register(object, invocation, NULL);
return DBUS_METHOD_INVOCATION_HANDLED;
}
static gboolean
dbus_chr_send_break(
DBusChardev *dc,
GDBusMethodInvocation *invocation,
QemuDBusDisplay1Chardev *object)
{
qemu_chr_be_event(CHARDEV(dc), CHR_EVENT_BREAK);
qemu_dbus_display1_chardev_complete_send_break(object, invocation);
return DBUS_METHOD_INVOCATION_HANDLED;
}
static void
dbus_chr_open(Chardev *chr, ChardevBackend *backend,
bool *be_opened, Error **errp)
{
ERRP_GUARD();
DBusChardev *dc = DBUS_CHARDEV(chr);
DBusDisplayEvent event = {
.type = DBUS_DISPLAY_CHARDEV_OPEN,
.chardev = dc,
};
g_autoptr(ChardevBackend) be = NULL;
g_autoptr(QemuOpts) opts = NULL;
dc->iface = qemu_dbus_display1_chardev_skeleton_new();
g_object_set(dc->iface, "name", backend->u.dbus.data->name, NULL);
g_object_connect(dc->iface,
"swapped-signal::handle-register",
dbus_chr_register, dc,
"swapped-signal::handle-send-break",
dbus_chr_send_break, dc,
NULL);
dbus_display_notify(&event);
be = g_new0(ChardevBackend, 1);
opts = qemu_opts_create(qemu_find_opts("chardev"), NULL, 0, &error_abort);
qemu_opt_set(opts, "server", "on", &error_abort);
qemu_opt_set(opts, "wait", "off", &error_abort);
CHARDEV_CLASS(object_class_by_name(TYPE_CHARDEV_SOCKET))->parse(
opts, be, errp);
if (*errp) {
return;
}
CHARDEV_CLASS(object_class_by_name(TYPE_CHARDEV_SOCKET))->open(
chr, be, be_opened, errp);
}
static void
dbus_chr_set_fe_open(Chardev *chr, int fe_open)
{
DBusChardev *dc = DBUS_CHARDEV(chr);
g_object_set(dc->iface, "feopened", fe_open, NULL);
}
static void
dbus_chr_set_echo(Chardev *chr, bool echo)
{
DBusChardev *dc = DBUS_CHARDEV(chr);
g_object_set(dc->iface, "echo", echo, NULL);
}
static void
dbus_chr_be_event(Chardev *chr, QEMUChrEvent event)
{
DBusChardev *dc = DBUS_CHARDEV(chr);
DBusChardevClass *klass = DBUS_CHARDEV_GET_CLASS(chr);
switch (event) {
case CHR_EVENT_CLOSED:
if (dc->iface) {
/* on finalize, iface is set to NULL */
g_object_set(dc->iface, "owner", "", NULL);
}
break;
default:
break;
};
klass->parent_chr_be_event(chr, event);
}
static void
dbus_chr_parse(QemuOpts *opts, ChardevBackend *backend,
Error **errp)
{
const char *name = qemu_opt_get(opts, "name");
ChardevDBus *dbus;
if (name == NULL) {
error_setg(errp, "chardev: dbus: no name given");
return;
}
backend->type = CHARDEV_BACKEND_KIND_DBUS;
dbus = backend->u.dbus.data = g_new0(ChardevDBus, 1);
qemu_chr_parse_common(opts, qapi_ChardevDBus_base(dbus));
dbus->name = g_strdup(name);
}
static void
char_dbus_class_init(ObjectClass *oc, void *data)
{
DBusChardevClass *klass = DBUS_CHARDEV_CLASS(oc);
ChardevClass *cc = CHARDEV_CLASS(oc);
cc->parse = dbus_chr_parse;
cc->open = dbus_chr_open;
cc->chr_set_fe_open = dbus_chr_set_fe_open;
cc->chr_set_echo = dbus_chr_set_echo;
klass->parent_chr_be_event = cc->chr_be_event;
cc->chr_be_event = dbus_chr_be_event;
}
static void
char_dbus_finalize(Object *obj)
{
DBusChardev *dc = DBUS_CHARDEV(obj);
DBusDisplayEvent event = {
.type = DBUS_DISPLAY_CHARDEV_CLOSE,
.chardev = dc,
};
dbus_display_notify(&event);
g_clear_object(&dc->iface);
}
static const TypeInfo char_dbus_type_info = {
.name = TYPE_CHARDEV_DBUS,
.parent = TYPE_CHARDEV_SOCKET,
.class_size = sizeof(DBusChardevClass),
.instance_size = sizeof(DBusChardev),
.instance_finalize = char_dbus_finalize,
.class_init = char_dbus_class_init,
};
module_obj(TYPE_CHARDEV_DBUS);
static void
register_types(void)
{
type_register_static(&char_dbus_type_info);
}
type_init(register_types);