console: add user console daemon

This adds a first draft of systemd-consoled. This is still missing a lot
of features and does some rather primitive rendering. However, it shows
the direction this code is going and serves as basis for further testing.

The systemd-consoled binary should be run as `systemd --user' unit. It
automatically picks up any session marked as Desktop=SYSTEMD-CONSOLE.
Therefore, you can use any login-manager you want (ranging from /bin/login
to gdm) to create sessions for systemd-consoled. However, the sessions
managers must be prepared to set the Desktop= variable properly.

The user-session is called `systemd-console', only the daemon providing
the terminal environment is called `systemd-consoled' (mind the 'd').

So far, only a single terminal session is provided on each opened
user-session. However, we support multiple user-sessions (even across
multiple seats) just fine. In the future, the workspace logic will get
extended so you can have multiple terminal sessions in a single
user-session for easier access.

Note that this is still experimental! Instructions on how to run it will
follow shortly.

1 files changed, 283 insertions, 0 deletions

diff --git a/src/console/consoled-session.c b/src/console/consoled-session.c
new file mode 100644
index 0000000000..8bacacab35
--- /dev/null
+++ b/src/console/consoled-session.c
@@ -0,0 +1,283 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 David Herrmann <dh.herrmann@gmail.com>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <inttypes.h>
+#include <libudev.h>
+#include <stdlib.h>
+#include "consoled.h"
+#include "grdev.h"
+#include "hashmap.h"
+#include "idev.h"
+#include "list.h"
+#include "macro.h"
+#include "sd-bus.h"
+#include "sd-event.h"
+#include "sysview.h"
+#include "util.h"
+
+static bool session_feed_keyboard(Session *s, idev_data *data) {
+        idev_data_keyboard *kdata = &data->keyboard;
+
+        if (!data->resync && kdata->value == 1 && kdata->n_syms == 1) {
+                uint32_t nr;
+                sysview_seat *seat;
+
+                /* handle VT-switch requests */
+                nr = 0;
+
+                switch (kdata->keysyms[0]) {
+                case XKB_KEY_F1 ... XKB_KEY_F12:
+                        if (IDEV_KBDMATCH(kdata,
+                                          IDEV_KBDMOD_CTRL | IDEV_KBDMOD_ALT,
+                                          kdata->keysyms[0]))
+                                nr = kdata->keysyms[0] - XKB_KEY_F1 + 1;
+                        break;
+                case XKB_KEY_XF86Switch_VT_1 ... XKB_KEY_XF86Switch_VT_12:
+                        nr = kdata->keysyms[0] - XKB_KEY_XF86Switch_VT_1 + 1;
+                        break;
+                }
+
+                if (nr != 0) {
+                        seat = sysview_session_get_seat(s->sysview);
+                        sysview_seat_switch_to(seat, nr);
+                        return true;
+                }
+        }
+
+        return false;
+}
+
+static bool session_feed(Session *s, idev_data *data) {
+        switch (data->type) {
+        case IDEV_DATA_KEYBOARD:
+                return session_feed_keyboard(s, data);
+        default:
+                return false;
+        }
+}
+
+static int session_idev_fn(idev_session *idev, void *userdata, idev_event *event) {
+        Session *s = userdata;
+
+        switch (event->type) {
+        case IDEV_EVENT_DEVICE_ADD:
+                idev_device_enable(event->device_add.device);
+                break;
+        case IDEV_EVENT_DEVICE_REMOVE:
+                idev_device_disable(event->device_remove.device);
+                break;
+        case IDEV_EVENT_DEVICE_DATA:
+                if (!session_feed(s, &event->device_data.data))
+                        workspace_feed(s->active_ws, &event->device_data.data);
+                break;
+        }
+
+        return 0;
+}
+
+static void session_grdev_fn(grdev_session *grdev, void *userdata, grdev_event *event) {
+        grdev_display *display;
+        Session *s = userdata;
+        Display *d;
+        int r;
+
+        switch (event->type) {
+        case GRDEV_EVENT_DISPLAY_ADD:
+                display = event->display_add.display;
+
+                r = display_new(&d, s, display);
+                if (r < 0) {
+                        log_error("Cannot create display '%s' on '%s': %s",
+                                  grdev_display_get_name(display), sysview_session_get_name(s->sysview), strerror(-r));
+                        break;
+                }
+
+                grdev_display_set_userdata(display, d);
+                workspace_refresh(s->active_ws);
+                break;
+        case GRDEV_EVENT_DISPLAY_REMOVE:
+                display = event->display_remove.display;
+                d = grdev_display_get_userdata(display);
+                if (!d)
+                        break;
+
+                display_free(d);
+                workspace_refresh(s->active_ws);
+                break;
+        case GRDEV_EVENT_DISPLAY_CHANGE:
+                display = event->display_remove.display;
+                d = grdev_display_get_userdata(display);
+                if (!d)
+                        break;
+
+                display_refresh(d);
+                workspace_refresh(s->active_ws);
+                break;
+        case GRDEV_EVENT_DISPLAY_FRAME:
+                display = event->display_remove.display;
+                d = grdev_display_get_userdata(display);
+                if (!d)
+                        break;
+
+                session_dirty(s);
+                break;
+        }
+}
+
+static int session_redraw_fn(sd_event_source *src, void *userdata) {
+        Session *s = userdata;
+        Display *d;
+
+        LIST_FOREACH(displays_by_session, d, s->display_list)
+                display_render(d, s->active_ws);
+
+        grdev_session_commit(s->grdev);
+
+        return 0;
+}
+
+int session_new(Session **out, Manager *m, sysview_session *session) {
+        _cleanup_(session_freep) Session *s = NULL;
+        int r;
+
+        assert(out);
+        assert(m);
+        assert(session);
+
+        s = new0(Session, 1);
+        if (!s)
+                return -ENOMEM;
+
+        s->manager = m;
+        s->sysview = session;
+
+        r = grdev_session_new(&s->grdev,
+                              m->grdev,
+                              GRDEV_SESSION_MANAGED,
+                              sysview_session_get_name(session),
+                              session_grdev_fn,
+                              s);
+        if (r < 0)
+                return r;
+
+        r = idev_session_new(&s->idev,
+                             m->idev,
+                             IDEV_SESSION_MANAGED,
+                             sysview_session_get_name(session),
+                             session_idev_fn,
+                             s);
+        if (r < 0)
+                return r;
+
+        r = workspace_new(&s->my_ws, m);
+        if (r < 0)
+                return r;
+
+        s->active_ws = workspace_attach(s->my_ws, s);
+
+        r = sd_event_add_defer(m->event, &s->redraw_src, session_redraw_fn, s);
+        if (r < 0)
+                return r;
+
+        grdev_session_enable(s->grdev);
+        idev_session_enable(s->idev);
+
+        *out = s;
+        s = NULL;
+        return 0;
+}
+
+Session *session_free(Session *s) {
+        if (!s)
+                return NULL;
+
+        assert(!s->display_list);
+
+        sd_event_source_unref(s->redraw_src);
+
+        workspace_detach(s->active_ws, s);
+        workspace_unref(s->my_ws);
+
+        idev_session_free(s->idev);
+        grdev_session_free(s->grdev);
+        free(s);
+
+        return NULL;
+}
+
+void session_dirty(Session *s) {
+        int r;
+
+        assert(s);
+
+        r = sd_event_source_set_enabled(s->redraw_src, SD_EVENT_ONESHOT);
+        if (r < 0)
+                log_error("Cannot enable redraw-source: %s", strerror(-r));
+}
+
+void session_add_device(Session *s, sysview_device *device) {
+        unsigned int type;
+
+        assert(s);
+        assert(device);
+
+        type = sysview_device_get_type(device);
+        switch (type) {
+        case SYSVIEW_DEVICE_DRM:
+                grdev_session_add_drm(s->grdev, sysview_device_get_ud(device));
+                break;
+        case SYSVIEW_DEVICE_EVDEV:
+                idev_session_add_evdev(s->idev, sysview_device_get_ud(device));
+                break;
+        }
+}
+
+void session_remove_device(Session *s, sysview_device *device) {
+        unsigned int type;
+
+        assert(s);
+        assert(device);
+
+        type = sysview_device_get_type(device);
+        switch (type) {
+        case SYSVIEW_DEVICE_DRM:
+                grdev_session_remove_drm(s->grdev, sysview_device_get_ud(device));
+                break;
+        case SYSVIEW_DEVICE_EVDEV:
+                idev_session_remove_evdev(s->idev, sysview_device_get_ud(device));
+                break;
+        }
+}
+
+void session_refresh_device(Session *s, sysview_device *device, struct udev_device *ud) {
+        unsigned int type;
+
+        assert(s);
+        assert(device);
+
+        type = sysview_device_get_type(device);
+        switch (type) {
+        case SYSVIEW_DEVICE_DRM:
+                grdev_session_hotplug_drm(s->grdev, sysview_device_get_ud(device));
+                break;
+        }
+}