1 /**
2 * @file xcb_apps.c
3 * @brief List of application windows XCB module for VLC media player
4 */
5 /*****************************************************************************
6 * Copyright © 2009 Rémi Denis-Courmont
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU Lesser General Public License as published by
10 * the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this program; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
21 *****************************************************************************/
22
23 #ifdef HAVE_CONFIG_H
24 # include <config.h>
25 #endif
26 #include <stdarg.h>
27 #include <xcb/xcb.h>
28 typedef xcb_atom_t Atom;
29 #include <X11/Xatom.h> /* XA_WINDOW */
30 #include <vlc_common.h>
31 #include <vlc_services_discovery.h>
32 #include <vlc_dialog.h>
33 #include <vlc_charset.h>
34 #include <vlc_plugin.h>
35 #ifdef HAVE_SEARCH_H
36 # include <search.h>
37 #endif
38 #include <poll.h>
39
40 static int Open (vlc_object_t *);
41 static void Close (vlc_object_t *);
42 static int vlc_sd_probe_Open (vlc_object_t *);
43
44 /*
45 * Module descriptor
46 */
47 vlc_module_begin ()
48 set_shortname (N_("Screen capture"))
49 set_description (N_("Screen capture"))
50 set_category (CAT_PLAYLIST)
51 set_subcategory (SUBCAT_PLAYLIST_SD)
52 set_capability ("services_discovery", 0)
53 set_callbacks (Open, Close)
54
55 add_shortcut ("apps", "screen")
56
57 VLC_SD_PROBE_SUBMODULE
58 vlc_module_end ()
59
60 struct services_discovery_sys_t
61 {
62 xcb_connection_t *conn;
63 vlc_thread_t thread;
64 xcb_atom_t net_client_list;
65 xcb_atom_t net_wm_name;
66 xcb_window_t root_window;
67 void *apps;
68 input_item_t *apps_root;
69 };
70
71 static void *Run (void *);
72 static void UpdateApps (services_discovery_t *);
73 static void DelApp (void *);
74 static void AddDesktop(services_discovery_t *);
75
vlc_sd_probe_Open(vlc_object_t * obj)76 static int vlc_sd_probe_Open (vlc_object_t *obj)
77 {
78 vlc_probe_t *probe = (vlc_probe_t *)obj;
79
80 char *display = var_InheritString (obj, "x11-display");
81 xcb_connection_t *conn = xcb_connect (display, NULL);
82 free (display);
83 if (xcb_connection_has_error (conn))
84 return VLC_PROBE_CONTINUE;
85 xcb_disconnect (conn);
86 return vlc_sd_probe_Add (probe, "xcb_apps",
87 N_("Screen capture"), SD_CAT_DEVICES);
88 }
89
90 /**
91 * Probes and initializes.
92 */
Open(vlc_object_t * obj)93 static int Open (vlc_object_t *obj)
94 {
95 services_discovery_t *sd = (services_discovery_t *)obj;
96 services_discovery_sys_t *p_sys = malloc (sizeof (*p_sys));
97
98 if (p_sys == NULL)
99 return VLC_ENOMEM;
100 sd->p_sys = p_sys;
101 sd->description = _("Screen capture");
102
103 /* Connect to X server */
104 char *display = var_InheritString (obj, "x11-display");
105 int snum;
106 xcb_connection_t *conn = xcb_connect (display, &snum);
107 free (display);
108 if (xcb_connection_has_error (conn))
109 {
110 free (p_sys);
111 return VLC_EGENERIC;
112 }
113 p_sys->conn = conn;
114
115 /* Find configured screen */
116 const xcb_setup_t *setup = xcb_get_setup (conn);
117 const xcb_screen_t *scr = NULL;
118 for (xcb_screen_iterator_t i = xcb_setup_roots_iterator (setup);
119 i.rem > 0; xcb_screen_next (&i))
120 {
121 if (snum == 0)
122 {
123 scr = i.data;
124 break;
125 }
126 snum--;
127 }
128 if (scr == NULL)
129 {
130 msg_Err (obj, "bad X11 screen number");
131 goto error;
132 }
133
134 /* Add a permanent item for the entire desktop */
135 AddDesktop (sd);
136
137 p_sys->root_window = scr->root;
138 xcb_change_window_attributes (conn, scr->root, XCB_CW_EVENT_MASK,
139 &(uint32_t) { XCB_EVENT_MASK_PROPERTY_CHANGE });
140
141 /* TODO: check that _NET_CLIENT_LIST is in _NET_SUPPORTED
142 * (and _NET_SUPPORTING_WM_CHECK) */
143 xcb_intern_atom_reply_t *r;
144 xcb_intern_atom_cookie_t ncl, nwn;
145
146 ncl = xcb_intern_atom (conn, 1, strlen ("_NET_CLIENT_LIST"),
147 "_NET_CLIENT_LIST");
148 nwn = xcb_intern_atom (conn, 0, strlen ("_NET_WM_NAME"), "_NET_WM_NAME");
149
150 r = xcb_intern_atom_reply (conn, ncl, NULL);
151 if (r == NULL || r->atom == 0)
152 {
153 vlc_dialog_display_error (sd, _("Screen capture"),
154 _("Your window manager does not provide a list of applications."));
155 msg_Err (sd, "client list not supported (_NET_CLIENT_LIST absent)");
156 }
157 p_sys->net_client_list = r ? r->atom : 0;
158 free (r);
159 r = xcb_intern_atom_reply (conn, nwn, NULL);
160 if (r != NULL)
161 {
162 p_sys->net_wm_name = r->atom;
163 free (r);
164 }
165
166 p_sys->apps = NULL;
167 p_sys->apps_root = input_item_NewExt("vlc://nop", _("Applications"), -1,
168 ITEM_TYPE_NODE, ITEM_LOCAL);
169 if (likely(p_sys->apps_root != NULL))
170 services_discovery_AddItem(sd, p_sys->apps_root);
171
172 UpdateApps (sd);
173
174 if (vlc_clone (&p_sys->thread, Run, sd, VLC_THREAD_PRIORITY_LOW))
175 goto error;
176 return VLC_SUCCESS;
177
178 error:
179 xcb_disconnect (p_sys->conn);
180 tdestroy (p_sys->apps, DelApp);
181 if (p_sys->apps_root != NULL)
182 input_item_Release(p_sys->apps_root);
183 free (p_sys);
184 return VLC_EGENERIC;
185 }
186
187
188 /**
189 * Releases resources
190 */
Close(vlc_object_t * obj)191 static void Close (vlc_object_t *obj)
192 {
193 services_discovery_t *sd = (services_discovery_t *)obj;
194 services_discovery_sys_t *p_sys = sd->p_sys;
195
196 vlc_cancel (p_sys->thread);
197 vlc_join (p_sys->thread, NULL);
198 xcb_disconnect (p_sys->conn);
199 tdestroy (p_sys->apps, DelApp);
200 if (p_sys->apps_root != NULL)
201 input_item_Release(p_sys->apps_root);
202 free (p_sys);
203 }
204
Run(void * data)205 static void *Run (void *data)
206 {
207 services_discovery_t *sd = data;
208 services_discovery_sys_t *p_sys = sd->p_sys;
209 xcb_connection_t *conn = p_sys->conn;
210 int fd = xcb_get_file_descriptor (conn);
211 if (fd == -1)
212 return NULL;
213
214 while (!xcb_connection_has_error (conn))
215 {
216 xcb_generic_event_t *ev;
217 struct pollfd ufd = { .fd = fd, .events = POLLIN, };
218
219 poll (&ufd, 1, -1);
220
221 int canc = vlc_savecancel ();
222 while ((ev = xcb_poll_for_event (conn)) != NULL)
223 {
224 if ((ev->response_type & 0x7F) == XCB_PROPERTY_NOTIFY)
225 {
226 const xcb_property_notify_event_t *pn =
227 (xcb_property_notify_event_t *)ev;
228 if (pn->atom == p_sys->net_client_list)
229 UpdateApps (sd);
230 }
231 free (ev);
232 }
233 vlc_restorecancel (canc);
234 }
235 return NULL;
236 }
237
238 /*** Application windows ***/
239 struct app
240 {
241 xcb_window_t xid; /* must be first for cmpapp */
242 input_item_t *item;
243 services_discovery_t *owner;
244 };
245
AddApp(services_discovery_t * sd,xcb_window_t xid)246 static struct app *AddApp (services_discovery_t *sd, xcb_window_t xid)
247 {
248 services_discovery_sys_t *p_sys = sd->p_sys;
249 char *mrl, *name;
250
251 if (asprintf (&mrl, "window://0x%"PRIx8, xid) == -1)
252 return NULL;
253
254 xcb_get_property_reply_t *r =
255 xcb_get_property_reply (p_sys->conn,
256 xcb_get_property (p_sys->conn, 0, xid, p_sys->net_wm_name, 0,
257 0, 1023 /* max size */), NULL);
258 if (r != NULL)
259 {
260 name = strndup (xcb_get_property_value (r),
261 xcb_get_property_value_length (r));
262 if (name != NULL)
263 EnsureUTF8 (name); /* don't trust third party apps too much ;-) */
264 free (r);
265 }
266 /* TODO: use WM_NAME (Latin-1) for very old apps */
267 else
268 name = NULL;
269
270 input_item_t *item = input_item_NewCard (mrl, name ? name : mrl); /* FIXME */
271 free (mrl);
272 free (name);
273 if (item == NULL)
274 return NULL;
275
276 struct app *app = malloc (sizeof (*app));
277 if (app == NULL)
278 {
279 input_item_Release (item);
280 return NULL;
281 }
282 app->xid = xid;
283 app->item = item;
284 app->owner = sd;
285 services_discovery_AddSubItem(sd, p_sys->apps_root, item);
286 return app;
287 }
288
DelApp(void * data)289 static void DelApp (void *data)
290 {
291 struct app *app = data;
292
293 services_discovery_RemoveItem (app->owner, app->item);
294 input_item_Release (app->item);
295 free (app);
296 }
297
cmpapp(const void * a,const void * b)298 static int cmpapp (const void *a, const void *b)
299 {
300 xcb_window_t wa = *(xcb_window_t *)a;
301 xcb_window_t wb = *(xcb_window_t *)b;
302
303 if (wa > wb)
304 return 1;
305 if (wa < wb)
306 return -1;
307 return 0;
308 }
309
UpdateApps(services_discovery_t * sd)310 static void UpdateApps (services_discovery_t *sd)
311 {
312 services_discovery_sys_t *p_sys = sd->p_sys;
313 xcb_connection_t *conn = p_sys->conn;
314
315 xcb_get_property_reply_t *r =
316 xcb_get_property_reply (conn,
317 xcb_get_property (conn, false, p_sys->root_window,
318 p_sys->net_client_list, XA_WINDOW, 0, 1024),
319 NULL);
320 if (r == NULL)
321 return; /* FIXME: remove all entries */
322
323 xcb_window_t *ent = xcb_get_property_value (r);
324 int n = xcb_get_property_value_length (r) / 4;
325 void *newnodes = NULL, *oldnodes = p_sys->apps;
326
327 for (int i = 0; i < n; i++)
328 {
329 xcb_window_t id = *(ent++);
330 struct app *app;
331
332 struct app **pa = tfind (&id, &oldnodes, cmpapp);
333 if (pa != NULL) /* existing entry */
334 {
335 app = *pa;
336 tdelete (app, &oldnodes, cmpapp);
337 }
338 else /* new entry */
339 {
340 app = AddApp (sd, id);
341 if (app == NULL)
342 continue;
343 }
344
345 pa = tsearch (app, &newnodes, cmpapp);
346 if (pa == NULL /* OOM */ || *pa != app /* buggy window manager */)
347 DelApp (app);
348 }
349 free (r);
350
351 /* Remove old nodes */
352 tdestroy (oldnodes, DelApp);
353 p_sys->apps = newnodes;
354 }
355
356 /*** Whole desktop ***/
AddDesktop(services_discovery_t * sd)357 static void AddDesktop(services_discovery_t *sd)
358 {
359 input_item_t *item;
360
361 item = input_item_NewCard ("screen://", _("Desktop"));
362 if (item == NULL)
363 return;
364
365 services_discovery_AddItem(sd, item);
366 input_item_Release (item);
367 }
368