2 * vim:ts=4:sw=4:expandtab
4 * i3 - an improved dynamic tiling window manager
5 * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
15 #include <xcb/xcb_event.h>
17 #include <X11/keysym.h>
19 typedef struct dialog_t {
21 xcb_colormap_t colormap;
29 static TAILQ_HEAD(dialogs_head, dialog_t) dialogs = TAILQ_HEAD_INITIALIZER(dialogs);
30 static int raised_signal;
31 static int backtrace_done = 0;
33 static int sighandler_backtrace(void);
34 static void sighandler_setup(void);
35 static void sighandler_create_dialogs(void);
36 static void sighandler_destroy_dialogs(void);
37 static void sighandler_handle_expose(void);
38 static void sighandler_draw_dialog(dialog_t *dialog);
39 static void sighandler_handle_key_press(xcb_key_press_event_t *event);
41 static i3String *message_intro;
42 static i3String *message_intro2;
43 static i3String *message_option_backtrace;
44 static i3String *message_option_restart;
45 static i3String *message_option_forget;
46 static int dialog_width;
47 static int dialog_height;
49 static int border_width = 2;
50 static int margin = 4;
53 * Attach gdb to pid_parent and dump a backtrace to i3-backtrace.$pid in the
56 static int sighandler_backtrace(void) {
57 char *tmpdir = getenv("TMPDIR");
61 pid_t pid_parent = getpid();
63 char *filename = NULL;
66 /* Find a unique filename for the backtrace (since the PID of i3 stays the
67 * same), so that we don’t overwrite earlier backtraces. */
70 sasprintf(&filename, "%s/i3-backtrace.%d.%d.txt", tmpdir, pid_parent, suffix);
72 } while (stat(filename, &bt) == 0);
74 pid_t pid_gdb = fork();
76 DLOG("Failed to fork for GDB\n");
78 } else if (pid_gdb == 0) {
83 if (pipe(stdin_pipe) == -1) {
84 ELOG("Failed to init stdin_pipe\n");
87 if (pipe(stdout_pipe) == -1) {
88 ELOG("Failed to init stdout_pipe\n");
92 /* close standard streams in case i3 is started from a terminal; gdb
93 * needs to run without controlling terminal for it to work properly in
99 /* We provide pipe file descriptors for stdin/stdout because gdb < 7.5
100 * crashes otherwise, see
101 * https://sourceware.org/bugzilla/show_bug.cgi?id=14114 */
102 dup2(stdin_pipe[0], STDIN_FILENO);
103 dup2(stdout_pipe[1], STDOUT_FILENO);
105 char *pid_s, *gdb_log_cmd;
106 sasprintf(&pid_s, "%d", pid_parent);
107 sasprintf(&gdb_log_cmd, "set logging file %s", filename);
117 "-ex", "set logging on",
121 execvp(args[0], args);
122 DLOG("Failed to exec GDB\n");
127 waitpid(pid_gdb, &status, 0);
129 /* see if the backtrace was successful or not */
130 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
131 DLOG("GDB did not run properly\n");
133 } else if (stat(filename, &bt) == -1) {
134 DLOG("GDB executed successfully, but no backtrace was generated\n");
140 static void sighandler_setup(void) {
141 border_width = logical_px(border_width);
142 margin = logical_px(margin);
145 message_intro = i3string_from_utf8("i3 has just crashed. Please report a bug for this.");
146 message_intro2 = i3string_from_utf8("To debug this problem, you can either attach gdb or choose from the following options:");
147 message_option_backtrace = i3string_from_utf8("- 'b' to save a backtrace (requires gdb)");
148 message_option_restart = i3string_from_utf8("- 'r' to restart i3 in-place");
149 message_option_forget = i3string_from_utf8("- 'f' to forget the previous layout and restart i3");
151 int width_longest_message = predict_text_width(message_intro2);
153 dialog_width = width_longest_message + 2 * border_width + 2 * margin;
154 dialog_height = num_lines * config.font.height + 2 * border_width + 2 * margin;
157 static void sighandler_create_dialogs(void) {
159 TAILQ_FOREACH(output, &outputs, outputs) {
160 if (!output->active) {
164 dialog_t *dialog = scalloc(1, sizeof(struct dialog_t));
165 TAILQ_INSERT_TAIL(&dialogs, dialog, dialogs);
167 xcb_visualid_t visual = get_visualid_by_depth(root_depth);
168 dialog->colormap = xcb_generate_id(conn);
169 xcb_create_colormap(conn, XCB_COLORMAP_ALLOC_NONE, dialog->colormap, root, visual);
175 /* Needs to be set in the case of a 32-bit root depth. */
176 mask |= XCB_CW_BACK_PIXEL;
177 values[i++] = root_screen->black_pixel;
179 /* Needs to be set in the case of a 32-bit root depth. */
180 mask |= XCB_CW_BORDER_PIXEL;
181 values[i++] = root_screen->black_pixel;
183 mask |= XCB_CW_OVERRIDE_REDIRECT;
186 /* Needs to be set in the case of a 32-bit root depth. */
187 mask |= XCB_CW_COLORMAP;
188 values[i++] = dialog->colormap;
190 dialog->dims.x = output->rect.x + (output->rect.width / 2);
191 dialog->dims.y = output->rect.y + (output->rect.height / 2);
192 dialog->dims.width = dialog_width;
193 dialog->dims.height = dialog_height;
195 /* Make sure the dialog is centered. */
196 dialog->dims.x -= dialog->dims.width / 2;
197 dialog->dims.y -= dialog->dims.height / 2;
199 dialog->id = create_window(conn, dialog->dims, root_depth, visual,
200 XCB_WINDOW_CLASS_INPUT_OUTPUT, XCURSOR_CURSOR_POINTER,
203 draw_util_surface_init(conn, &(dialog->surface), dialog->id, get_visualtype_by_id(visual),
204 dialog->dims.width, dialog->dims.height);
206 xcb_grab_keyboard(conn, false, dialog->id, XCB_CURRENT_TIME, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC);
208 /* Confine the pointer to the crash dialog. */
209 xcb_grab_pointer(conn, false, dialog->id, XCB_NONE, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC, dialog->id,
210 XCB_NONE, XCB_CURRENT_TIME);
213 sighandler_handle_expose();
217 static void sighandler_destroy_dialogs(void) {
218 while (!TAILQ_EMPTY(&dialogs)) {
219 dialog_t *dialog = TAILQ_FIRST(&dialogs);
221 xcb_free_colormap(conn, dialog->colormap);
222 draw_util_surface_free(conn, &(dialog->surface));
223 xcb_destroy_window(conn, dialog->id);
225 TAILQ_REMOVE(&dialogs, dialog, dialogs);
232 static void sighandler_handle_expose(void) {
234 TAILQ_FOREACH(current, &dialogs, dialogs) {
235 sighandler_draw_dialog(current);
241 static void sighandler_draw_dialog(dialog_t *dialog) {
242 const color_t black = draw_util_hex_to_color("#000000");
243 const color_t white = draw_util_hex_to_color("#FFFFFF");
244 const color_t red = draw_util_hex_to_color("#FF0000");
246 /* Start with a clean slate and draw a red border. */
247 draw_util_clear_surface(&(dialog->surface), red);
248 draw_util_rectangle(&(dialog->surface), black, border_width, border_width,
249 dialog->dims.width - 2 * border_width, dialog->dims.height - 2 * border_width);
251 int y = border_width + margin;
252 const int x = border_width + margin;
253 const int max_width = dialog->dims.width - 2 * x;
255 draw_util_text(message_intro, &(dialog->surface), white, black, x, y, max_width);
256 y += config.font.height;
258 draw_util_text(message_intro2, &(dialog->surface), white, black, x, y, max_width);
259 y += config.font.height;
261 char *bt_color = "#FFFFFF";
262 if (backtrace_done < 0) {
263 bt_color = "#AA0000";
264 } else if (backtrace_done > 0) {
265 bt_color = "#00AA00";
267 draw_util_text(message_option_backtrace, &(dialog->surface), draw_util_hex_to_color(bt_color), black, x, y, max_width);
268 y += config.font.height;
270 draw_util_text(message_option_restart, &(dialog->surface), white, black, x, y, max_width);
271 y += config.font.height;
273 draw_util_text(message_option_forget, &(dialog->surface), white, black, x, y, max_width);
274 y += config.font.height;
277 static void sighandler_handle_key_press(xcb_key_press_event_t *event) {
278 uint16_t state = event->state;
280 /* Apparently, after activating numlock once, the numlock modifier
281 * stays turned on (use xev(1) to verify). So, to resolve useful
282 * keysyms, we remove the numlock flag from the event state */
283 state &= ~xcb_numlock_mask;
285 xcb_keysym_t sym = xcb_key_press_lookup_keysym(keysyms, event, state);
288 DLOG("User issued core-dump command.\n");
290 /* fork and exec/attach GDB to the parent to get a backtrace in the
292 backtrace_done = sighandler_backtrace();
293 sighandler_handle_expose();
294 } else if (sym == 'r') {
295 sighandler_destroy_dialogs();
297 } else if (sym == 'f') {
298 sighandler_destroy_dialogs();
303 void handle_signal(int sig, siginfo_t *info, void *data) {
304 DLOG("i3 crashed. SIG: %d\n", sig);
306 struct sigaction action;
307 action.sa_handler = SIG_DFL;
309 sigemptyset(&action.sa_mask);
310 sigaction(sig, &action, NULL);
314 sighandler_create_dialogs();
316 xcb_generic_event_t *event;
317 /* Yay, more own eventhandlers… */
318 while ((event = xcb_wait_for_event(conn))) {
319 /* Strip off the highest bit (set if the event is generated) */
320 int type = (event->response_type & 0x7F);
323 sighandler_handle_key_press((xcb_key_press_event_t *)event);
326 if (((xcb_expose_event_t *)event)->count == 0) {
327 sighandler_handle_expose();
338 * Configured a signal handler to gracefully handle crashes and allow the user
339 * to generate a backtrace and rescue their session.
342 void setup_signal_handler(void) {
343 struct sigaction action;
345 action.sa_sigaction = handle_signal;
346 action.sa_flags = SA_NODEFER | SA_RESETHAND | SA_SIGINFO;
347 sigemptyset(&action.sa_mask);
349 /* Catch all signals with default action "Core", see signal(7) */
350 if (sigaction(SIGQUIT, &action, NULL) == -1 ||
351 sigaction(SIGILL, &action, NULL) == -1 ||
352 sigaction(SIGABRT, &action, NULL) == -1 ||
353 sigaction(SIGFPE, &action, NULL) == -1 ||
354 sigaction(SIGSEGV, &action, NULL) == -1)
355 ELOG("Could not setup signal handler.\n");