-#undef I3__FILE__
-#define I3__FILE__ "sighandler.c"
/*
* vim:ts=4:sw=4:expandtab
*
* i3 - an improved dynamic tiling window manager
- * © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
- * © 2009-2010 Jan-Erik Rediger
- *
- * sighandler.c: Interactive crash dialog upon SIGSEGV/SIGABRT/SIGFPE (offers
- * to restart inplace).
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
*
*/
#include "all.h"
#include <ev.h>
#include <iconv.h>
#include <signal.h>
+#include <sys/wait.h>
#include <xcb/xcb_event.h>
#include <X11/keysym.h>
-static xcb_gcontext_t pixmap_gc;
-static xcb_pixmap_t pixmap;
-static int raised_signal;
+typedef struct dialog_t {
+ xcb_window_t id;
+ xcb_colormap_t colormap;
+ Rect dims;
+ surface_t surface;
+
+ TAILQ_ENTRY(dialog_t)
+ dialogs;
+} dialog_t;
-static char *crash_text[] = {
- "i3 just crashed.",
- "To debug this problem, either attach gdb now",
- "or press",
- "- 'e' to exit and get a core-dump,",
- "- 'r' to restart i3 in-place or",
- "- 'f' to forget the current layout and restart"
-};
-static int crash_text_longest = 5;
+static TAILQ_HEAD(dialogs_head, dialog_t) dialogs = TAILQ_HEAD_INITIALIZER(dialogs);
+static int raised_signal;
+static int backtrace_done = 0;
+
+static int sighandler_backtrace(void);
+static void sighandler_setup(void);
+static void sighandler_create_dialogs(void);
+static void sighandler_destroy_dialogs(void);
+static void sighandler_handle_expose(void);
+static void sighandler_draw_dialog(dialog_t *dialog);
+static void sighandler_handle_key_press(xcb_key_press_event_t *event);
+
+static i3String *message_intro;
+static i3String *message_intro2;
+static i3String *message_option_backtrace;
+static i3String *message_option_restart;
+static i3String *message_option_forget;
+static int dialog_width;
+static int dialog_height;
+
+static int border_width = 2;
+static int margin = 4;
/*
- * Draw the window containing the info text
- *
+ * Attach gdb to pid_parent and dump a backtrace to i3-backtrace.$pid in the
+ * tmpdir
*/
-static int sig_draw_window(xcb_window_t win, int width, int height, int font_height, i3String **crash_text_i3strings) {
- /* re-draw the background */
- xcb_rectangle_t border = { 0, 0, width, height},
- inner = { 2, 2, width - 4, height - 4};
- xcb_change_gc(conn, pixmap_gc, XCB_GC_FOREGROUND, (uint32_t[]){ get_colorpixel("#FF0000") });
- xcb_poly_fill_rectangle(conn, pixmap, pixmap_gc, 1, &border);
- xcb_change_gc(conn, pixmap_gc, XCB_GC_FOREGROUND, (uint32_t[]){ get_colorpixel("#000000") });
- xcb_poly_fill_rectangle(conn, pixmap, pixmap_gc, 1, &inner);
-
- /* restore font color */
- set_font_colors(pixmap_gc, get_colorpixel("#FFFFFF"), get_colorpixel("#000000"));
-
- for (int i = 0; crash_text_i3strings[i] != NULL; ++i) {
- draw_text((char *)i3string_as_ucs2(crash_text_i3strings[i]), i3string_get_num_glyphs(crash_text_i3strings[i]), true, pixmap, pixmap_gc,
- 8, 5 + i * font_height, width - 16);
+static int sighandler_backtrace(void) {
+ char *tmpdir = getenv("TMPDIR");
+ if (tmpdir == NULL)
+ tmpdir = "/tmp";
+
+ pid_t pid_parent = getpid();
+
+ char *filename = NULL;
+ int suffix = 0;
+ /* Find a unique filename for the backtrace (since the PID of i3 stays the
+ * same), so that we don’t overwrite earlier backtraces. */
+ do {
+ FREE(filename);
+ sasprintf(&filename, "%s/i3-backtrace.%d.%d.txt", tmpdir, pid_parent, suffix);
+ suffix++;
+ } while (path_exists(filename));
+
+ pid_t pid_gdb = fork();
+ if (pid_gdb < 0) {
+ DLOG("Failed to fork for GDB\n");
+ return -1;
+ } else if (pid_gdb == 0) {
+ /* child */
+ int stdin_pipe[2],
+ stdout_pipe[2];
+
+ if (pipe(stdin_pipe) == -1) {
+ ELOG("Failed to init stdin_pipe\n");
+ return -1;
+ }
+ if (pipe(stdout_pipe) == -1) {
+ ELOG("Failed to init stdout_pipe\n");
+ return -1;
+ }
+
+ /* close standard streams in case i3 is started from a terminal; gdb
+ * needs to run without controlling terminal for it to work properly in
+ * this situation */
+ close(STDIN_FILENO);
+ close(STDOUT_FILENO);
+ close(STDERR_FILENO);
+
+ /* We provide pipe file descriptors for stdin/stdout because gdb < 7.5
+ * crashes otherwise, see
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=14114 */
+ dup2(stdin_pipe[0], STDIN_FILENO);
+ dup2(stdout_pipe[1], STDOUT_FILENO);
+
+ char *pid_s, *gdb_log_cmd;
+ sasprintf(&pid_s, "%d", pid_parent);
+ sasprintf(&gdb_log_cmd, "set logging file %s", filename);
+
+ char *args[] = {
+ "gdb",
+ start_argv[0],
+ "-p",
+ pid_s,
+ "-batch",
+ "-nx",
+ "-ex", gdb_log_cmd,
+ "-ex", "set logging on",
+ "-ex", "bt full",
+ "-ex", "quit",
+ NULL};
+ execvp(args[0], args);
+ DLOG("Failed to exec GDB\n");
+ exit(1);
}
+ int status = 0;
- /* Copy the contents of the pixmap to the real window */
- xcb_copy_area(conn, pixmap, win, pixmap_gc, 0, 0, 0, 0, width, height);
- xcb_flush(conn);
+ waitpid(pid_gdb, &status, 0);
+ /* see if the backtrace was successful or not */
+ if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
+ DLOG("GDB did not run properly\n");
+ return -1;
+ } else if (!path_exists(filename)) {
+ DLOG("GDB executed successfully, but no backtrace was generated\n");
+ return -1;
+ }
return 1;
}
-/*
- * Handles keypresses of 'e' or 'r' to exit or restart i3
- *
- */
-static int sig_handle_key_press(void *ignored, xcb_connection_t *conn, xcb_key_press_event_t *event) {
- uint16_t state = event->state;
+static void sighandler_setup(void) {
+ border_width = logical_px(border_width);
+ margin = logical_px(margin);
- /* Apparantly, after activating numlock once, the numlock modifier
- * stays turned on (use xev(1) to verify). So, to resolve useful
- * keysyms, we remove the numlock flag from the event state */
- state &= ~xcb_numlock_mask;
+ int num_lines = 5;
+ message_intro = i3string_from_utf8("i3 has just crashed. Please report a bug for this.");
+ message_intro2 = i3string_from_utf8("To debug this problem, you can either attach gdb or choose from the following options:");
+ message_option_backtrace = i3string_from_utf8("- 'b' to save a backtrace (requires gdb)");
+ message_option_restart = i3string_from_utf8("- 'r' to restart i3 in-place");
+ message_option_forget = i3string_from_utf8("- 'f' to forget the previous layout and restart i3");
- xcb_keysym_t sym = xcb_key_press_lookup_keysym(keysyms, event, state);
+ int width_longest_message = predict_text_width(message_intro2);
- if (sym == 'e') {
- DLOG("User issued exit-command, raising error again.\n");
- raise(raised_signal);
- exit(1);
- }
+ dialog_width = width_longest_message + 2 * border_width + 2 * margin;
+ dialog_height = num_lines * config.font.height + 2 * border_width + 2 * margin;
+}
- if (sym == 'r')
- i3_restart(false);
+static void sighandler_create_dialogs(void) {
+ Output *output;
+ TAILQ_FOREACH(output, &outputs, outputs) {
+ if (!output->active) {
+ continue;
+ }
- if (sym == 'f')
- i3_restart(true);
+ dialog_t *dialog = scalloc(1, sizeof(struct dialog_t));
+ TAILQ_INSERT_TAIL(&dialogs, dialog, dialogs);
- return 1;
-}
+ xcb_visualid_t visual = get_visualid_by_depth(root_depth);
+ dialog->colormap = xcb_generate_id(conn);
+ xcb_create_colormap(conn, XCB_COLORMAP_ALLOC_NONE, dialog->colormap, root, visual);
-/*
- * Opens the window we use for input/output and maps it
- *
- */
-static xcb_window_t open_input_window(xcb_connection_t *conn, Rect screen_rect, uint32_t width, uint32_t height) {
- xcb_window_t win = xcb_generate_id(conn);
+ uint32_t mask = 0;
+ uint32_t values[4];
+ int i = 0;
- uint32_t mask = 0;
- uint32_t values[2];
+ /* Needs to be set in the case of a 32-bit root depth. */
+ mask |= XCB_CW_BACK_PIXEL;
+ values[i++] = root_screen->black_pixel;
- mask |= XCB_CW_BACK_PIXEL;
- values[0] = 0;
+ /* Needs to be set in the case of a 32-bit root depth. */
+ mask |= XCB_CW_BORDER_PIXEL;
+ values[i++] = root_screen->black_pixel;
- mask |= XCB_CW_OVERRIDE_REDIRECT;
- values[1] = 1;
+ mask |= XCB_CW_OVERRIDE_REDIRECT;
+ values[i++] = 1;
- /* center each popup on the specified screen */
- uint32_t x = screen_rect.x + ((screen_rect.width / 2) - (width / 2)),
- y = screen_rect.y + ((screen_rect.height / 2) - (height / 2));
+ /* Needs to be set in the case of a 32-bit root depth. */
+ mask |= XCB_CW_COLORMAP;
+ values[i++] = dialog->colormap;
- xcb_create_window(conn,
- XCB_COPY_FROM_PARENT,
- win, /* the window id */
- root, /* parent == root */
- x, y, width, height, /* dimensions */
- 0, /* border = 0, we draw our own */
- XCB_WINDOW_CLASS_INPUT_OUTPUT,
- XCB_WINDOW_CLASS_COPY_FROM_PARENT, /* copy visual from parent */
- mask,
- values);
+ dialog->dims.x = output->rect.x + (output->rect.width / 2);
+ dialog->dims.y = output->rect.y + (output->rect.height / 2);
+ dialog->dims.width = dialog_width;
+ dialog->dims.height = dialog_height;
- /* Map the window (= make it visible) */
- xcb_map_window(conn, win);
+ /* Make sure the dialog is centered. */
+ dialog->dims.x -= dialog->dims.width / 2;
+ dialog->dims.y -= dialog->dims.height / 2;
- return win;
+ dialog->id = create_window(conn, dialog->dims, root_depth, visual,
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, XCURSOR_CURSOR_POINTER,
+ true, mask, values);
+
+ draw_util_surface_init(conn, &(dialog->surface), dialog->id, get_visualtype_by_id(visual),
+ dialog->dims.width, dialog->dims.height);
+
+ xcb_grab_keyboard(conn, false, dialog->id, XCB_CURRENT_TIME, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC);
+
+ /* Confine the pointer to the crash dialog. */
+ xcb_grab_pointer(conn, false, dialog->id, XCB_NONE, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC, dialog->id,
+ XCB_NONE, XCB_CURRENT_TIME);
+ }
+
+ sighandler_handle_expose();
+ xcb_flush(conn);
}
-/*
- * Handle signals
- * It creates a window asking the user to restart in-place
- * or exit to generate a core dump
- *
- */
-void handle_signal(int sig, siginfo_t *info, void *data) {
- DLOG("i3 crashed. SIG: %d\n", sig);
+static void sighandler_destroy_dialogs(void) {
+ while (!TAILQ_EMPTY(&dialogs)) {
+ dialog_t *dialog = TAILQ_FIRST(&dialogs);
- struct sigaction action;
- action.sa_handler = SIG_DFL;
- sigaction(sig, &action, NULL);
- raised_signal = sig;
+ xcb_free_colormap(conn, dialog->colormap);
+ draw_util_surface_free(conn, &(dialog->surface));
+ xcb_destroy_window(conn, dialog->id);
- /* width and height of the popup window, so that the text fits in */
- int crash_text_num = sizeof(crash_text) / sizeof(char*);
- int height = 13 + (crash_text_num * config.font.height);
+ TAILQ_REMOVE(&dialogs, dialog, dialogs);
+ free(dialog);
+ }
- int crash_text_length = sizeof(crash_text) / sizeof(char*);
- i3String **crash_text_i3strings = smalloc(sizeof(i3String *) * (crash_text_length + 1));
- /* Pre-compute i3Strings for our text */
- for (int i = 0; i < crash_text_length; ++i) {
- crash_text_i3strings[i] = i3string_from_utf8(crash_text[i]);
+ xcb_flush(conn);
+}
+
+static void sighandler_handle_expose(void) {
+ dialog_t *current;
+ TAILQ_FOREACH(current, &dialogs, dialogs) {
+ sighandler_draw_dialog(current);
}
- crash_text_i3strings[crash_text_length] = NULL;
- /* calculate width for longest text */
- int font_width = predict_text_width((char *)i3string_as_ucs2(crash_text_i3strings[crash_text_longest]), i3string_get_num_glyphs(crash_text_i3strings[crash_text_longest]), true);
- int width = font_width + 20;
-
- /* Open a popup window on each virtual screen */
- Output *screen;
- xcb_window_t win;
- TAILQ_FOREACH(screen, &outputs, outputs) {
- if (!screen->active)
- continue;
- win = open_input_window(conn, screen->rect, width, height);
- /* Create pixmap */
- pixmap = xcb_generate_id(conn);
- pixmap_gc = xcb_generate_id(conn);
- xcb_create_pixmap(conn, root_depth, pixmap, win, width, height);
- xcb_create_gc(conn, pixmap_gc, pixmap, 0, 0);
+ xcb_flush(conn);
+}
- /* Grab the keyboard to get all input */
- xcb_grab_keyboard(conn, false, win, XCB_CURRENT_TIME, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC);
+static void sighandler_draw_dialog(dialog_t *dialog) {
+ const color_t black = draw_util_hex_to_color("#000000");
+ const color_t white = draw_util_hex_to_color("#FFFFFF");
+ const color_t red = draw_util_hex_to_color("#FF0000");
- /* Grab the cursor inside the popup */
- xcb_grab_pointer(conn, false, win, XCB_NONE, XCB_GRAB_MODE_ASYNC,
- XCB_GRAB_MODE_ASYNC, win, XCB_NONE, XCB_CURRENT_TIME);
+ /* Start with a clean slate and draw a red border. */
+ draw_util_clear_surface(&(dialog->surface), red);
+ draw_util_rectangle(&(dialog->surface), black, border_width, border_width,
+ dialog->dims.width - 2 * border_width, dialog->dims.height - 2 * border_width);
- sig_draw_window(win, width, height, config.font.height, crash_text_i3strings);
- xcb_flush(conn);
+ int y = border_width + margin;
+ const int x = border_width + margin;
+ const int max_width = dialog->dims.width - 2 * x;
+
+ draw_util_text(message_intro, &(dialog->surface), white, black, x, y, max_width);
+ y += config.font.height;
+
+ draw_util_text(message_intro2, &(dialog->surface), white, black, x, y, max_width);
+ y += config.font.height;
+
+ char *bt_color = "#FFFFFF";
+ if (backtrace_done < 0) {
+ bt_color = "#AA0000";
+ } else if (backtrace_done > 0) {
+ bt_color = "#00AA00";
}
+ draw_util_text(message_option_backtrace, &(dialog->surface), draw_util_hex_to_color(bt_color), black, x, y, max_width);
+ y += config.font.height;
+
+ draw_util_text(message_option_restart, &(dialog->surface), white, black, x, y, max_width);
+ y += config.font.height;
+
+ draw_util_text(message_option_forget, &(dialog->surface), white, black, x, y, max_width);
+ y += config.font.height;
+}
+
+static void sighandler_handle_key_press(xcb_key_press_event_t *event) {
+ uint16_t state = event->state;
+
+ /* Apparently, after activating numlock once, the numlock modifier
+ * stays turned on (use xev(1) to verify). So, to resolve useful
+ * keysyms, we remove the numlock flag from the event state */
+ state &= ~xcb_numlock_mask;
+
+ xcb_keysym_t sym = xcb_key_press_lookup_keysym(keysyms, event, state);
+
+ if (sym == 'b') {
+ DLOG("User issued core-dump command.\n");
+
+ /* fork and exec/attach GDB to the parent to get a backtrace in the
+ * tmpdir */
+ backtrace_done = sighandler_backtrace();
+ sighandler_handle_expose();
+ } else if (sym == 'r') {
+ sighandler_destroy_dialogs();
+ i3_restart(false);
+ } else if (sym == 'f') {
+ sighandler_destroy_dialogs();
+ i3_restart(true);
+ }
+}
+
+static void handle_signal(int sig, siginfo_t *info, void *data) {
+ DLOG("i3 crashed. SIG: %d\n", sig);
+
+ struct sigaction action;
+ action.sa_handler = SIG_DFL;
+ action.sa_flags = 0;
+ sigemptyset(&action.sa_mask);
+ sigaction(sig, &action, NULL);
+ raised_signal = sig;
+
+ sighandler_setup();
+ sighandler_create_dialogs();
xcb_generic_event_t *event;
/* Yay, more own eventhandlers… */
while ((event = xcb_wait_for_event(conn))) {
/* Strip off the highest bit (set if the event is generated) */
int type = (event->response_type & 0x7F);
- if (type == XCB_KEY_PRESS) {
- sig_handle_key_press(NULL, conn, (xcb_key_press_event_t*)event);
+ switch (type) {
+ case XCB_KEY_PRESS:
+ sighandler_handle_key_press((xcb_key_press_event_t *)event);
+ break;
+ case XCB_EXPOSE:
+ if (((xcb_expose_event_t *)event)->count == 0) {
+ sighandler_handle_expose();
+ }
+
+ break;
}
+
free(event);
}
}
/*
- * Setup signal handlers to safely handle SIGSEGV and SIGFPE
+ * Configured a signal handler to gracefully handle crashes and allow the user
+ * to generate a backtrace and rescue their session.
*
*/
void setup_signal_handler(void) {
sigaction(SIGABRT, &action, NULL) == -1 ||
sigaction(SIGFPE, &action, NULL) == -1 ||
sigaction(SIGSEGV, &action, NULL) == -1)
- ELOG("Could not setup signal handler");
+ ELOG("Could not setup signal handler.\n");
}
projects / i3 / i3 / blobdiff