2 #define I3__FILE__ "util.c"
4 * vim:ts=4:sw=4:expandtab
6 * i3 - an improved dynamic tiling window manager
7 * © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
9 * util.c: Utility functions, which can be useful everywhere within i3 (see
17 #if defined(__OpenBSD__)
18 #include <sys/cdefs.h>
22 #include <yajl/yajl_version.h>
25 #define SN_API_NOT_YET_FROZEN 1
26 #include <libsn/sn-launcher.h>
28 int min(int a, int b) {
29 return (a < b ? a : b);
32 int max(int a, int b) {
33 return (a > b ? a : b);
36 bool rect_contains(Rect rect, uint32_t x, uint32_t y) {
37 return (x >= rect.x &&
38 x <= (rect.x + rect.width) &&
40 y <= (rect.y + rect.height));
43 Rect rect_add(Rect a, Rect b) {
44 return (Rect){a.x + b.x,
51 * Updates *destination with new_value and returns true if it was changed or false
55 bool update_if_necessary(uint32_t *destination, const uint32_t new_value) {
56 uint32_t old_value = *destination;
58 return ((*destination = new_value) != old_value);
62 * exec()s an i3 utility, for example the config file migration script or
63 * i3-nagbar. This function first searches $PATH for the given utility named,
64 * then falls back to the dirname() of the i3 executable path and then falls
65 * back to the dirname() of the target of /proc/self/exe (on linux).
67 * This function should be called after fork()ing.
69 * The first argument of the given argv vector will be overwritten with the
70 * executable name, so pass NULL.
72 * If the utility cannot be found in any of these locations, it exits with
76 void exec_i3_utility(char *name, char *argv[]) {
77 /* start the migration script, search PATH first */
78 char *migratepath = name;
79 argv[0] = migratepath;
80 execvp(migratepath, argv);
82 /* if the script is not in path, maybe the user installed to a strange
83 * location and runs the i3 binary with an absolute path. We use
84 * argv[0]’s dirname */
85 char *pathbuf = strdup(start_argv[0]);
86 char *dir = dirname(pathbuf);
87 sasprintf(&migratepath, "%s/%s", dir, name);
88 argv[0] = migratepath;
89 execvp(migratepath, argv);
91 #if defined(__linux__)
92 /* on linux, we have one more fall-back: dirname(/proc/self/exe) */
94 if (readlink("/proc/self/exe", buffer, BUFSIZ) == -1) {
95 warn("could not read /proc/self/exe");
98 dir = dirname(buffer);
99 sasprintf(&migratepath, "%s/%s", dir, name);
100 argv[0] = migratepath;
101 execvp(migratepath, argv);
104 warn("Could not start %s", name);
109 * Checks a generic cookie for errors and quits with the given message if there
113 void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie, char *err_message) {
114 xcb_generic_error_t *error = xcb_request_check(conn, cookie);
116 fprintf(stderr, "ERROR: %s (X error %d)\n", err_message , error->error_code);
117 xcb_disconnect(conn);
123 * This function resolves ~ in pathnames.
124 * It may resolve wildcards in the first part of the path, but if no match
125 * or multiple matches are found, it just returns a copy of path as given.
128 char *resolve_tilde(const char *path) {
129 static glob_t globbuf;
130 char *head, *tail, *result;
132 tail = strchr(path, '/');
133 head = strndup(path, tail ? (size_t)(tail - path) : strlen(path));
135 int res = glob(head, GLOB_TILDE, NULL, &globbuf);
137 /* no match, or many wildcard matches are bad */
138 if (res == GLOB_NOMATCH || globbuf.gl_pathc != 1)
139 result = sstrdup(path);
141 die("glob() failed");
143 head = globbuf.gl_pathv[0];
144 result = scalloc(strlen(head) + (tail ? strlen(tail) : 0) + 1);
145 strncpy(result, head, strlen(head));
147 strncat(result, tail, strlen(tail));
155 * Checks if the given path exists by calling stat().
158 bool path_exists(const char *path) {
160 return (stat(path, &buf) == 0);
164 * Goes through the list of arguments (for exec()) and checks if the given argument
165 * is present. If not, it copies the arguments (because we cannot realloc it) and
166 * appends the given argument.
169 static char **append_argument(char **original, char *argument) {
171 for (num_args = 0; original[num_args] != NULL; num_args++) {
172 DLOG("original argument: \"%s\"\n", original[num_args]);
173 /* If the argument is already present we return the original pointer */
174 if (strcmp(original[num_args], argument) == 0)
177 /* Copy the original array */
178 char **result = smalloc((num_args+2) * sizeof(char*));
179 memcpy(result, original, num_args * sizeof(char*));
180 result[num_args] = argument;
181 result[num_args+1] = NULL;
186 #define y(x, ...) yajl_gen_ ## x (gen, ##__VA_ARGS__)
187 #define ystr(str) yajl_gen_string(gen, (unsigned char*)str, strlen(str))
189 char *store_restart_layout(void) {
190 setlocale(LC_NUMERIC, "C");
192 yajl_gen gen = yajl_gen_alloc(NULL);
194 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
197 dump_node(gen, croot, true);
199 setlocale(LC_NUMERIC, "");
201 const unsigned char *payload;
207 y(get_buf, &payload, &length);
209 /* create a temporary file if one hasn't been specified, or just
210 * resolve the tildes in the specified path */
212 if (config.restart_state_path == NULL) {
213 filename = get_process_filename("restart-state");
217 filename = resolve_tilde(config.restart_state_path);
220 int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
228 while (written < length) {
229 int n = write(fd, payload + written, length - written);
230 /* TODO: correct error-handling */
238 printf("write == 0?\n");
245 DLOG("written: %zd of %zd\n", written, length);
247 DLOG("written: %d of %d\n", written, length);
253 printf("layout: %.*s\n", (int)length, payload);
262 * Restart i3 in-place
263 * appends -a to argument list to disable autostart
266 void i3_restart(bool forget_layout) {
267 char *restart_filename = forget_layout ? NULL : store_restart_layout();
269 kill_nagbar(&config_error_nagbar_pid, true);
270 kill_nagbar(&command_error_nagbar_pid, true);
276 LOG("restarting \"%s\"...\n", start_argv[0]);
277 /* make sure -a is in the argument list or append it */
278 start_argv = append_argument(start_argv, "-a");
280 /* replace -r <file> so that the layout is restored */
281 if (restart_filename != NULL) {
282 /* create the new argv */
284 for (num_args = 0; start_argv[num_args] != NULL; num_args++);
285 char **new_argv = scalloc((num_args + 3) * sizeof(char*));
287 /* copy the arguments, but skip the ones we'll replace */
289 bool skip_next = false;
290 for (int i = 0; i < num_args; ++i) {
293 else if (!strcmp(start_argv[i], "-r") ||
294 !strcmp(start_argv[i], "--restart"))
297 new_argv[write_index++] = start_argv[i];
300 /* add the arguments we'll replace */
301 new_argv[write_index++] = "--restart";
302 new_argv[write_index] = restart_filename;
305 start_argv = new_argv;
308 execvp(start_argv[0], start_argv);
312 #if defined(__OpenBSD__) || defined(__APPLE__)
316 * Find the first occurrence of the byte string s in byte string l.
319 void *memmem(const void *l, size_t l_len, const void *s, size_t s_len) {
320 register char *cur, *last;
321 const char *cl = (const char *)l;
322 const char *cs = (const char *)s;
324 /* we need something to compare */
325 if (l_len == 0 || s_len == 0)
328 /* "s" must be smaller or equal to "l" */
332 /* special case where s_len == 1 */
334 return memchr(l, (int)*cs, l_len);
336 /* the last position where its possible to find "s" in "l" */
337 last = (char *)cl + l_len - s_len;
339 for (cur = (char *)cl; cur <= last; cur++)
340 if (cur[0] == cs[0] && memcmp(cur, cs, s_len) == 0)
349 * Handler which will be called when we get a SIGCHLD for the nagbar, meaning
350 * it exited (or could not be started, depending on the exit code).
353 static void nagbar_exited(EV_P_ ev_child *watcher, int revents) {
354 ev_child_stop(EV_A_ watcher);
356 if (!WIFEXITED(watcher->rstatus)) {
357 ELOG("ERROR: i3-nagbar did not exit normally.\n");
361 int exitcode = WEXITSTATUS(watcher->rstatus);
362 DLOG("i3-nagbar process exited with status %d\n", exitcode);
364 ELOG("ERROR: i3-nagbar could not be found. Is it correctly installed on your system?\n");
367 *((pid_t*)watcher->data) = -1;
371 * Cleanup handler. Will be called when i3 exits. Kills i3-nagbar with signal
372 * SIGKILL (9) to make sure there are no left-over i3-nagbar processes.
375 static void nagbar_cleanup(EV_P_ ev_cleanup *watcher, int revent) {
376 pid_t *nagbar_pid = (pid_t*)watcher->data;
377 if (*nagbar_pid != -1) {
378 LOG("Sending SIGKILL (%d) to i3-nagbar with PID %d\n", SIGKILL, *nagbar_pid);
379 kill(*nagbar_pid, SIGKILL);
384 * Starts an i3-nagbar instance with the given parameters. Takes care of
385 * handling SIGCHLD and killing i3-nagbar when i3 exits.
387 * The resulting PID will be stored in *nagbar_pid and can be used with
388 * kill_nagbar() to kill the bar later on.
391 void start_nagbar(pid_t *nagbar_pid, char *argv[]) {
392 if (*nagbar_pid != -1) {
393 DLOG("i3-nagbar already running (PID %d), not starting again.\n", *nagbar_pid);
397 *nagbar_pid = fork();
398 if (*nagbar_pid == -1) {
399 warn("Could not fork()");
404 if (*nagbar_pid == 0)
405 exec_i3_utility("i3-nagbar", argv);
407 DLOG("Starting i3-nagbar with PID %d\n", *nagbar_pid);
410 /* install a child watcher */
411 ev_child *child = smalloc(sizeof(ev_child));
412 ev_child_init(child, &nagbar_exited, *nagbar_pid, 0);
413 child->data = nagbar_pid;
414 ev_child_start(main_loop, child);
416 /* install a cleanup watcher (will be called when i3 exits and i3-nagbar is
418 ev_cleanup *cleanup = smalloc(sizeof(ev_cleanup));
419 ev_cleanup_init(cleanup, nagbar_cleanup);
420 cleanup->data = nagbar_pid;
421 ev_cleanup_start(main_loop, cleanup);
425 * Kills the i3-nagbar process, if *nagbar_pid != -1.
427 * If wait_for_it is set (restarting i3), this function will waitpid(),
428 * otherwise, ev is assumed to handle it (reloading).
431 void kill_nagbar(pid_t *nagbar_pid, bool wait_for_it) {
432 if (*nagbar_pid == -1)
435 if (kill(*nagbar_pid, SIGTERM) == -1)
436 warn("kill(configerror_nagbar) failed");
441 /* When restarting, we don’t enter the ev main loop anymore and after the
442 * exec(), our old pid is no longer watched. So, ev won’t handle SIGCHLD
443 * for us and we would end up with a <defunct> process. Therefore we
445 waitpid(*nagbar_pid, NULL, 0);