2 * vim:ts=4:sw=4:expandtab
4 * i3 - an improved dynamic tiling window manager
6 * © 2009-2011 Michael Stapelberg and contributors
8 * See file LICENSE for license information.
10 * util.c: Utility functions, which can be useful everywhere.
16 #if defined(__OpenBSD__)
17 #include <sys/cdefs.h>
21 #include <yajl/yajl_version.h>
26 static iconv_t conversion_descriptor = 0;
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 * The s* functions (safe) are wrappers around malloc, strdup, …, which exits if one of
63 * the called functions returns NULL, meaning that there is no more memory available
66 void *smalloc(size_t size) {
67 void *result = malloc(size);
68 exit_if_null(result, "Error: out of memory (malloc(%zd))\n", size);
72 void *scalloc(size_t size) {
73 void *result = calloc(size, 1);
74 exit_if_null(result, "Error: out of memory (calloc(%zd))\n", size);
78 void *srealloc(void *ptr, size_t size) {
79 void *result = realloc(ptr, size);
80 if (result == NULL && size > 0)
81 die("Error: out memory (realloc(%zd))\n", size);
85 char *sstrdup(const char *str) {
86 char *result = strdup(str);
87 exit_if_null(result, "Error: out of memory (strdup())\n");
92 * Starts the given application by passing it through a shell. We use double fork
93 * to avoid zombie processes. As the started application’s parent exits (immediately),
94 * the application is reparented to init (process-id 1), which correctly handles
95 * childs, so we don’t have to do it :-).
97 * The shell is determined by looking for the SHELL environment variable. If it
98 * does not exist, /bin/sh is used.
101 void start_application(const char *command) {
102 LOG("executing: %s\n", command);
107 /* Stores the path of the shell */
108 static const char *shell = NULL;
111 if ((shell = getenv("SHELL")) == NULL)
114 /* This is the child */
115 execl(shell, shell, "-c", command, (void*)NULL);
124 * exec()s an i3 utility, for example the config file migration script or
125 * i3-nagbar. This function first searches $PATH for the given utility named,
126 * then falls back to the dirname() of the i3 executable path and then falls
127 * back to the dirname() of the target of /proc/self/exe (on linux).
129 * This function should be called after fork()ing.
131 * The first argument of the given argv vector will be overwritten with the
132 * executable name, so pass NULL.
134 * If the utility cannot be found in any of these locations, it exits with
138 void exec_i3_utility(char *name, char *argv[]) {
139 /* start the migration script, search PATH first */
140 char *migratepath = name;
141 argv[0] = migratepath;
142 execvp(migratepath, argv);
144 /* if the script is not in path, maybe the user installed to a strange
145 * location and runs the i3 binary with an absolute path. We use
146 * argv[0]’s dirname */
147 char *pathbuf = strdup(start_argv[0]);
148 char *dir = dirname(pathbuf);
149 asprintf(&migratepath, "%s/%s", dir, name);
150 argv[0] = migratepath;
151 execvp(migratepath, argv);
153 #if defined(__linux__)
154 /* on linux, we have one more fall-back: dirname(/proc/self/exe) */
156 if (readlink("/proc/self/exe", buffer, BUFSIZ) == -1) {
157 warn("could not read /proc/self/exe");
160 dir = dirname(buffer);
161 asprintf(&migratepath, "%s/%s", dir, name);
162 argv[0] = migratepath;
163 execvp(migratepath, argv);
166 warn("Could not start %s", name);
171 * Checks a generic cookie for errors and quits with the given message if there
175 void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie, char *err_message) {
176 xcb_generic_error_t *error = xcb_request_check(conn, cookie);
178 fprintf(stderr, "ERROR: %s (X error %d)\n", err_message , error->error_code);
179 xcb_disconnect(conn);
185 * Converts the given string to UCS-2 big endian for use with
186 * xcb_image_text_16(). The amount of real glyphs is stored in real_strlen,
187 * a buffer containing the UCS-2 encoded string (16 bit per glyph) is
188 * returned. It has to be freed when done.
191 char *convert_utf8_to_ucs2(char *input, int *real_strlen) {
192 size_t input_size = strlen(input) + 1;
193 /* UCS-2 consumes exactly two bytes for each glyph */
194 int buffer_size = input_size * 2;
196 char *buffer = smalloc(buffer_size);
197 size_t output_size = buffer_size;
198 /* We need to use an additional pointer, because iconv() modifies it */
199 char *output = buffer;
201 /* We convert the input into UCS-2 big endian */
202 if (conversion_descriptor == 0) {
203 conversion_descriptor = iconv_open("UCS-2BE", "UTF-8");
204 if (conversion_descriptor == 0) {
205 fprintf(stderr, "error opening the conversion context\n");
210 /* Get the conversion descriptor back to original state */
211 iconv(conversion_descriptor, NULL, NULL, NULL, NULL);
213 /* Convert our text */
214 int rc = iconv(conversion_descriptor, (void*)&input, &input_size, &output, &output_size);
215 if (rc == (size_t)-1) {
216 perror("Converting to UCS-2 failed");
217 if (real_strlen != NULL)
222 if (real_strlen != NULL)
223 *real_strlen = ((buffer_size - output_size) / 2) - 1;
229 * This function resolves ~ in pathnames.
230 * It may resolve wildcards in the first part of the path, but if no match
231 * or multiple matches are found, it just returns a copy of path as given.
234 char *resolve_tilde(const char *path) {
235 static glob_t globbuf;
236 char *head, *tail, *result;
238 tail = strchr(path, '/');
239 head = strndup(path, tail ? tail - path : strlen(path));
241 int res = glob(head, GLOB_TILDE, NULL, &globbuf);
243 /* no match, or many wildcard matches are bad */
244 if (res == GLOB_NOMATCH || globbuf.gl_pathc != 1)
245 result = sstrdup(path);
247 die("glob() failed");
249 head = globbuf.gl_pathv[0];
250 result = scalloc(strlen(head) + (tail ? strlen(tail) : 0) + 1);
251 strncpy(result, head, strlen(head));
253 strncat(result, tail, strlen(tail));
261 * Checks if the given path exists by calling stat().
264 bool path_exists(const char *path) {
266 return (stat(path, &buf) == 0);
270 * Goes through the list of arguments (for exec()) and checks if the given argument
271 * is present. If not, it copies the arguments (because we cannot realloc it) and
272 * appends the given argument.
275 static char **append_argument(char **original, char *argument) {
277 for (num_args = 0; original[num_args] != NULL; num_args++) {
278 DLOG("original argument: \"%s\"\n", original[num_args]);
279 /* If the argument is already present we return the original pointer */
280 if (strcmp(original[num_args], argument) == 0)
283 /* Copy the original array */
284 char **result = smalloc((num_args+2) * sizeof(char*));
285 memcpy(result, original, num_args * sizeof(char*));
286 result[num_args] = argument;
287 result[num_args+1] = NULL;
293 * Returns the name of a temporary file with the specified prefix.
296 char *get_process_filename(const char *prefix) {
297 char *dir = getenv("XDG_RUNTIME_DIR");
299 struct passwd *pw = getpwuid(getuid());
300 const char *username = pw ? pw->pw_name : "unknown";
301 if (asprintf(&dir, "/tmp/i3-%s", username) == -1) {
302 perror("asprintf()");
307 if (asprintf(&tmp, "%s/i3", dir) == -1) {
308 perror("asprintf()");
313 if (!path_exists(dir)) {
314 if (mkdir(dir, 0700) == -1) {
320 if (asprintf(&filename, "%s/%s.%d", dir, prefix, getpid()) == -1) {
321 perror("asprintf()");
329 #define y(x, ...) yajl_gen_ ## x (gen, ##__VA_ARGS__)
330 #define ystr(str) yajl_gen_string(gen, (unsigned char*)str, strlen(str))
332 char *store_restart_layout() {
333 setlocale(LC_NUMERIC, "C");
335 yajl_gen gen = yajl_gen_alloc(NULL);
337 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
340 dump_node(gen, croot, true);
342 setlocale(LC_NUMERIC, "");
344 const unsigned char *payload;
350 y(get_buf, &payload, &length);
352 /* create a temporary file if one hasn't been specified, or just
353 * resolve the tildes in the specified path */
355 if (config.restart_state_path == NULL) {
356 filename = get_process_filename("restart-state");
360 filename = resolve_tilde(config.restart_state_path);
363 int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
371 while (written < length) {
372 int n = write(fd, payload + written, length - written);
373 /* TODO: correct error-handling */
381 printf("write == 0?\n");
388 printf("written: %d of %zd\n", written, length);
390 printf("written: %d of %d\n", written, length);
396 printf("layout: %.*s\n", (int)length, payload);
405 * Restart i3 in-place
406 * appends -a to argument list to disable autostart
409 void i3_restart(bool forget_layout) {
410 char *restart_filename = forget_layout ? NULL : store_restart_layout();
412 kill_configerror_nagbar(true);
418 LOG("restarting \"%s\"...\n", start_argv[0]);
419 /* make sure -a is in the argument list or append it */
420 start_argv = append_argument(start_argv, "-a");
422 /* replace -r <file> so that the layout is restored */
423 if (restart_filename != NULL) {
424 /* create the new argv */
426 for (num_args = 0; start_argv[num_args] != NULL; num_args++);
427 char **new_argv = scalloc((num_args + 3) * sizeof(char*));
429 /* copy the arguments, but skip the ones we'll replace */
431 bool skip_next = false;
432 for (int i = 0; i < num_args; ++i) {
435 else if (!strcmp(start_argv[i], "-r") ||
436 !strcmp(start_argv[i], "--restart"))
439 new_argv[write_index++] = start_argv[i];
442 /* add the arguments we'll replace */
443 new_argv[write_index++] = "--restart";
444 new_argv[write_index] = restart_filename;
447 start_argv = new_argv;
450 execvp(start_argv[0], start_argv);
454 #if defined(__OpenBSD__) || defined(__APPLE__)
458 * Find the first occurrence of the byte string s in byte string l.
461 void *memmem(const void *l, size_t l_len, const void *s, size_t s_len) {
462 register char *cur, *last;
463 const char *cl = (const char *)l;
464 const char *cs = (const char *)s;
466 /* we need something to compare */
467 if (l_len == 0 || s_len == 0)
470 /* "s" must be smaller or equal to "l" */
474 /* special case where s_len == 1 */
476 return memchr(l, (int)*cs, l_len);
478 /* the last position where its possible to find "s" in "l" */
479 last = (char *)cl + l_len - s_len;
481 for (cur = (char *)cl; cur <= last; cur++)
482 if (cur[0] == cs[0] && memcmp(cur, cs, s_len) == 0)
490 #if defined(__APPLE__)
494 * Returns a pointer to a new string which is a duplicate of the
495 * string, but only copies at most n characters.
498 char *strndup(const char *str, size_t n) {
502 for (len = 0; len < n && str[len]; len++)
505 if ((copy = malloc(len + 1)) == NULL)
507 memcpy(copy, str, len);