2 * vim:ts=4:sw=4:expandtab
4 * i3 - an improved dynamic tiling window manager
6 * © 2009-2010 Michael Stapelberg and contributors
8 * See file LICENSE for license information.
10 * ipc.c: Everything about the UNIX domain sockets for IPC
13 #include <sys/socket.h>
18 #include <yajl/yajl_gen.h>
19 #include <yajl/yajl_parse.h>
23 char *current_socketpath = NULL;
25 /* Shorter names for all those yajl_gen_* functions */
26 #define y(x, ...) yajl_gen_ ## x (gen, ##__VA_ARGS__)
27 #define ystr(str) yajl_gen_string(gen, (unsigned char*)str, strlen(str))
29 TAILQ_HEAD(ipc_client_head, ipc_client) all_clients = TAILQ_HEAD_INITIALIZER(all_clients);
32 * Puts the given socket file descriptor into non-blocking mode or dies if
33 * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
34 * IPC model because we should by no means block the window manager.
37 static void set_nonblock(int sockfd) {
38 int flags = fcntl(sockfd, F_GETFL, 0);
40 if (fcntl(sockfd, F_SETFL, flags) < 0)
41 err(-1, "Could not set O_NONBLOCK");
45 * Emulates mkdir -p (creates any missing folders)
48 static bool mkdirp(const char *path) {
49 if (mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) == 0)
51 if (errno != ENOENT) {
52 ELOG("mkdir(%s) failed: %s\n", path, strerror(errno));
55 char *copy = strdup(path);
56 /* strip trailing slashes, if any */
57 while (copy[strlen(copy)-1] == '/')
58 copy[strlen(copy)-1] = '\0';
60 char *sep = strrchr(copy, '/');
66 result = mkdirp(path);
72 static void ipc_send_message(int fd, const unsigned char *payload,
73 int message_type, int message_size) {
74 int buffer_size = strlen("i3-ipc") + sizeof(uint32_t) +
75 sizeof(uint32_t) + message_size;
76 char msg[buffer_size];
79 strcpy(walk, "i3-ipc");
80 walk += strlen("i3-ipc");
81 memcpy(walk, &message_size, sizeof(uint32_t));
82 walk += sizeof(uint32_t);
83 memcpy(walk, &message_type, sizeof(uint32_t));
84 walk += sizeof(uint32_t);
85 memcpy(walk, payload, message_size);
88 int bytes_to_go = buffer_size;
89 while (sent_bytes < bytes_to_go) {
90 int n = write(fd, msg + sent_bytes, bytes_to_go);
92 DLOG("write() failed: %s\n", strerror(errno));
102 * Sends the specified event to all IPC clients which are currently connected
103 * and subscribed to this kind of event.
106 void ipc_send_event(const char *event, uint32_t message_type, const char *payload) {
108 TAILQ_FOREACH(current, &all_clients, clients) {
109 /* see if this client is interested in this event */
110 bool interested = false;
111 for (int i = 0; i < current->num_events; i++) {
112 if (strcasecmp(current->events[i], event) != 0)
120 ipc_send_message(current->fd, (const unsigned char*)payload,
121 message_type, strlen(payload));
126 * Calls shutdown() on each socket and closes it. This function to be called
127 * when exiting or restarting only!
130 void ipc_shutdown() {
132 TAILQ_FOREACH(current, &all_clients, clients) {
133 shutdown(current->fd, SHUT_RDWR);
139 * Executes the command and returns whether it could be successfully parsed
140 * or not (at the moment, always returns true).
143 IPC_HANDLER(command) {
144 /* To get a properly terminated buffer, we copy
145 * message_size bytes out of the buffer */
146 char *command = scalloc(message_size + 1);
147 strncpy(command, (const char*)message, message_size);
148 LOG("IPC: received: *%s*\n", command);
149 const char *reply = parse_cmd((const char*)command);
153 /* If no reply was provided, we just use the default success message */
155 reply = "{\"success\":true}";
156 ipc_send_message(fd, (const unsigned char*)reply,
157 I3_IPC_REPLY_TYPE_COMMAND, strlen(reply));
160 static void dump_rect(yajl_gen gen, const char *name, Rect r) {
170 y(integer, r.height);
174 void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
177 y(integer, (long int)con);
180 y(integer, con->type);
183 switch (con->orientation) {
196 y(double, con->percent);
199 y(integer, con->urgent);
202 y(integer, (con == focused));
205 y(integer, con->layout);
208 y(integer, con->border_style);
210 dump_rect(gen, "rect", con->rect);
211 dump_rect(gen, "window_rect", con->window_rect);
212 dump_rect(gen, "geometry", con->geometry);
217 if (con->type == CT_WORKSPACE) {
219 y(integer, con->num);
224 y(integer, con->window->id);
230 if (con->type != CT_DOCKAREA || !inplace_restart) {
231 TAILQ_FOREACH(node, &(con->nodes_head), nodes) {
232 dump_node(gen, node, inplace_restart);
237 ystr("floating_nodes");
239 TAILQ_FOREACH(node, &(con->floating_head), floating_windows) {
240 dump_node(gen, node, inplace_restart);
246 TAILQ_FOREACH(node, &(con->focus_head), nodes) {
247 y(integer, (long int)node);
251 ystr("fullscreen_mode");
252 y(integer, con->fullscreen_mode);
257 TAILQ_FOREACH(match, &(con->swallow_head), matches) {
258 if (match->dock != -1) {
261 y(integer, match->dock);
262 ystr("insert_where");
263 y(integer, match->insert_where);
267 /* TODO: the other swallow keys */
270 if (inplace_restart) {
271 if (con->window != NULL) {
274 y(integer, con->window->id);
284 setlocale(LC_NUMERIC, "C");
285 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
286 dump_node(gen, croot, false);
287 setlocale(LC_NUMERIC, "");
289 const unsigned char *payload;
291 y(get_buf, &payload, &length);
293 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_TREE, length);
298 * Formats the reply message for a GET_WORKSPACES request and sends it to the
302 IPC_HANDLER(get_workspaces) {
303 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
306 Con *focused_ws = con_get_workspace(focused);
309 TAILQ_FOREACH(output, &(croot->nodes_head), nodes) {
311 TAILQ_FOREACH(ws, &(output_get_content(output)->nodes_head), nodes) {
312 assert(ws->type == CT_WORKSPACE);
318 else y(integer, ws->num);
324 y(bool, workspace_is_visible(ws));
327 y(bool, ws == focused_ws);
332 y(integer, ws->rect.x);
334 y(integer, ws->rect.y);
336 y(integer, ws->rect.width);
338 y(integer, ws->rect.height);
353 const unsigned char *payload;
355 y(get_buf, &payload, &length);
357 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_WORKSPACES, length);
362 * Formats the reply message for a GET_OUTPUTS request and sends it to the
366 IPC_HANDLER(get_outputs) {
367 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
371 TAILQ_FOREACH(output, &outputs, outputs) {
378 y(bool, output->active);
383 y(integer, output->rect.x);
385 y(integer, output->rect.y);
387 y(integer, output->rect.width);
389 y(integer, output->rect.height);
392 ystr("current_workspace");
394 if (output->con && (ws = con_get_fullscreen_con(output->con)))
403 const unsigned char *payload;
405 y(get_buf, &payload, &length);
407 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_OUTPUTS, length);
412 * Callback for the YAJL parser (will be called when a string is parsed).
415 static int add_subscription(void *extra, const unsigned char *s,
417 ipc_client *client = extra;
419 DLOG("should add subscription to extra %p, sub %.*s\n", client, len, s);
420 int event = client->num_events;
422 client->num_events++;
423 client->events = realloc(client->events, client->num_events * sizeof(char*));
424 /* We copy the string because it is not null-terminated and strndup()
425 * is missing on some BSD systems */
426 client->events[event] = scalloc(len+1);
427 memcpy(client->events[event], s, len);
429 DLOG("client is now subscribed to:\n");
430 for (int i = 0; i < client->num_events; i++)
431 DLOG("event %s\n", client->events[i]);
438 * Subscribes this connection to the event types which were given as a JSON
439 * serialized array in the payload field of the message.
442 IPC_HANDLER(subscribe) {
444 yajl_callbacks callbacks;
446 ipc_client *current, *client = NULL;
448 /* Search the ipc_client structure for this connection */
449 TAILQ_FOREACH(current, &all_clients, clients) {
450 if (current->fd != fd)
457 if (client == NULL) {
458 ELOG("Could not find ipc_client data structure for fd %d\n", fd);
462 /* Setup the JSON parser */
463 memset(&callbacks, 0, sizeof(yajl_callbacks));
464 callbacks.yajl_string = add_subscription;
466 p = yajl_alloc(&callbacks, NULL, NULL, (void*)client);
467 stat = yajl_parse(p, (const unsigned char*)message, message_size);
468 if (stat != yajl_status_ok) {
470 err = yajl_get_error(p, true, (const unsigned char*)message,
472 ELOG("YAJL parse error: %s\n", err);
473 yajl_free_error(p, err);
475 const char *reply = "{\"success\":false}";
476 ipc_send_message(fd, (const unsigned char*)reply,
477 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
482 const char *reply = "{\"success\":true}";
483 ipc_send_message(fd, (const unsigned char*)reply,
484 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
487 /* The index of each callback function corresponds to the numeric
488 * value of the message type (see include/i3/ipc.h) */
489 handler_t handlers[5] = {
491 handle_get_workspaces,
498 * Handler for activity on a client connection, receives a message from a
501 * For now, the maximum message size is 2048. I’m not sure for what the
502 * IPC interface will be used in the future, thus I’m not implementing a
503 * mechanism for arbitrarily long messages, as it seems like overkill
507 static void ipc_receive_message(EV_P_ struct ev_io *w, int revents) {
509 int n = read(w->fd, buf, sizeof(buf));
511 /* On error or an empty message, we close the connection */
514 /* FIXME: I get these when closing a client socket,
515 * therefore we just treat them as an error. Is this
517 if (errno == EAGAIN || errno == EWOULDBLOCK)
521 /* If not, there was some kind of error. We don’t bother
522 * and close the connection */
525 /* Delete the client from the list of clients */
527 TAILQ_FOREACH(current, &all_clients, clients) {
528 if (current->fd != w->fd)
531 for (int i = 0; i < current->num_events; i++)
532 free(current->events[i]);
533 /* We can call TAILQ_REMOVE because we break out of the
534 * TAILQ_FOREACH afterwards */
535 TAILQ_REMOVE(&all_clients, current, clients);
541 DLOG("IPC: client disconnected\n");
545 /* Terminate the message correctly */
548 /* Check if the message starts with the i3 IPC magic code */
549 if (n < strlen(I3_IPC_MAGIC)) {
550 DLOG("IPC: message too short, ignoring\n");
554 if (strncmp(buf, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
555 DLOG("IPC: message does not start with the IPC magic\n");
559 uint8_t *message = (uint8_t*)buf;
561 DLOG("IPC: n = %d\n", n);
562 message += strlen(I3_IPC_MAGIC);
563 n -= strlen(I3_IPC_MAGIC);
565 /* The next 32 bit after the magic are the message size */
566 uint32_t message_size = *((uint32_t*)message);
567 message += sizeof(uint32_t);
568 n -= sizeof(uint32_t);
570 if (message_size > n) {
571 DLOG("IPC: Either the message size was wrong or the message was not read completely, dropping\n");
575 /* The last 32 bits of the header are the message type */
576 uint32_t message_type = *((uint32_t*)message);
577 message += sizeof(uint32_t);
578 n -= sizeof(uint32_t);
580 if (message_type >= (sizeof(handlers) / sizeof(handler_t)))
581 DLOG("Unhandled message type: %d\n", message_type);
583 handler_t h = handlers[message_type];
584 h(w->fd, message, n, message_size, message_type);
587 message += message_size;
592 * Handler for activity on the listening socket, meaning that a new client
593 * has just connected and we should accept() him. Sets up the event handler
594 * for activity on the new connection and inserts the file descriptor into
595 * the list of clients.
598 void ipc_new_client(EV_P_ struct ev_io *w, int revents) {
599 struct sockaddr_un peer;
600 socklen_t len = sizeof(struct sockaddr_un);
602 if ((client = accept(w->fd, (struct sockaddr*)&peer, &len)) < 0) {
605 else perror("accept()");
609 set_nonblock(client);
611 struct ev_io *package = scalloc(sizeof(struct ev_io));
612 ev_io_init(package, ipc_receive_message, client, EV_READ);
613 ev_io_start(EV_A_ package);
615 DLOG("IPC: new client connected\n");
617 ipc_client *new = scalloc(sizeof(ipc_client));
620 TAILQ_INSERT_TAIL(&all_clients, new, clients);
624 * Creates the UNIX domain socket at the given path, sets it to non-blocking
625 * mode, bind()s and listen()s on it.
628 int ipc_create_socket(const char *filename) {
631 FREE(current_socketpath);
633 char *resolved = resolve_tilde(filename);
634 DLOG("Creating IPC-socket at %s\n", resolved);
635 char *copy = sstrdup(resolved);
636 const char *dir = dirname(copy);
637 if (!path_exists(dir))
641 /* Unlink the unix domain socket before */
644 if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
650 (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
652 struct sockaddr_un addr;
653 memset(&addr, 0, sizeof(struct sockaddr_un));
654 addr.sun_family = AF_LOCAL;
655 strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
656 if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_un)) < 0) {
662 set_nonblock(sockfd);
664 if (listen(sockfd, 5) < 0) {
670 current_socketpath = resolved;