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 * 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>
20 #include <yajl/yajl_version.h>
24 char *current_socketpath = NULL;
26 /* Shorter names for all those yajl_gen_* functions */
27 #define y(x, ...) yajl_gen_ ## x (gen, ##__VA_ARGS__)
28 #define ystr(str) yajl_gen_string(gen, (unsigned char*)str, strlen(str))
30 TAILQ_HEAD(ipc_client_head, ipc_client) all_clients = TAILQ_HEAD_INITIALIZER(all_clients);
33 * Puts the given socket file descriptor into non-blocking mode or dies if
34 * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
35 * IPC model because we should by no means block the window manager.
38 static void set_nonblock(int sockfd) {
39 int flags = fcntl(sockfd, F_GETFL, 0);
41 if (fcntl(sockfd, F_SETFL, flags) < 0)
42 err(-1, "Could not set O_NONBLOCK");
46 * Emulates mkdir -p (creates any missing folders)
49 static bool mkdirp(const char *path) {
50 if (mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) == 0)
52 if (errno != ENOENT) {
53 ELOG("mkdir(%s) failed: %s\n", path, strerror(errno));
56 char *copy = strdup(path);
57 /* strip trailing slashes, if any */
58 while (copy[strlen(copy)-1] == '/')
59 copy[strlen(copy)-1] = '\0';
61 char *sep = strrchr(copy, '/');
67 result = mkdirp(path);
73 static void ipc_send_message(int fd, const unsigned char *payload,
74 int message_type, int message_size) {
75 int buffer_size = strlen("i3-ipc") + sizeof(uint32_t) +
76 sizeof(uint32_t) + message_size;
77 char msg[buffer_size];
80 strcpy(walk, "i3-ipc");
81 walk += strlen("i3-ipc");
82 memcpy(walk, &message_size, sizeof(uint32_t));
83 walk += sizeof(uint32_t);
84 memcpy(walk, &message_type, sizeof(uint32_t));
85 walk += sizeof(uint32_t);
86 memcpy(walk, payload, message_size);
89 int bytes_to_go = buffer_size;
90 while (sent_bytes < bytes_to_go) {
91 int n = write(fd, msg + sent_bytes, bytes_to_go);
93 DLOG("write() failed: %s\n", strerror(errno));
103 * Sends the specified event to all IPC clients which are currently connected
104 * and subscribed to this kind of event.
107 void ipc_send_event(const char *event, uint32_t message_type, const char *payload) {
109 TAILQ_FOREACH(current, &all_clients, clients) {
110 /* see if this client is interested in this event */
111 bool interested = false;
112 for (int i = 0; i < current->num_events; i++) {
113 if (strcasecmp(current->events[i], event) != 0)
121 ipc_send_message(current->fd, (const unsigned char*)payload,
122 message_type, strlen(payload));
127 * Calls shutdown() on each socket and closes it. This function to be called
128 * when exiting or restarting only!
131 void ipc_shutdown() {
133 TAILQ_FOREACH(current, &all_clients, clients) {
134 shutdown(current->fd, SHUT_RDWR);
140 * Executes the command and returns whether it could be successfully parsed
141 * or not (at the moment, always returns true).
144 IPC_HANDLER(command) {
145 /* To get a properly terminated buffer, we copy
146 * message_size bytes out of the buffer */
147 char *command = scalloc(message_size + 1);
148 strncpy(command, (const char*)message, message_size);
149 LOG("IPC: received: *%s*\n", command);
150 const char *reply = parse_cmd((const char*)command);
154 /* If no reply was provided, we just use the default success message */
156 reply = "{\"success\":true}";
157 ipc_send_message(fd, (const unsigned char*)reply,
158 I3_IPC_REPLY_TYPE_COMMAND, strlen(reply));
161 static void dump_rect(yajl_gen gen, const char *name, Rect r) {
171 y(integer, r.height);
175 void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
178 y(integer, (long int)con);
181 y(integer, con->type);
184 switch (con->orientation) {
197 y(double, con->percent);
200 y(integer, con->urgent);
203 y(integer, (con == focused));
206 y(integer, con->layout);
209 y(integer, con->border_style);
211 dump_rect(gen, "rect", con->rect);
212 dump_rect(gen, "window_rect", con->window_rect);
213 dump_rect(gen, "geometry", con->geometry);
218 if (con->type == CT_WORKSPACE) {
220 y(integer, con->num);
225 y(integer, con->window->id);
231 if (con->type != CT_DOCKAREA || !inplace_restart) {
232 TAILQ_FOREACH(node, &(con->nodes_head), nodes) {
233 dump_node(gen, node, inplace_restart);
238 ystr("floating_nodes");
240 TAILQ_FOREACH(node, &(con->floating_head), floating_windows) {
241 dump_node(gen, node, inplace_restart);
247 TAILQ_FOREACH(node, &(con->focus_head), nodes) {
248 y(integer, (long int)node);
252 ystr("fullscreen_mode");
253 y(integer, con->fullscreen_mode);
258 TAILQ_FOREACH(match, &(con->swallow_head), matches) {
259 if (match->dock != -1) {
262 y(integer, match->dock);
263 ystr("insert_where");
264 y(integer, match->insert_where);
268 /* TODO: the other swallow keys */
271 if (inplace_restart) {
272 if (con->window != NULL) {
275 y(integer, con->window->id);
285 setlocale(LC_NUMERIC, "C");
287 yajl_gen gen = yajl_gen_alloc(NULL);
289 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
291 dump_node(gen, croot, false);
292 setlocale(LC_NUMERIC, "");
294 const unsigned char *payload;
300 y(get_buf, &payload, &length);
302 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_TREE, length);
307 * Formats the reply message for a GET_WORKSPACES request and sends it to the
311 IPC_HANDLER(get_workspaces) {
313 yajl_gen gen = yajl_gen_alloc(NULL);
315 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
319 Con *focused_ws = con_get_workspace(focused);
322 TAILQ_FOREACH(output, &(croot->nodes_head), nodes) {
324 TAILQ_FOREACH(ws, &(output_get_content(output)->nodes_head), nodes) {
325 assert(ws->type == CT_WORKSPACE);
331 else y(integer, ws->num);
337 y(bool, workspace_is_visible(ws));
340 y(bool, ws == focused_ws);
345 y(integer, ws->rect.x);
347 y(integer, ws->rect.y);
349 y(integer, ws->rect.width);
351 y(integer, ws->rect.height);
366 const unsigned char *payload;
372 y(get_buf, &payload, &length);
374 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_WORKSPACES, length);
379 * Formats the reply message for a GET_OUTPUTS request and sends it to the
383 IPC_HANDLER(get_outputs) {
385 yajl_gen gen = yajl_gen_alloc(NULL);
387 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
392 TAILQ_FOREACH(output, &outputs, outputs) {
399 y(bool, output->active);
404 y(integer, output->rect.x);
406 y(integer, output->rect.y);
408 y(integer, output->rect.width);
410 y(integer, output->rect.height);
413 ystr("current_workspace");
415 if (output->con && (ws = con_get_fullscreen_con(output->con)))
424 const unsigned char *payload;
430 y(get_buf, &payload, &length);
432 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_OUTPUTS, length);
437 * Callback for the YAJL parser (will be called when a string is parsed).
441 static int add_subscription(void *extra, const unsigned char *s,
444 static int add_subscription(void *extra, const unsigned char *s,
447 ipc_client *client = extra;
449 DLOG("should add subscription to extra %p, sub %.*s\n", client, len, s);
450 int event = client->num_events;
452 client->num_events++;
453 client->events = realloc(client->events, client->num_events * sizeof(char*));
454 /* We copy the string because it is not null-terminated and strndup()
455 * is missing on some BSD systems */
456 client->events[event] = scalloc(len+1);
457 memcpy(client->events[event], s, len);
459 DLOG("client is now subscribed to:\n");
460 for (int i = 0; i < client->num_events; i++)
461 DLOG("event %s\n", client->events[i]);
468 * Subscribes this connection to the event types which were given as a JSON
469 * serialized array in the payload field of the message.
472 IPC_HANDLER(subscribe) {
474 yajl_callbacks callbacks;
476 ipc_client *current, *client = NULL;
478 /* Search the ipc_client structure for this connection */
479 TAILQ_FOREACH(current, &all_clients, clients) {
480 if (current->fd != fd)
487 if (client == NULL) {
488 ELOG("Could not find ipc_client data structure for fd %d\n", fd);
492 /* Setup the JSON parser */
493 memset(&callbacks, 0, sizeof(yajl_callbacks));
494 callbacks.yajl_string = add_subscription;
497 p = yajl_alloc(&callbacks, NULL, (void*)client);
499 p = yajl_alloc(&callbacks, NULL, NULL, (void*)client);
501 stat = yajl_parse(p, (const unsigned char*)message, message_size);
502 if (stat != yajl_status_ok) {
504 err = yajl_get_error(p, true, (const unsigned char*)message,
506 ELOG("YAJL parse error: %s\n", err);
507 yajl_free_error(p, err);
509 const char *reply = "{\"success\":false}";
510 ipc_send_message(fd, (const unsigned char*)reply,
511 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
516 const char *reply = "{\"success\":true}";
517 ipc_send_message(fd, (const unsigned char*)reply,
518 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
521 /* The index of each callback function corresponds to the numeric
522 * value of the message type (see include/i3/ipc.h) */
523 handler_t handlers[5] = {
525 handle_get_workspaces,
532 * Handler for activity on a client connection, receives a message from a
535 * For now, the maximum message size is 2048. I’m not sure for what the
536 * IPC interface will be used in the future, thus I’m not implementing a
537 * mechanism for arbitrarily long messages, as it seems like overkill
541 static void ipc_receive_message(EV_P_ struct ev_io *w, int revents) {
543 int n = read(w->fd, buf, sizeof(buf));
545 /* On error or an empty message, we close the connection */
548 /* FIXME: I get these when closing a client socket,
549 * therefore we just treat them as an error. Is this
551 if (errno == EAGAIN || errno == EWOULDBLOCK)
555 /* If not, there was some kind of error. We don’t bother
556 * and close the connection */
559 /* Delete the client from the list of clients */
561 TAILQ_FOREACH(current, &all_clients, clients) {
562 if (current->fd != w->fd)
565 for (int i = 0; i < current->num_events; i++)
566 free(current->events[i]);
567 /* We can call TAILQ_REMOVE because we break out of the
568 * TAILQ_FOREACH afterwards */
569 TAILQ_REMOVE(&all_clients, current, clients);
575 DLOG("IPC: client disconnected\n");
579 /* Terminate the message correctly */
582 /* Check if the message starts with the i3 IPC magic code */
583 if (n < strlen(I3_IPC_MAGIC)) {
584 DLOG("IPC: message too short, ignoring\n");
588 if (strncmp(buf, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
589 DLOG("IPC: message does not start with the IPC magic\n");
593 uint8_t *message = (uint8_t*)buf;
595 DLOG("IPC: n = %d\n", n);
596 message += strlen(I3_IPC_MAGIC);
597 n -= strlen(I3_IPC_MAGIC);
599 /* The next 32 bit after the magic are the message size */
600 uint32_t message_size;
601 memcpy(&message_size, (uint32_t*)message, sizeof(uint32_t));
602 message += sizeof(uint32_t);
603 n -= sizeof(uint32_t);
605 if (message_size > n) {
606 DLOG("IPC: Either the message size was wrong or the message was not read completely, dropping\n");
610 /* The last 32 bits of the header are the message type */
611 uint32_t message_type;
612 memcpy(&message_type, (uint32_t*)message, sizeof(uint32_t));
613 message += sizeof(uint32_t);
614 n -= sizeof(uint32_t);
616 if (message_type >= (sizeof(handlers) / sizeof(handler_t)))
617 DLOG("Unhandled message type: %d\n", message_type);
619 handler_t h = handlers[message_type];
620 h(w->fd, message, n, message_size, message_type);
623 message += message_size;
628 * Handler for activity on the listening socket, meaning that a new client
629 * has just connected and we should accept() him. Sets up the event handler
630 * for activity on the new connection and inserts the file descriptor into
631 * the list of clients.
634 void ipc_new_client(EV_P_ struct ev_io *w, int revents) {
635 struct sockaddr_un peer;
636 socklen_t len = sizeof(struct sockaddr_un);
638 if ((client = accept(w->fd, (struct sockaddr*)&peer, &len)) < 0) {
641 else perror("accept()");
645 set_nonblock(client);
647 struct ev_io *package = scalloc(sizeof(struct ev_io));
648 ev_io_init(package, ipc_receive_message, client, EV_READ);
649 ev_io_start(EV_A_ package);
651 DLOG("IPC: new client connected\n");
653 ipc_client *new = scalloc(sizeof(ipc_client));
656 TAILQ_INSERT_TAIL(&all_clients, new, clients);
660 * Creates the UNIX domain socket at the given path, sets it to non-blocking
661 * mode, bind()s and listen()s on it.
664 int ipc_create_socket(const char *filename) {
667 FREE(current_socketpath);
669 char *resolved = resolve_tilde(filename);
670 DLOG("Creating IPC-socket at %s\n", resolved);
671 char *copy = sstrdup(resolved);
672 const char *dir = dirname(copy);
673 if (!path_exists(dir))
677 /* Unlink the unix domain socket before */
680 if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
686 (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
688 struct sockaddr_un addr;
689 memset(&addr, 0, sizeof(struct sockaddr_un));
690 addr.sun_family = AF_LOCAL;
691 strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
692 if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_un)) < 0) {
698 set_nonblock(sockfd);
700 if (listen(sockfd, 5) < 0) {
706 current_socketpath = resolved;