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 strncpy(walk, "i3-ipc", buffer_size - 1);
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);
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 if (con->percent == 0.0)
198 else y(double, con->percent);
201 y(bool, con->urgent);
204 y(bool, (con == focused));
207 switch (con->layout) {
226 switch (con->border_style) {
238 dump_rect(gen, "rect", con->rect);
239 dump_rect(gen, "window_rect", con->window_rect);
240 dump_rect(gen, "geometry", con->geometry);
245 if (con->type == CT_WORKSPACE) {
247 y(integer, con->num);
252 y(integer, con->window->id);
258 if (con->type != CT_DOCKAREA || !inplace_restart) {
259 TAILQ_FOREACH(node, &(con->nodes_head), nodes) {
260 dump_node(gen, node, inplace_restart);
265 ystr("floating_nodes");
267 TAILQ_FOREACH(node, &(con->floating_head), floating_windows) {
268 dump_node(gen, node, inplace_restart);
274 TAILQ_FOREACH(node, &(con->focus_head), nodes) {
275 y(integer, (long int)node);
279 ystr("fullscreen_mode");
280 y(integer, con->fullscreen_mode);
285 TAILQ_FOREACH(match, &(con->swallow_head), matches) {
286 if (match->dock != -1) {
289 y(integer, match->dock);
290 ystr("insert_where");
291 y(integer, match->insert_where);
295 /* TODO: the other swallow keys */
298 if (inplace_restart) {
299 if (con->window != NULL) {
302 y(integer, con->window->id);
312 setlocale(LC_NUMERIC, "C");
314 yajl_gen gen = yajl_gen_alloc(NULL);
316 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
318 dump_node(gen, croot, false);
319 setlocale(LC_NUMERIC, "");
321 const unsigned char *payload;
327 y(get_buf, &payload, &length);
329 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_TREE, length);
334 * Formats the reply message for a GET_WORKSPACES request and sends it to the
338 IPC_HANDLER(get_workspaces) {
340 yajl_gen gen = yajl_gen_alloc(NULL);
342 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
346 Con *focused_ws = con_get_workspace(focused);
349 TAILQ_FOREACH(output, &(croot->nodes_head), nodes) {
351 TAILQ_FOREACH(ws, &(output_get_content(output)->nodes_head), nodes) {
352 assert(ws->type == CT_WORKSPACE);
358 else y(integer, ws->num);
364 y(bool, workspace_is_visible(ws));
367 y(bool, ws == focused_ws);
372 y(integer, ws->rect.x);
374 y(integer, ws->rect.y);
376 y(integer, ws->rect.width);
378 y(integer, ws->rect.height);
393 const unsigned char *payload;
399 y(get_buf, &payload, &length);
401 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_WORKSPACES, length);
406 * Formats the reply message for a GET_OUTPUTS request and sends it to the
410 IPC_HANDLER(get_outputs) {
412 yajl_gen gen = yajl_gen_alloc(NULL);
414 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
419 TAILQ_FOREACH(output, &outputs, outputs) {
426 y(bool, output->active);
431 y(integer, output->rect.x);
433 y(integer, output->rect.y);
435 y(integer, output->rect.width);
437 y(integer, output->rect.height);
440 ystr("current_workspace");
442 if (output->con && (ws = con_get_fullscreen_con(output->con, CF_OUTPUT)))
451 const unsigned char *payload;
457 y(get_buf, &payload, &length);
459 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_OUTPUTS, length);
464 * Callback for the YAJL parser (will be called when a string is parsed).
468 static int add_subscription(void *extra, const unsigned char *s,
471 static int add_subscription(void *extra, const unsigned char *s,
474 ipc_client *client = extra;
476 DLOG("should add subscription to extra %p, sub %.*s\n", client, len, s);
477 int event = client->num_events;
479 client->num_events++;
480 client->events = realloc(client->events, client->num_events * sizeof(char*));
481 /* We copy the string because it is not null-terminated and strndup()
482 * is missing on some BSD systems */
483 client->events[event] = scalloc(len+1);
484 memcpy(client->events[event], s, len);
486 DLOG("client is now subscribed to:\n");
487 for (int i = 0; i < client->num_events; i++)
488 DLOG("event %s\n", client->events[i]);
495 * Subscribes this connection to the event types which were given as a JSON
496 * serialized array in the payload field of the message.
499 IPC_HANDLER(subscribe) {
501 yajl_callbacks callbacks;
503 ipc_client *current, *client = NULL;
505 /* Search the ipc_client structure for this connection */
506 TAILQ_FOREACH(current, &all_clients, clients) {
507 if (current->fd != fd)
514 if (client == NULL) {
515 ELOG("Could not find ipc_client data structure for fd %d\n", fd);
519 /* Setup the JSON parser */
520 memset(&callbacks, 0, sizeof(yajl_callbacks));
521 callbacks.yajl_string = add_subscription;
524 p = yajl_alloc(&callbacks, NULL, (void*)client);
526 p = yajl_alloc(&callbacks, NULL, NULL, (void*)client);
528 stat = yajl_parse(p, (const unsigned char*)message, message_size);
529 if (stat != yajl_status_ok) {
531 err = yajl_get_error(p, true, (const unsigned char*)message,
533 ELOG("YAJL parse error: %s\n", err);
534 yajl_free_error(p, err);
536 const char *reply = "{\"success\":false}";
537 ipc_send_message(fd, (const unsigned char*)reply,
538 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
543 const char *reply = "{\"success\":true}";
544 ipc_send_message(fd, (const unsigned char*)reply,
545 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
548 /* The index of each callback function corresponds to the numeric
549 * value of the message type (see include/i3/ipc.h) */
550 handler_t handlers[5] = {
552 handle_get_workspaces,
559 * Handler for activity on a client connection, receives a message from a
562 * For now, the maximum message size is 2048. I’m not sure for what the
563 * IPC interface will be used in the future, thus I’m not implementing a
564 * mechanism for arbitrarily long messages, as it seems like overkill
568 static void ipc_receive_message(EV_P_ struct ev_io *w, int revents) {
570 int n = read(w->fd, buf, sizeof(buf));
572 /* On error or an empty message, we close the connection */
575 /* FIXME: I get these when closing a client socket,
576 * therefore we just treat them as an error. Is this
578 if (errno == EAGAIN || errno == EWOULDBLOCK)
582 /* If not, there was some kind of error. We don’t bother
583 * and close the connection */
586 /* Delete the client from the list of clients */
588 TAILQ_FOREACH(current, &all_clients, clients) {
589 if (current->fd != w->fd)
592 for (int i = 0; i < current->num_events; i++)
593 free(current->events[i]);
594 /* We can call TAILQ_REMOVE because we break out of the
595 * TAILQ_FOREACH afterwards */
596 TAILQ_REMOVE(&all_clients, current, clients);
602 DLOG("IPC: client disconnected\n");
606 /* Terminate the message correctly */
609 /* Check if the message starts with the i3 IPC magic code */
610 if (n < strlen(I3_IPC_MAGIC)) {
611 DLOG("IPC: message too short, ignoring\n");
615 if (strncmp(buf, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
616 DLOG("IPC: message does not start with the IPC magic\n");
620 uint8_t *message = (uint8_t*)buf;
622 DLOG("IPC: n = %d\n", n);
623 message += strlen(I3_IPC_MAGIC);
624 n -= strlen(I3_IPC_MAGIC);
626 /* The next 32 bit after the magic are the message size */
627 uint32_t message_size;
628 memcpy(&message_size, (uint32_t*)message, sizeof(uint32_t));
629 message += sizeof(uint32_t);
630 n -= sizeof(uint32_t);
632 if (message_size > n) {
633 DLOG("IPC: Either the message size was wrong or the message was not read completely, dropping\n");
637 /* The last 32 bits of the header are the message type */
638 uint32_t message_type;
639 memcpy(&message_type, (uint32_t*)message, sizeof(uint32_t));
640 message += sizeof(uint32_t);
641 n -= sizeof(uint32_t);
643 if (message_type >= (sizeof(handlers) / sizeof(handler_t)))
644 DLOG("Unhandled message type: %d\n", message_type);
646 handler_t h = handlers[message_type];
647 h(w->fd, message, n, message_size, message_type);
650 message += message_size;
655 * Handler for activity on the listening socket, meaning that a new client
656 * has just connected and we should accept() him. Sets up the event handler
657 * for activity on the new connection and inserts the file descriptor into
658 * the list of clients.
661 void ipc_new_client(EV_P_ struct ev_io *w, int revents) {
662 struct sockaddr_un peer;
663 socklen_t len = sizeof(struct sockaddr_un);
665 if ((client = accept(w->fd, (struct sockaddr*)&peer, &len)) < 0) {
668 else perror("accept()");
672 set_nonblock(client);
674 struct ev_io *package = scalloc(sizeof(struct ev_io));
675 ev_io_init(package, ipc_receive_message, client, EV_READ);
676 ev_io_start(EV_A_ package);
678 DLOG("IPC: new client connected\n");
680 ipc_client *new = scalloc(sizeof(ipc_client));
683 TAILQ_INSERT_TAIL(&all_clients, new, clients);
687 * Creates the UNIX domain socket at the given path, sets it to non-blocking
688 * mode, bind()s and listen()s on it.
691 int ipc_create_socket(const char *filename) {
694 FREE(current_socketpath);
696 char *resolved = resolve_tilde(filename);
697 DLOG("Creating IPC-socket at %s\n", resolved);
698 char *copy = sstrdup(resolved);
699 const char *dir = dirname(copy);
700 if (!path_exists(dir))
704 /* Unlink the unix domain socket before */
707 if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
713 (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
715 struct sockaddr_un addr;
716 memset(&addr, 0, sizeof(struct sockaddr_un));
717 addr.sun_family = AF_LOCAL;
718 strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
719 if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_un)) < 0) {
725 set_nonblock(sockfd);
727 if (listen(sockfd, 5) < 0) {
733 current_socketpath = resolved;