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 char *reply = parse_cmd((const char*)command);
151 char *save_reply = reply;
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));
163 static void dump_rect(yajl_gen gen, const char *name, Rect r) {
173 y(integer, r.height);
177 void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
180 y(integer, (long int)con);
183 y(integer, con->type);
186 switch (con->orientation) {
199 if (con->percent == 0.0)
201 else y(double, con->percent);
204 y(bool, con->urgent);
207 y(bool, (con == focused));
210 switch (con->layout) {
229 switch (con->border_style) {
241 dump_rect(gen, "rect", con->rect);
242 dump_rect(gen, "window_rect", con->window_rect);
243 dump_rect(gen, "geometry", con->geometry);
248 if (con->type == CT_WORKSPACE) {
250 y(integer, con->num);
255 y(integer, con->window->id);
261 if (con->type != CT_DOCKAREA || !inplace_restart) {
262 TAILQ_FOREACH(node, &(con->nodes_head), nodes) {
263 dump_node(gen, node, inplace_restart);
268 ystr("floating_nodes");
270 TAILQ_FOREACH(node, &(con->floating_head), floating_windows) {
271 dump_node(gen, node, inplace_restart);
277 TAILQ_FOREACH(node, &(con->focus_head), nodes) {
278 y(integer, (long int)node);
282 ystr("fullscreen_mode");
283 y(integer, con->fullscreen_mode);
288 TAILQ_FOREACH(match, &(con->swallow_head), matches) {
289 if (match->dock != -1) {
292 y(integer, match->dock);
293 ystr("insert_where");
294 y(integer, match->insert_where);
298 /* TODO: the other swallow keys */
301 if (inplace_restart) {
302 if (con->window != NULL) {
305 y(integer, con->window->id);
315 setlocale(LC_NUMERIC, "C");
317 yajl_gen gen = yajl_gen_alloc(NULL);
319 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
321 dump_node(gen, croot, false);
322 setlocale(LC_NUMERIC, "");
324 const unsigned char *payload;
330 y(get_buf, &payload, &length);
332 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_TREE, length);
337 * Formats the reply message for a GET_WORKSPACES request and sends it to the
341 IPC_HANDLER(get_workspaces) {
343 yajl_gen gen = yajl_gen_alloc(NULL);
345 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
349 Con *focused_ws = con_get_workspace(focused);
352 TAILQ_FOREACH(output, &(croot->nodes_head), nodes) {
354 TAILQ_FOREACH(ws, &(output_get_content(output)->nodes_head), nodes) {
355 assert(ws->type == CT_WORKSPACE);
361 else y(integer, ws->num);
367 y(bool, workspace_is_visible(ws));
370 y(bool, ws == focused_ws);
375 y(integer, ws->rect.x);
377 y(integer, ws->rect.y);
379 y(integer, ws->rect.width);
381 y(integer, ws->rect.height);
396 const unsigned char *payload;
402 y(get_buf, &payload, &length);
404 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_WORKSPACES, length);
409 * Formats the reply message for a GET_OUTPUTS request and sends it to the
413 IPC_HANDLER(get_outputs) {
415 yajl_gen gen = yajl_gen_alloc(NULL);
417 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
422 TAILQ_FOREACH(output, &outputs, outputs) {
429 y(bool, output->active);
434 y(integer, output->rect.x);
436 y(integer, output->rect.y);
438 y(integer, output->rect.width);
440 y(integer, output->rect.height);
443 ystr("current_workspace");
445 if (output->con && (ws = con_get_fullscreen_con(output->con, CF_OUTPUT)))
454 const unsigned char *payload;
460 y(get_buf, &payload, &length);
462 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_OUTPUTS, length);
467 * Callback for the YAJL parser (will be called when a string is parsed).
471 static int add_subscription(void *extra, const unsigned char *s,
474 static int add_subscription(void *extra, const unsigned char *s,
477 ipc_client *client = extra;
479 DLOG("should add subscription to extra %p, sub %.*s\n", client, len, s);
480 int event = client->num_events;
482 client->num_events++;
483 client->events = realloc(client->events, client->num_events * sizeof(char*));
484 /* We copy the string because it is not null-terminated and strndup()
485 * is missing on some BSD systems */
486 client->events[event] = scalloc(len+1);
487 memcpy(client->events[event], s, len);
489 DLOG("client is now subscribed to:\n");
490 for (int i = 0; i < client->num_events; i++)
491 DLOG("event %s\n", client->events[i]);
498 * Subscribes this connection to the event types which were given as a JSON
499 * serialized array in the payload field of the message.
502 IPC_HANDLER(subscribe) {
504 yajl_callbacks callbacks;
506 ipc_client *current, *client = NULL;
508 /* Search the ipc_client structure for this connection */
509 TAILQ_FOREACH(current, &all_clients, clients) {
510 if (current->fd != fd)
517 if (client == NULL) {
518 ELOG("Could not find ipc_client data structure for fd %d\n", fd);
522 /* Setup the JSON parser */
523 memset(&callbacks, 0, sizeof(yajl_callbacks));
524 callbacks.yajl_string = add_subscription;
527 p = yajl_alloc(&callbacks, NULL, (void*)client);
529 p = yajl_alloc(&callbacks, NULL, NULL, (void*)client);
531 stat = yajl_parse(p, (const unsigned char*)message, message_size);
532 if (stat != yajl_status_ok) {
534 err = yajl_get_error(p, true, (const unsigned char*)message,
536 ELOG("YAJL parse error: %s\n", err);
537 yajl_free_error(p, err);
539 const char *reply = "{\"success\":false}";
540 ipc_send_message(fd, (const unsigned char*)reply,
541 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
546 const char *reply = "{\"success\":true}";
547 ipc_send_message(fd, (const unsigned char*)reply,
548 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
551 /* The index of each callback function corresponds to the numeric
552 * value of the message type (see include/i3/ipc.h) */
553 handler_t handlers[5] = {
555 handle_get_workspaces,
562 * Handler for activity on a client connection, receives a message from a
565 * For now, the maximum message size is 2048. I’m not sure for what the
566 * IPC interface will be used in the future, thus I’m not implementing a
567 * mechanism for arbitrarily long messages, as it seems like overkill
571 static void ipc_receive_message(EV_P_ struct ev_io *w, int revents) {
573 int n = read(w->fd, buf, sizeof(buf));
575 /* On error or an empty message, we close the connection */
578 /* FIXME: I get these when closing a client socket,
579 * therefore we just treat them as an error. Is this
581 if (errno == EAGAIN || errno == EWOULDBLOCK)
585 /* If not, there was some kind of error. We don’t bother
586 * and close the connection */
589 /* Delete the client from the list of clients */
591 TAILQ_FOREACH(current, &all_clients, clients) {
592 if (current->fd != w->fd)
595 for (int i = 0; i < current->num_events; i++)
596 free(current->events[i]);
597 /* We can call TAILQ_REMOVE because we break out of the
598 * TAILQ_FOREACH afterwards */
599 TAILQ_REMOVE(&all_clients, current, clients);
605 DLOG("IPC: client disconnected\n");
609 /* Terminate the message correctly */
612 /* Check if the message starts with the i3 IPC magic code */
613 if (n < strlen(I3_IPC_MAGIC)) {
614 DLOG("IPC: message too short, ignoring\n");
618 if (strncmp(buf, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
619 DLOG("IPC: message does not start with the IPC magic\n");
623 uint8_t *message = (uint8_t*)buf;
625 DLOG("IPC: n = %d\n", n);
626 message += strlen(I3_IPC_MAGIC);
627 n -= strlen(I3_IPC_MAGIC);
629 /* The next 32 bit after the magic are the message size */
630 uint32_t message_size;
631 memcpy(&message_size, (uint32_t*)message, sizeof(uint32_t));
632 message += sizeof(uint32_t);
633 n -= sizeof(uint32_t);
635 if (message_size > n) {
636 DLOG("IPC: Either the message size was wrong or the message was not read completely, dropping\n");
640 /* The last 32 bits of the header are the message type */
641 uint32_t message_type;
642 memcpy(&message_type, (uint32_t*)message, sizeof(uint32_t));
643 message += sizeof(uint32_t);
644 n -= sizeof(uint32_t);
646 if (message_type >= (sizeof(handlers) / sizeof(handler_t)))
647 DLOG("Unhandled message type: %d\n", message_type);
649 handler_t h = handlers[message_type];
650 h(w->fd, message, n, message_size, message_type);
653 message += message_size;
658 * Handler for activity on the listening socket, meaning that a new client
659 * has just connected and we should accept() him. Sets up the event handler
660 * for activity on the new connection and inserts the file descriptor into
661 * the list of clients.
664 void ipc_new_client(EV_P_ struct ev_io *w, int revents) {
665 struct sockaddr_un peer;
666 socklen_t len = sizeof(struct sockaddr_un);
668 if ((client = accept(w->fd, (struct sockaddr*)&peer, &len)) < 0) {
671 else perror("accept()");
675 set_nonblock(client);
677 struct ev_io *package = scalloc(sizeof(struct ev_io));
678 ev_io_init(package, ipc_receive_message, client, EV_READ);
679 ev_io_start(EV_A_ package);
681 DLOG("IPC: new client connected on fd %d\n", w->fd);
683 ipc_client *new = scalloc(sizeof(ipc_client));
686 TAILQ_INSERT_TAIL(&all_clients, new, clients);
690 * Creates the UNIX domain socket at the given path, sets it to non-blocking
691 * mode, bind()s and listen()s on it.
694 int ipc_create_socket(const char *filename) {
697 FREE(current_socketpath);
699 char *resolved = resolve_tilde(filename);
700 DLOG("Creating IPC-socket at %s\n", resolved);
701 char *copy = sstrdup(resolved);
702 const char *dir = dirname(copy);
703 if (!path_exists(dir))
707 /* Unlink the unix domain socket before */
710 if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
716 (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
718 struct sockaddr_un addr;
719 memset(&addr, 0, sizeof(struct sockaddr_un));
720 addr.sun_family = AF_LOCAL;
721 strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
722 if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_un)) < 0) {
728 set_nonblock(sockfd);
730 if (listen(sockfd, 5) < 0) {
736 current_socketpath = resolved;