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 /* Shorter names for all those yajl_gen_* functions */
24 #define y(x, ...) yajl_gen_ ## x (gen, ##__VA_ARGS__)
25 #define ystr(str) yajl_gen_string(gen, (unsigned char*)str, strlen(str))
27 TAILQ_HEAD(ipc_client_head, ipc_client) all_clients = TAILQ_HEAD_INITIALIZER(all_clients);
30 * Puts the given socket file descriptor into non-blocking mode or dies if
31 * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
32 * IPC model because we should by no means block the window manager.
35 static void set_nonblock(int sockfd) {
36 int flags = fcntl(sockfd, F_GETFL, 0);
38 if (fcntl(sockfd, F_SETFL, flags) < 0)
39 err(-1, "Could not set O_NONBLOCK");
43 * Emulates mkdir -p (creates any missing folders)
46 static bool mkdirp(const char *path) {
47 if (mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) == 0)
49 if (errno != ENOENT) {
50 ELOG("mkdir(%s) failed: %s\n", path, strerror(errno));
53 char *copy = strdup(path);
54 /* strip trailing slashes, if any */
55 while (copy[strlen(copy)-1] == '/')
56 copy[strlen(copy)-1] = '\0';
58 char *sep = strrchr(copy, '/');
64 result = mkdirp(path);
70 static void ipc_send_message(int fd, const unsigned char *payload,
71 int message_type, int message_size) {
72 int buffer_size = strlen("i3-ipc") + sizeof(uint32_t) +
73 sizeof(uint32_t) + message_size;
74 char msg[buffer_size];
77 strcpy(walk, "i3-ipc");
78 walk += strlen("i3-ipc");
79 memcpy(walk, &message_size, sizeof(uint32_t));
80 walk += sizeof(uint32_t);
81 memcpy(walk, &message_type, sizeof(uint32_t));
82 walk += sizeof(uint32_t);
83 memcpy(walk, payload, message_size);
86 int bytes_to_go = buffer_size;
87 while (sent_bytes < bytes_to_go) {
88 int n = write(fd, msg + sent_bytes, bytes_to_go);
90 DLOG("write() failed: %s\n", strerror(errno));
100 * Sends the specified event to all IPC clients which are currently connected
101 * and subscribed to this kind of event.
104 void ipc_send_event(const char *event, uint32_t message_type, const char *payload) {
106 TAILQ_FOREACH(current, &all_clients, clients) {
107 /* see if this client is interested in this event */
108 bool interested = false;
109 for (int i = 0; i < current->num_events; i++) {
110 if (strcasecmp(current->events[i], event) != 0)
118 ipc_send_message(current->fd, (const unsigned char*)payload,
119 message_type, strlen(payload));
124 * Calls shutdown() on each socket and closes it. This function to be called
125 * when exiting or restarting only!
128 void ipc_shutdown() {
130 TAILQ_FOREACH(current, &all_clients, clients) {
131 shutdown(current->fd, SHUT_RDWR);
137 * Executes the command and returns whether it could be successfully parsed
138 * or not (at the moment, always returns true).
141 IPC_HANDLER(command) {
142 /* To get a properly terminated buffer, we copy
143 * message_size bytes out of the buffer */
144 char *command = scalloc(message_size + 1);
145 strncpy(command, (const char*)message, message_size);
146 LOG("IPC: received: *%s*\n", command);
147 const char *reply = parse_cmd((const char*)command);
151 /* If no reply was provided, we just use the default success message */
153 reply = "{\"success\":true}";
154 ipc_send_message(fd, (const unsigned char*)reply,
155 I3_IPC_REPLY_TYPE_COMMAND, strlen(reply));
158 void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
161 y(integer, (long int)con);
164 y(integer, con->type);
167 y(integer, con->orientation);
170 y(integer, con->urgent);
173 y(integer, (con == focused));
176 y(integer, con->layout);
179 y(integer, con->border_style);
184 y(integer, con->rect.x);
186 y(integer, con->rect.y);
188 y(integer, con->rect.width);
190 y(integer, con->rect.height);
198 y(integer, con->window->id);
204 TAILQ_FOREACH(node, &(con->nodes_head), nodes) {
205 dump_node(gen, node, inplace_restart);
209 ystr("floating_nodes");
211 TAILQ_FOREACH(node, &(con->floating_head), floating_windows) {
212 dump_node(gen, node, inplace_restart);
218 TAILQ_FOREACH(node, &(con->focus_head), nodes) {
219 y(integer, (long int)node);
223 ystr("fullscreen_mode");
224 y(integer, con->fullscreen_mode);
226 if (inplace_restart) {
227 if (con->window != NULL) {
232 y(integer, con->window->id);
242 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
243 dump_node(gen, croot, false);
245 const unsigned char *payload;
247 y(get_buf, &payload, &length);
249 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_TREE, length);
254 * Formats the reply message for a GET_WORKSPACES request and sends it to the
258 IPC_HANDLER(get_workspaces) {
259 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
262 Con *focused_ws = con_get_workspace(focused);
265 TAILQ_FOREACH(output, &(croot->nodes_head), nodes) {
267 TAILQ_FOREACH(ws, &(output->nodes_head), nodes) {
268 assert(ws->type == CT_WORKSPACE);
274 else y(integer, ws->num);
280 y(bool, workspace_is_visible(ws));
283 y(bool, ws == focused_ws);
288 y(integer, ws->rect.x);
290 y(integer, ws->rect.y);
292 y(integer, ws->rect.width);
294 y(integer, ws->rect.height);
309 const unsigned char *payload;
311 y(get_buf, &payload, &length);
313 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_WORKSPACES, length);
318 * Formats the reply message for a GET_OUTPUTS request and sends it to the
322 IPC_HANDLER(get_outputs) {
323 yajl_gen gen = yajl_gen_alloc(NULL, NULL);
327 TAILQ_FOREACH(output, &outputs, outputs) {
334 y(bool, output->active);
339 y(integer, output->rect.x);
341 y(integer, output->rect.y);
343 y(integer, output->rect.width);
345 y(integer, output->rect.height);
348 ystr("current_workspace");
350 if (output->con && (ws = con_get_fullscreen_con(output->con)))
359 const unsigned char *payload;
361 y(get_buf, &payload, &length);
363 ipc_send_message(fd, payload, I3_IPC_REPLY_TYPE_OUTPUTS, length);
368 * Callback for the YAJL parser (will be called when a string is parsed).
371 static int add_subscription(void *extra, const unsigned char *s,
373 ipc_client *client = extra;
375 DLOG("should add subscription to extra %p, sub %.*s\n", client, len, s);
376 int event = client->num_events;
378 client->num_events++;
379 client->events = realloc(client->events, client->num_events * sizeof(char*));
380 /* We copy the string because it is not null-terminated and strndup()
381 * is missing on some BSD systems */
382 client->events[event] = scalloc(len+1);
383 memcpy(client->events[event], s, len);
385 DLOG("client is now subscribed to:\n");
386 for (int i = 0; i < client->num_events; i++)
387 DLOG("event %s\n", client->events[i]);
394 * Subscribes this connection to the event types which were given as a JSON
395 * serialized array in the payload field of the message.
398 IPC_HANDLER(subscribe) {
400 yajl_callbacks callbacks;
402 ipc_client *current, *client = NULL;
404 /* Search the ipc_client structure for this connection */
405 TAILQ_FOREACH(current, &all_clients, clients) {
406 if (current->fd != fd)
413 if (client == NULL) {
414 ELOG("Could not find ipc_client data structure for fd %d\n", fd);
418 /* Setup the JSON parser */
419 memset(&callbacks, 0, sizeof(yajl_callbacks));
420 callbacks.yajl_string = add_subscription;
422 p = yajl_alloc(&callbacks, NULL, NULL, (void*)client);
423 stat = yajl_parse(p, (const unsigned char*)message, message_size);
424 if (stat != yajl_status_ok) {
426 err = yajl_get_error(p, true, (const unsigned char*)message,
428 ELOG("YAJL parse error: %s\n", err);
429 yajl_free_error(p, err);
431 const char *reply = "{\"success\":false}";
432 ipc_send_message(fd, (const unsigned char*)reply,
433 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
438 const char *reply = "{\"success\":true}";
439 ipc_send_message(fd, (const unsigned char*)reply,
440 I3_IPC_REPLY_TYPE_SUBSCRIBE, strlen(reply));
443 /* The index of each callback function corresponds to the numeric
444 * value of the message type (see include/i3/ipc.h) */
445 handler_t handlers[5] = {
447 handle_get_workspaces,
454 * Handler for activity on a client connection, receives a message from a
457 * For now, the maximum message size is 2048. I’m not sure for what the
458 * IPC interface will be used in the future, thus I’m not implementing a
459 * mechanism for arbitrarily long messages, as it seems like overkill
463 static void ipc_receive_message(EV_P_ struct ev_io *w, int revents) {
465 int n = read(w->fd, buf, sizeof(buf));
467 /* On error or an empty message, we close the connection */
470 /* FIXME: I get these when closing a client socket,
471 * therefore we just treat them as an error. Is this
473 if (errno == EAGAIN || errno == EWOULDBLOCK)
477 /* If not, there was some kind of error. We don’t bother
478 * and close the connection */
481 /* Delete the client from the list of clients */
483 TAILQ_FOREACH(current, &all_clients, clients) {
484 if (current->fd != w->fd)
487 for (int i = 0; i < current->num_events; i++)
488 free(current->events[i]);
489 /* We can call TAILQ_REMOVE because we break out of the
490 * TAILQ_FOREACH afterwards */
491 TAILQ_REMOVE(&all_clients, current, clients);
497 DLOG("IPC: client disconnected\n");
501 /* Terminate the message correctly */
504 /* Check if the message starts with the i3 IPC magic code */
505 if (n < strlen(I3_IPC_MAGIC)) {
506 DLOG("IPC: message too short, ignoring\n");
510 if (strncmp(buf, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
511 DLOG("IPC: message does not start with the IPC magic\n");
515 uint8_t *message = (uint8_t*)buf;
517 DLOG("IPC: n = %d\n", n);
518 message += strlen(I3_IPC_MAGIC);
519 n -= strlen(I3_IPC_MAGIC);
521 /* The next 32 bit after the magic are the message size */
522 uint32_t message_size = *((uint32_t*)message);
523 message += sizeof(uint32_t);
524 n -= sizeof(uint32_t);
526 if (message_size > n) {
527 DLOG("IPC: Either the message size was wrong or the message was not read completely, dropping\n");
531 /* The last 32 bits of the header are the message type */
532 uint32_t message_type = *((uint32_t*)message);
533 message += sizeof(uint32_t);
534 n -= sizeof(uint32_t);
536 if (message_type >= (sizeof(handlers) / sizeof(handler_t)))
537 DLOG("Unhandled message type: %d\n", message_type);
539 handler_t h = handlers[message_type];
540 h(w->fd, message, n, message_size, message_type);
543 message += message_size;
548 * Handler for activity on the listening socket, meaning that a new client
549 * has just connected and we should accept() him. Sets up the event handler
550 * for activity on the new connection and inserts the file descriptor into
551 * the list of clients.
554 void ipc_new_client(EV_P_ struct ev_io *w, int revents) {
555 struct sockaddr_un peer;
556 socklen_t len = sizeof(struct sockaddr_un);
558 if ((client = accept(w->fd, (struct sockaddr*)&peer, &len)) < 0) {
561 else perror("accept()");
565 set_nonblock(client);
567 struct ev_io *package = scalloc(sizeof(struct ev_io));
568 ev_io_init(package, ipc_receive_message, client, EV_READ);
569 ev_io_start(EV_A_ package);
571 DLOG("IPC: new client connected\n");
573 ipc_client *new = scalloc(sizeof(ipc_client));
576 TAILQ_INSERT_TAIL(&all_clients, new, clients);
580 * Creates the UNIX domain socket at the given path, sets it to non-blocking
581 * mode, bind()s and listen()s on it.
584 int ipc_create_socket(const char *filename) {
587 char *resolved = resolve_tilde(filename);
588 DLOG("Creating IPC-socket at %s\n", resolved);
589 char *copy = sstrdup(resolved);
590 const char *dir = dirname(copy);
591 if (!path_exists(dir))
595 /* Unlink the unix domain socket before */
598 if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
604 (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
606 struct sockaddr_un addr;
607 memset(&addr, 0, sizeof(struct sockaddr_un));
608 addr.sun_family = AF_LOCAL;
609 strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
610 if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_un)) < 0) {
617 set_nonblock(sockfd);
619 if (listen(sockfd, 5) < 0) {