Commit | Line | Data |
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a58c490f | 1 | /* |
ab5be9fa | 2 | * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
a58c490f | 3 | * |
ab5be9fa | 4 | * SPDX-License-Identifier: LGPL-2.1-only |
a58c490f | 5 | * |
a58c490f JG |
6 | */ |
7 | ||
c9e313bc SM |
8 | #include <lttng/notification/notification-internal.hpp> |
9 | #include <lttng/notification/channel-internal.hpp> | |
10 | #include <lttng/condition/condition-internal.hpp> | |
a58c490f | 11 | #include <lttng/endpoint.h> |
c9e313bc SM |
12 | #include <common/defaults.hpp> |
13 | #include <common/error.hpp> | |
14 | #include <common/dynamic-buffer.hpp> | |
15 | #include <common/utils.hpp> | |
16 | #include <common/defaults.hpp> | |
17 | #include <common/payload.hpp> | |
18 | #include <common/payload-view.hpp> | |
19 | #include <common/unix.hpp> | |
20 | #include "lttng-ctl-helper.hpp" | |
21 | #include <common/compat/poll.hpp> | |
a58c490f JG |
22 | |
23 | static | |
24 | int handshake(struct lttng_notification_channel *channel); | |
25 | ||
26 | /* | |
27 | * Populates the reception buffer with the next complete message. | |
1d757b1c | 28 | * The caller must acquire the channel's lock. |
a58c490f JG |
29 | */ |
30 | static | |
31 | int receive_message(struct lttng_notification_channel *channel) | |
32 | { | |
33 | ssize_t ret; | |
34 | struct lttng_notification_channel_message msg; | |
35 | ||
882093ee | 36 | lttng_payload_clear(&channel->reception_payload); |
a58c490f JG |
37 | |
38 | ret = lttcomm_recv_unix_sock(channel->socket, &msg, sizeof(msg)); | |
39 | if (ret <= 0) { | |
40 | ret = -1; | |
41 | goto error; | |
42 | } | |
43 | ||
44 | if (msg.size > DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE) { | |
45 | ret = -1; | |
46 | goto error; | |
47 | } | |
48 | ||
49 | /* Add message header at buffer's start. */ | |
882093ee | 50 | ret = lttng_dynamic_buffer_append(&channel->reception_payload.buffer, &msg, |
a58c490f JG |
51 | sizeof(msg)); |
52 | if (ret) { | |
53 | goto error; | |
54 | } | |
55 | ||
63ae8472 JR |
56 | if (msg.size == 0) { |
57 | goto skip_payload; | |
58 | } | |
59 | ||
a58c490f | 60 | /* Reserve space for the payload. */ |
882093ee JR |
61 | ret = lttng_dynamic_buffer_set_size(&channel->reception_payload.buffer, |
62 | channel->reception_payload.buffer.size + msg.size); | |
a58c490f JG |
63 | if (ret) { |
64 | goto error; | |
65 | } | |
66 | ||
67 | /* Receive message payload. */ | |
68 | ret = lttcomm_recv_unix_sock(channel->socket, | |
882093ee | 69 | channel->reception_payload.buffer.data + sizeof(msg), msg.size); |
a58c490f JG |
70 | if (ret < (ssize_t) msg.size) { |
71 | ret = -1; | |
72 | goto error; | |
73 | } | |
882093ee | 74 | |
63ae8472 | 75 | skip_payload: |
882093ee JR |
76 | /* Receive message fds. */ |
77 | if (msg.fds != 0) { | |
78 | ret = lttcomm_recv_payload_fds_unix_sock(channel->socket, | |
79 | msg.fds, &channel->reception_payload); | |
80 | if (ret < sizeof(int) * msg.fds) { | |
81 | ret = -1; | |
82 | goto error; | |
83 | } | |
84 | } | |
a58c490f JG |
85 | ret = 0; |
86 | end: | |
87 | return ret; | |
88 | error: | |
882093ee | 89 | lttng_payload_clear(&channel->reception_payload); |
a58c490f JG |
90 | goto end; |
91 | } | |
92 | ||
93 | static | |
94 | enum lttng_notification_channel_message_type get_current_message_type( | |
95 | struct lttng_notification_channel *channel) | |
96 | { | |
97 | struct lttng_notification_channel_message *msg; | |
98 | ||
a0377dfe | 99 | LTTNG_ASSERT(channel->reception_payload.buffer.size >= sizeof(*msg)); |
a58c490f JG |
100 | |
101 | msg = (struct lttng_notification_channel_message *) | |
882093ee | 102 | channel->reception_payload.buffer.data; |
a58c490f JG |
103 | return (enum lttng_notification_channel_message_type) msg->type; |
104 | } | |
105 | ||
106 | static | |
107 | struct lttng_notification *create_notification_from_current_message( | |
108 | struct lttng_notification_channel *channel) | |
109 | { | |
110 | ssize_t ret; | |
111 | struct lttng_notification *notification = NULL; | |
a58c490f | 112 | |
882093ee | 113 | if (channel->reception_payload.buffer.size <= |
a58c490f JG |
114 | sizeof(struct lttng_notification_channel_message)) { |
115 | goto end; | |
116 | } | |
117 | ||
c0a66c84 | 118 | { |
882093ee JR |
119 | struct lttng_payload_view view = lttng_payload_view_from_payload( |
120 | &channel->reception_payload, | |
c0a66c84 JG |
121 | sizeof(struct lttng_notification_channel_message), |
122 | -1); | |
123 | ||
124 | ret = lttng_notification_create_from_payload( | |
125 | &view, ¬ification); | |
126 | } | |
a58c490f | 127 | |
882093ee | 128 | if (ret != channel->reception_payload.buffer.size - |
a58c490f JG |
129 | sizeof(struct lttng_notification_channel_message)) { |
130 | lttng_notification_destroy(notification); | |
131 | notification = NULL; | |
132 | goto end; | |
133 | } | |
134 | end: | |
135 | return notification; | |
136 | } | |
137 | ||
138 | struct lttng_notification_channel *lttng_notification_channel_create( | |
139 | struct lttng_endpoint *endpoint) | |
140 | { | |
141 | int fd, ret; | |
142 | bool is_in_tracing_group = false, is_root = false; | |
143 | char *sock_path = NULL; | |
144 | struct lttng_notification_channel *channel = NULL; | |
145 | ||
146 | if (!endpoint || | |
147 | endpoint != lttng_session_daemon_notification_endpoint) { | |
148 | goto end; | |
149 | } | |
150 | ||
64803277 | 151 | sock_path = calloc<char>(LTTNG_PATH_MAX); |
a58c490f JG |
152 | if (!sock_path) { |
153 | goto end; | |
154 | } | |
155 | ||
64803277 | 156 | channel = zmalloc<lttng_notification_channel>(); |
a58c490f JG |
157 | if (!channel) { |
158 | goto end; | |
159 | } | |
160 | channel->socket = -1; | |
161 | pthread_mutex_init(&channel->lock, NULL); | |
882093ee | 162 | lttng_payload_init(&channel->reception_payload); |
a58c490f JG |
163 | CDS_INIT_LIST_HEAD(&channel->pending_notifications.list); |
164 | ||
165 | is_root = (getuid() == 0); | |
166 | if (!is_root) { | |
167 | is_in_tracing_group = lttng_check_tracing_group(); | |
168 | } | |
169 | ||
170 | if (is_root || is_in_tracing_group) { | |
e1b624d0 | 171 | ret = lttng_strncpy(sock_path, |
a58c490f JG |
172 | DEFAULT_GLOBAL_NOTIFICATION_CHANNEL_UNIX_SOCK, |
173 | LTTNG_PATH_MAX); | |
e1b624d0 JG |
174 | if (ret) { |
175 | ret = -LTTNG_ERR_INVALID; | |
176 | goto error; | |
177 | } | |
178 | ||
a58c490f JG |
179 | ret = lttcomm_connect_unix_sock(sock_path); |
180 | if (ret >= 0) { | |
181 | fd = ret; | |
182 | goto set_fd; | |
183 | } | |
184 | } | |
185 | ||
186 | /* Fallback to local session daemon. */ | |
187 | ret = snprintf(sock_path, LTTNG_PATH_MAX, | |
188 | DEFAULT_HOME_NOTIFICATION_CHANNEL_UNIX_SOCK, | |
189 | utils_get_home_dir()); | |
190 | if (ret < 0 || ret >= LTTNG_PATH_MAX) { | |
191 | goto error; | |
192 | } | |
193 | ||
194 | ret = lttcomm_connect_unix_sock(sock_path); | |
195 | if (ret < 0) { | |
196 | goto error; | |
197 | } | |
198 | fd = ret; | |
199 | ||
200 | set_fd: | |
201 | channel->socket = fd; | |
202 | ||
203 | ret = handshake(channel); | |
204 | if (ret) { | |
205 | goto error; | |
206 | } | |
207 | end: | |
208 | free(sock_path); | |
209 | return channel; | |
210 | error: | |
211 | lttng_notification_channel_destroy(channel); | |
212 | channel = NULL; | |
213 | goto end; | |
214 | } | |
215 | ||
216 | enum lttng_notification_channel_status | |
217 | lttng_notification_channel_get_next_notification( | |
218 | struct lttng_notification_channel *channel, | |
219 | struct lttng_notification **_notification) | |
220 | { | |
221 | int ret; | |
222 | struct lttng_notification *notification = NULL; | |
223 | enum lttng_notification_channel_status status = | |
224 | LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; | |
d977a743 | 225 | struct lttng_poll_event events; |
a58c490f JG |
226 | |
227 | if (!channel || !_notification) { | |
228 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; | |
229 | goto end; | |
230 | } | |
231 | ||
94a61469 JG |
232 | pthread_mutex_lock(&channel->lock); |
233 | ||
a58c490f JG |
234 | if (channel->pending_notifications.count) { |
235 | struct pending_notification *pending_notification; | |
236 | ||
a0377dfe | 237 | LTTNG_ASSERT(!cds_list_empty(&channel->pending_notifications.list)); |
a58c490f JG |
238 | |
239 | /* Deliver one of the pending notifications. */ | |
240 | pending_notification = cds_list_first_entry( | |
241 | &channel->pending_notifications.list, | |
242 | struct pending_notification, | |
243 | node); | |
244 | notification = pending_notification->notification; | |
245 | if (!notification) { | |
246 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_NOTIFICATIONS_DROPPED; | |
247 | } | |
248 | cds_list_del(&pending_notification->node); | |
249 | channel->pending_notifications.count--; | |
250 | free(pending_notification); | |
94a61469 | 251 | goto end_unlock; |
f83bcd90 JG |
252 | } |
253 | ||
254 | /* | |
d977a743 MD |
255 | * Block on interruptible epoll/poll() instead of the message reception |
256 | * itself as the recvmsg() wrappers always restart on EINTR. We choose | |
257 | * to wait using interruptible epoll/poll() in order to: | |
f83bcd90 JG |
258 | * 1) Return if a signal occurs, |
259 | * 2) Not deal with partially received messages. | |
260 | * | |
261 | * The drawback to this approach is that we assume that messages | |
262 | * are complete/well formed. If a message is shorter than its | |
263 | * announced length, receive_message() will block on recvmsg() | |
264 | * and never return (even if a signal is received). | |
265 | */ | |
d977a743 MD |
266 | ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); |
267 | if (ret < 0) { | |
268 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
269 | goto end_unlock; | |
270 | } | |
1524f98c | 271 | ret = lttng_poll_add(&events, channel->socket, LPOLLIN); |
d977a743 MD |
272 | if (ret < 0) { |
273 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
274 | goto end_clean_poll; | |
275 | } | |
276 | ret = lttng_poll_wait_interruptible(&events, -1); | |
277 | if (ret <= 0) { | |
278 | status = (ret == -1 && errno == EINTR) ? | |
f83bcd90 JG |
279 | LTTNG_NOTIFICATION_CHANNEL_STATUS_INTERRUPTED : |
280 | LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 281 | goto end_clean_poll; |
a58c490f JG |
282 | } |
283 | ||
a58c490f JG |
284 | ret = receive_message(channel); |
285 | if (ret) { | |
286 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 287 | goto end_clean_poll; |
a58c490f JG |
288 | } |
289 | ||
290 | switch (get_current_message_type(channel)) { | |
291 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION: | |
292 | notification = create_notification_from_current_message( | |
293 | channel); | |
294 | if (!notification) { | |
295 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 296 | goto end_clean_poll; |
a58c490f JG |
297 | } |
298 | break; | |
299 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED: | |
300 | /* No payload to consume. */ | |
301 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_NOTIFICATIONS_DROPPED; | |
302 | break; | |
303 | default: | |
304 | /* Protocol error. */ | |
305 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 306 | goto end_clean_poll; |
a58c490f JG |
307 | } |
308 | ||
d977a743 MD |
309 | end_clean_poll: |
310 | lttng_poll_clean(&events); | |
a58c490f JG |
311 | end_unlock: |
312 | pthread_mutex_unlock(&channel->lock); | |
a57a7f22 | 313 | *_notification = notification; |
a58c490f | 314 | end: |
a58c490f JG |
315 | return status; |
316 | } | |
317 | ||
318 | static | |
319 | int enqueue_dropped_notification( | |
320 | struct lttng_notification_channel *channel) | |
321 | { | |
322 | int ret = 0; | |
323 | struct pending_notification *pending_notification; | |
324 | struct cds_list_head *last_element = | |
325 | channel->pending_notifications.list.prev; | |
326 | ||
327 | pending_notification = caa_container_of(last_element, | |
328 | struct pending_notification, node); | |
329 | if (!pending_notification->notification) { | |
330 | /* | |
331 | * The last enqueued notification indicates dropped | |
332 | * notifications; there is nothing to do as we group | |
333 | * dropped notifications together. | |
334 | */ | |
335 | goto end; | |
336 | } | |
337 | ||
338 | if (channel->pending_notifications.count >= | |
339 | DEFAULT_CLIENT_MAX_QUEUED_NOTIFICATIONS_COUNT && | |
340 | pending_notification->notification) { | |
341 | /* | |
342 | * Discard the last enqueued notification to indicate | |
343 | * that notifications were dropped at this point. | |
344 | */ | |
345 | lttng_notification_destroy( | |
346 | pending_notification->notification); | |
347 | pending_notification->notification = NULL; | |
348 | goto end; | |
349 | } | |
350 | ||
64803277 | 351 | pending_notification = zmalloc<struct pending_notification>(); |
a58c490f JG |
352 | if (!pending_notification) { |
353 | ret = -1; | |
354 | goto end; | |
355 | } | |
356 | CDS_INIT_LIST_HEAD(&pending_notification->node); | |
357 | cds_list_add(&pending_notification->node, | |
358 | &channel->pending_notifications.list); | |
359 | channel->pending_notifications.count++; | |
360 | end: | |
361 | return ret; | |
362 | } | |
363 | ||
364 | static | |
365 | int enqueue_notification_from_current_message( | |
366 | struct lttng_notification_channel *channel) | |
367 | { | |
368 | int ret = 0; | |
369 | struct lttng_notification *notification; | |
370 | struct pending_notification *pending_notification; | |
371 | ||
372 | if (channel->pending_notifications.count >= | |
373 | DEFAULT_CLIENT_MAX_QUEUED_NOTIFICATIONS_COUNT) { | |
374 | /* Drop the notification. */ | |
375 | ret = enqueue_dropped_notification(channel); | |
376 | goto end; | |
377 | } | |
378 | ||
64803277 | 379 | pending_notification = zmalloc<struct pending_notification>(); |
a58c490f JG |
380 | if (!pending_notification) { |
381 | ret = -1; | |
382 | goto error; | |
383 | } | |
384 | CDS_INIT_LIST_HEAD(&pending_notification->node); | |
385 | ||
386 | notification = create_notification_from_current_message(channel); | |
387 | if (!notification) { | |
388 | ret = -1; | |
389 | goto error; | |
390 | } | |
391 | ||
392 | pending_notification->notification = notification; | |
393 | cds_list_add(&pending_notification->node, | |
394 | &channel->pending_notifications.list); | |
395 | channel->pending_notifications.count++; | |
396 | end: | |
397 | return ret; | |
398 | error: | |
399 | free(pending_notification); | |
400 | goto end; | |
401 | } | |
402 | ||
1d757b1c JG |
403 | enum lttng_notification_channel_status |
404 | lttng_notification_channel_has_pending_notification( | |
405 | struct lttng_notification_channel *channel, | |
406 | bool *_notification_pending) | |
407 | { | |
408 | int ret; | |
409 | enum lttng_notification_channel_status status = | |
410 | LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; | |
d977a743 | 411 | struct lttng_poll_event events; |
1d757b1c JG |
412 | |
413 | if (!channel || !_notification_pending) { | |
414 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; | |
415 | goto end; | |
416 | } | |
417 | ||
418 | pthread_mutex_lock(&channel->lock); | |
419 | ||
420 | if (channel->pending_notifications.count) { | |
421 | *_notification_pending = true; | |
422 | goto end_unlock; | |
423 | } | |
424 | ||
425 | if (channel->socket < 0) { | |
426 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_CLOSED; | |
427 | goto end_unlock; | |
428 | } | |
429 | ||
430 | /* | |
431 | * Check, without blocking, if data is available on the channel's | |
432 | * socket. If there is data available, it is safe to read (blocking) | |
433 | * on the socket for a message from the session daemon. | |
434 | * | |
435 | * Since all commands wait for the session daemon's reply before | |
436 | * releasing the channel's lock, the protocol only allows for | |
437 | * notifications and "notification dropped" messages to come | |
438 | * through. If we receive a different message type, it is | |
439 | * considered a protocol error. | |
440 | * | |
441 | * Note that this function is not guaranteed not to block. This | |
442 | * will block until our peer (the session daemon) has sent a complete | |
443 | * message if we see data available on the socket. If the peer does | |
444 | * not respect the protocol, this may block indefinitely. | |
445 | */ | |
d977a743 MD |
446 | ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); |
447 | if (ret < 0) { | |
448 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
449 | goto end_unlock; | |
450 | } | |
1524f98c | 451 | ret = lttng_poll_add(&events, channel->socket, LPOLLIN); |
d977a743 MD |
452 | if (ret < 0) { |
453 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
454 | goto end_clean_poll; | |
455 | } | |
456 | /* timeout = 0: return immediately. */ | |
457 | ret = lttng_poll_wait_interruptible(&events, 0); | |
1d757b1c JG |
458 | if (ret == 0) { |
459 | /* No data available. */ | |
460 | *_notification_pending = false; | |
d977a743 | 461 | goto end_clean_poll; |
1d757b1c JG |
462 | } else if (ret < 0) { |
463 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 464 | goto end_clean_poll; |
1d757b1c JG |
465 | } |
466 | ||
467 | /* Data available on socket. */ | |
468 | ret = receive_message(channel); | |
469 | if (ret) { | |
470 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 471 | goto end_clean_poll; |
1d757b1c JG |
472 | } |
473 | ||
474 | switch (get_current_message_type(channel)) { | |
475 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION: | |
476 | ret = enqueue_notification_from_current_message(channel); | |
477 | if (ret) { | |
d977a743 | 478 | goto end_clean_poll; |
1d757b1c JG |
479 | } |
480 | *_notification_pending = true; | |
481 | break; | |
482 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED: | |
483 | ret = enqueue_dropped_notification(channel); | |
484 | if (ret) { | |
d977a743 | 485 | goto end_clean_poll; |
1d757b1c JG |
486 | } |
487 | *_notification_pending = true; | |
488 | break; | |
489 | default: | |
490 | /* Protocol error. */ | |
491 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
d977a743 | 492 | goto end_clean_poll; |
1d757b1c JG |
493 | } |
494 | ||
d977a743 MD |
495 | end_clean_poll: |
496 | lttng_poll_clean(&events); | |
1d757b1c JG |
497 | end_unlock: |
498 | pthread_mutex_unlock(&channel->lock); | |
499 | end: | |
500 | return status; | |
501 | } | |
502 | ||
a58c490f JG |
503 | static |
504 | int receive_command_reply(struct lttng_notification_channel *channel, | |
505 | enum lttng_notification_channel_status *status) | |
506 | { | |
507 | int ret; | |
508 | struct lttng_notification_channel_command_reply *reply; | |
509 | ||
510 | while (true) { | |
511 | enum lttng_notification_channel_message_type msg_type; | |
512 | ||
513 | ret = receive_message(channel); | |
514 | if (ret) { | |
515 | goto end; | |
516 | } | |
517 | ||
518 | msg_type = get_current_message_type(channel); | |
519 | switch (msg_type) { | |
520 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY: | |
521 | goto exit_loop; | |
522 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION: | |
523 | ret = enqueue_notification_from_current_message( | |
524 | channel); | |
525 | if (ret) { | |
526 | goto end; | |
527 | } | |
528 | break; | |
529 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED: | |
530 | ret = enqueue_dropped_notification(channel); | |
531 | if (ret) { | |
532 | goto end; | |
533 | } | |
534 | break; | |
535 | case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE: | |
536 | { | |
537 | struct lttng_notification_channel_command_handshake *handshake; | |
538 | ||
539 | handshake = (struct lttng_notification_channel_command_handshake *) | |
882093ee | 540 | (channel->reception_payload.buffer.data + |
a58c490f JG |
541 | sizeof(struct lttng_notification_channel_message)); |
542 | channel->version.major = handshake->major; | |
543 | channel->version.minor = handshake->minor; | |
544 | channel->version.set = true; | |
545 | break; | |
546 | } | |
547 | default: | |
548 | ret = -1; | |
549 | goto end; | |
550 | } | |
551 | } | |
552 | ||
553 | exit_loop: | |
882093ee | 554 | if (channel->reception_payload.buffer.size < |
a58c490f JG |
555 | (sizeof(struct lttng_notification_channel_message) + |
556 | sizeof(*reply))) { | |
557 | /* Invalid message received. */ | |
558 | ret = -1; | |
559 | goto end; | |
560 | } | |
561 | ||
562 | reply = (struct lttng_notification_channel_command_reply *) | |
882093ee | 563 | (channel->reception_payload.buffer.data + |
a58c490f JG |
564 | sizeof(struct lttng_notification_channel_message)); |
565 | *status = (enum lttng_notification_channel_status) reply->status; | |
566 | end: | |
567 | return ret; | |
568 | } | |
569 | ||
570 | static | |
571 | int handshake(struct lttng_notification_channel *channel) | |
572 | { | |
573 | ssize_t ret; | |
574 | enum lttng_notification_channel_status status = | |
575 | LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; | |
576 | struct lttng_notification_channel_command_handshake handshake = { | |
577 | .major = LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR, | |
578 | .minor = LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR, | |
579 | }; | |
57fb67ac | 580 | struct lttng_notification_channel_message msg_header; |
a58c490f JG |
581 | char send_buffer[sizeof(msg_header) + sizeof(handshake)]; |
582 | ||
57fb67ac JG |
583 | msg_header.type = LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE; |
584 | msg_header.size = sizeof(handshake); | |
585 | msg_header.fds = 0; | |
586 | ||
a58c490f JG |
587 | memcpy(send_buffer, &msg_header, sizeof(msg_header)); |
588 | memcpy(send_buffer + sizeof(msg_header), &handshake, sizeof(handshake)); | |
589 | ||
590 | pthread_mutex_lock(&channel->lock); | |
591 | ||
01ea340e | 592 | ret = lttcomm_send_creds_unix_sock(channel->socket, send_buffer, |
a58c490f JG |
593 | sizeof(send_buffer)); |
594 | if (ret < 0) { | |
595 | goto end_unlock; | |
596 | } | |
597 | ||
598 | /* Receive handshake info from the sessiond. */ | |
599 | ret = receive_command_reply(channel, &status); | |
600 | if (ret < 0) { | |
601 | goto end_unlock; | |
602 | } | |
603 | ||
604 | if (!channel->version.set) { | |
605 | ret = -1; | |
606 | goto end_unlock; | |
607 | } | |
608 | ||
609 | if (channel->version.major != LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR) { | |
610 | ret = -1; | |
611 | goto end_unlock; | |
612 | } | |
613 | ||
614 | end_unlock: | |
615 | pthread_mutex_unlock(&channel->lock); | |
616 | return ret; | |
617 | } | |
618 | ||
619 | static | |
620 | enum lttng_notification_channel_status send_condition_command( | |
621 | struct lttng_notification_channel *channel, | |
622 | enum lttng_notification_channel_message_type type, | |
623 | const struct lttng_condition *condition) | |
624 | { | |
625 | int socket; | |
3647288f | 626 | ssize_t ret; |
a58c490f JG |
627 | enum lttng_notification_channel_status status = |
628 | LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; | |
c0a66c84 | 629 | struct lttng_payload payload; |
57fb67ac JG |
630 | struct lttng_notification_channel_message cmd_header; |
631 | ||
632 | cmd_header.type = (int8_t) type; | |
633 | cmd_header.size = 0; | |
634 | cmd_header.fds = 0; | |
a58c490f | 635 | |
c0a66c84 | 636 | lttng_payload_init(&payload); |
3647288f | 637 | |
a58c490f JG |
638 | if (!channel) { |
639 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; | |
640 | goto end; | |
641 | } | |
642 | ||
a0377dfe | 643 | LTTNG_ASSERT(type == LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE || |
a58c490f JG |
644 | type == LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE); |
645 | ||
646 | pthread_mutex_lock(&channel->lock); | |
647 | socket = channel->socket; | |
882093ee | 648 | |
a58c490f JG |
649 | if (!lttng_condition_validate(condition)) { |
650 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; | |
651 | goto end_unlock; | |
652 | } | |
653 | ||
c0a66c84 | 654 | ret = lttng_dynamic_buffer_append(&payload.buffer, &cmd_header, |
3647288f JG |
655 | sizeof(cmd_header)); |
656 | if (ret) { | |
657 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
a58c490f JG |
658 | goto end_unlock; |
659 | } | |
660 | ||
c0a66c84 | 661 | ret = lttng_condition_serialize(condition, &payload); |
3647288f JG |
662 | if (ret) { |
663 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; | |
a58c490f JG |
664 | goto end_unlock; |
665 | } | |
666 | ||
3647288f | 667 | /* Update payload length. */ |
c0a66c84 JG |
668 | ((struct lttng_notification_channel_message *) payload.buffer.data)->size = |
669 | (uint32_t) (payload.buffer.size - sizeof(cmd_header)); | |
3647288f | 670 | |
882093ee JR |
671 | { |
672 | struct lttng_payload_view pv = | |
673 | lttng_payload_view_from_payload( | |
674 | &payload, 0, -1); | |
675 | const int fd_count = | |
676 | lttng_payload_view_get_fd_handle_count(&pv); | |
677 | ||
678 | /* Update fd count. */ | |
679 | ((struct lttng_notification_channel_message *) payload.buffer.data)->fds = | |
680 | (uint32_t) fd_count; | |
681 | ||
682 | ret = lttcomm_send_unix_sock( | |
683 | socket, pv.buffer.data, pv.buffer.size); | |
684 | if (ret < 0) { | |
685 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
686 | goto end_unlock; | |
687 | } | |
688 | ||
689 | /* Pass fds if present. */ | |
690 | if (fd_count > 0) { | |
691 | ret = lttcomm_send_payload_view_fds_unix_sock(socket, | |
692 | &pv); | |
693 | if (ret < 0) { | |
694 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
695 | goto end_unlock; | |
696 | } | |
697 | } | |
a58c490f JG |
698 | } |
699 | ||
700 | ret = receive_command_reply(channel, &status); | |
701 | if (ret < 0) { | |
702 | status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; | |
703 | goto end_unlock; | |
704 | } | |
705 | end_unlock: | |
706 | pthread_mutex_unlock(&channel->lock); | |
707 | end: | |
c0a66c84 | 708 | lttng_payload_reset(&payload); |
a58c490f JG |
709 | return status; |
710 | } | |
711 | ||
712 | enum lttng_notification_channel_status lttng_notification_channel_subscribe( | |
713 | struct lttng_notification_channel *channel, | |
714 | const struct lttng_condition *condition) | |
715 | { | |
716 | return send_condition_command(channel, | |
717 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE, | |
718 | condition); | |
719 | } | |
720 | ||
721 | enum lttng_notification_channel_status lttng_notification_channel_unsubscribe( | |
722 | struct lttng_notification_channel *channel, | |
723 | const struct lttng_condition *condition) | |
724 | { | |
725 | return send_condition_command(channel, | |
726 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE, | |
727 | condition); | |
728 | } | |
729 | ||
730 | void lttng_notification_channel_destroy( | |
731 | struct lttng_notification_channel *channel) | |
732 | { | |
733 | if (!channel) { | |
734 | return; | |
735 | } | |
736 | ||
737 | if (channel->socket >= 0) { | |
738 | (void) lttcomm_close_unix_sock(channel->socket); | |
739 | } | |
740 | pthread_mutex_destroy(&channel->lock); | |
882093ee | 741 | lttng_payload_reset(&channel->reception_payload); |
a58c490f JG |
742 | free(channel); |
743 | } |