Fix: set the enable all event command type
[lttng-tools.git] / src / common / consumer.h
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1/*
2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * 2012 - David Goulet <dgoulet@efficios.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19
20#ifndef LIB_CONSUMER_H
21#define LIB_CONSUMER_H
22
23#include <limits.h>
24#include <poll.h>
25#include <unistd.h>
26#include <urcu/list.h>
27
28#include <lttng/lttng.h>
29
30#include <common/hashtable/hashtable.h>
31#include <common/compat/fcntl.h>
32#include <common/compat/uuid.h>
33#include <common/sessiond-comm/sessiond-comm.h>
34#include <common/pipe.h>
35#include <common/index/lttng-index.h>
36
37/* Commands for consumer */
38enum lttng_consumer_command {
39 LTTNG_CONSUMER_ADD_CHANNEL,
40 LTTNG_CONSUMER_ADD_STREAM,
41 /* pause, delete, active depending on fd state */
42 LTTNG_CONSUMER_UPDATE_STREAM,
43 /* inform the consumer to quit when all fd has hang up */
44 LTTNG_CONSUMER_STOP,
45 LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
46 /* Inform the consumer to kill a specific relayd connection */
47 LTTNG_CONSUMER_DESTROY_RELAYD,
48 /* Return to the sessiond if there is data pending for a session */
49 LTTNG_CONSUMER_DATA_PENDING,
50 /* Consumer creates a channel and returns it to sessiond. */
51 LTTNG_CONSUMER_ASK_CHANNEL_CREATION,
52 LTTNG_CONSUMER_GET_CHANNEL,
53 LTTNG_CONSUMER_DESTROY_CHANNEL,
54 LTTNG_CONSUMER_PUSH_METADATA,
55 LTTNG_CONSUMER_CLOSE_METADATA,
56 LTTNG_CONSUMER_SETUP_METADATA,
57 LTTNG_CONSUMER_FLUSH_CHANNEL,
58 LTTNG_CONSUMER_SNAPSHOT_CHANNEL,
59 LTTNG_CONSUMER_SNAPSHOT_METADATA,
60};
61
62/* State of each fd in consumer */
63enum lttng_consumer_stream_state {
64 LTTNG_CONSUMER_ACTIVE_STREAM,
65 LTTNG_CONSUMER_PAUSE_STREAM,
66 LTTNG_CONSUMER_DELETE_STREAM,
67};
68
69enum lttng_consumer_type {
70 LTTNG_CONSUMER_UNKNOWN = 0,
71 LTTNG_CONSUMER_KERNEL,
72 LTTNG_CONSUMER64_UST,
73 LTTNG_CONSUMER32_UST,
74};
75
76enum consumer_endpoint_status {
77 CONSUMER_ENDPOINT_ACTIVE,
78 CONSUMER_ENDPOINT_INACTIVE,
79};
80
81enum consumer_channel_output {
82 CONSUMER_CHANNEL_MMAP = 0,
83 CONSUMER_CHANNEL_SPLICE = 1,
84};
85
86enum consumer_channel_type {
87 CONSUMER_CHANNEL_TYPE_METADATA = 0,
88 CONSUMER_CHANNEL_TYPE_DATA = 1,
89};
90
91extern struct lttng_consumer_global_data consumer_data;
92
93struct stream_list {
94 struct cds_list_head head;
95 unsigned int count;
96};
97
98/* Stub. */
99struct consumer_metadata_cache;
100
101struct lttng_consumer_channel {
102 /* HT node used for consumer_data.channel_ht */
103 struct lttng_ht_node_u64 node;
104 /* Indexed key. Incremented value in the consumer. */
105 uint64_t key;
106 /* Number of streams referencing this channel */
107 int refcount;
108 /* Tracing session id on the session daemon side. */
109 uint64_t session_id;
110 /*
111 * Session id when requesting metadata to the session daemon for
112 * a session with per-PID buffers.
113 */
114 uint64_t session_id_per_pid;
115 /* Channel trace file path name. */
116 char pathname[PATH_MAX];
117 /* Channel name. */
118 char name[LTTNG_SYMBOL_NAME_LEN];
119 /* UID and GID of the session owning this channel. */
120 uid_t uid;
121 gid_t gid;
122 /* Relayd id of the channel. -1ULL if it does not apply. */
123 uint64_t relayd_id;
124 /*
125 * Number of streams NOT initialized yet. This is used in order to not
126 * delete this channel if streams are getting initialized.
127 */
128 unsigned int nb_init_stream_left;
129 /* Output type (mmap or splice). */
130 enum consumer_channel_output output;
131 /* Channel type for stream */
132 enum consumer_channel_type type;
133
134 /* For UST */
135 uid_t ust_app_uid; /* Application UID. */
136 struct ustctl_consumer_channel *uchan;
137 unsigned char uuid[UUID_STR_LEN];
138 /*
139 * Temporary stream list used to store the streams once created and waiting
140 * to be sent to the session daemon by receiving the
141 * LTTNG_CONSUMER_GET_CHANNEL.
142 */
143 struct stream_list streams;
144
145 /*
146 * Set if the channel is metadata. We keep a reference to the stream
147 * because we have to flush data once pushed by the session daemon. For a
148 * regular channel, this is always set to NULL.
149 */
150 struct lttng_consumer_stream *metadata_stream;
151
152 /* for UST */
153 int wait_fd;
154 /* Node within channel thread ht */
155 struct lttng_ht_node_u64 wait_fd_node;
156
157 /* Metadata cache is metadata channel */
158 struct consumer_metadata_cache *metadata_cache;
159 /* For UST metadata periodical flush */
160 int switch_timer_enabled;
161 timer_t switch_timer;
162 int switch_timer_error;
163
164 /* For the live mode */
165 int live_timer_enabled;
166 timer_t live_timer;
167 int live_timer_error;
168
169 /* On-disk circular buffer */
170 uint64_t tracefile_size;
171 uint64_t tracefile_count;
172 /*
173 * Monitor or not the streams of this channel meaning this indicates if the
174 * streams should be sent to the data/metadata thread or added to the no
175 * monitor list of the channel.
176 */
177 unsigned int monitor;
178
179 /*
180 * Channel lock.
181 *
182 * This lock protects against concurrent update of channel.
183 *
184 * This is nested INSIDE the consumer data lock.
185 * This is nested OUTSIDE the channel timer lock.
186 * This is nested OUTSIDE the metadata cache lock.
187 * This is nested OUTSIDE stream lock.
188 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
189 */
190 pthread_mutex_t lock;
191
192 /*
193 * Channel teardown lock.
194 *
195 * This lock protect against teardown of channel. It is _never_
196 * taken by the timer handler.
197 *
198 * This is nested INSIDE the consumer data lock.
199 * This is nested INSIDE the channel lock.
200 * This is nested OUTSIDE the metadata cache lock.
201 * This is nested OUTSIDE stream lock.
202 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
203 */
204 pthread_mutex_t timer_lock;
205
206 /* Timer value in usec for live streaming. */
207 unsigned int live_timer_interval;
208};
209
210/*
211 * Internal representation of the streams, sessiond_key is used to identify
212 * uniquely a stream.
213 */
214struct lttng_consumer_stream {
215 /* HT node used by the data_ht and metadata_ht */
216 struct lttng_ht_node_u64 node;
217 /* stream indexed per channel key node */
218 struct lttng_ht_node_u64 node_channel_id;
219 /* HT node used in consumer_data.stream_list_ht */
220 struct lttng_ht_node_u64 node_session_id;
221 /* Pointer to associated channel. */
222 struct lttng_consumer_channel *chan;
223
224 /* Key by which the stream is indexed for 'node'. */
225 uint64_t key;
226 /*
227 * File descriptor of the data output file. This can be either a file or a
228 * socket fd for relayd streaming.
229 */
230 int out_fd; /* output file to write the data */
231 /* Write position in the output file descriptor */
232 off_t out_fd_offset;
233 /* Amount of bytes written to the output */
234 uint64_t output_written;
235 enum lttng_consumer_stream_state state;
236 int shm_fd_is_copy;
237 int data_read;
238 int hangup_flush_done;
239 enum lttng_event_output output;
240 /* Maximum subbuffer size. */
241 unsigned long max_sb_size;
242
243 /*
244 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
245 * used for the mmap base and offset.
246 */
247 void *mmap_base;
248 unsigned long mmap_len;
249
250 /* For UST */
251
252 int wait_fd;
253 /* UID/GID of the user owning the session to which stream belongs */
254 uid_t uid;
255 gid_t gid;
256 /* Network sequence number. Indicating on which relayd socket it goes. */
257 uint64_t net_seq_idx;
258 /*
259 * Indicate if this stream was successfully sent to a relayd. This is set
260 * after the refcount of the relayd is incremented and is checked when the
261 * stream is closed before decrementing the refcount in order to avoid an
262 * unbalanced state.
263 */
264 unsigned int sent_to_relayd;
265
266 /* Identify if the stream is the metadata */
267 unsigned int metadata_flag;
268 /* Used when the stream is set for network streaming */
269 uint64_t relayd_stream_id;
270 /*
271 * When sending a stream packet to a relayd, this number is used to track
272 * the packet sent by the consumer and seen by the relayd. When sending the
273 * data header to the relayd, this number is sent and if the transmission
274 * was successful, it is incremented.
275 *
276 * Even if the full data is not fully transmitted it won't matter since
277 * only two possible error can happen after that where either the relayd
278 * died or a read error is detected on the stream making this value useless
279 * after that.
280 *
281 * This value SHOULD be read/updated atomically or with the lock acquired.
282 */
283 uint64_t next_net_seq_num;
284 /*
285 * Lock to use the stream FDs since they are used between threads.
286 *
287 * This is nested INSIDE the consumer_data lock.
288 * This is nested INSIDE the metadata cache lock.
289 * This is nested INSIDE the channel lock.
290 * This is nested INSIDE the channel timer lock.
291 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
292 */
293 pthread_mutex_t lock;
294 /* Tracing session id */
295 uint64_t session_id;
296 /*
297 * Indicates if the stream end point is still active or not (network
298 * streaming or local file system). The thread "owning" the stream is
299 * handling this status and can be notified of a state change through the
300 * consumer data appropriate pipe.
301 */
302 enum consumer_endpoint_status endpoint_status;
303 /* Stream name. Format is: <channel_name>_<cpu_number> */
304 char name[LTTNG_SYMBOL_NAME_LEN];
305 /* Internal state of libustctl. */
306 struct ustctl_consumer_stream *ustream;
307 struct cds_list_head send_node;
308 /* On-disk circular buffer */
309 uint64_t tracefile_size_current;
310 uint64_t tracefile_count_current;
311 /*
312 * Monitor or not the streams of this channel meaning this indicates if the
313 * streams should be sent to the data/metadata thread or added to the no
314 * monitor list of the channel.
315 */
316 unsigned int monitor;
317 /*
318 * Indicate if the stream is globally visible meaning that it has been
319 * added to the multiple hash tables. If *not* set, NO lock should be
320 * acquired in the destroy path.
321 */
322 unsigned int globally_visible;
323 /*
324 * Pipe to wake up the metadata poll thread when the UST metadata
325 * cache is updated.
326 */
327 int ust_metadata_poll_pipe[2];
328 /*
329 * How much metadata was read from the metadata cache and sent
330 * to the channel.
331 */
332 uint64_t ust_metadata_pushed;
333 /*
334 * FD of the index file for this stream.
335 */
336 int index_fd;
337
338 /*
339 * Rendez-vous point between data and metadata stream in live mode.
340 */
341 pthread_cond_t metadata_rdv;
342 pthread_mutex_t metadata_rdv_lock;
343};
344
345/*
346 * Internal representation of a relayd socket pair.
347 */
348struct consumer_relayd_sock_pair {
349 /* Network sequence number. */
350 uint64_t net_seq_idx;
351 /* Number of stream associated with this relayd */
352 unsigned int refcount;
353
354 /*
355 * This flag indicates whether or not we should destroy this object. The
356 * destruction should ONLY occurs when this flag is set and the refcount is
357 * set to zero.
358 */
359 unsigned int destroy_flag;
360
361 /*
362 * Mutex protecting the control socket to avoid out of order packets
363 * between threads sending data to the relayd. Since metadata data is sent
364 * over that socket, at least two sendmsg() are needed (header + data)
365 * creating a race for packets to overlap between threads using it.
366 *
367 * This is nested INSIDE the consumer_data lock.
368 * This is nested INSIDE the stream lock.
369 */
370 pthread_mutex_t ctrl_sock_mutex;
371
372 /* Control socket. Command and metadata are passed over it */
373 struct lttcomm_relayd_sock control_sock;
374
375 /*
376 * We don't need a mutex at this point since we only splice or write single
377 * large chunk of data with a header appended at the begining. Moreover,
378 * this socket is for now only used in a single thread.
379 */
380 struct lttcomm_relayd_sock data_sock;
381 struct lttng_ht_node_u64 node;
382
383 /* Session id on both sides for the sockets. */
384 uint64_t relayd_session_id;
385 uint64_t sessiond_session_id;
386};
387
388/*
389 * UST consumer local data to the program. One or more instance per
390 * process.
391 */
392struct lttng_consumer_local_data {
393 /*
394 * Function to call when data is available on a buffer.
395 * Returns the number of bytes read, or negative error value.
396 */
397 ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
398 struct lttng_consumer_local_data *ctx);
399 /*
400 * function to call when we receive a new channel, it receives a
401 * newly allocated channel, depending on the return code of this
402 * function, the new channel will be handled by the application
403 * or the library.
404 *
405 * Returns:
406 * > 0 (success, FD is kept by application)
407 * == 0 (success, FD is left to library)
408 * < 0 (error)
409 */
410 int (*on_recv_channel)(struct lttng_consumer_channel *channel);
411 /*
412 * function to call when we receive a new stream, it receives a
413 * newly allocated stream, depending on the return code of this
414 * function, the new stream will be handled by the application
415 * or the library.
416 *
417 * Returns:
418 * > 0 (success, FD is kept by application)
419 * == 0 (success, FD is left to library)
420 * < 0 (error)
421 */
422 int (*on_recv_stream)(struct lttng_consumer_stream *stream);
423 /*
424 * function to call when a stream is getting updated by the session
425 * daemon, this function receives the sessiond key and the new
426 * state, depending on the return code of this function the
427 * update of state for the stream is handled by the application
428 * or the library.
429 *
430 * Returns:
431 * > 0 (success, FD is kept by application)
432 * == 0 (success, FD is left to library)
433 * < 0 (error)
434 */
435 int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
436 enum lttng_consumer_type type;
437 /* socket to communicate errors with sessiond */
438 int consumer_error_socket;
439 /* socket to ask metadata to sessiond. */
440 int consumer_metadata_socket;
441 /*
442 * Protect consumer_metadata_socket.
443 *
444 * This is nested OUTSIDE the metadata cache lock.
445 */
446 pthread_mutex_t metadata_socket_lock;
447 /* socket to exchange commands with sessiond */
448 char *consumer_command_sock_path;
449 /* communication with splice */
450 int consumer_thread_pipe[2];
451 int consumer_channel_pipe[2];
452 int consumer_splice_metadata_pipe[2];
453 /* Data stream poll thread pipe. To transfer data stream to the thread */
454 struct lttng_pipe *consumer_data_pipe;
455 /* to let the signal handler wake up the fd receiver thread */
456 int consumer_should_quit[2];
457 /* Metadata poll thread pipe. Transfer metadata stream to it */
458 struct lttng_pipe *consumer_metadata_pipe;
459};
460
461/*
462 * Library-level data. One instance per process.
463 */
464struct lttng_consumer_global_data {
465 /*
466 * At this time, this lock is used to ensure coherence between the count
467 * and number of element in the hash table. It's also a protection for
468 * concurrent read/write between threads.
469 *
470 * This is nested OUTSIDE the stream lock.
471 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
472 */
473 pthread_mutex_t lock;
474
475 /*
476 * Number of streams in the data stream hash table declared outside.
477 * Protected by consumer_data.lock.
478 */
479 int stream_count;
480
481 /* Channel hash table protected by consumer_data.lock. */
482 struct lttng_ht *channel_ht;
483 /*
484 * Flag specifying if the local array of FDs needs update in the
485 * poll function. Protected by consumer_data.lock.
486 */
487 unsigned int need_update;
488 enum lttng_consumer_type type;
489
490 /*
491 * Relayd socket(s) hashtable indexed by network sequence number. Each
492 * stream has an index which associate the right relayd socket to use.
493 */
494 struct lttng_ht *relayd_ht;
495
496 /*
497 * This hash table contains all streams (metadata and data) indexed by
498 * session id. In other words, the ht is indexed by session id and each
499 * bucket contains the list of associated streams.
500 *
501 * This HT uses the "node_session_id" of the consumer stream.
502 */
503 struct lttng_ht *stream_list_ht;
504
505 /*
506 * This HT uses the "node_channel_id" of the consumer stream.
507 */
508 struct lttng_ht *stream_per_chan_id_ht;
509};
510
511/*
512 * Init consumer data structures.
513 */
514void lttng_consumer_init(void);
515
516/*
517 * Set the error socket for communication with a session daemon.
518 */
519void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
520 int sock);
521
522/*
523 * Set the command socket path for communication with a session daemon.
524 */
525void lttng_consumer_set_command_sock_path(
526 struct lttng_consumer_local_data *ctx, char *sock);
527
528/*
529 * Send return code to session daemon.
530 *
531 * Returns the return code of sendmsg : the number of bytes transmitted or -1
532 * on error.
533 */
534int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
535
536/*
537 * Called from signal handler to ensure a clean exit.
538 */
539void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
540
541/*
542 * Cleanup the daemon's socket on exit.
543 */
544void lttng_consumer_cleanup(void);
545
546/*
547 * Flush pending writes to trace output disk file.
548 */
549void lttng_consumer_sync_trace_file(struct lttng_consumer_stream *stream,
550 off_t orig_offset);
551
552/*
553 * Poll on the should_quit pipe and the command socket return -1 on error and
554 * should exit, 0 if data is available on the command socket
555 */
556int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
557
558struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
559 uint64_t stream_key,
560 enum lttng_consumer_stream_state state,
561 const char *channel_name,
562 uid_t uid,
563 gid_t gid,
564 uint64_t relayd_id,
565 uint64_t session_id,
566 int cpu,
567 int *alloc_ret,
568 enum consumer_channel_type type,
569 unsigned int monitor);
570struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
571 uint64_t session_id,
572 const char *pathname,
573 const char *name,
574 uid_t uid,
575 gid_t gid,
576 uint64_t relayd_id,
577 enum lttng_event_output output,
578 uint64_t tracefile_size,
579 uint64_t tracefile_count,
580 uint64_t session_id_per_pid,
581 unsigned int monitor,
582 unsigned int live_timer_interval);
583void consumer_del_stream(struct lttng_consumer_stream *stream,
584 struct lttng_ht *ht);
585void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
586 struct lttng_ht *ht);
587int consumer_add_channel(struct lttng_consumer_channel *channel,
588 struct lttng_consumer_local_data *ctx);
589void consumer_del_channel(struct lttng_consumer_channel *channel);
590
591/* lttng-relayd consumer command */
592struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair(
593 uint64_t net_seq_idx);
594struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
595int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
596void close_relayd_stream(struct lttng_consumer_stream *stream);
597struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
598int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
599 size_t data_size);
600void consumer_steal_stream_key(int key, struct lttng_ht *ht);
601
602struct lttng_consumer_local_data *lttng_consumer_create(
603 enum lttng_consumer_type type,
604 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
605 struct lttng_consumer_local_data *ctx),
606 int (*recv_channel)(struct lttng_consumer_channel *channel),
607 int (*recv_stream)(struct lttng_consumer_stream *stream),
608 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
609void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
610ssize_t lttng_consumer_on_read_subbuffer_mmap(
611 struct lttng_consumer_local_data *ctx,
612 struct lttng_consumer_stream *stream, unsigned long len,
613 unsigned long padding,
614 struct lttng_packet_index *index);
615ssize_t lttng_consumer_on_read_subbuffer_splice(
616 struct lttng_consumer_local_data *ctx,
617 struct lttng_consumer_stream *stream, unsigned long len,
618 unsigned long padding,
619 struct lttng_packet_index *index);
620int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
621int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
622 unsigned long *pos);
623void *consumer_thread_metadata_poll(void *data);
624void *consumer_thread_data_poll(void *data);
625void *consumer_thread_sessiond_poll(void *data);
626void *consumer_thread_channel_poll(void *data);
627int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
628 int sock, struct pollfd *consumer_sockpoll);
629
630ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
631 struct lttng_consumer_local_data *ctx);
632int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
633int consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
634 struct lttng_consumer_local_data *ctx, int sock,
635 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
636 uint64_t sessiond_id, uint64_t relayd_session_id);
637void consumer_flag_relayd_for_destroy(
638 struct consumer_relayd_sock_pair *relayd);
639int consumer_data_pending(uint64_t id);
640int consumer_send_status_msg(int sock, int ret_code);
641int consumer_send_status_channel(int sock,
642 struct lttng_consumer_channel *channel);
643void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
644 uint64_t key);
645void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
646unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos,
647 unsigned long produced_pos, uint64_t max_stream_size);
648int consumer_add_data_stream(struct lttng_consumer_stream *stream);
649void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
650int consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
651void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
652int consumer_create_index_file(struct lttng_consumer_stream *stream);
653
654#endif /* LIB_CONSUMER_H */
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