Commit | Line | Data |
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d4a1283e JD |
1 | /* |
2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> | |
3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License | |
7 | * as published by the Free Software Foundation; either version 2 | |
8 | * of the License, or (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
18 | */ | |
19 | ||
20 | #define _GNU_SOURCE | |
21 | #include <fcntl.h> | |
22 | #include <getopt.h> | |
23 | #include <grp.h> | |
24 | #include <limits.h> | |
25 | #include <pthread.h> | |
26 | #include <signal.h> | |
27 | #include <stdio.h> | |
28 | #include <stdlib.h> | |
29 | #include <string.h> | |
30 | #include <sys/ipc.h> | |
31 | #include <sys/shm.h> | |
32 | #include <sys/socket.h> | |
33 | #include <sys/stat.h> | |
34 | #include <sys/types.h> | |
35 | #include <urcu/list.h> | |
36 | #include <poll.h> | |
37 | #include <unistd.h> | |
38 | ||
39 | #include "lttngerr.h" | |
40 | #include "libkernelctl.h" | |
41 | #include "liblttsessiondcomm.h" | |
42 | #include "kconsumerd.h" | |
43 | ||
44 | /* Init the list of FDs */ | |
45 | static struct ltt_kconsumerd_fd_list kconsumerd_fd_list = { | |
46 | .head = CDS_LIST_HEAD_INIT(kconsumerd_fd_list.head), | |
47 | }; | |
48 | ||
49 | /* Number of element for the list below. */ | |
50 | static unsigned int fds_count; | |
51 | ||
52 | /* If the local array of FDs needs update in the poll function */ | |
53 | static unsigned int update_fd_array = 1; | |
54 | ||
55 | /* lock the fd array and structures */ | |
56 | static pthread_mutex_t kconsumerd_lock_fds; | |
57 | ||
58 | /* the two threads (receive fd and poll) */ | |
59 | static pthread_t threads[2]; | |
60 | ||
61 | /* communication with splice */ | |
62 | static int thread_pipe[2]; | |
63 | ||
252fd492 JD |
64 | /* pipe to wake the poll thread when necessary */ |
65 | static int poll_pipe[2]; | |
66 | ||
d4a1283e JD |
67 | /* socket to communicate errors with sessiond */ |
68 | static int error_socket = -1; | |
69 | ||
13e44745 JD |
70 | /* to count the number of time the user pressed ctrl+c */ |
71 | static int sigintcount = 0; | |
72 | ||
d4a1283e JD |
73 | /* Argument variables */ |
74 | int opt_quiet; | |
75 | int opt_verbose; | |
76 | static int opt_daemon; | |
77 | static const char *progname; | |
78 | static char command_sock_path[PATH_MAX]; /* Global command socket path */ | |
79 | static char error_sock_path[PATH_MAX]; /* Global error path */ | |
80 | ||
bcd8d9db JD |
81 | /* |
82 | * del_fd | |
83 | * | |
84 | * Remove a fd from the global list protected by a mutex | |
85 | */ | |
86 | static void del_fd(struct ltt_kconsumerd_fd *lcf) | |
87 | { | |
6aea26bc | 88 | DBG("Removing %d", lcf->consumerd_fd); |
bcd8d9db JD |
89 | pthread_mutex_lock(&kconsumerd_lock_fds); |
90 | cds_list_del(&lcf->list); | |
91 | if (fds_count > 0) { | |
92 | fds_count--; | |
93 | DBG("Removed ltt_kconsumerd_fd"); | |
94 | if (lcf != NULL) { | |
95 | close(lcf->out_fd); | |
96 | close(lcf->consumerd_fd); | |
97 | free(lcf); | |
98 | lcf = NULL; | |
99 | } | |
100 | } | |
101 | pthread_mutex_unlock(&kconsumerd_lock_fds); | |
102 | } | |
103 | ||
d4a1283e JD |
104 | /* |
105 | * cleanup | |
106 | * | |
107 | * Cleanup the daemon's socket on exit | |
108 | */ | |
109 | static void cleanup() | |
110 | { | |
bcd8d9db JD |
111 | struct ltt_kconsumerd_fd *iter; |
112 | ||
bcd8d9db | 113 | /* remove the socket file */ |
d4a1283e | 114 | unlink(command_sock_path); |
bcd8d9db JD |
115 | |
116 | /* unblock the threads */ | |
117 | WARN("Terminating the threads before exiting"); | |
118 | pthread_cancel(threads[0]); | |
119 | pthread_cancel(threads[1]); | |
120 | ||
121 | /* close all outfd */ | |
122 | cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) { | |
123 | del_fd(iter); | |
124 | } | |
d4a1283e JD |
125 | } |
126 | ||
6aea26bc JD |
127 | /* |
128 | * send_error | |
d4a1283e JD |
129 | * |
130 | * send return code to ltt-sessiond | |
131 | */ | |
132 | static int send_error(enum lttcomm_return_code cmd) | |
133 | { | |
134 | if (error_socket > 0) { | |
135 | return lttcomm_send_unix_sock(error_socket, &cmd, | |
136 | sizeof(enum lttcomm_sessiond_command)); | |
137 | } else { | |
138 | return 0; | |
139 | } | |
140 | } | |
141 | ||
d4a1283e JD |
142 | /* |
143 | * add_fd | |
144 | * | |
145 | * Add a fd to the global list protected by a mutex | |
146 | */ | |
147 | static int add_fd(struct lttcomm_kconsumerd_msg *buf, int consumerd_fd) | |
148 | { | |
149 | struct ltt_kconsumerd_fd *tmp_fd; | |
150 | int ret; | |
151 | ||
152 | tmp_fd = malloc(sizeof(struct ltt_kconsumerd_fd)); | |
153 | tmp_fd->sessiond_fd = buf->fd; | |
154 | tmp_fd->consumerd_fd = consumerd_fd; | |
155 | tmp_fd->state = buf->state; | |
156 | tmp_fd->max_sb_size = buf->max_sb_size; | |
157 | strncpy(tmp_fd->path_name, buf->path_name, PATH_MAX); | |
158 | ||
159 | /* Opening the tracefile in write mode */ | |
160 | DBG("Opening %s for writing", tmp_fd->path_name); | |
161 | ret = open(tmp_fd->path_name, | |
46258765 | 162 | O_WRONLY|O_CREAT|O_TRUNC, S_IRWXU|S_IRWXG|S_IRWXO); |
d4a1283e JD |
163 | if (ret < 0) { |
164 | ERR("Opening %s", tmp_fd->path_name); | |
165 | perror("open"); | |
166 | goto end; | |
167 | } | |
168 | tmp_fd->out_fd = ret; | |
169 | tmp_fd->out_fd_offset = 0; | |
170 | ||
171 | DBG("Adding %s (%d, %d, %d)", tmp_fd->path_name, | |
172 | tmp_fd->sessiond_fd, tmp_fd->consumerd_fd, tmp_fd->out_fd); | |
173 | ||
174 | pthread_mutex_lock(&kconsumerd_lock_fds); | |
175 | cds_list_add(&tmp_fd->list, &kconsumerd_fd_list.head); | |
176 | fds_count++; | |
177 | pthread_mutex_unlock(&kconsumerd_lock_fds); | |
178 | ||
179 | end: | |
180 | return ret; | |
181 | } | |
182 | ||
d4a1283e JD |
183 | |
184 | /* | |
185 | * sighandler | |
186 | * | |
187 | * Signal handler for the daemon | |
188 | */ | |
189 | static void sighandler(int sig) | |
190 | { | |
13e44745 JD |
191 | if (sig == SIGINT && sigintcount++ == 0) { |
192 | DBG("ignoring first SIGINT"); | |
193 | return; | |
194 | } | |
195 | ||
d4a1283e JD |
196 | cleanup(); |
197 | ||
198 | return; | |
199 | } | |
200 | ||
201 | /* | |
202 | * set_signal_handler | |
203 | * | |
204 | * Setup signal handler for : | |
205 | * SIGINT, SIGTERM, SIGPIPE | |
206 | */ | |
207 | static int set_signal_handler(void) | |
208 | { | |
209 | int ret = 0; | |
210 | struct sigaction sa; | |
211 | sigset_t sigset; | |
212 | ||
213 | if ((ret = sigemptyset(&sigset)) < 0) { | |
214 | perror("sigemptyset"); | |
215 | return ret; | |
216 | } | |
217 | ||
218 | sa.sa_handler = sighandler; | |
219 | sa.sa_mask = sigset; | |
220 | sa.sa_flags = 0; | |
221 | if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { | |
222 | perror("sigaction"); | |
223 | return ret; | |
224 | } | |
225 | ||
226 | if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { | |
227 | perror("sigaction"); | |
228 | return ret; | |
229 | } | |
230 | ||
231 | if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) { | |
232 | perror("sigaction"); | |
233 | return ret; | |
234 | } | |
235 | ||
236 | return ret; | |
237 | } | |
238 | ||
239 | /* | |
240 | * on_read_subbuffer | |
241 | * | |
242 | * Splice the data from the ring buffer to the tracefile. | |
243 | * Returns the number of bytes spliced | |
244 | */ | |
245 | static int on_read_subbuffer(struct ltt_kconsumerd_fd *kconsumerd_fd, | |
246 | unsigned long len) | |
247 | { | |
248 | long ret = 0; | |
249 | loff_t offset = 0; | |
250 | off_t orig_offset = kconsumerd_fd->out_fd_offset; | |
251 | int fd = kconsumerd_fd->consumerd_fd; | |
252 | int outfd = kconsumerd_fd->out_fd; | |
253 | ||
254 | while (len > 0) { | |
255 | DBG("splice chan to pipe offset %lu (fd : %d)", | |
256 | (unsigned long)offset, fd); | |
257 | ret = splice(fd, &offset, thread_pipe[1], NULL, len, | |
258 | SPLICE_F_MOVE | SPLICE_F_MORE); | |
259 | DBG("splice chan to pipe ret %ld", ret); | |
260 | if (ret < 0) { | |
0632499a | 261 | ret = errno; |
d4a1283e | 262 | perror("Error in relay splice"); |
0632499a | 263 | goto splice_error; |
d4a1283e JD |
264 | } |
265 | ||
266 | ret = splice(thread_pipe[0], NULL, outfd, NULL, ret, | |
267 | SPLICE_F_MOVE | SPLICE_F_MORE); | |
268 | DBG("splice pipe to file %ld", ret); | |
269 | if (ret < 0) { | |
0632499a | 270 | ret = errno; |
d4a1283e | 271 | perror("Error in file splice"); |
0632499a | 272 | goto splice_error; |
d4a1283e JD |
273 | } |
274 | if (ret >= len) { | |
275 | len = 0; | |
276 | } | |
277 | /* This won't block, but will start writeout asynchronously */ | |
278 | sync_file_range(outfd, kconsumerd_fd->out_fd_offset, ret, | |
279 | SYNC_FILE_RANGE_WRITE); | |
280 | kconsumerd_fd->out_fd_offset += ret; | |
281 | } | |
0632499a | 282 | |
d4a1283e JD |
283 | /* |
284 | * This does a blocking write-and-wait on any page that belongs to the | |
285 | * subbuffer prior to the one we just wrote. | |
286 | * Don't care about error values, as these are just hints and ways to | |
287 | * limit the amount of page cache used. | |
288 | */ | |
289 | if (orig_offset >= kconsumerd_fd->max_sb_size) { | |
290 | sync_file_range(outfd, orig_offset - kconsumerd_fd->max_sb_size, | |
291 | kconsumerd_fd->max_sb_size, | |
292 | SYNC_FILE_RANGE_WAIT_BEFORE | |
293 | | SYNC_FILE_RANGE_WRITE | |
294 | | SYNC_FILE_RANGE_WAIT_AFTER); | |
295 | /* | |
296 | * Give hints to the kernel about how we access the file: | |
297 | * POSIX_FADV_DONTNEED : we won't re-access data in a near | |
298 | * future after we write it. | |
299 | * We need to call fadvise again after the file grows because | |
300 | * the kernel does not seem to apply fadvise to non-existing | |
301 | * parts of the file. | |
302 | * Call fadvise _after_ having waited for the page writeback to | |
303 | * complete because the dirty page writeback semantic is not | |
304 | * well defined. So it can be expected to lead to lower | |
305 | * throughput in streaming. | |
306 | */ | |
307 | posix_fadvise(outfd, orig_offset - kconsumerd_fd->max_sb_size, | |
308 | kconsumerd_fd->max_sb_size, POSIX_FADV_DONTNEED); | |
309 | } | |
0632499a JD |
310 | goto end; |
311 | ||
312 | splice_error: | |
313 | /* send the appropriate error description to sessiond */ | |
314 | switch(ret) { | |
914a571b JD |
315 | case EBADF: |
316 | send_error(KCONSUMERD_SPLICE_EBADF); | |
317 | break; | |
318 | case EINVAL: | |
319 | send_error(KCONSUMERD_SPLICE_EINVAL); | |
320 | break; | |
321 | case ENOMEM: | |
322 | send_error(KCONSUMERD_SPLICE_ENOMEM); | |
323 | break; | |
324 | case ESPIPE: | |
325 | send_error(KCONSUMERD_SPLICE_ESPIPE); | |
326 | break; | |
0632499a JD |
327 | } |
328 | ||
329 | end: | |
d4a1283e JD |
330 | return ret; |
331 | } | |
332 | ||
333 | /* | |
334 | * read_subbuffer | |
335 | * | |
336 | * Consume data on a file descriptor and write it on a trace file | |
337 | */ | |
338 | static int read_subbuffer(struct ltt_kconsumerd_fd *kconsumerd_fd) | |
339 | { | |
340 | unsigned long len; | |
341 | int err; | |
342 | long ret = 0; | |
343 | int infd = kconsumerd_fd->consumerd_fd; | |
344 | ||
6aea26bc | 345 | DBG("In read_subbuffer (infd : %d)", infd); |
d4a1283e JD |
346 | /* Get the next subbuffer */ |
347 | err = kernctl_get_next_subbuf(infd); | |
348 | if (err != 0) { | |
349 | ret = errno; | |
350 | perror("Reserving sub buffer failed (everything is normal, " | |
351 | "it is due to concurrency)"); | |
352 | goto end; | |
353 | } | |
354 | ||
355 | /* read the whole subbuffer */ | |
356 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
357 | if (err != 0) { | |
358 | ret = errno; | |
359 | perror("Getting sub-buffer len failed."); | |
360 | goto end; | |
361 | } | |
362 | ||
363 | /* splice the subbuffer to the tracefile */ | |
364 | ret = on_read_subbuffer(kconsumerd_fd, len); | |
365 | if (ret < 0) { | |
366 | /* | |
367 | * display the error but continue processing to try | |
368 | * to release the subbuffer | |
369 | */ | |
370 | ERR("Error splicing to tracefile"); | |
371 | } | |
372 | ||
373 | err = kernctl_put_next_subbuf(infd); | |
374 | if (err != 0) { | |
375 | ret = errno; | |
376 | if (errno == EFAULT) { | |
377 | perror("Error in unreserving sub buffer\n"); | |
378 | } else if (errno == EIO) { | |
379 | /* Should never happen with newer LTTng versions */ | |
380 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
381 | } | |
382 | goto end; | |
383 | } | |
384 | ||
385 | end: | |
386 | return ret; | |
387 | } | |
388 | ||
389 | /* | |
390 | * change_fd_state | |
391 | * | |
392 | * Update a fd according to what we just received | |
393 | */ | |
394 | static void change_fd_state(int sessiond_fd, | |
5dc18550 | 395 | enum kconsumerd_fd_state state) |
d4a1283e JD |
396 | { |
397 | struct ltt_kconsumerd_fd *iter; | |
398 | cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) { | |
399 | if (iter->sessiond_fd == sessiond_fd) { | |
400 | iter->state = state; | |
401 | break; | |
402 | } | |
403 | } | |
404 | } | |
405 | ||
406 | /* | |
407 | * consumerd_recv_fd | |
408 | * | |
409 | * Receives an array of file descriptors and the associated | |
410 | * structures describing each fd (path name). | |
411 | * Returns the size of received data | |
412 | */ | |
413 | static int consumerd_recv_fd(int sfd, int size, | |
5dc18550 | 414 | enum kconsumerd_command cmd_type) |
d4a1283e JD |
415 | { |
416 | struct msghdr msg; | |
417 | struct iovec iov[1]; | |
252fd492 | 418 | int ret, i, tmp2; |
d4a1283e JD |
419 | struct cmsghdr *cmsg; |
420 | int nb_fd; | |
421 | char tmp[CMSG_SPACE(size)]; | |
422 | struct lttcomm_kconsumerd_msg *buf; | |
423 | /* the number of fds we are about to receive */ | |
424 | nb_fd = size/sizeof(struct lttcomm_kconsumerd_msg); | |
425 | ||
426 | buf = malloc(size); | |
427 | ||
428 | memset(&msg, 0, sizeof(msg)); | |
429 | ||
430 | /* Prepare to receive the structures */ | |
431 | iov[0].iov_base = buf; | |
432 | iov[0].iov_len = size; | |
433 | msg.msg_iov = iov; | |
434 | msg.msg_iovlen = 1; | |
435 | ||
436 | msg.msg_control = tmp; | |
437 | msg.msg_controllen = sizeof(tmp); | |
438 | ||
439 | DBG("Waiting to receive fds"); | |
440 | if ((ret = recvmsg(sfd, &msg, 0)) < 0) { | |
441 | perror("recvmsg"); | |
442 | } | |
443 | if (ret != size) { | |
444 | ERR("Received only %d, expected %d", ret, size); | |
445 | send_error(KCONSUMERD_ERROR_RECV_FD); | |
446 | goto end; | |
447 | } | |
448 | ||
449 | cmsg = CMSG_FIRSTHDR(&msg); | |
450 | if (!cmsg) { | |
451 | ERR("Invalid control message header"); | |
452 | ret = -1; | |
453 | send_error(KCONSUMERD_ERROR_RECV_FD); | |
454 | goto end; | |
455 | } | |
456 | ||
457 | /* if we received fds */ | |
458 | if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { | |
459 | DBG("Receive : expecting %d fds", nb_fd); | |
460 | for (i = 0; i < nb_fd; i++) { | |
461 | switch (cmd_type) { | |
5dc18550 | 462 | case ADD_STREAM: |
914a571b JD |
463 | DBG("add_fd %s (%d)", buf[i].path_name, ((int *)CMSG_DATA(cmsg))[i]); |
464 | ret = add_fd(&buf[i], ((int *)CMSG_DATA(cmsg))[i]); | |
465 | if (ret < 0) { | |
466 | send_error(KCONSUMERD_OUTFD_ERROR); | |
467 | goto end; | |
468 | } | |
469 | break; | |
5dc18550 | 470 | case UPDATE_STREAM: |
914a571b JD |
471 | change_fd_state(buf[i].fd, buf[i].state); |
472 | break; | |
473 | default: | |
474 | break; | |
d4a1283e JD |
475 | } |
476 | } | |
477 | /* flag to tell the polling thread to update its fd array */ | |
478 | update_fd_array = 1; | |
252fd492 JD |
479 | /* signal the poll thread */ |
480 | tmp2 = write(poll_pipe[1], "4", 1); | |
d4a1283e JD |
481 | } else { |
482 | ERR("Didn't received any fd"); | |
483 | send_error(KCONSUMERD_ERROR_RECV_FD); | |
484 | ret = -1; | |
485 | goto end; | |
486 | } | |
487 | ||
488 | end: | |
489 | if (buf != NULL) { | |
490 | free(buf); | |
491 | buf = NULL; | |
492 | } | |
493 | return ret; | |
494 | } | |
495 | ||
496 | /* | |
497 | * thread_receive_fds | |
498 | * | |
499 | * This thread listens on the consumerd socket and | |
500 | * receives the file descriptors from ltt-sessiond | |
501 | */ | |
502 | static void *thread_receive_fds(void *data) | |
503 | { | |
504 | int sock, client_socket, ret; | |
505 | struct lttcomm_kconsumerd_header tmp; | |
506 | ||
507 | DBG("Creating command socket %s", command_sock_path); | |
508 | unlink(command_sock_path); | |
509 | client_socket = lttcomm_create_unix_sock(command_sock_path); | |
510 | if (client_socket < 0) { | |
511 | ERR("Cannot create command socket"); | |
512 | goto error; | |
513 | } | |
514 | ||
515 | ret = lttcomm_listen_unix_sock(client_socket); | |
516 | if (ret < 0) { | |
517 | goto error; | |
518 | } | |
519 | ||
520 | DBG("Sending ready command to ltt-sessiond"); | |
521 | ret = send_error(KCONSUMERD_COMMAND_SOCK_READY); | |
522 | if (ret < 0) { | |
523 | ERR("Error sending ready command to ltt-sessiond"); | |
524 | goto error; | |
525 | } | |
526 | ||
7e8c38c6 JD |
527 | /* Blocking call, waiting for transmission */ |
528 | sock = lttcomm_accept_unix_sock(client_socket); | |
529 | if (sock <= 0) { | |
4abc0780 | 530 | WARN("On accept"); |
7e8c38c6 JD |
531 | goto error; |
532 | } | |
d4a1283e | 533 | while (1) { |
d4a1283e JD |
534 | /* We first get the number of fd we are about to receive */ |
535 | ret = lttcomm_recv_unix_sock(sock, &tmp, | |
536 | sizeof(struct lttcomm_kconsumerd_header)); | |
6aea26bc | 537 | if (ret <= 0) { |
bcd8d9db JD |
538 | ERR("Receiving the lttcomm_kconsumerd_header, exiting"); |
539 | goto error; | |
d4a1283e JD |
540 | } |
541 | ret = consumerd_recv_fd(sock, tmp.payload_size, tmp.cmd_type); | |
6aea26bc | 542 | if (ret <= 0) { |
bcd8d9db JD |
543 | ERR("Receiving the FD, exiting"); |
544 | goto error; | |
d4a1283e JD |
545 | } |
546 | } | |
547 | ||
548 | error: | |
549 | return NULL; | |
550 | } | |
551 | ||
552 | /* | |
553 | * update_poll_array | |
554 | * | |
555 | * Allocate the pollfd structure and the local view of the out fds | |
556 | * to avoid doing a lookup in the linked list and concurrency issues | |
557 | * when writing is needed. | |
558 | * Returns the number of fds in the structures | |
559 | */ | |
560 | static int update_poll_array(struct pollfd **pollfd, | |
561 | struct ltt_kconsumerd_fd **local_kconsumerd_fd) | |
562 | { | |
563 | struct ltt_kconsumerd_fd *iter; | |
564 | int i = 0; | |
565 | ||
d4a1283e JD |
566 | |
567 | DBG("Updating poll fd array"); | |
568 | pthread_mutex_lock(&kconsumerd_lock_fds); | |
569 | ||
570 | cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) { | |
571 | DBG("Inside for each"); | |
572 | if (iter->state == ACTIVE_FD) { | |
573 | DBG("Active FD %d", iter->consumerd_fd); | |
1b686c3f JD |
574 | (*pollfd)[i].fd = iter->consumerd_fd; |
575 | (*pollfd)[i].events = POLLIN | POLLPRI; | |
d4a1283e JD |
576 | local_kconsumerd_fd[i] = iter; |
577 | i++; | |
578 | } else if (iter->state == DELETE_FD) { | |
579 | del_fd(iter); | |
580 | } | |
581 | } | |
252fd492 JD |
582 | /* |
583 | * insert the poll_pipe at the end of the array and don't increment i | |
584 | * so nb_fd is the number of real FD | |
585 | */ | |
586 | (*pollfd)[i].fd = poll_pipe[0]; | |
587 | (*pollfd)[i].events = POLLIN; | |
588 | ||
d4a1283e JD |
589 | update_fd_array = 0; |
590 | pthread_mutex_unlock(&kconsumerd_lock_fds); | |
591 | return i; | |
592 | ||
d4a1283e JD |
593 | } |
594 | ||
595 | /* | |
596 | * thread_poll_fds | |
597 | * | |
598 | * This thread polls the fds in the ltt_fd_list to consume the data | |
599 | * and write it to tracefile if necessary. | |
600 | */ | |
601 | static void *thread_poll_fds(void *data) | |
602 | { | |
603 | int num_rdy, num_hup, high_prio, ret, i; | |
604 | struct pollfd *pollfd = NULL; | |
605 | /* local view of the fds */ | |
6aea26bc | 606 | struct ltt_kconsumerd_fd **local_kconsumerd_fd = NULL; |
d4a1283e JD |
607 | /* local view of fds_count */ |
608 | int nb_fd = 0; | |
252fd492 JD |
609 | char tmp; |
610 | int tmp2; | |
d4a1283e JD |
611 | |
612 | ret = pipe(thread_pipe); | |
613 | if (ret < 0) { | |
614 | perror("Error creating pipe"); | |
615 | goto end; | |
616 | } | |
617 | ||
6aea26bc JD |
618 | local_kconsumerd_fd = malloc(sizeof(struct ltt_kconsumerd_fd)); |
619 | ||
d4a1283e JD |
620 | while (1) { |
621 | high_prio = 0; | |
622 | num_hup = 0; | |
623 | ||
624 | /* | |
625 | * the ltt_fd_list has been updated, we need to update our | |
626 | * local array as well | |
627 | */ | |
914a571b | 628 | if (update_fd_array == 1) { |
4abc0780 JD |
629 | if (pollfd != NULL) { |
630 | free(pollfd); | |
631 | pollfd = NULL; | |
632 | } | |
633 | if (local_kconsumerd_fd != NULL) { | |
634 | free(local_kconsumerd_fd); | |
635 | local_kconsumerd_fd = NULL; | |
636 | } | |
637 | /* allocate for all fds + 1 for the poll_pipe */ | |
638 | pollfd = malloc((fds_count + 1) * sizeof(struct pollfd)); | |
639 | if (pollfd == NULL) { | |
640 | perror("pollfd malloc"); | |
641 | goto end; | |
642 | } | |
643 | /* allocate for all fds + 1 for the poll_pipe */ | |
644 | local_kconsumerd_fd = malloc((fds_count + 1) * sizeof(struct ltt_kconsumerd_fd)); | |
645 | if (local_kconsumerd_fd == NULL) { | |
646 | perror("local_kconsumerd_fd malloc"); | |
647 | goto end; | |
648 | } | |
649 | ||
6aea26bc | 650 | ret = update_poll_array(&pollfd, local_kconsumerd_fd); |
d4a1283e JD |
651 | if (ret < 0) { |
652 | ERR("Error in allocating pollfd or local_outfds"); | |
653 | send_error(KCONSUMERD_POLL_ERROR); | |
654 | goto end; | |
655 | } | |
656 | nb_fd = ret; | |
657 | } | |
658 | ||
659 | /* poll on the array of fds */ | |
252fd492 JD |
660 | DBG("polling on %d fd", nb_fd + 1); |
661 | num_rdy = poll(pollfd, nb_fd + 1, -1); | |
d4a1283e JD |
662 | DBG("poll num_rdy : %d", num_rdy); |
663 | if (num_rdy == -1) { | |
664 | perror("Poll error"); | |
665 | send_error(KCONSUMERD_POLL_ERROR); | |
666 | goto end; | |
667 | } | |
668 | ||
252fd492 JD |
669 | /* |
670 | * if only the poll_pipe triggered poll to return just return to the | |
671 | * beginning of the loop to update the array | |
672 | */ | |
673 | if (num_rdy == 1 && pollfd[nb_fd].revents == POLLIN) { | |
674 | DBG("poll_pipe wake up"); | |
675 | tmp2 = read(poll_pipe[0], &tmp, 1); | |
676 | continue; | |
677 | } | |
678 | ||
d4a1283e JD |
679 | /* Take care of high priority channels first. */ |
680 | for (i = 0; i < nb_fd; i++) { | |
681 | switch(pollfd[i].revents) { | |
914a571b JD |
682 | case POLLERR: |
683 | ERR("Error returned in polling fd %d.", pollfd[i].fd); | |
684 | num_hup++; | |
685 | send_error(KCONSUMERD_POLL_ERROR); | |
686 | break; | |
687 | case POLLHUP: | |
688 | ERR("Polling fd %d tells it has hung up.", pollfd[i].fd); | |
689 | num_hup++; | |
690 | break; | |
691 | case POLLNVAL: | |
692 | ERR("Polling fd %d tells fd is not open.", pollfd[i].fd); | |
693 | send_error(KCONSUMERD_POLL_NVAL); | |
694 | num_hup++; | |
695 | break; | |
696 | case POLLPRI: | |
697 | DBG("Urgent read on fd %d", pollfd[i].fd); | |
698 | high_prio = 1; | |
699 | ret = read_subbuffer(local_kconsumerd_fd[i]); | |
700 | /* it's ok to have an unavailable sub-buffer (FIXME : is it ?) */ | |
701 | if (ret == EAGAIN) { | |
702 | ret = 0; | |
703 | } | |
704 | break; | |
d4a1283e JD |
705 | } |
706 | } | |
707 | ||
708 | /* If every buffer FD has hung up, we end the read loop here */ | |
709 | if (nb_fd > 0 && num_hup == nb_fd) { | |
710 | DBG("every buffer FD has hung up\n"); | |
711 | send_error(KCONSUMERD_POLL_HUP); | |
6aea26bc | 712 | goto end; |
d4a1283e JD |
713 | } |
714 | ||
715 | /* Take care of low priority channels. */ | |
914a571b | 716 | if (high_prio == 0) { |
d4a1283e | 717 | for (i = 0; i < nb_fd; i++) { |
914a571b JD |
718 | if (pollfd[i].revents == POLLIN) { |
719 | DBG("Normal read on fd %d", pollfd[i].fd); | |
720 | ret = read_subbuffer(local_kconsumerd_fd[i]); | |
721 | /* it's ok to have an unavailable subbuffer (FIXME : is it ?) */ | |
722 | if (ret == EAGAIN) { | |
723 | ret = 0; | |
724 | } | |
d4a1283e JD |
725 | } |
726 | } | |
727 | } | |
728 | } | |
729 | end: | |
730 | if (pollfd != NULL) { | |
731 | free(pollfd); | |
732 | pollfd = NULL; | |
733 | } | |
734 | if (local_kconsumerd_fd != NULL) { | |
735 | free(local_kconsumerd_fd); | |
736 | local_kconsumerd_fd = NULL; | |
737 | } | |
bcd8d9db | 738 | cleanup(); |
d4a1283e JD |
739 | return NULL; |
740 | } | |
741 | ||
742 | /* | |
743 | * usage function on stderr | |
744 | */ | |
745 | static void usage(void) | |
746 | { | |
747 | fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname); | |
748 | fprintf(stderr, " -h, --help " | |
749 | "Display this usage.\n"); | |
750 | fprintf(stderr, " -c, --kconsumerd-cmd-sock PATH " | |
751 | "Specify path for the command socket\n"); | |
752 | fprintf(stderr, " -e, --kconsumerd-err-sock PATH " | |
753 | "Specify path for the error socket\n"); | |
754 | fprintf(stderr, " -d, --daemonize " | |
755 | "Start as a daemon.\n"); | |
756 | fprintf(stderr, " -q, --quiet " | |
757 | "No output at all.\n"); | |
758 | fprintf(stderr, " -v, --verbose " | |
759 | "Verbose mode. Activate DBG() macro.\n"); | |
760 | fprintf(stderr, " -V, --version " | |
761 | "Show version number.\n"); | |
762 | } | |
763 | ||
764 | /* | |
765 | * daemon argument parsing | |
766 | */ | |
767 | static void parse_args(int argc, char **argv) | |
768 | { | |
769 | int c; | |
770 | ||
771 | static struct option long_options[] = { | |
772 | { "kconsumerd-cmd-sock", 1, 0, 'c' }, | |
773 | { "kconsumerd-err-sock", 1, 0, 'e' }, | |
774 | { "daemonize", 0, 0, 'd' }, | |
775 | { "help", 0, 0, 'h' }, | |
776 | { "quiet", 0, 0, 'q' }, | |
777 | { "verbose", 0, 0, 'v' }, | |
778 | { "version", 0, 0, 'V' }, | |
779 | { NULL, 0, 0, 0 } | |
780 | }; | |
781 | ||
782 | while (1) { | |
783 | int option_index = 0; | |
784 | c = getopt_long(argc, argv, "dhqvV" "c:e:", long_options, &option_index); | |
785 | if (c == -1) { | |
786 | break; | |
787 | } | |
788 | ||
789 | switch (c) { | |
914a571b JD |
790 | case 0: |
791 | fprintf(stderr, "option %s", long_options[option_index].name); | |
792 | if (optarg) { | |
793 | fprintf(stderr, " with arg %s\n", optarg); | |
794 | } | |
795 | break; | |
796 | case 'c': | |
797 | snprintf(command_sock_path, PATH_MAX, "%s", optarg); | |
798 | break; | |
799 | case 'e': | |
800 | snprintf(error_sock_path, PATH_MAX, "%s", optarg); | |
801 | break; | |
802 | case 'd': | |
803 | opt_daemon = 1; | |
804 | break; | |
805 | case 'h': | |
806 | usage(); | |
807 | exit(EXIT_FAILURE); | |
808 | case 'q': | |
809 | opt_quiet = 1; | |
810 | break; | |
811 | case 'v': | |
812 | opt_verbose = 1; | |
813 | break; | |
814 | case 'V': | |
815 | fprintf(stdout, "%s\n", VERSION); | |
816 | exit(EXIT_SUCCESS); | |
817 | default: | |
818 | usage(); | |
819 | exit(EXIT_FAILURE); | |
d4a1283e JD |
820 | } |
821 | } | |
822 | } | |
823 | ||
824 | ||
825 | /* | |
826 | * main | |
827 | */ | |
828 | int main(int argc, char **argv) | |
829 | { | |
830 | int i; | |
831 | int ret = 0; | |
832 | void *status; | |
833 | ||
834 | /* Parse arguments */ | |
835 | progname = argv[0]; | |
836 | parse_args(argc, argv); | |
837 | ||
838 | /* Daemonize */ | |
839 | if (opt_daemon) { | |
840 | ret = daemon(0, 0); | |
841 | if (ret < 0) { | |
842 | perror("daemon"); | |
843 | goto error; | |
844 | } | |
845 | } | |
846 | ||
847 | if (strlen(command_sock_path) == 0) { | |
848 | snprintf(command_sock_path, PATH_MAX, | |
849 | KCONSUMERD_CMD_SOCK_PATH); | |
850 | } | |
851 | if (strlen(error_sock_path) == 0) { | |
852 | snprintf(error_sock_path, PATH_MAX, | |
853 | KCONSUMERD_ERR_SOCK_PATH); | |
854 | } | |
855 | ||
856 | if (set_signal_handler() < 0) { | |
857 | goto error; | |
858 | } | |
859 | ||
252fd492 JD |
860 | /* create the pipe to wake to polling thread when needed */ |
861 | ret = pipe(poll_pipe); | |
862 | if (ret < 0) { | |
863 | perror("Error creating poll pipe"); | |
864 | goto end; | |
865 | } | |
866 | ||
d4a1283e JD |
867 | /* Connect to the socket created by ltt-sessiond to report errors */ |
868 | DBG("Connecting to error socket %s", error_sock_path); | |
869 | error_socket = lttcomm_connect_unix_sock(error_sock_path); | |
870 | /* not a fatal error, but all communication with ltt-sessiond will fail */ | |
871 | if (error_socket < 0) { | |
872 | WARN("Cannot connect to error socket, is ltt-sessiond started ?"); | |
873 | } | |
874 | ||
875 | /* Create the thread to manage the receive of fd */ | |
876 | ret = pthread_create(&threads[0], NULL, thread_receive_fds, (void *) NULL); | |
877 | if (ret != 0) { | |
878 | perror("pthread_create"); | |
879 | goto error; | |
880 | } | |
881 | ||
882 | /* Create thread to manage the polling/writing of traces */ | |
883 | ret = pthread_create(&threads[1], NULL, thread_poll_fds, (void *) NULL); | |
884 | if (ret != 0) { | |
885 | perror("pthread_create"); | |
886 | goto error; | |
887 | } | |
888 | ||
889 | for (i = 0; i < 2; i++) { | |
890 | ret = pthread_join(threads[i], &status); | |
891 | if (ret != 0) { | |
892 | perror("pthread_join"); | |
893 | goto error; | |
894 | } | |
895 | } | |
896 | ret = EXIT_SUCCESS; | |
897 | send_error(KCONSUMERD_EXIT_SUCCESS); | |
898 | goto end; | |
899 | ||
900 | error: | |
901 | ret = EXIT_FAILURE; | |
902 | send_error(KCONSUMERD_EXIT_FAILURE); | |
903 | ||
904 | end: | |
905 | cleanup(); | |
906 | ||
907 | return ret; | |
908 | } |