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b0a99af4 MD |
1 | /* |
2 | * ust-basic-tracing.c - Basic single-session, single-channel, single-process UST tracing | |
3 | * | |
4 | * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the Free | |
9 | * Software Foundation; only version 2 of the License. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along with | |
17 | * this program; if not, write to the Free Software Foundation, Inc., 59 Temple | |
18 | * Place - Suite 330, Boston, MA 02111-1307, USA. | |
19 | */ | |
20 | ||
21 | #define _LARGEFILE64_SOURCE | |
22 | #include <errno.h> | |
23 | #include <stdio.h> | |
24 | #include <stdlib.h> | |
25 | #include <string.h> | |
26 | #include <signal.h> | |
27 | #include <unistd.h> | |
28 | #include <sys/wait.h> | |
29 | #include <sys/types.h> | |
30 | #include <sys/stat.h> | |
31 | #include <fcntl.h> | |
32 | #include <sys/mman.h> | |
33 | #include <limits.h> | |
34 | #include <urcu/futex.h> | |
35 | #include <urcu/uatomic.h> | |
36 | #include <assert.h> | |
37 | #include <sys/socket.h> | |
38 | ||
39 | #include "lttng-ust-comm.h" | |
40 | #include "../../libringbuffer/backend.h" | |
41 | #include "../../libringbuffer/frontend.h" | |
42 | ||
43 | #define MAX_NR_STREAMS 64 | |
44 | #define MAX_NR_EVENTS 128 | |
45 | ||
46 | struct object_data { | |
47 | int handle; | |
48 | int shm_fd; | |
49 | int wait_fd; | |
50 | uint64_t memory_map_size; | |
51 | }; | |
52 | ||
53 | static int session_handle; | |
54 | static struct object_data metadata_stream_data; | |
55 | static struct object_data metadata_data; | |
56 | static struct object_data channel_data; | |
57 | static struct object_data stream_data[MAX_NR_STREAMS]; | |
58 | static int event_handle[MAX_NR_EVENTS]; | |
8de38cf7 | 59 | static int context_handle; |
b0a99af4 MD |
60 | |
61 | static int apps_socket = -1; | |
62 | static char apps_sock_path[PATH_MAX]; | |
63 | static char local_apps_wait_shm_path[PATH_MAX]; | |
64 | ||
65 | static volatile int quit_program; | |
66 | ||
67 | static void handle_signals(int signo) | |
68 | { | |
69 | quit_program = 1; | |
70 | } | |
71 | ||
b0a99af4 MD |
72 | static |
73 | int open_streams(int sock, int channel_handle, struct object_data *stream_datas, | |
74 | int nr_check) | |
75 | { | |
76 | int ret, k = 0; | |
77 | ||
78 | for (;;) { | |
57773204 MD |
79 | struct ustcomm_ust_msg lum; |
80 | struct ustcomm_ust_reply lur; | |
b0a99af4 MD |
81 | |
82 | memset(&lum, 0, sizeof(lum)); | |
83 | lum.handle = channel_handle; | |
84 | lum.cmd = LTTNG_UST_STREAM; | |
57773204 | 85 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
86 | if (!ret) { |
87 | assert(k < nr_check); | |
88 | stream_datas[k].handle = lur.ret_val; | |
89 | printf("received stream handle %u\n", | |
90 | stream_datas[k].handle); | |
57773204 | 91 | if (lur.ret_code == USTCOMM_OK) { |
b0a99af4 MD |
92 | ssize_t len; |
93 | ||
94 | stream_datas[k].memory_map_size = lur.u.stream.memory_map_size; | |
95 | /* get shm fd */ | |
57773204 | 96 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
97 | if (len < 0) |
98 | return -EINVAL; | |
99 | stream_datas[k].shm_fd = len; | |
100 | /* get wait fd */ | |
57773204 | 101 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
102 | if (len < 0) |
103 | return -EINVAL; | |
104 | stream_datas[k].wait_fd = len; | |
105 | } | |
106 | k++; | |
107 | } | |
108 | if (ret == -ENOENT) | |
109 | break; | |
110 | if (ret) | |
111 | return ret; | |
112 | } | |
113 | return 0; | |
114 | } | |
115 | ||
116 | static | |
117 | int close_streams(int sock, struct object_data *stream_datas, int nr_check) | |
118 | { | |
119 | int ret, k; | |
120 | ||
121 | for (k = 0; k < nr_check; k++) { | |
57773204 MD |
122 | struct ustcomm_ust_msg lum; |
123 | struct ustcomm_ust_reply lur; | |
b0a99af4 MD |
124 | |
125 | if (!stream_datas[k].handle) | |
126 | continue; | |
127 | memset(&lum, 0, sizeof(lum)); | |
128 | lum.handle = stream_datas[k].handle; | |
129 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 130 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
131 | if (ret) { |
132 | printf("Error closing stream\n"); | |
133 | return ret; | |
134 | } | |
135 | if (stream_datas[k].shm_fd >= 0) { | |
136 | ret = close(stream_datas[k].shm_fd); | |
137 | if (ret) { | |
138 | printf("Error closing stream shm_fd\n"); | |
139 | return ret; | |
140 | } | |
141 | } | |
142 | if (stream_datas[k].wait_fd >= 0) { | |
143 | ret = close(stream_datas[k].wait_fd); | |
144 | if (ret) { | |
145 | printf("Error closing stream wait_fd\n"); | |
146 | return ret; | |
147 | } | |
148 | } | |
149 | } | |
150 | return 0; | |
151 | } | |
152 | ||
153 | static | |
154 | struct shm_handle *map_channel(struct object_data *chan_data, | |
155 | struct object_data *stream_datas, int nr_check) | |
156 | { | |
157 | struct shm_handle *handle; | |
158 | struct channel *chan; | |
159 | int k, ret; | |
160 | ||
161 | /* map metadata channel */ | |
162 | handle = channel_handle_create(chan_data->shm_fd, | |
163 | chan_data->wait_fd, | |
164 | chan_data->memory_map_size); | |
165 | if (!handle) { | |
166 | printf("create handle error\n"); | |
167 | return NULL; | |
168 | } | |
169 | chan_data->shm_fd = -1; | |
170 | chan_data->wait_fd = -1; | |
171 | chan = shmp(handle, handle->chan); | |
172 | ||
173 | for (k = 0; k < nr_check; k++) { | |
174 | struct object_data *stream_data = &stream_datas[k]; | |
175 | ||
176 | if (!stream_data->handle) | |
177 | break; | |
178 | /* map stream */ | |
179 | ret = channel_handle_add_stream(handle, | |
180 | stream_data->shm_fd, | |
181 | stream_data->wait_fd, | |
182 | stream_data->memory_map_size); | |
183 | if (ret) { | |
184 | printf("add stream error\n"); | |
185 | goto error_destroy; | |
186 | } | |
187 | stream_data->shm_fd = -1; | |
188 | stream_data->wait_fd = -1; | |
189 | } | |
190 | return handle; | |
191 | ||
192 | error_destroy: | |
193 | channel_destroy(chan, handle, 1); | |
194 | return NULL; | |
195 | } | |
196 | ||
197 | static | |
198 | void unmap_channel(struct shm_handle *handle) | |
199 | { | |
200 | struct channel *chan; | |
201 | ||
202 | chan = shmp(handle, handle->chan); | |
203 | /* unmap channel */ | |
204 | channel_destroy(chan, handle, 1); | |
205 | } | |
206 | ||
207 | static | |
208 | int consume_stream(struct shm_handle *handle, int cpu, char *outfile) | |
209 | { | |
210 | struct channel *chan; | |
211 | struct lib_ring_buffer *buf; | |
212 | int outfd, ret; | |
213 | int shm_fd, wait_fd; | |
214 | uint64_t memory_map_size; | |
215 | ||
216 | chan = shmp(handle, handle->chan); | |
217 | ||
218 | /* open stream */ | |
219 | buf = channel_get_ring_buffer(&chan->backend.config, | |
220 | chan, cpu, handle, &shm_fd, &wait_fd, &memory_map_size); | |
221 | if (!buf) | |
222 | return -ENOENT; | |
223 | ret = lib_ring_buffer_open_read(buf, handle, 1); | |
224 | if (ret) { | |
225 | return -1; | |
226 | } | |
227 | ||
228 | /* copy */ | |
229 | outfd = open(outfile, O_WRONLY | O_CREAT | O_LARGEFILE | O_TRUNC, | |
230 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); | |
231 | if (outfd < 0) { | |
232 | perror("open output"); | |
233 | return -1; | |
234 | } | |
235 | ||
236 | printf("Waiting for buffer data for %s\n", outfile); | |
237 | for (;;) { | |
238 | unsigned long read_size; | |
239 | unsigned long copy_size; | |
240 | char *ptr; | |
241 | ||
242 | ret = lib_ring_buffer_get_next_subbuf(buf, handle); | |
243 | printf("get next ret %d\n", ret); | |
244 | if (ret == -ENODATA) | |
245 | break; | |
246 | if (ret == -EAGAIN) { | |
247 | sleep(1); | |
248 | continue; | |
249 | } | |
250 | if (ret) { | |
251 | printf("Error %d in lib_ring_buffer_get_next_subbuf\n", ret); | |
252 | return -1; | |
253 | } | |
254 | read_size = lib_ring_buffer_get_read_data_size( | |
255 | &chan->backend.config, buf, handle); | |
256 | read_size = PAGE_ALIGN(read_size); | |
257 | ptr = lib_ring_buffer_read_offset_address( | |
258 | &buf->backend, 0, handle); | |
259 | printf("WRITE: copy %lu bytes\n", read_size); | |
260 | copy_size = write(outfd, ptr, read_size); | |
261 | if (copy_size < read_size) { | |
262 | printf("write issue: copied %zd, expected %lu\n", copy_size, read_size); | |
263 | } | |
264 | lib_ring_buffer_put_next_subbuf(buf, handle); | |
265 | } | |
266 | ||
267 | ret = close(outfd); | |
268 | if (ret) { | |
269 | perror("close"); | |
270 | return -1; | |
271 | } | |
272 | ||
273 | /* close stream */ | |
274 | lib_ring_buffer_release_read(buf, handle, 1); | |
275 | return 0; | |
276 | } | |
277 | ||
278 | static | |
279 | int consume_buffers(const char *outputpath) | |
280 | { | |
281 | int k, ret; | |
282 | mode_t old_umask; | |
283 | char pathname[PATH_MAX]; | |
284 | struct shm_handle *handle; | |
285 | ||
286 | snprintf(pathname, PATH_MAX - 1, "%s", outputpath); | |
287 | old_umask = umask(0); | |
288 | ret = mkdir(pathname, S_IRWXU | S_IRWXG); | |
289 | if (ret && errno != EEXIST) { | |
290 | perror("mkdir"); | |
291 | umask(old_umask); | |
292 | return -1; | |
293 | } | |
294 | umask(old_umask); | |
295 | ||
296 | /* copy metadata */ | |
297 | handle = map_channel(&metadata_data, | |
298 | &metadata_stream_data, 1); | |
299 | if (!handle) | |
300 | return -1; | |
301 | snprintf(pathname, PATH_MAX - 1, | |
302 | "%s/metadata", outputpath); | |
303 | ret = consume_stream(handle, -1, pathname); | |
304 | if (ret && ret != -ENOENT) { | |
305 | printf("Error in consume_stream\n"); | |
306 | return ret; | |
307 | } | |
308 | unmap_channel(handle); | |
309 | ||
310 | /* copy binary data */ | |
311 | handle = map_channel(&channel_data, | |
312 | stream_data, MAX_NR_STREAMS); | |
313 | if (!handle) | |
314 | return -1; | |
315 | for (k = 0; k < MAX_NR_STREAMS; k++) { | |
316 | snprintf(pathname, PATH_MAX - 1, | |
317 | "%s/data_%u", outputpath, k); | |
318 | ret = consume_stream(handle, k, pathname); | |
319 | if (ret && ret != -ENOENT) { | |
320 | printf("Error in consume_stream\n"); | |
321 | return ret; | |
322 | } | |
323 | } | |
324 | unmap_channel(handle); | |
325 | ||
326 | return 0; | |
327 | } | |
328 | ||
57773204 | 329 | static |
b0a99af4 MD |
330 | int send_app_msgs(int sock, const char *outputpath, |
331 | unsigned int nr_events, const char **event_names) | |
332 | { | |
57773204 MD |
333 | struct ustcomm_ust_msg lum; |
334 | struct ustcomm_ust_reply lur; | |
b0a99af4 MD |
335 | int ret, k; |
336 | ||
337 | /* Create session */ | |
338 | memset(&lum, 0, sizeof(lum)); | |
339 | lum.handle = LTTNG_UST_ROOT_HANDLE; | |
340 | lum.cmd = LTTNG_UST_SESSION; | |
57773204 | 341 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
342 | if (ret) |
343 | return ret; | |
344 | session_handle = lur.ret_val; | |
345 | printf("received session handle %u\n", session_handle); | |
346 | ||
347 | /* Create metadata channel */ | |
348 | memset(&lum, 0, sizeof(lum)); | |
349 | lum.handle = session_handle; | |
350 | lum.cmd = LTTNG_UST_METADATA; | |
351 | lum.u.channel.overwrite = 0; | |
352 | lum.u.channel.subbuf_size = 32768; | |
353 | lum.u.channel.num_subbuf = 4; | |
354 | lum.u.channel.switch_timer_interval = 0; | |
355 | lum.u.channel.read_timer_interval = 0; | |
356 | lum.u.channel.output = LTTNG_UST_MMAP; | |
57773204 | 357 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
358 | if (ret) |
359 | return ret; | |
360 | metadata_data.handle = lur.ret_val; | |
361 | printf("received metadata handle %u\n", metadata_data.handle); | |
57773204 | 362 | if (lur.ret_code == USTCOMM_OK) { |
b0a99af4 MD |
363 | ssize_t len; |
364 | ||
365 | metadata_data.memory_map_size = lur.u.channel.memory_map_size; | |
366 | /* get shm fd */ | |
57773204 | 367 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
368 | if (len < 0) |
369 | return -EINVAL; | |
370 | metadata_data.shm_fd = len; | |
371 | /* get wait fd */ | |
57773204 | 372 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
373 | if (len < 0) |
374 | return -EINVAL; | |
375 | metadata_data.wait_fd = len; | |
376 | } | |
377 | ||
378 | ret = open_streams(sock, metadata_data.handle, | |
379 | &metadata_stream_data, 1); | |
380 | if (ret) { | |
381 | printf("Error in open_streams\n"); | |
382 | return ret; | |
383 | } | |
384 | ||
385 | /* Create data channel */ | |
386 | memset(&lum, 0, sizeof(lum)); | |
387 | lum.handle = session_handle; | |
388 | lum.cmd = LTTNG_UST_CHANNEL; | |
389 | //lum.u.channel.overwrite = 0; | |
390 | lum.u.channel.overwrite = 1; | |
391 | lum.u.channel.subbuf_size = 32768; | |
392 | lum.u.channel.num_subbuf = 8; | |
393 | //lum.u.channel.num_subbuf = 4; | |
394 | //lum.u.channel.num_subbuf = 2; | |
395 | lum.u.channel.switch_timer_interval = 0; | |
396 | lum.u.channel.read_timer_interval = 0; | |
397 | lum.u.channel.output = LTTNG_UST_MMAP; | |
57773204 | 398 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
399 | if (ret) |
400 | return ret; | |
401 | channel_data.handle = lur.ret_val; | |
402 | printf("received channel handle %u\n", channel_data.handle); | |
57773204 | 403 | if (lur.ret_code == USTCOMM_OK) { |
b0a99af4 MD |
404 | ssize_t len; |
405 | ||
406 | channel_data.memory_map_size = lur.u.channel.memory_map_size; | |
407 | /* get shm fd */ | |
57773204 | 408 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
409 | if (len < 0) |
410 | return -EINVAL; | |
411 | channel_data.shm_fd = len; | |
412 | /* get wait fd */ | |
57773204 | 413 | len = ustcomm_recv_fd(sock); |
b0a99af4 MD |
414 | if (len < 0) |
415 | return -EINVAL; | |
416 | channel_data.wait_fd = len; | |
417 | } | |
418 | ||
419 | /* Create events */ | |
420 | for (k = 0; k < nr_events; k++) { | |
421 | memset(&lum, 0, sizeof(lum)); | |
422 | lum.handle = channel_data.handle; | |
423 | lum.cmd = LTTNG_UST_EVENT; | |
424 | strncpy(lum.u.event.name, event_names[k], | |
425 | LTTNG_UST_SYM_NAME_LEN); | |
426 | lum.u.event.instrumentation = LTTNG_UST_TRACEPOINT; | |
57773204 | 427 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
428 | if (ret) |
429 | return ret; | |
430 | event_handle[k] = lur.ret_val; | |
431 | printf("received event handle %u\n", event_handle[k]); | |
432 | } | |
433 | ||
3b402b40 | 434 | /* Attach vtid context */ |
8de38cf7 MD |
435 | memset(&lum, 0, sizeof(lum)); |
436 | lum.handle = channel_data.handle; | |
437 | lum.cmd = LTTNG_UST_CONTEXT; | |
3b402b40 MD |
438 | lum.u.context.ctx = LTTNG_UST_CONTEXT_VTID; |
439 | //lum.u.context.ctx = LTTNG_UST_CONTEXT_PTHREAD_ID; | |
4847e9bb MD |
440 | //lum.u.context.ctx = LTTNG_UST_CONTEXT_VPID; |
441 | //lum.u.context.ctx = LTTNG_UST_CONTEXT_PROCNAME; | |
57773204 | 442 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
8de38cf7 MD |
443 | if (ret) |
444 | return ret; | |
445 | context_handle = lur.ret_val; | |
446 | printf("received context handle %u\n", context_handle); | |
447 | ||
b0a99af4 MD |
448 | /* Get references to channel streams */ |
449 | ret = open_streams(sock, channel_data.handle, | |
450 | stream_data, MAX_NR_STREAMS); | |
451 | if (ret) { | |
452 | printf("Error in open_streams\n"); | |
453 | return ret; | |
454 | } | |
455 | ||
456 | memset(&lum, 0, sizeof(lum)); | |
457 | lum.handle = session_handle; | |
458 | lum.cmd = LTTNG_UST_SESSION_START; | |
57773204 | 459 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
460 | if (ret) |
461 | return ret; | |
462 | printf("Session handle %u started.\n", session_handle); | |
463 | ||
464 | /* Tell application registration is done */ | |
465 | memset(&lum, 0, sizeof(lum)); | |
466 | lum.handle = LTTNG_UST_ROOT_HANDLE; | |
467 | lum.cmd = LTTNG_UST_REGISTER_DONE; | |
57773204 | 468 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
469 | if (ret) |
470 | return ret; | |
471 | printf("Registration done acknowledged.\n"); | |
472 | ||
473 | sleep(4); | |
474 | ||
475 | ret = consume_buffers(outputpath); | |
476 | if (ret) { | |
477 | printf("Error in consume_buffers\n"); | |
478 | return ret; | |
479 | } | |
480 | ||
481 | /* Release data channel */ | |
482 | /* Release streams */ | |
483 | ret = close_streams(sock, stream_data, | |
484 | MAX_NR_STREAMS); | |
485 | if (ret) | |
486 | return ret; | |
487 | ||
8de38cf7 MD |
488 | /* Release context */ |
489 | memset(&lum, 0, sizeof(lum)); | |
490 | lum.handle = context_handle; | |
491 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 492 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
8de38cf7 MD |
493 | if (ret) |
494 | return ret; | |
495 | ||
b0a99af4 MD |
496 | /* Release events */ |
497 | for (k = 0; k < nr_events; k++) { | |
498 | memset(&lum, 0, sizeof(lum)); | |
499 | lum.handle = event_handle[k]; | |
500 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 501 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
502 | if (ret) |
503 | return ret; | |
504 | } | |
505 | memset(&lum, 0, sizeof(lum)); | |
506 | lum.handle = channel_data.handle; | |
507 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 508 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
509 | if (ret) |
510 | return ret; | |
511 | if (channel_data.shm_fd >= 0) { | |
512 | ret = close(channel_data.shm_fd); | |
513 | if (ret) | |
514 | return ret; | |
515 | } | |
516 | if (channel_data.wait_fd >= 0) { | |
517 | ret = close(channel_data.wait_fd); | |
518 | if (ret) | |
519 | return ret; | |
520 | } | |
521 | ||
522 | /* Release metadata channel */ | |
523 | ret = close_streams(sock, &metadata_stream_data, 1); | |
524 | if (ret) | |
525 | return ret; | |
526 | ||
527 | memset(&lum, 0, sizeof(lum)); | |
528 | lum.handle = metadata_data.handle; | |
529 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 530 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
531 | if (ret) |
532 | return ret; | |
533 | if (metadata_data.shm_fd >= 0) { | |
534 | ret = close(metadata_data.shm_fd); | |
535 | if (ret) | |
536 | return ret; | |
537 | } | |
538 | if (metadata_data.wait_fd >= 0) { | |
539 | ret = close(metadata_data.wait_fd); | |
540 | if (ret) | |
541 | return ret; | |
542 | } | |
543 | ||
544 | /* Release session */ | |
545 | memset(&lum, 0, sizeof(lum)); | |
546 | lum.handle = session_handle; | |
547 | lum.cmd = LTTNG_UST_RELEASE; | |
57773204 | 548 | ret = ustcomm_send_app_cmd(sock, &lum, &lur); |
b0a99af4 MD |
549 | if (ret) |
550 | return ret; | |
551 | ||
552 | return 0; | |
553 | } | |
554 | ||
555 | /* | |
556 | * Using fork to set umask in the child process (not multi-thread safe). We | |
557 | * deal with the shm_open vs ftruncate race (happening when the sessiond owns | |
558 | * the shm and does not let everybody modify it, to ensure safety against | |
559 | * shm_unlink) by simply letting the mmap fail and retrying after a few | |
560 | * seconds. For global shm, everybody has rw access to it until the sessiond | |
561 | * starts. | |
562 | */ | |
563 | static int get_wait_shm(char *shm_path, size_t mmap_size, int global) | |
564 | { | |
565 | int wait_shm_fd, ret; | |
566 | mode_t mode; | |
567 | ||
568 | /* Default permissions */ | |
569 | mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP; | |
570 | ||
571 | /* Change owner of the shm path */ | |
572 | if (global) { | |
573 | ret = chown(shm_path, 0, 0); | |
574 | if (ret < 0) { | |
575 | if (errno != ENOENT) { | |
576 | perror("chown wait shm"); | |
577 | goto error; | |
578 | } | |
579 | } | |
580 | ||
581 | /* | |
582 | * If global session daemon, any application can register so the shm | |
583 | * needs to be set in read-only mode for others. | |
584 | */ | |
585 | mode |= S_IROTH; | |
586 | } else { | |
587 | ret = chown(shm_path, getuid(), getgid()); | |
588 | if (ret < 0) { | |
589 | if (errno != ENOENT) { | |
590 | perror("chown wait shm"); | |
591 | goto error; | |
592 | } | |
593 | } | |
594 | } | |
595 | ||
596 | /* | |
597 | * Set permissions to the shm even if we did not create the shm. | |
598 | */ | |
599 | ret = chmod(shm_path, mode); | |
600 | if (ret < 0) { | |
601 | if (errno != ENOENT) { | |
602 | perror("chmod wait shm"); | |
603 | goto error; | |
604 | } | |
605 | } | |
606 | ||
607 | /* | |
608 | * We're alone in a child process, so we can modify the process-wide | |
609 | * umask. | |
610 | */ | |
611 | umask(~mode); | |
612 | ||
613 | /* | |
614 | * Try creating shm (or get rw access). We don't do an exclusive open, | |
615 | * because we allow other processes to create+ftruncate it concurrently. | |
616 | */ | |
617 | wait_shm_fd = shm_open(shm_path, O_RDWR | O_CREAT, mode); | |
618 | if (wait_shm_fd < 0) { | |
619 | perror("shm_open wait shm"); | |
620 | goto error; | |
621 | } | |
622 | ||
623 | ret = ftruncate(wait_shm_fd, mmap_size); | |
624 | if (ret < 0) { | |
625 | perror("ftruncate wait shm"); | |
626 | exit(EXIT_FAILURE); | |
627 | } | |
628 | ||
629 | ret = fchmod(wait_shm_fd, mode); | |
630 | if (ret < 0) { | |
631 | perror("fchmod"); | |
632 | exit(EXIT_FAILURE); | |
633 | } | |
634 | ||
635 | printf("Got the wait shm fd %d\n", wait_shm_fd); | |
636 | ||
637 | return wait_shm_fd; | |
638 | ||
639 | error: | |
640 | printf("Failing to get the wait shm fd\n"); | |
641 | ||
642 | return -1; | |
643 | } | |
644 | ||
645 | int update_futex(int fd, int active) | |
646 | { | |
647 | size_t mmap_size = sysconf(_SC_PAGE_SIZE); | |
648 | char *wait_shm_mmap; | |
649 | int ret; | |
650 | ||
651 | wait_shm_mmap = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, | |
652 | MAP_SHARED, fd, 0); | |
653 | if (wait_shm_mmap == MAP_FAILED) { | |
654 | perror("mmap"); | |
655 | goto error; | |
656 | } | |
657 | ||
658 | if (active) { | |
659 | uatomic_set((int32_t *) wait_shm_mmap, 1); | |
660 | futex_async((int32_t *) wait_shm_mmap, FUTEX_WAKE, | |
661 | INT_MAX, NULL, NULL, 0); | |
662 | } else { | |
663 | uatomic_set((int32_t *) wait_shm_mmap, 0); | |
664 | } | |
665 | ret = munmap(wait_shm_mmap, mmap_size); | |
666 | if (ret) { | |
667 | perror("Error unmapping wait shm"); | |
668 | goto error; | |
669 | } | |
670 | return 0; | |
671 | error: | |
672 | return -1; | |
673 | } | |
674 | ||
675 | /* | |
676 | * Set open files limit to unlimited. This daemon can open a large number of | |
677 | * file descriptors in order to consumer multiple kernel traces. | |
678 | */ | |
679 | static void set_ulimit(void) | |
680 | { | |
681 | int ret; | |
682 | struct rlimit lim; | |
683 | ||
684 | /* | |
685 | * If not root, we cannot increase our max open files. But our | |
686 | * scope is then limited to processes from a single user. | |
687 | */ | |
688 | if (getuid() != 0) | |
689 | return; | |
690 | /* The kernel does not allowed an infinite limit for open files */ | |
691 | lim.rlim_cur = 65535; | |
692 | lim.rlim_max = 65535; | |
693 | ||
694 | ret = setrlimit(RLIMIT_NOFILE, &lim); | |
695 | if (ret < 0) { | |
696 | perror("failed to set open files limit"); | |
697 | } | |
698 | } | |
699 | ||
700 | /* | |
701 | * Usage: | |
702 | * ./ust-basic-tracing outputpath event_name1 event_name2 .... | |
703 | */ | |
704 | int main(int argc, const char **argv) | |
705 | { | |
706 | const char *home_dir; | |
707 | int ret, wait_shm_fd; | |
708 | struct sigaction act; | |
fb50c39d | 709 | mode_t old_umask = 0; |
b0a99af4 MD |
710 | const char *outputpath; |
711 | const char **event_names; | |
712 | unsigned int nr_events; | |
713 | ||
714 | if (argc < 2) { | |
715 | printf("Usage:\n"); | |
716 | printf("%s outputpath event_name1 event_name2 ...\n", | |
717 | argv[0]); | |
718 | exit(-1); | |
719 | } | |
720 | outputpath = argv[1]; | |
721 | event_names = &argv[2]; | |
722 | nr_events = argc - 2; | |
723 | ||
724 | set_ulimit(); | |
725 | ||
726 | /* Ignore sigpipe */ | |
727 | memset(&act, 0, sizeof(act)); | |
728 | ret = sigemptyset(&act.sa_mask); | |
729 | if (ret == -1) { | |
730 | perror("sigemptyset"); | |
731 | return -1; | |
732 | } | |
733 | ||
734 | act.sa_handler = SIG_IGN; | |
735 | ret = sigaction(SIGPIPE, &act, NULL); | |
736 | if (ret == -1) { | |
737 | perror("sigaction"); | |
738 | return -1; | |
739 | } | |
740 | ||
741 | /* Handle SIGTERM */ | |
742 | act.sa_handler = handle_signals; | |
743 | ret = sigaction(SIGTERM, &act, NULL); | |
744 | if (ret == -1) { | |
745 | perror("sigaction"); | |
746 | return -1; | |
747 | } | |
748 | /* Handle SIGINT */ | |
749 | ret = sigaction(SIGINT, &act, NULL); | |
750 | if (ret == -1) { | |
751 | perror("sigaction"); | |
752 | return -1; | |
753 | } | |
754 | ||
755 | if (geteuid() == 0) { | |
756 | ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH); | |
757 | if (ret && errno != EEXIST) { | |
758 | perror("mkdir"); | |
759 | return -1; | |
760 | } | |
761 | wait_shm_fd = get_wait_shm(DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH, | |
762 | sysconf(_SC_PAGE_SIZE), 1); | |
763 | if (wait_shm_fd < 0) { | |
764 | perror("global wait shm error"); | |
765 | return -1; | |
766 | } | |
767 | strcpy(apps_sock_path, DEFAULT_GLOBAL_APPS_UNIX_SOCK); | |
768 | old_umask = umask(0); | |
769 | } else { | |
770 | snprintf(local_apps_wait_shm_path, PATH_MAX, | |
771 | DEFAULT_HOME_APPS_WAIT_SHM_PATH, getuid()); | |
772 | wait_shm_fd = get_wait_shm(local_apps_wait_shm_path, | |
773 | sysconf(_SC_PAGE_SIZE), 0); | |
774 | if (wait_shm_fd < 0) { | |
775 | perror("local wait shm error"); | |
776 | return -1; | |
777 | } | |
778 | home_dir = (const char *) getenv("HOME"); | |
779 | if (!home_dir) { | |
780 | perror("getenv error"); | |
781 | return -ENOENT; | |
782 | } | |
783 | snprintf(apps_sock_path, PATH_MAX, | |
784 | DEFAULT_HOME_APPS_UNIX_SOCK, home_dir); | |
785 | } | |
786 | ||
57773204 | 787 | ret = ustcomm_create_unix_sock(apps_sock_path); |
b0a99af4 MD |
788 | if (ret < 0) { |
789 | perror("create error"); | |
790 | return ret; | |
791 | } | |
792 | apps_socket = ret; | |
793 | ||
794 | if (getuid() == 0) { | |
795 | /* File permission MUST be 666 */ | |
796 | ret = chmod(apps_sock_path, | |
797 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); | |
798 | if (ret < 0) { | |
799 | printf("Set file permissions failed: %s\n", apps_sock_path); | |
800 | perror("chmod"); | |
801 | goto end; | |
802 | } | |
803 | umask(old_umask); | |
804 | } | |
57773204 | 805 | ret = ustcomm_listen_unix_sock(apps_socket); |
b0a99af4 MD |
806 | if (ret < 0) { |
807 | perror("listen error"); | |
808 | return ret; | |
809 | } | |
810 | ||
811 | /* wake up futexes */ | |
812 | ret = update_futex(wait_shm_fd, 1); | |
813 | if (ret) { | |
814 | fprintf(stderr, "Error wakeup futex\n"); | |
815 | return -1; | |
816 | } | |
817 | ||
818 | for (;;) { | |
819 | int sock; | |
820 | ssize_t len; | |
821 | struct { | |
822 | uint32_t major; | |
823 | uint32_t minor; | |
824 | pid_t pid; | |
825 | pid_t ppid; | |
826 | uid_t uid; | |
827 | gid_t gid; | |
828 | char name[16]; /* Process name */ | |
829 | } reg_msg; | |
830 | char bufname[17]; | |
831 | ||
832 | if (quit_program) | |
833 | break; | |
834 | ||
835 | printf("Accepting application registration\n"); | |
57773204 | 836 | sock = ustcomm_accept_unix_sock(apps_socket); |
b0a99af4 MD |
837 | if (sock < 0) { |
838 | perror("accept error"); | |
839 | goto end; | |
840 | } | |
841 | ||
842 | /* | |
843 | * Basic recv here to handle the very simple data | |
844 | * that the libust send to register (reg_msg). | |
845 | */ | |
57773204 | 846 | len = ustcomm_recv_unix_sock(sock, ®_msg, sizeof(reg_msg)); |
b0a99af4 | 847 | if (len < 0 || len != sizeof(reg_msg)) { |
57773204 | 848 | perror("ustcomm_recv_unix_sock"); |
b0a99af4 MD |
849 | continue; |
850 | } | |
851 | memcpy(bufname, reg_msg.name, 16); | |
852 | bufname[16] = '\0'; | |
853 | printf("Application %s pid %u ppid %u uid %u gid %u has registered (version : %u.%u)\n", | |
854 | bufname, reg_msg.pid, reg_msg.ppid, reg_msg.uid, | |
855 | reg_msg.gid, reg_msg.major, reg_msg.minor); | |
856 | ret = send_app_msgs(sock, outputpath, nr_events, event_names); | |
857 | if (ret) { | |
858 | printf("Error in send_app_msgs.\n"); | |
859 | sleep(1); | |
860 | } | |
861 | close(sock); | |
862 | } | |
863 | ||
864 | end: | |
865 | printf("quitting.\n"); | |
866 | /* Let applications know we are not responding anymore */ | |
867 | ret = update_futex(wait_shm_fd, 0); | |
868 | if (ret) { | |
869 | fprintf(stderr, "Error wakeup futex\n"); | |
870 | return -1; | |
871 | } | |
872 | ||
873 | return 0; | |
874 | } |