Commit | Line | Data |
---|---|---|
826d496d MD |
1 | /* |
2 | * Copyright (c) 2011 David Goulet <david.goulet@polymtl.ca> | |
fac6795d DG |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along | |
15 | * with this program; if not, write to the Free Software Foundation, Inc., | |
16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
fac6795d DG |
17 | */ |
18 | ||
19 | #define _GNU_SOURCE | |
fac6795d | 20 | #include <getopt.h> |
f3ed775e | 21 | #include <signal.h> |
fac6795d DG |
22 | #include <stdio.h> |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
fac6795d DG |
25 | #include <unistd.h> |
26 | ||
5b97ec60 | 27 | #include <lttng/lttng.h> |
fac6795d | 28 | |
f3ed775e | 29 | #include "cmd.h" |
beb8c75a | 30 | #include "conf.h" |
fac6795d DG |
31 | #include "lttngerr.h" |
32 | ||
33 | /* Variables */ | |
34 | static char *progname; | |
fac6795d | 35 | |
f3ed775e DG |
36 | int opt_quiet; |
37 | int opt_verbose; | |
38 | static int opt_no_sessiond; | |
39 | static char *opt_sessiond_path; | |
40 | ||
41 | enum { | |
42 | OPT_NO_SESSIOND, | |
43 | OPT_SESSION_PATH, | |
44 | }; | |
45 | ||
46 | /* Getopt options. No first level command. */ | |
47 | static struct option long_options[] = { | |
48 | {"help", 0, NULL, 'h'}, | |
49 | {"group", 1, NULL, 'g'}, | |
50 | {"verbose", 0, NULL, 'v'}, | |
51 | {"quiet", 0, NULL, 'q'}, | |
52 | {"no-sessiond", 0, NULL, OPT_NO_SESSIOND}, | |
53 | {"sessiond-path", 1, NULL, OPT_SESSION_PATH}, | |
54 | {NULL, 0, NULL, 0} | |
55 | }; | |
56 | ||
57 | /* First level command */ | |
58 | static struct cmd_struct commands[] = { | |
59 | { "list", cmd_list}, | |
60 | { "create", cmd_create}, | |
61 | { "destroy", cmd_destroy}, | |
62 | { "add-channel", cmd_add_channel}, | |
63 | { "start", cmd_start}, | |
64 | { "stop", cmd_stop}, | |
65 | { "enable-event", cmd_enable_events}, | |
66 | { NULL, NULL} /* Array closure */ | |
67 | }; | |
68 | ||
69 | static void usage(FILE *ofp) | |
8c0faa1d | 70 | { |
f3ed775e DG |
71 | fprintf(ofp, "LTTng Trace Control " VERSION"\n\n"); |
72 | fprintf(ofp, "usage: lttng [options] <command>\n"); | |
73 | fprintf(ofp, "\n"); | |
74 | fprintf(ofp, "Options:\n"); | |
75 | fprintf(ofp, " -h, --help Show this help\n"); | |
76 | fprintf(ofp, " -g, --group NAME Unix tracing group name. (default: tracing)\n"); | |
77 | fprintf(ofp, " -v, --verbose Verbose mode\n"); | |
78 | fprintf(ofp, " -q, --quiet Quiet mode\n"); | |
79 | fprintf(ofp, " --no-sessiond Don't spawn a session daemon\n"); | |
80 | fprintf(ofp, " --sessiond-path Session daemon full path\n"); | |
81 | fprintf(ofp, "\n"); | |
82 | fprintf(ofp, "Commands:\n"); | |
83 | fprintf(ofp, " add-channel Add channel to tracer\n"); | |
84 | fprintf(ofp, " create Create tracing session\n"); | |
85 | fprintf(ofp, " destroy Teardown tracing session\n"); | |
86 | fprintf(ofp, " enable-event Enable tracing event\n"); | |
87 | fprintf(ofp, " disable-event Disable tracing event\n"); | |
88 | fprintf(ofp, " list List possible tracing options\n"); | |
89 | fprintf(ofp, " start Start tracing\n"); | |
90 | fprintf(ofp, " stop Stop tracing\n"); | |
91 | fprintf(ofp, " version Show version information\n"); | |
92 | fprintf(ofp, "\n"); | |
93 | fprintf(ofp, "Please see the lttng(1) man page for full documentation.\n"); | |
94 | fprintf(ofp, "See http://lttng.org for updates, bug reports and news.\n"); | |
8c0faa1d DG |
95 | } |
96 | ||
7442b2ba | 97 | /* |
f3ed775e | 98 | * clean_exit |
96243366 | 99 | */ |
f3ed775e | 100 | static void clean_exit(int code) |
96243366 | 101 | { |
f3ed775e DG |
102 | DBG("Clean exit"); |
103 | exit(code); | |
894be886 | 104 | } |
96243366 | 105 | |
894be886 | 106 | /* |
f3ed775e | 107 | * sighandler |
2ef84c95 | 108 | * |
f3ed775e | 109 | * Signal handler for the daemon |
2ef84c95 | 110 | */ |
f3ed775e | 111 | static void sighandler(int sig) |
2ef84c95 | 112 | { |
f3ed775e DG |
113 | switch (sig) { |
114 | case SIGTERM: | |
115 | DBG("SIGTERM catched"); | |
116 | clean_exit(EXIT_FAILURE); | |
117 | break; | |
118 | case SIGCHLD: | |
119 | /* Notify is done */ | |
120 | DBG("SIGCHLD catched"); | |
121 | break; | |
122 | default: | |
123 | DBG("Unknown signal %d catched", sig); | |
124 | break; | |
2ef84c95 DG |
125 | } |
126 | ||
f3ed775e | 127 | return; |
2ef84c95 DG |
128 | } |
129 | ||
130 | /* | |
f3ed775e | 131 | * set_signal_handler |
894be886 | 132 | * |
f3ed775e | 133 | * Setup signal handler for SIGCHLD and SIGTERM. |
894be886 | 134 | */ |
f3ed775e | 135 | static int set_signal_handler(void) |
894be886 | 136 | { |
f3ed775e DG |
137 | int ret = 0; |
138 | struct sigaction sa; | |
139 | sigset_t sigset; | |
33a2b854 | 140 | |
f3ed775e DG |
141 | if ((ret = sigemptyset(&sigset)) < 0) { |
142 | perror("sigemptyset"); | |
33a2b854 DG |
143 | goto end; |
144 | } | |
145 | ||
f3ed775e DG |
146 | sa.sa_handler = sighandler; |
147 | sa.sa_mask = sigset; | |
148 | sa.sa_flags = 0; | |
149 | if ((ret = sigaction(SIGCHLD, &sa, NULL)) < 0) { | |
150 | perror("sigaction"); | |
96243366 DG |
151 | goto end; |
152 | } | |
153 | ||
f3ed775e DG |
154 | if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { |
155 | perror("sigaction"); | |
156 | goto end; | |
894be886 DG |
157 | } |
158 | ||
96243366 | 159 | end: |
57167058 DG |
160 | return ret; |
161 | } | |
162 | ||
fac6795d | 163 | /* |
f3ed775e | 164 | * handle_command |
fac6795d | 165 | * |
f3ed775e DG |
166 | * Handle the full argv list of a first level command. Will find the command |
167 | * in the global commands array and call the function callback associated. | |
1c9f7941 | 168 | * |
f3ed775e DG |
169 | * If command not found, return -1 |
170 | * else, return function command error code. | |
1c9f7941 | 171 | */ |
f3ed775e | 172 | static int handle_command(int argc, char **argv) |
1c9f7941 | 173 | { |
f3ed775e DG |
174 | int i = 0, ret; |
175 | struct cmd_struct *cmd; | |
1c9f7941 | 176 | |
f3ed775e DG |
177 | if (*argv == NULL) { |
178 | ret = CMD_SUCCESS; | |
47b74d63 | 179 | goto end; |
1c9f7941 DG |
180 | } |
181 | ||
f3ed775e DG |
182 | cmd = &commands[i]; |
183 | while (cmd->func != NULL) { | |
184 | /* Find command */ | |
185 | if (strcmp(argv[0], cmd->name) == 0) { | |
186 | ret = cmd->func(argc, (const char**) argv); | |
187 | switch (ret) { | |
188 | case CMD_ERROR: | |
189 | ERR("Command error"); | |
190 | break; | |
191 | case CMD_NOT_IMPLEMENTED: | |
192 | ERR("Options not implemented"); | |
193 | break; | |
194 | case CMD_UNDEFINED: | |
195 | ERR("Undefined command"); | |
196 | break; | |
197 | case CMD_FATAL: | |
198 | ERR("Fatal error"); | |
199 | break; | |
200 | } | |
201 | goto end; | |
894be886 | 202 | } |
f3ed775e DG |
203 | i++; |
204 | cmd = &commands[i]; | |
894be886 DG |
205 | } |
206 | ||
f3ed775e DG |
207 | /* Command not found */ |
208 | ret = -1; | |
894be886 DG |
209 | |
210 | end: | |
f3ed775e | 211 | return ret; |
8548ff30 DG |
212 | } |
213 | ||
5b8719f5 DG |
214 | /* |
215 | * spawn_sessiond | |
216 | * | |
217 | * Spawn a session daemon by forking and execv. | |
218 | */ | |
219 | static int spawn_sessiond(char *pathname) | |
220 | { | |
221 | int ret = 0; | |
222 | pid_t pid; | |
223 | ||
f3ed775e | 224 | MSG("Spawning a session daemon"); |
5b8719f5 DG |
225 | pid = fork(); |
226 | if (pid == 0) { | |
5e16da05 MD |
227 | /* |
228 | * Spawn session daemon and tell | |
5b8719f5 DG |
229 | * it to signal us when ready. |
230 | */ | |
5e16da05 MD |
231 | execlp(pathname, "ltt-sessiond", "--sig-parent", "--quiet", NULL); |
232 | /* execlp only returns if error happened */ | |
233 | if (errno == ENOENT) { | |
234 | ERR("No session daemon found. Use --sessiond-path."); | |
235 | } else { | |
236 | perror("execlp"); | |
5b8719f5 | 237 | } |
5e16da05 MD |
238 | kill(getppid(), SIGTERM); /* unpause parent */ |
239 | exit(EXIT_FAILURE); | |
5b8719f5 DG |
240 | } else if (pid > 0) { |
241 | /* Wait for ltt-sessiond to start */ | |
242 | pause(); | |
243 | goto end; | |
244 | } else { | |
245 | perror("fork"); | |
246 | ret = -1; | |
247 | goto end; | |
248 | } | |
249 | ||
250 | end: | |
251 | return ret; | |
252 | } | |
253 | ||
fac6795d | 254 | /* |
f3ed775e | 255 | * check_sessiond |
fac6795d DG |
256 | * |
257 | * Check if the session daemon is available using | |
5b8719f5 DG |
258 | * the liblttngctl API for the check. If not, try to |
259 | * spawn a daemon. | |
fac6795d | 260 | */ |
f3ed775e | 261 | static int check_sessiond(void) |
fac6795d DG |
262 | { |
263 | int ret; | |
5e16da05 | 264 | char *pathname = NULL, *alloc_pathname = NULL; |
fac6795d | 265 | |
947308c4 DG |
266 | ret = lttng_session_daemon_alive(); |
267 | if (ret == 0) { /* not alive */ | |
5b8719f5 DG |
268 | /* Try command line option path */ |
269 | if (opt_sessiond_path != NULL) { | |
270 | ret = access(opt_sessiond_path, F_OK | X_OK); | |
271 | if (ret < 0) { | |
272 | ERR("No such file: %s", opt_sessiond_path); | |
273 | goto end; | |
274 | } | |
275 | pathname = opt_sessiond_path; | |
276 | } else { | |
277 | /* Try LTTNG_SESSIOND_PATH env variable */ | |
e8f07c63 | 278 | pathname = getenv(LTTNG_SESSIOND_PATH_ENV); |
5b8719f5 DG |
279 | } |
280 | ||
281 | /* Let's rock and roll */ | |
282 | if (pathname == NULL) { | |
5e16da05 | 283 | ret = asprintf(&alloc_pathname, "ltt-sessiond"); |
5b8719f5 DG |
284 | if (ret < 0) { |
285 | goto end; | |
286 | } | |
5e16da05 | 287 | pathname = alloc_pathname; |
5b8719f5 DG |
288 | } |
289 | ||
290 | ret = spawn_sessiond(pathname); | |
5e16da05 | 291 | free(alloc_pathname); |
5b8719f5 DG |
292 | if (ret < 0) { |
293 | ERR("Problem occurs when starting %s", pathname); | |
294 | goto end; | |
295 | } | |
fac6795d DG |
296 | } |
297 | ||
5b8719f5 | 298 | end: |
fac6795d DG |
299 | return ret; |
300 | } | |
301 | ||
5b8719f5 | 302 | /* |
f3ed775e | 303 | * parse_args |
5b8719f5 | 304 | * |
f3ed775e DG |
305 | * Parse command line arguments. |
306 | * Return 0 if OK, else -1 | |
5b8719f5 | 307 | */ |
f3ed775e | 308 | static int parse_args(int argc, char **argv) |
5b8719f5 | 309 | { |
f3ed775e | 310 | int opt, ret; |
5b8719f5 | 311 | |
f3ed775e DG |
312 | if (argc < 2) { |
313 | usage(stderr); | |
314 | clean_exit(EXIT_FAILURE); | |
5b8719f5 DG |
315 | } |
316 | ||
f3ed775e DG |
317 | while ((opt = getopt_long(argc, argv, "+hvqg:", long_options, NULL)) != -1) { |
318 | switch (opt) { | |
319 | case 'h': | |
320 | usage(stderr); | |
321 | goto error; | |
322 | case 'v': | |
323 | opt_verbose = 1; | |
324 | break; | |
325 | case 'q': | |
326 | opt_quiet = 1; | |
327 | break; | |
328 | case 'g': | |
329 | lttng_set_tracing_group(optarg); | |
330 | break; | |
331 | case OPT_NO_SESSIOND: | |
332 | opt_no_sessiond = 1; | |
333 | break; | |
334 | case OPT_SESSION_PATH: | |
335 | opt_sessiond_path = strdup(optarg); | |
336 | break; | |
337 | default: | |
338 | usage(stderr); | |
339 | goto error; | |
340 | } | |
5b8719f5 | 341 | } |
fac6795d | 342 | |
f3ed775e DG |
343 | /* If both options are specified, quiet wins */ |
344 | if (opt_verbose && opt_quiet) { | |
345 | opt_verbose = 0; | |
5b8719f5 DG |
346 | } |
347 | ||
f3ed775e DG |
348 | /* Spawn session daemon if needed */ |
349 | if (opt_no_sessiond == 0 && (check_sessiond() < 0)) { | |
350 | goto error; | |
5b8719f5 DG |
351 | } |
352 | ||
f3ed775e DG |
353 | /* No leftovers, print usage and quit */ |
354 | if ((argc - optind) == 0) { | |
355 | usage(stderr); | |
356 | goto error; | |
357 | } | |
7442b2ba | 358 | |
f3ed775e DG |
359 | /* |
360 | * Handle leftovers which is a first level command with the trailing | |
361 | * options. | |
362 | */ | |
363 | ret = handle_command(argc - optind, argv + optind); | |
364 | if (ret < 0) { | |
365 | if (ret == -1) { | |
366 | usage(stderr); | |
367 | goto error; | |
368 | } else { | |
369 | ERR("%s", lttng_get_readable_code(ret)); | |
370 | } | |
96243366 DG |
371 | } |
372 | ||
f3ed775e DG |
373 | return ret; |
374 | ||
375 | error: | |
376 | return -1; | |
fac6795d DG |
377 | } |
378 | ||
f3ed775e | 379 | |
fac6795d | 380 | /* |
5b8719f5 | 381 | * main |
fac6795d DG |
382 | */ |
383 | int main(int argc, char *argv[]) | |
384 | { | |
385 | int ret; | |
386 | ||
387 | progname = argv[0] ? argv[0] : "lttng"; | |
388 | ||
389 | /* For Mathieu Desnoyers aka Dr Tracing */ | |
390 | if (strncmp(progname, "drtrace", 7) == 0) { | |
391 | MSG("%c[%d;%dmWelcome back Dr Tracing!%c[%dm\n\n", 27,1,33,27,0); | |
392 | } | |
393 | ||
5b8719f5 DG |
394 | ret = set_signal_handler(); |
395 | if (ret < 0) { | |
87378cf5 | 396 | clean_exit(ret); |
5b8719f5 DG |
397 | } |
398 | ||
f3ed775e DG |
399 | ret = parse_args(argc, argv); |
400 | clean_exit(ret); | |
87378cf5 | 401 | |
fac6795d DG |
402 | return 0; |
403 | } |