Commit | Line | Data |
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f248b7d8 JD |
1 | #define _GNU_SOURCE /* See feature_test_macros(7) */ |
2 | #include <stdlib.h> | |
3 | #include <unistd.h> | |
4 | #include <sys/types.h> | |
5 | #include <stdio.h> | |
6 | #include <stdint.h> | |
7 | #include <inttypes.h> | |
8 | ||
9 | #define event_list "lttng_statedump_start,lttng_statedump_end," \ | |
10 | "lttng_statedump_process_state,lttng_statedump_file_descriptor," \ | |
11 | "lttng_statedump_vm_map,lttng_statedump_network_interface," \ | |
12 | "lttng_statedump_interrupt,sched_process_free," \ | |
13 | "sched_switch,sched_process_fork" | |
14 | #define context_list "-t pid -t procname -t tid -t ppid " | |
15 | ||
16 | static | |
17 | int check_or_start_sessiond() | |
18 | { | |
19 | int ret; | |
20 | int sudo = 0; | |
21 | ||
22 | ret = system("pgrep -u root lttng-sessiond >/dev/null"); | |
23 | if (ret == 0) | |
24 | goto end; | |
25 | ||
26 | if (getuid() != 0) { | |
27 | fprintf(stderr, "Trying to start lttng-sessiond with sudo\n"); | |
28 | ret = system("sudo -l lttng-sessiond >/dev/null"); | |
29 | if (ret < 0) { | |
30 | fprintf(stderr, "[error] You are not root and not " | |
31 | "allowed by sudo to start lttng-sessiond\n"); | |
32 | ret = -1; | |
33 | goto end; | |
34 | } | |
35 | sudo = 1; | |
36 | } | |
37 | ||
38 | if (sudo) | |
39 | ret = system("sudo lttng-sessiond -d"); | |
40 | else | |
41 | ret = system("lttng-sessiond -d"); | |
42 | ||
43 | if (ret != 0) { | |
44 | fprintf(stderr, "Error starting lttng-sessiond as root\n"); | |
45 | ret = -1; | |
46 | goto end; | |
47 | } | |
48 | ||
49 | end: | |
50 | return ret; | |
51 | } | |
52 | ||
53 | static | |
54 | int check_or_start_relayd() | |
55 | { | |
56 | int ret; | |
57 | ||
58 | ret = system("pgrep lttng-relayd >/dev/null"); | |
59 | if (ret == 0) | |
60 | goto end; | |
61 | ||
62 | ret = system("lttng-relayd -d"); | |
63 | if (ret != 0) { | |
64 | fprintf(stderr, "Error starting lttng-relayd\n"); | |
65 | ret = -1; | |
66 | goto end; | |
67 | } | |
68 | ||
69 | end: | |
70 | return ret; | |
71 | } | |
72 | ||
73 | /* | |
74 | * Return 0 if in tracing group or root, 1 if sudo is needed (and working), | |
75 | * a negative value on error. | |
76 | */ | |
77 | static | |
78 | int check_tracing_group() | |
79 | { | |
80 | int ret; | |
81 | ||
82 | ret = getuid(); | |
83 | if (ret == 0) | |
84 | goto end; | |
85 | ||
86 | ret = system("groups|grep tracing >/dev/null"); | |
87 | if (ret == 0) { | |
88 | goto end; | |
89 | } | |
90 | ||
91 | ret = system("sudo lttng --version >/dev/null"); | |
92 | if (ret != 0) { | |
93 | fprintf(stderr, "Error executing lttng with sudo, you need to " | |
94 | "be root or in the \"tracing\" group to start " | |
95 | "kernel tracing\n"); | |
96 | ret = -1; | |
97 | goto end; | |
98 | } else { | |
99 | ret = 1; | |
100 | } | |
101 | ||
102 | end: | |
103 | return ret; | |
104 | } | |
105 | ||
106 | static | |
107 | int check_lttng_modules(int sudo) | |
108 | { | |
109 | int ret; | |
110 | ||
111 | if (sudo) { | |
112 | ret = system("sudo lttng list -k | grep sched_switch >/dev/null"); | |
113 | } else { | |
114 | ret = system("lttng list -k | grep sched_switch >/dev/null"); | |
115 | } | |
116 | if (ret != 0) { | |
117 | fprintf(stderr, "Error listing kernel events, " | |
118 | "lttng-modules might not be installed\n"); | |
119 | goto end; | |
120 | } | |
121 | ||
122 | end: | |
123 | return ret; | |
124 | } | |
125 | ||
126 | static | |
127 | int check_requirements(int *sudo) | |
128 | { | |
129 | int ret; | |
130 | ||
131 | ret = check_or_start_sessiond(); | |
132 | if (ret < 0) | |
133 | goto end; | |
134 | ret = check_or_start_relayd(); | |
135 | if (ret < 0) | |
136 | goto end; | |
137 | ret = check_tracing_group(); | |
138 | if (ret < 0) | |
139 | goto end; | |
140 | else if (ret == 1) | |
141 | *sudo = 1; | |
142 | ||
143 | ret = check_lttng_modules(*sudo); | |
144 | if (ret < 0) | |
145 | goto end; | |
146 | end: | |
147 | return ret; | |
148 | } | |
149 | ||
150 | /* | |
151 | * Allocate a random string, must be freed by the caller. | |
152 | */ | |
153 | static | |
154 | char *random_session_name() | |
155 | { | |
156 | uint64_t id; | |
157 | char *str = NULL; | |
158 | int ret; | |
159 | ||
160 | FILE *f = fopen( "/dev/urandom", "r"); | |
161 | if (!f) { | |
162 | perror("fopen"); | |
163 | goto end; | |
164 | } | |
165 | ||
166 | ret = fread(&id, 1, sizeof(uint64_t), f); | |
167 | if (ret < sizeof(id)) { | |
168 | perror("fread"); | |
169 | goto end; | |
170 | } | |
171 | ||
172 | ret = asprintf(&str, "lttngtop-%" PRIu64, id); | |
173 | if (ret < 0) { | |
174 | fprintf(stderr, "Error allocating session name"); | |
175 | str = NULL; | |
176 | goto end; | |
177 | } | |
178 | ||
179 | ret = fclose(f); | |
180 | if (ret != 0) { | |
181 | perror("fclose"); | |
182 | goto end; | |
183 | } | |
184 | ||
185 | end: | |
186 | return str; | |
187 | } | |
188 | ||
189 | static | |
190 | int check_session_name(char *name, int sudo) | |
191 | { | |
192 | int ret; | |
193 | char cmd[1024]; | |
194 | ||
195 | ret = sprintf(cmd, "%s lttng list | grep %s >/dev/null", | |
196 | (sudo) ? "sudo" : " ", name); | |
197 | if (ret < 0) { | |
198 | fprintf(stderr, "Allocating cmd\n"); | |
199 | goto end; | |
200 | } | |
201 | ||
202 | ret = (system(cmd)); | |
203 | if (ret == 0) { | |
204 | fprintf(stderr, "Error: session %s already exist, either we " | |
205 | "are not random enough or something is " | |
206 | "really wrong\n", name); | |
207 | ret = -1; | |
208 | goto end; | |
209 | } | |
210 | ||
211 | end: | |
212 | return ret; | |
213 | } | |
214 | ||
215 | static | |
216 | int local_session(char *name, int sudo) | |
217 | { | |
218 | int ret; | |
219 | char cmd[1024]; | |
220 | ||
221 | ret = sprintf(cmd, "%s lttng create %s >/dev/null", | |
222 | (sudo) ? "sudo" : " ", name); | |
223 | if (ret < 0) { | |
224 | fprintf(stderr, "Allocating cmd\n"); | |
225 | goto end; | |
226 | } | |
227 | ret = (system(cmd)); | |
228 | if (ret != 0) { | |
229 | fprintf(stderr, "Error: creating the session\n"); | |
230 | ret = -1; | |
231 | goto end; | |
232 | } | |
233 | ||
234 | end: | |
235 | return ret; | |
236 | } | |
237 | ||
238 | static | |
239 | int enable_event(char *name, int sudo) | |
240 | { | |
241 | int ret; | |
242 | char cmd[1024]; | |
243 | ||
244 | ret = sprintf(cmd, "%s lttng enable-event -s %s -k %s >/dev/null", | |
245 | (sudo) ? "sudo" : " ", name, event_list); | |
246 | if (ret < 0) { | |
247 | fprintf(stderr, "Allocating cmd\n"); | |
248 | goto end; | |
249 | } | |
250 | ||
251 | ret = (system(cmd)); | |
252 | if (ret != 0) { | |
253 | fprintf(stderr, "Error: enabling events\n"); | |
254 | ret = -1; | |
255 | goto end; | |
256 | } | |
257 | ||
258 | end: | |
259 | return ret; | |
260 | } | |
261 | ||
262 | static | |
263 | int add_contexts(char *name, int sudo) | |
264 | { | |
265 | int ret; | |
266 | char cmd[1024]; | |
267 | ||
268 | ret = sprintf(cmd, "%s lttng add-context -s %s -k %s >/dev/null", | |
269 | (sudo) ? "sudo" : " ", name, context_list); | |
270 | if (ret < 0) { | |
271 | fprintf(stderr, "allocating cmd\n"); | |
272 | goto end; | |
273 | } | |
274 | ||
275 | ret = (system(cmd)); | |
276 | if (ret != 0) { | |
277 | fprintf(stderr, "error: adding contexts\n"); | |
278 | ret = -1; | |
279 | goto end; | |
280 | } | |
281 | ||
282 | end: | |
283 | return ret; | |
284 | } | |
285 | ||
286 | static | |
287 | int start(char *name, int sudo) | |
288 | { | |
289 | int ret; | |
290 | char cmd[1024]; | |
291 | ||
292 | ret = sprintf(cmd, "%s lttng start %s >/dev/null", | |
293 | (sudo) ? "sudo" : " ", name); | |
294 | if (ret < 0) { | |
295 | fprintf(stderr, "allocating cmd\n"); | |
296 | goto end; | |
297 | } | |
298 | ||
299 | ret = (system(cmd)); | |
300 | if (ret != 0) { | |
301 | fprintf(stderr, "error: starting the session %s\n", name); | |
302 | ret = -1; | |
303 | goto end; | |
304 | } | |
305 | ||
306 | ret = sprintf(cmd, "%s lttng list|grep %s|cut -d'(' -f2|cut -d ')' -f1", | |
307 | (sudo) ? "sudo" : " ", name); | |
308 | if (ret < 0) { | |
309 | fprintf(stderr, "allocating cmd\n"); | |
310 | goto end; | |
311 | } | |
312 | fprintf(stderr, "Local session started in "); | |
313 | ret = (system(cmd)); | |
314 | if (ret != 0) { | |
315 | fprintf(stderr, "error: listing the sessions\n"); | |
316 | ret = -1; | |
317 | goto end; | |
318 | } | |
319 | ||
320 | end: | |
321 | return ret; | |
322 | } | |
323 | ||
324 | static | |
325 | int destroy(char *name, int sudo) | |
326 | { | |
327 | int ret; | |
328 | char cmd[1024]; | |
329 | ||
330 | ret = sprintf(cmd, "%s lttng destroy %s >/dev/null", | |
331 | (sudo) ? "sudo" : " ", name); | |
332 | if (ret < 0) { | |
333 | fprintf(stderr, "allocating cmd\n"); | |
334 | goto end; | |
335 | } | |
336 | ||
337 | ret = (system(cmd)); | |
338 | if (ret != 0) { | |
339 | fprintf(stderr, "error: destroying the session %s\n", name); | |
340 | ret = -1; | |
341 | goto end; | |
342 | } | |
343 | ||
344 | end: | |
345 | return ret; | |
346 | } | |
347 | ||
348 | int create_local_session() | |
349 | { | |
350 | int ret; | |
351 | char *name; | |
352 | int sudo = 0; | |
353 | ||
354 | ret = check_requirements(&sudo); | |
355 | ||
356 | name = random_session_name(); | |
357 | if (!name) { | |
358 | ret = -1; | |
359 | goto end; | |
360 | } | |
361 | ||
362 | ret = check_session_name(name, sudo); | |
363 | if (ret < 0) { | |
364 | goto end_free; | |
365 | } | |
366 | ||
367 | ret = local_session(name, sudo); | |
368 | if (ret < 0) { | |
369 | goto end_free; | |
370 | } | |
371 | ||
372 | ret = enable_event(name, sudo); | |
373 | if (ret < 0) { | |
374 | goto end_free; | |
375 | } | |
376 | ||
377 | ret = add_contexts(name, sudo); | |
378 | if (ret < 0) { | |
379 | goto end_free; | |
380 | } | |
381 | ||
382 | ret = start(name, sudo); | |
383 | if (ret < 0) { | |
384 | goto end_free; | |
385 | } | |
386 | ||
387 | end_free: | |
388 | free(name); | |
389 | end: | |
390 | return ret; | |
391 | } | |
392 | ||
393 | int destroy_local_session(char *name, int sudo) | |
394 | { | |
395 | return destroy(name, sudo); | |
396 | } | |
397 | ||
398 | /* | |
399 | int create_live_local_session(); | |
400 | int destroy_live_local_session(); | |
401 | */ |