| 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 | #include <string.h> |
| 9 | |
| 10 | #define event_list "lttng_statedump_start,lttng_statedump_end," \ |
| 11 | "lttng_statedump_process_state,lttng_statedump_file_descriptor," \ |
| 12 | "lttng_statedump_vm_map,lttng_statedump_network_interface," \ |
| 13 | "lttng_statedump_interrupt,sched_process_free," \ |
| 14 | "sched_switch,sched_process_fork" |
| 15 | #define context_list "-t pid -t procname -t tid -t ppid " |
| 16 | |
| 17 | static |
| 18 | int check_or_start_sessiond() |
| 19 | { |
| 20 | int ret; |
| 21 | int sudo = 0; |
| 22 | |
| 23 | ret = system("pgrep -u root lttng-sessiond >/dev/null"); |
| 24 | if (ret == 0) |
| 25 | goto end; |
| 26 | |
| 27 | if (getuid() != 0) { |
| 28 | fprintf(stderr, "Trying to start lttng-sessiond with sudo\n"); |
| 29 | ret = system("sudo -l lttng-sessiond >/dev/null"); |
| 30 | if (ret < 0) { |
| 31 | fprintf(stderr, "[error] You are not root and not " |
| 32 | "allowed by sudo to start lttng-sessiond\n"); |
| 33 | ret = -1; |
| 34 | goto end; |
| 35 | } |
| 36 | ret = system("sudo -l lttng >/dev/null"); |
| 37 | if (ret < 0) { |
| 38 | fprintf(stderr, "[error] You are not root and not " |
| 39 | "allowed by sudo to use lttng\n"); |
| 40 | ret = -1; |
| 41 | goto end; |
| 42 | } |
| 43 | sudo = 1; |
| 44 | } |
| 45 | |
| 46 | if (sudo) |
| 47 | ret = system("sudo lttng-sessiond -d"); |
| 48 | else |
| 49 | ret = system("lttng-sessiond -d"); |
| 50 | |
| 51 | if (ret != 0) { |
| 52 | fprintf(stderr, "Error starting lttng-sessiond as root\n"); |
| 53 | ret = -1; |
| 54 | goto end; |
| 55 | } |
| 56 | |
| 57 | end: |
| 58 | return ret; |
| 59 | } |
| 60 | |
| 61 | static |
| 62 | int check_or_start_relayd() |
| 63 | { |
| 64 | int ret; |
| 65 | |
| 66 | ret = system("pgrep lttng-relayd >/dev/null"); |
| 67 | if (ret == 0) |
| 68 | goto end; |
| 69 | |
| 70 | ret = system("lttng-relayd -d"); |
| 71 | if (ret != 0) { |
| 72 | fprintf(stderr, "Error starting lttng-relayd\n"); |
| 73 | ret = -1; |
| 74 | goto end; |
| 75 | } |
| 76 | |
| 77 | end: |
| 78 | return ret; |
| 79 | } |
| 80 | |
| 81 | /* |
| 82 | * Return 0 if in tracing group or root, 1 if sudo is needed (and working), |
| 83 | * a negative value on error. |
| 84 | */ |
| 85 | static |
| 86 | int check_tracing_group() |
| 87 | { |
| 88 | int ret; |
| 89 | |
| 90 | ret = getuid(); |
| 91 | if (ret == 0) |
| 92 | goto end; |
| 93 | |
| 94 | ret = system("groups|grep tracing >/dev/null"); |
| 95 | if (ret == 0) { |
| 96 | goto end; |
| 97 | } |
| 98 | |
| 99 | ret = system("sudo lttng --version >/dev/null"); |
| 100 | if (ret != 0) { |
| 101 | fprintf(stderr, "Error executing lttng with sudo, you need to " |
| 102 | "be root or in the \"tracing\" group to start " |
| 103 | "kernel tracing\n"); |
| 104 | ret = -1; |
| 105 | goto end; |
| 106 | } else { |
| 107 | ret = 1; |
| 108 | } |
| 109 | |
| 110 | end: |
| 111 | return ret; |
| 112 | } |
| 113 | |
| 114 | static |
| 115 | int check_lttng_modules(int sudo) |
| 116 | { |
| 117 | int ret; |
| 118 | |
| 119 | if (sudo) { |
| 120 | ret = system("sudo lttng list -k | grep sched_switch >/dev/null"); |
| 121 | } else { |
| 122 | ret = system("lttng list -k | grep sched_switch >/dev/null"); |
| 123 | } |
| 124 | if (ret != 0) { |
| 125 | fprintf(stderr, "Error listing kernel events, " |
| 126 | "lttng-modules might not be installed\n"); |
| 127 | goto end; |
| 128 | } |
| 129 | |
| 130 | end: |
| 131 | return ret; |
| 132 | } |
| 133 | |
| 134 | static |
| 135 | int check_requirements(int *sudo) |
| 136 | { |
| 137 | int ret; |
| 138 | |
| 139 | ret = check_or_start_sessiond(); |
| 140 | if (ret < 0) |
| 141 | goto end; |
| 142 | ret = check_or_start_relayd(); |
| 143 | if (ret < 0) |
| 144 | goto end; |
| 145 | ret = check_tracing_group(); |
| 146 | if (ret < 0) |
| 147 | goto end; |
| 148 | else if (ret == 1) |
| 149 | *sudo = 1; |
| 150 | |
| 151 | ret = check_lttng_modules(*sudo); |
| 152 | if (ret < 0) |
| 153 | goto end; |
| 154 | end: |
| 155 | return ret; |
| 156 | } |
| 157 | |
| 158 | /* |
| 159 | * Allocate a random string, must be freed by the caller. |
| 160 | */ |
| 161 | static |
| 162 | char *random_session_name() |
| 163 | { |
| 164 | uint64_t id; |
| 165 | char *str = NULL; |
| 166 | int ret; |
| 167 | |
| 168 | FILE *f = fopen( "/dev/urandom", "r"); |
| 169 | if (!f) { |
| 170 | perror("fopen"); |
| 171 | goto end; |
| 172 | } |
| 173 | |
| 174 | ret = fread(&id, 1, sizeof(uint64_t), f); |
| 175 | if (ret < sizeof(id)) { |
| 176 | perror("fread"); |
| 177 | goto end; |
| 178 | } |
| 179 | |
| 180 | ret = asprintf(&str, "lttngtop-%" PRIu64, id); |
| 181 | if (ret < 0) { |
| 182 | fprintf(stderr, "Error allocating session name"); |
| 183 | str = NULL; |
| 184 | goto end; |
| 185 | } |
| 186 | |
| 187 | ret = fclose(f); |
| 188 | if (ret != 0) { |
| 189 | perror("fclose"); |
| 190 | goto end; |
| 191 | } |
| 192 | |
| 193 | end: |
| 194 | return str; |
| 195 | } |
| 196 | |
| 197 | static |
| 198 | int check_session_name(char *name, int sudo) |
| 199 | { |
| 200 | int ret; |
| 201 | char cmd[1024]; |
| 202 | |
| 203 | ret = sprintf(cmd, "%s lttng list | grep %s >/dev/null", |
| 204 | (sudo) ? "sudo" : " ", name); |
| 205 | if (ret < 0) { |
| 206 | fprintf(stderr, "Allocating cmd\n"); |
| 207 | goto end; |
| 208 | } |
| 209 | |
| 210 | ret = (system(cmd)); |
| 211 | if (ret == 0) { |
| 212 | fprintf(stderr, "Error: session %s already exist, either we " |
| 213 | "are not random enough or something is " |
| 214 | "really wrong\n", name); |
| 215 | ret = -1; |
| 216 | goto end; |
| 217 | } |
| 218 | |
| 219 | end: |
| 220 | return ret; |
| 221 | } |
| 222 | |
| 223 | static |
| 224 | int local_session(char *name, int sudo) |
| 225 | { |
| 226 | int ret; |
| 227 | char cmd[1024]; |
| 228 | |
| 229 | ret = sprintf(cmd, "%s lttng create %s >/dev/null", |
| 230 | (sudo) ? "sudo" : " ", name); |
| 231 | if (ret < 0) { |
| 232 | fprintf(stderr, "Allocating cmd\n"); |
| 233 | goto end; |
| 234 | } |
| 235 | ret = (system(cmd)); |
| 236 | if (ret != 0) { |
| 237 | fprintf(stderr, "Error: creating the session\n"); |
| 238 | ret = -1; |
| 239 | goto end; |
| 240 | } |
| 241 | |
| 242 | end: |
| 243 | return ret; |
| 244 | } |
| 245 | |
| 246 | static |
| 247 | int live_local_session(char *name, int sudo) |
| 248 | { |
| 249 | int ret; |
| 250 | char cmd[1024]; |
| 251 | |
| 252 | ret = sprintf(cmd, "%s lttng create %s --live 1000000 -U net://localhost >/dev/null", |
| 253 | (sudo) ? "sudo" : " ", name); |
| 254 | if (ret < 0) { |
| 255 | fprintf(stderr, "Allocating cmd\n"); |
| 256 | goto end; |
| 257 | } |
| 258 | ret = (system(cmd)); |
| 259 | if (ret != 0) { |
| 260 | fprintf(stderr, "Error: creating the session\n"); |
| 261 | ret = -1; |
| 262 | goto end; |
| 263 | } |
| 264 | |
| 265 | end: |
| 266 | return ret; |
| 267 | } |
| 268 | |
| 269 | static |
| 270 | int enable_events(char *name, int sudo) |
| 271 | { |
| 272 | int ret; |
| 273 | char cmd[1024]; |
| 274 | |
| 275 | ret = sprintf(cmd, "%s lttng enable-event -s %s -k %s >/dev/null;" |
| 276 | "lttng enable-event -k --syscall -a -s %s >/dev/null", |
| 277 | (sudo) ? "sudo" : " ", name, event_list, name); |
| 278 | if (ret < 0) { |
| 279 | fprintf(stderr, "Allocating cmd\n"); |
| 280 | goto end; |
| 281 | } |
| 282 | |
| 283 | ret = (system(cmd)); |
| 284 | if (ret != 0) { |
| 285 | fprintf(stderr, "Error: enabling events\n"); |
| 286 | ret = -1; |
| 287 | goto end; |
| 288 | } |
| 289 | |
| 290 | end: |
| 291 | return ret; |
| 292 | } |
| 293 | |
| 294 | static |
| 295 | int add_contexts(char *name, int sudo) |
| 296 | { |
| 297 | int ret; |
| 298 | char cmd[1024]; |
| 299 | |
| 300 | ret = sprintf(cmd, "%s lttng add-context -s %s -k %s >/dev/null", |
| 301 | (sudo) ? "sudo" : " ", name, context_list); |
| 302 | if (ret < 0) { |
| 303 | fprintf(stderr, "allocating cmd\n"); |
| 304 | goto end; |
| 305 | } |
| 306 | |
| 307 | ret = (system(cmd)); |
| 308 | if (ret != 0) { |
| 309 | fprintf(stderr, "error: adding contexts\n"); |
| 310 | ret = -1; |
| 311 | goto end; |
| 312 | } |
| 313 | |
| 314 | end: |
| 315 | return ret; |
| 316 | } |
| 317 | |
| 318 | static |
| 319 | int start(char *name, int sudo, int local, int print) |
| 320 | { |
| 321 | int ret; |
| 322 | char cmd[1024]; |
| 323 | |
| 324 | ret = sprintf(cmd, "%s lttng start %s >/dev/null", |
| 325 | (sudo) ? "sudo" : " ", name); |
| 326 | if (ret < 0) { |
| 327 | fprintf(stderr, "allocating cmd\n"); |
| 328 | goto end; |
| 329 | } |
| 330 | |
| 331 | ret = (system(cmd)); |
| 332 | if (ret != 0) { |
| 333 | fprintf(stderr, "error: starting the session %s\n", name); |
| 334 | ret = -1; |
| 335 | goto end; |
| 336 | } |
| 337 | |
| 338 | if (!print) |
| 339 | goto end; |
| 340 | |
| 341 | if (local) { |
| 342 | ret = sprintf(cmd, "%s lttng list|grep %s|cut -d'(' -f2|cut -d ')' -f1", |
| 343 | (sudo) ? "sudo" : " ", name); |
| 344 | } else { |
| 345 | ret = sprintf(cmd, "babeltrace -i lttng-live net://localhost|grep %s|cut -d' ' -f1", |
| 346 | name); |
| 347 | } |
| 348 | if (ret < 0) { |
| 349 | fprintf(stderr, "allocating cmd\n"); |
| 350 | goto end; |
| 351 | } |
| 352 | fprintf(stderr, "%s session started : ", |
| 353 | (local) ? "Local" : "Live"); |
| 354 | ret = (system(cmd)); |
| 355 | if (ret != 0) { |
| 356 | fprintf(stderr, "error: listing the sessions\n"); |
| 357 | ret = -1; |
| 358 | goto end; |
| 359 | } |
| 360 | |
| 361 | end: |
| 362 | return ret; |
| 363 | } |
| 364 | |
| 365 | static |
| 366 | char *live_path(char *name) |
| 367 | { |
| 368 | FILE *fp; |
| 369 | int ret; |
| 370 | char path[1035]; |
| 371 | char cmd[1024]; |
| 372 | char *out = NULL; |
| 373 | |
| 374 | ret = sprintf(cmd, "lttngtop -r net://localhost|grep %s|cut -d' ' -f1", |
| 375 | name); |
| 376 | if (ret < 0) { |
| 377 | fprintf(stderr, "allocating cmd\n"); |
| 378 | goto end; |
| 379 | } |
| 380 | |
| 381 | fp = popen(cmd, "r"); |
| 382 | if (fp == NULL) { |
| 383 | printf("Failed to run command\n" ); |
| 384 | goto end; |
| 385 | } |
| 386 | |
| 387 | /* Read the output a line at a time - output it. */ |
| 388 | out = fgets(path, sizeof(path)-1, fp); |
| 389 | if (out) |
| 390 | out = strdup(path); |
| 391 | |
| 392 | /* close */ |
| 393 | pclose(fp); |
| 394 | |
| 395 | end: |
| 396 | return out; |
| 397 | } |
| 398 | |
| 399 | static |
| 400 | int destroy(char *name) |
| 401 | { |
| 402 | int ret; |
| 403 | int sudo = 0; |
| 404 | char cmd[1024]; |
| 405 | |
| 406 | ret = system("groups|grep tracing >/dev/null"); |
| 407 | if (ret != 0 && getuid() != 0) { |
| 408 | ret = system("sudo -l lttng >/dev/null"); |
| 409 | if (ret < 0) { |
| 410 | fprintf(stderr, "[error] You are not root and not " |
| 411 | "allowed by sudo to use lttng\n"); |
| 412 | ret = -1; |
| 413 | goto end; |
| 414 | } |
| 415 | sudo = 1; |
| 416 | } |
| 417 | |
| 418 | ret = sprintf(cmd, "%s lttng destroy %s >/dev/null", |
| 419 | (sudo) ? "sudo" : " ", name); |
| 420 | if (ret < 0) { |
| 421 | fprintf(stderr, "allocating cmd\n"); |
| 422 | goto end; |
| 423 | } |
| 424 | |
| 425 | ret = (system(cmd)); |
| 426 | if (ret != 0) { |
| 427 | fprintf(stderr, "error: destroying the session %s\n", name); |
| 428 | ret = -1; |
| 429 | goto end; |
| 430 | } |
| 431 | |
| 432 | end: |
| 433 | return ret; |
| 434 | } |
| 435 | |
| 436 | int create_local_session() |
| 437 | { |
| 438 | int ret; |
| 439 | char *name; |
| 440 | int sudo = 0; |
| 441 | |
| 442 | ret = check_requirements(&sudo); |
| 443 | |
| 444 | name = random_session_name(); |
| 445 | if (!name) { |
| 446 | ret = -1; |
| 447 | goto end; |
| 448 | } |
| 449 | |
| 450 | ret = check_session_name(name, sudo); |
| 451 | if (ret < 0) { |
| 452 | goto end_free; |
| 453 | } |
| 454 | |
| 455 | ret = local_session(name, sudo); |
| 456 | if (ret < 0) { |
| 457 | goto end_free; |
| 458 | } |
| 459 | |
| 460 | ret = enable_events(name, sudo); |
| 461 | if (ret < 0) { |
| 462 | goto end_free; |
| 463 | } |
| 464 | |
| 465 | ret = add_contexts(name, sudo); |
| 466 | if (ret < 0) { |
| 467 | goto end_free; |
| 468 | } |
| 469 | |
| 470 | ret = start(name, sudo, 1, 1); |
| 471 | if (ret < 0) { |
| 472 | goto end_free; |
| 473 | } |
| 474 | |
| 475 | end_free: |
| 476 | free(name); |
| 477 | end: |
| 478 | return ret; |
| 479 | } |
| 480 | |
| 481 | int destroy_live_local_session(char *name) |
| 482 | { |
| 483 | return destroy(name); |
| 484 | } |
| 485 | |
| 486 | int create_live_local_session(char **session_path, char **session_name, int print) |
| 487 | { |
| 488 | int ret; |
| 489 | char *name; |
| 490 | int sudo = 0; |
| 491 | |
| 492 | ret = check_requirements(&sudo); |
| 493 | |
| 494 | name = random_session_name(); |
| 495 | if (!name) { |
| 496 | ret = -1; |
| 497 | goto end; |
| 498 | } |
| 499 | |
| 500 | ret = check_session_name(name, sudo); |
| 501 | if (ret < 0) { |
| 502 | goto end_free; |
| 503 | } |
| 504 | |
| 505 | ret = live_local_session(name, sudo); |
| 506 | if (ret < 0) { |
| 507 | goto end_free; |
| 508 | } |
| 509 | |
| 510 | ret = enable_events(name, sudo); |
| 511 | if (ret < 0) { |
| 512 | goto end_free; |
| 513 | } |
| 514 | |
| 515 | ret = add_contexts(name, sudo); |
| 516 | if (ret < 0) { |
| 517 | goto end_free; |
| 518 | } |
| 519 | |
| 520 | ret = start(name, sudo, 0, print); |
| 521 | if (ret < 0) { |
| 522 | goto end_free; |
| 523 | } |
| 524 | |
| 525 | if (session_path) |
| 526 | *session_path = live_path(name); |
| 527 | if (session_name) { |
| 528 | *session_name = name; |
| 529 | goto end; |
| 530 | } |
| 531 | |
| 532 | end_free: |
| 533 | free(name); |
| 534 | end: |
| 535 | return ret; |
| 536 | } |