| 1 | /* lttctl |
| 2 | * |
| 3 | * Linux Trace Toolkit Control |
| 4 | * |
| 5 | * Small program that controls LTT through libltt. |
| 6 | * |
| 7 | * Copyright 2005 - |
| 8 | * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
| 9 | */ |
| 10 | |
| 11 | #ifdef HAVE_CONFIG_H |
| 12 | #include <config.h> |
| 13 | #endif |
| 14 | |
| 15 | #include <liblttctl/lttctl.h> |
| 16 | #include <errno.h> |
| 17 | #include <stdio.h> |
| 18 | #include <stdlib.h> |
| 19 | #include <sys/types.h> |
| 20 | #include <sys/wait.h> |
| 21 | #include <unistd.h> |
| 22 | #include <signal.h> |
| 23 | #include <dirent.h> |
| 24 | #include <string.h> |
| 25 | #include <sys/stat.h> |
| 26 | |
| 27 | /* Buffer for file copy : 4k seems optimal. */ |
| 28 | #define BUF_SIZE 4096 |
| 29 | |
| 30 | enum trace_ctl_op { |
| 31 | CTL_OP_CREATE_START, |
| 32 | CTL_OP_CREATE, |
| 33 | CTL_OP_DESTROY, |
| 34 | CTL_OP_STOP_DESTROY, |
| 35 | CTL_OP_START, |
| 36 | CTL_OP_STOP, |
| 37 | CTL_OP_DAEMON, |
| 38 | CTL_OP_DESCRIPTION, |
| 39 | CTL_OP_NONE |
| 40 | }; |
| 41 | |
| 42 | static char *trace_name = NULL; |
| 43 | static char *mode_name = NULL; |
| 44 | static unsigned subbuf_size = 0; |
| 45 | static unsigned n_subbufs = 0; |
| 46 | static unsigned append_trace = 0; |
| 47 | static enum trace_mode mode = LTT_TRACE_NORMAL; |
| 48 | static enum trace_ctl_op op = CTL_OP_NONE; |
| 49 | static char *channel_root = NULL; |
| 50 | static char *trace_root = NULL; |
| 51 | static char *num_threads = "1"; |
| 52 | |
| 53 | static int sigchld_received = 0; |
| 54 | |
| 55 | void sigchld_handler(int signo) |
| 56 | { |
| 57 | printf("signal %d received\n", signo); |
| 58 | sigchld_received = 1; |
| 59 | } |
| 60 | |
| 61 | |
| 62 | /* Args : |
| 63 | * |
| 64 | */ |
| 65 | void show_arguments(void) |
| 66 | { |
| 67 | printf("Please use the following arguments :\n"); |
| 68 | printf("\n"); |
| 69 | printf("-n name Name of the trace.\n"); |
| 70 | printf("-b Create trace channels and start tracing (no daemon).\n"); |
| 71 | printf("-c Create trace channels.\n"); |
| 72 | printf("-m mode Normal or flight recorder mode.\n"); |
| 73 | printf(" Mode values : normal (default) or flight.\n"); |
| 74 | printf("-r Destroy trace channels.\n"); |
| 75 | printf("-R Stop tracing and destroy trace channels.\n"); |
| 76 | printf("-s Start tracing.\n"); |
| 77 | //printf(" Note : will automatically create a normal trace if " |
| 78 | // "none exists.\n"); |
| 79 | printf("-q Stop tracing.\n"); |
| 80 | printf("-d Create trace, spawn a lttd daemon, start tracing.\n"); |
| 81 | printf(" (optionnaly, you can set LTT_DAEMON\n"); |
| 82 | printf(" and the LTT_FACILITIES env. vars.)\n"); |
| 83 | printf("-t Trace root path. (ex. /root/traces/example_trace)\n"); |
| 84 | printf("-l LTT channels root path. (ex. /mnt/relayfs/ltt)\n"); |
| 85 | printf("-z Size of the subbuffers (will be rounded to next page size)\n"); |
| 86 | printf("-x Number of subbuffers\n"); |
| 87 | printf("-e Get XML facilities description\n"); |
| 88 | printf("-a Append to trace\n"); |
| 89 | printf("-N Number of lttd threads\n"); |
| 90 | printf("\n"); |
| 91 | } |
| 92 | |
| 93 | |
| 94 | /* parse_arguments |
| 95 | * |
| 96 | * Parses the command line arguments. |
| 97 | * |
| 98 | * Returns -1 if the arguments were correct, but doesn't ask for program |
| 99 | * continuation. Returns EINVAL if the arguments are incorrect, or 0 if OK. |
| 100 | */ |
| 101 | int parse_arguments(int argc, char **argv) |
| 102 | { |
| 103 | int ret = 0; |
| 104 | int argn = 1; |
| 105 | |
| 106 | if(argc == 2) { |
| 107 | if(strcmp(argv[1], "-h") == 0) { |
| 108 | return -1; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | while(argn < argc) { |
| 113 | |
| 114 | switch(argv[argn][0]) { |
| 115 | case '-': |
| 116 | switch(argv[argn][1]) { |
| 117 | case 'n': |
| 118 | if(argn+1 < argc) { |
| 119 | trace_name = argv[argn+1]; |
| 120 | argn++; |
| 121 | } else { |
| 122 | printf("Specify a trace name after -n.\n"); |
| 123 | printf("\n"); |
| 124 | ret = EINVAL; |
| 125 | } |
| 126 | |
| 127 | break; |
| 128 | case 'b': |
| 129 | op = CTL_OP_CREATE_START; |
| 130 | break; |
| 131 | case 'c': |
| 132 | op = CTL_OP_CREATE; |
| 133 | break; |
| 134 | case 'm': |
| 135 | if(argn+1 < argc) { |
| 136 | mode_name = argv[argn+1]; |
| 137 | argn++; |
| 138 | if(strcmp(mode_name, "normal") == 0) |
| 139 | mode = LTT_TRACE_NORMAL; |
| 140 | else if(strcmp(mode_name, "flight") == 0) |
| 141 | mode = LTT_TRACE_FLIGHT; |
| 142 | else { |
| 143 | printf("Invalid mode '%s'.\n", argv[argn]); |
| 144 | printf("\n"); |
| 145 | ret = EINVAL; |
| 146 | } |
| 147 | } else { |
| 148 | printf("Specify a mode after -m.\n"); |
| 149 | printf("\n"); |
| 150 | ret = EINVAL; |
| 151 | } |
| 152 | break; |
| 153 | case 'r': |
| 154 | op = CTL_OP_DESTROY; |
| 155 | break; |
| 156 | case 'R': |
| 157 | op = CTL_OP_STOP_DESTROY; |
| 158 | break; |
| 159 | case 's': |
| 160 | op = CTL_OP_START; |
| 161 | break; |
| 162 | case 'q': |
| 163 | op = CTL_OP_STOP; |
| 164 | break; |
| 165 | case 'z': |
| 166 | if(argn+1 < argc) { |
| 167 | subbuf_size = (unsigned)atoi(argv[argn+1]); |
| 168 | argn++; |
| 169 | } else { |
| 170 | printf("Specify a number of subbuffers after -z.\n"); |
| 171 | printf("\n"); |
| 172 | ret = EINVAL; |
| 173 | } |
| 174 | break; |
| 175 | case 'x': |
| 176 | if(argn+1 < argc) { |
| 177 | n_subbufs = (unsigned)atoi(argv[argn+1]); |
| 178 | argn++; |
| 179 | } else { |
| 180 | printf("Specify a subbuffer size after -x.\n"); |
| 181 | printf("\n"); |
| 182 | ret = EINVAL; |
| 183 | } |
| 184 | break; |
| 185 | case 'd': |
| 186 | op = CTL_OP_DAEMON; |
| 187 | break; |
| 188 | case 'e': |
| 189 | op = CTL_OP_DESCRIPTION; |
| 190 | break; |
| 191 | case 't': |
| 192 | if(argn+1 < argc) { |
| 193 | trace_root = argv[argn+1]; |
| 194 | argn++; |
| 195 | } else { |
| 196 | printf("Specify a trace root path after -t.\n"); |
| 197 | printf("\n"); |
| 198 | ret = EINVAL; |
| 199 | } |
| 200 | break; |
| 201 | case 'l': |
| 202 | if(argn+1 < argc) { |
| 203 | channel_root = argv[argn+1]; |
| 204 | argn++; |
| 205 | } else { |
| 206 | printf("Specify a channel root path after -l.\n"); |
| 207 | printf("\n"); |
| 208 | ret = EINVAL; |
| 209 | } |
| 210 | break; |
| 211 | case 'a': |
| 212 | append_trace = 1; |
| 213 | break; |
| 214 | case 'N': |
| 215 | if(argn+1 < argc) { |
| 216 | num_threads = argv[argn+1]; |
| 217 | argn++; |
| 218 | } |
| 219 | break; |
| 220 | default: |
| 221 | printf("Invalid argument '%s'.\n", argv[argn]); |
| 222 | printf("\n"); |
| 223 | ret = EINVAL; |
| 224 | } |
| 225 | break; |
| 226 | default: |
| 227 | printf("Invalid argument '%s'.\n", argv[argn]); |
| 228 | printf("\n"); |
| 229 | ret = EINVAL; |
| 230 | } |
| 231 | argn++; |
| 232 | } |
| 233 | |
| 234 | if(op != CTL_OP_DESCRIPTION && trace_name == NULL) { |
| 235 | printf("Please specify a trace name.\n"); |
| 236 | printf("\n"); |
| 237 | ret = EINVAL; |
| 238 | } |
| 239 | |
| 240 | if(op == CTL_OP_NONE) { |
| 241 | printf("Please specify an operation.\n"); |
| 242 | printf("\n"); |
| 243 | ret = EINVAL; |
| 244 | } |
| 245 | |
| 246 | if(op == CTL_OP_DAEMON) { |
| 247 | if(trace_root == NULL) { |
| 248 | printf("Please specify -t trace_root_path with the -d option.\n"); |
| 249 | printf("\n"); |
| 250 | ret = EINVAL; |
| 251 | } |
| 252 | if(channel_root == NULL) { |
| 253 | printf("Please specify -l ltt_root_path with the -d option.\n"); |
| 254 | printf("\n"); |
| 255 | ret = EINVAL; |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | if(op == CTL_OP_DESCRIPTION) { |
| 260 | if(trace_root == NULL) { |
| 261 | printf("Please specify -t trace_root_path with the -e option.\n"); |
| 262 | printf("\n"); |
| 263 | ret = EINVAL; |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | return ret; |
| 268 | } |
| 269 | |
| 270 | void show_info(void) |
| 271 | { |
| 272 | printf("Linux Trace Toolkit Trace Control\n"); |
| 273 | printf("\n"); |
| 274 | if(trace_name != NULL) { |
| 275 | printf("Controlling trace : %s\n", trace_name); |
| 276 | printf("\n"); |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | int create_eventdefs(void) |
| 281 | { |
| 282 | int ret = 0; |
| 283 | char eventdefs_path[PATH_MAX]; |
| 284 | char eventdefs_file[PATH_MAX]; |
| 285 | char facilities_file[PATH_MAX]; |
| 286 | char read_buf[BUF_SIZE]; |
| 287 | struct dirent *entry; |
| 288 | char *facilities_path = getenv("LTT_FACILITIES"); |
| 289 | if(facilities_path == NULL) facilities_path = |
| 290 | PACKAGE_DATA_DIR "/" PACKAGE "/facilities"; |
| 291 | |
| 292 | ret = mkdir(trace_root, S_IRWXU|S_IRWXG|S_IRWXO); |
| 293 | if(ret == -1 && errno != EEXIST) { |
| 294 | ret = errno; |
| 295 | perror("Cannot create trace_root directory"); |
| 296 | printf("trace_root is %s\n", trace_root); |
| 297 | goto error; |
| 298 | } |
| 299 | ret = 0; |
| 300 | |
| 301 | size_t trace_root_len = strlen(trace_root); |
| 302 | strncpy(eventdefs_path, trace_root, PATH_MAX); |
| 303 | strncat(eventdefs_path, "/eventdefs/", PATH_MAX - trace_root_len); |
| 304 | size_t eventdefs_path_len = strlen(eventdefs_path); |
| 305 | ret = mkdir(eventdefs_path, S_IRWXU|S_IRWXG|S_IRWXO); |
| 306 | if(ret == -1 && (!append_trace || errno != EEXIST)) { |
| 307 | ret = errno; |
| 308 | perror("Cannot create eventdefs directory"); |
| 309 | goto error; |
| 310 | } |
| 311 | ret = 0; |
| 312 | |
| 313 | DIR *facilities_dir = opendir(facilities_path); |
| 314 | |
| 315 | if(facilities_dir == NULL) { |
| 316 | perror("Cannot open facilities directory"); |
| 317 | ret = EEXIST; |
| 318 | goto error; |
| 319 | } |
| 320 | |
| 321 | while((entry = readdir(facilities_dir)) != NULL) { |
| 322 | if(entry->d_name[0] == '.') continue; |
| 323 | |
| 324 | printf("Appending facility file %s\n", entry->d_name); |
| 325 | strncpy(eventdefs_file, eventdefs_path, PATH_MAX); |
| 326 | strncat(eventdefs_file, entry->d_name, PATH_MAX - eventdefs_path_len); |
| 327 | /* Append to the file */ |
| 328 | FILE *dest = fopen(eventdefs_file, "a"); |
| 329 | if(!dest) { |
| 330 | perror("Cannot create eventdefs file"); |
| 331 | continue; |
| 332 | } |
| 333 | strncpy(facilities_file, facilities_path, PATH_MAX); |
| 334 | size_t facilities_dir_len = strlen(facilities_path); |
| 335 | strncat(facilities_file, "/", PATH_MAX - facilities_dir_len); |
| 336 | strncat(facilities_file, entry->d_name, PATH_MAX - facilities_dir_len-1); |
| 337 | FILE *src = fopen(facilities_file, "r"); |
| 338 | if(!src) { |
| 339 | ret = errno; |
| 340 | perror("Cannot open eventdefs file for reading"); |
| 341 | goto close_dest; |
| 342 | } |
| 343 | |
| 344 | do { |
| 345 | size_t read_size, write_size; |
| 346 | read_size = fread(read_buf, sizeof(char), BUF_SIZE, src); |
| 347 | if(ferror(src)) { |
| 348 | ret = errno; |
| 349 | perror("Cannot read eventdefs file"); |
| 350 | goto close_src; |
| 351 | } |
| 352 | write_size = fwrite(read_buf, sizeof(char), read_size, dest); |
| 353 | if(ferror(dest)) { |
| 354 | ret = errno; |
| 355 | perror("Cannot write eventdefs file"); |
| 356 | goto close_src; |
| 357 | } |
| 358 | } while(!feof(src)); |
| 359 | |
| 360 | /* Add spacing between facilities */ |
| 361 | fwrite("\n", 1, 1, dest); |
| 362 | |
| 363 | close_src: |
| 364 | fclose(src); |
| 365 | close_dest: |
| 366 | fclose(dest); |
| 367 | } |
| 368 | |
| 369 | closedir(facilities_dir); |
| 370 | |
| 371 | error: |
| 372 | return ret; |
| 373 | |
| 374 | } |
| 375 | |
| 376 | |
| 377 | int lttctl_daemon(struct lttctl_handle *handle, char *trace_name) |
| 378 | { |
| 379 | char channel_path[PATH_MAX] = ""; |
| 380 | pid_t pid; |
| 381 | int ret; |
| 382 | char *lttd_path = getenv("LTT_DAEMON"); |
| 383 | struct sigaction act; |
| 384 | |
| 385 | if(lttd_path == NULL) lttd_path = |
| 386 | PACKAGE_BIN_DIR "/lttd"; |
| 387 | |
| 388 | strcat(channel_path, channel_root); |
| 389 | strcat(channel_path, "/"); |
| 390 | strcat(channel_path, trace_name); |
| 391 | |
| 392 | |
| 393 | ret = lttctl_create_trace(handle, trace_name, mode, subbuf_size, n_subbufs); |
| 394 | if(ret != 0) goto create_error; |
| 395 | |
| 396 | act.sa_handler = sigchld_handler; |
| 397 | sigemptyset(&(act.sa_mask)); |
| 398 | sigaddset(&(act.sa_mask), SIGCHLD); |
| 399 | sigaction(SIGCHLD, &act, NULL); |
| 400 | |
| 401 | pid = fork(); |
| 402 | |
| 403 | if(pid > 0) { |
| 404 | int status; |
| 405 | /* parent */ |
| 406 | while(!(sigchld_received)) pause(); |
| 407 | |
| 408 | waitpid(pid, &status, 0); |
| 409 | ret = 0; |
| 410 | if(WIFEXITED(status)) |
| 411 | ret = WEXITSTATUS(status); |
| 412 | if(ret) goto start_error; |
| 413 | |
| 414 | printf("Creating supplementary trace files\n"); |
| 415 | ret = create_eventdefs(); |
| 416 | if(ret) goto start_error; |
| 417 | |
| 418 | } else if(pid == 0) { |
| 419 | /* child */ |
| 420 | int ret; |
| 421 | if(append_trace) |
| 422 | ret = execlp(lttd_path, lttd_path, "-t", trace_root, "-c", |
| 423 | channel_path, "-d", "-a", "-N", num_threads, NULL); |
| 424 | else |
| 425 | ret = execlp(lttd_path, lttd_path, "-t", trace_root, "-c", |
| 426 | channel_path, "-d", "-N", num_threads, NULL); |
| 427 | if(ret) { |
| 428 | ret = errno; |
| 429 | perror("Error in executing the lttd daemon"); |
| 430 | exit(ret); |
| 431 | } |
| 432 | } else { |
| 433 | /* error */ |
| 434 | perror("Error in forking for lttd daemon"); |
| 435 | } |
| 436 | |
| 437 | ret = lttctl_start(handle, trace_name); |
| 438 | if(ret != 0) goto start_error; |
| 439 | |
| 440 | return 0; |
| 441 | |
| 442 | /* error handling */ |
| 443 | start_error: |
| 444 | printf("Trace start error\n"); |
| 445 | ret |= lttctl_destroy_trace(handle, trace_name); |
| 446 | create_error: |
| 447 | return ret; |
| 448 | } |
| 449 | |
| 450 | int main(int argc, char ** argv) |
| 451 | { |
| 452 | int ret; |
| 453 | struct lttctl_handle *handle; |
| 454 | |
| 455 | ret = parse_arguments(argc, argv); |
| 456 | |
| 457 | if(ret != 0) show_arguments(); |
| 458 | if(ret == EINVAL) return EINVAL; |
| 459 | if(ret == -1) return 0; |
| 460 | |
| 461 | show_info(); |
| 462 | |
| 463 | handle = lttctl_create_handle(); |
| 464 | |
| 465 | if(handle == NULL) return -1; |
| 466 | |
| 467 | switch(op) { |
| 468 | case CTL_OP_CREATE_START: |
| 469 | ret = lttctl_create_trace(handle, trace_name, mode, subbuf_size, |
| 470 | n_subbufs); |
| 471 | if(!ret) |
| 472 | ret = lttctl_start(handle, trace_name); |
| 473 | break; |
| 474 | case CTL_OP_CREATE: |
| 475 | ret = lttctl_create_trace(handle, trace_name, mode, subbuf_size, |
| 476 | n_subbufs); |
| 477 | break; |
| 478 | case CTL_OP_DESTROY: |
| 479 | ret = lttctl_destroy_trace(handle, trace_name); |
| 480 | break; |
| 481 | case CTL_OP_STOP_DESTROY: |
| 482 | ret = lttctl_stop(handle, trace_name); |
| 483 | if(!ret) |
| 484 | ret = lttctl_destroy_trace(handle, trace_name); |
| 485 | break; |
| 486 | case CTL_OP_START: |
| 487 | ret = lttctl_start(handle, trace_name); |
| 488 | break; |
| 489 | case CTL_OP_STOP: |
| 490 | ret = lttctl_stop(handle, trace_name); |
| 491 | break; |
| 492 | case CTL_OP_DAEMON: |
| 493 | ret = lttctl_daemon(handle, trace_name); |
| 494 | break; |
| 495 | case CTL_OP_DESCRIPTION: |
| 496 | ret = create_eventdefs(); |
| 497 | break; |
| 498 | case CTL_OP_NONE: |
| 499 | break; |
| 500 | } |
| 501 | |
| 502 | ret |= lttctl_destroy_handle(handle); |
| 503 | |
| 504 | return ret; |
| 505 | } |