| 1 | /* |
| 2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> |
| 3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of the GNU General Public License |
| 7 | * as published by the Free Software Foundation; only version 2 |
| 8 | * of the License. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 18 | */ |
| 19 | |
| 20 | #define _GNU_SOURCE |
| 21 | #include <fcntl.h> |
| 22 | #include <getopt.h> |
| 23 | #include <grp.h> |
| 24 | #include <limits.h> |
| 25 | #include <pthread.h> |
| 26 | #include <signal.h> |
| 27 | #include <stdio.h> |
| 28 | #include <stdlib.h> |
| 29 | #include <string.h> |
| 30 | #include <sys/ipc.h> |
| 31 | #include <sys/shm.h> |
| 32 | #include <sys/socket.h> |
| 33 | #include <sys/stat.h> |
| 34 | #include <sys/types.h> |
| 35 | #include <urcu/list.h> |
| 36 | #include <poll.h> |
| 37 | #include <unistd.h> |
| 38 | #include <sys/mman.h> |
| 39 | #include <assert.h> |
| 40 | #include <config.h> |
| 41 | |
| 42 | #include <lttng-consumerd.h> |
| 43 | #include <lttng-kernel-ctl.h> |
| 44 | #include <lttng-sessiond-comm.h> |
| 45 | #include <lttng/lttng-kconsumer.h> |
| 46 | #include <lttng/lttng-ustconsumer.h> |
| 47 | #include <lttngerr.h> |
| 48 | |
| 49 | /* TODO : support UST (all direct kernctl accesses). */ |
| 50 | |
| 51 | /* the two threads (receive fd and poll) */ |
| 52 | static pthread_t threads[2]; |
| 53 | |
| 54 | /* to count the number of time the user pressed ctrl+c */ |
| 55 | static int sigintcount = 0; |
| 56 | |
| 57 | /* Argument variables */ |
| 58 | int opt_quiet; |
| 59 | int opt_verbose; |
| 60 | static int opt_daemon; |
| 61 | static const char *progname; |
| 62 | static char command_sock_path[PATH_MAX]; /* Global command socket path */ |
| 63 | static char error_sock_path[PATH_MAX]; /* Global error path */ |
| 64 | static enum lttng_consumer_type opt_type = LTTNG_CONSUMER_KERNEL; |
| 65 | |
| 66 | /* the liblttngkconsumerd context */ |
| 67 | static struct lttng_consumer_local_data *ctx; |
| 68 | |
| 69 | /* |
| 70 | * Signal handler for the daemon |
| 71 | */ |
| 72 | static void sighandler(int sig) |
| 73 | { |
| 74 | if (sig == SIGINT && sigintcount++ == 0) { |
| 75 | DBG("ignoring first SIGINT"); |
| 76 | return; |
| 77 | } |
| 78 | |
| 79 | lttng_consumer_should_exit(ctx); |
| 80 | } |
| 81 | |
| 82 | /* |
| 83 | * Setup signal handler for : |
| 84 | * SIGINT, SIGTERM, SIGPIPE |
| 85 | */ |
| 86 | static int set_signal_handler(void) |
| 87 | { |
| 88 | int ret = 0; |
| 89 | struct sigaction sa; |
| 90 | sigset_t sigset; |
| 91 | |
| 92 | if ((ret = sigemptyset(&sigset)) < 0) { |
| 93 | perror("sigemptyset"); |
| 94 | return ret; |
| 95 | } |
| 96 | |
| 97 | sa.sa_handler = sighandler; |
| 98 | sa.sa_mask = sigset; |
| 99 | sa.sa_flags = 0; |
| 100 | if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { |
| 101 | perror("sigaction"); |
| 102 | return ret; |
| 103 | } |
| 104 | |
| 105 | if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { |
| 106 | perror("sigaction"); |
| 107 | return ret; |
| 108 | } |
| 109 | |
| 110 | if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) { |
| 111 | perror("sigaction"); |
| 112 | return ret; |
| 113 | } |
| 114 | |
| 115 | return ret; |
| 116 | } |
| 117 | |
| 118 | /* |
| 119 | * usage function on stderr |
| 120 | */ |
| 121 | static void usage(void) |
| 122 | { |
| 123 | fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname); |
| 124 | fprintf(stderr, " -h, --help " |
| 125 | "Display this usage.\n"); |
| 126 | fprintf(stderr, " -c, --kconsumerd-cmd-sock PATH " |
| 127 | "Specify path for the command socket\n"); |
| 128 | fprintf(stderr, " -e, --kconsumerd-err-sock PATH " |
| 129 | "Specify path for the error socket\n"); |
| 130 | fprintf(stderr, " -d, --daemonize " |
| 131 | "Start as a daemon.\n"); |
| 132 | fprintf(stderr, " -q, --quiet " |
| 133 | "No output at all.\n"); |
| 134 | fprintf(stderr, " -v, --verbose " |
| 135 | "Verbose mode. Activate DBG() macro.\n"); |
| 136 | fprintf(stderr, " -V, --version " |
| 137 | "Show version number.\n"); |
| 138 | fprintf(stderr, " -k, --kernel " |
| 139 | "Consumer kernel buffers (default).\n"); |
| 140 | fprintf(stderr, " -u, --ust " |
| 141 | "Consumer UST buffers.%s\n", |
| 142 | #ifdef CONFIG_LTTNG_TOOLS_HAVE_UST |
| 143 | "" |
| 144 | #else |
| 145 | " (support not compiled in)" |
| 146 | #endif |
| 147 | ); |
| 148 | } |
| 149 | |
| 150 | /* |
| 151 | * daemon argument parsing |
| 152 | */ |
| 153 | static void parse_args(int argc, char **argv) |
| 154 | { |
| 155 | int c; |
| 156 | |
| 157 | static struct option long_options[] = { |
| 158 | { "kconsumerd-cmd-sock", 1, 0, 'c' }, |
| 159 | { "kconsumerd-err-sock", 1, 0, 'e' }, |
| 160 | { "daemonize", 0, 0, 'd' }, |
| 161 | { "help", 0, 0, 'h' }, |
| 162 | { "quiet", 0, 0, 'q' }, |
| 163 | { "verbose", 0, 0, 'v' }, |
| 164 | { "version", 0, 0, 'V' }, |
| 165 | { "kernel", 0, 0, 'k' }, |
| 166 | #ifdef CONFIG_LTTNG_TOOLS_HAVE_UST |
| 167 | { "ust", 0, 0, 'u' }, |
| 168 | #endif |
| 169 | { NULL, 0, 0, 0 } |
| 170 | }; |
| 171 | |
| 172 | while (1) { |
| 173 | int option_index = 0; |
| 174 | c = getopt_long(argc, argv, "dhqvVku" "c:e:", long_options, &option_index); |
| 175 | if (c == -1) { |
| 176 | break; |
| 177 | } |
| 178 | |
| 179 | switch (c) { |
| 180 | case 0: |
| 181 | fprintf(stderr, "option %s", long_options[option_index].name); |
| 182 | if (optarg) { |
| 183 | fprintf(stderr, " with arg %s\n", optarg); |
| 184 | } |
| 185 | break; |
| 186 | case 'c': |
| 187 | snprintf(command_sock_path, PATH_MAX, "%s", optarg); |
| 188 | break; |
| 189 | case 'e': |
| 190 | snprintf(error_sock_path, PATH_MAX, "%s", optarg); |
| 191 | break; |
| 192 | case 'd': |
| 193 | opt_daemon = 1; |
| 194 | break; |
| 195 | case 'h': |
| 196 | usage(); |
| 197 | exit(EXIT_FAILURE); |
| 198 | case 'q': |
| 199 | opt_quiet = 1; |
| 200 | break; |
| 201 | case 'v': |
| 202 | opt_verbose = 1; |
| 203 | break; |
| 204 | case 'V': |
| 205 | fprintf(stdout, "%s\n", VERSION); |
| 206 | exit(EXIT_SUCCESS); |
| 207 | case 'k': |
| 208 | opt_type = LTTNG_CONSUMER_KERNEL; |
| 209 | break; |
| 210 | #ifdef CONFIG_LTTNG_TOOLS_HAVE_UST |
| 211 | case 'u': |
| 212 | opt_type = LTTNG_CONSUMER_UST; |
| 213 | break; |
| 214 | #endif |
| 215 | default: |
| 216 | usage(); |
| 217 | exit(EXIT_FAILURE); |
| 218 | } |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | /* |
| 223 | * Consume data on a file descriptor and write it on a trace file. |
| 224 | */ |
| 225 | static int read_subbuffer(struct lttng_consumer_stream *stream) |
| 226 | { |
| 227 | unsigned long len; |
| 228 | int err; |
| 229 | long ret = 0; |
| 230 | int infd = stream->wait_fd; |
| 231 | |
| 232 | DBG("In read_subbuffer (infd : %d)", infd); |
| 233 | /* Get the next subbuffer */ |
| 234 | err = kernctl_get_next_subbuf(infd); |
| 235 | if (err != 0) { |
| 236 | ret = errno; |
| 237 | /* |
| 238 | * This is a debug message even for single-threaded consumer, |
| 239 | * because poll() have more relaxed criterions than get subbuf, |
| 240 | * so get_subbuf may fail for short race windows where poll() |
| 241 | * would issue wakeups. |
| 242 | */ |
| 243 | DBG("Reserving sub buffer failed (everything is normal, " |
| 244 | "it is due to concurrency)"); |
| 245 | goto end; |
| 246 | } |
| 247 | |
| 248 | switch (stream->output) { |
| 249 | case LTTNG_EVENT_SPLICE: |
| 250 | /* read the whole subbuffer */ |
| 251 | err = kernctl_get_padded_subbuf_size(infd, &len); |
| 252 | if (err != 0) { |
| 253 | ret = errno; |
| 254 | perror("Getting sub-buffer len failed."); |
| 255 | goto end; |
| 256 | } |
| 257 | |
| 258 | /* splice the subbuffer to the tracefile */ |
| 259 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, len); |
| 260 | if (ret < 0) { |
| 261 | /* |
| 262 | * display the error but continue processing to try |
| 263 | * to release the subbuffer |
| 264 | */ |
| 265 | ERR("Error splicing to tracefile"); |
| 266 | } |
| 267 | break; |
| 268 | case LTTNG_EVENT_MMAP: |
| 269 | /* read the used subbuffer size */ |
| 270 | err = kernctl_get_padded_subbuf_size(infd, &len); |
| 271 | if (err != 0) { |
| 272 | ret = errno; |
| 273 | perror("Getting sub-buffer len failed."); |
| 274 | goto end; |
| 275 | } |
| 276 | /* write the subbuffer to the tracefile */ |
| 277 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); |
| 278 | if (ret < 0) { |
| 279 | /* |
| 280 | * display the error but continue processing to try |
| 281 | * to release the subbuffer |
| 282 | */ |
| 283 | ERR("Error writing to tracefile"); |
| 284 | } |
| 285 | break; |
| 286 | default: |
| 287 | ERR("Unknown output method"); |
| 288 | ret = -1; |
| 289 | } |
| 290 | |
| 291 | err = kernctl_put_next_subbuf(infd); |
| 292 | if (err != 0) { |
| 293 | ret = errno; |
| 294 | if (errno == EFAULT) { |
| 295 | perror("Error in unreserving sub buffer\n"); |
| 296 | } else if (errno == EIO) { |
| 297 | /* Should never happen with newer LTTng versions */ |
| 298 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); |
| 299 | } |
| 300 | goto end; |
| 301 | } |
| 302 | |
| 303 | end: |
| 304 | return ret; |
| 305 | } |
| 306 | |
| 307 | static int on_recv_stream(struct lttng_consumer_stream *stream) |
| 308 | { |
| 309 | int ret; |
| 310 | |
| 311 | /* Opening the tracefile in write mode */ |
| 312 | if (stream->path_name != NULL) { |
| 313 | ret = open(stream->path_name, |
| 314 | O_WRONLY|O_CREAT|O_TRUNC, S_IRWXU|S_IRWXG|S_IRWXO); |
| 315 | if (ret < 0) { |
| 316 | ERR("Opening %s", stream->path_name); |
| 317 | perror("open"); |
| 318 | goto error; |
| 319 | } |
| 320 | stream->out_fd = ret; |
| 321 | } |
| 322 | |
| 323 | if (stream->output == LTTNG_EVENT_MMAP) { |
| 324 | /* get the len of the mmap region */ |
| 325 | unsigned long mmap_len; |
| 326 | |
| 327 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); |
| 328 | if (ret != 0) { |
| 329 | ret = errno; |
| 330 | perror("kernctl_get_mmap_len"); |
| 331 | goto error_close_fd; |
| 332 | } |
| 333 | stream->mmap_len = (size_t) mmap_len; |
| 334 | |
| 335 | stream->mmap_base = mmap(NULL, stream->mmap_len, |
| 336 | PROT_READ, MAP_PRIVATE, stream->wait_fd, 0); |
| 337 | if (stream->mmap_base == MAP_FAILED) { |
| 338 | perror("Error mmaping"); |
| 339 | ret = -1; |
| 340 | goto error_close_fd; |
| 341 | } |
| 342 | } |
| 343 | |
| 344 | /* we return 0 to let the library handle the FD internally */ |
| 345 | return 0; |
| 346 | |
| 347 | error_close_fd: |
| 348 | { |
| 349 | int err; |
| 350 | |
| 351 | err = close(stream->out_fd); |
| 352 | assert(!err); |
| 353 | } |
| 354 | error: |
| 355 | return ret; |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * main |
| 360 | */ |
| 361 | int main(int argc, char **argv) |
| 362 | { |
| 363 | int i; |
| 364 | int ret = 0; |
| 365 | void *status; |
| 366 | |
| 367 | /* Parse arguments */ |
| 368 | progname = argv[0]; |
| 369 | parse_args(argc, argv); |
| 370 | |
| 371 | /* Daemonize */ |
| 372 | if (opt_daemon) { |
| 373 | ret = daemon(0, 0); |
| 374 | if (ret < 0) { |
| 375 | perror("daemon"); |
| 376 | goto error; |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | if (strlen(command_sock_path) == 0) { |
| 381 | snprintf(command_sock_path, PATH_MAX, |
| 382 | opt_type == LTTNG_CONSUMER_KERNEL ? |
| 383 | KCONSUMERD_CMD_SOCK_PATH : |
| 384 | USTCONSUMERD_CMD_SOCK_PATH); |
| 385 | } |
| 386 | /* create the consumer instance with and assign the callbacks */ |
| 387 | ctx = lttng_consumer_create(opt_type, read_subbuffer, NULL, on_recv_stream, NULL); |
| 388 | if (ctx == NULL) { |
| 389 | goto error; |
| 390 | } |
| 391 | |
| 392 | lttng_consumer_set_command_sock_path(ctx, command_sock_path); |
| 393 | if (strlen(error_sock_path) == 0) { |
| 394 | snprintf(error_sock_path, PATH_MAX, |
| 395 | opt_type == LTTNG_CONSUMER_KERNEL ? |
| 396 | KCONSUMERD_ERR_SOCK_PATH : |
| 397 | USTCONSUMERD_ERR_SOCK_PATH); |
| 398 | } |
| 399 | |
| 400 | if (set_signal_handler() < 0) { |
| 401 | goto error; |
| 402 | } |
| 403 | |
| 404 | /* Connect to the socket created by lttng-sessiond to report errors */ |
| 405 | DBG("Connecting to error socket %s", error_sock_path); |
| 406 | ret = lttcomm_connect_unix_sock(error_sock_path); |
| 407 | /* not a fatal error, but all communication with lttng-sessiond will fail */ |
| 408 | if (ret < 0) { |
| 409 | WARN("Cannot connect to error socket, is lttng-sessiond started ?"); |
| 410 | } |
| 411 | lttng_consumer_set_error_sock(ctx, ret); |
| 412 | |
| 413 | /* Create the thread to manage the receive of fd */ |
| 414 | ret = pthread_create(&threads[0], NULL, lttng_consumer_thread_receive_fds, |
| 415 | (void *) ctx); |
| 416 | if (ret != 0) { |
| 417 | perror("pthread_create"); |
| 418 | goto error; |
| 419 | } |
| 420 | |
| 421 | /* Create thread to manage the polling/writing of traces */ |
| 422 | ret = pthread_create(&threads[1], NULL, lttng_consumer_thread_poll_fds, |
| 423 | (void *) ctx); |
| 424 | if (ret != 0) { |
| 425 | perror("pthread_create"); |
| 426 | goto error; |
| 427 | } |
| 428 | |
| 429 | for (i = 0; i < 2; i++) { |
| 430 | ret = pthread_join(threads[i], &status); |
| 431 | if (ret != 0) { |
| 432 | perror("pthread_join"); |
| 433 | goto error; |
| 434 | } |
| 435 | } |
| 436 | ret = EXIT_SUCCESS; |
| 437 | lttng_consumer_send_error(ctx, CONSUMERD_EXIT_SUCCESS); |
| 438 | goto end; |
| 439 | |
| 440 | error: |
| 441 | ret = EXIT_FAILURE; |
| 442 | lttng_consumer_send_error(ctx, CONSUMERD_EXIT_FAILURE); |
| 443 | |
| 444 | end: |
| 445 | lttng_consumer_destroy(ctx); |
| 446 | lttng_consumer_cleanup(); |
| 447 | |
| 448 | return ret; |
| 449 | } |