lttng-consumerd/lttng-consumerd.c

   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 #include <urcu/compiler.h>
  42
  43 #include <lttng-consumerd.h>
  44 #include <lttng-kernel-ctl.h>
  45 #include <lttng-sessiond-comm.h>
  46 #include <lttng/lttng-kconsumer.h>
  47 #include <lttng/lttng-ustconsumer.h>
  48 #include <lttngerr.h>
  49
  50 /* TODO : support UST (all direct kernctl accesses). */
  51
  52 /* the two threads (receive fd and poll) */
  53 static pthread_t threads[2];
  54
  55 /* to count the number of time the user pressed ctrl+c */
  56 static int sigintcount = 0;
  57
  58 /* Argument variables */
  59 int opt_quiet;
  60 int opt_verbose;
  61 static int opt_daemon;
  62 static const char *progname;
  63 static char command_sock_path[PATH_MAX]; /* Global command socket path */
  64 static char error_sock_path[PATH_MAX]; /* Global error path */
  65 static enum lttng_consumer_type opt_type = LTTNG_CONSUMER_KERNEL;
  66
  67 /* the liblttngconsumerd context */
  68 static struct lttng_consumer_local_data *ctx;
  69
  70 /*
  71  * Signal handler for the daemon
  72  */
  73 static void sighandler(int sig)
  74 {
  75         if (sig == SIGINT && sigintcount++ == 0) {
  76                 DBG("ignoring first SIGINT");
  77                 return;
  78         }
  79
  80         lttng_consumer_should_exit(ctx);
  81 }
  82
  83 /*
  84  * Setup signal handler for :
  85  *      SIGINT, SIGTERM, SIGPIPE
  86  */
  87 static int set_signal_handler(void)
  88 {
  89         int ret = 0;
  90         struct sigaction sa;
  91         sigset_t sigset;
  92
  93         if ((ret = sigemptyset(&sigset)) < 0) {
  94                 perror("sigemptyset");
  95                 return ret;
  96         }
  97
  98         sa.sa_handler = sighandler;
  99         sa.sa_mask = sigset;
 100         sa.sa_flags = 0;
 101         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 102                 perror("sigaction");
 103                 return ret;
 104         }
 105
 106         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 107                 perror("sigaction");
 108                 return ret;
 109         }
 110
 111         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 112                 perror("sigaction");
 113                 return ret;
 114         }
 115
 116         return ret;
 117 }
 118
 119 /*
 120  * usage function on stderr
 121  */
 122 static void usage(void)
 123 {
 124         fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 125         fprintf(stderr, "  -h, --help                         "
 126                         "Display this usage.\n");
 127         fprintf(stderr, "  -c, --consumerd-cmd-sock PATH     "
 128                         "Specify path for the command socket\n");
 129         fprintf(stderr, "  -e, --consumerd-err-sock PATH     "
 130                         "Specify path for the error socket\n");
 131         fprintf(stderr, "  -d, --daemonize                    "
 132                         "Start as a daemon.\n");
 133         fprintf(stderr, "  -q, --quiet                        "
 134                         "No output at all.\n");
 135         fprintf(stderr, "  -v, --verbose                      "
 136                         "Verbose mode. Activate DBG() macro.\n");
 137         fprintf(stderr, "  -V, --version                      "
 138                         "Show version number.\n");
 139         fprintf(stderr, "  -k, --kernel                       "
 140                         "Consumer kernel buffers (default).\n");
 141         fprintf(stderr, "  -u, --ust                          "
 142                         "Consumer UST buffers.%s\n",
 143 #ifdef HAVE_LIBLTTNG_UST_CTL
 144                         ""
 145 #else
 146                         " (support not compiled in)"
 147 #endif
 148                         );
 149 }
 150
 151 /*
 152  * daemon argument parsing
 153  */
 154 static void parse_args(int argc, char **argv)
 155 {
 156         int c;
 157
 158         static struct option long_options[] = {
 159                 { "consumerd-cmd-sock", 1, 0, 'c' },
 160                 { "consumerd-err-sock", 1, 0, 'e' },
 161                 { "daemonize", 0, 0, 'd' },
 162                 { "help", 0, 0, 'h' },
 163                 { "quiet", 0, 0, 'q' },
 164                 { "verbose", 0, 0, 'v' },
 165                 { "version", 0, 0, 'V' },
 166                 { "kernel", 0, 0, 'k' },
 167 #ifdef HAVE_LIBLTTNG_UST_CTL
 168                 { "ust", 0, 0, 'u' },
 169 #endif
 170                 { NULL, 0, 0, 0 }
 171         };
 172
 173         while (1) {
 174                 int option_index = 0;
 175                 c = getopt_long(argc, argv, "dhqvVku" "c:e:", long_options, &option_index);
 176                 if (c == -1) {
 177                         break;
 178                 }
 179
 180                 switch (c) {
 181                 case 0:
 182                         fprintf(stderr, "option %s", long_options[option_index].name);
 183                         if (optarg) {
 184                                 fprintf(stderr, " with arg %s\n", optarg);
 185                         }
 186                         break;
 187                 case 'c':
 188                         snprintf(command_sock_path, PATH_MAX, "%s", optarg);
 189                         break;
 190                 case 'e':
 191                         snprintf(error_sock_path, PATH_MAX, "%s", optarg);
 192                         break;
 193                 case 'd':
 194                         opt_daemon = 1;
 195                         break;
 196                 case 'h':
 197                         usage();
 198                         exit(EXIT_FAILURE);
 199                 case 'q':
 200                         opt_quiet = 1;
 201                         break;
 202                 case 'v':
 203                         opt_verbose = 1;
 204                         break;
 205                 case 'V':
 206                         fprintf(stdout, "%s\n", VERSION);
 207                         exit(EXIT_SUCCESS);
 208                 case 'k':
 209                         opt_type = LTTNG_CONSUMER_KERNEL;
 210                         break;
 211 #ifdef HAVE_LIBLTTNG_UST_CTL
 212                 case 'u':
 213 # if (CAA_BITS_PER_LONG == 64)
 214                         opt_type = LTTNG_CONSUMER64_UST;
 215 # elif (CAA_BITS_PER_LONG == 32)
 216                         opt_type = LTTNG_CONSUMER32_UST;
 217 # else
 218 #  error "Unknown bitness"
 219 # endif
 220                         break;
 221 #endif
 222                 default:
 223                         usage();
 224                         exit(EXIT_FAILURE);
 225                 }
 226         }
 227 }
 228
 229 /*
 230  * main
 231  */
 232 int main(int argc, char **argv)
 233 {
 234         int i;
 235         int ret = 0;
 236         void *status;
 237
 238         /* Parse arguments */
 239         progname = argv[0];
 240         parse_args(argc, argv);
 241
 242         /* Daemonize */
 243         if (opt_daemon) {
 244                 ret = daemon(0, 0);
 245                 if (ret < 0) {
 246                         perror("daemon");
 247                         goto error;
 248                 }
 249         }
 250
 251         if (strlen(command_sock_path) == 0) {
 252                 switch (opt_type) {
 253                 case LTTNG_CONSUMER_KERNEL:
 254                         snprintf(command_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH,
 255                                         LTTNG_RUNDIR);
 256                         break;
 257                 case LTTNG_CONSUMER64_UST:
 258                         snprintf(command_sock_path, PATH_MAX,
 259                                         USTCONSUMERD64_CMD_SOCK_PATH, LTTNG_RUNDIR);
 260                         break;
 261                 case LTTNG_CONSUMER32_UST:
 262                         snprintf(command_sock_path, PATH_MAX,
 263                                         USTCONSUMERD32_CMD_SOCK_PATH, LTTNG_RUNDIR);
 264                         break;
 265                 default:
 266                         WARN("Unknown consumerd type");
 267                         goto error;
 268                 }
 269         }
 270
 271         /* Init */
 272         lttng_consumer_init();
 273
 274         /* create the consumer instance with and assign the callbacks */
 275         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 276                 NULL, lttng_consumer_on_recv_stream, NULL);
 277         if (ctx == NULL) {
 278                 goto error;
 279         }
 280
 281         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 282         if (strlen(error_sock_path) == 0) {
 283                 switch (opt_type) {
 284                 case LTTNG_CONSUMER_KERNEL:
 285                         snprintf(error_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH,
 286                                         LTTNG_RUNDIR);
 287                         break;
 288                 case LTTNG_CONSUMER64_UST:
 289                         snprintf(error_sock_path, PATH_MAX,
 290                                         USTCONSUMERD64_ERR_SOCK_PATH, LTTNG_RUNDIR);
 291                         break;
 292                 case LTTNG_CONSUMER32_UST:
 293                         snprintf(error_sock_path, PATH_MAX,
 294                                         USTCONSUMERD32_ERR_SOCK_PATH, LTTNG_RUNDIR);
 295                         break;
 296                 default:
 297                         WARN("Unknown consumerd type");
 298                         goto error;
 299                 }
 300         }
 301
 302         if (set_signal_handler() < 0) {
 303                 goto error;
 304         }
 305
 306         /* Connect to the socket created by lttng-sessiond to report errors */
 307         DBG("Connecting to error socket %s", error_sock_path);
 308         ret = lttcomm_connect_unix_sock(error_sock_path);
 309         /* not a fatal error, but all communication with lttng-sessiond will fail */
 310         if (ret < 0) {
 311                 WARN("Cannot connect to error socket, is lttng-sessiond started ?");
 312         }
 313         lttng_consumer_set_error_sock(ctx, ret);
 314
 315         /* Create the thread to manage the receive of fd */
 316         ret = pthread_create(&threads[0], NULL, lttng_consumer_thread_receive_fds,
 317                         (void *) ctx);
 318         if (ret != 0) {
 319                 perror("pthread_create");
 320                 goto error;
 321         }
 322
 323         /* Create thread to manage the polling/writing of traces */
 324         ret = pthread_create(&threads[1], NULL, lttng_consumer_thread_poll_fds,
 325                         (void *) ctx);
 326         if (ret != 0) {
 327                 perror("pthread_create");
 328                 goto error;
 329         }
 330
 331         for (i = 0; i < 2; i++) {
 332                 ret = pthread_join(threads[i], &status);
 333                 if (ret != 0) {
 334                         perror("pthread_join");
 335                         goto error;
 336                 }
 337         }
 338         ret = EXIT_SUCCESS;
 339         lttng_consumer_send_error(ctx, CONSUMERD_EXIT_SUCCESS);
 340         goto end;
 341
 342 error:
 343         ret = EXIT_FAILURE;
 344         lttng_consumer_send_error(ctx, CONSUMERD_EXIT_FAILURE);
 345
 346 end:
 347         lttng_consumer_destroy(ctx);
 348         lttng_consumer_cleanup();
 349
 350         return ret;
 351 }