libust/tracectl.c

   1 #define _GNU_SOURCE
   2 #include <stdio.h>
   3 #include <stdint.h>
   4 #include <signal.h>
   5 #include <sys/types.h>
   6 #include <sys/socket.h>
   7 #include <sys/un.h>
   8 #include <sched.h>
   9 #include <fcntl.h>
  10 #include <poll.h>
  11
  12 #include "marker.h"
  13 #include "tracer.h"
  14 #include "localerr.h"
  15 #include "ustcomm.h"
  16 #include "relay.h" /* FIXME: remove */
  17 #include "marker-control.h"
  18
  19 //#define USE_CLONE
  20
  21 #define USTSIGNAL SIGIO
  22
  23 #define MAX_MSG_SIZE (100)
  24 #define MSG_NOTIF 1
  25 #define MSG_REGISTER_NOTIF 2
  26
  27 char consumer_stack[10000];
  28
  29 struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
  30
  31 static struct ustcomm_app ustcomm_app;
  32
  33 struct tracecmd { /* no padding */
  34         uint32_t size;
  35         uint16_t command;
  36 };
  37
  38 //struct listener_arg {
  39 //      int pipe_fd;
  40 //};
  41
  42 struct trctl_msg {
  43         /* size: the size of all the fields except size itself */
  44         uint32_t size;
  45         uint16_t type;
  46         /* Only the necessary part of the payload is transferred. It
  47          * may even be none of it.
  48          */
  49         char payload[94];
  50 };
  51
  52 struct consumer_channel {
  53         int fd;
  54         struct ltt_channel_struct *chan;
  55 };
  56
  57 struct blocked_consumer {
  58         int fd_consumer;
  59         int fd_producer;
  60         int tmp_poll_idx;
  61
  62         /* args to ustcomm_send_reply */
  63         struct ustcomm_server server;
  64         struct ustcomm_source src;
  65
  66         /* args to ltt_do_get_subbuf */
  67         struct rchan_buf *rbuf;
  68         struct ltt_channel_buf_struct *lttbuf;
  69
  70         struct list_head list;
  71 };
  72
  73 static void print_markers(FILE *fp)
  74 {
  75         struct marker_iter iter;
  76
  77         lock_markers();
  78         marker_iter_reset(&iter);
  79         marker_iter_start(&iter);
  80
  81         while(iter.marker) {
  82                 fprintf(fp, "marker: %s_%s %d \"%s\"\n", iter.marker->channel, iter.marker->name, (int)imv_read(iter.marker->state), iter.marker->format);
  83                 marker_iter_next(&iter);
  84         }
  85         unlock_markers();
  86 }
  87
  88 void do_command(struct tracecmd *cmd)
  89 {
  90 }
  91
  92 void receive_commands()
  93 {
  94 }
  95
  96 int fd_notif = -1;
  97 void notif_cb(void)
  98 {
  99         int result;
 100         struct trctl_msg msg;
 101
 102         /* FIXME: fd_notif should probably be protected by a spinlock */
 103
 104         if(fd_notif == -1)
 105                 return;
 106
 107         msg.type = MSG_NOTIF;
 108         msg.size = sizeof(msg.type);
 109
 110         /* FIXME: don't block here */
 111         result = write(fd_notif, &msg, msg.size+sizeof(msg.size));
 112         if(result == -1) {
 113                 PERROR("write");
 114                 return;
 115         }
 116 }
 117
 118 static void inform_consumer_daemon(void)
 119 {
 120         ustcomm_request_consumer(getpid(), "metadata");
 121         ustcomm_request_consumer(getpid(), "ust");
 122 }
 123
 124 void process_blocked_consumers(void)
 125 {
 126         int n_fds = 0;
 127         struct pollfd *fds;
 128         struct blocked_consumer *bc;
 129         int idx = 0;
 130         char inbuf;
 131         int result;
 132
 133         list_for_each_entry(bc, &blocked_consumers, list) {
 134                 n_fds++;
 135         }
 136
 137         fds = (struct pollfd *) malloc(n_fds * sizeof(struct pollfd));
 138         if(fds == NULL) {
 139                 ERR("malloc returned NULL");
 140                 return;
 141         }
 142
 143         list_for_each_entry(bc, &blocked_consumers, list) {
 144                 fds[idx].fd = bc->fd_producer;
 145                 fds[idx].events = POLLIN;
 146                 bc->tmp_poll_idx = idx;
 147                 idx++;
 148         }
 149
 150         result = poll(fds, n_fds, 0);
 151         if(result == -1) {
 152                 PERROR("poll");
 153                 return;
 154         }
 155
 156         list_for_each_entry(bc, &blocked_consumers, list) {
 157                 if(fds[bc->tmp_poll_idx].revents) {
 158                         long consumed_old = 0;
 159                         char *reply;
 160
 161                         result = read(bc->fd_producer, &inbuf, 1);
 162                         if(result == -1) {
 163                                 PERROR("read");
 164                                 continue;
 165                         }
 166                         if(result == 0) {
 167                                 DBG("PRODUCER END");
 168
 169                                 close(bc->fd_producer);
 170
 171                                 list_del(&bc->list);
 172
 173                                 result = ustcomm_send_reply(&bc->server, "END", &bc->src);
 174                                 if(result < 0) {
 175                                         ERR("ustcomm_send_reply failed");
 176                                         continue;
 177                                 }
 178
 179                                 continue;
 180                         }
 181
 182                         result = ltt_do_get_subbuf(bc->rbuf, bc->lttbuf, &consumed_old);
 183                         if(result == -EAGAIN) {
 184                                 WARN("missed buffer?");
 185                                 continue;
 186                         }
 187                         else if(result < 0) {
 188                                 DBG("ltt_do_get_subbuf: error: %s", strerror(-result));
 189                         }
 190                         asprintf(&reply, "%s %ld", "OK", consumed_old);
 191                         result = ustcomm_send_reply(&bc->server, reply, &bc->src);
 192                         if(result < 0) {
 193                                 ERR("ustcomm_send_reply failed");
 194                                 free(reply);
 195                                 continue;
 196                         }
 197                         free(reply);
 198
 199                         list_del(&bc->list);
 200                 }
 201         }
 202
 203 }
 204
 205 void *listener_main(void *p)
 206 {
 207         int result;
 208
 209         DBG("LISTENER");
 210
 211         for(;;) {
 212                 char trace_name[] = "auto";
 213                 char trace_type[] = "ustrelay";
 214                 char *recvbuf;
 215                 int len;
 216                 struct ustcomm_source src;
 217
 218                 process_blocked_consumers();
 219
 220                 result = ustcomm_app_recv_message(&ustcomm_app, &recvbuf, &src, 5);
 221                 if(result < 0) {
 222                         WARN("error in ustcomm_app_recv_message");
 223                         continue;
 224                 }
 225                 else if(result == 0) {
 226                         /* no message */
 227                         continue;
 228                 }
 229
 230                 DBG("received a message! it's: %s\n", recvbuf);
 231                 len = strlen(recvbuf);
 232
 233                 if(!strcmp(recvbuf, "print_markers")) {
 234                         print_markers(stderr);
 235                 }
 236                 else if(!strcmp(recvbuf, "list_markers")) {
 237                         char *ptr;
 238                         size_t size;
 239                         FILE *fp;
 240
 241                         fp = open_memstream(&ptr, &size);
 242                         print_markers(fp);
 243                         fclose(fp);
 244
 245                         result = ustcomm_send_reply(&ustcomm_app.server, ptr, &src);
 246
 247                         free(ptr);
 248                 }
 249                 else if(!strcmp(recvbuf, "start")) {
 250                         /* start is an operation that setups the trace, allocates it and starts it */
 251                         result = ltt_trace_setup(trace_name);
 252                         if(result < 0) {
 253                                 ERR("ltt_trace_setup failed");
 254                                 return (void *)1;
 255                         }
 256
 257                         result = ltt_trace_set_type(trace_name, trace_type);
 258                         if(result < 0) {
 259                                 ERR("ltt_trace_set_type failed");
 260                                 return (void *)1;
 261                         }
 262
 263                         result = ltt_trace_alloc(trace_name);
 264                         if(result < 0) {
 265                                 ERR("ltt_trace_alloc failed");
 266                                 return (void *)1;
 267                         }
 268
 269                         inform_consumer_daemon();
 270
 271                         result = ltt_trace_start(trace_name);
 272                         if(result < 0) {
 273                                 ERR("ltt_trace_start failed");
 274                                 continue;
 275                         }
 276                 }
 277                 else if(!strcmp(recvbuf, "trace_setup")) {
 278                         DBG("trace setup");
 279
 280                         result = ltt_trace_setup(trace_name);
 281                         if(result < 0) {
 282                                 ERR("ltt_trace_setup failed");
 283                                 return (void *)1;
 284                         }
 285
 286                         result = ltt_trace_set_type(trace_name, trace_type);
 287                         if(result < 0) {
 288                                 ERR("ltt_trace_set_type failed");
 289                                 return (void *)1;
 290                         }
 291                 }
 292                 else if(!strcmp(recvbuf, "trace_alloc")) {
 293                         DBG("trace alloc");
 294
 295                         result = ltt_trace_alloc(trace_name);
 296                         if(result < 0) {
 297                                 ERR("ltt_trace_alloc failed");
 298                                 return (void *)1;
 299                         }
 300                 }
 301                 else if(!strcmp(recvbuf, "trace_start")) {
 302                         DBG("trace start");
 303
 304                         result = ltt_trace_start(trace_name);
 305                         if(result < 0) {
 306                                 ERR("ltt_trace_start failed");
 307                                 continue;
 308                         }
 309                 }
 310                 else if(!strcmp(recvbuf, "trace_stop")) {
 311                         DBG("trace stop");
 312
 313                         result = ltt_trace_stop(trace_name);
 314                         if(result < 0) {
 315                                 ERR("ltt_trace_stop failed");
 316                                 return (void *)1;
 317                         }
 318                 }
 319                 else if(!strcmp(recvbuf, "trace_destroy")) {
 320
 321                         DBG("trace destroy");
 322
 323                         result = ltt_trace_destroy(trace_name);
 324                         if(result < 0) {
 325                                 ERR("ltt_trace_destroy failed");
 326                                 return (void *)1;
 327                         }
 328                 }
 329                 else if(nth_token_is(recvbuf, "get_shmid", 0) == 1) {
 330                         struct ltt_trace_struct *trace;
 331                         char trace_name[] = "auto";
 332                         int i;
 333                         char *channel_name;
 334
 335                         DBG("get_shmid");
 336
 337                         channel_name = nth_token(recvbuf, 1);
 338                         if(channel_name == NULL) {
 339                                 ERR("get_shmid: cannot parse channel");
 340                                 goto next_cmd;
 341                         }
 342
 343                         ltt_lock_traces();
 344                         trace = _ltt_trace_find(trace_name);
 345                         ltt_unlock_traces();
 346
 347                         if(trace == NULL) {
 348                                 ERR("cannot find trace!");
 349                                 return (void *)1;
 350                         }
 351
 352                         for(i=0; i<trace->nr_channels; i++) {
 353                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 354                                 struct rchan_buf *rbuf = rchan->buf;
 355                                 struct ltt_channel_struct *ltt_channel = (struct ltt_channel_struct *)rchan->private_data;
 356
 357                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 358                                         char *reply;
 359
 360                                         DBG("the shmid for the requested channel is %d", rbuf->shmid);
 361                                         DBG("the shmid for its buffer structure is %d", ltt_channel->buf_shmid);
 362                                         asprintf(&reply, "%d %d", rbuf->shmid, ltt_channel->buf_shmid);
 363
 364                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 365                                         if(result) {
 366                                                 ERR("listener: get_shmid: ustcomm_send_reply failed");
 367                                                 goto next_cmd;
 368                                         }
 369
 370                                         free(reply);
 371
 372                                         break;
 373                                 }
 374                         }
 375                 }
 376                 else if(nth_token_is(recvbuf, "get_n_subbufs", 0) == 1) {
 377                         struct ltt_trace_struct *trace;
 378                         char trace_name[] = "auto";
 379                         int i;
 380                         char *channel_name;
 381
 382                         DBG("get_n_subbufs");
 383
 384                         channel_name = nth_token(recvbuf, 1);
 385                         if(channel_name == NULL) {
 386                                 ERR("get_n_subbufs: cannot parse channel");
 387                                 goto next_cmd;
 388                         }
 389
 390                         ltt_lock_traces();
 391                         trace = _ltt_trace_find(trace_name);
 392                         ltt_unlock_traces();
 393
 394                         if(trace == NULL) {
 395                                 ERR("cannot find trace!");
 396                                 return (void *)1;
 397                         }
 398
 399                         for(i=0; i<trace->nr_channels; i++) {
 400                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 401
 402                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 403                                         char *reply;
 404
 405                                         DBG("the n_subbufs for the requested channel is %zd", rchan->n_subbufs);
 406                                         asprintf(&reply, "%zd", rchan->n_subbufs);
 407
 408                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 409                                         if(result) {
 410                                                 ERR("listener: get_n_subbufs: ustcomm_send_reply failed");
 411                                                 goto next_cmd;
 412                                         }
 413
 414                                         free(reply);
 415
 416                                         break;
 417                                 }
 418                         }
 419                 }
 420                 else if(nth_token_is(recvbuf, "get_subbuf_size", 0) == 1) {
 421                         struct ltt_trace_struct *trace;
 422                         char trace_name[] = "auto";
 423                         int i;
 424                         char *channel_name;
 425
 426                         DBG("get_subbuf_size");
 427
 428                         channel_name = nth_token(recvbuf, 1);
 429                         if(channel_name == NULL) {
 430                                 ERR("get_subbuf_size: cannot parse channel");
 431                                 goto next_cmd;
 432                         }
 433
 434                         ltt_lock_traces();
 435                         trace = _ltt_trace_find(trace_name);
 436                         ltt_unlock_traces();
 437
 438                         if(trace == NULL) {
 439                                 ERR("cannot find trace!");
 440                                 return (void *)1;
 441                         }
 442
 443                         for(i=0; i<trace->nr_channels; i++) {
 444                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 445
 446                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 447                                         char *reply;
 448
 449                                         DBG("the subbuf_size for the requested channel is %zd", rchan->subbuf_size);
 450                                         asprintf(&reply, "%zd", rchan->subbuf_size);
 451
 452                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 453                                         if(result) {
 454                                                 ERR("listener: get_subbuf_size: ustcomm_send_reply failed");
 455                                                 goto next_cmd;
 456                                         }
 457
 458                                         free(reply);
 459
 460                                         break;
 461                                 }
 462                         }
 463                 }
 464                 else if(nth_token_is(recvbuf, "load_probe_lib", 0) == 1) {
 465                         char *libfile;
 466
 467                         libfile = nth_token(recvbuf, 1);
 468
 469                         DBG("load_probe_lib loading %s", libfile);
 470                 }
 471                 else if(nth_token_is(recvbuf, "get_subbuffer", 0) == 1) {
 472                         struct ltt_trace_struct *trace;
 473                         char trace_name[] = "auto";
 474                         int i;
 475                         char *channel_name;
 476
 477                         DBG("get_subbuf");
 478
 479                         channel_name = nth_token(recvbuf, 1);
 480                         if(channel_name == NULL) {
 481                                 ERR("get_subbuf: cannot parse channel");
 482                                 goto next_cmd;
 483                         }
 484
 485                         ltt_lock_traces();
 486                         trace = _ltt_trace_find(trace_name);
 487                         ltt_unlock_traces();
 488
 489                         if(trace == NULL) {
 490                                 ERR("cannot find trace!");
 491                                 return (void *)1;
 492                         }
 493
 494                         for(i=0; i<trace->nr_channels; i++) {
 495                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 496
 497                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 498                                         struct rchan_buf *rbuf = rchan->buf;
 499                                         struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 500                                         struct blocked_consumer *bc;
 501
 502                                         bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
 503                                         if(bc == NULL) {
 504                                                 ERR("malloc returned NULL");
 505                                                 goto next_cmd;
 506                                         }
 507                                         bc->fd_consumer = src.fd;
 508                                         bc->fd_producer = lttbuf->data_ready_fd_read;
 509                                         bc->rbuf = rbuf;
 510                                         bc->lttbuf = lttbuf;
 511                                         bc->src = src;
 512                                         bc->server = ustcomm_app.server;
 513
 514                                         list_add(&bc->list, &blocked_consumers);
 515
 516                                         break;
 517                                 }
 518                         }
 519                 }
 520                 else if(nth_token_is(recvbuf, "put_subbuffer", 0) == 1) {
 521                         struct ltt_trace_struct *trace;
 522                         char trace_name[] = "auto";
 523                         int i;
 524                         char *channel_name;
 525                         long consumed_old;
 526                         char *consumed_old_str;
 527                         char *endptr;
 528
 529                         DBG("put_subbuf");
 530
 531                         channel_name = strdup_malloc(nth_token(recvbuf, 1));
 532                         if(channel_name == NULL) {
 533                                 ERR("put_subbuf_size: cannot parse channel");
 534                                 goto next_cmd;
 535                         }
 536
 537                         consumed_old_str = strdup_malloc(nth_token(recvbuf, 2));
 538                         if(consumed_old_str == NULL) {
 539                                 ERR("put_subbuf: cannot parse consumed_old");
 540                                 goto next_cmd;
 541                         }
 542                         consumed_old = strtol(consumed_old_str, &endptr, 10);
 543                         if(*endptr != '\0') {
 544                                 ERR("put_subbuf: invalid value for consumed_old");
 545                                 goto next_cmd;
 546                         }
 547
 548                         ltt_lock_traces();
 549                         trace = _ltt_trace_find(trace_name);
 550                         ltt_unlock_traces();
 551
 552                         if(trace == NULL) {
 553                                 ERR("cannot find trace!");
 554                                 return (void *)1;
 555                         }
 556
 557                         for(i=0; i<trace->nr_channels; i++) {
 558                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 559
 560                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 561                                         struct rchan_buf *rbuf = rchan->buf;
 562                                         struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 563                                         char *reply;
 564                                         long consumed_old=0;
 565
 566                                         result = ltt_do_put_subbuf(rbuf, lttbuf, consumed_old);
 567                                         if(result < 0) {
 568                                                 WARN("ltt_do_put_subbuf: error (subbuf=%s)", channel_name);
 569                                                 asprintf(&reply, "%s", "ERROR");
 570                                         }
 571                                         else {
 572                                                 DBG("ltt_do_put_subbuf: success (subbuf=%s)", channel_name);
 573                                                 asprintf(&reply, "%s", "OK");
 574                                         }
 575
 576                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 577                                         if(result) {
 578                                                 ERR("listener: put_subbuf: ustcomm_send_reply failed");
 579                                                 goto next_cmd;
 580                                         }
 581
 582                                         free(reply);
 583
 584                                         break;
 585                                 }
 586                         }
 587
 588                         free(channel_name);
 589                         free(consumed_old_str);
 590                 }
 591                 else if(nth_token_is(recvbuf, "enable_marker", 0) == 1) {
 592                         char *channel_slash_name = nth_token(recvbuf, 1);
 593                         char channel_name[256]="";
 594                         char marker_name[256]="";
 595
 596                         result = sscanf(channel_slash_name, "%255[^/]/%255s", channel_name, marker_name);
 597
 598                         if(channel_name == NULL || marker_name == NULL) {
 599                                 WARN("invalid marker name");
 600                                 goto next_cmd;
 601                         }
 602                         printf("%s %s\n", channel_name, marker_name);
 603
 604                         result = ltt_marker_connect(channel_name, marker_name, "default");
 605                         if(result < 0) {
 606                                 WARN("could not enable marker; channel=%s, name=%s", channel_name, marker_name);
 607                         }
 608                 }
 609                 else if(nth_token_is(recvbuf, "disable_marker", 0) == 1) {
 610                         char *channel_slash_name = nth_token(recvbuf, 1);
 611                         char *marker_name;
 612                         char *channel_name;
 613
 614                         result = sscanf(channel_slash_name, "%a[^/]/%as", &channel_name, &marker_name);
 615
 616                         if(marker_name == NULL) {
 617                         }
 618                         printf("%s %s\n", channel_name, marker_name);
 619
 620                         result = ltt_marker_disconnect(channel_name, marker_name, "default");
 621                         if(result < 0) {
 622                                 WARN("could not disable marker; channel=%s, name=%s", channel_name, marker_name);
 623                         }
 624                 }
 625 //              else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
 626 //                      struct ltt_trace_struct *trace;
 627 //                      char trace_name[] = "auto";
 628 //                      int i;
 629 //                      char *channel_name;
 630 //
 631 //                      DBG("get_notifications");
 632 //
 633 //                      channel_name = strdup_malloc(nth_token(recvbuf, 1));
 634 //                      if(channel_name == NULL) {
 635 //                              ERR("put_subbuf_size: cannot parse channel");
 636 //                              goto next_cmd;
 637 //                      }
 638 //
 639 //                      ltt_lock_traces();
 640 //                      trace = _ltt_trace_find(trace_name);
 641 //                      ltt_unlock_traces();
 642 //
 643 //                      if(trace == NULL) {
 644 //                              ERR("cannot find trace!");
 645 //                              return (void *)1;
 646 //                      }
 647 //
 648 //                      for(i=0; i<trace->nr_channels; i++) {
 649 //                              struct rchan *rchan = trace->channels[i].trans_channel_data;
 650 //                              int fd;
 651 //
 652 //                              if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 653 //                                      struct rchan_buf *rbuf = rchan->buf;
 654 //                                      struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 655 //
 656 //                                      result = fd = ustcomm_app_detach_client(&ustcomm_app, &src);
 657 //                                      if(result == -1) {
 658 //                                              ERR("ustcomm_app_detach_client failed");
 659 //                                              goto next_cmd;
 660 //                                      }
 661 //
 662 //                                      lttbuf->wake_consumer_arg = (void *) fd;
 663 //
 664 //                                      smp_wmb();
 665 //
 666 //                                      lttbuf->call_wake_consumer = 1;
 667 //
 668 //                                      break;
 669 //                              }
 670 //                      }
 671 //
 672 //                      free(channel_name);
 673 //              }
 674                 else {
 675                         ERR("unable to parse message: %s", recvbuf);
 676                 }
 677
 678         next_cmd:
 679                 free(recvbuf);
 680         }
 681 }
 682
 683 void create_listener(void)
 684 {
 685 #ifdef USE_CLONE
 686         static char listener_stack[16384];
 687 #endif
 688
 689 #ifdef USE_CLONE
 690         result = clone(listener_main, listener_stack+sizeof(listener_stack)-1, CLONE_FS | CLONE_FILES | CLONE_VM | CLONE_SIGHAND | CLONE_THREAD, NULL);
 691         if(result == -1) {
 692                 perror("clone");
 693         }
 694 #else
 695         pthread_t thread;
 696
 697         pthread_create(&thread, NULL, listener_main, NULL);
 698 #endif
 699 }
 700
 701 /* The signal handler itself. Signals must be setup so there cannot be
 702    nested signals. */
 703
 704 void sighandler(int sig)
 705 {
 706         static char have_listener = 0;
 707         DBG("sighandler");
 708
 709         if(!have_listener) {
 710                 create_listener();
 711                 have_listener = 1;
 712         }
 713 }
 714
 715 /* Called by the app signal handler to chain it to us. */
 716
 717 void chain_signal(void)
 718 {
 719         sighandler(USTSIGNAL);
 720 }
 721
 722 static int init_socket(void)
 723 {
 724         return ustcomm_init_app(getpid(), &ustcomm_app);
 725 }
 726
 727 /* FIXME: reenable this to delete socket file. */
 728
 729 #if 0
 730 static void destroy_socket(void)
 731 {
 732         int result;
 733
 734         if(mysocketfile[0] == '\0')
 735                 return;
 736
 737         result = unlink(mysocketfile);
 738         if(result == -1) {
 739                 PERROR("unlink");
 740         }
 741 }
 742 #endif
 743
 744 static int init_signal_handler(void)
 745 {
 746         /* Attempt to handler SIGIO. If the main program wants to
 747          * handle it, fine, it'll override us. They it'll have to
 748          * use the chaining function.
 749          */
 750
 751         int result;
 752         struct sigaction act;
 753
 754         result = sigemptyset(&act.sa_mask);
 755         if(result == -1) {
 756                 PERROR("sigemptyset");
 757                 return -1;
 758         }
 759
 760         act.sa_handler = sighandler;
 761         act.sa_flags = SA_RESTART;
 762
 763         /* Only defer ourselves. Also, try to restart interrupted
 764          * syscalls to disturb the traced program as little as possible.
 765          */
 766         result = sigaction(SIGIO, &act, NULL);
 767         if(result == -1) {
 768                 PERROR("sigaction");
 769                 return -1;
 770         }
 771
 772         return 0;
 773 }
 774
 775 static void auto_probe_connect(struct marker *m)
 776 {
 777         int result;
 778
 779         result = ltt_marker_connect(m->channel, m->name, "default");
 780         if(result && result != -EEXIST)
 781                 ERR("ltt_marker_connect (marker = %s/%s, errno = %d)", m->channel, m->name, -result);
 782
 783         DBG("just auto connected marker %s %s to probe default", m->channel, m->name);
 784 }
 785
 786 static void __attribute__((constructor(101))) init0()
 787 {
 788         DBG("UST_AUTOPROBE constructor");
 789         if(getenv("UST_AUTOPROBE")) {
 790                 marker_set_new_marker_cb(auto_probe_connect);
 791         }
 792 }
 793
 794 static void __attribute__((constructor(1000))) init()
 795 {
 796         int result;
 797
 798         DBG("UST_TRACE constructor");
 799
 800         /* Must create socket before signal handler to prevent races.
 801          */
 802         result = init_socket();
 803         if(result == -1) {
 804                 ERR("init_socket error");
 805                 return;
 806         }
 807         result = init_signal_handler();
 808         if(result == -1) {
 809                 ERR("init_signal_handler error");
 810                 return;
 811         }
 812
 813         if(getenv("UST_TRACE")) {
 814                 char trace_name[] = "auto";
 815                 char trace_type[] = "ustrelay";
 816
 817                 DBG("starting early tracing");
 818
 819                 /* Ensure marker control is initialized */
 820                 init_marker_control();
 821
 822                 /* Ensure relay is initialized */
 823                 init_ustrelay_transport();
 824
 825                 /* Ensure markers are initialized */
 826                 init_markers();
 827
 828                 /* In case. */
 829                 ltt_channels_register("ust");
 830
 831                 result = ltt_trace_setup(trace_name);
 832                 if(result < 0) {
 833                         ERR("ltt_trace_setup failed");
 834                         return;
 835                 }
 836
 837                 result = ltt_trace_set_type(trace_name, trace_type);
 838                 if(result < 0) {
 839                         ERR("ltt_trace_set_type failed");
 840                         return;
 841                 }
 842
 843                 result = ltt_trace_alloc(trace_name);
 844                 if(result < 0) {
 845                         ERR("ltt_trace_alloc failed");
 846                         return;
 847                 }
 848
 849                 result = ltt_trace_start(trace_name);
 850                 if(result < 0) {
 851                         ERR("ltt_trace_start failed");
 852                         return;
 853                 }
 854                 inform_consumer_daemon();
 855         }
 856
 857
 858         return;
 859
 860         /* should decrementally destroy stuff if error */
 861
 862 }
 863
 864 /* This is only called if we terminate normally, not with an unhandled signal,
 865  * so we cannot rely on it. */
 866
 867 /* This destructor probably isn't needed, because ustd can do crash recovery. */
 868 #if 0
 869 static void __attribute__((destructor)) fini()
 870 {
 871         int result;
 872
 873         /* if trace running, finish it */
 874
 875         DBG("destructor stopping traces");
 876
 877         result = ltt_trace_stop("auto");
 878         if(result == -1) {
 879                 ERR("ltt_trace_stop error");
 880         }
 881
 882         result = ltt_trace_destroy("auto");
 883         if(result == -1) {
 884                 ERR("ltt_trace_destroy error");
 885         }
 886
 887         destroy_socket();
 888 }
 889 #endif