libust/tracectl.c

   1 #include <stdio.h>
   2 #include <stdint.h>
   3 #include <signal.h>
   4 #include <sys/types.h>
   5 #include <sys/socket.h>
   6 #include <sys/un.h>
   7 #include <sched.h>
   8 #include <fcntl.h>
   9 #include <poll.h>
  10
  11 #include "marker.h"
  12 #include "tracer.h"
  13 #include "localerr.h"
  14 #include "ustcomm.h"
  15 #include "relay.h" /* FIXME: remove */
  16
  17 //#define USE_CLONE
  18
  19 #define USTSIGNAL SIGIO
  20
  21 #define MAX_MSG_SIZE (100)
  22 #define MSG_NOTIF 1
  23 #define MSG_REGISTER_NOTIF 2
  24
  25 char consumer_stack[10000];
  26
  27 struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
  28
  29 static struct ustcomm_app ustcomm_app;
  30
  31 struct tracecmd { /* no padding */
  32         uint32_t size;
  33         uint16_t command;
  34 };
  35
  36 //struct listener_arg {
  37 //      int pipe_fd;
  38 //};
  39
  40 struct trctl_msg {
  41         /* size: the size of all the fields except size itself */
  42         uint32_t size;
  43         uint16_t type;
  44         /* Only the necessary part of the payload is transferred. It
  45          * may even be none of it.
  46          */
  47         char payload[94];
  48 };
  49
  50 struct consumer_channel {
  51         int fd;
  52         struct ltt_channel_struct *chan;
  53 };
  54
  55 struct blocked_consumer {
  56         int fd_consumer;
  57         int fd_producer;
  58         int tmp_poll_idx;
  59
  60         /* args to ustcomm_send_reply */
  61         struct ustcomm_server server;
  62         struct ustcomm_source src;
  63
  64         /* args to ltt_do_get_subbuf */
  65         struct rchan_buf *rbuf;
  66         struct ltt_channel_buf_struct *lttbuf;
  67
  68         struct list_head list;
  69 };
  70
  71 static void print_markers(FILE *fp)
  72 {
  73         struct marker_iter iter;
  74
  75         lock_markers();
  76         marker_iter_reset(&iter);
  77         marker_iter_start(&iter);
  78
  79         while(iter.marker) {
  80                 fprintf(fp, "marker: %s_%s %d \"%s\"\n", iter.marker->channel, iter.marker->name, (int)imv_read(iter.marker->state), iter.marker->format);
  81                 marker_iter_next(&iter);
  82         }
  83         unlock_markers();
  84 }
  85
  86 void do_command(struct tracecmd *cmd)
  87 {
  88 }
  89
  90 void receive_commands()
  91 {
  92 }
  93
  94 int fd_notif = -1;
  95 void notif_cb(void)
  96 {
  97         int result;
  98         struct trctl_msg msg;
  99
 100         /* FIXME: fd_notif should probably be protected by a spinlock */
 101
 102         if(fd_notif == -1)
 103                 return;
 104
 105         msg.type = MSG_NOTIF;
 106         msg.size = sizeof(msg.type);
 107
 108         /* FIXME: don't block here */
 109         result = write(fd_notif, &msg, msg.size+sizeof(msg.size));
 110         if(result == -1) {
 111                 PERROR("write");
 112                 return;
 113         }
 114 }
 115
 116 static int inform_consumer_daemon(void)
 117 {
 118         ustcomm_request_consumer(getpid(), "metadata");
 119         ustcomm_request_consumer(getpid(), "ust");
 120 }
 121
 122 void process_blocked_consumers(void)
 123 {
 124         int n_fds = 0;
 125         struct pollfd *fds;
 126         struct blocked_consumer *bc;
 127         int idx = 0;
 128         char inbuf;
 129         int result;
 130
 131         list_for_each_entry(bc, &blocked_consumers, list) {
 132                 n_fds++;
 133         }
 134
 135         fds = (struct pollfd *) malloc(n_fds * sizeof(struct pollfd));
 136         if(fds == NULL) {
 137                 ERR("malloc returned NULL");
 138                 return;
 139         }
 140
 141         list_for_each_entry(bc, &blocked_consumers, list) {
 142                 fds[idx].fd = bc->fd_producer;
 143                 fds[idx].events = POLLIN;
 144                 bc->tmp_poll_idx = idx;
 145                 idx++;
 146         }
 147
 148         result = poll(fds, n_fds, 0);
 149         if(result == -1) {
 150                 PERROR("poll");
 151                 return -1;
 152         }
 153
 154         list_for_each_entry(bc, &blocked_consumers, list) {
 155                 if(fds[bc->tmp_poll_idx].revents) {
 156                         long consumed_old = 0;
 157                         char *reply;
 158
 159                         result = read(bc->fd_producer, &inbuf, 1);
 160                         if(result == -1) {
 161                                 PERROR("read");
 162                                 continue;
 163                         }
 164                         if(result == 0) {
 165                                 DBG("PRODUCER END");
 166
 167                                 close(bc->fd_producer);
 168
 169                                 __list_del(bc->list.prev, bc->list.next);
 170
 171                                 result = ustcomm_send_reply(&bc->server, "END", &bc->src);
 172                                 if(result < 0) {
 173                                         ERR("ustcomm_send_reply failed");
 174                                         continue;
 175                                 }
 176
 177                                 continue;
 178                         }
 179
 180                         result = ltt_do_get_subbuf(bc->rbuf, bc->lttbuf, &consumed_old);
 181                         if(result == -EAGAIN) {
 182                                 WARN("missed buffer?");
 183                                 continue;
 184                         }
 185                         else if(result < 0) {
 186                                 DBG("ltt_do_get_subbuf: error: %s", strerror(-result));
 187                         }
 188                         asprintf(&reply, "%s %ld", "OK", consumed_old);
 189                         result = ustcomm_send_reply(&bc->server, reply, &bc->src);
 190                         if(result < 0) {
 191                                 ERR("ustcomm_send_reply failed");
 192                                 free(reply);
 193                                 continue;
 194                         }
 195                         free(reply);
 196
 197                         __list_del(bc->list.prev, bc->list.next);
 198                 }
 199         }
 200
 201 }
 202
 203 int listener_main(void *p)
 204 {
 205         int result;
 206
 207         DBG("LISTENER");
 208
 209         for(;;) {
 210                 uint32_t size;
 211                 struct sockaddr_un addr;
 212                 socklen_t addrlen = sizeof(addr);
 213                 char trace_name[] = "auto";
 214                 char trace_type[] = "ustrelay";
 215                 char *recvbuf;
 216                 int len;
 217                 struct ustcomm_source src;
 218
 219                 process_blocked_consumers();
 220
 221                 result = ustcomm_app_recv_message(&ustcomm_app, &recvbuf, &src, 5);
 222                 if(result < 0) {
 223                         WARN("error in ustcomm_app_recv_message");
 224                         continue;
 225                 }
 226                 else if(result == 0) {
 227                         /* no message */
 228                         continue;
 229                 }
 230
 231                 DBG("received a message! it's: %s\n", recvbuf);
 232                 len = strlen(recvbuf);
 233
 234                 if(!strcmp(recvbuf, "print_markers")) {
 235                         print_markers(stderr);
 236                 }
 237                 else if(!strcmp(recvbuf, "list_markers")) {
 238                         char *ptr;
 239                         size_t size;
 240                         FILE *fp;
 241
 242                         fp = open_memstream(&ptr, &size);
 243                         print_markers(fp);
 244                         fclose(fp);
 245
 246                         result = ustcomm_send_reply(&ustcomm_app.server, ptr, &src);
 247
 248                         free(ptr);
 249                 }
 250                 else if(!strcmp(recvbuf, "start")) {
 251                         /* start is an operation that setups the trace, allocates it and starts it */
 252                         result = ltt_trace_setup(trace_name);
 253                         if(result < 0) {
 254                                 ERR("ltt_trace_setup failed");
 255                                 return;
 256                         }
 257
 258                         result = ltt_trace_set_type(trace_name, trace_type);
 259                         if(result < 0) {
 260                                 ERR("ltt_trace_set_type failed");
 261                                 return;
 262                         }
 263
 264                         result = ltt_trace_alloc(trace_name);
 265                         if(result < 0) {
 266                                 ERR("ltt_trace_alloc failed");
 267                                 return;
 268                         }
 269
 270                         inform_consumer_daemon();
 271
 272                         result = ltt_trace_start(trace_name);
 273                         if(result < 0) {
 274                                 ERR("ltt_trace_start failed");
 275                                 continue;
 276                         }
 277                 }
 278                 else if(!strcmp(recvbuf, "trace_setup")) {
 279                         DBG("trace setup");
 280
 281                         result = ltt_trace_setup(trace_name);
 282                         if(result < 0) {
 283                                 ERR("ltt_trace_setup failed");
 284                                 return;
 285                         }
 286
 287                         result = ltt_trace_set_type(trace_name, trace_type);
 288                         if(result < 0) {
 289                                 ERR("ltt_trace_set_type failed");
 290                                 return;
 291                         }
 292                 }
 293                 else if(!strcmp(recvbuf, "trace_alloc")) {
 294                         DBG("trace alloc");
 295
 296                         result = ltt_trace_alloc(trace_name);
 297                         if(result < 0) {
 298                                 ERR("ltt_trace_alloc failed");
 299                                 return;
 300                         }
 301                 }
 302                 else if(!strcmp(recvbuf, "trace_start")) {
 303                         DBG("trace start");
 304
 305                         result = ltt_trace_start(trace_name);
 306                         if(result < 0) {
 307                                 ERR("ltt_trace_start failed");
 308                                 continue;
 309                         }
 310                 }
 311                 else if(!strcmp(recvbuf, "trace_stop")) {
 312                         DBG("trace stop");
 313
 314                         result = ltt_trace_stop(trace_name);
 315                         if(result < 0) {
 316                                 ERR("ltt_trace_stop failed");
 317                                 return;
 318                         }
 319                 }
 320                 else if(!strcmp(recvbuf, "trace_destroy")) {
 321
 322                         DBG("trace destroy");
 323
 324                         result = ltt_trace_destroy(trace_name);
 325                         if(result < 0) {
 326                                 ERR("ltt_trace_destroy failed");
 327                                 return;
 328                         }
 329                 }
 330                 else if(nth_token_is(recvbuf, "get_shmid", 0) == 1) {
 331                         struct ltt_trace_struct *trace;
 332                         char trace_name[] = "auto";
 333                         int i;
 334                         char *channel_name;
 335
 336                         DBG("get_shmid");
 337
 338                         channel_name = nth_token(recvbuf, 1);
 339                         if(channel_name == NULL) {
 340                                 ERR("get_shmid: cannot parse channel");
 341                                 goto next_cmd;
 342                         }
 343
 344                         ltt_lock_traces();
 345                         trace = _ltt_trace_find(trace_name);
 346                         ltt_unlock_traces();
 347
 348                         if(trace == NULL) {
 349                                 CPRINTF("cannot find trace!");
 350                                 return 1;
 351                         }
 352
 353                         for(i=0; i<trace->nr_channels; i++) {
 354                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 355                                 struct rchan_buf *rbuf = rchan->buf;
 356                                 struct ltt_channel_struct *ltt_channel = (struct ltt_channel_struct *)rchan->private_data;
 357                                 struct ltt_channel_buf_struct *ltt_buf = ltt_channel->buf;
 358
 359                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 360                                         char *reply;
 361
 362                                         DBG("the shmid for the requested channel is %d", rbuf->shmid);
 363                                         DBG("the shmid for its buffer structure is %d", ltt_channel->buf_shmid);
 364                                         asprintf(&reply, "%d %d", rbuf->shmid, ltt_channel->buf_shmid);
 365
 366                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 367                                         if(result) {
 368                                                 ERR("listener: get_shmid: ustcomm_send_reply failed");
 369                                                 goto next_cmd;
 370                                         }
 371
 372                                         free(reply);
 373
 374                                         break;
 375                                 }
 376                         }
 377                 }
 378                 else if(nth_token_is(recvbuf, "get_n_subbufs", 0) == 1) {
 379                         struct ltt_trace_struct *trace;
 380                         char trace_name[] = "auto";
 381                         int i;
 382                         char *channel_name;
 383
 384                         DBG("get_n_subbufs");
 385
 386                         channel_name = nth_token(recvbuf, 1);
 387                         if(channel_name == NULL) {
 388                                 ERR("get_n_subbufs: cannot parse channel");
 389                                 goto next_cmd;
 390                         }
 391
 392                         ltt_lock_traces();
 393                         trace = _ltt_trace_find(trace_name);
 394                         ltt_unlock_traces();
 395
 396                         if(trace == NULL) {
 397                                 CPRINTF("cannot find trace!");
 398                                 return 1;
 399                         }
 400
 401                         for(i=0; i<trace->nr_channels; i++) {
 402                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 403
 404                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 405                                         char *reply;
 406
 407                                         DBG("the n_subbufs for the requested channel is %d", rchan->n_subbufs);
 408                                         asprintf(&reply, "%d", rchan->n_subbufs);
 409
 410                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 411                                         if(result) {
 412                                                 ERR("listener: get_n_subbufs: ustcomm_send_reply failed");
 413                                                 goto next_cmd;
 414                                         }
 415
 416                                         free(reply);
 417
 418                                         break;
 419                                 }
 420                         }
 421                 }
 422                 else if(nth_token_is(recvbuf, "get_subbuf_size", 0) == 1) {
 423                         struct ltt_trace_struct *trace;
 424                         char trace_name[] = "auto";
 425                         int i;
 426                         char *channel_name;
 427
 428                         DBG("get_subbuf_size");
 429
 430                         channel_name = nth_token(recvbuf, 1);
 431                         if(channel_name == NULL) {
 432                                 ERR("get_subbuf_size: cannot parse channel");
 433                                 goto next_cmd;
 434                         }
 435
 436                         ltt_lock_traces();
 437                         trace = _ltt_trace_find(trace_name);
 438                         ltt_unlock_traces();
 439
 440                         if(trace == NULL) {
 441                                 CPRINTF("cannot find trace!");
 442                                 return 1;
 443                         }
 444
 445                         for(i=0; i<trace->nr_channels; i++) {
 446                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 447
 448                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 449                                         char *reply;
 450
 451                                         DBG("the subbuf_size for the requested channel is %d", rchan->subbuf_size);
 452                                         asprintf(&reply, "%d", rchan->subbuf_size);
 453
 454                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 455                                         if(result) {
 456                                                 ERR("listener: get_subbuf_size: ustcomm_send_reply failed");
 457                                                 goto next_cmd;
 458                                         }
 459
 460                                         free(reply);
 461
 462                                         break;
 463                                 }
 464                         }
 465                 }
 466                 else if(nth_token_is(recvbuf, "load_probe_lib", 0) == 1) {
 467                         char *libfile;
 468
 469                         libfile = nth_token(recvbuf, 1);
 470
 471                         DBG("load_probe_lib loading %s", libfile);
 472                 }
 473                 else if(nth_token_is(recvbuf, "get_subbuffer", 0) == 1) {
 474                         struct ltt_trace_struct *trace;
 475                         char trace_name[] = "auto";
 476                         int i;
 477                         char *channel_name;
 478
 479                         DBG("get_subbuf");
 480
 481                         channel_name = nth_token(recvbuf, 1);
 482                         if(channel_name == NULL) {
 483                                 ERR("get_subbuf: cannot parse channel");
 484                                 goto next_cmd;
 485                         }
 486
 487                         ltt_lock_traces();
 488                         trace = _ltt_trace_find(trace_name);
 489                         ltt_unlock_traces();
 490
 491                         if(trace == NULL) {
 492                                 CPRINTF("cannot find trace!");
 493                                 return 1;
 494                         }
 495
 496                         for(i=0; i<trace->nr_channels; i++) {
 497                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 498
 499                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 500                                         struct rchan_buf *rbuf = rchan->buf;
 501                                         struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 502                                         char *reply;
 503                                         long consumed_old=0;
 504                                         int fd;
 505                                         struct blocked_consumer *bc;
 506
 507                                         bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
 508                                         if(bc == NULL) {
 509                                                 ERR("malloc returned NULL");
 510                                                 goto next_cmd;
 511                                         }
 512                                         bc->fd_consumer = src.fd;
 513                                         bc->fd_producer = lttbuf->data_ready_fd_read;
 514                                         bc->rbuf = rbuf;
 515                                         bc->lttbuf = lttbuf;
 516                                         bc->src = src;
 517                                         bc->server = ustcomm_app.server;
 518
 519                                         list_add(&bc->list, &blocked_consumers);
 520
 521                                         break;
 522                                 }
 523                         }
 524                 }
 525                 else if(nth_token_is(recvbuf, "put_subbuffer", 0) == 1) {
 526                         struct ltt_trace_struct *trace;
 527                         char trace_name[] = "auto";
 528                         int i;
 529                         char *channel_name;
 530                         long consumed_old;
 531                         char *consumed_old_str;
 532                         char *endptr;
 533
 534                         DBG("put_subbuf");
 535
 536                         channel_name = strdup_malloc(nth_token(recvbuf, 1));
 537                         if(channel_name == NULL) {
 538                                 ERR("put_subbuf_size: cannot parse channel");
 539                                 goto next_cmd;
 540                         }
 541
 542                         consumed_old_str = strdup_malloc(nth_token(recvbuf, 2));
 543                         if(consumed_old_str == NULL) {
 544                                 ERR("put_subbuf: cannot parse consumed_old");
 545                                 goto next_cmd;
 546                         }
 547                         consumed_old = strtol(consumed_old_str, &endptr, 10);
 548                         if(*endptr != '\0') {
 549                                 ERR("put_subbuf: invalid value for consumed_old");
 550                                 goto next_cmd;
 551                         }
 552
 553                         ltt_lock_traces();
 554                         trace = _ltt_trace_find(trace_name);
 555                         ltt_unlock_traces();
 556
 557                         if(trace == NULL) {
 558                                 CPRINTF("cannot find trace!");
 559                                 return 1;
 560                         }
 561
 562                         for(i=0; i<trace->nr_channels; i++) {
 563                                 struct rchan *rchan = trace->channels[i].trans_channel_data;
 564
 565                                 if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 566                                         struct rchan_buf *rbuf = rchan->buf;
 567                                         struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 568                                         char *reply;
 569                                         long consumed_old=0;
 570
 571                                         result = ltt_do_put_subbuf(rbuf, lttbuf, consumed_old);
 572                                         if(result < 0) {
 573                                                 WARN("ltt_do_put_subbuf: error");
 574                                         }
 575                                         else {
 576                                                 DBG("ltt_do_put_subbuf: success");
 577                                         }
 578                                         asprintf(&reply, "%s", "OK", consumed_old);
 579
 580                                         result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
 581                                         if(result) {
 582                                                 ERR("listener: put_subbuf: ustcomm_send_reply failed");
 583                                                 goto next_cmd;
 584                                         }
 585
 586                                         free(reply);
 587
 588                                         break;
 589                                 }
 590                         }
 591
 592                         free(channel_name);
 593                         free(consumed_old_str);
 594                 }
 595                 else if(nth_token_is(recvbuf, "enable_marker", 0) == 1) {
 596                         char *channel_slash_name = nth_token(recvbuf, 1);
 597                         char channel_name[256]="";
 598                         char marker_name[256]="";
 599                         struct marker_iter iter;
 600
 601                         result = sscanf(channel_slash_name, "%255[^/]/%255s", channel_name, marker_name);
 602
 603                         if(channel_name == NULL || marker_name == NULL) {
 604                                 WARN("invalid marker name");
 605                                 goto next_cmd;
 606                         }
 607                         printf("%s %s\n", channel_name, marker_name);
 608
 609                         result = ltt_marker_connect(channel_name, marker_name, "default");
 610                         if(result < 0) {
 611                                 WARN("could not enable marker; channel=%s, name=%s", channel_name, marker_name);
 612                         }
 613                 }
 614                 else if(nth_token_is(recvbuf, "disable_marker", 0) == 1) {
 615                         char *channel_slash_name = nth_token(recvbuf, 1);
 616                         char *marker_name;
 617                         char *channel_name;
 618                         struct marker_iter iter;
 619
 620                         result = sscanf(channel_slash_name, "%a[^/]/%as", &channel_name, &marker_name);
 621
 622                         if(marker_name == NULL) {
 623                         }
 624                         printf("%s %s\n", channel_name, marker_name);
 625
 626                         result = ltt_marker_disconnect(channel_name, marker_name, "default");
 627                         if(result < 0) {
 628                                 WARN("could not disable marker; channel=%s, name=%s", channel_name, marker_name);
 629                         }
 630                 }
 631 //              else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
 632 //                      struct ltt_trace_struct *trace;
 633 //                      char trace_name[] = "auto";
 634 //                      int i;
 635 //                      char *channel_name;
 636 //
 637 //                      DBG("get_notifications");
 638 //
 639 //                      channel_name = strdup_malloc(nth_token(recvbuf, 1));
 640 //                      if(channel_name == NULL) {
 641 //                              ERR("put_subbuf_size: cannot parse channel");
 642 //                              goto next_cmd;
 643 //                      }
 644 //
 645 //                      ltt_lock_traces();
 646 //                      trace = _ltt_trace_find(trace_name);
 647 //                      ltt_unlock_traces();
 648 //
 649 //                      if(trace == NULL) {
 650 //                              CPRINTF("cannot find trace!");
 651 //                              return 1;
 652 //                      }
 653 //
 654 //                      for(i=0; i<trace->nr_channels; i++) {
 655 //                              struct rchan *rchan = trace->channels[i].trans_channel_data;
 656 //                              int fd;
 657 //
 658 //                              if(!strcmp(trace->channels[i].channel_name, channel_name)) {
 659 //                                      struct rchan_buf *rbuf = rchan->buf;
 660 //                                      struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
 661 //
 662 //                                      result = fd = ustcomm_app_detach_client(&ustcomm_app, &src);
 663 //                                      if(result == -1) {
 664 //                                              ERR("ustcomm_app_detach_client failed");
 665 //                                              goto next_cmd;
 666 //                                      }
 667 //
 668 //                                      lttbuf->wake_consumer_arg = (void *) fd;
 669 //
 670 //                                      smp_wmb();
 671 //
 672 //                                      lttbuf->call_wake_consumer = 1;
 673 //
 674 //                                      break;
 675 //                              }
 676 //                      }
 677 //
 678 //                      free(channel_name);
 679 //              }
 680                 else {
 681                         ERR("unable to parse message: %s", recvbuf);
 682                 }
 683
 684         next_cmd:
 685                 free(recvbuf);
 686         }
 687 }
 688
 689 static char listener_stack[16384];
 690
 691 void create_listener(void)
 692 {
 693         int result;
 694         static char listener_stack[16384];
 695         //char *listener_stack = malloc(16384);
 696
 697 #ifdef USE_CLONE
 698         result = clone(listener_main, listener_stack+sizeof(listener_stack)-1, CLONE_FS | CLONE_FILES | CLONE_VM | CLONE_SIGHAND | CLONE_THREAD, NULL);
 699         if(result == -1) {
 700                 perror("clone");
 701         }
 702 #else
 703         pthread_t thread;
 704
 705         pthread_create(&thread, NULL, listener_main, NULL);
 706 #endif
 707 }
 708
 709 /* The signal handler itself. Signals must be setup so there cannot be
 710    nested signals. */
 711
 712 void sighandler(int sig)
 713 {
 714         static char have_listener = 0;
 715         DBG("sighandler");
 716
 717         if(!have_listener) {
 718                 create_listener();
 719                 have_listener = 1;
 720         }
 721 }
 722
 723 /* Called by the app signal handler to chain it to us. */
 724
 725 void chain_signal(void)
 726 {
 727         sighandler(USTSIGNAL);
 728 }
 729
 730 static int init_socket(void)
 731 {
 732         return ustcomm_init_app(getpid(), &ustcomm_app);
 733 }
 734
 735 static void destroy_socket(void)
 736 {
 737 //      int result;
 738 //
 739 //      if(mysocketfile[0] == '\0')
 740 //              return;
 741 //
 742 //      result = unlink(mysocketfile);
 743 //      if(result == -1) {
 744 //              PERROR("unlink");
 745 //      }
 746 }
 747
 748 static int init_signal_handler(void)
 749 {
 750         /* Attempt to handler SIGIO. If the main program wants to
 751          * handle it, fine, it'll override us. They it'll have to
 752          * use the chaining function.
 753          */
 754
 755         int result;
 756         struct sigaction act;
 757
 758         result = sigemptyset(&act.sa_mask);
 759         if(result == -1) {
 760                 PERROR("sigemptyset");
 761                 return -1;
 762         }
 763
 764         act.sa_handler = sighandler;
 765         act.sa_flags = SA_RESTART;
 766
 767         /* Only defer ourselves. Also, try to restart interrupted
 768          * syscalls to disturb the traced program as little as possible.
 769          */
 770         result = sigaction(SIGIO, &act, NULL);
 771         if(result == -1) {
 772                 PERROR("sigaction");
 773                 return -1;
 774         }
 775
 776         return 0;
 777 }
 778
 779 static void auto_probe_connect(struct marker *m)
 780 {
 781         int result;
 782
 783         result = ltt_marker_connect(m->channel, m->name, "default");
 784         if(result)
 785                 ERR("ltt_marker_connect");
 786
 787         DBG("just auto connected marker %s %s to probe default", m->channel, m->name);
 788 }
 789
 790 static void __attribute__((constructor(101))) init0()
 791 {
 792         DBG("UST_AUTOPROBE constructor");
 793         if(getenv("UST_AUTOPROBE")) {
 794                 marker_set_new_marker_cb(auto_probe_connect);
 795         }
 796 }
 797
 798 static void fini(void);
 799
 800 static void __attribute__((constructor(1000))) init()
 801 {
 802         int result;
 803
 804         DBG("UST_TRACE constructor");
 805
 806         /* Must create socket before signal handler to prevent races.
 807          */
 808         result = init_socket();
 809         if(result == -1) {
 810                 ERR("init_socket error");
 811                 return;
 812         }
 813         result = init_signal_handler();
 814         if(result == -1) {
 815                 ERR("init_signal_handler error");
 816                 return;
 817         }
 818
 819         if(getenv("UST_TRACE")) {
 820                 char trace_name[] = "auto";
 821                 char trace_type[] = "ustrelay";
 822
 823                 DBG("starting early tracing");
 824
 825                 /* Ensure marker control is initialized */
 826                 init_marker_control();
 827
 828                 /* Ensure relay is initialized */
 829                 init_ustrelay_transport();
 830
 831                 /* Ensure markers are initialized */
 832                 init_markers();
 833
 834                 /* In case. */
 835                 ltt_channels_register("ust");
 836
 837                 result = ltt_trace_setup(trace_name);
 838                 if(result < 0) {
 839                         ERR("ltt_trace_setup failed");
 840                         return;
 841                 }
 842
 843                 result = ltt_trace_set_type(trace_name, trace_type);
 844                 if(result < 0) {
 845                         ERR("ltt_trace_set_type failed");
 846                         return;
 847                 }
 848
 849                 result = ltt_trace_alloc(trace_name);
 850                 if(result < 0) {
 851                         ERR("ltt_trace_alloc failed");
 852                         return;
 853                 }
 854
 855                 result = ltt_trace_start(trace_name);
 856                 if(result < 0) {
 857                         ERR("ltt_trace_start failed");
 858                         return;
 859                 }
 860                 inform_consumer_daemon();
 861         }
 862
 863
 864         return;
 865
 866         /* should decrementally destroy stuff if error */
 867
 868 }
 869
 870 /* This is only called if we terminate normally, not with an unhandled signal,
 871  * so we cannot rely on it. */
 872
 873 static void __attribute__((destructor)) fini()
 874 {
 875         int result;
 876
 877         /* if trace running, finish it */
 878
 879         DBG("destructor stopping traces");
 880
 881         result = ltt_trace_stop("auto");
 882         if(result == -1) {
 883                 ERR("ltt_trace_stop error");
 884         }
 885
 886         result = ltt_trace_destroy("auto");
 887         if(result == -1) {
 888                 ERR("ltt_trace_destroy error");
 889         }
 890
 891         /* FIXME: wait for the consumer to be done */
 892         //DBG("waiting 5 sec for consume");
 893         //sleep(5);
 894
 895         destroy_socket();
 896 }