ltt-sessiond/ltt-sessiond.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <fcntl.h>
  21 #include <getopt.h>
  22 #include <grp.h>
  23 #include <limits.h>
  24 #include <pthread.h>
  25 #include <signal.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/ipc.h>
  30 #include <sys/shm.h>
  31 #include <sys/socket.h>
  32 #include <sys/stat.h>
  33 #include <sys/types.h>
  34 #include <unistd.h>
  35
  36 #include <urcu/list.h>          /* URCU list library (-lurcu) */
  37 #include <ust/ustctl.h>         /* UST control lib (-lust) */
  38 #include <lttng/liblttngctl.h>
  39
  40 #include "liblttsessiondcomm.h"
  41 #include "ltt-sessiond.h"
  42 #include "lttngerr.h"
  43
  44 /* Const values */
  45 const char default_home_dir[] = DEFAULT_HOME_DIR;
  46 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
  47 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
  48 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
  49
  50 /* Static functions */
  51 static int set_signal_handler(void);
  52 static int set_socket_perms(void);
  53 static void sighandler(int sig);
  54 static void cleanup(void);
  55 static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm);
  56 static int check_existing_daemon(void);
  57 static int notify_apps(const char* name);
  58 static int connect_app(pid_t pid);
  59 static int init_daemon_socket(void);
  60 static int process_client_msg(int sock, struct lttcomm_session_msg*);
  61 static int send_unix_sock(int sock, void *buf, size_t len);
  62 static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm);
  63
  64 /* Command function */
  65 static void get_list_apps(pid_t *pids);
  66 static void get_list_sessions(struct lttng_session *lt);
  67
  68 static void *thread_manage_clients(void *data);
  69 static void *thread_manage_apps(void *data);
  70
  71 static int create_session(char *name, uuid_t *session_id);
  72 static int destroy_session(uuid_t *uuid);
  73
  74 static struct ltt_session *find_session_by_uuid(uuid_t session_id);
  75 static struct ltt_session *find_session_by_name(char *name);
  76
  77 /* Variables */
  78 const char *progname;
  79 const char *opt_tracing_group;
  80 static int opt_sig_parent;
  81 static int opt_daemon;
  82 int opt_verbose;
  83 int opt_quiet;
  84 static int is_root;                     /* Set to 1 if the daemon is running as root */
  85 static pid_t ppid;
  86
  87 static char apps_unix_sock_path[PATH_MAX];                      /* Global application Unix socket path */
  88 static char client_unix_sock_path[PATH_MAX];            /* Global client Unix socket path */
  89
  90 static int client_socket;
  91 static int apps_socket;
  92
  93 static struct ltt_session *current_session;
  94
  95 /* Number of element for the list below. */
  96 static unsigned int session_count;
  97 static unsigned int traceable_app_count;
  98
  99 /* Init session's list */
 100 static struct ltt_session_list ltt_session_list = {
 101         .head = CDS_LIST_HEAD_INIT(ltt_session_list.head),
 102 };
 103
 104 /* Init ust traceabl application's list */
 105 static struct ltt_traceable_app_list ltt_traceable_app_list = {
 106         .head = CDS_LIST_HEAD_INIT(ltt_traceable_app_list.head),
 107 };
 108
 109 /*
 110  *      thread_manage_apps
 111  *
 112  *      This thread manage the application socket communication
 113  */
 114 static void *thread_manage_apps(void *data)
 115 {
 116         int sock, ret;
 117         struct ltt_traceable_app *lta;
 118
 119         /* TODO: Something more elegant is needed but fine for now */
 120         struct {
 121                 int reg;        /* 1:register, 0:unregister */
 122                 pid_t pid;
 123                 uid_t uid;
 124         } reg_msg;
 125
 126         /* Notify all applications to register */
 127         notify_apps(default_global_apps_pipe);
 128
 129         ret = lttcomm_listen_unix_sock(apps_socket);
 130         if (ret < 0) {
 131                 goto error;
 132         }
 133
 134         while (1) {
 135                 /* Blocking call, waiting for transmission */
 136                 sock = lttcomm_accept_unix_sock(apps_socket);
 137                 if (sock < 0) {
 138                         goto error;
 139                 }
 140
 141                 /* Basic recv here to handle the very simple data
 142                  * that the libust send to register (reg_msg).
 143                  */
 144                 ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
 145                 if (ret < 0) {
 146                         perror("recv");
 147                         continue;
 148                 }
 149
 150                 /* Add application to the global traceable list */
 151                 if (reg_msg.reg == 1) {
 152                         /* Registering */
 153                         lta = malloc(sizeof(struct ltt_traceable_app));
 154                         lta->pid = reg_msg.pid;
 155                         lta->uid = reg_msg.uid;
 156                         cds_list_add(&lta->list, &ltt_traceable_app_list.head);
 157                         traceable_app_count++;
 158                 } else {
 159                         /* Unregistering */
 160                         lta = NULL;
 161                         cds_list_for_each_entry(lta, &ltt_traceable_app_list.head, list) {
 162                                 if (lta->pid == reg_msg.pid && lta->uid == reg_msg.uid) {
 163                                         cds_list_del(&lta->list);
 164                                         /* Check to not overflow here */
 165                                         if (traceable_app_count != 0) {
 166                                                 traceable_app_count--;
 167                                         }
 168                                         break;
 169                                 }
 170                         }
 171
 172                         /* If an item was found, free it from memory */
 173                         if (lta) {
 174                                 free(lta);
 175                         }
 176                 }
 177         }
 178
 179 error:
 180
 181         return NULL;
 182 }
 183
 184 /*
 185  *      thread_manage_clients
 186  *
 187  *      This thread manage all clients request using the unix
 188  *      client socket for communication.
 189  */
 190 static void *thread_manage_clients(void *data)
 191 {
 192         int sock, ret;
 193         struct lttcomm_session_msg lsm;
 194
 195         ret = lttcomm_listen_unix_sock(client_socket);
 196         if (ret < 0) {
 197                 goto error;
 198         }
 199
 200         /* Notify parent pid that we are ready
 201          * to accept command for client side.
 202          */
 203         if (opt_sig_parent) {
 204                 kill(ppid, SIGCHLD);
 205         }
 206
 207         while (1) {
 208                 /* Blocking call, waiting for transmission */
 209                 sock = lttcomm_accept_unix_sock(client_socket);
 210                 if (sock < 0) {
 211                         goto error;
 212                 }
 213
 214                 /*
 215                  * Data is received from the lttng client. The struct
 216                  * lttcomm_session_msg (lsm) contains the command and data
 217                  * request of the client.
 218                  */
 219                 ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm));
 220                 if (ret <= 0) {
 221                         continue;
 222                 }
 223
 224                 /* This function dispatch the work to the LTTng or UST libs
 225                  * and then sends back the response to the client. This is needed
 226                  * because there might be more then one lttcomm_lttng_msg to
 227                  * send out so process_client_msg do both jobs.
 228                  */
 229                 ret = process_client_msg(sock, &lsm);
 230                 if (ret < 0) {
 231                         /* Error detected but still accept command */
 232                         continue;
 233                 }
 234         }
 235
 236 error:
 237         return NULL;
 238 }
 239
 240 /*
 241  *  send_unix_sock
 242  *
 243  *  Send data on a unix socket using the liblttsessiondcomm API.
 244  *
 245  *  Return lttcomm error code.
 246  */
 247 static int send_unix_sock(int sock, void *buf, size_t len)
 248 {
 249         /* Check valid length */
 250         if (len <= 0) {
 251                 return -1;
 252         }
 253
 254         return lttcomm_send_unix_sock(sock, buf, len);
 255 }
 256
 257 /*
 258  *      connect_app
 259  *
 260  *      Return a socket connected to the libust communication socket
 261  *      of the application identified by the pid.
 262  */
 263 static int connect_app(pid_t pid)
 264 {
 265         int sock;
 266
 267         sock = ustctl_connect_pid(pid);
 268         if (sock < 0) {
 269                 ERR("Fail connecting to the PID %d\n", pid);
 270         }
 271
 272         return sock;
 273 }
 274
 275 /*
 276  *      notify_apps
 277  *
 278  *  Notify apps by writing 42 to a named pipe using name.
 279  *      Every applications waiting for a ltt-sessiond will be notified
 280  *      and re-register automatically to the session daemon.
 281  *
 282  *      Return open or write error value.
 283  */
 284 static int notify_apps(const char *name)
 285 {
 286         int fd;
 287         int ret = -1;
 288
 289         /* Try opening the global pipe */
 290         fd = open(name, O_WRONLY);
 291         if (fd < 0) {
 292                 goto error;
 293         }
 294
 295         /* Notify by writing on the pipe */
 296         ret = write(fd, "42", 2);
 297         if (ret < 0) {
 298                 perror("write");
 299         }
 300
 301 error:
 302         return ret;
 303 }
 304
 305 /*
 306  *      find_session_by_uuid
 307  *
 308  *      Return a ltt_session structure ptr that matches the uuid.
 309  */
 310 static struct ltt_session *find_session_by_uuid(uuid_t session_id)
 311 {
 312         int found = 0;
 313         struct ltt_session *iter;
 314
 315         /* Sanity check for NULL session_id */
 316         if (uuid_is_null(session_id)) {
 317                 goto end;
 318         }
 319
 320         cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
 321                 if (uuid_compare(iter->uuid, session_id) == 0) {
 322                         found = 1;
 323                         break;
 324                 }
 325         }
 326
 327 end:
 328         if (!found) {
 329                 iter = NULL;
 330         }
 331         return iter;
 332 }
 333
 334 /*
 335  *      find_session_by_name
 336  *
 337  *      Return a ltt_session structure ptr that matches name.
 338  *      If no session found, NULL is returned.
 339  */
 340 static struct ltt_session *find_session_by_name(char *name)
 341 {
 342         int found = 0;
 343         struct ltt_session *iter;
 344
 345         cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
 346                 if (strncmp(iter->name, name, strlen(iter->name)) == 0) {
 347                         found = 1;
 348                         break;
 349                 }
 350         }
 351
 352         if (!found) {
 353                 iter = NULL;
 354         }
 355
 356         return iter;
 357 }
 358
 359 /*
 360  *      destroy_session
 361  *
 362  *  Delete session from the global session list
 363  *  and free the memory.
 364  *
 365  *  Return -1 if no session is found.
 366  *  On success, return 1;
 367  */
 368 static int destroy_session(uuid_t *uuid)
 369 {
 370         int found = -1;
 371         struct ltt_session *iter;
 372
 373         cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
 374                 if (uuid_compare(iter->uuid, *uuid) == 0) {
 375                         cds_list_del(&iter->list);
 376                         free(iter);
 377                         session_count--;
 378                         found = 1;
 379                         break;
 380                 }
 381         }
 382
 383         return found;
 384 }
 385
 386 /*
 387  *      create_session
 388  *
 389  *      Create a brand new session and add it to the
 390  *      global session list.
 391  */
 392 static int create_session(char *name, uuid_t *session_id)
 393 {
 394         struct ltt_session *new_session;
 395
 396         /* Allocate session data structure */
 397         new_session = malloc(sizeof(struct ltt_session));
 398         if (new_session == NULL) {
 399                 perror("malloc");
 400                 goto error;
 401         }
 402
 403         if (name != NULL) {
 404                 if (asprintf(&new_session->name, "%s", name) < 0) {
 405                         goto error;
 406                 }
 407         } else {
 408                 /* Generate session name based on the session count */
 409                 if (asprintf(&new_session->name, "%s%d", "lttng-", session_count) < 0) {
 410                         goto error;
 411                 }
 412         }
 413
 414         /* UUID generation */
 415         uuid_generate(new_session->uuid);
 416         uuid_copy(*session_id, new_session->uuid);
 417
 418         /* Set consumer (identifier) to 0. This means that there is
 419          * NO consumer attach to that session yet.
 420          */
 421         new_session->ust_consumer = 0;
 422         new_session->lttng_consumer = 0;
 423
 424         /* Init list */
 425         CDS_INIT_LIST_HEAD(&new_session->ust_traces);
 426         CDS_INIT_LIST_HEAD(&new_session->lttng_traces);
 427
 428         /* Add new session to the global session list */
 429         cds_list_add(&new_session->list, &ltt_session_list.head);
 430
 431         session_count++;
 432
 433         return 0;
 434
 435 error:
 436         return -1;
 437 }
 438
 439 /*
 440  *      get_list_apps
 441  *
 442  *  List traceable user-space application and fill an
 443  *  array of pids.
 444  */
 445 static void get_list_apps(pid_t *pids)
 446 {
 447         int i = 0;
 448         struct ltt_traceable_app *iter;
 449
 450         /* TODO: Mutex needed to access this list */
 451         cds_list_for_each_entry(iter, &ltt_traceable_app_list.head, list) {
 452                 pids[i] = iter->pid;
 453                 i++;
 454         }
 455 }
 456
 457 /*
 458  *  get_list_sessions
 459  *
 460  *  List sessions and fill the data buffer.
 461  */
 462 static void get_list_sessions(struct lttng_session *lt)
 463 {
 464         int i = 0;
 465         struct ltt_session *iter;
 466         struct lttng_session lsess;
 467
 468         /* Iterate over session list and append data after
 469          * the control struct in the buffer.
 470          */
 471         cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
 472                 /* Copy name and uuid */
 473                 uuid_unparse(iter->uuid, lsess.uuid);
 474                 strncpy(lsess.name, iter->name, sizeof(lsess.name));
 475                 lsess.name[sizeof(lsess.name) - 1] = '\0';
 476                 memcpy(&lt[i], &lsess, sizeof(lsess));
 477                 i++;
 478                 /* Reset struct for next pass */
 479                 memset(&lsess, 0, sizeof(lsess));
 480         }
 481 }
 482
 483 /*
 484  *  copy_common_data
 485  *
 486  *  Copy common data between lttcomm_lttng_msg and lttcomm_session_msg
 487  */
 488 static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm)
 489 {
 490         llm->cmd_type = lsm->cmd_type;
 491         llm->pid = lsm->pid;
 492
 493         /* Manage uuid */
 494         if (!uuid_is_null(lsm->session_id)) {
 495                 uuid_copy(llm->session_id, lsm->session_id);
 496         }
 497
 498         strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name));
 499         llm->trace_name[strlen(llm->trace_name) - 1] = '\0';
 500 }
 501
 502 /*
 503  *  setup_data_buffer
 504  *
 505  *  Setup the outgoing data buffer for the response
 506  *  data allocating the right amount of memory.
 507  *
 508  *  Return total size of the buffer pointed by buf.
 509  */
 510 static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm)
 511 {
 512         int ret = 0;
 513         size_t buf_size;
 514
 515         buf_size = sizeof(struct lttcomm_lttng_msg) + s_data;
 516         *buf = malloc(buf_size);
 517         if (*buf == NULL) {
 518                 perror("malloc");
 519                 ret = -1;
 520                 goto error;
 521         }
 522
 523         /* Setup lttcomm_lttng_msg data and copy
 524          * it to the newly allocated buffer.
 525          */
 526         llm->size_payload = s_data;
 527         memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg));
 528
 529         return buf_size;
 530
 531 error:
 532         return ret;
 533 }
 534
 535 /*
 536  *      process_client_msg
 537  *
 538  *      This takes the lttcomm_session_msg struct and process the command requested
 539  *      by the client. It then creates response(s) and send it back to the
 540  *      given socket (sock).
 541  *
 542  *      Return any error encountered or 0 for success.
 543  */
 544 static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
 545 {
 546         int ret;
 547         int buf_size;
 548         char *send_buf = NULL;
 549         struct lttcomm_lttng_msg llm;
 550
 551         /* Copy common data to identify the response
 552          * on the lttng client side.
 553          */
 554         copy_common_data(&llm, lsm);
 555
 556         /* Default return code.
 557          * In our world, everything is OK... right? ;)
 558          */
 559         llm.ret_code = LTTCOMM_OK;
 560
 561         /* Process by command type */
 562         switch (lsm->cmd_type) {
 563                 case LTTNG_CREATE_SESSION:
 564                 {
 565                         ret = create_session(lsm->session_name, &llm.session_id);
 566                         if (ret < 0) {
 567                                 goto end;
 568                         }
 569
 570                         buf_size = setup_data_buffer(&send_buf, 0, &llm);
 571                         if (buf_size < 0) {
 572                                 ret = LTTCOMM_FATAL;
 573                                 goto end;
 574                         }
 575
 576                         break;
 577                 }
 578                 case LTTNG_DESTROY_SESSION:
 579                 {
 580                         ret = destroy_session(&lsm->session_id);
 581                         if (ret < 0) {
 582                                 ret = LTTCOMM_NO_SESS;
 583                         } else {
 584                                 ret = LTTCOMM_OK;
 585                         }
 586
 587                         /* No auxiliary data so only send the llm struct. */
 588                         goto end;
 589                 }
 590                 case UST_CREATE_TRACE:
 591                 {
 592                         int sock;
 593                         sock = connect_app(lsm->pid);
 594
 595                         ret = ustctl_create_trace(sock, "auto");
 596                         if (ret < 0) {
 597                                 ret = LTTCOMM_CREATE_FAIL;
 598                         } else {
 599                                 ret = LTTCOMM_OK;
 600                         }
 601
 602                         goto end;
 603                 }
 604                 case UST_LIST_APPS:
 605                 {
 606                         /* Stop right now if no apps */
 607                         if (traceable_app_count == 0) {
 608                                 ret = LTTCOMM_NO_APPS;
 609                                 goto end;
 610                         }
 611
 612                         /* Setup data buffer and details for transmission */
 613                         buf_size = setup_data_buffer(&send_buf,
 614                                         sizeof(pid_t) * traceable_app_count, &llm);
 615                         if (buf_size < 0) {
 616                                 ret = LTTCOMM_FATAL;
 617                                 goto end;
 618                         }
 619
 620                         get_list_apps((pid_t *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 621
 622                         break;
 623                 }
 624                 case LTTNG_LIST_SESSIONS:
 625                 {
 626                         /* Stop right now if no session */
 627                         if (session_count == 0) {
 628                                 ret = LTTCOMM_NO_SESS;
 629                                 goto end;
 630                         }
 631
 632                         /* Setup data buffer and details for transmission */
 633                         buf_size = setup_data_buffer(&send_buf,
 634                                         (sizeof(struct lttng_session) * session_count), &llm);
 635                         if (buf_size < 0) {
 636                                 ret = LTTCOMM_FATAL;
 637                                 goto end;
 638                         }
 639
 640                         get_list_sessions((struct lttng_session *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 641
 642                         break;
 643                 }
 644                 default:
 645                 {
 646                         /* Undefined command */
 647                         ret = LTTCOMM_UND;
 648                         goto end;
 649                 }
 650         }
 651
 652         ret = send_unix_sock(sock, send_buf, buf_size);
 653
 654         if (send_buf != NULL) {
 655                 free(send_buf);
 656         }
 657
 658         return ret;
 659
 660 end:
 661         /* Notify client of error */
 662         llm.ret_code = ret;
 663         llm.size_payload = 0;
 664         send_unix_sock(sock, (void*) &llm, sizeof(llm));
 665
 666         return ret;
 667 }
 668
 669 /*
 670  * usage function on stderr
 671  */
 672 static void usage(void)
 673 {
 674         fprintf(stderr, "Usage:\n%s OPTIONS\n\nOptions:\n"
 675                         "\t-h, --help\t\tDisplay this usage.\n"
 676                         "\t-c, --client-sock PATH\t\tSpecify path for the client unix socket\n"
 677                         "\t-a, --apps-sock PATH\t\tSpecify path for apps unix socket.\n"
 678                         "\t-d, --daemonize\t\tStart as a daemon.\n"
 679                         "\t-g, --group NAME\t\tSpecify the tracing group name. (default: tracing)\n"
 680                         "\t-V, --version\t\tShow version number.\n"
 681                         "\t-S, --sig-parent\t\tSend SIGCHLD to parent pid to notify readiness.\n"
 682                         "\t-q, --quiet\t\tNo output at all.\n",
 683                         progname);
 684 }
 685
 686 /*
 687  * daemon argument parsing
 688  */
 689 static int parse_args(int argc, char **argv)
 690 {
 691         int c;
 692
 693         static struct option long_options[] = {
 694                 { "client-sock", 1, 0, 'c' },
 695                 { "apps-sock", 1, 0, 'a' },
 696                 { "daemonize", 0, 0, 'd' },
 697                 { "sig-parent", 0, 0, 'S' },
 698                 { "help", 0, 0, 'h' },
 699                 { "group", 1, 0, 'g' },
 700                 { "version", 0, 0, 'V' },
 701                 { "quiet", 0, 0, 'q' },
 702                 { NULL, 0, 0, 0 }
 703         };
 704
 705         while (1) {
 706                 int option_index = 0;
 707                 c = getopt_long(argc, argv, "dhqVS" "a:c:g:s:", long_options, &option_index);
 708                 if (c == -1) {
 709                         break;
 710                 }
 711
 712                 switch (c) {
 713                 case 0:
 714                         fprintf(stderr, "option %s", long_options[option_index].name);
 715                         if (optarg) {
 716                                 fprintf(stderr, " with arg %s\n", optarg);
 717                         }
 718                         break;
 719                 case 's':
 720                         snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
 721                         break;
 722                 case 'a':
 723                         snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
 724                         break;
 725                 case 'd':
 726                         opt_daemon = 1;
 727                         break;
 728                 case 'g':
 729                         opt_tracing_group = strdup(optarg);
 730                         break;
 731                 case 'h':
 732                         usage();
 733                         exit(EXIT_FAILURE);
 734                 case 'V':
 735                         fprintf(stdout, "%s\n", VERSION);
 736                         exit(EXIT_SUCCESS);
 737                 case 'S':
 738                         opt_sig_parent = 1;
 739                         break;
 740                 case 'q':
 741                         opt_quiet = 1;
 742                         break;
 743                 default:
 744                         /* Unknown option or other error.
 745                          * Error is printed by getopt, just return */
 746                         return -1;
 747                 }
 748         }
 749
 750         return 0;
 751 }
 752
 753 /*
 754  *      init_daemon_socket
 755  *
 756  *      Creates the two needed socket by the daemon.
 757  *              apps_socket - The communication socket for all UST apps.
 758  *              client_socket - The communication of the cli tool (lttng).
 759  */
 760 static int init_daemon_socket()
 761 {
 762         int ret = 0;
 763         mode_t old_umask;
 764
 765         old_umask = umask(0);
 766
 767         /* Create client tool unix socket */
 768         client_socket = lttcomm_create_unix_sock(client_unix_sock_path);
 769         if (client_socket < 0) {
 770                 ret = -1;
 771                 goto end;
 772         }
 773
 774         /* File permission MUST be 660 */
 775         ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
 776         if (ret < 0) {
 777                 perror("chmod");
 778                 goto end;
 779         }
 780
 781         /* Create the application unix socket */
 782         apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path);
 783         if (apps_socket < 0) {
 784                 ret = -1;
 785                 goto end;
 786         }
 787
 788         /* File permission MUST be 660 */
 789         ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
 790         if (ret < 0) {
 791                 perror("chmod");
 792                 goto end;
 793         }
 794
 795 end:
 796         umask(old_umask);
 797         return ret;
 798 }
 799
 800 /*
 801  *      check_existing_daemon
 802  *
 803  *      Check if the global socket is available.
 804  *      If yes, error is returned.
 805  */
 806 static int check_existing_daemon()
 807 {
 808         int ret;
 809
 810         ret = access(client_unix_sock_path, F_OK);
 811         if (ret == 0) {
 812                 ret = access(apps_unix_sock_path, F_OK);
 813         }
 814
 815         return ret;
 816 }
 817
 818 /*
 819  *      get_home_dir
 820  *
 821  *      Return pointer to home directory path using
 822  *      the env variable HOME.
 823  *
 824  *      Default : /tmp
 825  */
 826 static const char *get_home_dir(void)
 827 {
 828         const char *home_path;
 829
 830         if ((home_path = (const char *) getenv("HOME")) == NULL) {
 831                 home_path = default_home_dir;
 832         }
 833
 834         return home_path;
 835 }
 836
 837 /*
 838  *  set_socket_perms
 839  *
 840  *      Set the tracing group gid onto the client socket.
 841  */
 842 static int set_socket_perms(void)
 843 {
 844         int ret;
 845         struct group *grp;
 846
 847         /* Decide which group name to use */
 848         (opt_tracing_group != NULL) ?
 849                 (grp = getgrnam(opt_tracing_group)) :
 850                 (grp = getgrnam(default_tracing_group));
 851
 852         if (grp == NULL) {
 853                 ERR("Missing tracing group. Aborting execution.\n");
 854                 ret = -1;
 855                 goto end;
 856         }
 857
 858         ret = chown(client_unix_sock_path, 0, grp->gr_gid);
 859         if (ret < 0) {
 860                 perror("chown");
 861         }
 862
 863 end:
 864         return ret;
 865 }
 866
 867 /*
 868  *      set_signal_handler
 869  *
 870  *      Setup signal handler for :
 871  *              SIGINT, SIGTERM, SIGPIPE
 872  */
 873 static int set_signal_handler(void)
 874 {
 875         int ret = 0;
 876         struct sigaction sa;
 877         sigset_t sigset;
 878
 879         if ((ret = sigemptyset(&sigset)) < 0) {
 880                 perror("sigemptyset");
 881                 return ret;
 882         }
 883
 884         sa.sa_handler = sighandler;
 885         sa.sa_mask = sigset;
 886         sa.sa_flags = 0;
 887         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 888                 perror("sigaction");
 889                 return ret;
 890         }
 891
 892         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 893                 perror("sigaction");
 894                 return ret;
 895         }
 896
 897         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 898                 perror("sigaction");
 899                 return ret;
 900         }
 901
 902         return ret;
 903 }
 904
 905 /**
 906  *      sighandler
 907  *
 908  *      Signal handler for the daemon
 909  */
 910 static void sighandler(int sig)
 911 {
 912         switch (sig) {
 913                 case SIGPIPE:
 914                         return;
 915                 case SIGINT:
 916                 case SIGTERM:
 917                         cleanup();
 918                         break;
 919                 default:
 920                         break;
 921         }
 922
 923         exit(EXIT_SUCCESS);
 924 }
 925
 926 /*
 927  *      cleanup
 928  *
 929  *      Cleanup the daemon on exit
 930  */
 931 static void cleanup()
 932 {
 933         /* <fun> */
 934         MSG("\n\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
 935         MSG("%c[%d;%dm Matthew, BEET driven development works!%c[%dm\n",27,1,33,27,0);
 936         /* </fun> */
 937
 938         unlink(client_unix_sock_path);
 939         unlink(apps_unix_sock_path);
 940 }
 941
 942 /*
 943  * main
 944  */
 945 int main(int argc, char **argv)
 946 {
 947         int i;
 948         int ret = 0;
 949         void *status;
 950         pthread_t threads[2];
 951
 952         /* Parse arguments */
 953         progname = argv[0];
 954         if ((ret = parse_args(argc, argv) < 0)) {
 955                 goto error;
 956         }
 957
 958         /* Daemonize */
 959         if (opt_daemon) {
 960                 ret = daemon(0, 0);
 961                 if (ret < 0) {
 962                         perror("daemon");
 963                         goto error;
 964                 }
 965         }
 966
 967         /* Check if daemon is UID = 0 */
 968         is_root = !getuid();
 969
 970         /* Set all sockets path */
 971         if (is_root) {
 972                 if (strlen(apps_unix_sock_path) == 0) {
 973                         (snprintf(apps_unix_sock_path, PATH_MAX,
 974                                         DEFAULT_GLOBAL_APPS_UNIX_SOCK));
 975                 }
 976
 977                 if (strlen(client_unix_sock_path) == 0) {
 978                         (snprintf(client_unix_sock_path, PATH_MAX,
 979                                         DEFAULT_GLOBAL_CLIENT_UNIX_SOCK));
 980                 }
 981         } else {
 982                 if (strlen(apps_unix_sock_path) == 0) {
 983                         (snprintf(apps_unix_sock_path, PATH_MAX,
 984                                         DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir()));
 985                 }
 986
 987                 /* Set the cli tool unix socket path */
 988                 if (strlen(client_unix_sock_path) == 0) {
 989                         (snprintf(client_unix_sock_path, PATH_MAX,
 990                                         DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir()));
 991                 }
 992         }
 993
 994         /* See if daemon already exist. If any of the two
 995          * socket needed by the daemon are present, this test fails
 996          */
 997         if ((ret = check_existing_daemon()) == 0) {
 998                 ERR("Already running daemon.\n");
 999                 goto error;
1000         }
1001
1002         if (set_signal_handler() < 0) {
1003                 goto error;
1004         }
1005
1006         /* Setup the two needed unix socket */
1007         if (init_daemon_socket() < 0) {
1008                 goto error;
1009         }
1010
1011         /* Set credentials to socket */
1012         if (is_root && (set_socket_perms() < 0)) {
1013                 goto error;
1014         }
1015
1016         /* Get parent pid if -S, --sig-parent is specified. */
1017         if (opt_sig_parent) {
1018                 ppid = getppid();
1019         }
1020
1021         while (1) {
1022                 /* Create thread to manage the client socket */
1023                 ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL);
1024                 if (ret != 0) {
1025                         perror("pthread_create");
1026                         goto error;
1027                 }
1028
1029                 /* Create thread to manage application socket */
1030                 ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL);
1031                 if (ret != 0) {
1032                         perror("pthread_create");
1033                         goto error;
1034                 }
1035
1036                 for (i = 0; i < 2; i++) {
1037                         ret = pthread_join(threads[i], &status);
1038                         if (ret != 0) {
1039                                 perror("pthread_join");
1040                                 goto error;
1041                         }
1042                 }
1043         }
1044
1045         cleanup();
1046         return 0;
1047
1048 error:
1049         cleanup();
1050
1051         return EXIT_FAILURE;
1052 }