src/bin/lttng/commands/destroy.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 modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <popt.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <stdbool.h>
  27 #include <lttng/lttng.h>
  28
  29 #include "../command.h"
  30
  31 #include <common/mi-lttng.h>
  32 #include <common/sessiond-comm/sessiond-comm.h>
  33 #include <common/utils.h>
  34
  35 static char *opt_session_name;
  36 static int opt_destroy_all;
  37 static int opt_no_wait;
  38
  39 #ifdef LTTNG_EMBED_HELP
  40 static const char help_msg[] =
  41 #include <lttng-destroy.1.h>
  42 ;
  43 #endif
  44
  45 /* Mi writer */
  46 static struct mi_writer *writer;
  47
  48 enum {
  49         OPT_HELP = 1,
  50         OPT_LIST_OPTIONS,
  51 };
  52
  53 static struct poptOption long_options[] = {
  54         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  55         {"help",      'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  56         {"all",       'a', POPT_ARG_VAL, &opt_destroy_all, 1, 0, 0},
  57         {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  58         {"no-wait",   'n', POPT_ARG_VAL, &opt_no_wait, 1, 0, 0},
  59         {0, 0, 0, 0, 0, 0, 0}
  60 };
  61
  62 /*
  63  * destroy_session
  64  *
  65  * Unregister the provided session to the session daemon. On success, removes
  66  * the default configuration.
  67  */
  68 static int destroy_session(struct lttng_session *session)
  69 {
  70         int ret;
  71         char *session_name = NULL;
  72         bool session_was_already_stopped;
  73         enum lttng_error_code ret_code;
  74         struct lttng_destruction_handle *handle = NULL;
  75         enum lttng_destruction_handle_status status;
  76         bool newline_needed = false, printed_destroy_msg = false;
  77         enum lttng_rotation_state rotation_state;
  78         char *stats_str = NULL;
  79
  80         ret = lttng_stop_tracing_no_wait(session->name);
  81         if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
  82                 ERR("%s", lttng_strerror(ret));
  83         }
  84
  85         session_was_already_stopped = ret == -LTTNG_ERR_TRACE_ALREADY_STOPPED;
  86         if (!opt_no_wait) {
  87                 do {
  88                         ret = lttng_data_pending(session->name);
  89                         if (ret < 0) {
  90                                 /* Return the data available call error. */
  91                                 goto error;
  92                         }
  93
  94                         /*
  95                          * Data sleep time before retrying (in usec). Don't
  96                          * sleep if the call returned value indicates
  97                          * availability.
  98                          */
  99                         if (ret) {
 100                                 if (!printed_destroy_msg) {
 101                                         _MSG("Destroying session %s",
 102                                                         session->name);
 103                                         newline_needed = true;
 104                                         printed_destroy_msg = true;
 105                                         fflush(stdout);
 106                                 }
 107
 108                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
 109                                 _MSG(".");
 110                                 fflush(stdout);
 111                         }
 112                 } while (ret != 0);
 113         }
 114
 115         if (!session_was_already_stopped) {
 116                 /*
 117                  * Don't print the event and packet loss warnings since the user
 118                  * already saw them when stopping the trace.
 119                  */
 120                 ret = get_session_stats_str(session->name, &stats_str);
 121                 if (ret < 0) {
 122                         goto error;
 123                 }
 124         }
 125
 126         ret_code = lttng_destroy_session_ext(session->name, &handle);
 127         if (ret_code != LTTNG_OK) {
 128                 ret = -ret_code;
 129                 goto error;
 130         }
 131
 132         if (opt_no_wait) {
 133                 goto skip_wait_rotation;
 134         }
 135
 136         do {
 137                 status = lttng_destruction_handle_wait_for_completion(
 138                                 handle, DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US /
 139                                                         USEC_PER_MSEC);
 140                 switch (status) {
 141                 case LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT:
 142                         if (!printed_destroy_msg) {
 143                                 _MSG("Destroying session %s", session->name);
 144                                 newline_needed = true;
 145                                 printed_destroy_msg = true;
 146                         }
 147                         _MSG(".");
 148                         fflush(stdout);
 149                         break;
 150                 case LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED:
 151                         break;
 152                 default:
 153                         ERR("%sFailed to wait for the completion of the destruction of session \"%s\"",
 154                                         newline_needed ? "\n" : "",
 155                                         session->name);
 156                         newline_needed = false;
 157                         ret = -1;
 158                         goto error;
 159                 }
 160         } while (status == LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT);
 161
 162         status = lttng_destruction_handle_get_result(handle, &ret_code);
 163         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 164                 ERR("%sFailed to get the result of session destruction",
 165                                 newline_needed ? "\n" : "");
 166                 ret = -1;
 167                 newline_needed = false;
 168                 goto error;
 169         }
 170         if (ret_code != LTTNG_OK) {
 171                 ret = -ret_code;
 172                 goto error;
 173         }
 174
 175         status = lttng_destruction_handle_get_rotation_state(
 176                         handle, &rotation_state);
 177         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 178                 ERR("%sFailed to get rotation state from destruction handle",
 179                                 newline_needed ? "\n" : "");
 180                 newline_needed = false;
 181                 goto skip_wait_rotation;
 182         }
 183
 184         switch (rotation_state) {
 185         case LTTNG_ROTATION_STATE_NO_ROTATION:
 186                 break;
 187         case LTTNG_ROTATION_STATE_COMPLETED:
 188         {
 189                 const struct lttng_trace_archive_location *location;
 190
 191                 status = lttng_destruction_handle_get_archive_location(
 192                                 handle, &location);
 193                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 194                         ret = print_trace_archive_location(
 195                                         location, session->name);
 196                         if (ret) {
 197                                 ERR("%sFailed to print the location of trace archive",
 198                                                 newline_needed ? "\n" : "");
 199                                 newline_needed = false;
 200                                 goto skip_wait_rotation;
 201                         }
 202                         break;
 203                 }
 204                 /* fall-through. */
 205         }
 206         default:
 207                 ERR("%sFailed to get the location of the rotation performed during the session's destruction",
 208                                 newline_needed ? "\n" : "");
 209                 newline_needed = false;
 210                 goto skip_wait_rotation;
 211         }
 212 skip_wait_rotation:
 213         MSG("%sSession %s destroyed", newline_needed ? "\n" : "",
 214                         session->name);
 215         newline_needed = false;
 216         if (stats_str) {
 217                 MSG("%s", stats_str);
 218         }
 219
 220         session_name = get_session_name_quiet();
 221         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 222                 config_destroy_default();
 223         }
 224
 225         if (lttng_opt_mi) {
 226                 ret = mi_lttng_session(writer, session, 0);
 227                 if (ret) {
 228                         ret = CMD_ERROR;
 229                         goto error;
 230                 }
 231         }
 232
 233         ret = CMD_SUCCESS;
 234 error:
 235         if (newline_needed) {
 236                 MSG("");
 237         }
 238         lttng_destruction_handle_destroy(handle);
 239         free(session_name);
 240         free(stats_str);
 241         return ret;
 242 }
 243
 244 /*
 245  * destroy_all_sessions
 246  *
 247  * Call destroy_sessions for each registered sessions
 248  */
 249 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 250 {
 251         int i;
 252         bool error_occurred = false;
 253
 254         assert(count >= 0);
 255         if (count == 0) {
 256                 MSG("No session found, nothing to do.");
 257         }
 258
 259         for (i = 0; i < count; i++) {
 260                 int ret = destroy_session(&sessions[i]);
 261
 262                 if (ret < 0) {
 263                         ERR("%s during the destruction of session \"%s\"",
 264                                         lttng_strerror(ret),
 265                                         sessions[i].name);
 266                         /* Continue to next session. */
 267                         error_occurred = true;
 268                 }
 269         }
 270
 271         return error_occurred ? CMD_ERROR : CMD_SUCCESS;
 272 }
 273
 274 /*
 275  * The 'destroy <options>' first level command
 276  */
 277 int cmd_destroy(int argc, const char **argv)
 278 {
 279         int opt;
 280         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 281         static poptContext pc;
 282         char *session_name = NULL;
 283         const char *leftover = NULL;
 284
 285         struct lttng_session *sessions;
 286         int count;
 287         int found;
 288
 289         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 290         poptReadDefaultConfig(pc, 0);
 291
 292         while ((opt = poptGetNextOpt(pc)) != -1) {
 293                 switch (opt) {
 294                 case OPT_HELP:
 295                         SHOW_HELP();
 296                         break;
 297                 case OPT_LIST_OPTIONS:
 298                         list_cmd_options(stdout, long_options);
 299                         break;
 300                 default:
 301                         ret = CMD_UNDEFINED;
 302                         break;
 303                 }
 304                 goto end;
 305         }
 306
 307         /* Mi preparation */
 308         if (lttng_opt_mi) {
 309                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 310                 if (!writer) {
 311                         ret = -LTTNG_ERR_NOMEM;
 312                         goto end;
 313                 }
 314
 315                 /* Open command element */
 316                 ret = mi_lttng_writer_command_open(writer,
 317                                 mi_lttng_element_command_destroy);
 318                 if (ret) {
 319                         ret = CMD_ERROR;
 320                         goto end;
 321                 }
 322
 323                 /* Open output element */
 324                 ret = mi_lttng_writer_open_element(writer,
 325                                 mi_lttng_element_command_output);
 326                 if (ret) {
 327                         ret = CMD_ERROR;
 328                         goto end;
 329                 }
 330
 331                 /* For validation and semantic purpose we open a sessions element */
 332                 ret = mi_lttng_sessions_open(writer);
 333                 if (ret) {
 334                         ret = CMD_ERROR;
 335                         goto end;
 336                 }
 337         }
 338
 339         /* Recuperate all sessions for further operation */
 340         count = lttng_list_sessions(&sessions);
 341         if (count < 0) {
 342                 ERR("%s", lttng_strerror(count));
 343                 command_ret = CMD_ERROR;
 344                 success = 0;
 345                 goto mi_closing;
 346         }
 347
 348         /* Ignore session name in case all sessions are to be destroyed */
 349         if (opt_destroy_all) {
 350                 command_ret = destroy_all_sessions(sessions, count);
 351                 if (command_ret) {
 352                         success = 0;
 353                 }
 354         } else {
 355                 opt_session_name = (char *) poptGetArg(pc);
 356
 357                 if (!opt_session_name) {
 358                         /* No session name specified, lookup default */
 359                         session_name = get_session_name();
 360                         if (session_name == NULL) {
 361                                 command_ret = CMD_ERROR;
 362                                 success = 0;
 363                                 goto mi_closing;
 364                         }
 365                 } else {
 366                         session_name = opt_session_name;
 367                 }
 368
 369                 /* Find the corresponding lttng_session struct */
 370                 found = 0;
 371                 for (i = 0; i < count; i++) {
 372                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 373                                 found = 1;
 374                                 command_ret = destroy_session(&sessions[i]);
 375                                 if (command_ret) {
 376                                         success = 0;
 377                                         ERR("%s during the destruction of session \"%s\"",
 378                                                         lttng_strerror(command_ret),
 379                                                         sessions[i].name);
 380                                 }
 381                         }
 382                 }
 383
 384                 if (!found) {
 385                         ERR("Session name %s not found", session_name);
 386                         command_ret = LTTNG_ERR_SESS_NOT_FOUND;
 387                         success = 0;
 388                         goto mi_closing;
 389                 }
 390         }
 391
 392         leftover = poptGetArg(pc);
 393         if (leftover) {
 394                 ERR("Unknown argument: %s", leftover);
 395                 ret = CMD_ERROR;
 396                 success = 0;
 397                 goto mi_closing;
 398         }
 399
 400 mi_closing:
 401         /* Mi closing */
 402         if (lttng_opt_mi) {
 403                 /* Close sessions and output element element */
 404                 ret = mi_lttng_close_multi_element(writer, 2);
 405                 if (ret) {
 406                         ret = CMD_ERROR;
 407                         goto end;
 408                 }
 409
 410                 /* Success ? */
 411                 ret = mi_lttng_writer_write_element_bool(writer,
 412                                 mi_lttng_element_command_success, success);
 413                 if (ret) {
 414                         ret = CMD_ERROR;
 415                         goto end;
 416                 }
 417
 418                 /* Command element close */
 419                 ret = mi_lttng_writer_command_close(writer);
 420                 if (ret) {
 421                         ret = CMD_ERROR;
 422                         goto end;
 423                 }
 424         }
 425 end:
 426         /* Mi clean-up */
 427         if (writer && mi_lttng_writer_destroy(writer)) {
 428                 /* Preserve original error code */
 429                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 430         }
 431
 432         if (opt_session_name == NULL) {
 433                 free(session_name);
 434         }
 435
 436         /* Overwrite ret if an error occurred during destroy_session/all */
 437         ret = command_ret ? command_ret : ret;
 438
 439         poptFreeContext(pc);
 440         return ret;
 441 }