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                                 _MSG("Destroying session %s", session->name);
 101                                 newline_needed = true;
 102                                 printed_destroy_msg = true;
 103                                 fflush(stdout);
 104
 105                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
 106                                 _MSG(".");
 107                                 fflush(stdout);
 108                         }
 109                 } while (ret != 0);
 110         }
 111
 112         if (!session_was_already_stopped) {
 113                 /*
 114                  * Don't print the event and packet loss warnings since the user
 115                  * already saw them when stopping the trace.
 116                  */
 117                 ret = get_session_stats_str(session->name, &stats_str);
 118                 if (ret < 0) {
 119                         goto error;
 120                 }
 121         }
 122
 123         ret_code = lttng_destroy_session_ext(session->name, &handle);
 124         if (ret_code != LTTNG_OK) {
 125                 ret = -ret_code;
 126                 goto error;
 127         }
 128
 129         if (opt_no_wait) {
 130                 goto skip_wait_rotation;
 131         }
 132
 133         do {
 134                 status = lttng_destruction_handle_wait_for_completion(
 135                                 handle, DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US /
 136                                                         USEC_PER_MSEC);
 137                 switch (status) {
 138                 case LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT:
 139                         if (!printed_destroy_msg) {
 140                                 _MSG("Destroying session %s", session->name);
 141                                 newline_needed = true;
 142                                 printed_destroy_msg = true;
 143                         }
 144                         _MSG(".");
 145                         fflush(stdout);
 146                         break;
 147                 case LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED:
 148                         break;
 149                 default:
 150                         ERR("%sFailed to wait for the completion of the destruction of session \"%s\"",
 151                                         newline_needed ? "\n" : "",
 152                                         session->name);
 153                         newline_needed = false;
 154                         ret = -1;
 155                         goto error;
 156                 }
 157         } while (status == LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT);
 158
 159         status = lttng_destruction_handle_get_result(handle, &ret_code);
 160         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 161                 ERR("%sFailed to get the result of session destruction",
 162                                 newline_needed ? "\n" : "");
 163                 ret = -1;
 164                 newline_needed = false;
 165                 goto error;
 166         }
 167         if (ret_code != LTTNG_OK) {
 168                 ret = -ret_code;
 169                 goto error;
 170         }
 171
 172         status = lttng_destruction_handle_get_rotation_state(
 173                         handle, &rotation_state);
 174         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 175                 ERR("%sFailed to get rotation state from destruction handle",
 176                                 newline_needed ? "\n" : "");
 177                 newline_needed = false;
 178                 goto skip_wait_rotation;
 179         }
 180
 181         switch (rotation_state) {
 182         case LTTNG_ROTATION_STATE_NO_ROTATION:
 183                 break;
 184         case LTTNG_ROTATION_STATE_COMPLETED:
 185         {
 186                 const struct lttng_trace_archive_location *location;
 187
 188                 status = lttng_destruction_handle_get_archive_location(
 189                                 handle, &location);
 190                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 191                         ret = print_trace_archive_location(
 192                                         location, session->name);
 193                         if (ret) {
 194                                 ERR("%sFailed to print the location of trace archive",
 195                                                 newline_needed ? "\n" : "");
 196                                 newline_needed = false;
 197                                 goto skip_wait_rotation;
 198                         }
 199                         break;
 200                 }
 201                 /* fall-through. */
 202         }
 203         default:
 204                 ERR("%sFailed to get the location of the rotation performed during the session's destruction",
 205                                 newline_needed ? "\n" : "");
 206                 newline_needed = false;
 207                 goto skip_wait_rotation;
 208         }
 209 skip_wait_rotation:
 210         MSG("%sSession %s destroyed", newline_needed ? "\n" : "",
 211                         session->name);
 212         newline_needed = false;
 213         if (stats_str) {
 214                 MSG("%s", stats_str);
 215         }
 216
 217         session_name = get_session_name_quiet();
 218         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 219                 config_destroy_default();
 220         }
 221
 222         if (lttng_opt_mi) {
 223                 ret = mi_lttng_session(writer, session, 0);
 224                 if (ret) {
 225                         ret = CMD_ERROR;
 226                         goto error;
 227                 }
 228         }
 229
 230         ret = CMD_SUCCESS;
 231 error:
 232         if (newline_needed) {
 233                 MSG("");
 234         }
 235         lttng_destruction_handle_destroy(handle);
 236         free(session_name);
 237         free(stats_str);
 238         return ret;
 239 }
 240
 241 /*
 242  * destroy_all_sessions
 243  *
 244  * Call destroy_sessions for each registered sessions
 245  */
 246 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 247 {
 248         int i;
 249         bool error_occurred = false;
 250
 251         assert(count >= 0);
 252         if (count == 0) {
 253                 MSG("No session found, nothing to do.");
 254         }
 255
 256         for (i = 0; i < count; i++) {
 257                 int ret = destroy_session(&sessions[i]);
 258
 259                 if (ret < 0) {
 260                         ERR("%s during the destruction of session \"%s\"",
 261                                         lttng_strerror(ret),
 262                                         sessions[i].name);
 263                         /* Continue to next session. */
 264                         error_occurred = true;
 265                 }
 266         }
 267
 268         return error_occurred ? CMD_ERROR : CMD_SUCCESS;
 269 }
 270
 271 /*
 272  * The 'destroy <options>' first level command
 273  */
 274 int cmd_destroy(int argc, const char **argv)
 275 {
 276         int opt;
 277         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 278         static poptContext pc;
 279         char *session_name = NULL;
 280         const char *leftover = NULL;
 281
 282         struct lttng_session *sessions;
 283         int count;
 284         int found;
 285
 286         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 287         poptReadDefaultConfig(pc, 0);
 288
 289         while ((opt = poptGetNextOpt(pc)) != -1) {
 290                 switch (opt) {
 291                 case OPT_HELP:
 292                         SHOW_HELP();
 293                         break;
 294                 case OPT_LIST_OPTIONS:
 295                         list_cmd_options(stdout, long_options);
 296                         break;
 297                 default:
 298                         ret = CMD_UNDEFINED;
 299                         break;
 300                 }
 301                 goto end;
 302         }
 303
 304         /* Mi preparation */
 305         if (lttng_opt_mi) {
 306                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 307                 if (!writer) {
 308                         ret = -LTTNG_ERR_NOMEM;
 309                         goto end;
 310                 }
 311
 312                 /* Open command element */
 313                 ret = mi_lttng_writer_command_open(writer,
 314                                 mi_lttng_element_command_destroy);
 315                 if (ret) {
 316                         ret = CMD_ERROR;
 317                         goto end;
 318                 }
 319
 320                 /* Open output element */
 321                 ret = mi_lttng_writer_open_element(writer,
 322                                 mi_lttng_element_command_output);
 323                 if (ret) {
 324                         ret = CMD_ERROR;
 325                         goto end;
 326                 }
 327
 328                 /* For validation and semantic purpose we open a sessions element */
 329                 ret = mi_lttng_sessions_open(writer);
 330                 if (ret) {
 331                         ret = CMD_ERROR;
 332                         goto end;
 333                 }
 334         }
 335
 336         /* Recuperate all sessions for further operation */
 337         count = lttng_list_sessions(&sessions);
 338         if (count < 0) {
 339                 ERR("%s", lttng_strerror(count));
 340                 command_ret = CMD_ERROR;
 341                 success = 0;
 342                 goto mi_closing;
 343         }
 344
 345         /* Ignore session name in case all sessions are to be destroyed */
 346         if (opt_destroy_all) {
 347                 command_ret = destroy_all_sessions(sessions, count);
 348                 if (command_ret) {
 349                         success = 0;
 350                 }
 351         } else {
 352                 opt_session_name = (char *) poptGetArg(pc);
 353
 354                 if (!opt_session_name) {
 355                         /* No session name specified, lookup default */
 356                         session_name = get_session_name();
 357                         if (session_name == NULL) {
 358                                 command_ret = CMD_ERROR;
 359                                 success = 0;
 360                                 goto mi_closing;
 361                         }
 362                 } else {
 363                         session_name = opt_session_name;
 364                 }
 365
 366                 /* Find the corresponding lttng_session struct */
 367                 found = 0;
 368                 for (i = 0; i < count; i++) {
 369                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 370                                 found = 1;
 371                                 command_ret = destroy_session(&sessions[i]);
 372                                 if (command_ret) {
 373                                         success = 0;
 374                                         ERR("%s during the destruction of session \"%s\"",
 375                                                         lttng_strerror(command_ret),
 376                                                         sessions[i].name);
 377                                 }
 378                         }
 379                 }
 380
 381                 if (!found) {
 382                         ERR("Session name %s not found", session_name);
 383                         command_ret = LTTNG_ERR_SESS_NOT_FOUND;
 384                         success = 0;
 385                         goto mi_closing;
 386                 }
 387         }
 388
 389         leftover = poptGetArg(pc);
 390         if (leftover) {
 391                 ERR("Unknown argument: %s", leftover);
 392                 ret = CMD_ERROR;
 393                 success = 0;
 394                 goto mi_closing;
 395         }
 396
 397 mi_closing:
 398         /* Mi closing */
 399         if (lttng_opt_mi) {
 400                 /* Close sessions and output element element */
 401                 ret = mi_lttng_close_multi_element(writer, 2);
 402                 if (ret) {
 403                         ret = CMD_ERROR;
 404                         goto end;
 405                 }
 406
 407                 /* Success ? */
 408                 ret = mi_lttng_writer_write_element_bool(writer,
 409                                 mi_lttng_element_command_success, success);
 410                 if (ret) {
 411                         ret = CMD_ERROR;
 412                         goto end;
 413                 }
 414
 415                 /* Command element close */
 416                 ret = mi_lttng_writer_command_close(writer);
 417                 if (ret) {
 418                         ret = CMD_ERROR;
 419                         goto end;
 420                 }
 421         }
 422 end:
 423         /* Mi clean-up */
 424         if (writer && mi_lttng_writer_destroy(writer)) {
 425                 /* Preserve original error code */
 426                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 427         }
 428
 429         if (opt_session_name == NULL) {
 430                 free(session_name);
 431         }
 432
 433         /* Overwrite ret if an error occurred during destroy_session/all */
 434         ret = command_ret ? command_ret : ret;
 435
 436         poptFreeContext(pc);
 437         return ret;
 438 }