src/bin/lttng/commands/destroy.c

   1 /*
   2  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #define _LGPL_SOURCE
   9 #include <popt.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/stat.h>
  14 #include <sys/types.h>
  15 #include <unistd.h>
  16 #include <stdbool.h>
  17 #include <lttng/lttng.h>
  18
  19 #include "../command.h"
  20
  21 #include <common/mi-lttng.h>
  22 #include <common/sessiond-comm/sessiond-comm.h>
  23 #include <common/utils.h>
  24
  25 static char *opt_session_name;
  26 static int opt_destroy_all;
  27 static int opt_no_wait;
  28
  29 #ifdef LTTNG_EMBED_HELP
  30 static const char help_msg[] =
  31 #include <lttng-destroy.1.h>
  32 ;
  33 #endif
  34
  35 /* Mi writer */
  36 static struct mi_writer *writer;
  37
  38 enum {
  39         OPT_HELP = 1,
  40         OPT_LIST_OPTIONS,
  41 };
  42
  43 static struct poptOption long_options[] = {
  44         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  45         {"help",      'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  46         {"all",       'a', POPT_ARG_VAL, &opt_destroy_all, 1, 0, 0},
  47         {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  48         {"no-wait",   'n', POPT_ARG_VAL, &opt_no_wait, 1, 0, 0},
  49         {0, 0, 0, 0, 0, 0, 0}
  50 };
  51
  52 /*
  53  * destroy_session
  54  *
  55  * Unregister the provided session to the session daemon. On success, removes
  56  * the default configuration.
  57  */
  58 static int destroy_session(struct lttng_session *session)
  59 {
  60         int ret;
  61         char *session_name = NULL;
  62         bool session_was_already_stopped;
  63         enum lttng_error_code ret_code;
  64         struct lttng_destruction_handle *handle = NULL;
  65         enum lttng_destruction_handle_status status;
  66         bool newline_needed = false, printed_destroy_msg = false;
  67         enum lttng_rotation_state rotation_state;
  68         char *stats_str = NULL;
  69
  70         ret = lttng_stop_tracing_no_wait(session->name);
  71         if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
  72                 ERR("%s", lttng_strerror(ret));
  73         }
  74
  75         session_was_already_stopped = ret == -LTTNG_ERR_TRACE_ALREADY_STOPPED;
  76         if (!opt_no_wait) {
  77                 do {
  78                         ret = lttng_data_pending(session->name);
  79                         if (ret < 0) {
  80                                 /* Return the data available call error. */
  81                                 goto error;
  82                         }
  83
  84                         /*
  85                          * Data sleep time before retrying (in usec). Don't
  86                          * sleep if the call returned value indicates
  87                          * availability.
  88                          */
  89                         if (ret) {
  90                                 if (!printed_destroy_msg) {
  91                                         _MSG("Destroying session %s",
  92                                                         session->name);
  93                                         newline_needed = true;
  94                                         printed_destroy_msg = true;
  95                                         fflush(stdout);
  96                                 }
  97
  98                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
  99                                 _MSG(".");
 100                                 fflush(stdout);
 101                         }
 102                 } while (ret != 0);
 103         }
 104
 105         if (!session_was_already_stopped) {
 106                 /*
 107                  * Don't print the event and packet loss warnings since the user
 108                  * already saw them when stopping the trace.
 109                  */
 110                 ret = get_session_stats_str(session->name, &stats_str);
 111                 if (ret < 0) {
 112                         goto error;
 113                 }
 114         }
 115
 116         ret_code = lttng_destroy_session_ext(session->name, &handle);
 117         if (ret_code != LTTNG_OK) {
 118                 ret = -ret_code;
 119                 goto error;
 120         }
 121
 122         if (opt_no_wait) {
 123                 goto skip_wait_rotation;
 124         }
 125
 126         do {
 127                 status = lttng_destruction_handle_wait_for_completion(
 128                                 handle, DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US /
 129                                                         USEC_PER_MSEC);
 130                 switch (status) {
 131                 case LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT:
 132                         if (!printed_destroy_msg) {
 133                                 _MSG("Destroying session %s", session->name);
 134                                 newline_needed = true;
 135                                 printed_destroy_msg = true;
 136                         }
 137                         _MSG(".");
 138                         fflush(stdout);
 139                         break;
 140                 case LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED:
 141                         break;
 142                 default:
 143                         ERR("%sFailed to wait for the completion of the destruction of session \"%s\"",
 144                                         newline_needed ? "\n" : "",
 145                                         session->name);
 146                         newline_needed = false;
 147                         ret = -1;
 148                         goto error;
 149                 }
 150         } while (status == LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT);
 151
 152         status = lttng_destruction_handle_get_result(handle, &ret_code);
 153         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 154                 ERR("%sFailed to get the result of session destruction",
 155                                 newline_needed ? "\n" : "");
 156                 ret = -1;
 157                 newline_needed = false;
 158                 goto error;
 159         }
 160         if (ret_code != LTTNG_OK) {
 161                 ret = -ret_code;
 162                 goto error;
 163         }
 164
 165         status = lttng_destruction_handle_get_rotation_state(
 166                         handle, &rotation_state);
 167         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 168                 ERR("%sFailed to get rotation state from destruction handle",
 169                                 newline_needed ? "\n" : "");
 170                 newline_needed = false;
 171                 goto skip_wait_rotation;
 172         }
 173
 174         switch (rotation_state) {
 175         case LTTNG_ROTATION_STATE_NO_ROTATION:
 176                 break;
 177         case LTTNG_ROTATION_STATE_COMPLETED:
 178         {
 179                 const struct lttng_trace_archive_location *location;
 180
 181                 status = lttng_destruction_handle_get_archive_location(
 182                                 handle, &location);
 183                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 184                         ret = print_trace_archive_location(
 185                                         location, session->name);
 186                         if (ret) {
 187                                 ERR("%sFailed to print the location of trace archive",
 188                                                 newline_needed ? "\n" : "");
 189                                 newline_needed = false;
 190                                 goto skip_wait_rotation;
 191                         }
 192                         break;
 193                 }
 194                 /* fall-through. */
 195         }
 196         default:
 197                 ERR("%sFailed to get the location of the rotation performed during the session's destruction",
 198                                 newline_needed ? "\n" : "");
 199                 newline_needed = false;
 200                 goto skip_wait_rotation;
 201         }
 202 skip_wait_rotation:
 203         MSG("%sSession %s destroyed", newline_needed ? "\n" : "",
 204                         session->name);
 205         newline_needed = false;
 206         if (stats_str) {
 207                 MSG("%s", stats_str);
 208         }
 209
 210         session_name = get_session_name_quiet();
 211         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 212                 config_destroy_default();
 213         }
 214
 215         if (lttng_opt_mi) {
 216                 ret = mi_lttng_session(writer, session, 0);
 217                 if (ret) {
 218                         ret = CMD_ERROR;
 219                         goto error;
 220                 }
 221         }
 222
 223         ret = CMD_SUCCESS;
 224 error:
 225         if (newline_needed) {
 226                 MSG("");
 227         }
 228         lttng_destruction_handle_destroy(handle);
 229         free(session_name);
 230         free(stats_str);
 231         return ret;
 232 }
 233
 234 /*
 235  * destroy_all_sessions
 236  *
 237  * Call destroy_sessions for each registered sessions
 238  */
 239 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 240 {
 241         int i;
 242         bool error_occurred = false;
 243
 244         assert(count >= 0);
 245         if (count == 0) {
 246                 MSG("No session found, nothing to do.");
 247         }
 248
 249         for (i = 0; i < count; i++) {
 250                 int ret = destroy_session(&sessions[i]);
 251
 252                 if (ret < 0) {
 253                         ERR("%s during the destruction of session \"%s\"",
 254                                         lttng_strerror(ret),
 255                                         sessions[i].name);
 256                         /* Continue to next session. */
 257                         error_occurred = true;
 258                 }
 259         }
 260
 261         return error_occurred ? CMD_ERROR : CMD_SUCCESS;
 262 }
 263
 264 /*
 265  * The 'destroy <options>' first level command
 266  */
 267 int cmd_destroy(int argc, const char **argv)
 268 {
 269         int opt;
 270         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 271         static poptContext pc;
 272         char *session_name = NULL;
 273         const char *leftover = NULL;
 274
 275         struct lttng_session *sessions;
 276         int count;
 277         int found;
 278
 279         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 280         poptReadDefaultConfig(pc, 0);
 281
 282         while ((opt = poptGetNextOpt(pc)) != -1) {
 283                 switch (opt) {
 284                 case OPT_HELP:
 285                         SHOW_HELP();
 286                         break;
 287                 case OPT_LIST_OPTIONS:
 288                         list_cmd_options(stdout, long_options);
 289                         break;
 290                 default:
 291                         ret = CMD_UNDEFINED;
 292                         break;
 293                 }
 294                 goto end;
 295         }
 296
 297         /* Mi preparation */
 298         if (lttng_opt_mi) {
 299                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 300                 if (!writer) {
 301                         ret = -LTTNG_ERR_NOMEM;
 302                         goto end;
 303                 }
 304
 305                 /* Open command element */
 306                 ret = mi_lttng_writer_command_open(writer,
 307                                 mi_lttng_element_command_destroy);
 308                 if (ret) {
 309                         ret = CMD_ERROR;
 310                         goto end;
 311                 }
 312
 313                 /* Open output element */
 314                 ret = mi_lttng_writer_open_element(writer,
 315                                 mi_lttng_element_command_output);
 316                 if (ret) {
 317                         ret = CMD_ERROR;
 318                         goto end;
 319                 }
 320
 321                 /* For validation and semantic purpose we open a sessions element */
 322                 ret = mi_lttng_sessions_open(writer);
 323                 if (ret) {
 324                         ret = CMD_ERROR;
 325                         goto end;
 326                 }
 327         }
 328
 329         /* Recuperate all sessions for further operation */
 330         count = lttng_list_sessions(&sessions);
 331         if (count < 0) {
 332                 ERR("%s", lttng_strerror(count));
 333                 command_ret = CMD_ERROR;
 334                 success = 0;
 335                 goto mi_closing;
 336         }
 337
 338         /* Ignore session name in case all sessions are to be destroyed */
 339         if (opt_destroy_all) {
 340                 command_ret = destroy_all_sessions(sessions, count);
 341                 if (command_ret) {
 342                         success = 0;
 343                 }
 344         } else {
 345                 opt_session_name = (char *) poptGetArg(pc);
 346
 347                 if (!opt_session_name) {
 348                         /* No session name specified, lookup default */
 349                         session_name = get_session_name();
 350                         if (session_name == NULL) {
 351                                 command_ret = CMD_ERROR;
 352                                 success = 0;
 353                                 goto mi_closing;
 354                         }
 355                 } else {
 356                         session_name = opt_session_name;
 357                 }
 358
 359                 /* Find the corresponding lttng_session struct */
 360                 found = 0;
 361                 for (i = 0; i < count; i++) {
 362                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 363                                 found = 1;
 364                                 command_ret = destroy_session(&sessions[i]);
 365                                 if (command_ret) {
 366                                         success = 0;
 367                                         ERR("%s during the destruction of session \"%s\"",
 368                                                         lttng_strerror(command_ret),
 369                                                         sessions[i].name);
 370                                 }
 371                         }
 372                 }
 373
 374                 if (!found) {
 375                         ERR("Session name %s not found", session_name);
 376                         command_ret = LTTNG_ERR_SESS_NOT_FOUND;
 377                         success = 0;
 378                         goto mi_closing;
 379                 }
 380         }
 381
 382         leftover = poptGetArg(pc);
 383         if (leftover) {
 384                 ERR("Unknown argument: %s", leftover);
 385                 ret = CMD_ERROR;
 386                 success = 0;
 387                 goto mi_closing;
 388         }
 389
 390 mi_closing:
 391         /* Mi closing */
 392         if (lttng_opt_mi) {
 393                 /* Close sessions and output element element */
 394                 ret = mi_lttng_close_multi_element(writer, 2);
 395                 if (ret) {
 396                         ret = CMD_ERROR;
 397                         goto end;
 398                 }
 399
 400                 /* Success ? */
 401                 ret = mi_lttng_writer_write_element_bool(writer,
 402                                 mi_lttng_element_command_success, success);
 403                 if (ret) {
 404                         ret = CMD_ERROR;
 405                         goto end;
 406                 }
 407
 408                 /* Command element close */
 409                 ret = mi_lttng_writer_command_close(writer);
 410                 if (ret) {
 411                         ret = CMD_ERROR;
 412                         goto end;
 413                 }
 414         }
 415 end:
 416         /* Mi clean-up */
 417         if (writer && mi_lttng_writer_destroy(writer)) {
 418                 /* Preserve original error code */
 419                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 420         }
 421
 422         if (opt_session_name == NULL) {
 423                 free(session_name);
 424         }
 425
 426         /* Overwrite ret if an error occurred during destroy_session/all */
 427         ret = command_ret ? command_ret : ret;
 428
 429         poptFreeContext(pc);
 430         return ret;
 431 }