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_stopped;
  63         enum lttng_error_code ret_code;
  64         struct lttng_destruction_handle *handle = NULL;
  65         enum lttng_destruction_handle_status status;
  66         bool printed_wait_msg = false;
  67         enum lttng_rotation_state rotation_state;
  68
  69         ret = lttng_stop_tracing_no_wait(session->name);
  70         if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) {
  71                 ERR("%s", lttng_strerror(ret));
  72         }
  73         session_was_stopped = ret == -LTTNG_ERR_TRACE_ALREADY_STOPPED;
  74         if (!opt_no_wait) {
  75                 do {
  76                         ret = lttng_data_pending(session->name);
  77                         if (ret < 0) {
  78                                 /* Return the data available call error. */
  79                                 goto error;
  80                         }
  81
  82                         /*
  83                          * Data sleep time before retrying (in usec). Don't sleep if the call
  84                          * returned value indicates availability.
  85                          */
  86                         if (ret) {
  87                                 if (!printed_wait_msg) {
  88                                         _MSG("Waiting for destruction of session \"%s\"",
  89                                                         session->name);
  90                                         printed_wait_msg = true;
  91                                         fflush(stdout);
  92                                 }
  93
  94                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
  95                                 _MSG(".");
  96                                 fflush(stdout);
  97                         }
  98                 } while (ret != 0);
  99         }
 100         if (!session_was_stopped) {
 101                 /*
 102                  * Don't print the event and packet loss warnings since the user
 103                  * already saw them when stopping the trace.
 104                  */
 105                 print_session_stats(session->name);
 106         }
 107
 108         ret_code = lttng_destroy_session_ext(session->name, &handle);
 109         if (ret_code != LTTNG_OK) {
 110                 ret = -ret_code;
 111                 goto error;
 112         }
 113
 114         if (opt_no_wait) {
 115                 goto skip_wait_rotation;
 116         }
 117
 118         do {
 119                 status = lttng_destruction_handle_wait_for_completion(handle,
 120                                 DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US / USEC_PER_MSEC);
 121                 switch (status) {
 122                 case LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT:
 123                         if (!printed_wait_msg) {
 124                                 _MSG("Waiting for destruction of session \"%s\"",
 125                                                 session->name);
 126                                 printed_wait_msg = true;
 127                         }
 128                         _MSG(".");
 129                         fflush(stdout);
 130                         break;
 131                 case LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED:
 132                         break;
 133                 default:
 134                         ERR("Failed to wait for the completion of the destruction of session \"%s\"",
 135                                         session->name);
 136                         ret = -1;
 137                         goto error;
 138                 }
 139         } while (status == LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT);
 140
 141         status = lttng_destruction_handle_get_result(handle, &ret_code);
 142         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 143                 ERR("Failed to get the result of session destruction");
 144                 ret = -1;
 145                 goto error;
 146         }
 147         if (ret_code != LTTNG_OK) {
 148                 ret = -ret_code;
 149                 goto error;
 150         }
 151
 152         status = lttng_destruction_handle_get_rotation_state(handle,
 153                         &rotation_state);
 154         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 155                 ERR("Failed to get rotation state from destruction handle");
 156                 goto skip_wait_rotation;
 157         }
 158         switch (rotation_state) {
 159         case LTTNG_ROTATION_STATE_NO_ROTATION:
 160                 break;
 161         case LTTNG_ROTATION_STATE_COMPLETED:
 162         {
 163                 const struct lttng_trace_archive_location *location;
 164
 165                 status = lttng_destruction_handle_get_archive_location(handle,
 166                                 &location);
 167                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 168                         if (printed_wait_msg) {
 169                                 MSG("");
 170                                 printed_wait_msg = false;
 171                         }
 172                         ret = print_trace_archive_location(location,
 173                                         session->name);
 174                         if (ret) {
 175                                 ERR("Failed to print the location of trace archive");
 176                                 goto skip_wait_rotation;
 177                         }
 178                         break;
 179                 }
 180                 /* fall-through. */
 181         }
 182         default:
 183                 ERR("Failed to get the location of the rotation performed during the session's destruction");
 184                 goto skip_wait_rotation;
 185         }
 186 skip_wait_rotation:
 187         MSG("%sSession \"%s\" destroyed", printed_wait_msg ? "\n" : "",
 188                         session->name);
 189         printed_wait_msg = false;
 190
 191         session_name = get_session_name_quiet();
 192         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 193                 config_destroy_default();
 194         }
 195
 196         if (lttng_opt_mi) {
 197                 ret = mi_lttng_session(writer, session, 0);
 198                 if (ret) {
 199                         ret = CMD_ERROR;
 200                         goto error;
 201                 }
 202         }
 203
 204         ret = CMD_SUCCESS;
 205 error:
 206         if (printed_wait_msg) {
 207                 MSG("");
 208         }
 209         lttng_destruction_handle_destroy(handle);
 210         free(session_name);
 211         return ret;
 212 }
 213
 214 /*
 215  * destroy_all_sessions
 216  *
 217  * Call destroy_sessions for each registered sessions
 218  */
 219 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 220 {
 221         int i;
 222         bool error_occurred = false;
 223
 224         assert(count >= 0);
 225         if (count == 0) {
 226                 MSG("No session found, nothing to do.");
 227         }
 228
 229         for (i = 0; i < count; i++) {
 230                 int ret = destroy_session(&sessions[i]);
 231
 232                 if (ret < 0) {
 233                         ERR("%s during the destruction of session \"%s\"",
 234                                         lttng_strerror(ret),
 235                                         sessions[i].name);
 236                         /* Continue to next session. */
 237                         error_occurred = true;
 238                 }
 239         }
 240
 241         return error_occurred ? CMD_ERROR : CMD_SUCCESS;
 242 }
 243
 244 /*
 245  * The 'destroy <options>' first level command
 246  */
 247 int cmd_destroy(int argc, const char **argv)
 248 {
 249         int opt;
 250         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 251         static poptContext pc;
 252         char *session_name = NULL;
 253         const char *leftover = NULL;
 254
 255         struct lttng_session *sessions;
 256         int count;
 257         int found;
 258
 259         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 260         poptReadDefaultConfig(pc, 0);
 261
 262         while ((opt = poptGetNextOpt(pc)) != -1) {
 263                 switch (opt) {
 264                 case OPT_HELP:
 265                         SHOW_HELP();
 266                         break;
 267                 case OPT_LIST_OPTIONS:
 268                         list_cmd_options(stdout, long_options);
 269                         break;
 270                 default:
 271                         ret = CMD_UNDEFINED;
 272                         break;
 273                 }
 274                 goto end;
 275         }
 276
 277         /* Mi preparation */
 278         if (lttng_opt_mi) {
 279                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 280                 if (!writer) {
 281                         ret = -LTTNG_ERR_NOMEM;
 282                         goto end;
 283                 }
 284
 285                 /* Open command element */
 286                 ret = mi_lttng_writer_command_open(writer,
 287                                 mi_lttng_element_command_destroy);
 288                 if (ret) {
 289                         ret = CMD_ERROR;
 290                         goto end;
 291                 }
 292
 293                 /* Open output element */
 294                 ret = mi_lttng_writer_open_element(writer,
 295                                 mi_lttng_element_command_output);
 296                 if (ret) {
 297                         ret = CMD_ERROR;
 298                         goto end;
 299                 }
 300
 301                 /* For validation and semantic purpose we open a sessions element */
 302                 ret = mi_lttng_sessions_open(writer);
 303                 if (ret) {
 304                         ret = CMD_ERROR;
 305                         goto end;
 306                 }
 307         }
 308
 309         /* Recuperate all sessions for further operation */
 310         count = lttng_list_sessions(&sessions);
 311         if (count < 0) {
 312                 ERR("%s", lttng_strerror(count));
 313                 command_ret = CMD_ERROR;
 314                 success = 0;
 315                 goto mi_closing;
 316         }
 317
 318         /* Ignore session name in case all sessions are to be destroyed */
 319         if (opt_destroy_all) {
 320                 command_ret = destroy_all_sessions(sessions, count);
 321                 if (command_ret) {
 322                         success = 0;
 323                 }
 324         } else {
 325                 opt_session_name = (char *) poptGetArg(pc);
 326
 327                 if (!opt_session_name) {
 328                         /* No session name specified, lookup default */
 329                         session_name = get_session_name();
 330                         if (session_name == NULL) {
 331                                 command_ret = CMD_ERROR;
 332                                 success = 0;
 333                                 goto mi_closing;
 334                         }
 335                 } else {
 336                         session_name = opt_session_name;
 337                 }
 338
 339                 /* Find the corresponding lttng_session struct */
 340                 found = 0;
 341                 for (i = 0; i < count; i++) {
 342                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 343                                 found = 1;
 344                                 command_ret = destroy_session(&sessions[i]);
 345                                 if (command_ret) {
 346                                         success = 0;
 347                                         ERR("%s during the destruction of session \"%s\"",
 348                                                         lttng_strerror(command_ret),
 349                                                         sessions[i].name);
 350                                 }
 351                         }
 352                 }
 353
 354                 if (!found) {
 355                         ERR("Session name %s not found", session_name);
 356                         command_ret = LTTNG_ERR_SESS_NOT_FOUND;
 357                         success = 0;
 358                         goto mi_closing;
 359                 }
 360         }
 361
 362         leftover = poptGetArg(pc);
 363         if (leftover) {
 364                 ERR("Unknown argument: %s", leftover);
 365                 ret = CMD_ERROR;
 366                 success = 0;
 367                 goto mi_closing;
 368         }
 369
 370 mi_closing:
 371         /* Mi closing */
 372         if (lttng_opt_mi) {
 373                 /* Close sessions and output element element */
 374                 ret = mi_lttng_close_multi_element(writer, 2);
 375                 if (ret) {
 376                         ret = CMD_ERROR;
 377                         goto end;
 378                 }
 379
 380                 /* Success ? */
 381                 ret = mi_lttng_writer_write_element_bool(writer,
 382                                 mi_lttng_element_command_success, success);
 383                 if (ret) {
 384                         ret = CMD_ERROR;
 385                         goto end;
 386                 }
 387
 388                 /* Command element close */
 389                 ret = mi_lttng_writer_command_close(writer);
 390                 if (ret) {
 391                         ret = CMD_ERROR;
 392                         goto end;
 393                 }
 394         }
 395 end:
 396         /* Mi clean-up */
 397         if (writer && mi_lttng_writer_destroy(writer)) {
 398                 /* Preserve original error code */
 399                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 400         }
 401
 402         if (opt_session_name == NULL) {
 403                 free(session_name);
 404         }
 405
 406         /* Overwrite ret if an error occurred during destroy_session/all */
 407         ret = command_ret ? command_ret : ret;
 408
 409         poptFreeContext(pc);
 410         return ret;
 411 }