src/bin/lttng/commands/destroy.cpp

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