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                                 _MSG("Destroying session %s", session->name);
  91                                 newline_needed = true;
  92                                 printed_destroy_msg = true;
  93                                 fflush(stdout);
  94
  95                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
  96                                 _MSG(".");
  97                                 fflush(stdout);
  98                         }
  99                 } while (ret != 0);
 100         }
 101
 102         if (!session_was_already_stopped) {
 103                 /*
 104                  * Don't print the event and packet loss warnings since the user
 105                  * already saw them when stopping the trace.
 106                  */
 107                 ret = get_session_stats_str(session->name, &stats_str);
 108                 if (ret < 0) {
 109                         goto error;
 110                 }
 111         }
 112
 113         ret_code = lttng_destroy_session_ext(session->name, &handle);
 114         if (ret_code != LTTNG_OK) {
 115                 ret = -ret_code;
 116                 goto error;
 117         }
 118
 119         if (opt_no_wait) {
 120                 goto skip_wait_rotation;
 121         }
 122
 123         do {
 124                 status = lttng_destruction_handle_wait_for_completion(
 125                                 handle, DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US /
 126                                                         USEC_PER_MSEC);
 127                 switch (status) {
 128                 case LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT:
 129                         if (!printed_destroy_msg) {
 130                                 _MSG("Destroying session %s", session->name);
 131                                 newline_needed = true;
 132                                 printed_destroy_msg = true;
 133                         }
 134                         _MSG(".");
 135                         fflush(stdout);
 136                         break;
 137                 case LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED:
 138                         break;
 139                 default:
 140                         ERR("%sFailed to wait for the completion of the destruction of session \"%s\"",
 141                                         newline_needed ? "\n" : "",
 142                                         session->name);
 143                         newline_needed = false;
 144                         ret = -1;
 145                         goto error;
 146                 }
 147         } while (status == LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT);
 148
 149         status = lttng_destruction_handle_get_result(handle, &ret_code);
 150         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 151                 ERR("%sFailed to get the result of session destruction",
 152                                 newline_needed ? "\n" : "");
 153                 ret = -1;
 154                 newline_needed = false;
 155                 goto error;
 156         }
 157         if (ret_code != LTTNG_OK) {
 158                 ret = -ret_code;
 159                 goto error;
 160         }
 161
 162         status = lttng_destruction_handle_get_rotation_state(
 163                         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(
 179                                 handle, &location);
 180                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 181                         ret = print_trace_archive_location(
 182                                         location, session->name);
 183                         if (ret) {
 184                                 ERR("%sFailed to print the location of trace archive",
 185                                                 newline_needed ? "\n" : "");
 186                                 newline_needed = false;
 187                                 goto skip_wait_rotation;
 188                         }
 189                         break;
 190                 }
 191                 /* fall-through. */
 192         }
 193         default:
 194                 ERR("%sFailed to get the location of the rotation performed during the session's destruction",
 195                                 newline_needed ? "\n" : "");
 196                 newline_needed = false;
 197                 goto skip_wait_rotation;
 198         }
 199 skip_wait_rotation:
 200         MSG("%sSession %s destroyed", newline_needed ? "\n" : "",
 201                         session->name);
 202         newline_needed = false;
 203         if (stats_str) {
 204                 MSG("%s", stats_str);
 205         }
 206
 207         session_name = get_session_name_quiet();
 208         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 209                 config_destroy_default();
 210         }
 211
 212         if (lttng_opt_mi) {
 213                 ret = mi_lttng_session(writer, session, 0);
 214                 if (ret) {
 215                         ret = CMD_ERROR;
 216                         goto error;
 217                 }
 218         }
 219
 220         ret = CMD_SUCCESS;
 221 error:
 222         if (newline_needed) {
 223                 MSG("");
 224         }
 225         lttng_destruction_handle_destroy(handle);
 226         free(session_name);
 227         free(stats_str);
 228         return ret;
 229 }
 230
 231 /*
 232  * destroy_all_sessions
 233  *
 234  * Call destroy_sessions for each registered sessions
 235  */
 236 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 237 {
 238         int i;
 239         bool error_occurred = false;
 240
 241         assert(count >= 0);
 242         if (count == 0) {
 243                 MSG("No session found, nothing to do.");
 244         }
 245
 246         for (i = 0; i < count; i++) {
 247                 int ret = destroy_session(&sessions[i]);
 248
 249                 if (ret < 0) {
 250                         ERR("%s during the destruction of session \"%s\"",
 251                                         lttng_strerror(ret),
 252                                         sessions[i].name);
 253                         /* Continue to next session. */
 254                         error_occurred = true;
 255                 }
 256         }
 257
 258         return error_occurred ? CMD_ERROR : CMD_SUCCESS;
 259 }
 260
 261 /*
 262  * The 'destroy <options>' first level command
 263  */
 264 int cmd_destroy(int argc, const char **argv)
 265 {
 266         int opt;
 267         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 268         static poptContext pc;
 269         char *session_name = NULL;
 270         const char *leftover = NULL;
 271
 272         struct lttng_session *sessions;
 273         int count;
 274         int found;
 275
 276         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 277         poptReadDefaultConfig(pc, 0);
 278
 279         while ((opt = poptGetNextOpt(pc)) != -1) {
 280                 switch (opt) {
 281                 case OPT_HELP:
 282                         SHOW_HELP();
 283                         break;
 284                 case OPT_LIST_OPTIONS:
 285                         list_cmd_options(stdout, long_options);
 286                         break;
 287                 default:
 288                         ret = CMD_UNDEFINED;
 289                         break;
 290                 }
 291                 goto end;
 292         }
 293
 294         /* Mi preparation */
 295         if (lttng_opt_mi) {
 296                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 297                 if (!writer) {
 298                         ret = -LTTNG_ERR_NOMEM;
 299                         goto end;
 300                 }
 301
 302                 /* Open command element */
 303                 ret = mi_lttng_writer_command_open(writer,
 304                                 mi_lttng_element_command_destroy);
 305                 if (ret) {
 306                         ret = CMD_ERROR;
 307                         goto end;
 308                 }
 309
 310                 /* Open output element */
 311                 ret = mi_lttng_writer_open_element(writer,
 312                                 mi_lttng_element_command_output);
 313                 if (ret) {
 314                         ret = CMD_ERROR;
 315                         goto end;
 316                 }
 317
 318                 /* For validation and semantic purpose we open a sessions element */
 319                 ret = mi_lttng_sessions_open(writer);
 320                 if (ret) {
 321                         ret = CMD_ERROR;
 322                         goto end;
 323                 }
 324         }
 325
 326         /* Recuperate all sessions for further operation */
 327         count = lttng_list_sessions(&sessions);
 328         if (count < 0) {
 329                 ERR("%s", lttng_strerror(count));
 330                 command_ret = CMD_ERROR;
 331                 success = 0;
 332                 goto mi_closing;
 333         }
 334
 335         /* Ignore session name in case all sessions are to be destroyed */
 336         if (opt_destroy_all) {
 337                 command_ret = destroy_all_sessions(sessions, count);
 338                 if (command_ret) {
 339                         success = 0;
 340                 }
 341         } else {
 342                 opt_session_name = (char *) poptGetArg(pc);
 343
 344                 if (!opt_session_name) {
 345                         /* No session name specified, lookup default */
 346                         session_name = get_session_name();
 347                         if (session_name == NULL) {
 348                                 command_ret = CMD_ERROR;
 349                                 success = 0;
 350                                 goto mi_closing;
 351                         }
 352                 } else {
 353                         session_name = opt_session_name;
 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(writer,
 399                                 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         if (opt_session_name == NULL) {
 420                 free(session_name);
 421         }
 422
 423         /* Overwrite ret if an error occurred during destroy_session/all */
 424         ret = command_ret ? command_ret : ret;
 425
 426         poptFreeContext(pc);
 427         return ret;
 428 }