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