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_US);
 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_US / USEC_PER_MSEC);
 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         if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 165                 ERR("Failed to get rotation state from destruction handle");
 166                 goto skip_wait_rotation;
 167         }
 168         switch (rotation_state) {
 169         case LTTNG_ROTATION_STATE_NO_ROTATION:
 170                 break;
 171         case LTTNG_ROTATION_STATE_COMPLETED:
 172         {
 173                 const struct lttng_trace_archive_location *location;
 174
 175                 status = lttng_destruction_handle_get_archive_location(handle,
 176                                 &location);
 177                 if (status == LTTNG_DESTRUCTION_HANDLE_STATUS_OK) {
 178                         if (printed_wait_msg) {
 179                                 MSG("");
 180                                 printed_wait_msg = false;
 181                         }
 182                         ret = print_trace_archive_location(location,
 183                                         session->name);
 184                         if (ret) {
 185                                 ERR("Failed to print the location of trace archive");
 186                                 goto skip_wait_rotation;
 187                         }
 188                         break;
 189                 }
 190                 /* fall-through. */
 191         }
 192         default:
 193                 ERR("Failed to get the location of the rotation performed during the session's destruction");
 194                 goto skip_wait_rotation;
 195         }
 196 skip_wait_rotation:
 197         MSG("%sSession \"%s\" destroyed", printed_wait_msg ? "\n" : "",
 198                         session->name);
 199         printed_wait_msg = false;
 200
 201         session_name = get_session_name_quiet();
 202         if (session_name && !strncmp(session->name, session_name, NAME_MAX)) {
 203                 config_destroy_default();
 204         }
 205
 206         if (lttng_opt_mi) {
 207                 ret = mi_lttng_session(writer, session, 0);
 208                 if (ret) {
 209                         ret = CMD_ERROR;
 210                         goto error;
 211                 }
 212         }
 213
 214         ret = CMD_SUCCESS;
 215 error:
 216         if (printed_wait_msg) {
 217                 MSG("");
 218         }
 219         lttng_destruction_handle_destroy(handle);
 220         free(session_name);
 221         return ret;
 222 }
 223
 224 /*
 225  * destroy_all_sessions
 226  *
 227  * Call destroy_sessions for each registered sessions
 228  */
 229 static int destroy_all_sessions(struct lttng_session *sessions, int count)
 230 {
 231         int i, ret = CMD_SUCCESS;
 232
 233         if (count == 0) {
 234                 MSG("No session found, nothing to do.");
 235         } else if (count < 0) {
 236                 ERR("%s", lttng_strerror(ret));
 237                 goto error;
 238         }
 239
 240         for (i = 0; i < count; i++) {
 241                 ret = destroy_session(&sessions[i]);
 242                 if (ret < 0) {
 243                         goto error;
 244                 }
 245         }
 246 error:
 247         return ret;
 248 }
 249
 250 /*
 251  * The 'destroy <options>' first level command
 252  */
 253 int cmd_destroy(int argc, const char **argv)
 254 {
 255         int opt;
 256         int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
 257         static poptContext pc;
 258         char *session_name = NULL;
 259         const char *leftover = NULL;
 260
 261         struct lttng_session *sessions;
 262         int count;
 263         int found;
 264
 265         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 266         poptReadDefaultConfig(pc, 0);
 267
 268         while ((opt = poptGetNextOpt(pc)) != -1) {
 269                 switch (opt) {
 270                 case OPT_HELP:
 271                         SHOW_HELP();
 272                         break;
 273                 case OPT_LIST_OPTIONS:
 274                         list_cmd_options(stdout, long_options);
 275                         break;
 276                 default:
 277                         ret = CMD_UNDEFINED;
 278                         break;
 279                 }
 280                 goto end;
 281         }
 282
 283         /* Mi preparation */
 284         if (lttng_opt_mi) {
 285                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 286                 if (!writer) {
 287                         ret = -LTTNG_ERR_NOMEM;
 288                         goto end;
 289                 }
 290
 291                 /* Open command element */
 292                 ret = mi_lttng_writer_command_open(writer,
 293                                 mi_lttng_element_command_destroy);
 294                 if (ret) {
 295                         ret = CMD_ERROR;
 296                         goto end;
 297                 }
 298
 299                 /* Open output element */
 300                 ret = mi_lttng_writer_open_element(writer,
 301                                 mi_lttng_element_command_output);
 302                 if (ret) {
 303                         ret = CMD_ERROR;
 304                         goto end;
 305                 }
 306
 307                 /* For validation and semantic purpose we open a sessions element */
 308                 ret = mi_lttng_sessions_open(writer);
 309                 if (ret) {
 310                         ret = CMD_ERROR;
 311                         goto end;
 312                 }
 313         }
 314
 315         /* Recuperate all sessions for further operation */
 316         count = lttng_list_sessions(&sessions);
 317         if (count < 0) {
 318                 ERR("%s", lttng_strerror(count));
 319                 command_ret = CMD_ERROR;
 320                 success = 0;
 321                 goto mi_closing;
 322         }
 323
 324         /* Ignore session name in case all sessions are to be destroyed */
 325         if (opt_destroy_all) {
 326                 command_ret = destroy_all_sessions(sessions, count);
 327                 if (command_ret) {
 328                         success = 0;
 329                 }
 330         } else {
 331                 opt_session_name = (char *) poptGetArg(pc);
 332
 333                 if (!opt_session_name) {
 334                         /* No session name specified, lookup default */
 335                         session_name = get_session_name();
 336                         if (session_name == NULL) {
 337                                 command_ret = CMD_ERROR;
 338                                 success = 0;
 339                                 goto mi_closing;
 340                         }
 341                 } else {
 342                         session_name = opt_session_name;
 343                 }
 344
 345                 /* Find the corresponding lttng_session struct */
 346                 found = 0;
 347                 for (i = 0; i < count; i++) {
 348                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 349                                 found = 1;
 350                                 command_ret = destroy_session(&sessions[i]);
 351                                 if (command_ret) {
 352                                         success = 0;
 353                                 }
 354
 355                         }
 356                 }
 357
 358                 if (!found) {
 359                         ERR("Session name %s not found", session_name);
 360                         command_ret = LTTNG_ERR_SESS_NOT_FOUND;
 361                         success = 0;
 362                         goto mi_closing;
 363                 }
 364         }
 365
 366         leftover = poptGetArg(pc);
 367         if (leftover) {
 368                 ERR("Unknown argument: %s", leftover);
 369                 ret = CMD_ERROR;
 370                 success = 0;
 371                 goto mi_closing;
 372         }
 373
 374 mi_closing:
 375         /* Mi closing */
 376         if (lttng_opt_mi) {
 377                 /* Close sessions and output element element */
 378                 ret = mi_lttng_close_multi_element(writer, 2);
 379                 if (ret) {
 380                         ret = CMD_ERROR;
 381                         goto end;
 382                 }
 383
 384                 /* Success ? */
 385                 ret = mi_lttng_writer_write_element_bool(writer,
 386                                 mi_lttng_element_command_success, success);
 387                 if (ret) {
 388                         ret = CMD_ERROR;
 389                         goto end;
 390                 }
 391
 392                 /* Command element close */
 393                 ret = mi_lttng_writer_command_close(writer);
 394                 if (ret) {
 395                         ret = CMD_ERROR;
 396                         goto end;
 397                 }
 398         }
 399 end:
 400         /* Mi clean-up */
 401         if (writer && mi_lttng_writer_destroy(writer)) {
 402                 /* Preserve original error code */
 403                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 404         }
 405
 406         if (opt_session_name == NULL) {
 407                 free(session_name);
 408         }
 409
 410         /* Overwrite ret if an error occurred during destroy_session/all */
 411         ret = command_ret ? command_ret : ret;
 412
 413         poptFreeContext(pc);
 414         return ret;
 415 }