src/bin/lttng/commands/stop.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 #include "../utils.hpp"
  11
  12 #include <common/exception.hpp>
  13 #include <common/mi-lttng.hpp>
  14 #include <common/sessiond-comm/sessiond-comm.hpp>
  15
  16 #include <popt.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <sys/stat.h>
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23
  24 enum {
  25         OPT_HELP = 1,
  26         OPT_LIST_OPTIONS,
  27         OPT_ENABLE_GLOB,
  28         OPT_ALL,
  29 };
  30
  31 namespace {
  32 int opt_no_wait;
  33 struct mi_writer *writer;
  34
  35 #ifdef LTTNG_EMBED_HELP
  36 const char help_msg[] =
  37 #include <lttng-stop.1.h>
  38         ;
  39 #endif
  40
  41 struct poptOption long_options[] = {
  42         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  43         { "help", 'h', POPT_ARG_NONE, nullptr, OPT_HELP, nullptr, nullptr },
  44         { "list-options", 0, POPT_ARG_NONE, nullptr, OPT_LIST_OPTIONS, nullptr, nullptr },
  45         { "no-wait", 'n', POPT_ARG_VAL, &opt_no_wait, 1, nullptr, nullptr },
  46         { "glob", 'g', POPT_ARG_NONE, nullptr, OPT_ENABLE_GLOB, nullptr, nullptr },
  47         { "all", 'a', POPT_ARG_NONE, nullptr, OPT_ALL, nullptr, nullptr },
  48         { nullptr, 0, 0, nullptr, 0, nullptr, nullptr }
  49 };
  50
  51 /*
  52  * Mi print of partial session
  53  */
  54 int mi_print_session(const char *session_name, int enabled)
  55 {
  56         int ret;
  57         LTTNG_ASSERT(writer);
  58         LTTNG_ASSERT(session_name);
  59
  60         /* Open session element */
  61         ret = mi_lttng_writer_open_element(writer, config_element_session);
  62         if (ret) {
  63                 goto end;
  64         }
  65
  66         /* Print session name element */
  67         ret = mi_lttng_writer_write_element_string(writer, config_element_name, session_name);
  68         if (ret) {
  69                 goto end;
  70         }
  71
  72         /* Is enabled ? */
  73         ret = mi_lttng_writer_write_element_bool(writer, config_element_enabled, enabled);
  74         if (ret) {
  75                 goto end;
  76         }
  77
  78         /* Close session element */
  79         ret = mi_lttng_writer_close_element(writer);
  80
  81 end:
  82         return ret;
  83 }
  84
  85 /*
  86  * Start tracing for all trace of the session.
  87  */
  88 cmd_error_code stop_tracing(const char *session_name)
  89 {
  90         int ret;
  91
  92         ret = lttng_stop_tracing_no_wait(session_name);
  93         if (ret < 0) {
  94                 LTTNG_THROW_CTL(fmt::format("Failed to start session `{}`", session_name),
  95                                 static_cast<lttng_error_code>(-ret));
  96         }
  97
  98         if (!opt_no_wait) {
  99                 _MSG("Waiting for data availability");
 100                 fflush(stdout);
 101                 do {
 102                         ret = lttng_data_pending(session_name);
 103                         if (ret < 0) {
 104                                 /* Return the data available call error. */
 105                                 ERR_FMT("Failed to check pending data for session `{}` ({})",
 106                                         session_name,
 107                                         lttng_strerror(ret));
 108                                 return CMD_ERROR;
 109                         }
 110
 111                         /*
 112                          * Data sleep time before retrying (in usec). Don't sleep if the call
 113                          * returned value indicates availability.
 114                          */
 115                         if (ret) {
 116                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
 117                                 _MSG(".");
 118                                 fflush(stdout);
 119                         }
 120                 } while (ret != 0);
 121                 MSG("");
 122         }
 123
 124         print_session_stats(session_name);
 125         MSG("Tracing stopped for session `%s`", session_name);
 126         if (lttng_opt_mi) {
 127                 if (mi_print_session(session_name, 0)) {
 128                         return CMD_ERROR;
 129                 }
 130         }
 131
 132         return CMD_SUCCESS;
 133 }
 134
 135 cmd_error_code stop_tracing(const session_spec& spec) noexcept
 136 {
 137         bool had_warning = false;
 138         bool had_error = false;
 139         bool listing_failed = false;
 140
 141         const auto sessions = [&listing_failed, &spec]() -> session_list {
 142                 try {
 143                         return list_sessions(spec);
 144                 } catch (const lttng::ctl::error& ctl_exception) {
 145                         ERR_FMT("Failed to list sessions ({})",
 146                                 lttng_strerror(-ctl_exception.code()));
 147                         listing_failed = true;
 148                         return {};
 149                 }
 150         }();
 151
 152         if (!listing_failed && sessions.size() == 0 && spec.type == session_spec::type::NAME) {
 153                 ERR_FMT("Session `{}` not found", spec.value);
 154                 return CMD_ERROR;
 155         }
 156
 157         if (listing_failed) {
 158                 return CMD_FATAL;
 159         }
 160
 161         for (const auto& session : sessions) {
 162                 cmd_error_code sub_ret;
 163
 164                 try {
 165                         sub_ret = stop_tracing(session.name);
 166                 } catch (const lttng::ctl::error& ctl_exception) {
 167                         switch (ctl_exception.code()) {
 168                         case LTTNG_ERR_TRACE_ALREADY_STOPPED:
 169                                 WARN_FMT("Tracing already stopped for session `{}`", session.name);
 170                                 sub_ret = CMD_SUCCESS;
 171                                 break;
 172                         case LTTNG_ERR_NO_SESSION:
 173                                 if (spec.type != session_spec::type::NAME) {
 174                                         /* Session destroyed during command, ignore and carry-on. */
 175                                         sub_ret = CMD_SUCCESS;
 176                                         break;
 177                                 } else {
 178                                         sub_ret = CMD_ERROR;
 179                                         break;
 180                                 }
 181                         case LTTNG_ERR_NO_SESSIOND:
 182                                 /* Don't keep going on a fatal error. */
 183                                 return CMD_FATAL;
 184                         default:
 185                                 /* Generic error. */
 186                                 sub_ret = CMD_ERROR;
 187                                 ERR_FMT("Failed to stop session `{}` ({})",
 188                                         session.name,
 189                                         lttng_strerror(-ctl_exception.code()));
 190                                 break;
 191                         }
 192                 }
 193
 194                 /* Keep going, but report the most serious state. */
 195                 had_warning |= sub_ret == CMD_WARNING;
 196                 had_error |= sub_ret == CMD_ERROR;
 197         }
 198
 199         if (had_error) {
 200                 return CMD_ERROR;
 201         } else if (had_warning) {
 202                 return CMD_WARNING;
 203         } else {
 204                 return CMD_SUCCESS;
 205         }
 206 }
 207 } /* namespace */
 208
 209 /*
 210  *  cmd_stop
 211  *
 212  *  The 'stop <options>' first level command
 213  */
 214 int cmd_stop(int argc, const char **argv)
 215 {
 216         int opt;
 217         cmd_error_code command_ret = CMD_SUCCESS;
 218         bool success = true;
 219         static poptContext pc;
 220         const char *leftover = nullptr;
 221         struct session_spec session_spec = {
 222                 .type = session_spec::NAME,
 223                 .value = nullptr,
 224         };
 225
 226         pc = poptGetContext(nullptr, argc, argv, long_options, 0);
 227         poptReadDefaultConfig(pc, 0);
 228
 229         while ((opt = poptGetNextOpt(pc)) != -1) {
 230                 switch (opt) {
 231                 case OPT_HELP:
 232                 {
 233                         int ret;
 234
 235                         SHOW_HELP();
 236                         command_ret = static_cast<cmd_error_code>(ret);
 237                         goto end;
 238                 }
 239                 case OPT_LIST_OPTIONS:
 240                         list_cmd_options(stdout, long_options);
 241                         goto end;
 242                 case OPT_ENABLE_GLOB:
 243                         session_spec.type = session_spec::GLOB_PATTERN;
 244                         break;
 245                 case OPT_ALL:
 246                         session_spec.type = session_spec::ALL;
 247                         break;
 248                 default:
 249                         command_ret = CMD_UNDEFINED;
 250                         goto end;
 251                 }
 252         }
 253
 254         /* Mi check */
 255         if (lttng_opt_mi) {
 256                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 257                 if (!writer) {
 258                         command_ret = CMD_ERROR;
 259                         goto end;
 260                 }
 261
 262                 /* Open command element */
 263                 if (mi_lttng_writer_command_open(writer, mi_lttng_element_command_stop)) {
 264                         command_ret = CMD_ERROR;
 265                         goto end;
 266                 }
 267
 268                 /* Open output element */
 269                 if (mi_lttng_writer_open_element(writer, mi_lttng_element_command_output)) {
 270                         command_ret = CMD_ERROR;
 271                         goto end;
 272                 }
 273
 274                 /*
 275                  * Open sessions element
 276                  * For validation
 277                  */
 278                 if (mi_lttng_writer_open_element(writer, config_element_sessions)) {
 279                         command_ret = CMD_ERROR;
 280                         goto end;
 281                 }
 282         }
 283
 284         session_spec.value = poptGetArg(pc);
 285
 286         leftover = poptGetArg(pc);
 287         if (leftover) {
 288                 ERR("Unknown argument: %s", leftover);
 289                 command_ret = CMD_ERROR;
 290                 goto end;
 291         }
 292
 293         command_ret = stop_tracing(session_spec);
 294         if (command_ret) {
 295                 success = false;
 296         }
 297
 298         /* Mi closing */
 299         if (lttng_opt_mi) {
 300                 /* Close sessions and  output element */
 301                 if (mi_lttng_close_multi_element(writer, 2)) {
 302                         command_ret = CMD_ERROR;
 303                         goto end;
 304                 }
 305
 306                 /* Success ? */
 307                 if (mi_lttng_writer_write_element_bool(
 308                             writer, mi_lttng_element_command_success, success)) {
 309                         command_ret = CMD_ERROR;
 310                         goto end;
 311                 }
 312
 313                 /* Command element close */
 314                 if (mi_lttng_writer_command_close(writer)) {
 315                         command_ret = CMD_ERROR;
 316                         goto end;
 317                 }
 318         }
 319
 320 end:
 321         /* Mi clean-up */
 322         if (writer && mi_lttng_writer_destroy(writer)) {
 323                 command_ret = CMD_ERROR;
 324         }
 325
 326         poptFreeContext(pc);
 327         return command_ret;
 328 }