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 "../exception.hpp"
  11 #include "../utils.hpp"
  12
  13 #include <common/exception.hpp>
  14 #include <common/mi-lttng.hpp>
  15 #include <common/sessiond-comm/sessiond-comm.hpp>
  16
  17 #include <popt.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <sys/stat.h>
  22 #include <sys/types.h>
  23 #include <unistd.h>
  24
  25 enum {
  26         OPT_HELP = 1,
  27         OPT_LIST_OPTIONS,
  28         OPT_ENABLE_GLOB,
  29         OPT_ALL,
  30 };
  31
  32 namespace {
  33 int opt_no_wait;
  34 struct mi_writer *writer;
  35
  36 #ifdef LTTNG_EMBED_HELP
  37 const char help_msg[] =
  38 #include <lttng-stop.1.h>
  39         ;
  40 #endif
  41
  42 struct poptOption long_options[] = {
  43         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  44         { "help", 'h', POPT_ARG_NONE, nullptr, OPT_HELP, nullptr, nullptr },
  45         { "list-options", 0, POPT_ARG_NONE, nullptr, OPT_LIST_OPTIONS, nullptr, nullptr },
  46         { "no-wait", 'n', POPT_ARG_VAL, &opt_no_wait, 1, nullptr, nullptr },
  47         { "glob", 'g', POPT_ARG_NONE, nullptr, OPT_ENABLE_GLOB, nullptr, nullptr },
  48         { "all", 'a', POPT_ARG_NONE, nullptr, OPT_ALL, nullptr, nullptr },
  49         { nullptr, 0, 0, nullptr, 0, nullptr, nullptr }
  50 };
  51
  52 /*
  53  * Mi print of partial session
  54  */
  55 int mi_print_session(const char *session_name, int enabled)
  56 {
  57         int ret;
  58         LTTNG_ASSERT(writer);
  59         LTTNG_ASSERT(session_name);
  60
  61         /* Open session element */
  62         ret = mi_lttng_writer_open_element(writer, config_element_session);
  63         if (ret) {
  64                 goto end;
  65         }
  66
  67         /* Print session name element */
  68         ret = mi_lttng_writer_write_element_string(writer, config_element_name, session_name);
  69         if (ret) {
  70                 goto end;
  71         }
  72
  73         /* Is enabled ? */
  74         ret = mi_lttng_writer_write_element_bool(writer, config_element_enabled, enabled);
  75         if (ret) {
  76                 goto end;
  77         }
  78
  79         /* Close session element */
  80         ret = mi_lttng_writer_close_element(writer);
  81
  82 end:
  83         return ret;
  84 }
  85
  86 /*
  87  * Start tracing for all trace of the session.
  88  */
  89 cmd_error_code stop_tracing(const char *session_name)
  90 {
  91         int ret;
  92
  93         ret = lttng_stop_tracing_no_wait(session_name);
  94         if (ret < 0) {
  95                 LTTNG_THROW_CTL(lttng::format("Failed to start session `{}`", session_name),
  96                                 static_cast<lttng_error_code>(-ret));
  97         }
  98
  99         if (!opt_no_wait) {
 100                 _MSG("Waiting for data availability");
 101                 fflush(stdout);
 102                 do {
 103                         ret = lttng_data_pending(session_name);
 104                         if (ret < 0) {
 105                                 /* Return the data available call error. */
 106                                 ERR_FMT("Failed to check pending data for session `{}` ({})",
 107                                         session_name,
 108                                         lttng_strerror(ret));
 109                                 return CMD_ERROR;
 110                         }
 111
 112                         /*
 113                          * Data sleep time before retrying (in usec). Don't sleep if the call
 114                          * returned value indicates availability.
 115                          */
 116                         if (ret) {
 117                                 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US);
 118                                 _MSG(".");
 119                                 fflush(stdout);
 120                         }
 121                 } while (ret != 0);
 122                 MSG("");
 123         }
 124
 125         print_session_stats(session_name);
 126         MSG("Tracing stopped for session `%s`", session_name);
 127         if (lttng_opt_mi) {
 128                 if (mi_print_session(session_name, 0)) {
 129                         return CMD_ERROR;
 130                 }
 131         }
 132
 133         return CMD_SUCCESS;
 134 }
 135
 136 cmd_error_code stop_tracing(const lttng::cli::session_spec& spec)
 137 {
 138         bool had_warning = false;
 139         bool had_error = false;
 140         bool listing_failed = false;
 141
 142         const auto sessions = [&listing_failed, &spec]() -> lttng::cli::session_list {
 143                 try {
 144                         return list_sessions(spec);
 145                 } catch (const lttng::ctl::error& ctl_exception) {
 146                         ERR_FMT("Failed to list sessions ({})",
 147                                 lttng_strerror(-ctl_exception.code()));
 148                         listing_failed = true;
 149                         return {};
 150                 } catch (const lttng::cli::no_default_session_error& cli_exception) {
 151                         /*
 152                          * The retrieval of the default session name already logs
 153                          * an error when it fails. There is no value in printing
 154                          * anything about this exception.
 155                          */
 156                         listing_failed = true;
 157                         return {};
 158                 }
 159         }();
 160
 161         if (!listing_failed && sessions.size() == 0 &&
 162             spec.type_ == lttng::cli::session_spec::type::NAME) {
 163                 ERR_FMT("Session `{}` not found", spec.value);
 164                 return CMD_ERROR;
 165         }
 166
 167         if (listing_failed) {
 168                 return CMD_FATAL;
 169         }
 170
 171         for (const auto& session : sessions) {
 172                 cmd_error_code sub_ret;
 173
 174                 try {
 175                         sub_ret = stop_tracing(session.name);
 176                 } catch (const lttng::ctl::error& ctl_exception) {
 177                         switch (ctl_exception.code()) {
 178                         case LTTNG_ERR_TRACE_ALREADY_STOPPED:
 179                                 WARN_FMT("Tracing already stopped for session `{}`", session.name);
 180                                 sub_ret = CMD_SUCCESS;
 181                                 break;
 182                         case LTTNG_ERR_NO_SESSION:
 183                                 if (spec.type_ != lttng::cli::session_spec::type::NAME) {
 184                                         /* Session destroyed during command, ignore and carry-on. */
 185                                         sub_ret = CMD_SUCCESS;
 186                                         break;
 187                                 } else {
 188                                         sub_ret = CMD_ERROR;
 189                                         break;
 190                                 }
 191                         case LTTNG_ERR_NO_SESSIOND:
 192                                 /* Don't keep going on a fatal error. */
 193                                 return CMD_FATAL;
 194                         default:
 195                                 /* Generic error. */
 196                                 sub_ret = CMD_ERROR;
 197                                 ERR_FMT("Failed to stop session `{}` ({})",
 198                                         session.name,
 199                                         lttng_strerror(-ctl_exception.code()));
 200                                 break;
 201                         }
 202                 }
 203
 204                 /* Keep going, but report the most serious state. */
 205                 had_warning |= sub_ret == CMD_WARNING;
 206                 had_error |= sub_ret == CMD_ERROR;
 207         }
 208
 209         if (had_error) {
 210                 return CMD_ERROR;
 211         } else if (had_warning) {
 212                 return CMD_WARNING;
 213         } else {
 214                 return CMD_SUCCESS;
 215         }
 216 }
 217 } /* namespace */
 218
 219 /*
 220  *  cmd_stop
 221  *
 222  *  The 'stop <options>' first level command
 223  */
 224 int cmd_stop(int argc, const char **argv)
 225 {
 226         int opt;
 227         cmd_error_code command_ret = CMD_SUCCESS;
 228         bool success = true;
 229         static poptContext pc;
 230         const char *leftover = nullptr;
 231         lttng::cli::session_spec session_spec(lttng::cli::session_spec::type::NAME);
 232
 233         pc = poptGetContext(nullptr, argc, argv, long_options, 0);
 234         poptReadDefaultConfig(pc, 0);
 235
 236         while ((opt = poptGetNextOpt(pc)) != -1) {
 237                 switch (opt) {
 238                 case OPT_HELP:
 239                 {
 240                         int ret;
 241
 242                         SHOW_HELP();
 243                         command_ret = static_cast<cmd_error_code>(ret);
 244                         goto end;
 245                 }
 246                 case OPT_LIST_OPTIONS:
 247                         list_cmd_options(stdout, long_options);
 248                         goto end;
 249                 case OPT_ENABLE_GLOB:
 250                         session_spec.type_ = lttng::cli::session_spec::type::GLOB_PATTERN;
 251                         break;
 252                 case OPT_ALL:
 253                         session_spec.type_ = lttng::cli::session_spec::type::ALL;
 254                         break;
 255                 default:
 256                         command_ret = CMD_UNDEFINED;
 257                         goto end;
 258                 }
 259         }
 260
 261         /* Mi check */
 262         if (lttng_opt_mi) {
 263                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 264                 if (!writer) {
 265                         command_ret = CMD_ERROR;
 266                         goto end;
 267                 }
 268
 269                 /* Open command element */
 270                 if (mi_lttng_writer_command_open(writer, mi_lttng_element_command_stop)) {
 271                         command_ret = CMD_ERROR;
 272                         goto end;
 273                 }
 274
 275                 /* Open output element */
 276                 if (mi_lttng_writer_open_element(writer, mi_lttng_element_command_output)) {
 277                         command_ret = CMD_ERROR;
 278                         goto end;
 279                 }
 280
 281                 /*
 282                  * Open sessions element
 283                  * For validation
 284                  */
 285                 if (mi_lttng_writer_open_element(writer, config_element_sessions)) {
 286                         command_ret = CMD_ERROR;
 287                         goto end;
 288                 }
 289         }
 290
 291         session_spec.value = poptGetArg(pc);
 292
 293         leftover = poptGetArg(pc);
 294         if (leftover) {
 295                 ERR("Unknown argument: %s", leftover);
 296                 command_ret = CMD_ERROR;
 297                 goto end;
 298         }
 299
 300         command_ret = stop_tracing(session_spec);
 301         if (command_ret) {
 302                 success = false;
 303         }
 304
 305         /* Mi closing */
 306         if (lttng_opt_mi) {
 307                 /* Close sessions and  output element */
 308                 if (mi_lttng_close_multi_element(writer, 2)) {
 309                         command_ret = CMD_ERROR;
 310                         goto end;
 311                 }
 312
 313                 /* Success ? */
 314                 if (mi_lttng_writer_write_element_bool(
 315                             writer, mi_lttng_element_command_success, success)) {
 316                         command_ret = CMD_ERROR;
 317                         goto end;
 318                 }
 319
 320                 /* Command element close */
 321                 if (mi_lttng_writer_command_close(writer)) {
 322                         command_ret = CMD_ERROR;
 323                         goto end;
 324                 }
 325         }
 326
 327 end:
 328         /* Mi clean-up */
 329         if (writer && mi_lttng_writer_destroy(writer)) {
 330                 command_ret = CMD_ERROR;
 331         }
 332
 333         poptFreeContext(pc);
 334         return command_ret;
 335 }