src/common/mi-lttng.c

   1 /*
   2  * Copyright (C) 2014 - Jonathan Rajotte <jonathan.r.julien@gmail.com>
   3  *                    - Olivier Cotte <olivier.cotte@polymtl.ca>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License, version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 51
  16  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19
  20 #include <include/config.h>
  21 #include <common/config/config.h>
  22 #include <lttng/snapshot-internal.h>
  23 #include "mi-lttng.h"
  24
  25 #include <assert.h>
  26
  27 /* Strings related to command */
  28 const char * const mi_lttng_element_command = "command";
  29 const char * const mi_lttng_element_command_action = "snapshot_action";
  30 const char * const mi_lttng_element_command_add_context = "add-context";
  31 const char * const mi_lttng_element_command_calibrate = "calibrate";
  32 const char * const mi_lttng_element_command_create = "create";
  33 const char * const mi_lttng_element_command_destroy = "destroy";
  34 const char * const mi_lttng_element_command_disable_channel = "disable-channel";
  35 const char * const mi_lttng_element_command_disable_event = "disable-event";
  36 const char * const mi_lttng_element_command_enable_channels = "enable-channel";
  37 const char * const mi_lttng_element_command_enable_event = "enable-event";
  38 const char * const mi_lttng_element_command_list = "list";
  39 const char * const mi_lttng_element_command_load = "load";
  40 const char * const mi_lttng_element_command_name = "name";
  41 const char * const mi_lttng_element_command_output = "output";
  42 const char * const mi_lttng_element_command_save = "save";
  43 const char * const mi_lttng_element_command_set_session = "set-session";
  44 const char * const mi_lttng_element_command_snapshot = "snapshot";
  45 const char * const mi_lttng_element_command_snapshot_add = "add_snapshot";
  46 const char * const mi_lttng_element_command_snapshot_del = "del_snapshot";
  47 const char * const mi_lttng_element_command_snapshot_list = "list_snapshot";
  48 const char * const mi_lttng_element_command_snapshot_record = "record_snapshot";
  49 const char * const mi_lttng_element_command_start = "start";
  50 const char * const mi_lttng_element_command_stop = "stop";
  51 const char * const mi_lttng_element_command_success = "success";
  52 const char * const mi_lttng_element_command_version = "version";
  53
  54 /* Strings related to version command */
  55 const char * const mi_lttng_element_version = "version";
  56 const char * const mi_lttng_element_version_commit = "commit";
  57 const char * const mi_lttng_element_version_description = "description";
  58 const char * const mi_lttng_element_version_license = "license";
  59 const char * const mi_lttng_element_version_major = "major";
  60 const char * const mi_lttng_element_version_minor = "minor";
  61 const char * const mi_lttng_element_version_patch_level = "patchLevel";
  62 const char * const mi_lttng_element_version_str = "string";
  63 const char * const mi_lttng_element_version_web = "url";
  64
  65 /* String related to a lttng_event_field */
  66 const char * const mi_lttng_element_event_field = "event_field";
  67 const char * const mi_lttng_element_event_fields = "event_fields";
  68
  69 /* String related to lttng_event_context */
  70 const char * const mi_lttng_context_type_perf_counter = "PERF_COUNTER";
  71 const char * const mi_lttng_context_type_perf_cpu_counter = "PERF_CPU_COUNTER";
  72 const char * const mi_lttng_context_type_perf_thread_counter = "PERF_THREAD_COUNTER";
  73
  74 /* String related to lttng_event_perf_counter_ctx */
  75 const char * const mi_lttng_element_perf_counter_context = "perf_counter_context";
  76
  77 /* Strings related to pid */
  78 const char * const mi_lttng_element_pids = "pids";
  79 const char * const mi_lttng_element_pid = "pid";
  80 const char * const mi_lttng_element_pid_id = "id";
  81
  82 /* Strings related to save command */
  83 const char * const mi_lttng_element_save = "save";
  84
  85 /* Strings related to load command */
  86 const char * const mi_lttng_element_load = "load";
  87
  88 /* General elements of mi_lttng */
  89 const char * const mi_lttng_element_empty = "";
  90 const char * const mi_lttng_element_id = "id";
  91 const char * const mi_lttng_element_nowrite = "nowrite";
  92 const char * const mi_lttng_element_success = "success";
  93 const char * const mi_lttng_element_type_enum = "ENUM";
  94 const char * const mi_lttng_element_type_float = "FLOAT";
  95 const char * const mi_lttng_element_type_integer = "INTEGER";
  96 const char * const mi_lttng_element_type_other = "OTHER";
  97 const char * const mi_lttng_element_type_string = "STRING";
  98
  99 /* String related to loglevel */
 100 const char * const mi_lttng_loglevel_str_alert = "TRACE_ALERT";
 101 const char * const mi_lttng_loglevel_str_crit = "TRACE_CRIT";
 102 const char * const mi_lttng_loglevel_str_debug = "TRACE_DEBUG";
 103 const char * const mi_lttng_loglevel_str_debug_function = "TRACE_DEBUG_FUNCTION";
 104 const char * const mi_lttng_loglevel_str_debug_line = "TRACE_DEBUG_LINE";
 105 const char * const mi_lttng_loglevel_str_debug_module = "TRACE_DEBUG_MODULE";
 106 const char * const mi_lttng_loglevel_str_debug_process = "TRACE_DEBUG_PROCESS";
 107 const char * const mi_lttng_loglevel_str_debug_program = "TRACE_DEBUG_PROGRAM";
 108 const char * const mi_lttng_loglevel_str_debug_system = "TRACE_DEBUG_SYSTEM";
 109 const char * const mi_lttng_loglevel_str_debug_unit = "TRACE_DEBUG_UNIT";
 110 const char * const mi_lttng_loglevel_str_emerg = "TRACE_EMERG";
 111 const char * const mi_lttng_loglevel_str_err = "TRACE_ERR";
 112 const char * const mi_lttng_loglevel_str_info = "TRACE_INFO";
 113 const char * const mi_lttng_loglevel_str_notice = "TRACE_NOTICE";
 114 const char * const mi_lttng_loglevel_str_unknown = "UNKNOWN";
 115 const char * const mi_lttng_loglevel_str_warning = "TRACE_WARNING";
 116
 117 /* String related to loglevel JUL */
 118 const char * const mi_lttng_loglevel_str_jul_all = "JUL_ALL";
 119 const char * const mi_lttng_loglevel_str_jul_config = "JUL_CONFIG";
 120 const char * const mi_lttng_loglevel_str_jul_fine = "JUL_FINE";
 121 const char * const mi_lttng_loglevel_str_jul_finer = "JUL_FINER";
 122 const char * const mi_lttng_loglevel_str_jul_finest = "JUL_FINEST";
 123 const char * const mi_lttng_loglevel_str_jul_info = "JUL_INFO";
 124 const char * const mi_lttng_loglevel_str_jul_off = "JUL_OFF";
 125 const char * const mi_lttng_loglevel_str_jul_severe = "JUL_SEVERE";
 126 const char * const mi_lttng_loglevel_str_jul_warning = "JUL_WARNING";
 127
 128 /* String related to loglevel type */
 129 const char * const mi_lttng_loglevel_type_all = "ALL";
 130 const char * const mi_lttng_loglevel_type_range = "RANGE";
 131 const char * const mi_lttng_loglevel_type_single = "SINGLE";
 132 const char * const mi_lttng_loglevel_type_unknown = "UNKNOWN";
 133
 134 /* String related to lttng_calibrate */
 135 const char * const mi_lttng_element_calibrate = "calibrate";
 136 const char * const mi_lttng_element_calibrate_function = "FUNCTION";
 137
 138 /* String related to a lttng_snapshot_output */
 139 const char * const mi_lttng_element_snapshot_ctrl_url = "ctrl_url";
 140 const char * const mi_lttng_element_snapshot_data_url = "data_url";
 141 const char * const mi_lttng_element_snapshot_max_size = "max_size";
 142 const char * const mi_lttng_element_snapshot_n_ptr = "n_ptr";
 143 const char * const mi_lttng_element_snapshot_session_name = "session_name";
 144 const char * const mi_lttng_element_snapshots = "snapshots";
 145
 146 /* This is a merge of jul loglevel and regular loglevel
 147  * Those should never overlap by definition
 148  * (see struct lttng_event loglevel)
 149  */
 150 const char *mi_lttng_loglevel_string(int value)
 151 {
 152         switch (value) {
 153         case -1:
 154                 return mi_lttng_element_empty;
 155         case LTTNG_LOGLEVEL_EMERG:
 156                 return mi_lttng_loglevel_str_emerg;
 157         case LTTNG_LOGLEVEL_ALERT:
 158                 return mi_lttng_loglevel_str_alert;
 159         case LTTNG_LOGLEVEL_CRIT:
 160                 return mi_lttng_loglevel_str_crit;
 161         case LTTNG_LOGLEVEL_ERR:
 162                 return mi_lttng_loglevel_str_err;
 163         case LTTNG_LOGLEVEL_WARNING:
 164                 return mi_lttng_loglevel_str_warning;
 165         case LTTNG_LOGLEVEL_NOTICE:
 166                 return mi_lttng_loglevel_str_notice;
 167         case LTTNG_LOGLEVEL_INFO:
 168                 return mi_lttng_loglevel_str_info;
 169         case LTTNG_LOGLEVEL_DEBUG_SYSTEM:
 170                 return mi_lttng_loglevel_str_debug_system;
 171         case LTTNG_LOGLEVEL_DEBUG_PROGRAM:
 172                 return mi_lttng_loglevel_str_debug_program;
 173         case LTTNG_LOGLEVEL_DEBUG_PROCESS:
 174                 return mi_lttng_loglevel_str_debug_process;
 175         case LTTNG_LOGLEVEL_DEBUG_MODULE:
 176                 return mi_lttng_loglevel_str_debug_module;
 177         case LTTNG_LOGLEVEL_DEBUG_UNIT:
 178                 return mi_lttng_loglevel_str_debug_unit;
 179         case LTTNG_LOGLEVEL_DEBUG_FUNCTION:
 180                 return mi_lttng_loglevel_str_debug_function;
 181         case LTTNG_LOGLEVEL_DEBUG_LINE:
 182                 return mi_lttng_loglevel_str_debug_line;
 183         case LTTNG_LOGLEVEL_DEBUG:
 184                 return mi_lttng_loglevel_str_debug;
 185         case LTTNG_LOGLEVEL_JUL_OFF:
 186                 return mi_lttng_loglevel_str_jul_off;
 187         case LTTNG_LOGLEVEL_JUL_SEVERE:
 188                 return mi_lttng_loglevel_str_jul_severe;
 189         case LTTNG_LOGLEVEL_JUL_WARNING:
 190                 return mi_lttng_loglevel_str_jul_warning;
 191         case LTTNG_LOGLEVEL_JUL_INFO:
 192                 return mi_lttng_loglevel_str_jul_info;
 193         case LTTNG_LOGLEVEL_JUL_CONFIG:
 194                 return mi_lttng_loglevel_str_jul_config;
 195         case LTTNG_LOGLEVEL_JUL_FINE:
 196                 return mi_lttng_loglevel_str_jul_fine;
 197         case LTTNG_LOGLEVEL_JUL_FINER:
 198                 return mi_lttng_loglevel_str_jul_finer;
 199         case LTTNG_LOGLEVEL_JUL_FINEST:
 200                 return mi_lttng_loglevel_str_jul_finest;
 201         case LTTNG_LOGLEVEL_JUL_ALL:
 202                 return mi_lttng_loglevel_str_jul_all;
 203         default:
 204                 return mi_lttng_loglevel_str_unknown;
 205         }
 206 }
 207
 208 const char *mi_lttng_logleveltype_string(enum lttng_loglevel_type value)
 209 {
 210         switch (value) {
 211         case LTTNG_EVENT_LOGLEVEL_ALL:
 212                 return mi_lttng_loglevel_type_all;
 213         case LTTNG_EVENT_LOGLEVEL_RANGE:
 214                 return mi_lttng_loglevel_type_range;
 215         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 216                 return mi_lttng_loglevel_type_single;
 217         default:
 218                 return mi_lttng_loglevel_type_unknown;
 219         }
 220 }
 221
 222 const char *mi_lttng_eventtype_string(enum lttng_event_type value)
 223 {
 224         switch (value) {
 225         case LTTNG_EVENT_ALL:
 226                 return config_event_type_all;
 227         case LTTNG_EVENT_TRACEPOINT:
 228                 return config_event_type_tracepoint;
 229         case LTTNG_EVENT_PROBE:
 230                 return config_event_type_probe;
 231         case LTTNG_EVENT_FUNCTION:
 232                 return config_event_type_function;
 233         case LTTNG_EVENT_FUNCTION_ENTRY:
 234                 return config_event_type_function_entry;
 235         case LTTNG_EVENT_SYSCALL:
 236                 return config_event_type_syscall;
 237         case LTTNG_EVENT_NOOP:
 238                 return config_event_type_noop;
 239         default:
 240                 return mi_lttng_element_empty;
 241         }
 242 }
 243
 244 const char *mi_lttng_event_contexttype_string(enum lttng_event_context_type val)
 245 {
 246         switch (val) {
 247         case LTTNG_EVENT_CONTEXT_PID:
 248                 return config_event_context_pid;
 249         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
 250                 return mi_lttng_context_type_perf_counter;
 251         case LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER:
 252                 return mi_lttng_context_type_perf_thread_counter;
 253         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
 254                 return mi_lttng_context_type_perf_cpu_counter;
 255         case LTTNG_EVENT_CONTEXT_PROCNAME:
 256                 return config_event_context_procname;
 257         case LTTNG_EVENT_CONTEXT_PRIO:
 258                 return config_event_context_prio;
 259         case LTTNG_EVENT_CONTEXT_NICE:
 260                 return config_event_context_nice;
 261         case LTTNG_EVENT_CONTEXT_VPID:
 262                 return config_event_context_vpid;
 263         case LTTNG_EVENT_CONTEXT_TID:
 264                 return config_event_context_tid;
 265         case LTTNG_EVENT_CONTEXT_VTID:
 266                 return config_event_context_vtid;
 267         case LTTNG_EVENT_CONTEXT_PPID:
 268                 return config_event_context_ppid;
 269         case LTTNG_EVENT_CONTEXT_VPPID:
 270                 return config_event_context_vppid;
 271         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 272                 return config_event_context_pthread_id;
 273         case LTTNG_EVENT_CONTEXT_HOSTNAME:
 274                 return config_event_context_hostname;
 275         case LTTNG_EVENT_CONTEXT_IP:
 276                 return config_event_context_ip;
 277         default:
 278                 return NULL;
 279         }
 280 }
 281
 282 const char *mi_lttng_eventfieldtype_string(enum lttng_event_field_type val)
 283 {
 284         switch (val) {
 285         case(LTTNG_EVENT_FIELD_INTEGER):
 286                 return mi_lttng_element_type_integer;
 287         case(LTTNG_EVENT_FIELD_ENUM):
 288                 return mi_lttng_element_type_enum;
 289         case(LTTNG_EVENT_FIELD_FLOAT):
 290                 return mi_lttng_element_type_float;
 291         case(LTTNG_EVENT_FIELD_STRING):
 292                 return mi_lttng_element_type_string;
 293         default:
 294                 return mi_lttng_element_type_other;
 295         }
 296 }
 297
 298 const char *mi_lttng_domaintype_string(enum lttng_domain_type value)
 299 {
 300         /* Note: This is a *duplicate* of get_domain_str from bin/lttng/utils.c */
 301         switch (value) {
 302         case LTTNG_DOMAIN_KERNEL:
 303                 return config_domain_type_kernel;
 304         case LTTNG_DOMAIN_UST:
 305                 return config_domain_type_ust;
 306         case LTTNG_DOMAIN_JUL:
 307                 return config_domain_type_jul;
 308         case LTTNG_DOMAIN_LOG4J:
 309                 return config_domain_type_log4j;
 310         default:
 311                 /* Should not have an unknown domain */
 312                 assert(0);
 313         }
 314 }
 315
 316 const char *mi_lttng_buffertype_string(enum lttng_buffer_type value)
 317 {
 318         switch (value) {
 319         case LTTNG_BUFFER_PER_PID:
 320                 return config_buffer_type_per_pid;
 321         case LTTNG_BUFFER_PER_UID:
 322                 return config_buffer_type_per_uid;
 323         case LTTNG_BUFFER_GLOBAL:
 324                 return config_buffer_type_global;
 325         default:
 326                 /* Should not have an unknow buffer type */
 327                 assert(0);
 328         }
 329 }
 330
 331 const char *mi_lttng_calibratetype_string(enum lttng_calibrate_type val)
 332 {
 333         const char *ret;
 334
 335         switch (val) {
 336         case LTTNG_CALIBRATE_FUNCTION:
 337                 ret = mi_lttng_element_calibrate_function;
 338                 break;
 339         default:
 340                 ret = mi_lttng_element_empty;
 341                 break;
 342         }
 343         return ret;
 344 }
 345
 346 LTTNG_HIDDEN
 347 struct mi_writer *mi_lttng_writer_create(int fd_output, int mi_output_type)
 348 {
 349         struct mi_writer *mi_writer;
 350
 351         mi_writer = zmalloc(sizeof(struct mi_writer));
 352         if (!mi_writer) {
 353                 PERROR("zmalloc mi_writer_create");
 354                 goto end;
 355         }
 356         if (mi_output_type == LTTNG_MI_XML) {
 357                 mi_writer->writer = config_writer_create(fd_output, 0);
 358                 if (!mi_writer->writer) {
 359                         goto err_destroy;
 360                 }
 361                 mi_writer->type = LTTNG_MI_XML;
 362         } else {
 363                 goto err_destroy;
 364         }
 365
 366 end:
 367         return mi_writer;
 368
 369 err_destroy:
 370         free(mi_writer);
 371         return NULL;
 372 }
 373
 374 LTTNG_HIDDEN
 375 int mi_lttng_writer_destroy(struct mi_writer *writer)
 376 {
 377         int ret;
 378
 379         if (!writer) {
 380                 ret = -EINVAL;
 381                 goto end;
 382         }
 383
 384         ret = config_writer_destroy(writer->writer);
 385         if (ret < 0) {
 386                 goto end;
 387         }
 388
 389         free(writer);
 390 end:
 391         return ret;
 392 }
 393
 394 LTTNG_HIDDEN
 395 int mi_lttng_writer_command_open(struct mi_writer *writer, const char *command)
 396 {
 397         int ret;
 398
 399         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_command);
 400         if (ret) {
 401                 goto end;
 402         }
 403         ret = mi_lttng_writer_write_element_string(writer,
 404                         mi_lttng_element_command_name, command);
 405 end:
 406         return ret;
 407 }
 408
 409 LTTNG_HIDDEN
 410 int mi_lttng_writer_command_close(struct mi_writer *writer)
 411 {
 412         return mi_lttng_writer_close_element(writer);
 413 }
 414
 415 LTTNG_HIDDEN
 416 int mi_lttng_writer_open_element(struct mi_writer *writer,
 417                 const char *element_name)
 418 {
 419         return config_writer_open_element(writer->writer, element_name);
 420 }
 421
 422 LTTNG_HIDDEN
 423 int mi_lttng_writer_close_element(struct mi_writer *writer)
 424 {
 425         return config_writer_close_element(writer->writer);
 426 }
 427
 428 LTTNG_HIDDEN
 429 int mi_lttng_close_multi_element(struct mi_writer *writer,
 430                 unsigned int nb_element)
 431 {
 432         int ret, i;
 433
 434         if (nb_element < 1) {
 435                 ret = 0;
 436                 goto end;
 437         }
 438         for (i = 0; i < nb_element; i++) {
 439                 ret = mi_lttng_writer_close_element(writer);
 440                 if (ret) {
 441                         goto end;
 442                 }
 443         }
 444 end:
 445         return ret;
 446 }
 447
 448 LTTNG_HIDDEN
 449 int mi_lttng_writer_write_element_unsigned_int(struct mi_writer *writer,
 450                 const char *element_name, uint64_t value)
 451 {
 452         return config_writer_write_element_unsigned_int(writer->writer,
 453                         element_name, value);
 454 }
 455
 456 LTTNG_HIDDEN
 457 int mi_lttng_writer_write_element_signed_int(struct mi_writer *writer,
 458                 const char *element_name, int64_t value)
 459 {
 460         return config_writer_write_element_signed_int(writer->writer,
 461                         element_name, value);
 462 }
 463
 464 LTTNG_HIDDEN
 465 int mi_lttng_writer_write_element_bool(struct mi_writer *writer,
 466                 const char *element_name, int value)
 467 {
 468         return config_writer_write_element_bool(writer->writer,
 469                         element_name, value);
 470 }
 471
 472 LTTNG_HIDDEN
 473 int mi_lttng_writer_write_element_string(struct mi_writer *writer,
 474                 const char *element_name, const char *value)
 475 {
 476         return config_writer_write_element_string(writer->writer,
 477                         element_name, value);
 478 }
 479
 480 LTTNG_HIDDEN
 481 int mi_lttng_version(struct mi_writer *writer, struct mi_lttng_version *version,
 482         const char *lttng_description, const char *lttng_license)
 483 {
 484         int ret;
 485
 486         /* Open version */
 487         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_version);
 488         if (ret) {
 489                 goto end;
 490         }
 491
 492         /* Version string (contain info like rc etc.) */
 493         ret = mi_lttng_writer_write_element_string(writer,
 494                         mi_lttng_element_version_str, version->version);
 495         if (ret) {
 496                 goto end;
 497         }
 498
 499         /* Major version number */
 500         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 501                         mi_lttng_element_version_major, version->version_major);
 502         if (ret) {
 503                 goto end;
 504         }
 505
 506         /* Minor version number */
 507         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 508                         mi_lttng_element_version_minor, version->version_minor);
 509         if (ret) {
 510                 goto end;
 511         }
 512
 513         /* Commit version number */
 514         ret = mi_lttng_writer_write_element_string(writer,
 515                         mi_lttng_element_version_commit, version->version_commit);
 516         if (ret) {
 517                 goto end;
 518         }
 519
 520         /* Patch number */
 521         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 522                         mi_lttng_element_version_patch_level, version->version_patchlevel);
 523         if (ret) {
 524                 goto end;
 525         }
 526
 527         /* Name of the version */
 528         ret = mi_lttng_writer_write_element_string(writer,
 529                         config_element_name, version->version_name);
 530         if (ret) {
 531                 goto end;
 532         }
 533
 534         /* Description mostly related to beer... */
 535         ret = mi_lttng_writer_write_element_string(writer,
 536                         mi_lttng_element_version_description, lttng_description);
 537         if (ret) {
 538                 goto end;
 539         }
 540
 541         /* url */
 542         ret = mi_lttng_writer_write_element_string(writer,
 543                         mi_lttng_element_version_web, version->package_url);
 544         if (ret) {
 545                 goto end;
 546         }
 547
 548         /* License: free as in free beer...no...*speech* */
 549         ret = mi_lttng_writer_write_element_string(writer,
 550                         mi_lttng_element_version_license, lttng_license);
 551         if (ret) {
 552                 goto end;
 553         }
 554
 555         /* Close version element */
 556         ret = mi_lttng_writer_close_element(writer);
 557
 558 end:
 559         return ret;
 560 }
 561
 562 LTTNG_HIDDEN
 563 int mi_lttng_sessions_open(struct mi_writer *writer)
 564 {
 565         return mi_lttng_writer_open_element(writer, config_element_sessions);
 566 }
 567
 568 LTTNG_HIDDEN
 569 int mi_lttng_session(struct mi_writer *writer,
 570                 struct lttng_session *session, int is_open)
 571 {
 572         int ret;
 573
 574         assert(session);
 575
 576         /* Open sessions element */
 577         ret = mi_lttng_writer_open_element(writer,
 578                         config_element_session);
 579         if (ret) {
 580                 goto end;
 581         }
 582
 583         /* Name of the session */
 584         ret = mi_lttng_writer_write_element_string(writer,
 585                         config_element_name, session->name);
 586         if (ret) {
 587                 goto end;
 588         }
 589
 590         /* Path */
 591         ret = mi_lttng_writer_write_element_string(writer,
 592                         config_element_path, session->path);
 593         if (ret) {
 594                 goto end;
 595         }
 596
 597         /* Enabled ? */
 598         ret = mi_lttng_writer_write_element_bool(writer,
 599                         config_element_enabled, session->enabled);
 600         if (ret) {
 601                 goto end;
 602         }
 603
 604         /* Snapshot mode */
 605         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 606                         config_element_snapshot_mode, session->snapshot_mode);
 607         if (ret) {
 608                 goto end;
 609         }
 610
 611         /* Live timer interval in usec */
 612         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 613                         config_element_live_timer_interval,
 614                         session->live_timer_interval);
 615         if (ret) {
 616                 goto end;
 617         }
 618
 619         if (!is_open) {
 620                 /* Closing session element */
 621                 ret = mi_lttng_writer_close_element(writer);
 622         }
 623 end:
 624         return ret;
 625
 626 }
 627
 628 LTTNG_HIDDEN
 629 int mi_lttng_domains_open(struct mi_writer *writer)
 630 {
 631         return mi_lttng_writer_open_element(writer, config_element_domains);
 632 }
 633
 634 LTTNG_HIDDEN
 635 int mi_lttng_domain(struct mi_writer *writer,
 636                 struct lttng_domain *domain, int is_open)
 637 {
 638         int ret = 0;
 639         const char *str_domain;
 640         const char *str_buffer;
 641
 642         assert(domain);
 643
 644         /* Open domain element */
 645         ret = mi_lttng_writer_open_element(writer, config_element_domain);
 646         if (ret) {
 647                 goto end;
 648         }
 649
 650         /* Domain Type */
 651         str_domain = mi_lttng_domaintype_string(domain->type);
 652         ret = mi_lttng_writer_write_element_string(writer, config_element_type,
 653                         str_domain);
 654         if (ret) {
 655                 goto end;
 656         }
 657
 658         /* Buffer Type */
 659         str_buffer= mi_lttng_buffertype_string(domain->buf_type);
 660         ret = mi_lttng_writer_write_element_string(writer,
 661                         config_element_buffer_type, str_buffer);
 662         if (ret) {
 663                 goto end;
 664         }
 665
 666         /* TODO: union  attr
 667          * This union is not currently used and was added for
 668          * future ust domain support.
 669          * Date: 25-06-2014
 670          * */
 671
 672         if (!is_open) {
 673                 /* Closing domain element */
 674                 ret = mi_lttng_writer_close_element(writer);
 675         }
 676
 677 end:
 678         return ret;
 679
 680 }
 681
 682 LTTNG_HIDDEN
 683 int mi_lttng_channels_open(struct mi_writer *writer)
 684 {
 685         return mi_lttng_writer_open_element(writer, config_element_channels);
 686 }
 687
 688 LTTNG_HIDDEN
 689 int mi_lttng_channel(struct mi_writer *writer,
 690                 struct lttng_channel *channel, int is_open)
 691 {
 692         int ret = 0;
 693
 694         assert(channel);
 695
 696         /* Opening channel element */
 697         ret = mi_lttng_writer_open_element(writer, config_element_channel);
 698         if (ret) {
 699                 goto end;
 700         }
 701
 702         /* Name */
 703         ret = mi_lttng_writer_write_element_string(writer, config_element_name,
 704                         channel->name);
 705         if (ret) {
 706                 goto end;
 707         }
 708
 709         /* Enabled ? */
 710         ret = mi_lttng_writer_write_element_bool(writer,
 711                         config_element_enabled, channel->enabled);
 712         if (ret) {
 713                 goto end;
 714         }
 715
 716         /* Attribute */
 717         ret = mi_lttng_channel_attr(writer, &channel->attr);
 718         if (ret) {
 719                 goto end;
 720         }
 721
 722         if (!is_open) {
 723                 /* Closing channel element */
 724                 ret = mi_lttng_writer_close_element(writer);
 725                 if (ret) {
 726                         goto end;
 727                 }
 728         }
 729 end:
 730         return ret;
 731 }
 732
 733 LTTNG_HIDDEN
 734 int mi_lttng_channel_attr(struct mi_writer *writer,
 735                 struct lttng_channel_attr *attr)
 736 {
 737         int ret = 0;
 738
 739         assert(attr);
 740
 741         /* Opening Attributes */
 742         ret = mi_lttng_writer_open_element(writer, config_element_attributes);
 743         if (ret) {
 744                 goto end;
 745         }
 746
 747         /* Overwrite */
 748         ret = mi_lttng_writer_write_element_string(writer,
 749                 config_element_overwrite_mode,
 750                 attr->overwrite ? config_overwrite_mode_overwrite :
 751                         config_overwrite_mode_discard);
 752         if (ret) {
 753                 goto end;
 754         }
 755
 756         /* Sub buffer size in byte */
 757         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 758                 config_element_subbuf_size, attr->subbuf_size);
 759         if (ret) {
 760                 goto end;
 761         }
 762
 763         /* Number of subbuffer (power of two) */
 764         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 765                 config_element_num_subbuf,
 766                 attr->num_subbuf);
 767         if (ret) {
 768                 goto end;
 769         }
 770
 771         /* Switch timer interval in usec */
 772         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 773                 config_element_switch_timer_interval,
 774                 attr->switch_timer_interval);
 775         if (ret) {
 776                 goto end;
 777         }
 778
 779         /* Read timer interval in usec */
 780         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 781                 config_element_read_timer_interval,
 782                 attr->read_timer_interval);
 783         if (ret) {
 784                 goto end;
 785         }
 786
 787         /* Event output */
 788         ret = mi_lttng_writer_write_element_string(writer,
 789                 config_element_output_type,
 790                 attr->output == LTTNG_EVENT_SPLICE ?
 791                 config_output_type_splice : config_output_type_mmap);
 792         if (ret) {
 793                 goto end;
 794         }
 795
 796         /* Tracefile size in bytes */
 797         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 798                 config_element_tracefile_size, attr->tracefile_size);
 799         if (ret) {
 800                 goto end;
 801         }
 802
 803         /* Count of tracefiles */
 804         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 805                 config_element_tracefile_count,
 806                 attr->tracefile_count);
 807         if (ret) {
 808                 goto end;
 809         }
 810
 811         /* Live timer interval in usec*/
 812         ret = mi_lttng_writer_write_element_unsigned_int(writer,
 813                 config_element_live_timer_interval,
 814                 attr->live_timer_interval);
 815         if (ret) {
 816                 goto end;
 817         }
 818
 819         /* Closing attributes */
 820         ret = mi_lttng_writer_close_element(writer);
 821         if (ret) {
 822                 goto end;
 823         }
 824 end:
 825         return ret;
 826
 827 }
 828
 829 LTTNG_HIDDEN
 830 int mi_lttng_event_common_attributes(struct mi_writer *writer,
 831                 struct lttng_event *event)
 832 {
 833         int ret;
 834
 835         /* Open event element */
 836         ret = mi_lttng_writer_open_element(writer, config_element_event);
 837         if (ret) {
 838                 goto end;
 839         }
 840
 841         /* Event name */
 842         ret = mi_lttng_writer_write_element_string(writer,
 843                         config_element_name, event->name);
 844         if (ret) {
 845                 goto end;
 846         }
 847
 848         /* Event type */
 849         ret = mi_lttng_writer_write_element_string(writer,
 850                         config_element_type, mi_lttng_eventtype_string(event->type));
 851         if (ret) {
 852                 goto end;
 853         }
 854
 855         /* Is event enabled */
 856         ret = mi_lttng_writer_write_element_bool(writer,
 857                         config_element_enabled, event->enabled);
 858         if (ret) {
 859                 goto end;
 860         }
 861
 862         /* Event filter enabled? */
 863         ret = mi_lttng_writer_write_element_bool(writer,
 864                         config_element_filter, event->filter);
 865
 866 end:
 867         return ret;
 868 }
 869
 870 LTTNG_HIDDEN
 871 int mi_lttng_event_tracepoint_loglevel(struct mi_writer *writer,
 872                 struct lttng_event *event)
 873 {
 874         int ret;
 875
 876         /* Event loglevel */
 877         ret = mi_lttng_writer_write_element_string(writer,
 878                         config_element_loglevel, mi_lttng_loglevel_string(event->loglevel));
 879         if (ret) {
 880                 goto end;
 881         }
 882
 883         /* Log level type */
 884         ret = mi_lttng_writer_write_element_string(writer,
 885                         config_element_loglevel_type,
 886                         mi_lttng_logleveltype_string(event->loglevel_type));
 887         if (ret) {
 888                 goto end;
 889         }
 890
 891         /* event exclusion filter */
 892         ret = mi_lttng_writer_write_element_bool(writer,
 893                         config_element_exclusion, event->exclusion);
 894         if (ret) {
 895                 goto end;
 896         }
 897
 898 end:
 899         return ret;
 900 }
 901
 902 LTTNG_HIDDEN
 903 int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer *writer,
 904                 struct lttng_event *event)
 905 {
 906         /* event exclusion filter */
 907         return mi_lttng_writer_write_element_bool(writer,
 908                         config_element_exclusion, event->exclusion);
 909 }
 910
 911 LTTNG_HIDDEN
 912 int mi_lttng_event_function_probe(struct mi_writer *writer,
 913                 struct lttng_event *event)
 914 {
 915         int ret;
 916
 917         if (event->attr.probe.addr != 0) {
 918                 /* event probe address */
 919                 ret = mi_lttng_writer_write_element_unsigned_int(writer,
 920                                 config_element_address, event->attr.probe.addr);
 921                 if (ret) {
 922                         goto end;
 923                 }
 924         } else {
 925                 /* event probe offset */
 926                 ret = mi_lttng_writer_write_element_unsigned_int(writer,
 927                                 config_element_offset, event->attr.probe.offset);
 928                 if (ret) {
 929                         goto end;
 930                 }
 931
 932                 /* event probe symbol_name */
 933                 ret = mi_lttng_writer_write_element_string(writer,
 934                                 config_element_symbol_name, event->attr.probe.symbol_name);
 935                 if (ret) {
 936                         goto end;
 937                 }
 938         }
 939 end:
 940         return ret;
 941 }
 942
 943 LTTNG_HIDDEN
 944 int mi_lttng_event_function_entry(struct mi_writer *writer,
 945                 struct lttng_event *event)
 946 {
 947         /* event probe symbol_name */
 948         return mi_lttng_writer_write_element_string(writer,
 949                         config_element_symbol_name, event->attr.ftrace.symbol_name);
 950 }
 951
 952 LTTNG_HIDDEN
 953 int mi_lttng_events_open(struct mi_writer *writer)
 954 {
 955         return mi_lttng_writer_open_element(writer, config_element_events);
 956 }
 957
 958 LTTNG_HIDDEN
 959 int mi_lttng_event(struct mi_writer *writer,
 960                 struct lttng_event *event, int is_open)
 961 {
 962         int ret;
 963
 964         ret = mi_lttng_event_common_attributes(writer, event);
 965         if (ret) {
 966                 goto end;
 967         }
 968
 969         switch (event->type) {
 970         case LTTNG_EVENT_TRACEPOINT:
 971         {
 972                 if (event->loglevel != -1) {
 973                         ret = mi_lttng_event_tracepoint_loglevel(writer, event);
 974                 } else {
 975                         ret = mi_lttng_event_tracepoint_no_loglevel(writer, event);
 976                 }
 977                 break;
 978         }
 979         case LTTNG_EVENT_PROBE:
 980                 ret = mi_lttng_event_function_probe(writer, event);
 981                 break;
 982         case LTTNG_EVENT_FUNCTION_ENTRY:
 983                 ret = mi_lttng_event_function_entry(writer, event);
 984                 break;
 985         case LTTNG_EVENT_ALL:
 986                 /* Fallthrough */
 987         default:
 988                 break;
 989         }
 990
 991         if (!is_open) {
 992                 ret = mi_lttng_writer_close_element(writer);
 993         }
 994
 995 end:
 996         return ret;
 997 }
 998
 999 LTTNG_HIDDEN
1000 int mi_lttng_pids_open(struct mi_writer *writer)
1001 {
1002         return mi_lttng_writer_open_element(writer, mi_lttng_element_pids);
1003 }
1004
1005 LTTNG_HIDDEN
1006 int mi_lttng_pid(struct mi_writer *writer, pid_t pid , const char *cmdline,
1007                 int is_open)
1008 {
1009         int ret;
1010
1011         /* Open element pid */
1012         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_pid);
1013         if (ret) {
1014                 goto end;
1015         }
1016
1017         /* Writing pid number */
1018         ret = mi_lttng_writer_write_element_signed_int(writer,
1019                         mi_lttng_element_pid_id, (int)pid);
1020         if (ret) {
1021                 goto end;
1022         }
1023
1024         /* Writing name of the process */
1025         ret = mi_lttng_writer_write_element_string(writer, config_element_name,
1026                         cmdline);
1027         if (ret) {
1028                 goto end;
1029         }
1030
1031         if (!is_open) {
1032                 /* Closing Pid */
1033                 ret = mi_lttng_writer_close_element(writer);
1034         }
1035
1036 end:
1037         return ret;
1038 }
1039
1040 LTTNG_HIDDEN
1041 int mi_lttng_event_fields_open(struct mi_writer *writer)
1042 {
1043         return mi_lttng_writer_open_element(writer, mi_lttng_element_event_fields);
1044 }
1045
1046 LTTNG_HIDDEN
1047 int mi_lttng_event_field(struct mi_writer *writer,
1048                 struct lttng_event_field *field)
1049 {
1050         int ret;
1051
1052         if (!field->field_name[0]) {
1053                 ret = 0;
1054                 goto end;
1055         }
1056
1057         /* Open field */
1058         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_event_field);
1059         if (ret) {
1060                 goto end;
1061         }
1062
1063         if (!field->field_name[0]) {
1064                 goto close;
1065         }
1066
1067         /* Name */
1068         ret = mi_lttng_writer_write_element_string(writer, config_element_name,
1069                         field->field_name);
1070         if (ret) {
1071                 goto end;
1072         }
1073
1074         /* Type */
1075         ret = mi_lttng_writer_write_element_string(writer, config_element_type,
1076                         mi_lttng_eventfieldtype_string(field->type));
1077         if (ret) {
1078                 goto end;
1079         }
1080
1081         /* nowrite  */
1082         ret = mi_lttng_writer_write_element_signed_int(writer,
1083                         mi_lttng_element_nowrite, field->nowrite);
1084         if (ret) {
1085                 goto end;
1086         }
1087
1088 close:
1089         /* Close field element */
1090         ret = mi_lttng_writer_close_element(writer);
1091
1092 end:
1093         return ret;
1094 }
1095
1096 LTTNG_HIDDEN
1097 int mi_lttng_calibrate(struct mi_writer *writer,
1098                 struct lttng_calibrate *calibrate)
1099 {
1100         int ret;
1101
1102         /* Open calibrate element */
1103         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_calibrate);
1104         if (ret) {
1105                 goto end;
1106         }
1107
1108         /* Calibration type */
1109         ret = mi_lttng_writer_write_element_string(writer, config_element_type,
1110                         mi_lttng_calibratetype_string(calibrate->type));
1111         if (ret) {
1112                 goto end;
1113         }
1114
1115         /* Closing calibrate element */
1116         ret = mi_lttng_writer_close_element(writer);
1117 end:
1118         return ret;
1119 }
1120 LTTNG_HIDDEN
1121 int mi_lttng_context(struct mi_writer *writer,
1122                 struct lttng_event_context *context, int is_open)
1123 {
1124         int ret;
1125         const char *type_string;
1126         struct lttng_event_perf_counter_ctx *perf_context;
1127         /* Open context */
1128         ret = mi_lttng_writer_open_element(writer , config_element_context);
1129         if (ret) {
1130                 goto end;
1131         }
1132
1133         type_string = mi_lttng_event_contexttype_string(context->ctx);
1134         if (!type_string) {
1135                 ret = -LTTNG_ERR_INVALID;
1136                 goto end;
1137         }
1138
1139         /* Print context type */
1140         ret = mi_lttng_writer_write_element_string(writer, config_element_type,
1141                         type_string);
1142
1143         /* Special case for PERF_*_COUNTER
1144          * print the lttng_event_perf_counter_ctx*/
1145         switch (context->ctx) {
1146         case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
1147         case LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER:
1148         case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
1149                 perf_context = &context->u.perf_counter;
1150                 ret =  mi_lttng_perf_counter_context(writer, perf_context);
1151                 if (ret) {
1152                         goto end;
1153                 }
1154                 break;
1155         default:
1156                 break;
1157         }
1158
1159         /* Close context */
1160         if (!is_open) {
1161                 ret = mi_lttng_writer_close_element(writer);
1162         }
1163
1164 end:
1165         return ret;
1166 }
1167
1168 LTTNG_HIDDEN
1169 int mi_lttng_perf_counter_context(struct mi_writer *writer,
1170                 struct lttng_event_perf_counter_ctx  *perf_context)
1171 {
1172         int ret;
1173
1174         /* Open perf_counter_context */
1175         ret = mi_lttng_writer_open_element(writer,
1176                         mi_lttng_element_perf_counter_context);
1177         if (ret) {
1178                 goto end;
1179         }
1180
1181         /* Type */
1182         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1183                         config_element_type, perf_context->type);
1184         if (ret) {
1185                 goto end;
1186         }
1187
1188         /* Config */
1189         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1190                         config_element_config, perf_context->config);
1191         if (ret) {
1192                 goto end;
1193         }
1194
1195         /* Name of the perf counter */
1196         ret = mi_lttng_writer_write_element_string(writer,
1197                         config_element_name, perf_context->name);
1198         if (ret) {
1199                 goto end;
1200         }
1201
1202         /* Close perf_counter_context */
1203         ret = mi_lttng_writer_close_element(writer);
1204 end:
1205         return ret;
1206 }
1207
1208 LTTNG_HIDDEN
1209 int mi_lttng_snapshot_output_session_name(struct mi_writer *writer,
1210                 const char *session_name)
1211 {
1212         int ret;
1213
1214         /* Open session element */
1215         ret = mi_lttng_writer_open_element(writer, config_element_session);
1216         if (ret) {
1217                 goto end;
1218         }
1219
1220         /* Snapshot output list for current session name */
1221         ret = mi_lttng_writer_write_element_string(writer, config_element_name,
1222                         session_name);
1223
1224         /* Open element snapshots (sequence one snapshot) */
1225         ret = mi_lttng_writer_open_element(writer, mi_lttng_element_snapshots);
1226         if (ret) {
1227                 goto end;
1228         }
1229
1230 end:
1231         return ret;
1232 }
1233
1234 LTTNG_HIDDEN
1235 int mi_lttng_snapshot_list_output(struct mi_writer *writer,
1236                 struct lttng_snapshot_output *output)
1237 {
1238         int ret;
1239
1240         /* Open element snapshot output */
1241         ret = mi_lttng_writer_open_element(writer,
1242                         mi_lttng_element_command_snapshot);
1243         if (ret) {
1244                 goto end;
1245         }
1246
1247         /* ID of the snapshot output */
1248         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1249                         mi_lttng_element_id, output->id);
1250         if (ret) {
1251                 goto end;
1252         }
1253
1254         /* Name of the output */
1255         ret = mi_lttng_writer_write_element_string(writer, config_element_name,
1256                         output->name);
1257         if (ret) {
1258                 goto end;
1259         }
1260
1261         /* Destination of the output (ctrl_url)*/
1262         ret = mi_lttng_writer_write_element_string(writer,
1263                         mi_lttng_element_snapshot_ctrl_url, output->ctrl_url);
1264         if (ret) {
1265                 goto end;
1266         }
1267
1268         /* Destination of the output (data_url) */
1269         ret = mi_lttng_writer_write_element_string(writer,
1270                         mi_lttng_element_snapshot_data_url, output->data_url);
1271         if (ret) {
1272                 goto end;
1273         }
1274
1275         /* total size of all stream combined */
1276         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1277                         mi_lttng_element_snapshot_max_size, output->max_size);
1278         if (ret) {
1279                 goto end;
1280         }
1281
1282         /* Close snapshot output element */
1283         ret = mi_lttng_writer_close_element(writer);
1284
1285 end:
1286         return ret;
1287 }
1288
1289 LTTNG_HIDDEN
1290 int mi_lttng_snapshot_del_output(struct mi_writer *writer, int id,
1291                 const char *name, const char *current_session_name)
1292 {
1293         int ret;
1294
1295         /* Open element del_snapshot */
1296         ret = mi_lttng_writer_open_element(writer,
1297                         mi_lttng_element_command_snapshot);
1298         if (ret) {
1299                 goto end;
1300         }
1301
1302
1303         if (id != UINT32_MAX) {
1304                 /* "Snapshot output "id" successfully deleted
1305                  * for "current_session_name"
1306                  * ID of the snapshot output
1307                  */
1308                 ret = mi_lttng_writer_write_element_unsigned_int(writer,
1309                                 mi_lttng_element_id, id);
1310                 if (ret) {
1311                         goto end;
1312                 }
1313         } else {
1314                 /* "Snapshot output "name" successfully deleted
1315                  * for session "current_session_name"
1316                  * Name of the output
1317                  */
1318                 ret = mi_lttng_writer_write_element_string(writer, config_element_name,
1319                                 name);
1320                 if (ret) {
1321                         goto end;
1322                 }
1323         }
1324
1325         /* Snapshot was deleted for session "current_session_name"*/
1326         ret = mi_lttng_writer_write_element_string(writer,
1327                         mi_lttng_element_snapshot_session_name,
1328                         current_session_name);
1329         if (ret) {
1330                 goto end;
1331         }
1332
1333         /* Close snapshot element */
1334         ret = mi_lttng_writer_close_element(writer);
1335
1336 end:
1337         return ret;
1338 }
1339
1340 LTTNG_HIDDEN
1341 int mi_lttng_snapshot_add_output(struct mi_writer *writer,
1342                 const char *current_session_name, const char *n_ptr,
1343                 struct lttng_snapshot_output *output)
1344 {
1345         int ret;
1346
1347         /* Open element snapshot */
1348         ret = mi_lttng_writer_open_element(writer,
1349                         mi_lttng_element_command_snapshot);
1350         if (ret) {
1351                 goto end;
1352         }
1353
1354         /* Snapshot output id */
1355         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1356                         mi_lttng_element_id, output->id);
1357         if (ret) {
1358                 goto end;
1359         }
1360
1361         /* Snapshot output names */
1362         ret = mi_lttng_writer_write_element_string(writer,
1363                         config_element_name, n_ptr);
1364         if (ret) {
1365                 goto end;
1366         }
1367
1368         /* Destination of the output (ctrl_url)*/
1369         ret = mi_lttng_writer_write_element_string(writer,
1370                         mi_lttng_element_snapshot_ctrl_url, output->ctrl_url);
1371         if (ret) {
1372                 goto end;
1373         }
1374
1375         /* Snapshot added for session "current_session_name"*/
1376         ret = mi_lttng_writer_write_element_string(writer,
1377                         mi_lttng_element_snapshot_session_name, current_session_name);
1378         if (ret) {
1379                 goto end;
1380         }
1381
1382         /* total size of all stream combined */
1383         ret = mi_lttng_writer_write_element_unsigned_int(writer,
1384                         mi_lttng_element_snapshot_max_size, output->max_size);
1385         if (ret) {
1386                 goto end;
1387         }
1388
1389         /* Close snapshot element */
1390         ret = mi_lttng_writer_close_element(writer);
1391
1392 end:
1393         return ret;
1394 }
1395
1396 LTTNG_HIDDEN
1397 int mi_lttng_snapshot_record(struct mi_writer *writer,
1398                 const char *current_session_name, const char *url,
1399                 const char *cmdline_ctrl_url, const char *cmdline_data_url)
1400 {
1401         int ret;
1402
1403         /* Open element snapshot */
1404         ret = mi_lttng_writer_open_element(writer,
1405                         mi_lttng_element_command_snapshot);
1406         if (ret) {
1407                 goto end;
1408         }
1409
1410         /*
1411          * If a valid an URL was given, serialize it,
1412          * else take the command line data and ctrl urls*/
1413         if (url) {
1414                 /* Destination of the output (ctrl_url)*/
1415                 ret = mi_lttng_writer_write_element_string(writer,
1416                                 mi_lttng_element_snapshot_ctrl_url, url);
1417                 if (ret) {
1418                         goto end;
1419                 }
1420         } else if (cmdline_ctrl_url) {
1421                 /* Destination of the output (ctrl_url)*/
1422                 ret = mi_lttng_writer_write_element_string(writer,
1423                                 mi_lttng_element_snapshot_ctrl_url, cmdline_ctrl_url);
1424                 if (ret) {
1425                         goto end;
1426                 }
1427
1428                 /* Destination of the output (data_url) */
1429                 ret = mi_lttng_writer_write_element_string(writer,
1430                                 mi_lttng_element_snapshot_data_url, cmdline_data_url);
1431                 if (ret) {
1432                         goto end;
1433                 }
1434         }
1435
1436         /* Close record_snapshot element */
1437         ret = mi_lttng_writer_close_element(writer);
1438
1439 end:
1440         return ret;
1441 }