src/plugins/text/dmesg/dmesg.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   5  * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
   6  */
   7
   8 #define BT_COMP_LOG_SELF_COMP (dmesg_comp->self_comp)
   9 #define BT_LOG_OUTPUT_LEVEL (dmesg_comp->log_level)
  10 #define BT_LOG_TAG "PLUGIN/SRC.TEXT.DMESG"
  11 #include "logging/comp-logging.h"
  12
  13 #include "dmesg.h"
  14
  15 #include <stdbool.h>
  16 #include <string.h>
  17 #include <ctype.h>
  18 #include <stdio.h>
  19 #include "common/common.h"
  20 #include "common/assert.h"
  21 #include <babeltrace2/babeltrace.h>
  22 #include "compat/utc.h"
  23 #include "compat/stdio.h"
  24 #include <glib.h>
  25 #include "plugins/common/param-validation/param-validation.h"
  26
  27 #define NSEC_PER_USEC 1000UL
  28 #define NSEC_PER_MSEC 1000000UL
  29 #define NSEC_PER_SEC 1000000000ULL
  30 #define USEC_PER_SEC 1000000UL
  31
  32 struct dmesg_component;
  33
  34 struct dmesg_msg_iter {
  35         struct dmesg_component *dmesg_comp;
  36
  37         /* Weak */
  38         bt_self_message_iterator *self_msg_iter;
  39
  40         char *linebuf;
  41         size_t linebuf_len;
  42         FILE *fp;
  43         bt_message *tmp_event_msg;
  44         uint64_t last_clock_value;
  45
  46         enum {
  47                 STATE_EMIT_STREAM_BEGINNING,
  48                 STATE_EMIT_EVENT,
  49                 STATE_EMIT_STREAM_END,
  50                 STATE_DONE,
  51         } state;
  52 };
  53
  54 struct dmesg_component {
  55         bt_logging_level log_level;
  56
  57         struct {
  58                 GString *path;
  59                 bt_bool read_from_stdin;
  60                 bt_bool no_timestamp;
  61         } params;
  62
  63         bt_self_component_source *self_comp_src;
  64         bt_self_component *self_comp;
  65         bt_trace_class *trace_class;
  66         bt_stream_class *stream_class;
  67         bt_event_class *event_class;
  68         bt_trace *trace;
  69         bt_stream *stream;
  70         bt_clock_class *clock_class;
  71 };
  72
  73 static
  74 bt_field_class *create_event_payload_fc(struct dmesg_component *dmesg_comp,
  75                 bt_trace_class *trace_class)
  76 {
  77         bt_field_class *root_fc = NULL;
  78         bt_field_class *fc = NULL;
  79         int ret;
  80
  81         root_fc = bt_field_class_structure_create(trace_class);
  82         if (!root_fc) {
  83                 BT_COMP_LOGE_STR("Cannot create an empty structure field class object.");
  84                 goto error;
  85         }
  86
  87         fc = bt_field_class_string_create(trace_class);
  88         if (!fc) {
  89                 BT_COMP_LOGE_STR("Cannot create a string field class object.");
  90                 goto error;
  91         }
  92
  93         ret = bt_field_class_structure_append_member(root_fc,
  94                 "str", fc);
  95         if (ret) {
  96                 BT_COMP_LOGE("Cannot add `str` member to structure field class: "
  97                         "ret=%d", ret);
  98                 goto error;
  99         }
 100
 101         goto end;
 102
 103 error:
 104         BT_FIELD_CLASS_PUT_REF_AND_RESET(root_fc);
 105
 106 end:
 107         bt_field_class_put_ref(fc);
 108         return root_fc;
 109 }
 110
 111 static
 112 int create_meta(struct dmesg_component *dmesg_comp, bool has_ts)
 113 {
 114         bt_field_class *fc = NULL;
 115         int ret = 0;
 116
 117         dmesg_comp->trace_class = bt_trace_class_create(dmesg_comp->self_comp);
 118         if (!dmesg_comp->trace_class) {
 119                 BT_COMP_LOGE_STR("Cannot create an empty trace class object.");
 120                 goto error;
 121         }
 122
 123         dmesg_comp->stream_class = bt_stream_class_create(
 124                 dmesg_comp->trace_class);
 125         if (!dmesg_comp->stream_class) {
 126                 BT_COMP_LOGE_STR("Cannot create a stream class object.");
 127                 goto error;
 128         }
 129
 130         if (has_ts) {
 131                 dmesg_comp->clock_class = bt_clock_class_create(
 132                         dmesg_comp->self_comp);
 133                 if (!dmesg_comp->clock_class) {
 134                         BT_COMP_LOGE_STR("Cannot create clock class.");
 135                         goto error;
 136                 }
 137
 138                 /*
 139                  * The `dmesg` timestamp's origin is not the Unix epoch,
 140                  * it's the boot time.
 141                  */
 142                 bt_clock_class_set_origin_is_unix_epoch(dmesg_comp->clock_class,
 143                         BT_FALSE);
 144
 145                 ret = bt_stream_class_set_default_clock_class(
 146                         dmesg_comp->stream_class, dmesg_comp->clock_class);
 147                 if (ret) {
 148                         BT_COMP_LOGE_STR("Cannot set stream class's default clock class.");
 149                         goto error;
 150                 }
 151         }
 152
 153         dmesg_comp->event_class = bt_event_class_create(
 154                 dmesg_comp->stream_class);
 155         if (!dmesg_comp->event_class) {
 156                 BT_COMP_LOGE_STR("Cannot create an event class object.");
 157                 goto error;
 158         }
 159
 160         ret = bt_event_class_set_name(dmesg_comp->event_class, "string");
 161         if (ret) {
 162                 BT_COMP_LOGE_STR("Cannot set event class's name.");
 163                 goto error;
 164         }
 165
 166         fc = create_event_payload_fc(dmesg_comp, dmesg_comp->trace_class);
 167         if (!fc) {
 168                 BT_COMP_LOGE_STR("Cannot create event payload field class.");
 169                 goto error;
 170         }
 171
 172         ret = bt_event_class_set_payload_field_class(dmesg_comp->event_class, fc);
 173         if (ret) {
 174                 BT_COMP_LOGE_STR("Cannot set event class's event payload field class.");
 175                 goto error;
 176         }
 177
 178         goto end;
 179
 180 error:
 181         ret = -1;
 182
 183 end:
 184         bt_field_class_put_ref(fc);
 185         return ret;
 186 }
 187
 188 static
 189 struct bt_param_validation_map_value_entry_descr dmesg_params[] = {
 190         { "no-extract-timestamp", BT_PARAM_VALIDATION_MAP_VALUE_ENTRY_OPTIONAL, { .type = BT_VALUE_TYPE_BOOL } },
 191         { "path", BT_PARAM_VALIDATION_MAP_VALUE_ENTRY_OPTIONAL, { .type = BT_VALUE_TYPE_STRING } },
 192         BT_PARAM_VALIDATION_MAP_VALUE_ENTRY_END
 193 };
 194
 195 static
 196 bt_component_class_initialize_method_status handle_params(
 197                 struct dmesg_component *dmesg_comp,
 198                 const bt_value *params)
 199 {
 200         const bt_value *no_timestamp = NULL;
 201         const bt_value *path = NULL;
 202         bt_component_class_initialize_method_status status;
 203         enum bt_param_validation_status validation_status;
 204         gchar *validate_error = NULL;
 205
 206         validation_status = bt_param_validation_validate(params,
 207                 dmesg_params, &validate_error);
 208         if (validation_status == BT_PARAM_VALIDATION_STATUS_MEMORY_ERROR) {
 209                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
 210                 goto end;
 211         } else if (validation_status == BT_PARAM_VALIDATION_STATUS_VALIDATION_ERROR) {
 212                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 213                 BT_COMP_LOGE_APPEND_CAUSE(dmesg_comp->self_comp,
 214                         "%s", validate_error);
 215                 goto end;
 216         }
 217
 218         no_timestamp = bt_value_map_borrow_entry_value_const(params,
 219                 "no-extract-timestamp");
 220         if (no_timestamp) {
 221                 dmesg_comp->params.no_timestamp =
 222                         bt_value_bool_get(no_timestamp);
 223         }
 224
 225         path = bt_value_map_borrow_entry_value_const(params, "path");
 226         if (path) {
 227                 const char *path_str = bt_value_string_get(path);
 228
 229                 g_string_assign(dmesg_comp->params.path, path_str);
 230         } else {
 231                 dmesg_comp->params.read_from_stdin = true;
 232         }
 233
 234         status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_OK;
 235 end:
 236         g_free(validate_error);
 237
 238         return status;
 239 }
 240
 241 static
 242 int create_stream_and_trace(struct dmesg_component *dmesg_comp)
 243 {
 244         int ret = 0;
 245         const char *trace_name = NULL;
 246         gchar *basename = NULL;
 247
 248         dmesg_comp->trace = bt_trace_create(dmesg_comp->trace_class);
 249         if (!dmesg_comp->trace) {
 250                 BT_COMP_LOGE_STR("Cannot create trace object.");
 251                 goto error;
 252         }
 253
 254         if (dmesg_comp->params.read_from_stdin) {
 255                 trace_name = "STDIN";
 256         } else {
 257                 basename = g_path_get_basename(dmesg_comp->params.path->str);
 258                 BT_ASSERT(basename);
 259
 260                 if (strcmp(basename, G_DIR_SEPARATOR_S) != 0 &&
 261                                 strcmp(basename, ".") != 0) {
 262                         trace_name = basename;
 263                 }
 264         }
 265
 266         if (trace_name) {
 267                 ret = bt_trace_set_name(dmesg_comp->trace, trace_name);
 268                 if (ret) {
 269                         BT_COMP_LOGE("Cannot set trace's name: name=\"%s\"",
 270                                 trace_name);
 271                         goto error;
 272                 }
 273         }
 274
 275         dmesg_comp->stream = bt_stream_create(dmesg_comp->stream_class,
 276                 dmesg_comp->trace);
 277         if (!dmesg_comp->stream) {
 278                 BT_COMP_LOGE_STR("Cannot create stream object.");
 279                 goto error;
 280         }
 281
 282         goto end;
 283
 284 error:
 285         ret = -1;
 286
 287 end:
 288         g_free(basename);
 289
 290         return ret;
 291 }
 292
 293 static
 294 int try_create_meta_stream(struct dmesg_component *dmesg_comp, bool has_ts)
 295 {
 296         int ret = 0;
 297
 298         if (dmesg_comp->trace) {
 299                 /* Already created */
 300                 goto end;
 301         }
 302
 303         ret = create_meta(dmesg_comp, has_ts);
 304         if (ret) {
 305                 BT_COMP_LOGE("Cannot create metadata objects: dmesg-comp-addr=%p",
 306                         dmesg_comp);
 307                 goto error;
 308         }
 309
 310         ret = create_stream_and_trace(dmesg_comp);
 311         if (ret) {
 312                 BT_COMP_LOGE("Cannot create stream object: "
 313                         "dmesg-comp-addr=%p", dmesg_comp);
 314                 goto error;
 315         }
 316
 317         goto end;
 318
 319 error:
 320         ret = -1;
 321
 322 end:
 323         return ret;
 324 }
 325
 326 static
 327 void destroy_dmesg_component(struct dmesg_component *dmesg_comp)
 328 {
 329         if (!dmesg_comp) {
 330                 return;
 331         }
 332
 333         if (dmesg_comp->params.path) {
 334                 g_string_free(dmesg_comp->params.path, TRUE);
 335         }
 336
 337         bt_trace_put_ref(dmesg_comp->trace);
 338         bt_stream_class_put_ref(dmesg_comp->stream_class);
 339         bt_event_class_put_ref(dmesg_comp->event_class);
 340         bt_stream_put_ref(dmesg_comp->stream);
 341         bt_clock_class_put_ref(dmesg_comp->clock_class);
 342         bt_trace_class_put_ref(dmesg_comp->trace_class);
 343         g_free(dmesg_comp);
 344 }
 345
 346 BT_HIDDEN
 347 bt_component_class_initialize_method_status dmesg_init(
 348                 bt_self_component_source *self_comp_src,
 349                 bt_self_component_source_configuration *config,
 350                 const bt_value *params, void *init_method_data)
 351 {
 352         struct dmesg_component *dmesg_comp = g_new0(struct dmesg_component, 1);
 353         bt_component_class_initialize_method_status status;
 354         bt_self_component *self_comp =
 355                 bt_self_component_source_as_self_component(self_comp_src);
 356         const bt_component *comp = bt_self_component_as_component(self_comp);
 357         bt_logging_level log_level = bt_component_get_logging_level(comp);
 358         bt_self_component_add_port_status add_port_status;
 359
 360         if (!dmesg_comp) {
 361                 /* Implicit log level is not available here */
 362                 BT_COMP_LOG_CUR_LVL(BT_LOG_ERROR, log_level, self_comp,
 363                         "Failed to allocate one dmesg component structure.");
 364                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 365                 goto error;
 366         }
 367
 368         dmesg_comp->log_level = log_level;
 369         dmesg_comp->self_comp = self_comp;
 370         dmesg_comp->self_comp_src = self_comp_src;
 371         dmesg_comp->params.path = g_string_new(NULL);
 372         if (!dmesg_comp->params.path) {
 373                 BT_COMP_LOGE_STR("Failed to allocate a GString.");
 374                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 375                 goto error;
 376         }
 377
 378         status = handle_params(dmesg_comp, params);
 379         if (status != BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_OK) {
 380                 BT_COMP_LOGE("Invalid parameters: comp-addr=%p", self_comp);
 381                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 382                 goto error;
 383         }
 384
 385         if (!dmesg_comp->params.read_from_stdin &&
 386                         !g_file_test(dmesg_comp->params.path->str,
 387                         G_FILE_TEST_IS_REGULAR)) {
 388                 BT_COMP_LOGE("Input path is not a regular file: "
 389                         "comp-addr=%p, path=\"%s\"", self_comp,
 390                         dmesg_comp->params.path->str);
 391                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 392                 goto error;
 393         }
 394
 395         add_port_status = bt_self_component_source_add_output_port(
 396                 self_comp_src, "out", NULL, NULL);
 397         if (add_port_status != BT_SELF_COMPONENT_ADD_PORT_STATUS_OK) {
 398                 status = (int) add_port_status;
 399                 goto error;
 400         }
 401
 402         bt_self_component_set_data(self_comp, dmesg_comp);
 403         BT_COMP_LOGI_STR("Component initialized.");
 404
 405         status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_OK;
 406         goto end;
 407
 408 error:
 409         destroy_dmesg_component(dmesg_comp);
 410         bt_self_component_set_data(self_comp, NULL);
 411
 412 end:
 413         return status;
 414 }
 415
 416 BT_HIDDEN
 417 void dmesg_finalize(bt_self_component_source *self_comp)
 418 {
 419         destroy_dmesg_component(bt_self_component_get_data(
 420                 bt_self_component_source_as_self_component(self_comp)));
 421 }
 422
 423 static
 424 bt_message *create_init_event_msg_from_line(
 425                 struct dmesg_msg_iter *msg_iter,
 426                 const char *line, const char **new_start)
 427 {
 428         bt_event *event;
 429         bt_message *msg = NULL;
 430         bool has_timestamp = false;
 431         unsigned long sec, usec, msec;
 432         unsigned int year, mon, mday, hour, min;
 433         uint64_t ts = 0;
 434         int ret = 0;
 435         struct dmesg_component *dmesg_comp = msg_iter->dmesg_comp;
 436
 437         *new_start = line;
 438
 439         if (dmesg_comp->params.no_timestamp) {
 440                 goto skip_ts;
 441         }
 442
 443         /* Extract time from input line */
 444         if (sscanf(line, "[%lu.%lu] ", &sec, &usec) == 2) {
 445                 ts = (uint64_t) sec * USEC_PER_SEC + (uint64_t) usec;
 446
 447                 /*
 448                  * The clock class we use has a 1 GHz frequency: convert
 449                  * from µs to ns.
 450                  */
 451                 ts *= NSEC_PER_USEC;
 452                 has_timestamp = true;
 453         } else if (sscanf(line, "[%u-%u-%u %u:%u:%lu.%lu] ",
 454                         &year, &mon, &mday, &hour, &min,
 455                         &sec, &msec) == 7) {
 456                 time_t ep_sec;
 457                 struct tm ti;
 458
 459                 memset(&ti, 0, sizeof(ti));
 460                 ti.tm_year = year - 1900;       /* From 1900 */
 461                 ti.tm_mon = mon - 1;            /* 0 to 11 */
 462                 ti.tm_mday = mday;
 463                 ti.tm_hour = hour;
 464                 ti.tm_min = min;
 465                 ti.tm_sec = sec;
 466
 467                 ep_sec = bt_timegm(&ti);
 468                 if (ep_sec != (time_t) -1) {
 469                         ts = (uint64_t) ep_sec * NSEC_PER_SEC
 470                                 + (uint64_t) msec * NSEC_PER_MSEC;
 471                 }
 472
 473                 has_timestamp = true;
 474         }
 475
 476         if (has_timestamp) {
 477                 /* Set new start for the message portion of the line */
 478                 *new_start = strchr(line, ']');
 479                 BT_ASSERT_DBG(*new_start);
 480                 (*new_start)++;
 481
 482                 if ((*new_start)[0] == ' ') {
 483                         (*new_start)++;
 484                 }
 485         }
 486
 487 skip_ts:
 488         /*
 489          * At this point, we know if the stream class's event header
 490          * field class should have a timestamp or not, so we can lazily
 491          * create the metadata and stream objects.
 492          */
 493         ret = try_create_meta_stream(dmesg_comp, has_timestamp);
 494         if (ret) {
 495                 /* try_create_meta_stream() logs errors */
 496                 goto error;
 497         }
 498
 499         if (dmesg_comp->clock_class) {
 500                 msg = bt_message_event_create_with_default_clock_snapshot(
 501                         msg_iter->self_msg_iter,
 502                         dmesg_comp->event_class, dmesg_comp->stream, ts);
 503                 msg_iter->last_clock_value = ts;
 504         } else {
 505                 msg = bt_message_event_create(msg_iter->self_msg_iter,
 506                         dmesg_comp->event_class, dmesg_comp->stream);
 507         }
 508
 509         if (!msg) {
 510                 BT_COMP_LOGE_STR("Cannot create event message.");
 511                 goto error;
 512         }
 513
 514         event = bt_message_event_borrow_event(msg);
 515         BT_ASSERT_DBG(event);
 516         goto end;
 517
 518 error:
 519         BT_MESSAGE_PUT_REF_AND_RESET(msg);
 520
 521 end:
 522         return msg;
 523 }
 524
 525 static
 526 int fill_event_payload_from_line(struct dmesg_component *dmesg_comp,
 527                 const char *line, bt_event *event)
 528 {
 529         bt_field *ep_field = NULL;
 530         bt_field *str_field = NULL;
 531         size_t len;
 532         int ret;
 533
 534         ep_field = bt_event_borrow_payload_field(event);
 535         BT_ASSERT_DBG(ep_field);
 536         str_field = bt_field_structure_borrow_member_field_by_index(
 537                 ep_field, 0);
 538         if (!str_field) {
 539                 BT_COMP_LOGE_STR("Cannot borrow `timestamp` field from event payload structure field.");
 540                 goto error;
 541         }
 542
 543         len = strlen(line);
 544         if (line[len - 1] == '\n') {
 545                 /* Do not include the newline character in the payload */
 546                 len--;
 547         }
 548
 549         bt_field_string_clear(str_field);
 550         ret = bt_field_string_append_with_length(str_field, line, len);
 551         if (ret) {
 552                 BT_COMP_LOGE("Cannot append value to string field object: "
 553                         "len=%zu", len);
 554                 goto error;
 555         }
 556
 557         goto end;
 558
 559 error:
 560         ret = -1;
 561
 562 end:
 563         return ret;
 564 }
 565
 566 static
 567 bt_message *create_msg_from_line(
 568                 struct dmesg_msg_iter *dmesg_msg_iter, const char *line)
 569 {
 570         struct dmesg_component *dmesg_comp = dmesg_msg_iter->dmesg_comp;
 571         bt_event *event = NULL;
 572         bt_message *msg = NULL;
 573         const char *new_start;
 574         int ret;
 575
 576         msg = create_init_event_msg_from_line(dmesg_msg_iter,
 577                 line, &new_start);
 578         if (!msg) {
 579                 BT_COMP_LOGE_STR("Cannot create and initialize event message from line.");
 580                 goto error;
 581         }
 582
 583         event = bt_message_event_borrow_event(msg);
 584         BT_ASSERT_DBG(event);
 585         ret = fill_event_payload_from_line(dmesg_comp, new_start, event);
 586         if (ret) {
 587                 BT_COMP_LOGE("Cannot fill event payload field from line: "
 588                         "ret=%d", ret);
 589                 goto error;
 590         }
 591
 592         goto end;
 593
 594 error:
 595         BT_MESSAGE_PUT_REF_AND_RESET(msg);
 596
 597 end:
 598         return msg;
 599 }
 600
 601 static
 602 void destroy_dmesg_msg_iter(struct dmesg_msg_iter *dmesg_msg_iter)
 603 {
 604         struct dmesg_component *dmesg_comp;
 605
 606         if (!dmesg_msg_iter) {
 607                 return;
 608         }
 609
 610         dmesg_comp = dmesg_msg_iter->dmesg_comp;
 611
 612         if (dmesg_msg_iter->fp && dmesg_msg_iter->fp != stdin) {
 613                 if (fclose(dmesg_msg_iter->fp)) {
 614                         BT_COMP_LOGE_ERRNO("Cannot close input file", ".");
 615                 }
 616         }
 617
 618         bt_message_put_ref(dmesg_msg_iter->tmp_event_msg);
 619         free(dmesg_msg_iter->linebuf);
 620         g_free(dmesg_msg_iter);
 621 }
 622
 623
 624
 625 BT_HIDDEN
 626 bt_message_iterator_class_initialize_method_status dmesg_msg_iter_init(
 627                 bt_self_message_iterator *self_msg_iter,
 628                 bt_self_message_iterator_configuration *config,
 629                 bt_self_component_port_output *self_port)
 630 {
 631         bt_self_component *self_comp =
 632                 bt_self_message_iterator_borrow_component(self_msg_iter);
 633         struct dmesg_component *dmesg_comp = bt_self_component_get_data(self_comp);
 634         struct dmesg_msg_iter *dmesg_msg_iter =
 635                 g_new0(struct dmesg_msg_iter, 1);
 636         bt_message_iterator_class_initialize_method_status status =
 637                 BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_OK;
 638
 639         if (!dmesg_msg_iter) {
 640                 BT_COMP_LOGE_STR("Failed to allocate on dmesg message iterator structure.");
 641                 goto error;
 642         }
 643
 644         BT_ASSERT(dmesg_comp);
 645         dmesg_msg_iter->dmesg_comp = dmesg_comp;
 646         dmesg_msg_iter->self_msg_iter = self_msg_iter;
 647
 648         if (dmesg_comp->params.read_from_stdin) {
 649                 dmesg_msg_iter->fp = stdin;
 650         } else {
 651                 dmesg_msg_iter->fp = fopen(dmesg_comp->params.path->str, "r");
 652                 if (!dmesg_msg_iter->fp) {
 653                         BT_COMP_LOGE_ERRNO("Cannot open input file in read mode", ": path=\"%s\"",
 654                                 dmesg_comp->params.path->str);
 655                         goto error;
 656                 }
 657         }
 658
 659         bt_self_message_iterator_set_data(self_msg_iter,
 660                 dmesg_msg_iter);
 661         goto end;
 662
 663 error:
 664         destroy_dmesg_msg_iter(dmesg_msg_iter);
 665         bt_self_message_iterator_set_data(self_msg_iter, NULL);
 666         if (status >= 0) {
 667                 status = BT_MESSAGE_ITERATOR_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 668         }
 669
 670 end:
 671         return status;
 672 }
 673
 674 BT_HIDDEN
 675 void dmesg_msg_iter_finalize(
 676                 bt_self_message_iterator *priv_msg_iter)
 677 {
 678         destroy_dmesg_msg_iter(bt_self_message_iterator_get_data(
 679                 priv_msg_iter));
 680 }
 681
 682 static
 683 bt_message_iterator_class_next_method_status dmesg_msg_iter_next_one(
 684                 struct dmesg_msg_iter *dmesg_msg_iter,
 685                 bt_message **msg)
 686 {
 687         ssize_t len;
 688         struct dmesg_component *dmesg_comp;
 689         bt_message_iterator_class_next_method_status status;
 690
 691         BT_ASSERT_DBG(dmesg_msg_iter);
 692         dmesg_comp = dmesg_msg_iter->dmesg_comp;
 693         BT_ASSERT_DBG(dmesg_comp);
 694
 695         if (dmesg_msg_iter->state == STATE_DONE) {
 696                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_END;
 697                 goto end;
 698         }
 699
 700         if (dmesg_msg_iter->tmp_event_msg ||
 701                         dmesg_msg_iter->state == STATE_EMIT_STREAM_END) {
 702                 goto handle_state;
 703         }
 704
 705         while (true) {
 706                 const char *ch;
 707                 bool only_spaces = true;
 708
 709                 len = bt_getline(&dmesg_msg_iter->linebuf,
 710                         &dmesg_msg_iter->linebuf_len, dmesg_msg_iter->fp);
 711                 if (len < 0) {
 712                         if (errno == EINVAL) {
 713                                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 714                                 goto end;
 715                         } else if (errno == ENOMEM) {
 716                                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_MEMORY_ERROR;
 717                                 goto end;
 718                         } else {
 719                                 if (dmesg_msg_iter->state == STATE_EMIT_STREAM_BEGINNING) {
 720                                         /* Stream did not even begin */
 721                                         status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_END;
 722                                         goto end;
 723                                 } else {
 724                                         /* End stream now */
 725                                         dmesg_msg_iter->state =
 726                                                 STATE_EMIT_STREAM_END;
 727                                         goto handle_state;
 728                                 }
 729                         }
 730                 }
 731
 732                 BT_ASSERT_DBG(dmesg_msg_iter->linebuf);
 733
 734                 /* Ignore empty lines, once trimmed */
 735                 for (ch = dmesg_msg_iter->linebuf; *ch != '\0'; ch++) {
 736                         if (!isspace((unsigned char) *ch)) {
 737                                 only_spaces = false;
 738                                 break;
 739                         }
 740                 }
 741
 742                 if (!only_spaces) {
 743                         break;
 744                 }
 745         }
 746
 747         dmesg_msg_iter->tmp_event_msg = create_msg_from_line(
 748                 dmesg_msg_iter, dmesg_msg_iter->linebuf);
 749         if (!dmesg_msg_iter->tmp_event_msg) {
 750                 BT_COMP_LOGE("Cannot create event message from line: "
 751                         "dmesg-comp-addr=%p, line=\"%s\"", dmesg_comp,
 752                         dmesg_msg_iter->linebuf);
 753                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 754                 goto end;
 755         }
 756
 757 handle_state:
 758         BT_ASSERT_DBG(dmesg_comp->trace);
 759
 760         switch (dmesg_msg_iter->state) {
 761         case STATE_EMIT_STREAM_BEGINNING:
 762                 BT_ASSERT_DBG(dmesg_msg_iter->tmp_event_msg);
 763                 *msg = bt_message_stream_beginning_create(
 764                         dmesg_msg_iter->self_msg_iter, dmesg_comp->stream);
 765                 dmesg_msg_iter->state = STATE_EMIT_EVENT;
 766                 break;
 767         case STATE_EMIT_EVENT:
 768                 BT_ASSERT_DBG(dmesg_msg_iter->tmp_event_msg);
 769                 *msg = dmesg_msg_iter->tmp_event_msg;
 770                 dmesg_msg_iter->tmp_event_msg = NULL;
 771                 break;
 772         case STATE_EMIT_STREAM_END:
 773                 *msg = bt_message_stream_end_create(
 774                         dmesg_msg_iter->self_msg_iter, dmesg_comp->stream);
 775                 dmesg_msg_iter->state = STATE_DONE;
 776                 break;
 777         default:
 778                 break;
 779         }
 780
 781         if (!*msg) {
 782                 BT_COMP_LOGE("Cannot create message: dmesg-comp-addr=%p",
 783                         dmesg_comp);
 784                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_ERROR;
 785                 goto end;
 786         }
 787
 788         status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 789 end:
 790         return status;
 791 }
 792
 793 BT_HIDDEN
 794 bt_message_iterator_class_next_method_status dmesg_msg_iter_next(
 795                 bt_self_message_iterator *self_msg_iter,
 796                 bt_message_array_const msgs, uint64_t capacity,
 797                 uint64_t *count)
 798 {
 799         struct dmesg_msg_iter *dmesg_msg_iter =
 800                 bt_self_message_iterator_get_data(
 801                         self_msg_iter);
 802         bt_message_iterator_class_next_method_status status =
 803                 BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 804         uint64_t i = 0;
 805
 806         while (i < capacity &&
 807                         status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
 808                 bt_message *priv_msg = NULL;
 809
 810                 status = dmesg_msg_iter_next_one(dmesg_msg_iter,
 811                         &priv_msg);
 812                 msgs[i] = priv_msg;
 813                 if (status == BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK) {
 814                         i++;
 815                 }
 816         }
 817
 818         if (i > 0) {
 819                 /*
 820                  * Even if dmesg_msg_iter_next_one() returned
 821                  * something else than
 822                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK, we
 823                  * accumulated message objects in the output
 824                  * message array, so we need to return
 825                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK so that they
 826                  * are transfered to downstream. This other status
 827                  * occurs again the next time muxer_msg_iter_do_next()
 828                  * is called, possibly without any accumulated
 829                  * message, in which case we'll return it.
 830                  */
 831                 *count = i;
 832                 status = BT_MESSAGE_ITERATOR_CLASS_NEXT_METHOD_STATUS_OK;
 833         }
 834
 835         return status;
 836 }
 837
 838 BT_HIDDEN
 839 bt_message_iterator_class_can_seek_beginning_method_status
 840 dmesg_msg_iter_can_seek_beginning(
 841                 bt_self_message_iterator *self_msg_iter, bt_bool *can_seek)
 842 {
 843         struct dmesg_msg_iter *dmesg_msg_iter =
 844                 bt_self_message_iterator_get_data(self_msg_iter);
 845
 846         /* Can't seek the beginning of the standard input stream */
 847         *can_seek = !dmesg_msg_iter->dmesg_comp->params.read_from_stdin;
 848
 849         return BT_MESSAGE_ITERATOR_CLASS_CAN_SEEK_BEGINNING_METHOD_STATUS_OK;
 850 }
 851
 852 BT_HIDDEN
 853 bt_message_iterator_class_seek_beginning_method_status
 854 dmesg_msg_iter_seek_beginning(
 855                 bt_self_message_iterator *self_msg_iter)
 856 {
 857         struct dmesg_msg_iter *dmesg_msg_iter =
 858                 bt_self_message_iterator_get_data(self_msg_iter);
 859
 860         BT_ASSERT(!dmesg_msg_iter->dmesg_comp->params.read_from_stdin);
 861
 862         BT_MESSAGE_PUT_REF_AND_RESET(dmesg_msg_iter->tmp_event_msg);
 863         dmesg_msg_iter->last_clock_value = 0;
 864         dmesg_msg_iter->state = STATE_EMIT_STREAM_BEGINNING;
 865         return BT_MESSAGE_ITERATOR_CLASS_SEEK_BEGINNING_METHOD_STATUS_OK;
 866 }