plugins/text/dmesg/dmesg.c

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