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