src/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_COMP_LOG_SELF_COMP (dmesg_comp->self_comp)
  25 #define BT_LOG_OUTPUT_LEVEL (dmesg_comp->log_level)
  26 #define BT_LOG_TAG "PLUGIN/SRC.TEXT.DMESG"
  27 #include "plugins/comp-logging.h"
  28
  29 #include <stdbool.h>
  30 #include <string.h>
  31 #include <ctype.h>
  32 #include <stdio.h>
  33 #include "common/common.h"
  34 #include "common/assert.h"
  35 #include <babeltrace2/babeltrace.h>
  36 #include "compat/utc.h"
  37 #include "compat/stdio.h"
  38 #include <glib.h>
  39
  40 #define NSEC_PER_USEC 1000UL
  41 #define NSEC_PER_MSEC 1000000UL
  42 #define NSEC_PER_SEC 1000000000ULL
  43 #define USEC_PER_SEC 1000000UL
  44
  45 struct dmesg_component;
  46
  47 struct dmesg_msg_iter {
  48         struct dmesg_component *dmesg_comp;
  49         bt_self_message_iterator *pc_msg_iter; /* Weak */
  50         char *linebuf;
  51         size_t linebuf_len;
  52         FILE *fp;
  53         bt_message *tmp_event_msg;
  54         uint64_t last_clock_value;
  55
  56         enum {
  57                 STATE_EMIT_STREAM_BEGINNING,
  58                 STATE_EMIT_STREAM_ACTIVITY_BEGINNING,
  59                 STATE_EMIT_PACKET_BEGINNING,
  60                 STATE_EMIT_EVENT,
  61                 STATE_EMIT_PACKET_END,
  62                 STATE_EMIT_STREAM_ACTIVITY_END,
  63                 STATE_EMIT_STREAM_END,
  64                 STATE_DONE,
  65         } state;
  66 };
  67
  68 struct dmesg_component {
  69         bt_logging_level log_level;
  70
  71         struct {
  72                 GString *path;
  73                 bt_bool read_from_stdin;
  74                 bt_bool no_timestamp;
  75         } params;
  76
  77         bt_self_component_source *self_comp_src;
  78         bt_self_component *self_comp;
  79         bt_trace_class *trace_class;
  80         bt_stream_class *stream_class;
  81         bt_event_class *event_class;
  82         bt_trace *trace;
  83         bt_stream *stream;
  84         bt_packet *packet;
  85         bt_clock_class *clock_class;
  86 };
  87
  88 static
  89 bt_field_class *create_event_payload_fc(struct dmesg_component *dmesg_comp,
  90                 bt_trace_class *trace_class)
  91 {
  92         bt_field_class *root_fc = NULL;
  93         bt_field_class *fc = NULL;
  94         int ret;
  95
  96         root_fc = bt_field_class_structure_create(trace_class);
  97         if (!root_fc) {
  98                 BT_COMP_LOGE_STR("Cannot create an empty structure field class object.");
  99                 goto error;
 100         }
 101
 102         fc = bt_field_class_string_create(trace_class);
 103         if (!fc) {
 104                 BT_COMP_LOGE_STR("Cannot create a string field class object.");
 105                 goto error;
 106         }
 107
 108         ret = bt_field_class_structure_append_member(root_fc,
 109                 "str", fc);
 110         if (ret) {
 111                 BT_COMP_LOGE("Cannot add `str` member to structure field class: "
 112                         "ret=%d", ret);
 113                 goto error;
 114         }
 115
 116         goto end;
 117
 118 error:
 119         BT_FIELD_CLASS_PUT_REF_AND_RESET(root_fc);
 120
 121 end:
 122         bt_field_class_put_ref(fc);
 123         return root_fc;
 124 }
 125
 126 static
 127 int create_meta(struct dmesg_component *dmesg_comp, bool has_ts)
 128 {
 129         bt_field_class *fc = NULL;
 130         int ret = 0;
 131
 132         dmesg_comp->trace_class = bt_trace_class_create(dmesg_comp->self_comp);
 133         if (!dmesg_comp->trace_class) {
 134                 BT_COMP_LOGE_STR("Cannot create an empty trace class object.");
 135                 goto error;
 136         }
 137
 138         dmesg_comp->stream_class = bt_stream_class_create(
 139                 dmesg_comp->trace_class);
 140         if (!dmesg_comp->stream_class) {
 141                 BT_COMP_LOGE_STR("Cannot create a stream class object.");
 142                 goto error;
 143         }
 144
 145         if (has_ts) {
 146                 dmesg_comp->clock_class = bt_clock_class_create(
 147                         dmesg_comp->self_comp);
 148                 if (!dmesg_comp->clock_class) {
 149                         BT_COMP_LOGE_STR("Cannot create clock class.");
 150                         goto error;
 151                 }
 152
 153                 /*
 154                  * The `dmesg` timestamp's origin is not the Unix epoch,
 155                  * it's the boot time.
 156                  */
 157                 bt_clock_class_set_origin_is_unix_epoch(dmesg_comp->clock_class,
 158                         BT_FALSE);
 159
 160                 ret = bt_stream_class_set_default_clock_class(
 161                         dmesg_comp->stream_class, dmesg_comp->clock_class);
 162                 if (ret) {
 163                         BT_COMP_LOGE_STR("Cannot set stream class's default clock class.");
 164                         goto error;
 165                 }
 166
 167                 bt_stream_class_set_packets_have_beginning_default_clock_snapshot(
 168                         dmesg_comp->stream_class, BT_TRUE);
 169                 bt_stream_class_set_packets_have_end_default_clock_snapshot(
 170                         dmesg_comp->stream_class, BT_TRUE);
 171         }
 172
 173         dmesg_comp->event_class = bt_event_class_create(
 174                 dmesg_comp->stream_class);
 175         if (!dmesg_comp->event_class) {
 176                 BT_COMP_LOGE_STR("Cannot create an event class object.");
 177                 goto error;
 178         }
 179
 180         ret = bt_event_class_set_name(dmesg_comp->event_class, "string");
 181         if (ret) {
 182                 BT_COMP_LOGE_STR("Cannot set event class's name.");
 183                 goto error;
 184         }
 185
 186         fc = create_event_payload_fc(dmesg_comp, dmesg_comp->trace_class);
 187         if (!fc) {
 188                 BT_COMP_LOGE_STR("Cannot create event payload field class.");
 189                 goto error;
 190         }
 191
 192         ret = bt_event_class_set_payload_field_class(dmesg_comp->event_class, fc);
 193         if (ret) {
 194                 BT_COMP_LOGE_STR("Cannot set event class's event payload field class.");
 195                 goto error;
 196         }
 197
 198         goto end;
 199
 200 error:
 201         ret = -1;
 202
 203 end:
 204         bt_field_class_put_ref(fc);
 205         return ret;
 206 }
 207
 208 static
 209 int handle_params(struct dmesg_component *dmesg_comp,
 210                 const bt_value *params)
 211 {
 212         const bt_value *no_timestamp = NULL;
 213         const bt_value *path = NULL;
 214         const char *path_str;
 215         int ret = 0;
 216
 217         no_timestamp = bt_value_map_borrow_entry_value_const(params,
 218                 "no-extract-timestamp");
 219         if (no_timestamp) {
 220                 if (!bt_value_is_bool(no_timestamp)) {
 221                         BT_COMP_LOGE("Expecting a boolean value for the `no-extract-timestamp` parameter: "
 222                                 "type=%s",
 223                                 bt_common_value_type_string(
 224                                         bt_value_get_type(no_timestamp)));
 225                         goto error;
 226                 }
 227
 228                 dmesg_comp->params.no_timestamp =
 229                         bt_value_bool_get(no_timestamp);
 230         }
 231
 232         path = bt_value_map_borrow_entry_value_const(params, "path");
 233         if (path) {
 234                 if (dmesg_comp->params.read_from_stdin) {
 235                         BT_COMP_LOGE_STR("Cannot specify both `read-from-stdin` and `path` parameters.");
 236                         goto error;
 237                 }
 238
 239                 if (!bt_value_is_string(path)) {
 240                         BT_COMP_LOGE("Expecting a string value for the `path` parameter: "
 241                                 "type=%s",
 242                                 bt_common_value_type_string(
 243                                         bt_value_get_type(path)));
 244                         goto error;
 245                 }
 246
 247                 path_str = bt_value_string_get(path);
 248                 g_string_assign(dmesg_comp->params.path, path_str);
 249         } else {
 250                 dmesg_comp->params.read_from_stdin = true;
 251         }
 252
 253         goto end;
 254
 255 error:
 256         ret = -1;
 257
 258 end:
 259         return ret;
 260 }
 261
 262 static
 263 int create_packet_and_stream_and_trace(struct dmesg_component *dmesg_comp)
 264 {
 265         int ret = 0;
 266         const char *trace_name = NULL;
 267         gchar *basename = NULL;
 268
 269         dmesg_comp->trace = bt_trace_create(dmesg_comp->trace_class);
 270         if (!dmesg_comp->trace) {
 271                 BT_COMP_LOGE_STR("Cannot create trace object.");
 272                 goto error;
 273         }
 274
 275         if (dmesg_comp->params.read_from_stdin) {
 276                 trace_name = "STDIN";
 277         } else {
 278                 basename = g_path_get_basename(dmesg_comp->params.path->str);
 279                 BT_ASSERT(basename);
 280
 281                 if (strcmp(basename, G_DIR_SEPARATOR_S) != 0 &&
 282                                 strcmp(basename, ".") != 0) {
 283                         trace_name = basename;
 284                 }
 285         }
 286
 287         if (trace_name) {
 288                 ret = bt_trace_set_name(dmesg_comp->trace, trace_name);
 289                 if (ret) {
 290                         BT_COMP_LOGE("Cannot set trace's name: name=\"%s\"",
 291                                 trace_name);
 292                         goto error;
 293                 }
 294         }
 295
 296         dmesg_comp->stream = bt_stream_create(dmesg_comp->stream_class,
 297                 dmesg_comp->trace);
 298         if (!dmesg_comp->stream) {
 299                 BT_COMP_LOGE_STR("Cannot create stream object.");
 300                 goto error;
 301         }
 302
 303         dmesg_comp->packet = bt_packet_create(dmesg_comp->stream);
 304         if (!dmesg_comp->packet) {
 305                 BT_COMP_LOGE_STR("Cannot create packet object.");
 306                 goto error;
 307         }
 308
 309         goto end;
 310
 311 error:
 312         ret = -1;
 313
 314 end:
 315         if (basename) {
 316                 g_free(basename);
 317         }
 318
 319         return ret;
 320 }
 321
 322 static
 323 int try_create_meta_stream_packet(struct dmesg_component *dmesg_comp,
 324                 bool has_ts)
 325 {
 326         int ret = 0;
 327
 328         if (dmesg_comp->trace) {
 329                 /* Already created */
 330                 goto end;
 331         }
 332
 333         ret = create_meta(dmesg_comp, has_ts);
 334         if (ret) {
 335                 BT_COMP_LOGE("Cannot create metadata objects: dmesg-comp-addr=%p",
 336                         dmesg_comp);
 337                 goto error;
 338         }
 339
 340         ret = create_packet_and_stream_and_trace(dmesg_comp);
 341         if (ret) {
 342                 BT_COMP_LOGE("Cannot create packet and stream objects: "
 343                         "dmesg-comp-addr=%p", dmesg_comp);
 344                 goto error;
 345         }
 346
 347         goto end;
 348
 349 error:
 350         ret = -1;
 351
 352 end:
 353         return ret;
 354 }
 355
 356 static
 357 void destroy_dmesg_component(struct dmesg_component *dmesg_comp)
 358 {
 359         if (!dmesg_comp) {
 360                 return;
 361         }
 362
 363         if (dmesg_comp->params.path) {
 364                 g_string_free(dmesg_comp->params.path, TRUE);
 365         }
 366
 367         bt_packet_put_ref(dmesg_comp->packet);
 368         bt_trace_put_ref(dmesg_comp->trace);
 369         bt_stream_class_put_ref(dmesg_comp->stream_class);
 370         bt_event_class_put_ref(dmesg_comp->event_class);
 371         bt_stream_put_ref(dmesg_comp->stream);
 372         bt_clock_class_put_ref(dmesg_comp->clock_class);
 373         bt_trace_class_put_ref(dmesg_comp->trace_class);
 374         g_free(dmesg_comp);
 375 }
 376
 377 static
 378 bt_self_component_status create_port(
 379                 bt_self_component_source *self_comp)
 380 {
 381         return bt_self_component_source_add_output_port(self_comp,
 382                 "out", NULL, NULL);
 383 }
 384
 385 BT_HIDDEN
 386 bt_self_component_status dmesg_init(
 387                 bt_self_component_source *self_comp_src,
 388                 bt_value *params, void *init_method_data)
 389 {
 390         int ret = 0;
 391         struct dmesg_component *dmesg_comp = g_new0(struct dmesg_component, 1);
 392         bt_self_component_status status = BT_SELF_COMPONENT_STATUS_OK;
 393         bt_self_component *self_comp =
 394                 bt_self_component_source_as_self_component(self_comp_src);
 395         const bt_component *comp = bt_self_component_as_component(self_comp);
 396         bt_logging_level log_level = bt_component_get_logging_level(comp);
 397
 398         if (!dmesg_comp) {
 399                 /* Implicit log level is not available here */
 400                 BT_COMP_LOG_CUR_LVL(BT_LOG_ERROR, log_level, self_comp,
 401                         "Failed to allocate one dmesg component structure.");
 402                 goto error;
 403         }
 404
 405         dmesg_comp->log_level = log_level;
 406         dmesg_comp->self_comp = self_comp;
 407         dmesg_comp->self_comp_src = self_comp_src;
 408         dmesg_comp->params.path = g_string_new(NULL);
 409         if (!dmesg_comp->params.path) {
 410                 BT_COMP_LOGE_STR("Failed to allocate a GString.");
 411                 goto error;
 412         }
 413
 414         ret = handle_params(dmesg_comp, params);
 415         if (ret) {
 416                 BT_COMP_LOGE("Invalid parameters: comp-addr=%p", self_comp);
 417                 goto error;
 418         }
 419
 420         if (!dmesg_comp->params.read_from_stdin &&
 421                         !g_file_test(dmesg_comp->params.path->str,
 422                         G_FILE_TEST_IS_REGULAR)) {
 423                 BT_COMP_LOGE("Input path is not a regular file: "
 424                         "comp-addr=%p, path=\"%s\"", self_comp,
 425                         dmesg_comp->params.path->str);
 426                 goto error;
 427         }
 428
 429         status = create_port(self_comp_src);
 430         if (status != BT_SELF_COMPONENT_STATUS_OK) {
 431                 goto error;
 432         }
 433
 434         bt_self_component_set_data(self_comp, dmesg_comp);
 435         BT_COMP_LOGI_STR("Component initialized.");
 436         goto end;
 437
 438 error:
 439         destroy_dmesg_component(dmesg_comp);
 440         bt_self_component_set_data(self_comp, NULL);
 441
 442         if (status >= 0) {
 443                 status = BT_SELF_COMPONENT_STATUS_ERROR;
 444         }
 445
 446 end:
 447         return status;
 448 }
 449
 450 BT_HIDDEN
 451 void dmesg_finalize(bt_self_component_source *self_comp)
 452 {
 453         destroy_dmesg_component(bt_self_component_get_data(
 454                 bt_self_component_source_as_self_component(self_comp)));
 455 }
 456
 457 static
 458 bt_message *create_init_event_msg_from_line(
 459                 struct dmesg_msg_iter *msg_iter,
 460                 const char *line, const char **new_start)
 461 {
 462         bt_event *event;
 463         bt_message *msg = NULL;
 464         bool has_timestamp = false;
 465         unsigned long sec, usec, msec;
 466         unsigned int year, mon, mday, hour, min;
 467         uint64_t ts = 0;
 468         int ret = 0;
 469         struct dmesg_component *dmesg_comp = msg_iter->dmesg_comp;
 470
 471         *new_start = line;
 472
 473         if (dmesg_comp->params.no_timestamp) {
 474                 goto skip_ts;
 475         }
 476
 477         /* Extract time from input line */
 478         if (sscanf(line, "[%lu.%lu] ", &sec, &usec) == 2) {
 479                 ts = (uint64_t) sec * USEC_PER_SEC + (uint64_t) usec;
 480
 481                 /*
 482                  * The clock class we use has a 1 GHz frequency: convert
 483                  * from µs to ns.
 484                  */
 485                 ts *= NSEC_PER_USEC;
 486                 has_timestamp = true;
 487         } else if (sscanf(line, "[%u-%u-%u %u:%u:%lu.%lu] ",
 488                         &year, &mon, &mday, &hour, &min,
 489                         &sec, &msec) == 7) {
 490                 time_t ep_sec;
 491                 struct tm ti;
 492
 493                 memset(&ti, 0, sizeof(ti));
 494                 ti.tm_year = year - 1900;       /* From 1900 */
 495                 ti.tm_mon = mon - 1;            /* 0 to 11 */
 496                 ti.tm_mday = mday;
 497                 ti.tm_hour = hour;
 498                 ti.tm_min = min;
 499                 ti.tm_sec = sec;
 500
 501                 ep_sec = bt_timegm(&ti);
 502                 if (ep_sec != (time_t) -1) {
 503                         ts = (uint64_t) ep_sec * NSEC_PER_SEC
 504                                 + (uint64_t) msec * NSEC_PER_MSEC;
 505                 }
 506
 507                 has_timestamp = true;
 508         }
 509
 510         if (has_timestamp) {
 511                 /* Set new start for the message portion of the line */
 512                 *new_start = strchr(line, ']');
 513                 BT_ASSERT(*new_start);
 514                 (*new_start)++;
 515
 516                 if ((*new_start)[0] == ' ') {
 517                         (*new_start)++;
 518                 }
 519         }
 520
 521 skip_ts:
 522         /*
 523          * At this point, we know if the stream class's event header
 524          * field class should have a timestamp or not, so we can lazily
 525          * create the metadata, stream, and packet objects.
 526          */
 527         ret = try_create_meta_stream_packet(dmesg_comp, has_timestamp);
 528         if (ret) {
 529                 /* try_create_meta_stream_packet() logs errors */
 530                 goto error;
 531         }
 532
 533         if (dmesg_comp->clock_class) {
 534                 msg = bt_message_event_create_with_default_clock_snapshot(
 535                         msg_iter->pc_msg_iter,
 536                         dmesg_comp->event_class, dmesg_comp->packet, ts);
 537                 msg_iter->last_clock_value = ts;
 538         } else {
 539                 msg = bt_message_event_create(msg_iter->pc_msg_iter,
 540                         dmesg_comp->event_class, dmesg_comp->packet);
 541         }
 542
 543         if (!msg) {
 544                 BT_COMP_LOGE_STR("Cannot create event message.");
 545                 goto error;
 546         }
 547
 548         event = bt_message_event_borrow_event(msg);
 549         BT_ASSERT(event);
 550         goto end;
 551
 552 error:
 553         BT_MESSAGE_PUT_REF_AND_RESET(msg);
 554
 555 end:
 556         return msg;
 557 }
 558
 559 static
 560 int fill_event_payload_from_line(struct dmesg_component *dmesg_comp,
 561                 const char *line, bt_event *event)
 562 {
 563         bt_field *ep_field = NULL;
 564         bt_field *str_field = NULL;
 565         size_t len;
 566         int ret;
 567
 568         ep_field = bt_event_borrow_payload_field(event);
 569         BT_ASSERT(ep_field);
 570         str_field = bt_field_structure_borrow_member_field_by_index(
 571                 ep_field, 0);
 572         if (!str_field) {
 573                 BT_COMP_LOGE_STR("Cannot borrow `timestamp` field from event payload structure field.");
 574                 goto error;
 575         }
 576
 577         len = strlen(line);
 578         if (line[len - 1] == '\n') {
 579                 /* Do not include the newline character in the payload */
 580                 len--;
 581         }
 582
 583         ret = bt_field_string_clear(str_field);
 584         if (ret) {
 585                 BT_COMP_LOGE_STR("Cannot clear string field object.");
 586                 goto error;
 587         }
 588
 589         ret = bt_field_string_append_with_length(str_field, line, len);
 590         if (ret) {
 591                 BT_COMP_LOGE("Cannot append value to string field object: "
 592                         "len=%zu", len);
 593                 goto error;
 594         }
 595
 596         goto end;
 597
 598 error:
 599         ret = -1;
 600
 601 end:
 602         return ret;
 603 }
 604
 605 static
 606 bt_message *create_msg_from_line(
 607                 struct dmesg_msg_iter *dmesg_msg_iter, const char *line)
 608 {
 609         struct dmesg_component *dmesg_comp = dmesg_msg_iter->dmesg_comp;
 610         bt_event *event = NULL;
 611         bt_message *msg = NULL;
 612         const char *new_start;
 613         int ret;
 614
 615         msg = create_init_event_msg_from_line(dmesg_msg_iter,
 616                 line, &new_start);
 617         if (!msg) {
 618                 BT_COMP_LOGE_STR("Cannot create and initialize event message from line.");
 619                 goto error;
 620         }
 621
 622         event = bt_message_event_borrow_event(msg);
 623         BT_ASSERT(event);
 624         ret = fill_event_payload_from_line(dmesg_comp, new_start, event);
 625         if (ret) {
 626                 BT_COMP_LOGE("Cannot fill event payload field from line: "
 627                         "ret=%d", ret);
 628                 goto error;
 629         }
 630
 631         goto end;
 632
 633 error:
 634         BT_MESSAGE_PUT_REF_AND_RESET(msg);
 635
 636 end:
 637         return msg;
 638 }
 639
 640 static
 641 void destroy_dmesg_msg_iter(struct dmesg_msg_iter *dmesg_msg_iter)
 642 {
 643         struct dmesg_component *dmesg_comp = dmesg_msg_iter->dmesg_comp;
 644
 645         if (!dmesg_msg_iter) {
 646                 return;
 647         }
 648
 649         if (dmesg_msg_iter->fp && dmesg_msg_iter->fp != stdin) {
 650                 if (fclose(dmesg_msg_iter->fp)) {
 651                         BT_COMP_LOGE_ERRNO("Cannot close input file", ".");
 652                 }
 653         }
 654
 655         bt_message_put_ref(dmesg_msg_iter->tmp_event_msg);
 656         free(dmesg_msg_iter->linebuf);
 657         g_free(dmesg_msg_iter);
 658 }
 659
 660
 661
 662 BT_HIDDEN
 663 bt_self_message_iterator_status dmesg_msg_iter_init(
 664                 bt_self_message_iterator *self_msg_iter,
 665                 bt_self_component_source *self_comp,
 666                 bt_self_component_port_output *self_port)
 667 {
 668         struct dmesg_component *dmesg_comp = bt_self_component_get_data(
 669                 bt_self_component_source_as_self_component(self_comp));
 670         struct dmesg_msg_iter *dmesg_msg_iter =
 671                 g_new0(struct dmesg_msg_iter, 1);
 672         bt_self_message_iterator_status status =
 673                 BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 674
 675         if (!dmesg_msg_iter) {
 676                 BT_COMP_LOGE_STR("Failed to allocate on dmesg message iterator structure.");
 677                 goto error;
 678         }
 679
 680         BT_ASSERT(dmesg_comp);
 681         dmesg_msg_iter->dmesg_comp = dmesg_comp;
 682         dmesg_msg_iter->pc_msg_iter = self_msg_iter;
 683
 684         if (dmesg_comp->params.read_from_stdin) {
 685                 dmesg_msg_iter->fp = stdin;
 686         } else {
 687                 dmesg_msg_iter->fp = fopen(dmesg_comp->params.path->str, "r");
 688                 if (!dmesg_msg_iter->fp) {
 689                         BT_COMP_LOGE_ERRNO("Cannot open input file in read mode", ": path=\"%s\"",
 690                                 dmesg_comp->params.path->str);
 691                         goto error;
 692                 }
 693         }
 694
 695         bt_self_message_iterator_set_data(self_msg_iter,
 696                 dmesg_msg_iter);
 697         goto end;
 698
 699 error:
 700         destroy_dmesg_msg_iter(dmesg_msg_iter);
 701         bt_self_message_iterator_set_data(self_msg_iter, NULL);
 702         if (status >= 0) {
 703                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_ERROR;
 704         }
 705
 706 end:
 707         return status;
 708 }
 709
 710 BT_HIDDEN
 711 void dmesg_msg_iter_finalize(
 712                 bt_self_message_iterator *priv_msg_iter)
 713 {
 714         destroy_dmesg_msg_iter(bt_self_message_iterator_get_data(
 715                 priv_msg_iter));
 716 }
 717
 718 static
 719 bt_self_message_iterator_status dmesg_msg_iter_next_one(
 720                 struct dmesg_msg_iter *dmesg_msg_iter,
 721                 bt_message **msg)
 722 {
 723         ssize_t len;
 724         struct dmesg_component *dmesg_comp;
 725         bt_self_message_iterator_status status =
 726                 BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 727
 728         BT_ASSERT(dmesg_msg_iter);
 729         dmesg_comp = dmesg_msg_iter->dmesg_comp;
 730         BT_ASSERT(dmesg_comp);
 731
 732         if (dmesg_msg_iter->state == STATE_DONE) {
 733                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_END;
 734                 goto end;
 735         }
 736
 737         if (dmesg_msg_iter->tmp_event_msg ||
 738                         dmesg_msg_iter->state == STATE_EMIT_PACKET_END ||
 739                         dmesg_msg_iter->state == STATE_EMIT_STREAM_ACTIVITY_END ||
 740                         dmesg_msg_iter->state == STATE_EMIT_STREAM_END) {
 741                 goto handle_state;
 742         }
 743
 744         while (true) {
 745                 const char *ch;
 746                 bool only_spaces = true;
 747
 748                 len = bt_getline(&dmesg_msg_iter->linebuf,
 749                         &dmesg_msg_iter->linebuf_len, dmesg_msg_iter->fp);
 750                 if (len < 0) {
 751                         if (errno == EINVAL) {
 752                                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_ERROR;
 753                         } else if (errno == ENOMEM) {
 754                                 status =
 755                                         BT_SELF_MESSAGE_ITERATOR_STATUS_NOMEM;
 756                         } else {
 757                                 if (dmesg_msg_iter->state == STATE_EMIT_STREAM_BEGINNING) {
 758                                         /* Stream did not even begin */
 759                                         status = BT_SELF_MESSAGE_ITERATOR_STATUS_END;
 760                                         goto end;
 761                                 } else {
 762                                         /* End current packet now */
 763                                         dmesg_msg_iter->state =
 764                                                 STATE_EMIT_PACKET_END;
 765                                         goto handle_state;
 766                                 }
 767                         }
 768
 769                         goto end;
 770                 }
 771
 772                 BT_ASSERT(dmesg_msg_iter->linebuf);
 773
 774                 /* Ignore empty lines, once trimmed */
 775                 for (ch = dmesg_msg_iter->linebuf; *ch != '\0'; ch++) {
 776                         if (!isspace(*ch)) {
 777                                 only_spaces = false;
 778                                 break;
 779                         }
 780                 }
 781
 782                 if (!only_spaces) {
 783                         break;
 784                 }
 785         }
 786
 787         dmesg_msg_iter->tmp_event_msg = create_msg_from_line(
 788                 dmesg_msg_iter, dmesg_msg_iter->linebuf);
 789         if (!dmesg_msg_iter->tmp_event_msg) {
 790                 BT_COMP_LOGE("Cannot create event message from line: "
 791                         "dmesg-comp-addr=%p, line=\"%s\"", dmesg_comp,
 792                         dmesg_msg_iter->linebuf);
 793                 goto end;
 794         }
 795
 796 handle_state:
 797         BT_ASSERT(dmesg_comp->trace);
 798
 799         switch (dmesg_msg_iter->state) {
 800         case STATE_EMIT_STREAM_BEGINNING:
 801                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 802                 *msg = bt_message_stream_beginning_create(
 803                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 804                 dmesg_msg_iter->state = STATE_EMIT_STREAM_ACTIVITY_BEGINNING;
 805                 break;
 806         case STATE_EMIT_STREAM_ACTIVITY_BEGINNING:
 807                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 808                 *msg = bt_message_stream_activity_beginning_create(
 809                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 810                 dmesg_msg_iter->state = STATE_EMIT_PACKET_BEGINNING;
 811                 break;
 812         case STATE_EMIT_PACKET_BEGINNING:
 813                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 814
 815                 if (dmesg_comp->clock_class) {
 816                         *msg = bt_message_packet_beginning_create_with_default_clock_snapshot(
 817                                 dmesg_msg_iter->pc_msg_iter, dmesg_comp->packet,
 818                                 dmesg_msg_iter->last_clock_value);
 819                 } else {
 820                         *msg = bt_message_packet_beginning_create(
 821                                 dmesg_msg_iter->pc_msg_iter, dmesg_comp->packet);
 822                 }
 823
 824                 dmesg_msg_iter->state = STATE_EMIT_EVENT;
 825                 break;
 826         case STATE_EMIT_EVENT:
 827                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 828                 *msg = dmesg_msg_iter->tmp_event_msg;
 829                 dmesg_msg_iter->tmp_event_msg = NULL;
 830                 break;
 831         case STATE_EMIT_PACKET_END:
 832                 if (dmesg_comp->clock_class) {
 833                         *msg = bt_message_packet_end_create_with_default_clock_snapshot(
 834                                 dmesg_msg_iter->pc_msg_iter, dmesg_comp->packet,
 835                                 dmesg_msg_iter->last_clock_value);
 836                 } else {
 837                         *msg = bt_message_packet_end_create(
 838                                 dmesg_msg_iter->pc_msg_iter, dmesg_comp->packet);
 839                 }
 840
 841                 dmesg_msg_iter->state = STATE_EMIT_STREAM_ACTIVITY_END;
 842                 break;
 843         case STATE_EMIT_STREAM_ACTIVITY_END:
 844                 *msg = bt_message_stream_activity_end_create(
 845                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 846                 dmesg_msg_iter->state = STATE_EMIT_STREAM_END;
 847                 break;
 848         case STATE_EMIT_STREAM_END:
 849                 *msg = bt_message_stream_end_create(
 850                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 851                 dmesg_msg_iter->state = STATE_DONE;
 852                 break;
 853         default:
 854                 break;
 855         }
 856
 857         if (!*msg) {
 858                 BT_COMP_LOGE("Cannot create message: dmesg-comp-addr=%p",
 859                         dmesg_comp);
 860                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_ERROR;
 861         }
 862
 863 end:
 864         return status;
 865 }
 866
 867 BT_HIDDEN
 868 bt_self_message_iterator_status dmesg_msg_iter_next(
 869                 bt_self_message_iterator *self_msg_iter,
 870                 bt_message_array_const msgs, uint64_t capacity,
 871                 uint64_t *count)
 872 {
 873         struct dmesg_msg_iter *dmesg_msg_iter =
 874                 bt_self_message_iterator_get_data(
 875                         self_msg_iter);
 876         bt_self_message_iterator_status status =
 877                 BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 878         uint64_t i = 0;
 879
 880         while (i < capacity &&
 881                         status == BT_SELF_MESSAGE_ITERATOR_STATUS_OK) {
 882                 bt_message *priv_msg = NULL;
 883
 884                 status = dmesg_msg_iter_next_one(dmesg_msg_iter,
 885                         &priv_msg);
 886                 msgs[i] = priv_msg;
 887                 if (status == BT_SELF_MESSAGE_ITERATOR_STATUS_OK) {
 888                         i++;
 889                 }
 890         }
 891
 892         if (i > 0) {
 893                 /*
 894                  * Even if dmesg_msg_iter_next_one() returned
 895                  * something else than
 896                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK, we
 897                  * accumulated message objects in the output
 898                  * message array, so we need to return
 899                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK so that they
 900                  * are transfered to downstream. This other status
 901                  * occurs again the next time muxer_msg_iter_do_next()
 902                  * is called, possibly without any accumulated
 903                  * message, in which case we'll return it.
 904                  */
 905                 *count = i;
 906                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 907         }
 908
 909         return status;
 910 }
 911
 912 BT_HIDDEN
 913 bt_bool dmesg_msg_iter_can_seek_beginning(
 914                 bt_self_message_iterator *self_msg_iter)
 915 {
 916         struct dmesg_msg_iter *dmesg_msg_iter =
 917                 bt_self_message_iterator_get_data(self_msg_iter);
 918
 919         /* Can't seek the beginning of the standard input stream */
 920         return !dmesg_msg_iter->dmesg_comp->params.read_from_stdin;
 921 }
 922
 923 BT_HIDDEN
 924 bt_self_message_iterator_status dmesg_msg_iter_seek_beginning(
 925                 bt_self_message_iterator *self_msg_iter)
 926 {
 927         struct dmesg_msg_iter *dmesg_msg_iter =
 928                 bt_self_message_iterator_get_data(self_msg_iter);
 929
 930         BT_ASSERT(!dmesg_msg_iter->dmesg_comp->params.read_from_stdin);
 931
 932         BT_MESSAGE_PUT_REF_AND_RESET(dmesg_msg_iter->tmp_event_msg);
 933         dmesg_msg_iter->last_clock_value = 0;
 934         dmesg_msg_iter->state = STATE_EMIT_STREAM_BEGINNING;
 935         return BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 936 }