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