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 "logging/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         g_free(basename);
 300
 301         return ret;
 302 }
 303
 304 static
 305 int try_create_meta_stream(struct dmesg_component *dmesg_comp, bool has_ts)
 306 {
 307         int ret = 0;
 308
 309         if (dmesg_comp->trace) {
 310                 /* Already created */
 311                 goto end;
 312         }
 313
 314         ret = create_meta(dmesg_comp, has_ts);
 315         if (ret) {
 316                 BT_COMP_LOGE("Cannot create metadata objects: dmesg-comp-addr=%p",
 317                         dmesg_comp);
 318                 goto error;
 319         }
 320
 321         ret = create_stream_and_trace(dmesg_comp);
 322         if (ret) {
 323                 BT_COMP_LOGE("Cannot create stream object: "
 324                         "dmesg-comp-addr=%p", dmesg_comp);
 325                 goto error;
 326         }
 327
 328         goto end;
 329
 330 error:
 331         ret = -1;
 332
 333 end:
 334         return ret;
 335 }
 336
 337 static
 338 void destroy_dmesg_component(struct dmesg_component *dmesg_comp)
 339 {
 340         if (!dmesg_comp) {
 341                 return;
 342         }
 343
 344         if (dmesg_comp->params.path) {
 345                 g_string_free(dmesg_comp->params.path, TRUE);
 346         }
 347
 348         bt_trace_put_ref(dmesg_comp->trace);
 349         bt_stream_class_put_ref(dmesg_comp->stream_class);
 350         bt_event_class_put_ref(dmesg_comp->event_class);
 351         bt_stream_put_ref(dmesg_comp->stream);
 352         bt_clock_class_put_ref(dmesg_comp->clock_class);
 353         bt_trace_class_put_ref(dmesg_comp->trace_class);
 354         g_free(dmesg_comp);
 355 }
 356
 357 static
 358 bt_component_class_initialize_method_status create_port(
 359                 bt_self_component_source *self_comp)
 360 {
 361         bt_component_class_initialize_method_status status;
 362         bt_self_component_add_port_status add_port_status;
 363
 364         add_port_status = bt_self_component_source_add_output_port(self_comp,
 365                 "out", NULL, NULL);
 366         switch (add_port_status) {
 367         case BT_SELF_COMPONENT_ADD_PORT_STATUS_OK:
 368                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_OK;
 369                 break;
 370         case BT_SELF_COMPONENT_ADD_PORT_STATUS_ERROR:
 371                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_ERROR;
 372                 break;
 373         case BT_SELF_COMPONENT_ADD_PORT_STATUS_MEMORY_ERROR:
 374                 status = BT_COMPONENT_CLASS_INITIALIZE_METHOD_STATUS_MEMORY_ERROR;
 375                 break;
 376         default:
 377                 abort();
 378         }
 379
 380         return status;
 381 }
 382
 383 BT_HIDDEN
 384 bt_component_class_initialize_method_status dmesg_init(
 385                 bt_self_component_source *self_comp_src,
 386                 bt_self_component_source_configuration *config,
 387                 bt_value *params, void *init_method_data)
 388 {
 389         int ret = 0;
 390         struct dmesg_component *dmesg_comp = g_new0(struct dmesg_component, 1);
 391         bt_component_class_initialize_method_status status =
 392                 BT_COMPONENT_CLASS_INITIALIZE_METHOD_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_COMPONENT_CLASS_INITIALIZE_METHOD_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_COMPONENT_CLASS_INITIALIZE_METHOD_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 and stream objects.
 526          */
 527         ret = try_create_meta_stream(dmesg_comp, has_timestamp);
 528         if (ret) {
 529                 /* try_create_meta_stream() 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->stream, 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->stream);
 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         bt_field_string_clear(str_field);
 584         ret = bt_field_string_append_with_length(str_field, line, len);
 585         if (ret) {
 586                 BT_COMP_LOGE("Cannot append value to string field object: "
 587                         "len=%zu", len);
 588                 goto error;
 589         }
 590
 591         goto end;
 592
 593 error:
 594         ret = -1;
 595
 596 end:
 597         return ret;
 598 }
 599
 600 static
 601 bt_message *create_msg_from_line(
 602                 struct dmesg_msg_iter *dmesg_msg_iter, const char *line)
 603 {
 604         struct dmesg_component *dmesg_comp = dmesg_msg_iter->dmesg_comp;
 605         bt_event *event = NULL;
 606         bt_message *msg = NULL;
 607         const char *new_start;
 608         int ret;
 609
 610         msg = create_init_event_msg_from_line(dmesg_msg_iter,
 611                 line, &new_start);
 612         if (!msg) {
 613                 BT_COMP_LOGE_STR("Cannot create and initialize event message from line.");
 614                 goto error;
 615         }
 616
 617         event = bt_message_event_borrow_event(msg);
 618         BT_ASSERT(event);
 619         ret = fill_event_payload_from_line(dmesg_comp, new_start, event);
 620         if (ret) {
 621                 BT_COMP_LOGE("Cannot fill event payload field from line: "
 622                         "ret=%d", ret);
 623                 goto error;
 624         }
 625
 626         goto end;
 627
 628 error:
 629         BT_MESSAGE_PUT_REF_AND_RESET(msg);
 630
 631 end:
 632         return msg;
 633 }
 634
 635 static
 636 void destroy_dmesg_msg_iter(struct dmesg_msg_iter *dmesg_msg_iter)
 637 {
 638         struct dmesg_component *dmesg_comp;
 639
 640         if (!dmesg_msg_iter) {
 641                 return;
 642         }
 643
 644         dmesg_comp = dmesg_msg_iter->dmesg_comp;
 645
 646         if (dmesg_msg_iter->fp && dmesg_msg_iter->fp != stdin) {
 647                 if (fclose(dmesg_msg_iter->fp)) {
 648                         BT_COMP_LOGE_ERRNO("Cannot close input file", ".");
 649                 }
 650         }
 651
 652         bt_message_put_ref(dmesg_msg_iter->tmp_event_msg);
 653         free(dmesg_msg_iter->linebuf);
 654         g_free(dmesg_msg_iter);
 655 }
 656
 657
 658
 659 BT_HIDDEN
 660 bt_component_class_message_iterator_initialize_method_status dmesg_msg_iter_init(
 661                 bt_self_message_iterator *self_msg_iter,
 662                 bt_self_message_iterator_configuration *config,
 663                 bt_self_component_source *self_comp,
 664                 bt_self_component_port_output *self_port)
 665 {
 666         struct dmesg_component *dmesg_comp = bt_self_component_get_data(
 667                 bt_self_component_source_as_self_component(self_comp));
 668         struct dmesg_msg_iter *dmesg_msg_iter =
 669                 g_new0(struct dmesg_msg_iter, 1);
 670         bt_component_class_message_iterator_initialize_method_status status =
 671                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INITIALIZE_METHOD_STATUS_OK;
 672
 673         if (!dmesg_msg_iter) {
 674                 BT_COMP_LOGE_STR("Failed to allocate on dmesg message iterator structure.");
 675                 goto error;
 676         }
 677
 678         BT_ASSERT(dmesg_comp);
 679         dmesg_msg_iter->dmesg_comp = dmesg_comp;
 680         dmesg_msg_iter->pc_msg_iter = self_msg_iter;
 681
 682         if (dmesg_comp->params.read_from_stdin) {
 683                 dmesg_msg_iter->fp = stdin;
 684         } else {
 685                 dmesg_msg_iter->fp = fopen(dmesg_comp->params.path->str, "r");
 686                 if (!dmesg_msg_iter->fp) {
 687                         BT_COMP_LOGE_ERRNO("Cannot open input file in read mode", ": path=\"%s\"",
 688                                 dmesg_comp->params.path->str);
 689                         goto error;
 690                 }
 691         }
 692
 693         bt_self_message_iterator_set_data(self_msg_iter,
 694                 dmesg_msg_iter);
 695         goto end;
 696
 697 error:
 698         destroy_dmesg_msg_iter(dmesg_msg_iter);
 699         bt_self_message_iterator_set_data(self_msg_iter, NULL);
 700         if (status >= 0) {
 701                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INITIALIZE_METHOD_STATUS_ERROR;
 702         }
 703
 704 end:
 705         return status;
 706 }
 707
 708 BT_HIDDEN
 709 void dmesg_msg_iter_finalize(
 710                 bt_self_message_iterator *priv_msg_iter)
 711 {
 712         destroy_dmesg_msg_iter(bt_self_message_iterator_get_data(
 713                 priv_msg_iter));
 714 }
 715
 716 static
 717 bt_component_class_message_iterator_next_method_status dmesg_msg_iter_next_one(
 718                 struct dmesg_msg_iter *dmesg_msg_iter,
 719                 bt_message **msg)
 720 {
 721         ssize_t len;
 722         struct dmesg_component *dmesg_comp;
 723         bt_component_class_message_iterator_next_method_status status =
 724                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 725
 726         BT_ASSERT(dmesg_msg_iter);
 727         dmesg_comp = dmesg_msg_iter->dmesg_comp;
 728         BT_ASSERT(dmesg_comp);
 729
 730         if (dmesg_msg_iter->state == STATE_DONE) {
 731                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_END;
 732                 goto end;
 733         }
 734
 735         if (dmesg_msg_iter->tmp_event_msg ||
 736                         dmesg_msg_iter->state == STATE_EMIT_STREAM_END) {
 737                 goto handle_state;
 738         }
 739
 740         while (true) {
 741                 const char *ch;
 742                 bool only_spaces = true;
 743
 744                 len = bt_getline(&dmesg_msg_iter->linebuf,
 745                         &dmesg_msg_iter->linebuf_len, dmesg_msg_iter->fp);
 746                 if (len < 0) {
 747                         if (errno == EINVAL) {
 748                                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 749                         } else if (errno == ENOMEM) {
 750                                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_MEMORY_ERROR;
 751                         } else {
 752                                 if (dmesg_msg_iter->state == STATE_EMIT_STREAM_BEGINNING) {
 753                                         /* Stream did not even begin */
 754                                         status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_END;
 755                                         goto end;
 756                                 } else {
 757                                         /* End stream now */
 758                                         dmesg_msg_iter->state =
 759                                                 STATE_EMIT_STREAM_END;
 760                                         goto handle_state;
 761                                 }
 762                         }
 763
 764                         goto end;
 765                 }
 766
 767                 BT_ASSERT(dmesg_msg_iter->linebuf);
 768
 769                 /* Ignore empty lines, once trimmed */
 770                 for (ch = dmesg_msg_iter->linebuf; *ch != '\0'; ch++) {
 771                         if (!isspace(*ch)) {
 772                                 only_spaces = false;
 773                                 break;
 774                         }
 775                 }
 776
 777                 if (!only_spaces) {
 778                         break;
 779                 }
 780         }
 781
 782         dmesg_msg_iter->tmp_event_msg = create_msg_from_line(
 783                 dmesg_msg_iter, dmesg_msg_iter->linebuf);
 784         if (!dmesg_msg_iter->tmp_event_msg) {
 785                 BT_COMP_LOGE("Cannot create event message from line: "
 786                         "dmesg-comp-addr=%p, line=\"%s\"", dmesg_comp,
 787                         dmesg_msg_iter->linebuf);
 788                 goto end;
 789         }
 790
 791 handle_state:
 792         BT_ASSERT(dmesg_comp->trace);
 793
 794         switch (dmesg_msg_iter->state) {
 795         case STATE_EMIT_STREAM_BEGINNING:
 796                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 797                 *msg = bt_message_stream_beginning_create(
 798                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 799                 dmesg_msg_iter->state = STATE_EMIT_EVENT;
 800                 break;
 801         case STATE_EMIT_EVENT:
 802                 BT_ASSERT(dmesg_msg_iter->tmp_event_msg);
 803                 *msg = dmesg_msg_iter->tmp_event_msg;
 804                 dmesg_msg_iter->tmp_event_msg = NULL;
 805                 break;
 806         case STATE_EMIT_STREAM_END:
 807                 *msg = bt_message_stream_end_create(
 808                         dmesg_msg_iter->pc_msg_iter, dmesg_comp->stream);
 809                 dmesg_msg_iter->state = STATE_DONE;
 810                 break;
 811         default:
 812                 break;
 813         }
 814
 815         if (!*msg) {
 816                 BT_COMP_LOGE("Cannot create message: dmesg-comp-addr=%p",
 817                         dmesg_comp);
 818                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
 819         }
 820
 821 end:
 822         return status;
 823 }
 824
 825 BT_HIDDEN
 826 bt_component_class_message_iterator_next_method_status dmesg_msg_iter_next(
 827                 bt_self_message_iterator *self_msg_iter,
 828                 bt_message_array_const msgs, uint64_t capacity,
 829                 uint64_t *count)
 830 {
 831         struct dmesg_msg_iter *dmesg_msg_iter =
 832                 bt_self_message_iterator_get_data(
 833                         self_msg_iter);
 834         bt_component_class_message_iterator_next_method_status status =
 835                 BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 836         uint64_t i = 0;
 837
 838         while (i < capacity &&
 839                         status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
 840                 bt_message *priv_msg = NULL;
 841
 842                 status = dmesg_msg_iter_next_one(dmesg_msg_iter,
 843                         &priv_msg);
 844                 msgs[i] = priv_msg;
 845                 if (status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
 846                         i++;
 847                 }
 848         }
 849
 850         if (i > 0) {
 851                 /*
 852                  * Even if dmesg_msg_iter_next_one() returned
 853                  * something else than
 854                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK, we
 855                  * accumulated message objects in the output
 856                  * message array, so we need to return
 857                  * BT_SELF_MESSAGE_ITERATOR_STATUS_OK so that they
 858                  * are transfered to downstream. This other status
 859                  * occurs again the next time muxer_msg_iter_do_next()
 860                  * is called, possibly without any accumulated
 861                  * message, in which case we'll return it.
 862                  */
 863                 *count = i;
 864                 status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
 865         }
 866
 867         return status;
 868 }
 869
 870 BT_HIDDEN
 871 bt_component_class_message_iterator_can_seek_beginning_method_status
 872 dmesg_msg_iter_can_seek_beginning(
 873                 bt_self_message_iterator *self_msg_iter, bt_bool *can_seek)
 874 {
 875         struct dmesg_msg_iter *dmesg_msg_iter =
 876                 bt_self_message_iterator_get_data(self_msg_iter);
 877
 878         /* Can't seek the beginning of the standard input stream */
 879         *can_seek = !dmesg_msg_iter->dmesg_comp->params.read_from_stdin;
 880
 881         return BT_COMPONENT_CLASS_MESSAGE_ITERATOR_CAN_SEEK_BEGINNING_METHOD_STATUS_OK;
 882 }
 883
 884 BT_HIDDEN
 885 bt_component_class_message_iterator_seek_beginning_method_status
 886 dmesg_msg_iter_seek_beginning(
 887                 bt_self_message_iterator *self_msg_iter)
 888 {
 889         struct dmesg_msg_iter *dmesg_msg_iter =
 890                 bt_self_message_iterator_get_data(self_msg_iter);
 891
 892         BT_ASSERT(!dmesg_msg_iter->dmesg_comp->params.read_from_stdin);
 893
 894         BT_MESSAGE_PUT_REF_AND_RESET(dmesg_msg_iter->tmp_event_msg);
 895         dmesg_msg_iter->last_clock_value = 0;
 896         dmesg_msg_iter->state = STATE_EMIT_STREAM_BEGINNING;
 897         return BT_COMPONENT_CLASS_MESSAGE_ITERATOR_SEEK_BEGINNING_METHOD_STATUS_OK;
 898 }