src/plugins/ctf/fs-src/data-stream-file.c

   1 /*
   2  * Copyright 2016-2017 - Philippe Proulx <pproulx@efficios.com>
   3  * Copyright 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  * Copyright 2010-2011 - EfficiOS Inc. and Linux Foundation
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27 #include <stdint.h>
  28 #include <stdlib.h>
  29 #include <stdbool.h>
  30 #include <glib.h>
  31 #include <inttypes.h>
  32 #include "compat/mman.h"
  33 #include "compat/endian.h"
  34 #include <babeltrace2/babeltrace.h>
  35 #include "common/common.h"
  36 #include "file.h"
  37 #include "metadata.h"
  38 #include "../common/msg-iter/msg-iter.h"
  39 #include "common/assert.h"
  40 #include "data-stream-file.h"
  41 #include <string.h>
  42
  43 #define BT_LOG_TAG "PLUGIN/SRC.CTF.FS/DS"
  44 #include "logging.h"
  45
  46 static inline
  47 size_t remaining_mmap_bytes(struct ctf_fs_ds_file *ds_file)
  48 {
  49         return ds_file->mmap_len - ds_file->request_offset;
  50 }
  51
  52 static
  53 int ds_file_munmap(struct ctf_fs_ds_file *ds_file)
  54 {
  55         int ret = 0;
  56
  57         if (!ds_file || !ds_file->mmap_addr) {
  58                 goto end;
  59         }
  60
  61         if (bt_munmap(ds_file->mmap_addr, ds_file->mmap_len)) {
  62                 BT_LOGE_ERRNO("Cannot memory-unmap file",
  63                         ": address=%p, size=%zu, file_path=\"%s\", file=%p",
  64                         ds_file->mmap_addr, ds_file->mmap_len,
  65                         ds_file->file ? ds_file->file->path->str : "NULL",
  66                         ds_file->file ? ds_file->file->fp : NULL);
  67                 ret = -1;
  68                 goto end;
  69         }
  70
  71         ds_file->mmap_addr = NULL;
  72
  73 end:
  74         return ret;
  75 }
  76
  77 static
  78 enum bt_msg_iter_medium_status ds_file_mmap_next(
  79                 struct ctf_fs_ds_file *ds_file)
  80 {
  81         enum bt_msg_iter_medium_status ret =
  82                         BT_MSG_ITER_MEDIUM_STATUS_OK;
  83
  84         /* Unmap old region */
  85         if (ds_file->mmap_addr) {
  86                 if (ds_file_munmap(ds_file)) {
  87                         goto error;
  88                 }
  89
  90                 /*
  91                  * mmap_len is guaranteed to be page-aligned except on the
  92                  * last mapping where it may not be possible (since the file's
  93                  * size itself may not be a page multiple).
  94                  */
  95                 ds_file->mmap_offset += ds_file->mmap_len;
  96                 ds_file->request_offset = 0;
  97         }
  98
  99         ds_file->mmap_len = MIN(ds_file->file->size - ds_file->mmap_offset,
 100                         ds_file->mmap_max_len);
 101         if (ds_file->mmap_len == 0) {
 102                 ret = BT_MSG_ITER_MEDIUM_STATUS_EOF;
 103                 goto end;
 104         }
 105         /* Map new region */
 106         BT_ASSERT(ds_file->mmap_len);
 107         ds_file->mmap_addr = bt_mmap((void *) 0, ds_file->mmap_len,
 108                         PROT_READ, MAP_PRIVATE, fileno(ds_file->file->fp),
 109                         ds_file->mmap_offset);
 110         if (ds_file->mmap_addr == MAP_FAILED) {
 111                 BT_LOGE("Cannot memory-map address (size %zu) of file \"%s\" (%p) at offset %jd: %s",
 112                                 ds_file->mmap_len, ds_file->file->path->str,
 113                                 ds_file->file->fp, (intmax_t) ds_file->mmap_offset,
 114                                 strerror(errno));
 115                 goto error;
 116         }
 117
 118         goto end;
 119 error:
 120         ds_file_munmap(ds_file);
 121         ret = BT_MSG_ITER_MEDIUM_STATUS_ERROR;
 122 end:
 123         return ret;
 124 }
 125
 126 static
 127 enum bt_msg_iter_medium_status medop_request_bytes(
 128                 size_t request_sz, uint8_t **buffer_addr,
 129                 size_t *buffer_sz, void *data)
 130 {
 131         enum bt_msg_iter_medium_status status =
 132                 BT_MSG_ITER_MEDIUM_STATUS_OK;
 133         struct ctf_fs_ds_file *ds_file = data;
 134
 135         if (request_sz == 0) {
 136                 goto end;
 137         }
 138
 139         /* Check if we have at least one memory-mapped byte left */
 140         if (remaining_mmap_bytes(ds_file) == 0) {
 141                 /* Are we at the end of the file? */
 142                 if (ds_file->mmap_offset >= ds_file->file->size) {
 143                         BT_LOGD("Reached end of file \"%s\" (%p)",
 144                                 ds_file->file->path->str, ds_file->file->fp);
 145                         status = BT_MSG_ITER_MEDIUM_STATUS_EOF;
 146                         goto end;
 147                 }
 148
 149                 status = ds_file_mmap_next(ds_file);
 150                 switch (status) {
 151                 case BT_MSG_ITER_MEDIUM_STATUS_OK:
 152                         break;
 153                 case BT_MSG_ITER_MEDIUM_STATUS_EOF:
 154                         goto end;
 155                 default:
 156                         BT_LOGE("Cannot memory-map next region of file \"%s\" (%p)",
 157                                         ds_file->file->path->str,
 158                                         ds_file->file->fp);
 159                         goto error;
 160                 }
 161         }
 162
 163         *buffer_sz = MIN(remaining_mmap_bytes(ds_file), request_sz);
 164         *buffer_addr = ((uint8_t *) ds_file->mmap_addr) + ds_file->request_offset;
 165         ds_file->request_offset += *buffer_sz;
 166         goto end;
 167
 168 error:
 169         status = BT_MSG_ITER_MEDIUM_STATUS_ERROR;
 170
 171 end:
 172         return status;
 173 }
 174
 175 static
 176 bt_stream *medop_borrow_stream(bt_stream_class *stream_class, int64_t stream_id,
 177                 void *data)
 178 {
 179         struct ctf_fs_ds_file *ds_file = data;
 180         bt_stream_class *ds_file_stream_class;
 181         bt_stream *stream = NULL;
 182
 183         ds_file_stream_class = bt_stream_borrow_class(
 184                 ds_file->stream);
 185
 186         if (stream_class != ds_file_stream_class) {
 187                 /*
 188                  * Not supported: two packets described by two different
 189                  * stream classes within the same data stream file.
 190                  */
 191                 goto end;
 192         }
 193
 194         stream = ds_file->stream;
 195
 196 end:
 197         return stream;
 198 }
 199
 200 static
 201 enum bt_msg_iter_medium_status medop_seek(enum bt_msg_iter_seek_whence whence,
 202                 off_t offset, void *data)
 203 {
 204         enum bt_msg_iter_medium_status ret =
 205                         BT_MSG_ITER_MEDIUM_STATUS_OK;
 206         struct ctf_fs_ds_file *ds_file = data;
 207         off_t file_size = ds_file->file->size;
 208
 209         if (whence != BT_MSG_ITER_SEEK_WHENCE_SET ||
 210                 offset < 0 || offset > file_size) {
 211                 BT_LOGE("Invalid medium seek request: whence=%d, offset=%jd, "
 212                                 "file-size=%jd", (int) whence, offset,
 213                                 file_size);
 214                 ret = BT_MSG_ITER_MEDIUM_STATUS_INVAL;
 215                 goto end;
 216         }
 217
 218         /*
 219          * Determine whether or not the destination is contained within the
 220          * current mapping.
 221          */
 222         if (ds_file->mmap_addr && (offset < ds_file->mmap_offset ||
 223                         offset >= ds_file->mmap_offset + ds_file->mmap_len)) {
 224                 int unmap_ret;
 225                 off_t offset_in_mapping = offset % bt_common_get_page_size();
 226
 227                 BT_LOGD("Medium seek request cannot be accomodated by the current "
 228                                 "file mapping: offset=%jd, mmap-offset=%jd, "
 229                                 "mmap-len=%zu", offset, ds_file->mmap_offset,
 230                                 ds_file->mmap_len);
 231                 unmap_ret = ds_file_munmap(ds_file);
 232                 if (unmap_ret) {
 233                         ret = BT_MSG_ITER_MEDIUM_STATUS_ERROR;
 234                         goto end;
 235                 }
 236
 237                 ds_file->mmap_offset = offset - offset_in_mapping;
 238                 ds_file->request_offset = offset_in_mapping;
 239                 ret = ds_file_mmap_next(ds_file);
 240                 if (ret != BT_MSG_ITER_MEDIUM_STATUS_OK) {
 241                         goto end;
 242                 }
 243         } else {
 244                 ds_file->request_offset = offset - ds_file->mmap_offset;
 245         }
 246
 247         ds_file->end_reached = (offset == file_size);
 248 end:
 249         return ret;
 250 }
 251
 252 BT_HIDDEN
 253 struct bt_msg_iter_medium_ops ctf_fs_ds_file_medops = {
 254         .request_bytes = medop_request_bytes,
 255         .borrow_stream = medop_borrow_stream,
 256         .seek = medop_seek,
 257 };
 258
 259 static
 260 int convert_cycles_to_ns(struct ctf_clock_class *clock_class,
 261                 uint64_t cycles, int64_t *ns)
 262 {
 263         return bt_util_clock_cycles_to_ns_from_origin(cycles,
 264                         clock_class->frequency, clock_class->offset_seconds,
 265                         clock_class->offset_cycles, ns);
 266 }
 267
 268 static
 269 struct ctf_fs_ds_index *build_index_from_idx_file(
 270                 struct ctf_fs_ds_file *ds_file)
 271 {
 272         int ret;
 273         gchar *directory = NULL;
 274         gchar *basename = NULL;
 275         GString *index_basename = NULL;
 276         gchar *index_file_path = NULL;
 277         GMappedFile *mapped_file = NULL;
 278         gsize filesize;
 279         const char *mmap_begin = NULL, *file_pos = NULL;
 280         const struct ctf_packet_index_file_hdr *header = NULL;
 281         struct ctf_fs_ds_index *index = NULL;
 282         struct ctf_fs_ds_index_entry *index_entry = NULL;
 283         uint64_t total_packets_size = 0;
 284         size_t file_index_entry_size;
 285         size_t file_entry_count;
 286         size_t i;
 287         struct ctf_stream_class *sc;
 288         struct bt_msg_iter_packet_properties props;
 289
 290         BT_LOGI("Building index from .idx file of stream file %s",
 291                         ds_file->file->path->str);
 292         ret = bt_msg_iter_get_packet_properties(ds_file->msg_iter, &props);
 293         if (ret) {
 294                 BT_LOGI_STR("Cannot read first packet's header and context fields.");
 295                 goto error;
 296         }
 297
 298         sc = ctf_trace_class_borrow_stream_class_by_id(ds_file->metadata->tc,
 299                 props.stream_class_id);
 300         BT_ASSERT(sc);
 301         if (!sc->default_clock_class) {
 302                 BT_LOGI_STR("Cannot find stream class's default clock class.");
 303                 goto error;
 304         }
 305
 306         /* Look for index file in relative path index/name.idx. */
 307         basename = g_path_get_basename(ds_file->file->path->str);
 308         if (!basename) {
 309                 BT_LOGE("Cannot get the basename of datastream file %s",
 310                                 ds_file->file->path->str);
 311                 goto error;
 312         }
 313
 314         directory = g_path_get_dirname(ds_file->file->path->str);
 315         if (!directory) {
 316                 BT_LOGE("Cannot get dirname of datastream file %s",
 317                                 ds_file->file->path->str);
 318                 goto error;
 319         }
 320
 321         index_basename = g_string_new(basename);
 322         if (!index_basename) {
 323                 BT_LOGE_STR("Cannot allocate index file basename string");
 324                 goto error;
 325         }
 326
 327         g_string_append(index_basename, ".idx");
 328         index_file_path = g_build_filename(directory, "index",
 329                         index_basename->str, NULL);
 330         mapped_file = g_mapped_file_new(index_file_path, FALSE, NULL);
 331         if (!mapped_file) {
 332                 BT_LOGD("Cannot create new mapped file %s",
 333                                 index_file_path);
 334                 goto error;
 335         }
 336
 337         /*
 338          * The g_mapped_file API limits us to 4GB files on 32-bit.
 339          * Traces with such large indexes have never been seen in the wild,
 340          * but this would need to be adjusted to support them.
 341          */
 342         filesize = g_mapped_file_get_length(mapped_file);
 343         if (filesize < sizeof(*header)) {
 344                 BT_LOGW("Invalid LTTng trace index file: "
 345                         "file size (%zu bytes) < header size (%zu bytes)",
 346                         filesize, sizeof(*header));
 347                 goto error;
 348         }
 349
 350         mmap_begin = g_mapped_file_get_contents(mapped_file);
 351         header = (struct ctf_packet_index_file_hdr *) mmap_begin;
 352
 353         file_pos = g_mapped_file_get_contents(mapped_file) + sizeof(*header);
 354         if (be32toh(header->magic) != CTF_INDEX_MAGIC) {
 355                 BT_LOGW_STR("Invalid LTTng trace index: \"magic\" field validation failed");
 356                 goto error;
 357         }
 358
 359         file_index_entry_size = be32toh(header->packet_index_len);
 360         file_entry_count = (filesize - sizeof(*header)) / file_index_entry_size;
 361         if ((filesize - sizeof(*header)) % file_index_entry_size) {
 362                 BT_LOGW("Invalid LTTng trace index: the index's size after the header "
 363                         "(%zu bytes) is not a multiple of the index entry size "
 364                         "(%zu bytes)", (filesize - sizeof(*header)),
 365                         sizeof(*header));
 366                 goto error;
 367         }
 368
 369         index = ctf_fs_ds_index_create();
 370         if (!index) {
 371                 goto error;
 372         }
 373
 374         for (i = 0; i < file_entry_count; i++) {
 375                 struct ctf_packet_index *file_index =
 376                                 (struct ctf_packet_index *) file_pos;
 377                 uint64_t packet_size = be64toh(file_index->packet_size);
 378
 379                 if (packet_size % CHAR_BIT) {
 380                         BT_LOGW("Invalid packet size encountered in LTTng trace index file");
 381                         goto error;
 382                 }
 383
 384                 index_entry = g_new0(struct ctf_fs_ds_index_entry, 1);
 385                 if (!index_entry) {
 386                         goto error;
 387                 }
 388
 389                 /* Convert size in bits to bytes. */
 390                 packet_size /= CHAR_BIT;
 391                 index_entry->packet_size = packet_size;
 392
 393                 index_entry->offset = be64toh(file_index->offset);
 394                 if (i != 0 && index_entry->offset < (index_entry - 1)->offset) {
 395                         BT_LOGW("Invalid, non-monotonic, packet offset encountered in LTTng trace index file: "
 396                                 "previous offset=%" PRIu64 ", current offset=%" PRIu64,
 397                                 (index_entry - 1)->offset, index_entry->offset);
 398                         goto error;
 399                 }
 400
 401                 index_entry->timestamp_begin = be64toh(file_index->timestamp_begin);
 402                 index_entry->timestamp_end = be64toh(file_index->timestamp_end);
 403                 if (index_entry->timestamp_end < index_entry->timestamp_begin) {
 404                         BT_LOGW("Invalid packet time bounds encountered in LTTng trace index file (begin > end): "
 405                                 "timestamp_begin=%" PRIu64 "timestamp_end=%" PRIu64,
 406                                 index_entry->timestamp_begin,
 407                                 index_entry->timestamp_end);
 408                         goto error;
 409                 }
 410
 411                 /* Convert the packet's bound to nanoseconds since Epoch. */
 412                 ret = convert_cycles_to_ns(sc->default_clock_class,
 413                                 index_entry->timestamp_begin,
 414                                 &index_entry->timestamp_begin_ns);
 415                 if (ret) {
 416                         BT_LOGI_STR("Failed to convert raw timestamp to nanoseconds since Epoch during index parsing");
 417                         goto error;
 418                 }
 419                 ret = convert_cycles_to_ns(sc->default_clock_class,
 420                                 index_entry->timestamp_end,
 421                                 &index_entry->timestamp_end_ns);
 422                 if (ret) {
 423                         BT_LOGI_STR("Failed to convert raw timestamp to nanoseconds since Epoch during LTTng trace index parsing");
 424                         goto error;
 425                 }
 426
 427                 total_packets_size += packet_size;
 428                 file_pos += file_index_entry_size;
 429
 430                 g_ptr_array_add(index->entries, index_entry);
 431         }
 432
 433         /* Validate that the index addresses the complete stream. */
 434         if (ds_file->file->size != total_packets_size) {
 435                 BT_LOGW("Invalid LTTng trace index file; indexed size != stream file size: "
 436                         "file-size=%" PRIu64 ", total-packets-size=%" PRIu64,
 437                         ds_file->file->size, total_packets_size);
 438                 goto error;
 439         }
 440 end:
 441         g_free(directory);
 442         g_free(basename);
 443         g_free(index_file_path);
 444         if (index_basename) {
 445                 g_string_free(index_basename, TRUE);
 446         }
 447         if (mapped_file) {
 448                 g_mapped_file_unref(mapped_file);
 449         }
 450         return index;
 451 error:
 452         ctf_fs_ds_index_destroy(index);
 453         g_free(index_entry);
 454         index = NULL;
 455         goto end;
 456 }
 457
 458 static
 459 int init_index_entry(struct ctf_fs_ds_index_entry *entry,
 460                 struct ctf_fs_ds_file *ds_file,
 461                 struct bt_msg_iter_packet_properties *props,
 462                 off_t packet_size, off_t packet_offset)
 463 {
 464         int ret = 0;
 465         struct ctf_stream_class *sc;
 466
 467         sc = ctf_trace_class_borrow_stream_class_by_id(ds_file->metadata->tc,
 468                 props->stream_class_id);
 469         BT_ASSERT(sc);
 470         BT_ASSERT(packet_offset >= 0);
 471         entry->offset = packet_offset;
 472         BT_ASSERT(packet_size >= 0);
 473         entry->packet_size = packet_size;
 474
 475         if (props->snapshots.beginning_clock != UINT64_C(-1)) {
 476                 /* Convert the packet's bound to nanoseconds since Epoch. */
 477                 ret = convert_cycles_to_ns(sc->default_clock_class,
 478                                            props->snapshots.beginning_clock,
 479                                            &entry->timestamp_begin_ns);
 480                 if (ret) {
 481                         BT_LOGI_STR("Failed to convert raw timestamp to nanoseconds since Epoch.");
 482                         goto end;
 483                 }
 484         } else {
 485                 entry->timestamp_begin_ns = UINT64_C(-1);
 486         }
 487
 488         if (props->snapshots.end_clock != UINT64_C(-1)) {
 489                 ret = convert_cycles_to_ns(sc->default_clock_class,
 490                                            props->snapshots.end_clock,
 491                                            &entry->timestamp_end_ns);
 492                 if (ret) {
 493                         BT_LOGI_STR("Failed to convert raw timestamp to nanoseconds since Epoch.");
 494                         goto end;
 495                 }
 496         } else {
 497                 entry->timestamp_end_ns = UINT64_C(-1);
 498         }
 499
 500 end:
 501         return ret;
 502 }
 503
 504 static
 505 struct ctf_fs_ds_index *build_index_from_stream_file(
 506                 struct ctf_fs_ds_file *ds_file)
 507 {
 508         int ret;
 509         struct ctf_fs_ds_index *index = NULL;
 510         enum bt_msg_iter_status iter_status = BT_MSG_ITER_STATUS_OK;
 511         off_t current_packet_offset_bytes = 0;
 512
 513         BT_LOGI("Indexing stream file %s", ds_file->file->path->str);
 514
 515         index = ctf_fs_ds_index_create();
 516         if (!index) {
 517                 goto error;
 518         }
 519
 520         do {
 521                 off_t current_packet_size_bytes;
 522                 struct ctf_fs_ds_index_entry *index_entry;
 523                 struct bt_msg_iter_packet_properties props;
 524
 525                 if (current_packet_offset_bytes < 0) {
 526                         BT_LOGE_STR("Cannot get the current packet's offset.");
 527                         goto error;
 528                 } else if (current_packet_offset_bytes > ds_file->file->size) {
 529                         BT_LOGE_STR("Unexpected current packet's offset (larger than file).");
 530                         goto error;
 531                 } else if (current_packet_offset_bytes == ds_file->file->size) {
 532                         /* No more data */
 533                         break;
 534                 }
 535
 536                 iter_status = bt_msg_iter_seek(ds_file->msg_iter,
 537                                 current_packet_offset_bytes);
 538                 if (iter_status != BT_MSG_ITER_STATUS_OK) {
 539                         goto error;
 540                 }
 541
 542                 iter_status = bt_msg_iter_get_packet_properties(
 543                         ds_file->msg_iter, &props);
 544                 if (iter_status != BT_MSG_ITER_STATUS_OK) {
 545                         goto error;
 546                 }
 547
 548                 if (props.exp_packet_total_size >= 0) {
 549                         current_packet_size_bytes =
 550                                 (uint64_t) props.exp_packet_total_size / 8;
 551                 } else {
 552                         current_packet_size_bytes = ds_file->file->size;
 553                 }
 554
 555                 if (current_packet_offset_bytes + current_packet_size_bytes >
 556                                 ds_file->file->size) {
 557                         BT_LOGW("Invalid packet size reported in file: stream=\"%s\", "
 558                                         "packet-offset=%jd, packet-size-bytes=%jd, "
 559                                         "file-size=%jd",
 560                                         ds_file->file->path->str,
 561                                         current_packet_offset_bytes,
 562                                         current_packet_size_bytes,
 563                                         ds_file->file->size);
 564                         goto error;
 565                 }
 566
 567                 index_entry = g_new0(struct ctf_fs_ds_index_entry, 1);
 568                 if (!index_entry) {
 569                         BT_LOGE_STR("Failed to allocate a new index entry.");
 570                         goto error;
 571                 }
 572
 573                 ret = init_index_entry(index_entry, ds_file, &props,
 574                         current_packet_size_bytes, current_packet_offset_bytes);
 575                 if (ret) {
 576                         g_free(index_entry);
 577                         goto error;
 578                 }
 579
 580                 g_ptr_array_add(index->entries, index_entry);
 581
 582                 current_packet_offset_bytes += current_packet_size_bytes;
 583                 BT_LOGD("Seeking to next packet: current-packet-offset=%jd, "
 584                         "next-packet-offset=%jd",
 585                         current_packet_offset_bytes - current_packet_size_bytes,
 586                         current_packet_offset_bytes);
 587
 588         } while (iter_status == BT_MSG_ITER_STATUS_OK);
 589
 590         if (iter_status != BT_MSG_ITER_STATUS_OK) {
 591                 goto error;
 592         }
 593
 594 end:
 595         return index;
 596
 597 error:
 598         ctf_fs_ds_index_destroy(index);
 599         index = NULL;
 600         goto end;
 601 }
 602
 603 BT_HIDDEN
 604 struct ctf_fs_ds_file *ctf_fs_ds_file_create(
 605                 struct ctf_fs_trace *ctf_fs_trace,
 606                 bt_self_message_iterator *pc_msg_iter,
 607                 struct bt_msg_iter *msg_iter,
 608                 bt_stream *stream, const char *path)
 609 {
 610         int ret;
 611         const size_t page_size = bt_common_get_page_size();
 612         struct ctf_fs_ds_file *ds_file = g_new0(struct ctf_fs_ds_file, 1);
 613
 614         if (!ds_file) {
 615                 goto error;
 616         }
 617
 618         ds_file->pc_msg_iter = pc_msg_iter;
 619         ds_file->file = ctf_fs_file_create();
 620         if (!ds_file->file) {
 621                 goto error;
 622         }
 623
 624         ds_file->stream = stream;
 625         bt_stream_get_ref(ds_file->stream);
 626         ds_file->metadata = ctf_fs_trace->metadata;
 627         g_string_assign(ds_file->file->path, path);
 628         ret = ctf_fs_file_open(ds_file->file, "rb");
 629         if (ret) {
 630                 goto error;
 631         }
 632
 633         ds_file->msg_iter = msg_iter;
 634         bt_msg_iter_set_medops_data(ds_file->msg_iter, ds_file);
 635         if (!ds_file->msg_iter) {
 636                 goto error;
 637         }
 638
 639         ds_file->mmap_max_len = page_size * 2048;
 640
 641         goto end;
 642
 643 error:
 644         /* Do not touch "borrowed" file. */
 645         ctf_fs_ds_file_destroy(ds_file);
 646         ds_file = NULL;
 647
 648 end:
 649         return ds_file;
 650 }
 651
 652 BT_HIDDEN
 653 struct ctf_fs_ds_index *ctf_fs_ds_file_build_index(
 654                 struct ctf_fs_ds_file *ds_file)
 655 {
 656         struct ctf_fs_ds_index *index;
 657
 658         index = build_index_from_idx_file(ds_file);
 659         if (index) {
 660                 goto end;
 661         }
 662
 663         BT_LOGI("Failed to build index from .index file; "
 664                 "falling back to stream indexing.");
 665         index = build_index_from_stream_file(ds_file);
 666 end:
 667         return index;
 668 }
 669
 670 BT_HIDDEN
 671 struct ctf_fs_ds_index *ctf_fs_ds_index_create()
 672 {
 673         struct ctf_fs_ds_index *index = g_new0(struct ctf_fs_ds_index, 1);
 674
 675         if (!index) {
 676                 BT_LOGE_STR("Failed to allocate index");
 677                 goto error;
 678         }
 679
 680         index->entries = g_ptr_array_new_with_free_func((GDestroyNotify) g_free);
 681         if (!index->entries) {
 682                 BT_LOGE("Failed to allocate index entries.");
 683                 goto error;
 684         }
 685
 686         goto end;
 687
 688 error:
 689         ctf_fs_ds_index_destroy(index);
 690         index = NULL;
 691 end:
 692         return index;
 693 }
 694
 695 BT_HIDDEN
 696 void ctf_fs_ds_file_destroy(struct ctf_fs_ds_file *ds_file)
 697 {
 698         if (!ds_file) {
 699                 return;
 700         }
 701
 702         bt_stream_put_ref(ds_file->stream);
 703         (void) ds_file_munmap(ds_file);
 704
 705         if (ds_file->file) {
 706                 ctf_fs_file_destroy(ds_file->file);
 707         }
 708
 709         g_free(ds_file);
 710 }
 711
 712 BT_HIDDEN
 713 bt_self_message_iterator_status ctf_fs_ds_file_next(
 714                 struct ctf_fs_ds_file *ds_file,
 715                 bt_message **msg)
 716 {
 717         enum bt_msg_iter_status msg_iter_status;
 718         bt_self_message_iterator_status status;
 719
 720         msg_iter_status = bt_msg_iter_get_next_message(
 721                 ds_file->msg_iter, ds_file->pc_msg_iter, msg);
 722
 723         switch (msg_iter_status) {
 724         case BT_MSG_ITER_STATUS_EOF:
 725                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_END;
 726                 break;
 727         case BT_MSG_ITER_STATUS_OK:
 728                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_OK;
 729                 break;
 730         case BT_MSG_ITER_STATUS_AGAIN:
 731                 /*
 732                  * Should not make it this far as this is
 733                  * medium-specific; there is nothing for the user to do
 734                  * and it should have been handled upstream.
 735                  */
 736                 abort();
 737         case BT_MSG_ITER_STATUS_INVAL:
 738         case BT_MSG_ITER_STATUS_ERROR:
 739         default:
 740                 status = BT_SELF_MESSAGE_ITERATOR_STATUS_ERROR;
 741                 break;
 742         }
 743         return status;
 744 }
 745
 746 BT_HIDDEN
 747 void ctf_fs_ds_index_destroy(struct ctf_fs_ds_index *index)
 748 {
 749         if (!index) {
 750                 return;
 751         }
 752
 753         if (index->entries) {
 754                 g_ptr_array_free(index->entries, TRUE);
 755         }
 756         g_free(index);
 757 }