src/plugins/ctf/common/bfcr/bfcr.c

   1 /*
   2  * Babeltrace - CTF binary field class reader (BFCR)
   3  *
   4  * Copyright (c) 2015-2016 EfficiOS Inc. and Linux Foundation
   5  * Copyright (c) 2015-2016 Philippe Proulx <pproulx@efficios.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE.
  24  */
  25
  26 #define BT_COMP_LOG_SELF_COMP (bfcr->self_comp)
  27 #define BT_LOG_OUTPUT_LEVEL (bfcr->log_level)
  28 #define BT_LOG_TAG "PLUGIN/CTF/BFCR"
  29 #include "plugins/comp-logging.h"
  30
  31 #include <stdlib.h>
  32 #include <stdint.h>
  33 #include <inttypes.h>
  34 #include <stdio.h>
  35 #include <stddef.h>
  36 #include <stdbool.h>
  37 #include "common/assert.h"
  38 #include <string.h>
  39 #include "compat/bitfield.h"
  40 #include "common/common.h"
  41 #include <babeltrace2/babeltrace.h>
  42 #include "common/align.h"
  43 #include <glib.h>
  44
  45 #include "bfcr.h"
  46 #include "../metadata/ctf-meta.h"
  47
  48 #define DIV8(_x)                        ((_x) >> 3)
  49 #define BYTES_TO_BITS(_x)               ((_x) * 8)
  50 #define BITS_TO_BYTES_FLOOR(_x)         DIV8(_x)
  51 #define BITS_TO_BYTES_CEIL(_x)          DIV8((_x) + 7)
  52 #define IN_BYTE_OFFSET(_at)             ((_at) & 7)
  53
  54 /* A visit stack entry */
  55 struct stack_entry {
  56         /*
  57          * Current class of base field, one of:
  58          *
  59          *   * Structure
  60          *   * Array
  61          *   * Sequence
  62          *   * Variant
  63          */
  64         struct ctf_field_class *base_class;
  65
  66         /* Length of base field (always 1 for a variant class) */
  67         int64_t base_len;
  68
  69         /* Index of next field to read */
  70         int64_t index;
  71 };
  72
  73 struct bt_bfcr;
  74
  75 /* Visit stack */
  76 struct stack {
  77         struct bt_bfcr *bfcr;
  78
  79         /* Entries (struct stack_entry) */
  80         GArray *entries;
  81
  82         /* Number of active entries */
  83         size_t size;
  84 };
  85
  86 /* Reading states */
  87 enum bfcr_state {
  88         BFCR_STATE_NEXT_FIELD,
  89         BFCR_STATE_ALIGN_BASIC,
  90         BFCR_STATE_ALIGN_COMPOUND,
  91         BFCR_STATE_READ_BASIC_BEGIN,
  92         BFCR_STATE_READ_BASIC_CONTINUE,
  93         BFCR_STATE_DONE,
  94 };
  95
  96 /* Binary class reader */
  97 struct bt_bfcr {
  98         bt_logging_level log_level;
  99
 100         /* Weak */
 101         bt_self_component *self_comp;
 102
 103         /* BFCR stack */
 104         struct stack *stack;
 105
 106         /* Current basic field class */
 107         struct ctf_field_class *cur_basic_field_class;
 108
 109         /* Current state */
 110         enum bfcr_state state;
 111
 112         /*
 113          * Last basic field class's byte order.
 114          *
 115          * This is used to detect errors since two contiguous basic
 116          * classes for which the common boundary is not the boundary of
 117          * a byte cannot have different byte orders.
 118          *
 119          * This is set to -1 on reset and when the last basic field class
 120          * was a string class.
 121          */
 122         enum ctf_byte_order last_bo;
 123
 124         /* Current byte order (copied to last_bo after a successful read) */
 125         enum ctf_byte_order cur_bo;
 126
 127         /* Stitch buffer infos */
 128         struct {
 129                 /* Stitch buffer */
 130                 uint8_t buf[16];
 131
 132                 /* Offset, within stitch buffer, of first bit */
 133                 size_t offset;
 134
 135                 /* Length (bits) of data in stitch buffer from offset */
 136                 size_t at;
 137         } stitch;
 138
 139         /* User buffer infos */
 140         struct {
 141                 /* Address */
 142                 const uint8_t *addr;
 143
 144                 /* Offset of data from address (bits) */
 145                 size_t offset;
 146
 147                 /* Current position from offset (bits) */
 148                 size_t at;
 149
 150                 /* Offset of offset within whole packet (bits) */
 151                 size_t packet_offset;
 152
 153                 /* Data size in buffer (bits) */
 154                 size_t sz;
 155
 156                 /* Buffer size (bytes) */
 157                 size_t buf_sz;
 158         } buf;
 159
 160         /* User stuff */
 161         struct {
 162                 /* Callback functions */
 163                 struct bt_bfcr_cbs cbs;
 164
 165                 /* Private data */
 166                 void *data;
 167         } user;
 168 };
 169
 170 static inline
 171 const char *bfcr_state_string(enum bfcr_state state)
 172 {
 173         switch (state) {
 174         case BFCR_STATE_NEXT_FIELD:
 175                 return "BFCR_STATE_NEXT_FIELD";
 176         case BFCR_STATE_ALIGN_BASIC:
 177                 return "BFCR_STATE_ALIGN_BASIC";
 178         case BFCR_STATE_ALIGN_COMPOUND:
 179                 return "BFCR_STATE_ALIGN_COMPOUND";
 180         case BFCR_STATE_READ_BASIC_BEGIN:
 181                 return "BFCR_STATE_READ_BASIC_BEGIN";
 182         case BFCR_STATE_READ_BASIC_CONTINUE:
 183                 return "BFCR_STATE_READ_BASIC_CONTINUE";
 184         case BFCR_STATE_DONE:
 185                 return "BFCR_STATE_DONE";
 186         default:
 187                 return "(unknown)";
 188         }
 189 }
 190
 191 static
 192 struct stack *stack_new(struct bt_bfcr *bfcr)
 193 {
 194         struct stack *stack = NULL;
 195
 196         stack = g_new0(struct stack, 1);
 197         if (!stack) {
 198                 BT_COMP_LOGE_STR("Failed to allocate one stack.");
 199                 goto error;
 200         }
 201
 202         stack->bfcr = bfcr;
 203         stack->entries = g_array_new(FALSE, TRUE, sizeof(struct stack_entry));
 204         if (!stack->entries) {
 205                 BT_COMP_LOGE_STR("Failed to allocate a GArray.");
 206                 goto error;
 207         }
 208
 209         BT_COMP_LOGD("Created stack: addr=%p", stack);
 210         return stack;
 211
 212 error:
 213         g_free(stack);
 214         return NULL;
 215 }
 216
 217 static
 218 void stack_destroy(struct stack *stack)
 219 {
 220         struct bt_bfcr *bfcr;
 221
 222         if (!stack) {
 223                 return;
 224         }
 225
 226         bfcr = stack->bfcr;
 227         BT_COMP_LOGD("Destroying stack: addr=%p", stack);
 228
 229         if (stack->entries) {
 230                 g_array_free(stack->entries, TRUE);
 231         }
 232
 233         g_free(stack);
 234 }
 235
 236 static
 237 int stack_push(struct stack *stack, struct ctf_field_class *base_class,
 238         size_t base_len)
 239 {
 240         struct stack_entry *entry;
 241         struct bt_bfcr *bfcr;
 242
 243         BT_ASSERT(stack);
 244         BT_ASSERT(base_class);
 245         bfcr = stack->bfcr;
 246         BT_COMP_LOGT("Pushing field class on stack: stack-addr=%p, "
 247                 "fc-addr=%p, fc-type=%d, base-length=%zu, "
 248                 "stack-size-before=%zu, stack-size-after=%zu",
 249                 stack, base_class, base_class->type,
 250                 base_len, stack->size, stack->size + 1);
 251
 252         if (stack->entries->len == stack->size) {
 253                 g_array_set_size(stack->entries, stack->size + 1);
 254         }
 255
 256         entry = &g_array_index(stack->entries, struct stack_entry, stack->size);
 257         entry->base_class = base_class;
 258         entry->base_len = base_len;
 259         entry->index = 0;
 260         stack->size++;
 261         return 0;
 262 }
 263
 264 static inline
 265 int64_t get_compound_field_class_length(struct bt_bfcr *bfcr,
 266                 struct ctf_field_class *fc)
 267 {
 268         int64_t length;
 269
 270         switch (fc->type) {
 271         case CTF_FIELD_CLASS_TYPE_STRUCT:
 272         {
 273                 struct ctf_field_class_struct *struct_fc = (void *) fc;
 274
 275                 length = (int64_t) struct_fc->members->len;
 276                 break;
 277         }
 278         case CTF_FIELD_CLASS_TYPE_VARIANT:
 279         {
 280                 /* Variant field classes always "contain" a single class */
 281                 length = 1;
 282                 break;
 283         }
 284         case CTF_FIELD_CLASS_TYPE_ARRAY:
 285         {
 286                 struct ctf_field_class_array *array_fc = (void *) fc;
 287
 288                 length = (int64_t) array_fc->length;
 289                 break;
 290         }
 291         case CTF_FIELD_CLASS_TYPE_SEQUENCE:
 292                 length = bfcr->user.cbs.query.get_sequence_length(fc,
 293                         bfcr->user.data);
 294                 break;
 295         default:
 296                 abort();
 297         }
 298
 299         return length;
 300 }
 301
 302 static
 303 int stack_push_with_len(struct bt_bfcr *bfcr, struct ctf_field_class *base_class)
 304 {
 305         int ret;
 306         int64_t length = get_compound_field_class_length(bfcr, base_class);
 307
 308         if (length < 0) {
 309                 BT_COMP_LOGW("Cannot get compound field class's field count: "
 310                         "bfcr-addr=%p, fc-addr=%p, fc-type=%d",
 311                         bfcr, base_class, base_class->type);
 312                 ret = BT_BFCR_STATUS_ERROR;
 313                 goto end;
 314         }
 315
 316         ret = stack_push(bfcr->stack, base_class, (size_t) length);
 317
 318 end:
 319         return ret;
 320 }
 321
 322 static inline
 323 unsigned int stack_size(struct stack *stack)
 324 {
 325         BT_ASSERT(stack);
 326         return stack->size;
 327 }
 328
 329 static
 330 void stack_pop(struct stack *stack)
 331 {
 332         struct bt_bfcr *bfcr;
 333
 334         BT_ASSERT(stack);
 335         BT_ASSERT(stack_size(stack));
 336         bfcr = stack->bfcr;
 337         BT_COMP_LOGT("Popping from stack: "
 338                 "stack-addr=%p, stack-size-before=%u, stack-size-after=%u",
 339                 stack, stack->entries->len, stack->entries->len - 1);
 340         stack->size--;
 341 }
 342
 343 static inline
 344 bool stack_empty(struct stack *stack)
 345 {
 346         return stack_size(stack) == 0;
 347 }
 348
 349 static
 350 void stack_clear(struct stack *stack)
 351 {
 352         BT_ASSERT(stack);
 353         stack->size = 0;
 354 }
 355
 356 static inline
 357 struct stack_entry *stack_top(struct stack *stack)
 358 {
 359         BT_ASSERT(stack);
 360         BT_ASSERT(stack_size(stack));
 361         return &g_array_index(stack->entries, struct stack_entry,
 362                 stack->size - 1);
 363 }
 364
 365 static inline
 366 size_t available_bits(struct bt_bfcr *bfcr)
 367 {
 368         return bfcr->buf.sz - bfcr->buf.at;
 369 }
 370
 371 static inline
 372 void consume_bits(struct bt_bfcr *bfcr, size_t incr)
 373 {
 374         BT_COMP_LOGT("Advancing cursor: bfcr-addr=%p, cur-before=%zu, cur-after=%zu",
 375                 bfcr, bfcr->buf.at, bfcr->buf.at + incr);
 376         bfcr->buf.at += incr;
 377 }
 378
 379 static inline
 380 bool has_enough_bits(struct bt_bfcr *bfcr, size_t sz)
 381 {
 382         return available_bits(bfcr) >= sz;
 383 }
 384
 385 static inline
 386 bool at_least_one_bit_left(struct bt_bfcr *bfcr)
 387 {
 388         return has_enough_bits(bfcr, 1);
 389 }
 390
 391 static inline
 392 size_t packet_at(struct bt_bfcr *bfcr)
 393 {
 394         return bfcr->buf.packet_offset + bfcr->buf.at;
 395 }
 396
 397 static inline
 398 size_t buf_at_from_addr(struct bt_bfcr *bfcr)
 399 {
 400         /*
 401          * Considering this:
 402          *
 403          *     ====== offset ===== (17)
 404          *
 405          *     xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx
 406          *     ^
 407          *     addr (0)           ==== at ==== (12)
 408          *
 409          * We want this:
 410          *
 411          *     =============================== (29)
 412          */
 413         return bfcr->buf.offset + bfcr->buf.at;
 414 }
 415
 416 static
 417 void stitch_reset(struct bt_bfcr *bfcr)
 418 {
 419         bfcr->stitch.offset = 0;
 420         bfcr->stitch.at = 0;
 421 }
 422
 423 static inline
 424 size_t stitch_at_from_addr(struct bt_bfcr *bfcr)
 425 {
 426         return bfcr->stitch.offset + bfcr->stitch.at;
 427 }
 428
 429 static
 430 void stitch_append_from_buf(struct bt_bfcr *bfcr, size_t sz)
 431 {
 432         size_t stitch_byte_at;
 433         size_t buf_byte_at;
 434         size_t nb_bytes;
 435
 436         if (sz == 0) {
 437                 return;
 438         }
 439
 440         stitch_byte_at =
 441                 BITS_TO_BYTES_FLOOR(stitch_at_from_addr(bfcr));
 442         buf_byte_at = BITS_TO_BYTES_FLOOR(buf_at_from_addr(bfcr));
 443         nb_bytes = BITS_TO_BYTES_CEIL(sz);
 444         BT_ASSERT(nb_bytes > 0);
 445         BT_ASSERT(bfcr->buf.addr);
 446         memcpy(&bfcr->stitch.buf[stitch_byte_at], &bfcr->buf.addr[buf_byte_at],
 447                 nb_bytes);
 448         bfcr->stitch.at += sz;
 449         consume_bits(bfcr, sz);
 450 }
 451
 452 static
 453 void stitch_append_from_remaining_buf(struct bt_bfcr *bfcr)
 454 {
 455         stitch_append_from_buf(bfcr, available_bits(bfcr));
 456 }
 457
 458 static
 459 void stitch_set_from_remaining_buf(struct bt_bfcr *bfcr)
 460 {
 461         stitch_reset(bfcr);
 462         bfcr->stitch.offset = IN_BYTE_OFFSET(buf_at_from_addr(bfcr));
 463         stitch_append_from_remaining_buf(bfcr);
 464 }
 465
 466 static inline
 467 void read_unsigned_bitfield(struct bt_bfcr *bfcr, const uint8_t *buf, size_t at,
 468                 unsigned int field_size, enum ctf_byte_order bo,
 469                 uint64_t *v)
 470 {
 471         switch (bo) {
 472         case CTF_BYTE_ORDER_BIG:
 473                 bt_bitfield_read_be(buf, uint8_t, at, field_size, v);
 474                 break;
 475         case CTF_BYTE_ORDER_LITTLE:
 476                 bt_bitfield_read_le(buf, uint8_t, at, field_size, v);
 477                 break;
 478         default:
 479                 abort();
 480         }
 481
 482         BT_COMP_LOGT("Read unsigned bit array: cur=%zu, size=%u, "
 483                 "bo=%d, val=%" PRIu64, at, field_size, bo, *v);
 484 }
 485
 486 static inline
 487 void read_signed_bitfield(struct bt_bfcr *bfcr, const uint8_t *buf, size_t at,
 488                 unsigned int field_size, enum ctf_byte_order bo, int64_t *v)
 489 {
 490         switch (bo) {
 491         case CTF_BYTE_ORDER_BIG:
 492                 bt_bitfield_read_be(buf, uint8_t, at, field_size, v);
 493                 break;
 494         case CTF_BYTE_ORDER_LITTLE:
 495                 bt_bitfield_read_le(buf, uint8_t, at, field_size, v);
 496                 break;
 497         default:
 498                 abort();
 499         }
 500
 501         BT_COMP_LOGT("Read signed bit array: cur=%zu, size=%u, "
 502                 "bo=%d, val=%" PRId64, at, field_size, bo, *v);
 503 }
 504
 505 typedef enum bt_bfcr_status (* read_basic_and_call_cb_t)(struct bt_bfcr *,
 506                 const uint8_t *, size_t);
 507
 508 static inline
 509 enum bt_bfcr_status validate_contiguous_bo(struct bt_bfcr *bfcr,
 510                 enum ctf_byte_order next_bo)
 511 {
 512         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 513
 514         /* Always valid when at a byte boundary */
 515         if (packet_at(bfcr) % 8 == 0) {
 516                 goto end;
 517         }
 518
 519         /* Always valid if last byte order is unknown */
 520         if (bfcr->last_bo == -1) {
 521                 goto end;
 522         }
 523
 524         /* Always valid if next byte order is unknown */
 525         if (next_bo == -1) {
 526                 goto end;
 527         }
 528
 529         /* Make sure last byte order is compatible with the next byte order */
 530         switch (bfcr->last_bo) {
 531         case CTF_BYTE_ORDER_BIG:
 532                 if (next_bo != CTF_BYTE_ORDER_BIG) {
 533                         status = BT_BFCR_STATUS_ERROR;
 534                 }
 535                 break;
 536         case CTF_BYTE_ORDER_LITTLE:
 537                 if (next_bo != CTF_BYTE_ORDER_LITTLE) {
 538                         status = BT_BFCR_STATUS_ERROR;
 539                 }
 540                 break;
 541         default:
 542                 status = BT_BFCR_STATUS_ERROR;
 543         }
 544
 545 end:
 546         if (status < 0) {
 547                 BT_COMP_LOGW("Cannot read bit array: two different byte orders not at a byte boundary: "
 548                         "bfcr-addr=%p, last-bo=%d, next-bo=%d",
 549                         bfcr, bfcr->last_bo, next_bo);
 550         }
 551
 552         return status;
 553 }
 554
 555 static
 556 enum bt_bfcr_status read_basic_float_and_call_cb(struct bt_bfcr *bfcr,
 557                 const uint8_t *buf, size_t at)
 558 {
 559         double dblval;
 560         unsigned int field_size;
 561         enum ctf_byte_order bo;
 562         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 563         struct ctf_field_class_float *fc = (void *) bfcr->cur_basic_field_class;
 564
 565         BT_ASSERT(fc);
 566         field_size = fc->base.size;
 567         bo = fc->base.byte_order;
 568         bfcr->cur_bo = bo;
 569
 570         switch (field_size) {
 571         case 32:
 572         {
 573                 uint64_t v;
 574                 union {
 575                         uint32_t u;
 576                         float f;
 577                 } f32;
 578
 579                 read_unsigned_bitfield(bfcr, buf, at, field_size, bo, &v);
 580                 f32.u = (uint32_t) v;
 581                 dblval = (double) f32.f;
 582                 break;
 583         }
 584         case 64:
 585         {
 586                 union {
 587                         uint64_t u;
 588                         double d;
 589                 } f64;
 590
 591                 read_unsigned_bitfield(bfcr, buf, at, field_size, bo, &f64.u);
 592                 dblval = f64.d;
 593                 break;
 594         }
 595         default:
 596                 /* Only 32-bit and 64-bit fields are supported currently */
 597                 abort();
 598         }
 599
 600         BT_COMP_LOGT("Read floating point number value: bfcr=%p, cur=%zu, val=%f",
 601                 bfcr, at, dblval);
 602
 603         if (bfcr->user.cbs.classes.floating_point) {
 604                 BT_COMP_LOGT("Calling user function (floating point number).");
 605                 status = bfcr->user.cbs.classes.floating_point(dblval,
 606                         bfcr->cur_basic_field_class, bfcr->user.data);
 607                 BT_COMP_LOGT("User function returned: status=%s",
 608                         bt_bfcr_status_string(status));
 609                 if (status != BT_BFCR_STATUS_OK) {
 610                         BT_COMP_LOGW("User function failed: bfcr-addr=%p, status=%s",
 611                                 bfcr, bt_bfcr_status_string(status));
 612                 }
 613         }
 614
 615         return status;
 616 }
 617
 618 static inline
 619 enum bt_bfcr_status read_basic_int_and_call_cb(struct bt_bfcr *bfcr,
 620                 const uint8_t *buf, size_t at)
 621 {
 622         unsigned int field_size;
 623         enum ctf_byte_order bo;
 624         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 625         struct ctf_field_class_int *fc = (void *) bfcr->cur_basic_field_class;
 626
 627         field_size = fc->base.size;
 628         bo = fc->base.byte_order;
 629
 630         /*
 631          * Update current byte order now because we could be reading
 632          * the integer value of an enumeration class, and thus we know
 633          * here the actual supporting integer class's byte order.
 634          */
 635         bfcr->cur_bo = bo;
 636
 637         if (fc->is_signed) {
 638                 int64_t v;
 639
 640                 read_signed_bitfield(bfcr, buf, at, field_size, bo, &v);
 641
 642                 if (bfcr->user.cbs.classes.signed_int) {
 643                         BT_COMP_LOGT("Calling user function (signed integer).");
 644                         status = bfcr->user.cbs.classes.signed_int(v,
 645                                 bfcr->cur_basic_field_class, bfcr->user.data);
 646                         BT_COMP_LOGT("User function returned: status=%s",
 647                                 bt_bfcr_status_string(status));
 648                         if (status != BT_BFCR_STATUS_OK) {
 649                                 BT_COMP_LOGW("User function failed: "
 650                                         "bfcr-addr=%p, status=%s",
 651                                         bfcr, bt_bfcr_status_string(status));
 652                         }
 653                 }
 654         } else {
 655                 uint64_t v;
 656
 657                 read_unsigned_bitfield(bfcr, buf, at, field_size, bo, &v);
 658
 659                 if (bfcr->user.cbs.classes.unsigned_int) {
 660                         BT_COMP_LOGT("Calling user function (unsigned integer).");
 661                         status = bfcr->user.cbs.classes.unsigned_int(v,
 662                                 bfcr->cur_basic_field_class, bfcr->user.data);
 663                         BT_COMP_LOGT("User function returned: status=%s",
 664                                 bt_bfcr_status_string(status));
 665                         if (status != BT_BFCR_STATUS_OK) {
 666                                 BT_COMP_LOGW("User function failed: "
 667                                         "bfcr-addr=%p, status=%s",
 668                                         bfcr, bt_bfcr_status_string(status));
 669                         }
 670                 }
 671         }
 672
 673         return status;
 674 }
 675
 676 static inline
 677 enum bt_bfcr_status read_bit_array_class_and_call_continue(struct bt_bfcr *bfcr,
 678                 read_basic_and_call_cb_t read_basic_and_call_cb)
 679 {
 680         size_t available;
 681         size_t needed_bits;
 682         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 683         struct ctf_field_class_bit_array *fc =
 684                 (void *) bfcr->cur_basic_field_class;
 685
 686         if (!at_least_one_bit_left(bfcr)) {
 687                 BT_COMP_LOGT("Reached end of data: bfcr-addr=%p", bfcr);
 688                 status = BT_BFCR_STATUS_EOF;
 689                 goto end;
 690         }
 691
 692         available = available_bits(bfcr);
 693         needed_bits = fc->size - bfcr->stitch.at;
 694         BT_COMP_LOGT("Continuing basic field decoding: "
 695                 "bfcr-addr=%p, field-size=%u, needed-size=%zu, "
 696                 "available-size=%zu",
 697                 bfcr, fc->size, needed_bits, available);
 698         if (needed_bits <= available) {
 699                 /* We have all the bits; append to stitch, then decode */
 700                 stitch_append_from_buf(bfcr, needed_bits);
 701                 status = read_basic_and_call_cb(bfcr, bfcr->stitch.buf,
 702                         bfcr->stitch.offset);
 703                 if (status != BT_BFCR_STATUS_OK) {
 704                         BT_COMP_LOGW("Cannot read basic field: "
 705                                 "bfcr-addr=%p, fc-addr=%p, status=%s",
 706                                 bfcr, bfcr->cur_basic_field_class,
 707                                 bt_bfcr_status_string(status));
 708                         goto end;
 709                 }
 710
 711                 if (stack_empty(bfcr->stack)) {
 712                         /* Root is a basic class */
 713                         bfcr->state = BFCR_STATE_DONE;
 714                 } else {
 715                         /* Go to next field */
 716                         stack_top(bfcr->stack)->index++;
 717                         bfcr->state = BFCR_STATE_NEXT_FIELD;
 718                         bfcr->last_bo = bfcr->cur_bo;
 719                 }
 720                 goto end;
 721         }
 722
 723         /* We are here; it means we don't have enough data to decode this */
 724         BT_COMP_LOGT_STR("Not enough data to read the next basic field: appending to stitch buffer.");
 725         stitch_append_from_remaining_buf(bfcr);
 726         status = BT_BFCR_STATUS_EOF;
 727
 728 end:
 729         return status;
 730 }
 731
 732 static inline
 733 enum bt_bfcr_status read_bit_array_class_and_call_begin(struct bt_bfcr *bfcr,
 734                 read_basic_and_call_cb_t read_basic_and_call_cb)
 735 {
 736         size_t available;
 737         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 738         struct ctf_field_class_bit_array *fc =
 739                 (void *) bfcr->cur_basic_field_class;
 740
 741         if (!at_least_one_bit_left(bfcr)) {
 742                 BT_COMP_LOGT("Reached end of data: bfcr-addr=%p", bfcr);
 743                 status = BT_BFCR_STATUS_EOF;
 744                 goto end;
 745         }
 746
 747         status = validate_contiguous_bo(bfcr, fc->byte_order);
 748         if (status != BT_BFCR_STATUS_OK) {
 749                 /* validate_contiguous_bo() logs errors */
 750                 goto end;
 751         }
 752
 753         available = available_bits(bfcr);
 754
 755         if (fc->size <= available) {
 756                 /* We have all the bits; decode and set now */
 757                 BT_ASSERT(bfcr->buf.addr);
 758                 status = read_basic_and_call_cb(bfcr, bfcr->buf.addr,
 759                         buf_at_from_addr(bfcr));
 760                 if (status != BT_BFCR_STATUS_OK) {
 761                         BT_COMP_LOGW("Cannot read basic field: "
 762                                 "bfcr-addr=%p, fc-addr=%p, status=%s",
 763                                 bfcr, bfcr->cur_basic_field_class,
 764                                 bt_bfcr_status_string(status));
 765                         goto end;
 766                 }
 767
 768                 consume_bits(bfcr, fc->size);
 769
 770                 if (stack_empty(bfcr->stack)) {
 771                         /* Root is a basic class */
 772                         bfcr->state = BFCR_STATE_DONE;
 773                 } else {
 774                         /* Go to next field */
 775                         stack_top(bfcr->stack)->index++;
 776                         bfcr->state = BFCR_STATE_NEXT_FIELD;
 777                         bfcr->last_bo = bfcr->cur_bo;
 778                 }
 779
 780                 goto end;
 781         }
 782
 783         /* We are here; it means we don't have enough data to decode this */
 784         BT_COMP_LOGT_STR("Not enough data to read the next basic field: setting stitch buffer.");
 785         stitch_set_from_remaining_buf(bfcr);
 786         bfcr->state = BFCR_STATE_READ_BASIC_CONTINUE;
 787         status = BT_BFCR_STATUS_EOF;
 788
 789 end:
 790         return status;
 791 }
 792
 793 static inline
 794 enum bt_bfcr_status read_basic_int_class_and_call_begin(
 795                 struct bt_bfcr *bfcr)
 796 {
 797         return read_bit_array_class_and_call_begin(bfcr, read_basic_int_and_call_cb);
 798 }
 799
 800 static inline
 801 enum bt_bfcr_status read_basic_int_class_and_call_continue(
 802                 struct bt_bfcr *bfcr)
 803 {
 804         return read_bit_array_class_and_call_continue(bfcr,
 805                 read_basic_int_and_call_cb);
 806 }
 807
 808 static inline
 809 enum bt_bfcr_status read_basic_float_class_and_call_begin(
 810                 struct bt_bfcr *bfcr)
 811 {
 812         return read_bit_array_class_and_call_begin(bfcr,
 813                 read_basic_float_and_call_cb);
 814 }
 815
 816 static inline
 817 enum bt_bfcr_status read_basic_float_class_and_call_continue(
 818                 struct bt_bfcr *bfcr)
 819 {
 820         return read_bit_array_class_and_call_continue(bfcr,
 821                 read_basic_float_and_call_cb);
 822 }
 823
 824 static inline
 825 enum bt_bfcr_status read_basic_string_class_and_call(
 826                 struct bt_bfcr *bfcr, bool begin)
 827 {
 828         size_t buf_at_bytes;
 829         const uint8_t *result;
 830         size_t available_bytes;
 831         const uint8_t *first_chr;
 832         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 833
 834         if (!at_least_one_bit_left(bfcr)) {
 835                 BT_COMP_LOGT("Reached end of data: bfcr-addr=%p", bfcr);
 836                 status = BT_BFCR_STATUS_EOF;
 837                 goto end;
 838         }
 839
 840         BT_ASSERT(buf_at_from_addr(bfcr) % 8 == 0);
 841         available_bytes = BITS_TO_BYTES_FLOOR(available_bits(bfcr));
 842         buf_at_bytes = BITS_TO_BYTES_FLOOR(buf_at_from_addr(bfcr));
 843         BT_ASSERT(bfcr->buf.addr);
 844         first_chr = &bfcr->buf.addr[buf_at_bytes];
 845         result = memchr(first_chr, '\0', available_bytes);
 846
 847         if (begin && bfcr->user.cbs.classes.string_begin) {
 848                 BT_COMP_LOGT("Calling user function (string, beginning).");
 849                 status = bfcr->user.cbs.classes.string_begin(
 850                         bfcr->cur_basic_field_class, bfcr->user.data);
 851                 BT_COMP_LOGT("User function returned: status=%s",
 852                         bt_bfcr_status_string(status));
 853                 if (status != BT_BFCR_STATUS_OK) {
 854                         BT_COMP_LOGW("User function failed: bfcr-addr=%p, status=%s",
 855                                 bfcr, bt_bfcr_status_string(status));
 856                         goto end;
 857                 }
 858         }
 859
 860         if (!result) {
 861                 /* No null character yet */
 862                 if (bfcr->user.cbs.classes.string) {
 863                         BT_COMP_LOGT("Calling user function (substring).");
 864                         status = bfcr->user.cbs.classes.string(
 865                                 (const char *) first_chr,
 866                                 available_bytes, bfcr->cur_basic_field_class,
 867                                 bfcr->user.data);
 868                         BT_COMP_LOGT("User function returned: status=%s",
 869                                 bt_bfcr_status_string(status));
 870                         if (status != BT_BFCR_STATUS_OK) {
 871                                 BT_COMP_LOGW("User function failed: "
 872                                         "bfcr-addr=%p, status=%s",
 873                                         bfcr, bt_bfcr_status_string(status));
 874                                 goto end;
 875                         }
 876                 }
 877
 878                 consume_bits(bfcr, BYTES_TO_BITS(available_bytes));
 879                 bfcr->state = BFCR_STATE_READ_BASIC_CONTINUE;
 880                 status = BT_BFCR_STATUS_EOF;
 881         } else {
 882                 /* Found the null character */
 883                 size_t result_len = (size_t) (result - first_chr);
 884
 885                 if (bfcr->user.cbs.classes.string && result_len) {
 886                         BT_COMP_LOGT("Calling user function (substring).");
 887                         status = bfcr->user.cbs.classes.string(
 888                                 (const char *) first_chr,
 889                                 result_len, bfcr->cur_basic_field_class,
 890                                 bfcr->user.data);
 891                         BT_COMP_LOGT("User function returned: status=%s",
 892                                 bt_bfcr_status_string(status));
 893                         if (status != BT_BFCR_STATUS_OK) {
 894                                 BT_COMP_LOGW("User function failed: "
 895                                         "bfcr-addr=%p, status=%s",
 896                                         bfcr, bt_bfcr_status_string(status));
 897                                 goto end;
 898                         }
 899                 }
 900
 901                 if (bfcr->user.cbs.classes.string_end) {
 902                         BT_COMP_LOGT("Calling user function (string, end).");
 903                         status = bfcr->user.cbs.classes.string_end(
 904                                 bfcr->cur_basic_field_class, bfcr->user.data);
 905                         BT_COMP_LOGT("User function returned: status=%s",
 906                                 bt_bfcr_status_string(status));
 907                         if (status != BT_BFCR_STATUS_OK) {
 908                                 BT_COMP_LOGW("User function failed: "
 909                                         "bfcr-addr=%p, status=%s",
 910                                         bfcr, bt_bfcr_status_string(status));
 911                                 goto end;
 912                         }
 913                 }
 914
 915                 consume_bits(bfcr, BYTES_TO_BITS(result_len + 1));
 916
 917                 if (stack_empty(bfcr->stack)) {
 918                         /* Root is a basic class */
 919                         bfcr->state = BFCR_STATE_DONE;
 920                 } else {
 921                         /* Go to next field */
 922                         stack_top(bfcr->stack)->index++;
 923                         bfcr->state = BFCR_STATE_NEXT_FIELD;
 924                         bfcr->last_bo = bfcr->cur_bo;
 925                 }
 926         }
 927
 928 end:
 929         return status;
 930 }
 931
 932 static inline
 933 enum bt_bfcr_status read_basic_begin_state(struct bt_bfcr *bfcr)
 934 {
 935         enum bt_bfcr_status status;
 936
 937         BT_ASSERT(bfcr->cur_basic_field_class);
 938
 939         switch (bfcr->cur_basic_field_class->type) {
 940         case CTF_FIELD_CLASS_TYPE_INT:
 941         case CTF_FIELD_CLASS_TYPE_ENUM:
 942                 status = read_basic_int_class_and_call_begin(bfcr);
 943                 break;
 944         case CTF_FIELD_CLASS_TYPE_FLOAT:
 945                 status = read_basic_float_class_and_call_begin(bfcr);
 946                 break;
 947         case CTF_FIELD_CLASS_TYPE_STRING:
 948                 status = read_basic_string_class_and_call(bfcr, true);
 949                 break;
 950         default:
 951                 abort();
 952         }
 953
 954         return status;
 955 }
 956
 957 static inline
 958 enum bt_bfcr_status read_basic_continue_state(struct bt_bfcr *bfcr)
 959 {
 960         enum bt_bfcr_status status;
 961
 962         BT_ASSERT(bfcr->cur_basic_field_class);
 963
 964         switch (bfcr->cur_basic_field_class->type) {
 965         case CTF_FIELD_CLASS_TYPE_INT:
 966         case CTF_FIELD_CLASS_TYPE_ENUM:
 967                 status = read_basic_int_class_and_call_continue(bfcr);
 968                 break;
 969         case CTF_FIELD_CLASS_TYPE_FLOAT:
 970                 status = read_basic_float_class_and_call_continue(bfcr);
 971                 break;
 972         case CTF_FIELD_CLASS_TYPE_STRING:
 973                 status = read_basic_string_class_and_call(bfcr, false);
 974                 break;
 975         default:
 976                 abort();
 977         }
 978
 979         return status;
 980 }
 981
 982 static inline
 983 size_t bits_to_skip_to_align_to(struct bt_bfcr *bfcr, size_t align)
 984 {
 985         size_t aligned_packet_at;
 986
 987         aligned_packet_at = ALIGN(packet_at(bfcr), align);
 988         return aligned_packet_at - packet_at(bfcr);
 989 }
 990
 991 static inline
 992 enum bt_bfcr_status align_class_state(struct bt_bfcr *bfcr,
 993                 struct ctf_field_class *field_class, enum bfcr_state next_state)
 994 {
 995         unsigned int field_alignment;
 996         size_t skip_bits;
 997         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
 998
 999         /* Get field's alignment */
1000         field_alignment = field_class->alignment;
1001
1002         /*
1003          * 0 means "undefined" for variants; what we really want is 1
1004          * (always aligned)
1005          */
1006         BT_ASSERT(field_alignment >= 1);
1007
1008         /* Compute how many bits we need to skip */
1009         skip_bits = bits_to_skip_to_align_to(bfcr, (size_t) field_alignment);
1010
1011         /* Nothing to skip? aligned */
1012         if (skip_bits == 0) {
1013                 bfcr->state = next_state;
1014                 goto end;
1015         }
1016
1017         /* Make sure there's at least one bit left */
1018         if (!at_least_one_bit_left(bfcr)) {
1019                 status = BT_BFCR_STATUS_EOF;
1020                 goto end;
1021         }
1022
1023         /* Consume as many bits as possible in what's left */
1024         consume_bits(bfcr, MIN(available_bits(bfcr), skip_bits));
1025
1026         /* Are we done now? */
1027         skip_bits = bits_to_skip_to_align_to(bfcr, field_alignment);
1028         if (skip_bits == 0) {
1029                 /* Yes: go to next state */
1030                 bfcr->state = next_state;
1031                 goto end;
1032         } else {
1033                 /* No: need more data */
1034                 BT_COMP_LOGT("Reached end of data when aligning: bfcr-addr=%p", bfcr);
1035                 status = BT_BFCR_STATUS_EOF;
1036         }
1037
1038 end:
1039         return status;
1040 }
1041
1042 static inline
1043 enum bt_bfcr_status next_field_state(struct bt_bfcr *bfcr)
1044 {
1045         int ret;
1046         struct stack_entry *top;
1047         struct ctf_field_class *next_field_class = NULL;
1048         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
1049
1050         if (stack_empty(bfcr->stack)) {
1051                 goto end;
1052         }
1053
1054         top = stack_top(bfcr->stack);
1055
1056         /* Are we done with this base class? */
1057         while (top->index == top->base_len) {
1058                 if (bfcr->user.cbs.classes.compound_end) {
1059                         BT_COMP_LOGT("Calling user function (compound, end).");
1060                         status = bfcr->user.cbs.classes.compound_end(
1061                                 top->base_class, bfcr->user.data);
1062                         BT_COMP_LOGT("User function returned: status=%s",
1063                                 bt_bfcr_status_string(status));
1064                         if (status != BT_BFCR_STATUS_OK) {
1065                                 BT_COMP_LOGW("User function failed: bfcr-addr=%p, status=%s",
1066                                         bfcr, bt_bfcr_status_string(status));
1067                                 goto end;
1068                         }
1069                 }
1070
1071                 stack_pop(bfcr->stack);
1072
1073                 /* Are we done with the root class? */
1074                 if (stack_empty(bfcr->stack)) {
1075                         bfcr->state = BFCR_STATE_DONE;
1076                         goto end;
1077                 }
1078
1079                 top = stack_top(bfcr->stack);
1080                 top->index++;
1081         }
1082
1083         /* Get next field's class */
1084         switch (top->base_class->type) {
1085         case CTF_FIELD_CLASS_TYPE_STRUCT:
1086                 next_field_class = ctf_field_class_struct_borrow_member_by_index(
1087                         (void *) top->base_class, (uint64_t) top->index)->fc;
1088                 break;
1089         case CTF_FIELD_CLASS_TYPE_ARRAY:
1090         case CTF_FIELD_CLASS_TYPE_SEQUENCE:
1091         {
1092                 struct ctf_field_class_array_base *array_fc =
1093                         (void *) top->base_class;
1094
1095                 next_field_class = array_fc->elem_fc;
1096                 break;
1097         }
1098         case CTF_FIELD_CLASS_TYPE_VARIANT:
1099                 /* Variant classes are dynamic: the user should know! */
1100                 next_field_class =
1101                         bfcr->user.cbs.query.borrow_variant_selected_field_class(
1102                                 top->base_class, bfcr->user.data);
1103                 break;
1104         default:
1105                 break;
1106         }
1107
1108         if (!next_field_class) {
1109                 BT_COMP_LOGW("Cannot get the field class of the next field: "
1110                         "bfcr-addr=%p, base-fc-addr=%p, base-fc-type=%d, "
1111                         "index=%" PRId64,
1112                         bfcr, top->base_class, top->base_class->type,
1113                         top->index);
1114                 status = BT_BFCR_STATUS_ERROR;
1115                 goto end;
1116         }
1117
1118         if (next_field_class->is_compound) {
1119                 if (bfcr->user.cbs.classes.compound_begin) {
1120                         BT_COMP_LOGT("Calling user function (compound, begin).");
1121                         status = bfcr->user.cbs.classes.compound_begin(
1122                                 next_field_class, bfcr->user.data);
1123                         BT_COMP_LOGT("User function returned: status=%s",
1124                                 bt_bfcr_status_string(status));
1125                         if (status != BT_BFCR_STATUS_OK) {
1126                                 BT_COMP_LOGW("User function failed: bfcr-addr=%p, status=%s",
1127                                         bfcr, bt_bfcr_status_string(status));
1128                                 goto end;
1129                         }
1130                 }
1131
1132                 ret = stack_push_with_len(bfcr, next_field_class);
1133                 if (ret) {
1134                         /* stack_push_with_len() logs errors */
1135                         status = BT_BFCR_STATUS_ERROR;
1136                         goto end;
1137                 }
1138
1139                 /* Next state: align a compound class */
1140                 bfcr->state = BFCR_STATE_ALIGN_COMPOUND;
1141         } else {
1142                 /* Replace current basic field class */
1143                 BT_COMP_LOGT("Replacing current basic field class: "
1144                         "bfcr-addr=%p, cur-basic-fc-addr=%p, "
1145                         "next-basic-fc-addr=%p",
1146                         bfcr, bfcr->cur_basic_field_class, next_field_class);
1147                 bfcr->cur_basic_field_class = next_field_class;
1148
1149                 /* Next state: align a basic class */
1150                 bfcr->state = BFCR_STATE_ALIGN_BASIC;
1151         }
1152
1153 end:
1154         return status;
1155 }
1156
1157 static inline
1158 enum bt_bfcr_status handle_state(struct bt_bfcr *bfcr)
1159 {
1160         enum bt_bfcr_status status = BT_BFCR_STATUS_OK;
1161
1162         BT_COMP_LOGT("Handling state: bfcr-addr=%p, state=%s",
1163                 bfcr, bfcr_state_string(bfcr->state));
1164
1165         switch (bfcr->state) {
1166         case BFCR_STATE_NEXT_FIELD:
1167                 status = next_field_state(bfcr);
1168                 break;
1169         case BFCR_STATE_ALIGN_BASIC:
1170                 status = align_class_state(bfcr, bfcr->cur_basic_field_class,
1171                         BFCR_STATE_READ_BASIC_BEGIN);
1172                 break;
1173         case BFCR_STATE_ALIGN_COMPOUND:
1174                 status = align_class_state(bfcr, stack_top(bfcr->stack)->base_class,
1175                         BFCR_STATE_NEXT_FIELD);
1176                 break;
1177         case BFCR_STATE_READ_BASIC_BEGIN:
1178                 status = read_basic_begin_state(bfcr);
1179                 break;
1180         case BFCR_STATE_READ_BASIC_CONTINUE:
1181                 status = read_basic_continue_state(bfcr);
1182                 break;
1183         case BFCR_STATE_DONE:
1184                 break;
1185         }
1186
1187         BT_COMP_LOGT("Handled state: bfcr-addr=%p, status=%s",
1188                 bfcr, bt_bfcr_status_string(status));
1189         return status;
1190 }
1191
1192 BT_HIDDEN
1193 struct bt_bfcr *bt_bfcr_create(struct bt_bfcr_cbs cbs, void *data,
1194                 bt_logging_level log_level, bt_self_component *self_comp)
1195 {
1196         struct bt_bfcr *bfcr;
1197
1198         BT_COMP_LOG_CUR_LVL(BT_LOG_DEBUG, log_level, self_comp,
1199                 "Creating binary field class reader (BFCR).");
1200         bfcr = g_new0(struct bt_bfcr, 1);
1201         if (!bfcr) {
1202                 BT_COMP_LOG_CUR_LVL(BT_LOG_ERROR, log_level, self_comp,
1203                         "Failed to allocate one binary class reader.");
1204                 goto end;
1205         }
1206
1207         bfcr->log_level = log_level;
1208         bfcr->self_comp = self_comp;
1209         bfcr->stack = stack_new(bfcr);
1210         if (!bfcr->stack) {
1211                 BT_COMP_LOGE_STR("Cannot create BFCR's stack.");
1212                 bt_bfcr_destroy(bfcr);
1213                 bfcr = NULL;
1214                 goto end;
1215         }
1216
1217         bfcr->state = BFCR_STATE_NEXT_FIELD;
1218         bfcr->user.cbs = cbs;
1219         bfcr->user.data = data;
1220         BT_COMP_LOGD("Created BFCR: addr=%p", bfcr);
1221
1222 end:
1223         return bfcr;
1224 }
1225
1226 BT_HIDDEN
1227 void bt_bfcr_destroy(struct bt_bfcr *bfcr)
1228 {
1229         if (bfcr->stack) {
1230                 stack_destroy(bfcr->stack);
1231         }
1232
1233         BT_COMP_LOGD("Destroying BFCR: addr=%p", bfcr);
1234         g_free(bfcr);
1235 }
1236
1237 static
1238 void reset(struct bt_bfcr *bfcr)
1239 {
1240         BT_COMP_LOGD("Resetting BFCR: addr=%p", bfcr);
1241         stack_clear(bfcr->stack);
1242         stitch_reset(bfcr);
1243         bfcr->buf.addr = NULL;
1244         bfcr->last_bo = -1;
1245 }
1246
1247 static
1248 void update_packet_offset(struct bt_bfcr *bfcr)
1249 {
1250         BT_COMP_LOGT("Updating packet offset for next call: "
1251                 "bfcr-addr=%p, cur-packet-offset=%zu, next-packet-offset=%zu",
1252                 bfcr, bfcr->buf.packet_offset,
1253                 bfcr->buf.packet_offset + bfcr->buf.at);
1254         bfcr->buf.packet_offset += bfcr->buf.at;
1255 }
1256
1257 BT_HIDDEN
1258 size_t bt_bfcr_start(struct bt_bfcr *bfcr,
1259         struct ctf_field_class *cls, const uint8_t *buf,
1260         size_t offset, size_t packet_offset, size_t sz,
1261         enum bt_bfcr_status *status)
1262 {
1263         BT_ASSERT(bfcr);
1264         BT_ASSERT(BYTES_TO_BITS(sz) >= offset);
1265         reset(bfcr);
1266         bfcr->buf.addr = buf;
1267         bfcr->buf.offset = offset;
1268         bfcr->buf.at = 0;
1269         bfcr->buf.packet_offset = packet_offset;
1270         bfcr->buf.buf_sz = sz;
1271         bfcr->buf.sz = BYTES_TO_BITS(sz) - offset;
1272         *status = BT_BFCR_STATUS_OK;
1273
1274         BT_COMP_LOGT("Starting decoding: bfcr-addr=%p, fc-addr=%p, "
1275                 "buf-addr=%p, buf-size=%zu, offset=%zu, "
1276                 "packet-offset=%zu",
1277                 bfcr, cls, buf, sz, offset, packet_offset);
1278
1279         /* Set root class */
1280         if (cls->is_compound) {
1281                 /* Compound class: push on visit stack */
1282                 int stack_ret;
1283
1284                 if (bfcr->user.cbs.classes.compound_begin) {
1285                         BT_COMP_LOGT("Calling user function (compound, begin).");
1286                         *status = bfcr->user.cbs.classes.compound_begin(
1287                                 cls, bfcr->user.data);
1288                         BT_COMP_LOGT("User function returned: status=%s",
1289                                 bt_bfcr_status_string(*status));
1290                         if (*status != BT_BFCR_STATUS_OK) {
1291                                 BT_COMP_LOGW("User function failed: bfcr-addr=%p, status=%s",
1292                                         bfcr, bt_bfcr_status_string(*status));
1293                                 goto end;
1294                         }
1295                 }
1296
1297                 stack_ret = stack_push_with_len(bfcr, cls);
1298                 if (stack_ret) {
1299                         /* stack_push_with_len() logs errors */
1300                         *status = BT_BFCR_STATUS_ERROR;
1301                         goto end;
1302                 }
1303
1304                 bfcr->state = BFCR_STATE_ALIGN_COMPOUND;
1305         } else {
1306                 /* Basic class: set as current basic class */
1307                 bfcr->cur_basic_field_class = cls;
1308                 bfcr->state = BFCR_STATE_ALIGN_BASIC;
1309         }
1310
1311         /* Run the machine! */
1312         BT_COMP_LOGT_STR("Running the state machine.");
1313
1314         while (true) {
1315                 *status = handle_state(bfcr);
1316                 if (*status != BT_BFCR_STATUS_OK ||
1317                                 bfcr->state == BFCR_STATE_DONE) {
1318                         break;
1319                 }
1320         }
1321
1322         /* Update packet offset for next time */
1323         update_packet_offset(bfcr);
1324
1325 end:
1326         return bfcr->buf.at;
1327 }
1328
1329 BT_HIDDEN
1330 size_t bt_bfcr_continue(struct bt_bfcr *bfcr, const uint8_t *buf, size_t sz,
1331                 enum bt_bfcr_status *status)
1332 {
1333         BT_ASSERT(bfcr);
1334         BT_ASSERT(buf);
1335         BT_ASSERT(sz > 0);
1336         bfcr->buf.addr = buf;
1337         bfcr->buf.offset = 0;
1338         bfcr->buf.at = 0;
1339         bfcr->buf.buf_sz = sz;
1340         bfcr->buf.sz = BYTES_TO_BITS(sz);
1341         *status = BT_BFCR_STATUS_OK;
1342
1343         BT_COMP_LOGT("Continuing decoding: bfcr-addr=%p, buf-addr=%p, buf-size=%zu",
1344                 bfcr, buf, sz);
1345
1346         /* Continue running the machine */
1347         BT_COMP_LOGT_STR("Running the state machine.");
1348
1349         while (true) {
1350                 *status = handle_state(bfcr);
1351                 if (*status != BT_BFCR_STATUS_OK ||
1352                                 bfcr->state == BFCR_STATE_DONE) {
1353                         break;
1354                 }
1355         }
1356
1357         /* Update packet offset for next time */
1358         update_packet_offset(bfcr);
1359         return bfcr->buf.at;
1360 }
1361
1362 BT_HIDDEN
1363 void bt_bfcr_set_unsigned_int_cb(struct bt_bfcr *bfcr,
1364                 bt_bfcr_unsigned_int_cb_func cb)
1365 {
1366         BT_ASSERT(bfcr);
1367         BT_ASSERT(cb);
1368         bfcr->user.cbs.classes.unsigned_int = cb;
1369 }