e2sm/lib/constr_CHOICE.c

   1 /*
   2  * Copyright (c) 2003-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
   3  * Redistribution and modifications are permitted subject to BSD license.
   4  */
   5 #include <asn_internal.h>
   6 #include <constr_CHOICE.h>
   7 #include <per_opentype.h>
   8
   9 /*
  10  * Number of bytes left for this structure.
  11  * (ctx->left) indicates the number of bytes _transferred_ for the structure.
  12  * (size) contains the number of bytes in the buffer passed.
  13  */
  14 #define LEFT    ((size<(size_t)ctx->left)?size:(size_t)ctx->left)
  15
  16 /*
  17  * If the subprocessor function returns with an indication that it wants
  18  * more data, it may well be a fatal decoding problem, because the
  19  * size is constrained by the <TLV>'s L, even if the buffer size allows
  20  * reading more data.
  21  * For example, consider the buffer containing the following TLVs:
  22  * <T:5><L:1><V> <T:6>...
  23  * The TLV length clearly indicates that one byte is expected in V, but
  24  * if the V processor returns with "want more data" even if the buffer
  25  * contains way more data than the V processor have seen.
  26  */
  27 #define SIZE_VIOLATION  (ctx->left >= 0 && (size_t)ctx->left <= size)
  28
  29 /*
  30  * This macro "eats" the part of the buffer which is definitely "consumed",
  31  * i.e. was correctly converted into local representation or rightfully skipped.
  32  */
  33 #undef  ADVANCE
  34 #define ADVANCE(num_bytes)      do {            \
  35                 size_t num = num_bytes;         \
  36                 ptr = ((const char *)ptr) + num;\
  37                 size -= num;                    \
  38                 if(ctx->left >= 0)              \
  39                         ctx->left -= num;       \
  40                 consumed_myself += num;         \
  41         } while(0)
  42
  43 /*
  44  * Switch to the next phase of parsing.
  45  */
  46 #undef  NEXT_PHASE
  47 #define NEXT_PHASE(ctx) do {                    \
  48                 ctx->phase++;                   \
  49                 ctx->step = 0;                  \
  50         } while(0)
  51
  52 /*
  53  * Return a standardized complex structure.
  54  */
  55 #undef  RETURN
  56 #define RETURN(_code)   do {                    \
  57                 rval.code = _code;              \
  58                 rval.consumed = consumed_myself;\
  59                 return rval;                    \
  60         } while(0)
  61
  62 /*
  63  * See the definitions.
  64  */
  65 static unsigned _fetch_present_idx(const void *struct_ptr, unsigned off,
  66                                    unsigned size);
  67 static void _set_present_idx(void *sptr, unsigned offset, unsigned size,
  68                              unsigned pres);
  69 static const void *_get_member_ptr(const asn_TYPE_descriptor_t *,
  70                                    const void *sptr, asn_TYPE_member_t **elm,
  71                                    unsigned *present);
  72
  73 /*
  74  * Tags are canonically sorted in the tag to member table.
  75  */
  76 static int
  77 _search4tag(const void *ap, const void *bp) {
  78         const asn_TYPE_tag2member_t *a = (const asn_TYPE_tag2member_t *)ap;
  79         const asn_TYPE_tag2member_t *b = (const asn_TYPE_tag2member_t *)bp;
  80
  81         int a_class = BER_TAG_CLASS(a->el_tag);
  82         int b_class = BER_TAG_CLASS(b->el_tag);
  83
  84         if(a_class == b_class) {
  85                 ber_tlv_tag_t a_value = BER_TAG_VALUE(a->el_tag);
  86                 ber_tlv_tag_t b_value = BER_TAG_VALUE(b->el_tag);
  87
  88                 if(a_value == b_value)
  89                         return 0;
  90                 else if(a_value < b_value)
  91                         return -1;
  92                 else
  93                         return 1;
  94         } else if(a_class < b_class) {
  95                 return -1;
  96         } else {
  97                 return 1;
  98         }
  99 }
 100
 101 /*
 102  * The decoder of the CHOICE type.
 103  */
 104 asn_dec_rval_t
 105 CHOICE_decode_ber(const asn_codec_ctx_t *opt_codec_ctx,
 106                   const asn_TYPE_descriptor_t *td, void **struct_ptr,
 107                   const void *ptr, size_t size, int tag_mode) {
 108     /*
 109          * Bring closer parts of structure description.
 110          */
 111         const asn_CHOICE_specifics_t *specs =
 112                 (const asn_CHOICE_specifics_t *)td->specifics;
 113         asn_TYPE_member_t *elements = td->elements;
 114
 115         /*
 116          * Parts of the structure being constructed.
 117          */
 118         void *st = *struct_ptr; /* Target structure. */
 119         asn_struct_ctx_t *ctx;  /* Decoder context */
 120
 121         ber_tlv_tag_t tlv_tag;  /* T from TLV */
 122         ssize_t tag_len;        /* Length of TLV's T */
 123         asn_dec_rval_t rval;    /* Return code from subparsers */
 124
 125         ssize_t consumed_myself = 0;    /* Consumed bytes from ptr */
 126
 127         ASN_DEBUG("Decoding %s as CHOICE", td->name);
 128
 129         /*
 130          * Create the target structure if it is not present already.
 131          */
 132         if(st == 0) {
 133                 st = *struct_ptr = CALLOC(1, specs->struct_size);
 134                 if(st == 0) {
 135                         RETURN(RC_FAIL);
 136                 }
 137         }
 138
 139         /*
 140          * Restore parsing context.
 141          */
 142         ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);
 143
 144         /*
 145          * Start to parse where left previously
 146          */
 147         switch(ctx->phase) {
 148         case 0:
 149                 /*
 150                  * PHASE 0.
 151                  * Check that the set of tags associated with given structure
 152                  * perfectly fits our expectations.
 153                  */
 154
 155                 if(tag_mode || td->tags_count) {
 156                         rval = ber_check_tags(opt_codec_ctx, td, ctx, ptr, size,
 157                                 tag_mode, -1, &ctx->left, 0);
 158                         if(rval.code != RC_OK) {
 159                                 ASN_DEBUG("%s tagging check failed: %d",
 160                                         td->name, rval.code);
 161                                 return rval;
 162                         }
 163
 164                         if(ctx->left >= 0) {
 165                                 /* ?Substracted below! */
 166                                 ctx->left += rval.consumed;
 167                         }
 168                         ADVANCE(rval.consumed);
 169                 } else {
 170                         ctx->left = -1;
 171                 }
 172
 173                 NEXT_PHASE(ctx);
 174
 175                 ASN_DEBUG("Structure consumes %ld bytes, buffer %ld",
 176                         (long)ctx->left, (long)size);
 177
 178                 /* Fall through */
 179         case 1:
 180                 /*
 181                  * Fetch the T from TLV.
 182                  */
 183                 tag_len = ber_fetch_tag(ptr, LEFT, &tlv_tag);
 184                 ASN_DEBUG("In %s CHOICE tag length %d", td->name, (int)tag_len);
 185                 switch(tag_len) {
 186                 case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
 187                         /* Fall through */
 188                 case -1: RETURN(RC_FAIL);
 189                 }
 190
 191                 do {
 192                         const asn_TYPE_tag2member_t *t2m;
 193                         asn_TYPE_tag2member_t key;
 194
 195                         key.el_tag = tlv_tag;
 196                         t2m = (const asn_TYPE_tag2member_t *)bsearch(&key,
 197                                         specs->tag2el, specs->tag2el_count,
 198                                         sizeof(specs->tag2el[0]), _search4tag);
 199                         if(t2m) {
 200                                 /*
 201                                  * Found the element corresponding to the tag.
 202                                  */
 203                                 NEXT_PHASE(ctx);
 204                                 ctx->step = t2m->el_no;
 205                                 break;
 206                         } else if(specs->ext_start == -1) {
 207                                 ASN_DEBUG("Unexpected tag %s "
 208                                         "in non-extensible CHOICE %s",
 209                                         ber_tlv_tag_string(tlv_tag), td->name);
 210                                 RETURN(RC_FAIL);
 211                         } else {
 212                                 /* Skip this tag */
 213                                 ssize_t skip;
 214
 215                                 ASN_DEBUG("Skipping unknown tag %s",
 216                                         ber_tlv_tag_string(tlv_tag));
 217
 218                                 skip = ber_skip_length(opt_codec_ctx,
 219                                         BER_TLV_CONSTRUCTED(ptr),
 220                                         (const char *)ptr + tag_len,
 221                                         LEFT - tag_len);
 222
 223                                 switch(skip) {
 224                                 case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
 225                                         /* Fall through */
 226                                 case -1: RETURN(RC_FAIL);
 227                                 }
 228
 229                                 ADVANCE(skip + tag_len);
 230                                 RETURN(RC_OK);
 231                         }
 232                 } while(0);
 233
 234         case 2:
 235                 /*
 236                  * PHASE 2.
 237                  * Read in the element.
 238                  */
 239             do {
 240                 asn_TYPE_member_t *elm;/* CHOICE's element */
 241                 void *memb_ptr;         /* Pointer to the member */
 242                 void **memb_ptr2;       /* Pointer to that pointer */
 243
 244                 elm = &elements[ctx->step];
 245
 246                 /*
 247                  * Compute the position of the member inside a structure,
 248                  * and also a type of containment (it may be contained
 249                  * as pointer or using inline inclusion).
 250                  */
 251                 if(elm->flags & ATF_POINTER) {
 252                         /* Member is a pointer to another structure */
 253                         memb_ptr2 = (void **)((char *)st + elm->memb_offset);
 254                 } else {
 255                         /*
 256                          * A pointer to a pointer
 257                          * holding the start of the structure
 258                          */
 259                         memb_ptr = (char *)st + elm->memb_offset;
 260                         memb_ptr2 = &memb_ptr;
 261                 }
 262                 /* Set presence to be able to free it properly at any time */
 263                 _set_present_idx(st, specs->pres_offset,
 264                                 specs->pres_size, ctx->step + 1);
 265                 /*
 266                  * Invoke the member fetch routine according to member's type
 267                  */
 268                 rval = elm->type->op->ber_decoder(opt_codec_ctx, elm->type,
 269                                 memb_ptr2, ptr, LEFT, elm->tag_mode);
 270                 switch(rval.code) {
 271                 case RC_OK:
 272                         break;
 273                 case RC_WMORE: /* More data expected */
 274                         if(!SIZE_VIOLATION) {
 275                                 ADVANCE(rval.consumed);
 276                                 RETURN(RC_WMORE);
 277                         }
 278                         RETURN(RC_FAIL);
 279                 case RC_FAIL: /* Fatal error */
 280                         RETURN(rval.code);
 281                 } /* switch(rval) */
 282
 283                 ADVANCE(rval.consumed);
 284           } while(0);
 285
 286                 NEXT_PHASE(ctx);
 287
 288                 /* Fall through */
 289         case 3:
 290                 ASN_DEBUG("CHOICE %s Leftover: %ld, size = %ld, tm=%d, tc=%d",
 291                         td->name, (long)ctx->left, (long)size,
 292                         tag_mode, td->tags_count);
 293
 294                 if(ctx->left > 0) {
 295                         /*
 296                          * The type must be fully decoded
 297                          * by the CHOICE member-specific decoder.
 298                          */
 299                         RETURN(RC_FAIL);
 300                 }
 301
 302                 if(ctx->left == -1
 303                 && !(tag_mode || td->tags_count)) {
 304                         /*
 305                          * This is an untagged CHOICE.
 306                          * It doesn't contain nothing
 307                          * except for the member itself, including all its tags.
 308                          * The decoding is completed.
 309                          */
 310                         NEXT_PHASE(ctx);
 311                         break;
 312                 }
 313
 314                 /*
 315                  * Read in the "end of data chunks"'s.
 316                  */
 317                 while(ctx->left < 0) {
 318                         ssize_t tl;
 319
 320                         tl = ber_fetch_tag(ptr, LEFT, &tlv_tag);
 321                         switch(tl) {
 322                         case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
 323                                 /* Fall through */
 324                         case -1: RETURN(RC_FAIL);
 325                         }
 326
 327                         /*
 328                          * Expected <0><0>...
 329                          */
 330                         if(((const uint8_t *)ptr)[0] == 0) {
 331                                 if(LEFT < 2) {
 332                                         if(SIZE_VIOLATION)
 333                                                 RETURN(RC_FAIL);
 334                                         else
 335                                                 RETURN(RC_WMORE);
 336                                 } else if(((const uint8_t *)ptr)[1] == 0) {
 337                                         /*
 338                                          * Correctly finished with <0><0>.
 339                                          */
 340                                         ADVANCE(2);
 341                                         ctx->left++;
 342                                         continue;
 343                                 }
 344                         } else {
 345                                 ASN_DEBUG("Unexpected continuation in %s",
 346                                         td->name);
 347                                 RETURN(RC_FAIL);
 348                         }
 349
 350                         /* UNREACHABLE */
 351                 }
 352
 353                 NEXT_PHASE(ctx);
 354         case 4:
 355                 /* No meaningful work here */
 356                 break;
 357         }
 358
 359         RETURN(RC_OK);
 360 }
 361
 362 asn_enc_rval_t
 363 CHOICE_encode_der(const asn_TYPE_descriptor_t *td, const void *sptr,
 364                   int tag_mode, ber_tlv_tag_t tag, asn_app_consume_bytes_f *cb,
 365                   void *app_key) {
 366     const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
 367         asn_TYPE_member_t *elm; /* CHOICE element */
 368         asn_enc_rval_t erval = {0,0,0};
 369         const void *memb_ptr;
 370         size_t computed_size = 0;
 371         unsigned present;
 372
 373         if(!sptr) ASN__ENCODE_FAILED;
 374
 375         ASN_DEBUG("%s %s as CHOICE",
 376                 cb?"Encoding":"Estimating", td->name);
 377
 378         present = _fetch_present_idx(sptr,
 379                 specs->pres_offset, specs->pres_size);
 380
 381         /*
 382          * If the structure was not initialized, it cannot be encoded:
 383          * can't deduce what to encode in the choice type.
 384          */
 385         if(present == 0 || present > td->elements_count) {
 386                 if(present == 0 && td->elements_count == 0) {
 387                         /* The CHOICE is empty?! */
 388                         erval.encoded = 0;
 389                         ASN__ENCODED_OK(erval);
 390                 }
 391                 ASN__ENCODE_FAILED;
 392         }
 393
 394         /*
 395          * Seek over the present member of the structure.
 396          */
 397         elm = &td->elements[present-1];
 398         if(elm->flags & ATF_POINTER) {
 399         memb_ptr =
 400             *(const void *const *)((const char *)sptr + elm->memb_offset);
 401         if(memb_ptr == 0) {
 402                         if(elm->optional) {
 403                                 erval.encoded = 0;
 404                                 ASN__ENCODED_OK(erval);
 405                         }
 406                         /* Mandatory element absent */
 407                         ASN__ENCODE_FAILED;
 408                 }
 409         } else {
 410         memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
 411     }
 412
 413         /*
 414          * If the CHOICE itself is tagged EXPLICIT:
 415          * T ::= [2] EXPLICIT CHOICE { ... }
 416          * Then emit the appropriate tags.
 417          */
 418         if(tag_mode == 1 || td->tags_count) {
 419                 /*
 420                  * For this, we need to pre-compute the member.
 421                  */
 422                 ssize_t ret;
 423
 424                 /* Encode member with its tag */
 425                 erval = elm->type->op->der_encoder(elm->type, memb_ptr,
 426                         elm->tag_mode, elm->tag, 0, 0);
 427                 if(erval.encoded == -1)
 428                         return erval;
 429
 430                 /* Encode CHOICE with parent or my own tag */
 431                 ret = der_write_tags(td, erval.encoded, tag_mode, 1, tag,
 432                         cb, app_key);
 433                 if(ret == -1)
 434                         ASN__ENCODE_FAILED;
 435                 computed_size += ret;
 436         }
 437
 438         /*
 439          * Encode the single underlying member.
 440          */
 441         erval = elm->type->op->der_encoder(elm->type, memb_ptr,
 442                 elm->tag_mode, elm->tag, cb, app_key);
 443         if(erval.encoded == -1)
 444                 return erval;
 445
 446         ASN_DEBUG("Encoded CHOICE member in %ld bytes (+%ld)",
 447                 (long)erval.encoded, (long)computed_size);
 448
 449         erval.encoded += computed_size;
 450
 451         return erval;
 452 }
 453
 454 ber_tlv_tag_t
 455 CHOICE_outmost_tag(const asn_TYPE_descriptor_t *td, const void *ptr, int tag_mode, ber_tlv_tag_t tag) {
 456         const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
 457         unsigned present;
 458
 459         assert(tag_mode == 0); (void)tag_mode;
 460         assert(tag == 0); (void)tag;
 461
 462         /*
 463          * Figure out which CHOICE element is encoded.
 464          */
 465         present = _fetch_present_idx(ptr, specs->pres_offset, specs->pres_size);
 466
 467         if(present > 0 && present <= td->elements_count) {
 468                 const asn_TYPE_member_t *elm = &td->elements[present-1];
 469                 const void *memb_ptr;
 470
 471                 if(elm->flags & ATF_POINTER) {
 472                         memb_ptr = *(const void * const *)
 473                                         ((const char *)ptr + elm->memb_offset);
 474                 } else {
 475                         memb_ptr = (const void *)
 476                                         ((const char *)ptr + elm->memb_offset);
 477                 }
 478
 479                 return asn_TYPE_outmost_tag(elm->type, memb_ptr,
 480                         elm->tag_mode, elm->tag);
 481         } else {
 482                 return (ber_tlv_tag_t)-1;
 483         }
 484 }
 485
 486 int
 487 CHOICE_constraint(const asn_TYPE_descriptor_t *td, const void *sptr,
 488                   asn_app_constraint_failed_f *ctfailcb, void *app_key) {
 489     const asn_CHOICE_specifics_t *specs =
 490         (const asn_CHOICE_specifics_t *)td->specifics;
 491     unsigned present;
 492
 493         if(!sptr) {
 494                 ASN__CTFAIL(app_key, td, sptr,
 495                         "%s: value not given (%s:%d)",
 496                         td->name, __FILE__, __LINE__);
 497                 return -1;
 498         }
 499
 500         /*
 501          * Figure out which CHOICE element is encoded.
 502          */
 503         present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);
 504         if(present > 0 && present <= td->elements_count) {
 505                 asn_TYPE_member_t *elm = &td->elements[present-1];
 506                 const void *memb_ptr;
 507
 508                 if(elm->flags & ATF_POINTER) {
 509                         memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
 510                         if(!memb_ptr) {
 511                                 if(elm->optional)
 512                                         return 0;
 513                                 ASN__CTFAIL(app_key, td, sptr,
 514                                         "%s: mandatory CHOICE element %s absent (%s:%d)",
 515                                         td->name, elm->name, __FILE__, __LINE__);
 516                                 return -1;
 517                         }
 518                 } else {
 519                         memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
 520                 }
 521
 522                 if(elm->encoding_constraints.general_constraints) {
 523                         return elm->encoding_constraints.general_constraints(elm->type, memb_ptr,
 524                                 ctfailcb, app_key);
 525                 } else {
 526                         return elm->type->encoding_constraints.general_constraints(elm->type,
 527                                         memb_ptr, ctfailcb, app_key);
 528                 }
 529         } else {
 530                 ASN__CTFAIL(app_key, td, sptr,
 531                         "%s: no CHOICE element given (%s:%d)",
 532                         td->name, __FILE__, __LINE__);
 533                 return -1;
 534         }
 535 }
 536
 537 #undef  XER_ADVANCE
 538 #define XER_ADVANCE(num_bytes)  do {                    \
 539                 size_t num = num_bytes;                 \
 540                 buf_ptr = (const void *)(((const char *)buf_ptr) + num); \
 541                 size -= num;                            \
 542                 consumed_myself += num;                 \
 543         } while(0)
 544
 545 /*
 546  * Decode the XER (XML) data.
 547  */
 548 asn_dec_rval_t
 549 CHOICE_decode_xer(const asn_codec_ctx_t *opt_codec_ctx,
 550                   const asn_TYPE_descriptor_t *td, void **struct_ptr,
 551                   const char *opt_mname, const void *buf_ptr, size_t size) {
 552     /*
 553          * Bring closer parts of structure description.
 554          */
 555         const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
 556         const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;
 557
 558         /*
 559          * Parts of the structure being constructed.
 560          */
 561         void *st = *struct_ptr; /* Target structure. */
 562         asn_struct_ctx_t *ctx;  /* Decoder context */
 563
 564         asn_dec_rval_t rval;            /* Return value of a decoder */
 565         ssize_t consumed_myself = 0;    /* Consumed bytes from ptr */
 566         size_t edx;                     /* Element index */
 567
 568         /*
 569          * Create the target structure if it is not present already.
 570          */
 571         if(st == 0) {
 572                 st = *struct_ptr = CALLOC(1, specs->struct_size);
 573                 if(st == 0) RETURN(RC_FAIL);
 574         }
 575
 576         /*
 577          * Restore parsing context.
 578          */
 579         ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);
 580         if(ctx->phase == 0 && !*xml_tag)
 581                 ctx->phase = 1; /* Skip the outer tag checking phase */
 582
 583         /*
 584          * Phases of XER/XML processing:
 585          * Phase 0: Check that the opening tag matches our expectations.
 586          * Phase 1: Processing body and reacting on closing tag.
 587          * Phase 2: Processing inner type.
 588          * Phase 3: Only waiting for closing tag.
 589          * Phase 4: Skipping unknown extensions.
 590          * Phase 5: PHASED OUT
 591          */
 592         for(edx = ctx->step; ctx->phase <= 4;) {
 593                 pxer_chunk_type_e ch_type;      /* XER chunk type */
 594                 ssize_t ch_size;                /* Chunk size */
 595                 xer_check_tag_e tcv;            /* Tag check value */
 596                 asn_TYPE_member_t *elm;
 597
 598                 /*
 599                  * Go inside the member.
 600                  */
 601                 if(ctx->phase == 2) {
 602                         asn_dec_rval_t tmprval;
 603                         void *memb_ptr;         /* Pointer to the member */
 604                         void **memb_ptr2;       /* Pointer to that pointer */
 605                         unsigned old_present;
 606
 607                         elm = &td->elements[edx];
 608
 609                         if(elm->flags & ATF_POINTER) {
 610                                 /* Member is a pointer to another structure */
 611                                 memb_ptr2 = (void **)((char *)st
 612                                         + elm->memb_offset);
 613                         } else {
 614                                 memb_ptr = (char *)st + elm->memb_offset;
 615                                 memb_ptr2 = &memb_ptr;
 616                         }
 617
 618                         /* Start/Continue decoding the inner member */
 619                         tmprval = elm->type->op->xer_decoder(opt_codec_ctx,
 620                                         elm->type, memb_ptr2, elm->name,
 621                                         buf_ptr, size);
 622                         XER_ADVANCE(tmprval.consumed);
 623                         ASN_DEBUG("XER/CHOICE: itdf: [%s] code=%d",
 624                                 elm->type->name, tmprval.code);
 625                         old_present = _fetch_present_idx(st,
 626                                 specs->pres_offset, specs->pres_size);
 627                         assert(old_present == 0 || old_present == edx + 1);
 628                         /* Record what we've got */
 629                         _set_present_idx(st,
 630                                 specs->pres_offset, specs->pres_size, edx + 1);
 631                         if(tmprval.code != RC_OK)
 632                                 RETURN(tmprval.code);
 633                         ctx->phase = 3;
 634                         /* Fall through */
 635                 }
 636
 637                 /* No need to wait for closing tag; special mode. */
 638                 if(ctx->phase == 3 && !*xml_tag) {
 639                         ctx->phase = 5; /* Phase out */
 640                         RETURN(RC_OK);
 641                 }
 642
 643                 /*
 644                  * Get the next part of the XML stream.
 645                  */
 646                 ch_size = xer_next_token(&ctx->context, buf_ptr, size, &ch_type);
 647                 if(ch_size == -1) {
 648             RETURN(RC_FAIL);
 649         } else {
 650                         switch(ch_type) {
 651                         case PXER_WMORE:
 652                 RETURN(RC_WMORE);
 653                         case PXER_COMMENT:      /* Got XML comment */
 654                         case PXER_TEXT:         /* Ignore free-standing text */
 655                                 XER_ADVANCE(ch_size);   /* Skip silently */
 656                                 continue;
 657                         case PXER_TAG:
 658                                 break;  /* Check the rest down there */
 659                         }
 660                 }
 661
 662                 tcv = xer_check_tag(buf_ptr, ch_size, xml_tag);
 663                 ASN_DEBUG("XER/CHOICE checked [%c%c%c%c] vs [%s], tcv=%d",
 664                         ch_size>0?((const uint8_t *)buf_ptr)[0]:'?',
 665                         ch_size>1?((const uint8_t *)buf_ptr)[1]:'?',
 666                         ch_size>2?((const uint8_t *)buf_ptr)[2]:'?',
 667                         ch_size>3?((const uint8_t *)buf_ptr)[3]:'?',
 668                 xml_tag, tcv);
 669
 670                 /* Skip the extensions section */
 671                 if(ctx->phase == 4) {
 672                         ASN_DEBUG("skip_unknown(%d, %ld)",
 673                                 tcv, (long)ctx->left);
 674                         switch(xer_skip_unknown(tcv, &ctx->left)) {
 675                         case -1:
 676                                 ctx->phase = 5;
 677                                 RETURN(RC_FAIL);
 678                         case 1:
 679                                 ctx->phase = 3;
 680                                 /* Fall through */
 681                         case 0:
 682                                 XER_ADVANCE(ch_size);
 683                                 continue;
 684                         case 2:
 685                                 ctx->phase = 3;
 686                                 break;
 687                         }
 688                 }
 689
 690                 switch(tcv) {
 691                 case XCT_BOTH:
 692                         break;  /* No CHOICE? */
 693                 case XCT_CLOSING:
 694                         if(ctx->phase != 3)
 695                                 break;
 696                         XER_ADVANCE(ch_size);
 697                         ctx->phase = 5; /* Phase out */
 698                         RETURN(RC_OK);
 699                 case XCT_OPENING:
 700                         if(ctx->phase == 0) {
 701                                 XER_ADVANCE(ch_size);
 702                                 ctx->phase = 1; /* Processing body phase */
 703                                 continue;
 704                         }
 705                         /* Fall through */
 706                 case XCT_UNKNOWN_OP:
 707                 case XCT_UNKNOWN_BO:
 708
 709                         if(ctx->phase != 1)
 710                                 break;  /* Really unexpected */
 711
 712                         /*
 713                          * Search which inner member corresponds to this tag.
 714                          */
 715                         for(edx = 0; edx < td->elements_count; edx++) {
 716                                 elm = &td->elements[edx];
 717                                 tcv = xer_check_tag(buf_ptr,ch_size,elm->name);
 718                                 switch(tcv) {
 719                                 case XCT_BOTH:
 720                                 case XCT_OPENING:
 721                                         /*
 722                                          * Process this member.
 723                                          */
 724                                         ctx->step = edx;
 725                                         ctx->phase = 2;
 726                                         break;
 727                                 case XCT_UNKNOWN_OP:
 728                                 case XCT_UNKNOWN_BO:
 729                                         continue;
 730                                 default:
 731                                         edx = td->elements_count;
 732                                         break;  /* Phase out */
 733                                 }
 734                                 break;
 735                         }
 736                         if(edx != td->elements_count)
 737                                 continue;
 738
 739                         /* It is expected extension */
 740                         if(specs->ext_start != -1) {
 741                                 ASN_DEBUG("Got anticipated extension");
 742                                 /*
 743                                  * Check for (XCT_BOTH or XCT_UNKNOWN_BO)
 744                                  * By using a mask. Only record a pure
 745                                  * <opening> tags.
 746                                  */
 747                                 if(tcv & XCT_CLOSING) {
 748                                         /* Found </extension> without body */
 749                                         ctx->phase = 3; /* Terminating */
 750                                 } else {
 751                                         ctx->left = 1;
 752                                         ctx->phase = 4; /* Skip ...'s */
 753                                 }
 754                                 XER_ADVANCE(ch_size);
 755                                 continue;
 756                         }
 757
 758                         /* Fall through */
 759                 default:
 760                         break;
 761                 }
 762
 763                 ASN_DEBUG("Unexpected XML tag [%c%c%c%c] in CHOICE [%s]"
 764                         " (ph=%d, tag=%s)",
 765                         ch_size>0?((const uint8_t *)buf_ptr)[0]:'?',
 766                         ch_size>1?((const uint8_t *)buf_ptr)[1]:'?',
 767                         ch_size>2?((const uint8_t *)buf_ptr)[2]:'?',
 768                         ch_size>3?((const uint8_t *)buf_ptr)[3]:'?',
 769                         td->name, ctx->phase, xml_tag);
 770                 break;
 771         }
 772
 773         ctx->phase = 5; /* Phase out, just in case */
 774         RETURN(RC_FAIL);
 775 }
 776
 777
 778 asn_enc_rval_t
 779 CHOICE_encode_xer(const asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
 780                   enum xer_encoder_flags_e flags, asn_app_consume_bytes_f *cb,
 781                   void *app_key) {
 782         const asn_CHOICE_specifics_t *specs =
 783                 (const asn_CHOICE_specifics_t *)td->specifics;
 784         asn_enc_rval_t er = {0,0,0};
 785         unsigned present = 0;
 786
 787         if(!sptr)
 788                 ASN__ENCODE_FAILED;
 789
 790         /*
 791          * Figure out which CHOICE element is encoded.
 792          */
 793         present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);
 794
 795         if(present == 0 || present > td->elements_count) {
 796                 ASN__ENCODE_FAILED;
 797         }  else {
 798                 asn_enc_rval_t tmper = {0,0,0};
 799                 asn_TYPE_member_t *elm = &td->elements[present-1];
 800                 const void *memb_ptr = NULL;
 801                 const char *mname = elm->name;
 802                 unsigned int mlen = strlen(mname);
 803
 804                 if(elm->flags & ATF_POINTER) {
 805             memb_ptr =
 806                 *(const void *const *)((const char *)sptr + elm->memb_offset);
 807             if(!memb_ptr) ASN__ENCODE_FAILED;
 808                 } else {
 809             memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
 810         }
 811
 812         er.encoded = 0;
 813
 814                 if(!(flags & XER_F_CANONICAL)) ASN__TEXT_INDENT(1, ilevel);
 815                 ASN__CALLBACK3("<", 1, mname, mlen, ">", 1);
 816
 817                 tmper = elm->type->op->xer_encoder(elm->type, memb_ptr,
 818                                 ilevel + 1, flags, cb, app_key);
 819                 if(tmper.encoded == -1) return tmper;
 820                 er.encoded += tmper.encoded;
 821
 822                 ASN__CALLBACK3("</", 2, mname, mlen, ">", 1);
 823         }
 824
 825         if(!(flags & XER_F_CANONICAL)) ASN__TEXT_INDENT(1, ilevel - 1);
 826
 827         ASN__ENCODED_OK(er);
 828 cb_failed:
 829         ASN__ENCODE_FAILED;
 830 }
 831
 832 asn_dec_rval_t
 833 CHOICE_decode_uper(const asn_codec_ctx_t *opt_codec_ctx,
 834                    const asn_TYPE_descriptor_t *td,
 835                    const asn_per_constraints_t *constraints, void **sptr,
 836                    asn_per_data_t *pd) {
 837     const asn_CHOICE_specifics_t *specs =
 838         (const asn_CHOICE_specifics_t *)td->specifics;
 839     asn_dec_rval_t rv;
 840         const asn_per_constraint_t *ct;
 841         asn_TYPE_member_t *elm; /* CHOICE's element */
 842         void *memb_ptr;
 843         void **memb_ptr2;
 844         void *st = *sptr;
 845         int value;
 846
 847         if(ASN__STACK_OVERFLOW_CHECK(opt_codec_ctx))
 848                 ASN__DECODE_FAILED;
 849
 850         /*
 851          * Create the target structure if it is not present already.
 852          */
 853         if(!st) {
 854                 st = *sptr = CALLOC(1, specs->struct_size);
 855                 if(!st) ASN__DECODE_FAILED;
 856         }
 857
 858         if(constraints) ct = &constraints->value;
 859         else if(td->encoding_constraints.per_constraints) ct = &td->encoding_constraints.per_constraints->value;
 860         else ct = 0;
 861
 862         if(ct && ct->flags & APC_EXTENSIBLE) {
 863                 value = per_get_few_bits(pd, 1);
 864                 if(value < 0) ASN__DECODE_STARVED;
 865                 if(value) ct = 0;       /* Not restricted */
 866         }
 867
 868         if(ct && ct->range_bits >= 0) {
 869                 value = per_get_few_bits(pd, ct->range_bits);
 870                 if(value < 0) ASN__DECODE_STARVED;
 871                 ASN_DEBUG("CHOICE %s got index %d in range %d",
 872                         td->name, value, ct->range_bits);
 873                 if(value > ct->upper_bound)
 874                         ASN__DECODE_FAILED;
 875         } else {
 876                 if(specs->ext_start == -1)
 877                         ASN__DECODE_FAILED;
 878                 value = uper_get_nsnnwn(pd);
 879                 if(value < 0) ASN__DECODE_STARVED;
 880                 value += specs->ext_start;
 881                 if((unsigned)value >= td->elements_count)
 882                         ASN__DECODE_FAILED;
 883         }
 884
 885         /* Adjust if canonical order is different from natural order */
 886         if(specs->from_canonical_order) {
 887         ASN_DEBUG("CHOICE presence from wire %d", value);
 888                 value = specs->from_canonical_order[value];
 889         ASN_DEBUG("CHOICE presence index effective %d", value);
 890     }
 891
 892         /* Set presence to be able to free it later */
 893         _set_present_idx(st, specs->pres_offset, specs->pres_size, value + 1);
 894
 895         elm = &td->elements[value];
 896         if(elm->flags & ATF_POINTER) {
 897                 /* Member is a pointer to another structure */
 898                 memb_ptr2 = (void **)((char *)st + elm->memb_offset);
 899         } else {
 900                 memb_ptr = (char *)st + elm->memb_offset;
 901                 memb_ptr2 = &memb_ptr;
 902         }
 903         ASN_DEBUG("Discovered CHOICE %s encodes %s", td->name, elm->name);
 904
 905         if(ct && ct->range_bits >= 0) {
 906                 rv = elm->type->op->uper_decoder(opt_codec_ctx, elm->type,
 907                         elm->encoding_constraints.per_constraints, memb_ptr2, pd);
 908         } else {
 909                 rv = uper_open_type_get(opt_codec_ctx, elm->type,
 910                         elm->encoding_constraints.per_constraints, memb_ptr2, pd);
 911         }
 912
 913         if(rv.code != RC_OK)
 914                 ASN_DEBUG("Failed to decode %s in %s (CHOICE) %d",
 915                         elm->name, td->name, rv.code);
 916         return rv;
 917 }
 918
 919 asn_enc_rval_t
 920 CHOICE_encode_uper(const asn_TYPE_descriptor_t *td,
 921                    const asn_per_constraints_t *constraints, const void *sptr,
 922                    asn_per_outp_t *po) {
 923         const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
 924         asn_TYPE_member_t *elm; /* CHOICE's element */
 925         const asn_per_constraint_t *ct;
 926         const void *memb_ptr;
 927         unsigned present;
 928         int present_enc;
 929
 930         if(!sptr) ASN__ENCODE_FAILED;
 931
 932         ASN_DEBUG("Encoding %s as CHOICE", td->name);
 933
 934         if(constraints) ct = &constraints->value;
 935         else if(td->encoding_constraints.per_constraints)
 936                 ct = &td->encoding_constraints.per_constraints->value;
 937         else ct = 0;
 938
 939         present = _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
 940
 941         /*
 942          * If the structure was not initialized properly, it cannot be encoded:
 943          * can't deduce what to encode in the choice type.
 944          */
 945         if(present == 0 || present > td->elements_count)
 946                 ASN__ENCODE_FAILED;
 947         else
 948                 present--;
 949
 950         ASN_DEBUG("Encoding %s CHOICE element %d", td->name, present);
 951
 952     /* Adjust if canonical order is different from natural order */
 953     if(specs->to_canonical_order)
 954         present_enc = specs->to_canonical_order[present];
 955     else
 956         present_enc = present;
 957
 958     if(ct && ct->range_bits >= 0) {
 959                 if(present_enc < ct->lower_bound
 960                 || present_enc > ct->upper_bound) {
 961                         if(ct->flags & APC_EXTENSIBLE) {
 962                 ASN_DEBUG(
 963                     "CHOICE member %d (enc %d) is an extension (%ld..%ld)",
 964                     present, present_enc, ct->lower_bound, ct->upper_bound);
 965                 if(per_put_few_bits(po, 1, 1))
 966                                         ASN__ENCODE_FAILED;
 967                         } else {
 968                                 ASN__ENCODE_FAILED;
 969                         }
 970                         ct = 0;
 971                 }
 972         }
 973         if(ct && ct->flags & APC_EXTENSIBLE) {
 974         ASN_DEBUG("CHOICE member %d (enc %d) is not an extension (%ld..%ld)",
 975                   present, present_enc, ct->lower_bound, ct->upper_bound);
 976         if(per_put_few_bits(po, 0, 1))
 977                         ASN__ENCODE_FAILED;
 978     }
 979
 980
 981         elm = &td->elements[present];
 982     ASN_DEBUG("CHOICE member \"%s\" %d (as %d)", elm->name, present,
 983               present_enc);
 984     if(elm->flags & ATF_POINTER) {
 985                 /* Member is a pointer to another structure */
 986         memb_ptr =
 987             *(const void *const *)((const char *)sptr + elm->memb_offset);
 988         if(!memb_ptr) ASN__ENCODE_FAILED;
 989         } else {
 990         memb_ptr = (const char *)sptr + elm->memb_offset;
 991     }
 992
 993     if(ct && ct->range_bits >= 0) {
 994         if(per_put_few_bits(po, present_enc, ct->range_bits))
 995             ASN__ENCODE_FAILED;
 996
 997         return elm->type->op->uper_encoder(
 998             elm->type, elm->encoding_constraints.per_constraints, memb_ptr, po);
 999     } else {
1000         asn_enc_rval_t rval = {0,0,0};
1001         if(specs->ext_start == -1) ASN__ENCODE_FAILED;
1002         if(uper_put_nsnnwn(po, present_enc - specs->ext_start))
1003             ASN__ENCODE_FAILED;
1004         if(uper_open_type_put(elm->type,
1005                               elm->encoding_constraints.per_constraints,
1006                               memb_ptr, po))
1007             ASN__ENCODE_FAILED;
1008         rval.encoded = 0;
1009         ASN__ENCODED_OK(rval);
1010     }
1011 }
1012
1013 asn_dec_rval_t
1014 CHOICE_decode_aper(const asn_codec_ctx_t *opt_codec_ctx,
1015                    const asn_TYPE_descriptor_t *td,
1016                    const asn_per_constraints_t *constraints, void **sptr, asn_per_data_t *pd) {
1017         const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
1018         asn_dec_rval_t rv;
1019         const asn_per_constraint_t *ct;
1020         const asn_per_constraint_t *ext_ct = NULL;
1021         asn_TYPE_member_t *elm; /* CHOICE's element */
1022         void *memb_ptr;
1023         void **memb_ptr2;
1024         void *st = *sptr;
1025         int value;
1026
1027         if(ASN__STACK_OVERFLOW_CHECK(opt_codec_ctx))
1028                 ASN__DECODE_FAILED;
1029
1030         /*
1031          * Create the target structure if it is not present already.
1032          */
1033         if(!st) {
1034                 st = *sptr = CALLOC(1, specs->struct_size);
1035                 if(!st) ASN__DECODE_FAILED;
1036         }
1037
1038         if(constraints) ct = &constraints->value;
1039         else if(td->encoding_constraints.per_constraints)
1040                 ct = &td->encoding_constraints.per_constraints->value;
1041         else ct = 0;
1042
1043         if(ct && ct->flags & APC_EXTENSIBLE) {
1044                 value = per_get_few_bits(pd, 1);
1045                 if(value < 0) ASN__DECODE_STARVED;
1046                 if(value) {
1047                   ext_ct = ct;
1048                   ct = 0;       /* Not restricted */
1049                 }
1050         }
1051
1052
1053         if(ct && ct->range_bits >= 0) {
1054                 value = per_get_few_bits(pd, ct->range_bits);
1055                 if(value < 0) ASN__DECODE_STARVED;
1056                 ASN_DEBUG("CHOICE %s got index %d in range %d",
1057                           td->name, value, ct->range_bits);
1058                 if(value > ct->upper_bound)
1059                         ASN__DECODE_FAILED;
1060         } else {
1061                 if(specs->ext_start == -1)
1062                         ASN__DECODE_FAILED;
1063                 value = aper_get_nsnnwn(pd, ext_ct->range_bits);
1064                 if(value < 0) ASN__DECODE_STARVED;
1065                 value += specs->ext_start;
1066                 if((unsigned)value >= td->elements_count)
1067                         ASN__DECODE_FAILED;
1068         }
1069
1070         /* Adjust if canonical order is different from natural order */
1071         if(specs->from_canonical_order)
1072                 value = specs->from_canonical_order[value];
1073
1074         /* Set presence to be able to free it later */
1075         _set_present_idx(st, specs->pres_offset, specs->pres_size, value + 1);
1076
1077         elm = &td->elements[value];
1078         if(elm->flags & ATF_POINTER) {
1079                 /* Member is a pointer to another structure */
1080                 memb_ptr2 = (void **)((char *)st + elm->memb_offset);
1081         } else {
1082                 memb_ptr = (char *)st + elm->memb_offset;
1083                 memb_ptr2 = &memb_ptr;
1084         }
1085         ASN_DEBUG("Discovered CHOICE %s encodes %s", td->name, elm->name);
1086
1087         if(ct && ct->range_bits >= 0) {
1088                 rv = elm->type->op->aper_decoder(opt_codec_ctx, elm->type,
1089                                                  elm->encoding_constraints.per_constraints, memb_ptr2, pd);
1090         } else {
1091                 rv = aper_open_type_get(opt_codec_ctx, elm->type,
1092                                         elm->encoding_constraints.per_constraints, memb_ptr2, pd);
1093         }
1094
1095         if(rv.code != RC_OK)
1096                 ASN_DEBUG("Failed to decode %s in %s (CHOICE) %d",
1097                           elm->name, td->name, rv.code);
1098         return rv;
1099 }
1100
1101 asn_enc_rval_t
1102 CHOICE_encode_aper(const asn_TYPE_descriptor_t *td,
1103                    const asn_per_constraints_t *constraints,
1104                    const void *sptr, asn_per_outp_t *po) {
1105         const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
1106         const asn_TYPE_member_t *elm; /* CHOICE's element */
1107         const asn_per_constraint_t *ct = NULL;
1108         const asn_per_constraint_t *ext_ct = NULL;
1109         const void *memb_ptr;
1110         unsigned present;
1111         int present_enc;
1112
1113         if(!sptr) ASN__ENCODE_FAILED;
1114
1115         ASN_DEBUG("Encoding %s as CHOICE using ALIGNED PER", td->name);
1116
1117         if(constraints) ct = &constraints->value;
1118         else if(td->encoding_constraints.per_constraints)
1119                 ct = &td->encoding_constraints.per_constraints->value;
1120         else ct = NULL;
1121
1122         present = _fetch_present_idx(sptr,
1123                                      specs->pres_offset, specs->pres_size);
1124
1125         /*
1126          * If the structure was not initialized properly, it cannot be encoded:
1127          * can't deduce what to encode in the choice type.
1128          */
1129         if(present <= 0 || (unsigned)present > td->elements_count)
1130                 ASN__ENCODE_FAILED;
1131         else
1132                 present--;
1133
1134         /* Adjust if canonical order is different from natural order */
1135         if(specs->to_canonical_order)
1136                 present_enc = specs->to_canonical_order[present];
1137         else
1138                 present_enc = present;
1139
1140         ASN_DEBUG("Encoding %s CHOICE element %d", td->name, present);
1141
1142         if(ct && (ct->range_bits >= 0)) {
1143           // Value is not within the range of the primary values ?
1144           if(present < ct->lower_bound || present > ct->upper_bound) {
1145             if(ct->flags & APC_EXTENSIBLE) {
1146               ASN_DEBUG("CHOICE member %d (enc %d) is an extension (%ld..%ld)",
1147                         present, present_enc, ct->lower_bound, ct->upper_bound);
1148               // X691/23.5 Extension marker = 1
1149               if(per_put_few_bits(po, 1, 1)) {
1150                 ASN__ENCODE_FAILED;
1151               }
1152             } else {
1153               ASN__ENCODE_FAILED;
1154             }
1155             // no more need of constraint.
1156             ext_ct = ct;
1157             ct = NULL;
1158           }
1159         }
1160
1161         if(ct && (ct->flags & APC_EXTENSIBLE)) {
1162           ASN_DEBUG("CHOICE member %d (enc %d) is not an extension (%ld..%ld)",
1163                     present, present, ct->lower_bound, ct->upper_bound);
1164           // X691.23.5 Extension marker = 0
1165           if(per_put_few_bits(po, 0, 1)) {
1166             ASN__ENCODE_FAILED;
1167           }
1168         }
1169
1170         elm = &td->elements[present];
1171         if(elm->flags & ATF_POINTER) {
1172                 /* Member is a pointer to another structure */
1173                 memb_ptr = *(const void *const *)((const char *)sptr + elm->memb_offset);
1174                 if(!memb_ptr) ASN__ENCODE_FAILED;
1175         } else {
1176                 memb_ptr = (const char *)sptr + elm->memb_offset;
1177         }
1178
1179         if(ct && (ct->range_bits >= 0)) {
1180                 // By construction (ct != 0), the alternative value is a non extended one.
1181                 // X691/23.7 X691/23.6 alternative value encoded as a range_bits bits value.
1182                 if(per_put_few_bits(po, present_enc, ct->range_bits))
1183                         ASN__ENCODE_FAILED;
1184
1185                 return elm->type->op->aper_encoder(elm->type, elm->encoding_constraints.per_constraints,
1186                                                    memb_ptr, po);
1187         } else {
1188                 asn_enc_rval_t rval = {0,0,0};
1189                 if(specs->ext_start == -1)
1190                         ASN__ENCODE_FAILED;
1191                 // X691/23.8 normally encoded as a small non negative whole number
1192
1193                 if(ext_ct && aper_put_nsnnwn(po, ext_ct->range_bits, present_enc - specs->ext_start))
1194                         ASN__ENCODE_FAILED;
1195                 if(aper_open_type_put(elm->type, elm->encoding_constraints.per_constraints,
1196                                       memb_ptr, po))
1197                         ASN__ENCODE_FAILED;
1198                 rval.encoded = 0;
1199                 ASN__ENCODED_OK(rval);
1200         }
1201 }
1202
1203 int
1204 CHOICE_print(const asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
1205              asn_app_consume_bytes_f *cb, void *app_key) {
1206     const asn_CHOICE_specifics_t *specs = (const asn_CHOICE_specifics_t *)td->specifics;
1207         unsigned present;
1208
1209         if(!sptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
1210
1211         /*
1212          * Figure out which CHOICE element is encoded.
1213          */
1214         present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);
1215
1216         /*
1217          * Print that element.
1218          */
1219         if(present > 0 && present <= td->elements_count) {
1220                 asn_TYPE_member_t *elm = &td->elements[present-1];
1221                 const void *memb_ptr;
1222
1223                 if(elm->flags & ATF_POINTER) {
1224                         memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
1225                         if(!memb_ptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
1226                 } else {
1227                         memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
1228                 }
1229
1230                 /* Print member's name and stuff */
1231                 if(0) {
1232                         if(cb(elm->name, strlen(elm->name), app_key) < 0
1233                         || cb(": ", 2, app_key) < 0)
1234                                 return -1;
1235                 }
1236
1237                 return elm->type->op->print_struct(elm->type, memb_ptr, ilevel,
1238                         cb, app_key);
1239         } else {
1240                 return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
1241         }
1242 }
1243
1244 void
1245 CHOICE_free(const asn_TYPE_descriptor_t *td, void *ptr,
1246             enum asn_struct_free_method method) {
1247     const asn_CHOICE_specifics_t *specs =
1248         (const asn_CHOICE_specifics_t *)td->specifics;
1249     unsigned present;
1250
1251         if(!td || !ptr)
1252                 return;
1253
1254         ASN_DEBUG("Freeing %s as CHOICE", td->name);
1255
1256         /*
1257          * Figure out which CHOICE element is encoded.
1258          */
1259         present = _fetch_present_idx(ptr, specs->pres_offset, specs->pres_size);
1260
1261         /*
1262          * Free that element.
1263          */
1264         if(present > 0 && present <= td->elements_count) {
1265                 asn_TYPE_member_t *elm = &td->elements[present-1];
1266                 void *memb_ptr;
1267
1268                 if(elm->flags & ATF_POINTER) {
1269                         memb_ptr = *(void **)((char *)ptr + elm->memb_offset);
1270                         if(memb_ptr)
1271                                 ASN_STRUCT_FREE(*elm->type, memb_ptr);
1272                 } else {
1273                         memb_ptr = (void *)((char *)ptr + elm->memb_offset);
1274                         ASN_STRUCT_FREE_CONTENTS_ONLY(*elm->type, memb_ptr);
1275                 }
1276         }
1277
1278     switch(method) {
1279     case ASFM_FREE_EVERYTHING:
1280         FREEMEM(ptr);
1281         break;
1282     case ASFM_FREE_UNDERLYING:
1283         break;
1284     case ASFM_FREE_UNDERLYING_AND_RESET:
1285         memset(ptr, 0, specs->struct_size);
1286         break;
1287     }
1288 }
1289
1290
1291 /*
1292  * The following functions functions offer protection against -fshort-enums,
1293  * compatible with little- and big-endian machines.
1294  * If assertion is triggered, either disable -fshort-enums, or add an entry
1295  * here with the ->pres_size of your target stracture.
1296  * Unless the target structure is packed, the ".present" member
1297  * is guaranteed to be aligned properly. ASN.1 compiler itself does not
1298  * produce packed code.
1299  */
1300 static unsigned
1301 _fetch_present_idx(const void *struct_ptr, unsigned pres_offset,
1302                    unsigned pres_size) {
1303     const void *present_ptr;
1304         unsigned present;
1305
1306         present_ptr = ((const char *)struct_ptr) + pres_offset;
1307
1308         switch(pres_size) {
1309         case sizeof(int):       present = *(const unsigned int *)present_ptr; break;
1310         case sizeof(short):     present = *(const unsigned short *)present_ptr; break;
1311         case sizeof(char):      present = *(const unsigned char *)present_ptr; break;
1312         default:
1313                 /* ANSI C mandates enum to be equivalent to integer */
1314                 assert(pres_size != sizeof(int));
1315                 return 0;       /* If not aborted, pass back safe value */
1316         }
1317
1318         return present;
1319 }
1320
1321 static void
1322 _set_present_idx(void *struct_ptr, unsigned pres_offset, unsigned pres_size,
1323                  unsigned present) {
1324     void *present_ptr;
1325         present_ptr = ((char *)struct_ptr) + pres_offset;
1326
1327         switch(pres_size) {
1328         case sizeof(int):       *(unsigned int *)present_ptr   = present; break;
1329         case sizeof(short):     *(unsigned short *)present_ptr = present; break;
1330         case sizeof(char):      *(unsigned char *)present_ptr  = present; break;
1331         default:
1332                 /* ANSI C mandates enum to be equivalent to integer */
1333                 assert(pres_size != sizeof(int));
1334         }
1335 }
1336
1337 static const void *
1338 _get_member_ptr(const asn_TYPE_descriptor_t *td, const void *sptr,
1339                 asn_TYPE_member_t **elm_ptr, unsigned *present_out) {
1340     const asn_CHOICE_specifics_t *specs =
1341         (const asn_CHOICE_specifics_t *)td->specifics;
1342     unsigned present;
1343
1344     if(!sptr) {
1345         *elm_ptr = NULL;
1346         *present_out = 0;
1347         return NULL;
1348     }
1349
1350     /*
1351          * Figure out which CHOICE element is encoded.
1352          */
1353         present = _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
1354     *present_out = present;
1355
1356     /*
1357      * The presence index is intentionally 1-based to avoid
1358      * treating zeroed structure as a valid one.
1359      */
1360         if(present > 0 && present <= td->elements_count) {
1361         asn_TYPE_member_t *const elm = &td->elements[present - 1];
1362         const void *memb_ptr;
1363
1364                 if(elm->flags & ATF_POINTER) {
1365             memb_ptr =
1366                 *(const void *const *)((const char *)sptr + elm->memb_offset);
1367         } else {
1368             memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
1369         }
1370         *elm_ptr = elm;
1371         return memb_ptr;
1372     } else {
1373         *elm_ptr = NULL;
1374         return NULL;
1375     }
1376
1377 }
1378
1379 int
1380 CHOICE_compare(const asn_TYPE_descriptor_t *td, const void *aptr, const void *bptr) {
1381     asn_TYPE_member_t *aelm;
1382     asn_TYPE_member_t *belm;
1383     unsigned apresent = 0;
1384     unsigned bpresent = 0;
1385     const void *amember = _get_member_ptr(td, aptr, &aelm, &apresent);
1386     const void *bmember = _get_member_ptr(td, bptr, &belm, &bpresent);
1387
1388     if(amember && bmember) {
1389         if(apresent == bpresent) {
1390             assert(aelm == belm);
1391             return aelm->type->op->compare_struct(aelm->type, amember, bmember);
1392         } else if(apresent < bpresent) {
1393             return -1;
1394         } else {
1395             return 1;
1396         }
1397     } else if(!amember) {
1398         return -1;
1399     } else {
1400         return 1;
1401     }
1402 }
1403
1404 /*
1405  * Return the 1-based choice variant presence index.
1406  * Returns 0 in case of error.
1407  */
1408 unsigned
1409 CHOICE_variant_get_presence(const asn_TYPE_descriptor_t *td, const void *sptr) {
1410     const asn_CHOICE_specifics_t *specs =
1411         (const asn_CHOICE_specifics_t *)td->specifics;
1412     return _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
1413 }
1414
1415 /*
1416  * Sets or resets the 1-based choice variant presence index.
1417  * In case a previous index is not zero, the currently selected structure
1418  * member is freed and zeroed-out first.
1419  * Returns 0 on success and -1 on error.
1420  */
1421 int
1422 CHOICE_variant_set_presence(const asn_TYPE_descriptor_t *td, void *sptr,
1423                             unsigned present) {
1424     const asn_CHOICE_specifics_t *specs =
1425         (const asn_CHOICE_specifics_t *)td->specifics;
1426     unsigned old_present;
1427
1428     if(!sptr) {
1429         return -1;
1430     }
1431
1432     if(present > td->elements_count)
1433         return -1;
1434
1435     old_present =
1436         _fetch_present_idx(sptr, specs->pres_offset, specs->pres_size);
1437     if(present == old_present)
1438         return 0;
1439
1440     if(old_present != 0) {
1441         assert(old_present <= td->elements_count);
1442         ASN_STRUCT_RESET(*td, sptr);
1443     }
1444
1445     _set_present_idx(sptr, specs->pres_offset, specs->pres_size, present);
1446
1447     return 0;
1448 }
1449
1450
1451 asn_random_fill_result_t
1452 CHOICE_random_fill(const asn_TYPE_descriptor_t *td, void **sptr,
1453                    const asn_encoding_constraints_t *constr,
1454                    size_t max_length) {
1455     const asn_CHOICE_specifics_t *specs =
1456         (const asn_CHOICE_specifics_t *)td->specifics;
1457     asn_random_fill_result_t res;
1458     asn_random_fill_result_t result_failed = {ARFILL_FAILED, 0};
1459     asn_random_fill_result_t result_skipped = {ARFILL_SKIPPED, 0};
1460     const asn_TYPE_member_t *elm;
1461     unsigned present;
1462     void *memb_ptr;   /* Pointer to the member */
1463     void **memb_ptr2; /* Pointer to that pointer */
1464     void *st = *sptr;
1465
1466     if(max_length == 0) return result_skipped;
1467
1468     (void)constr;
1469
1470     if(st == NULL) {
1471         st = CALLOC(1, specs->struct_size);
1472         if(st == NULL) {
1473             return result_failed;
1474         }
1475     }
1476
1477     present = asn_random_between(1, td->elements_count);
1478     elm = &td->elements[present - 1];
1479
1480         if(elm->flags & ATF_POINTER) {
1481                 /* Member is a pointer to another structure */
1482                 memb_ptr2 = (void **)((char *)st + elm->memb_offset);
1483         } else {
1484                 memb_ptr = (char *)st + elm->memb_offset;
1485                 memb_ptr2 = &memb_ptr;
1486         }
1487
1488     res = elm->type->op->random_fill(elm->type, memb_ptr2,
1489                                     &elm->encoding_constraints, max_length);
1490     _set_present_idx(st, specs->pres_offset, specs->pres_size, present);
1491     if(res.code == ARFILL_OK) {
1492         *sptr = st;
1493     } else {
1494         if(st == *sptr) {
1495             ASN_STRUCT_RESET(*td, st);
1496         } else {
1497             ASN_STRUCT_FREE(*td, st);
1498         }
1499     }
1500
1501     return res;
1502 }
1503
1504
1505 asn_TYPE_operation_t asn_OP_CHOICE = {
1506         CHOICE_free,
1507         CHOICE_print,
1508         CHOICE_compare,
1509         CHOICE_decode_ber,
1510         CHOICE_encode_der,
1511         CHOICE_decode_xer,
1512         CHOICE_encode_xer,
1513 #ifdef  ASN_DISABLE_OER_SUPPORT
1514         0,
1515         0,
1516 #else
1517         CHOICE_decode_oer,
1518         CHOICE_encode_oer,
1519 #endif  /* ASN_DISABLE_OER_SUPPORT */
1520 #ifdef ASN_DISABLE_PER_SUPPORT
1521         0,
1522         0,
1523         0,
1524         0,
1525 #else
1526         CHOICE_decode_uper,
1527         CHOICE_encode_uper,
1528         CHOICE_decode_aper,
1529         CHOICE_encode_aper,
1530 #endif  /* ASN_DISABLE_PER_SUPPORT */
1531         CHOICE_random_fill,
1532         CHOICE_outmost_tag
1533 };