contrib/hstore/hstore_gist.c

   1 /*
   2  * $PostgreSQL$
   3  */
   4 #include "postgres.h"
   5
   6 #include "access/gist.h"
   7 #include "access/itup.h"
   8 #include "access/skey.h"
   9 #include "crc32.h"
  10
  11 #include "hstore.h"
  12
  13 /* bigint defines */
  14 #define BITBYTE 8
  15 #define SIGLENINT  4                    /* >122 => key will toast, so very slow!!! */
  16 #define SIGLEN  ( sizeof(int)*SIGLENINT )
  17 #define SIGLENBIT (SIGLEN*BITBYTE)
  18
  19 typedef char BITVEC[SIGLEN];
  20 typedef char *BITVECP;
  21
  22 #define SIGPTR(x)  ( (BITVECP) ARR_DATA_PTR(x) )
  23
  24
  25 #define LOOPBYTE \
  26                         for(i=0;i<SIGLEN;i++)
  27
  28 #define LOOPBIT \
  29                         for(i=0;i<SIGLENBIT;i++)
  30
  31 /* beware of multiple evaluation of arguments to these macros! */
  32 #define GETBYTE(x,i) ( *( (BITVECP)(x) + (int)( (i) / BITBYTE ) ) )
  33 #define GETBITBYTE(x,i) ( (*((char*)(x)) >> (i)) & 0x01 )
  34 #define CLRBIT(x,i)   GETBYTE(x,i) &= ~( 0x01 << ( (i) % BITBYTE ) )
  35 #define SETBIT(x,i)   GETBYTE(x,i) |=  ( 0x01 << ( (i) % BITBYTE ) )
  36 #define GETBIT(x,i) ( (GETBYTE(x,i) >> ( (i) % BITBYTE )) & 0x01 )
  37 #define HASHVAL(val) (((unsigned int)(val)) % SIGLENBIT)
  38 #define HASH(sign, val) SETBIT((sign), HASHVAL(val))
  39
  40 typedef struct
  41 {
  42         int32           vl_len_;                /* varlena header (do not touch directly!) */
  43         int4            flag;
  44         char            data[1];
  45 }       GISTTYPE;
  46
  47 #define ALLISTRUE               0x04
  48
  49 #define ISALLTRUE(x)    ( ((GISTTYPE*)x)->flag & ALLISTRUE )
  50
  51 #define GTHDRSIZE               (VARHDRSZ + sizeof(int4))
  52 #define CALCGTSIZE(flag) ( GTHDRSIZE+(((flag) & ALLISTRUE) ? 0 : SIGLEN) )
  53
  54 #define GETSIGN(x)              ( (BITVECP)( (char*)x+GTHDRSIZE ) )
  55
  56 #define SUMBIT(val) (           \
  57         GETBITBYTE((val),0) + \
  58         GETBITBYTE((val),1) + \
  59         GETBITBYTE((val),2) + \
  60         GETBITBYTE((val),3) + \
  61         GETBITBYTE((val),4) + \
  62         GETBITBYTE((val),5) + \
  63         GETBITBYTE((val),6) + \
  64         GETBITBYTE((val),7)   \
  65 )
  66
  67 #define GETENTRY(vec,pos) ((GISTTYPE *) DatumGetPointer((vec)->vector[(pos)].key))
  68
  69 #define WISH_F(a,b,c) (double)( -(double)(((a)-(b))*((a)-(b))*((a)-(b)))*(c) )
  70
  71 PG_FUNCTION_INFO_V1(ghstore_in);
  72 Datum           ghstore_in(PG_FUNCTION_ARGS);
  73
  74 PG_FUNCTION_INFO_V1(ghstore_out);
  75 Datum           ghstore_out(PG_FUNCTION_ARGS);
  76
  77
  78 Datum
  79 ghstore_in(PG_FUNCTION_ARGS)
  80 {
  81         elog(ERROR, "Not implemented");
  82         PG_RETURN_DATUM(0);
  83 }
  84
  85 Datum
  86 ghstore_out(PG_FUNCTION_ARGS)
  87 {
  88         elog(ERROR, "Not implemented");
  89         PG_RETURN_DATUM(0);
  90 }
  91
  92 PG_FUNCTION_INFO_V1(ghstore_consistent);
  93 PG_FUNCTION_INFO_V1(ghstore_compress);
  94 PG_FUNCTION_INFO_V1(ghstore_decompress);
  95 PG_FUNCTION_INFO_V1(ghstore_penalty);
  96 PG_FUNCTION_INFO_V1(ghstore_picksplit);
  97 PG_FUNCTION_INFO_V1(ghstore_union);
  98 PG_FUNCTION_INFO_V1(ghstore_same);
  99
 100 Datum           ghstore_consistent(PG_FUNCTION_ARGS);
 101 Datum           ghstore_compress(PG_FUNCTION_ARGS);
 102 Datum           ghstore_decompress(PG_FUNCTION_ARGS);
 103 Datum           ghstore_penalty(PG_FUNCTION_ARGS);
 104 Datum           ghstore_picksplit(PG_FUNCTION_ARGS);
 105 Datum           ghstore_union(PG_FUNCTION_ARGS);
 106 Datum           ghstore_same(PG_FUNCTION_ARGS);
 107
 108 Datum
 109 ghstore_compress(PG_FUNCTION_ARGS)
 110 {
 111         GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
 112         GISTENTRY  *retval = entry;
 113
 114         if (entry->leafkey)
 115         {
 116                 GISTTYPE   *res = (GISTTYPE *) palloc0(CALCGTSIZE(0));
 117                 HStore     *toastedval = (HStore *) DatumGetPointer(entry->key);
 118                 HStore     *val = (HStore *) DatumGetPointer(PG_DETOAST_DATUM(entry->key));
 119                 HEntry     *ptr = ARRPTR(val);
 120                 char       *words = STRPTR(val);
 121
 122                 SET_VARSIZE(res, CALCGTSIZE(0));
 123
 124                 while (ptr - ARRPTR(val) < val->size)
 125                 {
 126                         int                     h;
 127
 128                         h = crc32_sz((char *) (words + ptr->pos), ptr->keylen);
 129                         HASH(GETSIGN(res), h);
 130                         if (!ptr->valisnull)
 131                         {
 132                                 h = crc32_sz((char *) (words + ptr->pos + ptr->keylen), ptr->vallen);
 133                                 HASH(GETSIGN(res), h);
 134                         }
 135                         ptr++;
 136                 }
 137
 138                 if (val != toastedval)
 139                         pfree(val);
 140
 141                 retval = (GISTENTRY *) palloc(sizeof(GISTENTRY));
 142                 gistentryinit(*retval, PointerGetDatum(res),
 143                                           entry->rel, entry->page,
 144                                           entry->offset,
 145                                           FALSE);
 146         }
 147         else if (!ISALLTRUE(DatumGetPointer(entry->key)))
 148         {
 149                 int4            i;
 150                 GISTTYPE   *res;
 151                 BITVECP         sign = GETSIGN(DatumGetPointer(entry->key));
 152
 153                 LOOPBYTE
 154                 {
 155                         if ((sign[i] & 0xff) != 0xff)
 156                                 PG_RETURN_POINTER(retval);
 157                 }
 158
 159                 res = (GISTTYPE *) palloc(CALCGTSIZE(ALLISTRUE));
 160                 SET_VARSIZE(res, CALCGTSIZE(ALLISTRUE));
 161                 res->flag = ALLISTRUE;
 162
 163                 retval = (GISTENTRY *) palloc(sizeof(GISTENTRY));
 164                 gistentryinit(*retval, PointerGetDatum(res),
 165                                           entry->rel, entry->page,
 166                                           entry->offset,
 167                                           FALSE);
 168         }
 169
 170         PG_RETURN_POINTER(retval);
 171 }
 172
 173 Datum
 174 ghstore_decompress(PG_FUNCTION_ARGS)
 175 {
 176         GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
 177         GISTENTRY  *retval;
 178         HStore     *key;
 179
 180         key = (HStore *) PG_DETOAST_DATUM(entry->key);
 181
 182         if (key != (HStore *) DatumGetPointer(entry->key))
 183         {
 184                 /* need to pass back the decompressed item */
 185                 retval = palloc(sizeof(GISTENTRY));
 186                 gistentryinit(*retval, PointerGetDatum(key),
 187                                           entry->rel, entry->page, entry->offset, entry->leafkey);
 188                 PG_RETURN_POINTER(retval);
 189         }
 190         else
 191         {
 192                 /* we can return the entry as-is */
 193                 PG_RETURN_POINTER(entry);
 194         }
 195 }
 196
 197 Datum
 198 ghstore_same(PG_FUNCTION_ARGS)
 199 {
 200         GISTTYPE   *a = (GISTTYPE *) PG_GETARG_POINTER(0);
 201         GISTTYPE   *b = (GISTTYPE *) PG_GETARG_POINTER(1);
 202         bool       *result = (bool *) PG_GETARG_POINTER(2);
 203
 204         if (ISALLTRUE(a) && ISALLTRUE(b))
 205                 *result = true;
 206         else if (ISALLTRUE(a))
 207                 *result = false;
 208         else if (ISALLTRUE(b))
 209                 *result = false;
 210         else
 211         {
 212                 int4            i;
 213                 BITVECP         sa = GETSIGN(a),
 214                                         sb = GETSIGN(b);
 215
 216                 *result = true;
 217                 LOOPBYTE
 218                 {
 219                         if (sa[i] != sb[i])
 220                         {
 221                                 *result = false;
 222                                 break;
 223                         }
 224                 }
 225         }
 226         PG_RETURN_POINTER(result);
 227 }
 228
 229 static int4
 230 sizebitvec(BITVECP sign)
 231 {
 232         int4            size = 0,
 233                                 i;
 234
 235         LOOPBYTE
 236         {
 237                 size += SUMBIT(sign);
 238                 sign = (BITVECP) (((char *) sign) + 1);
 239         }
 240         return size;
 241 }
 242
 243 static int
 244 hemdistsign(BITVECP a, BITVECP b)
 245 {
 246         int                     i,
 247                                 dist = 0;
 248
 249         LOOPBIT
 250         {
 251                 if (GETBIT(a, i) != GETBIT(b, i))
 252                         dist++;
 253         }
 254         return dist;
 255 }
 256
 257 static int
 258 hemdist(GISTTYPE * a, GISTTYPE * b)
 259 {
 260         if (ISALLTRUE(a))
 261         {
 262                 if (ISALLTRUE(b))
 263                         return 0;
 264                 else
 265                         return SIGLENBIT - sizebitvec(GETSIGN(b));
 266         }
 267         else if (ISALLTRUE(b))
 268                 return SIGLENBIT - sizebitvec(GETSIGN(a));
 269
 270         return hemdistsign(GETSIGN(a), GETSIGN(b));
 271 }
 272
 273 static int4
 274 unionkey(BITVECP sbase, GISTTYPE * add)
 275 {
 276         int4            i;
 277         BITVECP         sadd = GETSIGN(add);
 278
 279         if (ISALLTRUE(add))
 280                 return 1;
 281         LOOPBYTE
 282                 sbase[i] |= sadd[i];
 283         return 0;
 284 }
 285
 286 Datum
 287 ghstore_union(PG_FUNCTION_ARGS)
 288 {
 289         GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
 290         int4            len = entryvec->n;
 291
 292         int                *size = (int *) PG_GETARG_POINTER(1);
 293         BITVEC          base;
 294         int4            i;
 295         int4            flag = 0;
 296         GISTTYPE   *result;
 297
 298         MemSet((void *) base, 0, sizeof(BITVEC));
 299         for (i = 0; i < len; i++)
 300         {
 301                 if (unionkey(base, GETENTRY(entryvec, i)))
 302                 {
 303                         flag = ALLISTRUE;
 304                         break;
 305                 }
 306         }
 307
 308         len = CALCGTSIZE(flag);
 309         result = (GISTTYPE *) palloc(len);
 310         SET_VARSIZE(result, len);
 311         result->flag = flag;
 312         if (!ISALLTRUE(result))
 313                 memcpy((void *) GETSIGN(result), (void *) base, sizeof(BITVEC));
 314         *size = len;
 315
 316         PG_RETURN_POINTER(result);
 317 }
 318
 319 Datum
 320 ghstore_penalty(PG_FUNCTION_ARGS)
 321 {
 322         GISTENTRY  *origentry = (GISTENTRY *) PG_GETARG_POINTER(0); /* always ISSIGNKEY */
 323         GISTENTRY  *newentry = (GISTENTRY *) PG_GETARG_POINTER(1);
 324         float      *penalty = (float *) PG_GETARG_POINTER(2);
 325         GISTTYPE   *origval = (GISTTYPE *) DatumGetPointer(origentry->key);
 326         GISTTYPE   *newval = (GISTTYPE *) DatumGetPointer(newentry->key);
 327
 328         *penalty = hemdist(origval, newval);
 329         PG_RETURN_POINTER(penalty);
 330 }
 331
 332
 333 typedef struct
 334 {
 335         OffsetNumber pos;
 336         int4            cost;
 337 } SPLITCOST;
 338
 339 static int
 340 comparecost(const void *a, const void *b)
 341 {
 342         return ((SPLITCOST *) a)->cost - ((SPLITCOST *) b)->cost;
 343 }
 344
 345
 346 Datum
 347 ghstore_picksplit(PG_FUNCTION_ARGS)
 348 {
 349         GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
 350         OffsetNumber maxoff = entryvec->n - 2;
 351
 352         GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
 353         OffsetNumber k,
 354                                 j;
 355         GISTTYPE   *datum_l,
 356                            *datum_r;
 357         BITVECP         union_l,
 358                                 union_r;
 359         int4            size_alpha,
 360                                 size_beta;
 361         int4            size_waste,
 362                                 waste = -1;
 363         int4            nbytes;
 364         OffsetNumber seed_1 = 0,
 365                                 seed_2 = 0;
 366         OffsetNumber *left,
 367                            *right;
 368         BITVECP         ptr;
 369         int                     i;
 370         SPLITCOST  *costvector;
 371         GISTTYPE   *_k,
 372                            *_j;
 373
 374         nbytes = (maxoff + 2) * sizeof(OffsetNumber);
 375         v->spl_left = (OffsetNumber *) palloc(nbytes);
 376         v->spl_right = (OffsetNumber *) palloc(nbytes);
 377
 378         for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k))
 379         {
 380                 _k = GETENTRY(entryvec, k);
 381                 for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j))
 382                 {
 383                         size_waste = hemdist(_k, GETENTRY(entryvec, j));
 384                         if (size_waste > waste)
 385                         {
 386                                 waste = size_waste;
 387                                 seed_1 = k;
 388                                 seed_2 = j;
 389                         }
 390                 }
 391         }
 392
 393         left = v->spl_left;
 394         v->spl_nleft = 0;
 395         right = v->spl_right;
 396         v->spl_nright = 0;
 397
 398         if (seed_1 == 0 || seed_2 == 0)
 399         {
 400                 seed_1 = 1;
 401                 seed_2 = 2;
 402         }
 403
 404         /* form initial .. */
 405         if (ISALLTRUE(GETENTRY(entryvec, seed_1)))
 406         {
 407                 datum_l = (GISTTYPE *) palloc(GTHDRSIZE);
 408                 SET_VARSIZE(datum_l, GTHDRSIZE);
 409                 datum_l->flag = ALLISTRUE;
 410         }
 411         else
 412         {
 413                 datum_l = (GISTTYPE *) palloc(GTHDRSIZE + SIGLEN);
 414                 SET_VARSIZE(datum_l, GTHDRSIZE + SIGLEN);
 415                 datum_l->flag = 0;
 416                 memcpy((void *) GETSIGN(datum_l), (void *) GETSIGN(GETENTRY(entryvec, seed_1)), sizeof(BITVEC))
 417                         ;
 418         }
 419         if (ISALLTRUE(GETENTRY(entryvec, seed_2)))
 420         {
 421                 datum_r = (GISTTYPE *) palloc(GTHDRSIZE);
 422                 SET_VARSIZE(datum_r, GTHDRSIZE);
 423                 datum_r->flag = ALLISTRUE;
 424         }
 425         else
 426         {
 427                 datum_r = (GISTTYPE *) palloc(GTHDRSIZE + SIGLEN);
 428                 SET_VARSIZE(datum_r, GTHDRSIZE + SIGLEN);
 429                 datum_r->flag = 0;
 430                 memcpy((void *) GETSIGN(datum_r), (void *) GETSIGN(GETENTRY(entryvec, seed_2)), sizeof(BITVEC));
 431         }
 432
 433         maxoff = OffsetNumberNext(maxoff);
 434         /* sort before ... */
 435         costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
 436         for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j))
 437         {
 438                 costvector[j - 1].pos = j;
 439                 _j = GETENTRY(entryvec, j);
 440                 size_alpha = hemdist(datum_l, _j);
 441                 size_beta = hemdist(datum_r, _j);
 442                 costvector[j - 1].cost = abs(size_alpha - size_beta);
 443         }
 444         qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
 445
 446         union_l = GETSIGN(datum_l);
 447         union_r = GETSIGN(datum_r);
 448
 449         for (k = 0; k < maxoff; k++)
 450         {
 451                 j = costvector[k].pos;
 452                 if (j == seed_1)
 453                 {
 454                         *left++ = j;
 455                         v->spl_nleft++;
 456                         continue;
 457                 }
 458                 else if (j == seed_2)
 459                 {
 460                         *right++ = j;
 461                         v->spl_nright++;
 462                         continue;
 463                 }
 464                 _j = GETENTRY(entryvec, j);
 465                 size_alpha = hemdist(datum_l, _j);
 466                 size_beta = hemdist(datum_r, _j);
 467
 468                 if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.0001))
 469                 {
 470                         if (ISALLTRUE(datum_l) || ISALLTRUE(_j))
 471                         {
 472                                 if (!ISALLTRUE(datum_l))
 473                                         MemSet((void *) union_l, 0xff, sizeof(BITVEC));
 474                         }
 475                         else
 476                         {
 477                                 ptr = GETSIGN(_j);
 478                                 LOOPBYTE
 479                                         union_l[i] |= ptr[i];
 480                         }
 481                         *left++ = j;
 482                         v->spl_nleft++;
 483                 }
 484                 else
 485                 {
 486                         if (ISALLTRUE(datum_r) || ISALLTRUE(_j))
 487                         {
 488                                 if (!ISALLTRUE(datum_r))
 489                                         MemSet((void *) union_r, 0xff, sizeof(BITVEC));
 490                         }
 491                         else
 492                         {
 493                                 ptr = GETSIGN(_j);
 494                                 LOOPBYTE
 495                                         union_r[i] |= ptr[i];
 496                         }
 497                         *right++ = j;
 498                         v->spl_nright++;
 499                 }
 500         }
 501
 502         *right = *left = FirstOffsetNumber;
 503         pfree(costvector);
 504
 505         v->spl_ldatum = PointerGetDatum(datum_l);
 506         v->spl_rdatum = PointerGetDatum(datum_r);
 507
 508         PG_RETURN_POINTER(v);
 509 }
 510
 511
 512 Datum
 513 ghstore_consistent(PG_FUNCTION_ARGS)
 514 {
 515         GISTTYPE   *entry = (GISTTYPE *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
 516         StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
 517         /* Oid          subtype = PG_GETARG_OID(3); */
 518         bool       *recheck = (bool *) PG_GETARG_POINTER(4);
 519         bool            res = true;
 520         BITVECP         sign;
 521
 522         /* All cases served by this function are inexact */
 523         *recheck = true;
 524
 525         if (ISALLTRUE(entry))
 526                 PG_RETURN_BOOL(true);
 527
 528         sign = GETSIGN(entry);
 529
 530         if (strategy == HStoreContainsStrategyNumber || strategy == 13 /* hack for old strats */ )
 531         {
 532                 HStore     *query = PG_GETARG_HS(1);
 533                 HEntry     *qe = ARRPTR(query);
 534                 char       *qv = STRPTR(query);
 535
 536                 while (res && qe - ARRPTR(query) < query->size)
 537                 {
 538                         int                     crc = crc32_sz((char *) (qv + qe->pos), qe->keylen);
 539
 540                         if (GETBIT(sign, HASHVAL(crc)))
 541                         {
 542                                 if (!qe->valisnull)
 543                                 {
 544                                         crc = crc32_sz((char *) (qv + qe->pos + qe->keylen), qe->vallen);
 545                                         if (!GETBIT(sign, HASHVAL(crc)))
 546                                                 res = false;
 547                                 }
 548                         }
 549                         else
 550                                 res = false;
 551                         qe++;
 552                 }
 553         }
 554         else if (strategy == HStoreExistsStrategyNumber)
 555         {
 556                 text       *query = PG_GETARG_TEXT_P(1);
 557                 int                     crc = crc32_sz(VARDATA(query), VARSIZE(query) - VARHDRSZ);
 558
 559                 res = (GETBIT(sign, HASHVAL(crc))) ? true : false;
 560         }
 561         else
 562                 elog(ERROR, "Unsupported strategy number: %d", strategy);
 563
 564         PG_RETURN_BOOL(res);
 565 }