git.sur5r.net Git - openldap/blob - servers/slapd/back-ldbm/idl.c

   1 /* idl.c - ldap id list handling routines */
   2 /* $OpenLDAP$ */
   3 /*
   4  * Copyright 1998-2000 The OpenLDAP Foundation, All Rights Reserved.
   5  * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
   6  */
   7
   8 #include "portable.h"
   9
  10 #include <stdio.h>
  11
  12 #include <ac/string.h>
  13 #include <ac/socket.h>
  14
  15 #include "slap.h"
  16 #include "back-ldbm.h"
  17
  18 static ID_BLOCK* idl_dup( ID_BLOCK *idl );
  19
  20 static void cont_alloc( Datum *cont, Datum *key )
  21 {
  22         ldbm_datum_init( *cont );
  23         cont->dsize = 1 + sizeof(ID) + key->dsize;
  24         cont->dptr = ch_malloc( cont->dsize );
  25
  26         * (unsigned char *) cont->dptr = SLAP_INDEX_CONT_PREFIX;
  27
  28         AC_MEMCPY( &((unsigned char *)cont->dptr)[1 + sizeof(ID)],
  29                 key->dptr, key->dsize );
  30 }
  31
  32 static void cont_id( Datum *cont, ID id )
  33 {
  34         int i;
  35
  36         for( i=1; i <= sizeof(id); i++) {
  37                 ((unsigned char *)cont->dptr)[i] = (unsigned char)(id & 0xFF);
  38                 id >>= 8;
  39         }
  40
  41 }
  42
  43 static void cont_free( Datum *cont )
  44 {
  45         ch_free( cont->dptr );
  46 }
  47
  48 /* Allocate an ID_BLOCK with room for nids ids */
  49 ID_BLOCK *
  50 idl_alloc( unsigned int nids )
  51 {
  52         ID_BLOCK        *new;
  53
  54         /* nmax + nids + space for the ids */
  55         new = (ID_BLOCK *) ch_calloc( (ID_BLOCK_IDS_OFFSET + nids), sizeof(ID) );
  56         ID_BLOCK_NMAX(new) = nids;
  57         ID_BLOCK_NIDS(new) = 0;
  58
  59         return( new );
  60 }
  61
  62
  63 /* Allocate an empty ALLIDS ID_BLOCK */
  64 ID_BLOCK        *
  65 idl_allids( Backend *be )
  66 {
  67         ID_BLOCK        *idl;
  68
  69         idl = idl_alloc( 0 );
  70         ID_BLOCK_NMAX(idl) = ID_BLOCK_ALLIDS_VALUE;
  71         ID_BLOCK_NIDS(idl) = next_id_get( be );
  72
  73         return( idl );
  74 }
  75
  76 /* Free an ID_BLOCK */
  77 void
  78 idl_free( ID_BLOCK *idl )
  79 {
  80         if ( idl == NULL ) {
  81                 Debug( LDAP_DEBUG_TRACE,
  82                         "idl_free: called with NULL pointer\n",
  83                         0, 0, 0 );
  84                 return;
  85         }
  86
  87         free( (char *) idl );
  88 }
  89
  90
  91 /* Fetch an single ID_BLOCK from the cache */
  92 static ID_BLOCK *
  93 idl_fetch_one(
  94     Backend             *be,
  95     DBCache     *db,
  96     Datum               key
  97 )
  98 {
  99         Datum   data;
 100         ID_BLOCK        *idl;
 101
 102         /* Debug( LDAP_DEBUG_TRACE, "=> idl_fetch_one\n", 0, 0, 0 ); */
 103
 104         data = ldbm_cache_fetch( db, key );
 105
 106         if( data.dptr == NULL ) {
 107                 return NULL;
 108         }
 109
 110         idl = idl_dup((ID_BLOCK *) data.dptr);
 111
 112         ldbm_datum_free( db->dbc_db, data );
 113
 114         return idl;
 115 }
 116
 117
 118 /* Fetch a set of ID_BLOCKs from the cache
 119  *      if not INDIRECT
 120  *              if block return is an ALLIDS block,
 121  *                      return an new ALLIDS block
 122  *              otherwise
 123  *                      return block
 124  *      construct super block from all blocks referenced by INDIRECT block
 125  *      return super block
 126  */
 127 ID_BLOCK *
 128 idl_fetch(
 129     Backend             *be,
 130     DBCache     *db,
 131     Datum               key
 132 )
 133 {
 134         Datum   data;
 135         ID_BLOCK        *idl;
 136         ID_BLOCK        **tmp;
 137         int     i, nids;
 138
 139         idl = idl_fetch_one( be, db, key );
 140
 141         if ( idl == NULL ) {
 142                 return NULL;
 143         }
 144
 145         if ( ID_BLOCK_ALLIDS(idl) ) {
 146                 /* all ids block */
 147                 /* make sure we have the current value of highest id */
 148                 idl_free( idl );
 149                 idl = idl_allids( be );
 150
 151                 return( idl );
 152         }
 153
 154         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 155                 /* regular block */
 156                 return( idl );
 157         }
 158
 159         /*
 160          * this is an indirect block which points to other blocks.
 161          * we need to read in all the blocks it points to and construct
 162          * a big id list containing all the ids, which we will return.
 163          */
 164
 165         /* count the number of blocks & allocate space for pointers to them */
 166         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ )
 167                 ;       /* NULL */
 168         tmp = (ID_BLOCK **) ch_malloc( (i + 1) * sizeof(ID_BLOCK *) );
 169
 170         /* read in all the blocks */
 171         cont_alloc( &data, &key );
 172         nids = 0;
 173         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ ) {
 174                 cont_id( &data, ID_BLOCK_ID(idl, i) );
 175
 176                 if ( (tmp[i] = idl_fetch_one( be, db, data )) == NULL ) {
 177                         Debug( LDAP_DEBUG_ANY,
 178                             "idl_fetch: one returned NULL\n", 0, 0, 0 );
 179                         continue;
 180                 }
 181
 182                 nids += ID_BLOCK_NIDS(tmp[i]);
 183         }
 184         tmp[i] = NULL;
 185         cont_free( &data );
 186         idl_free( idl );
 187
 188         /* allocate space for the big block */
 189         idl = idl_alloc( nids );
 190         ID_BLOCK_NIDS(idl) = nids;
 191         nids = 0;
 192
 193         /* copy in all the ids from the component blocks */
 194         for ( i = 0; tmp[i] != NULL; i++ ) {
 195                 if ( tmp[i] == NULL ) {
 196                         continue;
 197                 }
 198
 199                 AC_MEMCPY(
 200                         (char *) &ID_BLOCK_ID(idl, nids),
 201                         (char *) &ID_BLOCK_ID(tmp[i], 0),
 202                         ID_BLOCK_NIDS(tmp[i]) * sizeof(ID) );
 203                 nids += ID_BLOCK_NIDS(tmp[i]);
 204
 205                 idl_free( tmp[i] );
 206         }
 207         free( (char *) tmp );
 208
 209         Debug( LDAP_DEBUG_TRACE, "<= idl_fetch %ld ids (%ld max)\n",
 210                ID_BLOCK_NIDS(idl), ID_BLOCK_NMAX(idl), 0 );
 211         return( idl );
 212 }
 213
 214
 215 /* store a single block */
 216 static int
 217 idl_store(
 218     Backend             *be,
 219     DBCache     *db,
 220     Datum               key,
 221     ID_BLOCK            *idl
 222 )
 223 {
 224         int     rc, flags;
 225         Datum   data;
 226         struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 227
 228         ldbm_datum_init( data );
 229
 230         /* Debug( LDAP_DEBUG_TRACE, "=> idl_store\n", 0, 0, 0 ); */
 231
 232         data.dptr = (char *) idl;
 233         data.dsize = (ID_BLOCK_IDS_OFFSET + ID_BLOCK_NMAX(idl)) * sizeof(ID);
 234
 235 #ifdef LDBM_DEBUG
 236         Statslog( LDAP_DEBUG_STATS, "<= idl_store(): rc=%d\n",
 237                 rc, 0, 0, 0, 0 );
 238 #endif
 239
 240         flags = LDBM_REPLACE;
 241         rc = ldbm_cache_store( db, key, data, flags );
 242
 243         /* Debug( LDAP_DEBUG_TRACE, "<= idl_store %d\n", rc, 0, 0 ); */
 244         return( rc );
 245 }
 246
 247 /* split the block at id
 248  *      locate ID greater than or equal to id.
 249  */
 250 static void
 251 idl_split_block(
 252     ID_BLOCK    *b,
 253     ID          id,
 254     ID_BLOCK    **right,
 255     ID_BLOCK    **left
 256 )
 257 {
 258         unsigned int    nr, nl;
 259
 260         /* find where to split the block *//* XXX linear search XXX */
 261         for ( nr = 0; nr < ID_BLOCK_NIDS(b) && id > ID_BLOCK_ID(b, nr); nr++ )
 262                 ;       /* NULL */
 263
 264         nl = ID_BLOCK_NIDS(b) - nr;
 265
 266         *right = idl_alloc( nr == 0 ? 1 : nr );
 267         *left = idl_alloc( nl + (nr == 0 ? 0 : 1));
 268
 269         /*
 270          * everything before the id being inserted in the first block
 271          * unless there is nothing, in which case the id being inserted
 272          * goes there.
 273          */
 274         if ( nr == 0 ) {
 275                 ID_BLOCK_NIDS(*right) = 1;
 276                 ID_BLOCK_ID(*right, 0) = id;
 277         } else {
 278                 AC_MEMCPY(
 279                         (char *) &ID_BLOCK_ID(*right, 0),
 280                         (char *) &ID_BLOCK_ID(b, 0),
 281                         nr * sizeof(ID) );
 282                 ID_BLOCK_NIDS(*right) = nr;
 283                 ID_BLOCK_ID(*left, 0) = id;
 284         }
 285
 286         /* the id being inserted & everything after in the second block */
 287         AC_MEMCPY(
 288                 (char *) &ID_BLOCK_ID(*left, (nr == 0 ? 0 : 1)),
 289             (char *) &ID_BLOCK_ID(b, nr),
 290                 nl * sizeof(ID) );
 291         ID_BLOCK_NIDS(*left) = nl + (nr == 0 ? 0 : 1);
 292 }
 293
 294
 295 /*
 296  * idl_change_first - called when an indirect block's first key has
 297  * changed, meaning it needs to be stored under a new key, and the
 298  * header block pointing to it needs updating.
 299  */
 300 static int
 301 idl_change_first(
 302     Backend             *be,
 303     DBCache     *db,
 304     Datum               hkey,           /* header block key     */
 305     ID_BLOCK            *h,             /* header block         */
 306     int                 pos,            /* pos in h to update   */
 307     Datum               bkey,           /* data block key       */
 308     ID_BLOCK            *b              /* data block           */
 309 )
 310 {
 311         int     rc;
 312
 313         /* Debug( LDAP_DEBUG_TRACE, "=> idl_change_first\n", 0, 0, 0 ); */
 314
 315         /* delete old key block */
 316         if ( (rc = ldbm_cache_delete( db, bkey )) != 0 ) {
 317                 Debug( LDAP_DEBUG_ANY,
 318                     "idl_change_first: ldbm_cache_delete returned %d\n",
 319                         rc, 0, 0 );
 320                 return( rc );
 321         }
 322
 323         /* write block with new key */
 324         cont_id( &bkey, ID_BLOCK_ID(b, 0) );
 325
 326         if ( (rc = idl_store( be, db, bkey, b )) != 0 ) {
 327                 Debug( LDAP_DEBUG_ANY,
 328                     "idl_change_first: idl_store returned %d\n", rc, 0, 0 );
 329                 return( rc );
 330         }
 331
 332         /* update + write indirect header block */
 333         ID_BLOCK_ID(h, pos) = ID_BLOCK_ID(b, 0);
 334         if ( (rc = idl_store( be, db, hkey, h )) != 0 ) {
 335                 Debug( LDAP_DEBUG_ANY,
 336                     "idl_change_first: idl_store returned %d\n", rc, 0, 0 );
 337                 return( rc );
 338         }
 339
 340         return( 0 );
 341 }
 342
 343
 344 int
 345 idl_insert_key(
 346     Backend             *be,
 347     DBCache     *db,
 348     Datum               key,
 349     ID                  id
 350 )
 351 {
 352         int     i, j, first, rc;
 353         ID_BLOCK        *idl, *tmp, *tmp2, *tmp3;
 354         Datum   k2;
 355
 356         if ( (idl = idl_fetch_one( be, db, key )) == NULL ) {
 357                 idl = idl_alloc( 1 );
 358                 ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)++) = id;
 359                 rc = idl_store( be, db, key, idl );
 360
 361                 idl_free( idl );
 362                 return( rc );
 363         }
 364
 365         if ( ID_BLOCK_ALLIDS( idl ) ) {
 366                 /* ALLIDS */
 367                 idl_free( idl );
 368                 return 0;
 369         }
 370
 371         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 372                 /* regular block */
 373                 switch ( idl_insert( &idl, id, db->dbc_maxids ) ) {
 374                 case 0:         /* id inserted - store the updated block */
 375                 case 1:
 376                         rc = idl_store( be, db, key, idl );
 377                         break;
 378
 379                 case 2:         /* id already there - nothing to do */
 380                         rc = 0;
 381                         break;
 382
 383                 case 3:         /* id not inserted - block must be split */
 384                         /* check threshold for marking this an all-id block */
 385                         if ( db->dbc_maxindirect < 2 ) {
 386                                 idl_free( idl );
 387                                 idl = idl_allids( be );
 388                                 rc = idl_store( be, db, key, idl );
 389                                 break;
 390                         }
 391
 392                         idl_split_block( idl, id, &tmp, &tmp2 );
 393                         idl_free( idl );
 394
 395                         /* create the header indirect block */
 396                         idl = idl_alloc( 3 );
 397                         ID_BLOCK_NMAX(idl) = 3;
 398                         ID_BLOCK_NIDS(idl) = ID_BLOCK_INDIRECT_VALUE;
 399                         ID_BLOCK_ID(idl, 0) = ID_BLOCK_ID(tmp, 0);
 400                         ID_BLOCK_ID(idl, 1) = ID_BLOCK_ID(tmp2, 0);
 401                         ID_BLOCK_ID(idl, 2) = NOID;
 402
 403                         /* store it */
 404                         rc = idl_store( be, db, key, idl );
 405
 406                         cont_alloc( &k2, &key );
 407                         cont_id( &k2, ID_BLOCK_ID(tmp, 0) );
 408
 409                         rc = idl_store( be, db, k2, tmp );
 410
 411                         cont_id( &k2, ID_BLOCK_ID(tmp2, 0) );
 412                         rc = idl_store( be, db, k2, tmp2 );
 413
 414                         cont_free( &k2 );
 415
 416                         idl_free( tmp );
 417                         idl_free( tmp2 );
 418                         break;
 419                 }
 420
 421                 idl_free( idl );
 422                 return( rc );
 423         }
 424
 425         /*
 426          * this is an indirect block which points to other blocks.
 427          * we need to read in the block into which the id should be
 428          * inserted, then insert the id and store the block.  we might
 429          * have to split the block if it is full, which means we also
 430          * need to write a new "header" block.
 431          */
 432
 433         /* select the block to try inserting into *//* XXX linear search XXX */
 434         for ( i = 0; !ID_BLOCK_NOID(idl, i) && id > ID_BLOCK_ID(idl, i); i++ )
 435                 ;       /* NULL */
 436
 437         if ( i != 0 ) {
 438                 i--;
 439                 first = 0;
 440         } else {
 441                 first = 1;
 442         }
 443
 444         /* get the block */
 445         cont_alloc( &k2, &key );
 446         cont_id( &k2, ID_BLOCK_ID(idl, i) );
 447
 448         if ( (tmp = idl_fetch_one( be, db, k2 )) == NULL ) {
 449                 Debug( LDAP_DEBUG_ANY, "idl_insert_key: nonexistent continuation block\n",
 450                     0, 0, 0 );
 451                 cont_free( &k2 );
 452                 idl_free( idl );
 453                 return( -1 );
 454         }
 455
 456         /* insert the id */
 457         switch ( idl_insert( &tmp, id, db->dbc_maxids ) ) {
 458         case 0:         /* id inserted ok */
 459                 if ( (rc = idl_store( be, db, k2, tmp )) != 0 ) {
 460                         Debug( LDAP_DEBUG_ANY,
 461                             "idl_insert_key: idl_store returned %d\n", rc, 0, 0 );
 462                 }
 463                 break;
 464
 465         case 1:         /* id inserted - first id in block has changed */
 466                 /*
 467                  * key for this block has changed, so we have to
 468                  * write the block under the new key, delete the
 469                  * old key block + update and write the indirect
 470                  * header block.
 471                  */
 472
 473                 rc = idl_change_first( be, db, key, idl, i, k2, tmp );
 474                 break;
 475
 476         case 2:         /* id not inserted - already there, do nothing */
 477                 rc = 0;
 478                 break;
 479
 480         case 3:         /* id not inserted - block is full */
 481                 /*
 482                  * first, see if it will fit in the next block,
 483                  * without splitting, unless we're trying to insert
 484                  * into the beginning of the first block.
 485                  */
 486
 487                 /* is there a next block? */
 488                 if ( !first && !ID_BLOCK_NOID(idl, i + 1) ) {
 489                         /* read it in */
 490                         cont_alloc( &k2, &key );
 491                         cont_id( &k2, ID_BLOCK_ID(idl, i) );
 492                         if ( (tmp2 = idl_fetch_one( be, db, k2 )) == NULL ) {
 493                                 Debug( LDAP_DEBUG_ANY,
 494                                     "idl_insert_key: idl_fetch_one returned NULL\n",
 495                                     0, 0, 0 );
 496                                 /* split the original block */
 497                                 cont_free( &k2 );
 498                                 goto split;
 499                         }
 500
 501                         /* If the new id is less than the last id in the
 502                          * current block, it must not be put into the next
 503                          * block. Push the last id of the current block
 504                          * into the next block instead.
 505                          */
 506                         if (id < ID_BLOCK_ID(tmp, ID_BLOCK_NIDS(tmp) - 1)) {
 507                             ID id2 = ID_BLOCK_ID(tmp, ID_BLOCK_NIDS(tmp) - 1);
 508                             Datum k3;
 509
 510                             ldbm_datum_init( k3 );
 511
 512                             --ID_BLOCK_NIDS(tmp);
 513                             /* This must succeed since we just popped one
 514                              * ID off the end of it.
 515                              */
 516                             rc = idl_insert( &tmp, id, db->dbc_maxids );
 517
 518                                 k3.dptr = ch_malloc(k2.dsize);
 519                                 k3.dsize = k2.dsize;
 520                                 AC_MEMCPY(k3.dptr, k2.dptr, k3.dsize);
 521                             if ( (rc = idl_store( be, db, k3, tmp )) != 0 ) {
 522                                 Debug( LDAP_DEBUG_ANY,
 523                             "idl_insert_key: idl_store returned %d\n", rc, 0, 0 );
 524                             }
 525
 526                                 free( k3.dptr );
 527
 528                             id = id2;
 529                             /* This new id will necessarily be inserted
 530                              * as the first id of the next block by the
 531                              * following switch() statement.
 532                              */
 533                         }
 534
 535                         switch ( (rc = idl_insert( &tmp2, id,
 536                             db->dbc_maxids )) ) {
 537                         case 1:         /* id inserted first in block */
 538                                 rc = idl_change_first( be, db, key, idl,
 539                                     i + 1, k2, tmp2 );
 540                                 /* FALL */
 541
 542                         case 2:         /* id already there - how? */
 543                         case 0:         /* id inserted: this can never be
 544                                          * the result of idl_insert, because
 545                                          * we guaranteed that idl_change_first
 546                                          * will always be called.
 547                                          */
 548                                 if ( rc == 2 ) {
 549                                         Debug( LDAP_DEBUG_ANY,
 550                                             "idl_insert_key: id %ld already in next block\n",
 551                                             id, 0, 0 );
 552                                 }
 553
 554                                 assert( 0 ); /* not yet implemented */
 555                                 idl_free( tmp );
 556                                 idl_free( tmp2 );
 557                                 idl_free( idl );
 558                                 return( 0 );
 559
 560                         case 3:         /* split the original block */
 561                                 break;
 562                         }
 563
 564                         idl_free( tmp2 );
 565                 }
 566
 567 split:
 568                 /*
 569                  * must split the block, write both new blocks + update
 570                  * and write the indirect header block.
 571                  */
 572
 573                 rc = 0; /* optimistic */
 574
 575
 576                 /* count how many indirect blocks *//* XXX linear count XXX */
 577                 for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ )
 578                         ;       /* NULL */
 579
 580                 /* check it against all-id thresholed */
 581                 if ( j + 1 > db->dbc_maxindirect ) {
 582                         /*
 583                          * we've passed the all-id threshold, meaning
 584                          * that this set of blocks should be replaced
 585                          * by a single "all-id" block.  our job: delete
 586                          * all the indirect blocks, and replace the header
 587                          * block by an all-id block.
 588                          */
 589
 590                         /* delete all indirect blocks */
 591                         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ ) {
 592                                 cont_id( &k2, ID_BLOCK_ID(idl, j) );
 593
 594                                 rc = ldbm_cache_delete( db, k2 );
 595                         }
 596
 597                         /* store allid block in place of header block */
 598                         idl_free( idl );
 599                         idl = idl_allids( be );
 600                         rc = idl_store( be, db, key, idl );
 601
 602                         cont_free( &k2 );
 603                         idl_free( idl );
 604                         idl_free( tmp );
 605                         return( rc );
 606                 }
 607
 608                 idl_split_block( tmp, id, &tmp2, &tmp3 );
 609                 idl_free( tmp );
 610
 611                 /* create a new updated indirect header block */
 612                 tmp = idl_alloc( ID_BLOCK_NMAX(idl) + 1 );
 613                 ID_BLOCK_NIDS(tmp) = ID_BLOCK_INDIRECT_VALUE;
 614                 /* everything up to the split block */
 615                 AC_MEMCPY(
 616                         (char *) &ID_BLOCK_ID(tmp, 0),
 617                         (char *) &ID_BLOCK_ID(idl, 0),
 618                     i * sizeof(ID) );
 619                 /* the two new blocks */
 620                 ID_BLOCK_ID(tmp, i) = ID_BLOCK_ID(tmp2, 0);
 621                 ID_BLOCK_ID(tmp, i + 1) = ID_BLOCK_ID(tmp3, 0);
 622                 /* everything after the split block */
 623                 AC_MEMCPY(
 624                         (char *) &ID_BLOCK_ID(tmp, i + 2),
 625                         (char *) &ID_BLOCK_ID(idl, i + 1),
 626                         (ID_BLOCK_NMAX(idl) - i - 1) * sizeof(ID) );
 627
 628                 /* store the header block */
 629                 rc = idl_store( be, db, key, tmp );
 630
 631                 /* store the first id block */
 632                 cont_id( &k2, ID_BLOCK_ID(tmp2, 0) );
 633                 rc = idl_store( be, db, k2, tmp2 );
 634
 635                 /* store the second id block */
 636                 cont_id( &k2, ID_BLOCK_ID(tmp3, 0) );
 637                 rc = idl_store( be, db, k2, tmp3 );
 638
 639                 idl_free( tmp2 );
 640                 idl_free( tmp3 );
 641                 break;
 642         }
 643
 644         cont_free( &k2 );
 645         idl_free( tmp );
 646         idl_free( idl );
 647         return( rc );
 648 }
 649
 650
 651 /*
 652  * idl_insert - insert an id into an id list.
 653  *
 654  *      returns
 655  *              0       id inserted
 656  *              1       id inserted, first id in block has changed
 657  *              2       id not inserted, already there
 658  *              3       id not inserted, block must be split
 659  */
 660 int
 661 idl_insert( ID_BLOCK **idl, ID id, unsigned int maxids )
 662 {
 663         unsigned int    i;
 664
 665         if ( ID_BLOCK_ALLIDS( *idl ) ) {
 666                 return( 2 );    /* already there */
 667         }
 668
 669         /* is it already there? *//* XXX linear search XXX */
 670         for ( i = 0; i < ID_BLOCK_NIDS(*idl) && id > ID_BLOCK_ID(*idl, i); i++ ) {
 671                 ;       /* NULL */
 672         }
 673         if ( i < ID_BLOCK_NIDS(*idl) && ID_BLOCK_ID(*idl, i) == id ) {
 674                 return( 2 );    /* already there */
 675         }
 676
 677         /* do we need to make room for it? */
 678         if ( ID_BLOCK_NIDS(*idl) == ID_BLOCK_NMAX(*idl) ) {
 679                 /* make room or indicate block needs splitting */
 680                 if ( ID_BLOCK_NMAX(*idl) >= maxids ) {
 681                         return( 3 );    /* block needs splitting */
 682                 }
 683
 684                 ID_BLOCK_NMAX(*idl) *= 2;
 685                 if ( ID_BLOCK_NMAX(*idl) > maxids ) {
 686                         ID_BLOCK_NMAX(*idl) = maxids;
 687                 }
 688                 *idl = (ID_BLOCK *) ch_realloc( (char *) *idl,
 689                     (ID_BLOCK_NMAX(*idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
 690         }
 691
 692         /* make a slot for the new id */
 693         AC_MEMCPY( &ID_BLOCK_ID(*idl, i+1), &ID_BLOCK_ID(*idl, i),
 694                     (ID_BLOCK_NIDS(*idl) - i) * sizeof(ID) );
 695
 696         ID_BLOCK_ID(*idl, i) = id;
 697         ID_BLOCK_NIDS(*idl)++;
 698         (void) memset(
 699                 (char *) &ID_BLOCK_ID((*idl), ID_BLOCK_NIDS(*idl)),
 700                 '\0',
 701             (ID_BLOCK_NMAX(*idl) - ID_BLOCK_NIDS(*idl)) * sizeof(ID) );
 702
 703         return( i == 0 ? 1 : 0 );       /* inserted - first id changed or not */
 704 }
 705
 706
 707 int
 708 idl_delete_key (
 709         Backend         *be,
 710         DBCache  *db,
 711         Datum           key,
 712         ID              id
 713 )
 714 {
 715         Datum  data;
 716         ID_BLOCK *idl;
 717         unsigned i;
 718         int j, nids;
 719
 720         if ( (idl = idl_fetch_one( be, db, key ) ) == NULL )
 721         {
 722                 /* It wasn't found.  Hmm... */
 723                 return -1;
 724         }
 725
 726         if ( ID_BLOCK_ALLIDS( idl ) ) {
 727                 idl_free( idl );
 728                 return 0;
 729         }
 730
 731         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 732                 for ( i=0; i < ID_BLOCK_NIDS(idl); i++ ) {
 733                         if ( ID_BLOCK_ID(idl, i) == id ) {
 734                                 if( --ID_BLOCK_NIDS(idl) == 0 ) {
 735                                         ldbm_cache_delete( db, key );
 736
 737                                 } else {
 738                                         AC_MEMCPY(
 739                                                 &ID_BLOCK_ID(idl, i),
 740                                                 &ID_BLOCK_ID(idl, i+1),
 741                                                 (ID_BLOCK_NIDS(idl)-i) * sizeof(ID) );
 742
 743                                         ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)) = NOID;
 744
 745                                         idl_store( be, db, key, idl );
 746                                 }
 747
 748                                 idl_free( idl );
 749                                 return 0;
 750                         }
 751                         /*  We didn't find the ID.  Hmmm... */
 752                 }
 753                 idl_free( idl );
 754                 return -1;
 755         }
 756
 757         /* We have to go through an indirect block and find the ID
 758            in the list of IDL's
 759            */
 760         for ( nids = 0; !ID_BLOCK_NOID(idl, nids); nids++ )
 761                 ;       /* NULL */
 762
 763         cont_alloc( &data, &key );
 764
 765         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ )
 766         {
 767                 ID_BLOCK *tmp;
 768                 cont_id( &data, ID_BLOCK_ID(idl, j) );
 769
 770                 if ( (tmp = idl_fetch_one( be, db, data )) == NULL ) {
 771                         Debug( LDAP_DEBUG_ANY,
 772                             "idl_delete_key: idl_fetch of returned NULL\n", 0, 0, 0 );
 773                         continue;
 774                 }
 775                 /*
 776                    Now try to find the ID in tmp
 777                 */
 778                 for ( i=0; i < ID_BLOCK_NIDS(tmp); i++ )
 779                 {
 780                         if ( ID_BLOCK_ID(tmp, i) == id )
 781                         {
 782                                 AC_MEMCPY(
 783                                         &ID_BLOCK_ID(tmp, i),
 784                                         &ID_BLOCK_ID(tmp, i+1),
 785                                         (ID_BLOCK_NIDS(tmp)-(i+1)) * sizeof(ID));
 786                                 ID_BLOCK_ID(tmp, ID_BLOCK_NIDS(tmp)-1 ) = NOID;
 787                                 ID_BLOCK_NIDS(tmp)--;
 788
 789                                 if ( ID_BLOCK_NIDS(tmp) ) {
 790                                         idl_store ( be, db, data, tmp );
 791
 792                                 } else {
 793                                         ldbm_cache_delete( db, data );
 794                                         AC_MEMCPY(
 795                                                 &ID_BLOCK_ID(idl, j),
 796                                                 &ID_BLOCK_ID(idl, j+1),
 797                                                 (nids-(j+1)) * sizeof(ID));
 798                                         ID_BLOCK_ID(idl, nids-1) = NOID;
 799                                         nids--;
 800                                         if ( ! nids )
 801                                                 ldbm_cache_delete( db, key );
 802                                         else
 803                                                 idl_store( be, db, key, idl );
 804                                 }
 805                                 idl_free( tmp );
 806                                 cont_free( &data );
 807                                 idl_free( idl );
 808                                 return 0;
 809                         }
 810                 }
 811                 idl_free( tmp );
 812         }
 813
 814         cont_free( &data );
 815         idl_free( idl );
 816         return -1;
 817 }
 818
 819
 820 /* return a duplicate of a single ID_BLOCK */
 821 static ID_BLOCK *
 822 idl_dup( ID_BLOCK *idl )
 823 {
 824         ID_BLOCK        *new;
 825
 826         if ( idl == NULL ) {
 827                 return( NULL );
 828         }
 829
 830         new = idl_alloc( ID_BLOCK_NMAX(idl) );
 831
 832         AC_MEMCPY(
 833                 (char *) new,
 834                 (char *) idl,
 835                 (ID_BLOCK_NMAX(idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
 836
 837         return( new );
 838 }
 839
 840
 841 /* return the smaller ID_BLOCK */
 842 static ID_BLOCK *
 843 idl_min( ID_BLOCK *a, ID_BLOCK *b )
 844 {
 845         return( ID_BLOCK_NIDS(a) > ID_BLOCK_NIDS(b) ? b : a );
 846 }
 847
 848
 849 /*
 850  * idl_intersection - return a intersection b
 851  */
 852 ID_BLOCK *
 853 idl_intersection(
 854     Backend     *be,
 855     ID_BLOCK    *a,
 856     ID_BLOCK    *b
 857 )
 858 {
 859         unsigned int    ai, bi, ni;
 860         ID_BLOCK                *n;
 861
 862         if ( a == NULL || b == NULL ) {
 863                 return( NULL );
 864         }
 865         if ( ID_BLOCK_ALLIDS( a ) ) {
 866                 return( idl_dup( b ) );
 867         }
 868         if ( ID_BLOCK_ALLIDS( b ) ) {
 869                 return( idl_dup( a ) );
 870         }
 871
 872         n = idl_dup( idl_min( a, b ) );
 873
 874         for ( ni = 0, ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
 875                 for ( ;
 876                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
 877                         bi++ )
 878                 {
 879                         ;       /* NULL */
 880                 }
 881
 882                 if ( bi == ID_BLOCK_NIDS(b) ) {
 883                         break;
 884                 }
 885
 886                 if ( ID_BLOCK_ID(b, bi) == ID_BLOCK_ID(a, ai) ) {
 887                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 888                 }
 889         }
 890
 891         if ( ni == 0 ) {
 892                 idl_free( n );
 893                 return( NULL );
 894         }
 895         ID_BLOCK_NIDS(n) = ni;
 896
 897         return( n );
 898 }
 899
 900
 901 /*
 902  * idl_union - return a union b
 903  */
 904 ID_BLOCK *
 905 idl_union(
 906     Backend     *be,
 907     ID_BLOCK    *a,
 908     ID_BLOCK    *b
 909 )
 910 {
 911         unsigned int    ai, bi, ni;
 912         ID_BLOCK                *n;
 913
 914         if ( a == NULL ) {
 915                 return( idl_dup( b ) );
 916         }
 917         if ( b == NULL ) {
 918                 return( idl_dup( a ) );
 919         }
 920         if ( ID_BLOCK_ALLIDS( a ) || ID_BLOCK_ALLIDS( b ) ) {
 921                 return( idl_allids( be ) );
 922         }
 923
 924         if ( ID_BLOCK_NIDS(b) < ID_BLOCK_NIDS(a) ) {
 925                 n = a;
 926                 a = b;
 927                 b = n;
 928         }
 929
 930         n = idl_alloc( ID_BLOCK_NIDS(a) + ID_BLOCK_NIDS(b) );
 931
 932         for ( ni = 0, ai = 0, bi = 0;
 933                 ai < ID_BLOCK_NIDS(a) && bi < ID_BLOCK_NIDS(b);
 934                 )
 935         {
 936                 if ( ID_BLOCK_ID(a, ai) < ID_BLOCK_ID(b, bi) ) {
 937                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai++);
 938
 939                 } else if ( ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai) ) {
 940                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi++);
 941
 942                 } else {
 943                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 944                         ai++, bi++;
 945                 }
 946         }
 947
 948         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
 949                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 950         }
 951         for ( ; bi < ID_BLOCK_NIDS(b); bi++ ) {
 952                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi);
 953         }
 954         ID_BLOCK_NIDS(n) = ni;
 955
 956         return( n );
 957 }
 958
 959
 960 /*
 961  * idl_notin - return a intersection ~b (or a minus b)
 962  */
 963 ID_BLOCK *
 964 idl_notin(
 965     Backend     *be,
 966     ID_BLOCK    *a,
 967     ID_BLOCK    *b
 968 )
 969 {
 970         unsigned int    ni, ai, bi;
 971         ID_BLOCK                *n;
 972
 973         if ( a == NULL ) {
 974                 return( NULL );
 975         }
 976         if ( b == NULL || ID_BLOCK_ALLIDS( b )) {
 977                 return( idl_dup( a ) );
 978         }
 979
 980         if ( ID_BLOCK_ALLIDS( a ) ) {
 981                 n = idl_alloc( SLAPD_LDBM_MIN_MAXIDS );
 982                 ni = 0;
 983
 984                 for ( ai = 1, bi = 0;
 985                         ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n) && bi < ID_BLOCK_NMAX(b);
 986                         ai++ )
 987                 {
 988                         if ( ID_BLOCK_ID(b, bi) == ai ) {
 989                                 bi++;
 990                         } else {
 991                                 ID_BLOCK_ID(n, ni++) = ai;
 992                         }
 993                 }
 994
 995                 for ( ; ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n); ai++ ) {
 996                         ID_BLOCK_ID(n, ni++) = ai;
 997                 }
 998
 999                 if ( ni == ID_BLOCK_NMAX(n) ) {
1000                         idl_free( n );
1001                         return( idl_allids( be ) );
1002                 } else {
1003                         ID_BLOCK_NIDS(n) = ni;
1004                         return( n );
1005                 }
1006         }
1007
1008         n = idl_dup( a );
1009
1010         ni = 0;
1011         for ( ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
1012                 for ( ;
1013                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
1014                     bi++ )
1015                 {
1016                         ;       /* NULL */
1017                 }
1018
1019                 if ( bi == ID_BLOCK_NIDS(b) ) {
1020                         break;
1021                 }
1022
1023                 if ( ID_BLOCK_ID(b, bi) != ID_BLOCK_ID(a, ai) ) {
1024                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
1025                 }
1026         }
1027
1028         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
1029                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
1030         }
1031         ID_BLOCK_NIDS(n) = ni;
1032
1033         return( n );
1034 }
1035
1036 /*      return the first ID in the block
1037  *      if ALLIDS block
1038  *              NIDS > 1 return 1
1039  *              otherwise return NOID
1040  *      otherwise return first ID
1041  *
1042  *      cursor is set to 1
1043  */
1044 ID
1045 idl_firstid( ID_BLOCK *idl, ID *cursor )
1046 {
1047         *cursor = 1;
1048
1049         if ( idl == NULL || ID_BLOCK_NIDS(idl) == 0 ) {
1050                 return( NOID );
1051         }
1052
1053         if ( ID_BLOCK_ALLIDS( idl ) ) {
1054                 return( ID_BLOCK_NIDS(idl) > 1 ? 1 : NOID );
1055         }
1056
1057         return( ID_BLOCK_ID(idl, 0) );
1058 }
1059
1060 /*      return next ID
1061  *      if ALLIDS block, cursor is id.
1062  *              increment id
1063  *              if id < NIDS return id
1064  *              otherwise NOID.
1065  *      otherwise cursor is index into block
1066  *              if index < nids
1067  *                      return id at index then increment
1068  */
1069 ID
1070 idl_nextid( ID_BLOCK *idl, ID *cursor )
1071 {
1072         if ( ID_BLOCK_ALLIDS( idl ) ) {
1073                 if( ++(*cursor) < ID_BLOCK_NIDS(idl) ) {
1074                         return *cursor;
1075                 } else {
1076                         return NOID;
1077                 }
1078         }
1079
1080         if ( *cursor < ID_BLOCK_NIDS(idl) ) {
1081                 return( ID_BLOCK_ID(idl, (*cursor)++) );
1082         }
1083
1084         return( NOID );
1085 }