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

   1 /* idl.c - ldap id list handling routines */
   2 /*
   3  * Copyright 1998-1999 The OpenLDAP Foundation, All Rights Reserved.
   4  * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
   5  */
   6
   7 #include "portable.h"
   8
   9 #include <stdio.h>
  10
  11 #include <ac/string.h>
  12 #include <ac/socket.h>
  13
  14 #include "ldap_defaults.h"
  15 #include "slap.h"
  16 #include "back-ldbm.h"
  17
  18 static ID_BLOCK* idl_dup( ID_BLOCK *idl );
  19
  20 /* Allocate an ID_BLOCK with room for nids ids */
  21 ID_BLOCK *
  22 idl_alloc( unsigned int nids )
  23 {
  24         ID_BLOCK        *new;
  25
  26         /* nmax + nids + space for the ids */
  27         new = (ID_BLOCK *) ch_calloc( (ID_BLOCK_IDS_OFFSET + nids), sizeof(ID) );
  28         ID_BLOCK_NMAX(new) = nids;
  29         ID_BLOCK_NIDS(new) = 0;
  30
  31         return( new );
  32 }
  33
  34
  35 /* Allocate an empty ALLIDS ID_BLOCK */
  36 ID_BLOCK        *
  37 idl_allids( Backend *be )
  38 {
  39         ID_BLOCK        *idl;
  40
  41         idl = idl_alloc( 0 );
  42         ID_BLOCK_NMAX(idl) = ID_BLOCK_ALLIDS_VALUE;
  43         ID_BLOCK_NIDS(idl) = next_id_get( be );
  44
  45         return( idl );
  46 }
  47
  48 /* Free an ID_BLOCK */
  49 void
  50 idl_free( ID_BLOCK *idl )
  51 {
  52         if ( idl == NULL ) {
  53                 Debug( LDAP_DEBUG_TRACE,
  54                         "idl_free: called with NULL pointer\n",
  55                         0, 0, 0 );
  56                 return;
  57         }
  58
  59         free( (char *) idl );
  60 }
  61
  62
  63 /* Fetch an single ID_BLOCK from the cache */
  64 static ID_BLOCK *
  65 idl_fetch_one(
  66     Backend             *be,
  67     DBCache     *db,
  68     Datum               key
  69 )
  70 {
  71         Datum   data;
  72         ID_BLOCK        *idl;
  73
  74         /* Debug( LDAP_DEBUG_TRACE, "=> idl_fetch_one\n", 0, 0, 0 ); */
  75
  76         data = ldbm_cache_fetch( db, key );
  77
  78         if( data.dptr == NULL ) {
  79                 return NULL;
  80         }
  81
  82         idl = idl_dup((ID_BLOCK *) data.dptr);
  83
  84         ldbm_datum_free( db->dbc_db, data );
  85
  86         return idl;
  87 }
  88
  89
  90 /* Fetch a set of ID_BLOCKs from the cache
  91  *      if not INDIRECT
  92  *              if block return is an ALLIDS block,
  93  *                      return an new ALLIDS block
  94  *              otherwise
  95  *                      return block
  96  *      construct super block from all blocks referenced by INDIRECT block
  97  *      return super block
  98  */
  99 ID_BLOCK *
 100 idl_fetch(
 101     Backend             *be,
 102     DBCache     *db,
 103     Datum               key
 104 )
 105 {
 106         Datum   data;
 107         ID_BLOCK        *idl;
 108         ID_BLOCK        **tmp;
 109         char    *kstr;
 110         int     i, nids;
 111
 112         idl = idl_fetch_one( be, db, key );
 113
 114         if ( idl == NULL ) {
 115                 return NULL;
 116         }
 117
 118         if ( ID_BLOCK_ALLIDS(idl) ) {
 119                 /* all ids block */
 120                 /* make sure we have the current value of highest id */
 121                 idl_free( idl );
 122                 idl = idl_allids( be );
 123
 124                 return( idl );
 125         }
 126
 127         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 128                 /* regular block */
 129                 return( idl );
 130         }
 131
 132         /*
 133          * this is an indirect block which points to other blocks.
 134          * we need to read in all the blocks it points to and construct
 135          * a big id list containing all the ids, which we will return.
 136          */
 137
 138         /* count the number of blocks & allocate space for pointers to them */
 139         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ )
 140                 ;       /* NULL */
 141         tmp = (ID_BLOCK **) ch_malloc( (i + 1) * sizeof(ID_BLOCK *) );
 142
 143         /* read in all the blocks */
 144         kstr = (char *) ch_malloc( key.dsize + CONT_SIZE );
 145         nids = 0;
 146         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ ) {
 147                 ldbm_datum_init( data );
 148
 149                 sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 150                         ID_BLOCK_ID(idl, i), key.dptr );
 151
 152                 data.dptr = kstr;
 153                 data.dsize = strlen( kstr ) + 1;
 154
 155                 if ( (tmp[i] = idl_fetch_one( be, db, data )) == NULL ) {
 156                         Debug( LDAP_DEBUG_ANY,
 157                             "idl_fetch of (%s) returns NULL\n", data.dptr, 0, 0 );
 158                         continue;
 159                 }
 160
 161                 nids += ID_BLOCK_NIDS(tmp[i]);
 162         }
 163         tmp[i] = NULL;
 164         free( kstr );
 165         idl_free( idl );
 166
 167         /* allocate space for the big block */
 168         idl = idl_alloc( nids );
 169         ID_BLOCK_NIDS(idl) = nids;
 170         nids = 0;
 171
 172         /* copy in all the ids from the component blocks */
 173         for ( i = 0; tmp[i] != NULL; i++ ) {
 174                 if ( tmp[i] == NULL ) {
 175                         continue;
 176                 }
 177
 178                 SAFEMEMCPY(
 179                         (char *) &ID_BLOCK_ID(idl, nids),
 180                         (char *) &ID_BLOCK_ID(tmp[i], 0),
 181                         ID_BLOCK_NIDS(tmp[i]) * sizeof(ID) );
 182                 nids += ID_BLOCK_NIDS(tmp[i]);
 183
 184                 idl_free( tmp[i] );
 185         }
 186         free( (char *) tmp );
 187
 188         Debug( LDAP_DEBUG_TRACE, "<= idl_fetch %ld ids (%ld max)\n",
 189                ID_BLOCK_NIDS(idl), ID_BLOCK_NMAX(idl), 0 );
 190         return( idl );
 191 }
 192
 193
 194 /* store a single block */
 195 static int
 196 idl_store(
 197     Backend             *be,
 198     DBCache     *db,
 199     Datum               key,
 200     ID_BLOCK            *idl
 201 )
 202 {
 203         int     rc, flags;
 204         Datum   data;
 205         struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 206
 207         ldbm_datum_init( data );
 208
 209         /* Debug( LDAP_DEBUG_TRACE, "=> idl_store\n", 0, 0, 0 ); */
 210
 211         data.dptr = (char *) idl;
 212         data.dsize = (ID_BLOCK_IDS_OFFSET + ID_BLOCK_NMAX(idl)) * sizeof(ID);
 213
 214 #ifdef LDBM_DEBUG
 215         Statslog( LDAP_DEBUG_STATS, "<= idl_store(): rc=%d\n",
 216                 rc, 0, 0, 0, 0 );
 217 #endif
 218
 219         flags = LDBM_REPLACE;
 220         if( li->li_dbcachewsync ) flags |= LDBM_SYNC;
 221         rc = ldbm_cache_store( db, key, data, flags );
 222
 223         /* Debug( LDAP_DEBUG_TRACE, "<= idl_store %d\n", rc, 0, 0 ); */
 224         return( rc );
 225 }
 226
 227 /* split the block at id
 228  *      locate ID greater than or equal to id.
 229  */
 230 static void
 231 idl_split_block(
 232     ID_BLOCK    *b,
 233     ID          id,
 234     ID_BLOCK    **right,
 235     ID_BLOCK    **left
 236 )
 237 {
 238         unsigned int    nr, nl;
 239
 240         /* find where to split the block *//* XXX linear search XXX */
 241         for ( nr = 0; nr < ID_BLOCK_NIDS(b) && id > ID_BLOCK_ID(b, nr); nr++ )
 242                 ;       /* NULL */
 243
 244         nl = ID_BLOCK_NIDS(b) - nr;
 245
 246         *right = idl_alloc( nr == 0 ? 1 : nr );
 247         *left = idl_alloc( nl + (nr == 0 ? 0 : 1));
 248
 249         /*
 250          * everything before the id being inserted in the first block
 251          * unless there is nothing, in which case the id being inserted
 252          * goes there.
 253          */
 254         if ( nr == 0 ) {
 255                 ID_BLOCK_NIDS(*right) = 1;
 256                 ID_BLOCK_ID(*right, 0) = id;
 257         } else {
 258                 SAFEMEMCPY(
 259                         (char *) &ID_BLOCK_ID(*right, 0),
 260                         (char *) &ID_BLOCK_ID(b, 0),
 261                         nr * sizeof(ID) );
 262                 ID_BLOCK_NIDS(*right) = nr;
 263                 ID_BLOCK_ID(*left, 0) = id;
 264         }
 265
 266         /* the id being inserted & everything after in the second block */
 267         SAFEMEMCPY(
 268                 (char *) &ID_BLOCK_ID(*left, (nr == 0 ? 0 : 1)),
 269             (char *) &ID_BLOCK_ID(b, nr),
 270                 nl * sizeof(ID) );
 271         ID_BLOCK_NIDS(*left) = nl + (nr == 0 ? 0 : 1);
 272 }
 273
 274
 275 /*
 276  * idl_change_first - called when an indirect block's first key has
 277  * changed, meaning it needs to be stored under a new key, and the
 278  * header block pointing to it needs updating.
 279  */
 280 static int
 281 idl_change_first(
 282     Backend             *be,
 283     DBCache     *db,
 284     Datum               hkey,           /* header block key     */
 285     ID_BLOCK            *h,             /* header block         */
 286     int                 pos,            /* pos in h to update   */
 287     Datum               bkey,           /* data block key       */
 288     ID_BLOCK            *b              /* data block           */
 289 )
 290 {
 291         int     rc;
 292
 293         /* Debug( LDAP_DEBUG_TRACE, "=> idl_change_first\n", 0, 0, 0 ); */
 294
 295         /* delete old key block */
 296         if ( (rc = ldbm_cache_delete( db, bkey )) != 0 ) {
 297                 Debug( LDAP_DEBUG_ANY,
 298                     "ldbm_delete of (%s) returns %d\n", bkey.dptr, rc,
 299                     0 );
 300                 return( rc );
 301         }
 302
 303         /* write block with new key */
 304         sprintf( bkey.dptr, "%c%ld%s", CONT_PREFIX,
 305                 ID_BLOCK_ID(b, 0), hkey.dptr );
 306
 307         bkey.dsize = strlen( bkey.dptr ) + 1;
 308         if ( (rc = idl_store( be, db, bkey, b )) != 0 ) {
 309                 Debug( LDAP_DEBUG_ANY,
 310                     "idl_store of (%s) returns %d\n", bkey.dptr, rc, 0 );
 311                 return( rc );
 312         }
 313
 314         /* update + write indirect header block */
 315         ID_BLOCK_ID(h, pos) = ID_BLOCK_ID(b, 0);
 316         if ( (rc = idl_store( be, db, hkey, h )) != 0 ) {
 317                 Debug( LDAP_DEBUG_ANY,
 318                     "idl_store of (%s) returns %d\n", hkey.dptr, rc, 0 );
 319                 return( rc );
 320         }
 321
 322         return( 0 );
 323 }
 324
 325
 326 int
 327 idl_insert_key(
 328     Backend             *be,
 329     DBCache     *db,
 330     Datum               key,
 331     ID                  id
 332 )
 333 {
 334         int     i, j, first, rc;
 335         ID_BLOCK        *idl, *tmp, *tmp2, *tmp3;
 336         char    *kstr;
 337         Datum   k2;
 338
 339         ldbm_datum_init( k2 );
 340
 341         if ( (idl = idl_fetch_one( be, db, key )) == NULL ) {
 342 #ifdef LDBM_DEBUG
 343                 Statslog( LDAP_DEBUG_STATS, "=> idl_insert_key(): no key yet\n",
 344                         0, 0, 0, 0, 0 );
 345 #endif
 346
 347                 idl = idl_alloc( 1 );
 348                 ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)++) = id;
 349                 rc = idl_store( be, db, key, idl );
 350
 351                 idl_free( idl );
 352                 return( rc );
 353         }
 354
 355         if ( ID_BLOCK_ALLIDS( idl ) ) {
 356                 /* ALLIDS */
 357                 idl_free( idl );
 358                 return 0;
 359         }
 360
 361         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 362                 /* regular block */
 363                 switch ( idl_insert( &idl, id, db->dbc_maxids ) ) {
 364                 case 0:         /* id inserted - store the updated block */
 365                 case 1:
 366                         rc = idl_store( be, db, key, idl );
 367                         break;
 368
 369                 case 2:         /* id already there - nothing to do */
 370                         rc = 0;
 371                         break;
 372
 373                 case 3:         /* id not inserted - block must be split */
 374                         /* check threshold for marking this an all-id block */
 375                         if ( db->dbc_maxindirect < 2 ) {
 376                                 idl_free( idl );
 377                                 idl = idl_allids( be );
 378                                 rc = idl_store( be, db, key, idl );
 379                                 break;
 380                         }
 381
 382                         idl_split_block( idl, id, &tmp, &tmp2 );
 383                         idl_free( idl );
 384
 385                         /* create the header indirect block */
 386                         idl = idl_alloc( 3 );
 387                         ID_BLOCK_NMAX(idl) = 3;
 388                         ID_BLOCK_NIDS(idl) = ID_BLOCK_INDIRECT_VALUE;
 389                         ID_BLOCK_ID(idl, 0) = ID_BLOCK_ID(tmp, 0);
 390                         ID_BLOCK_ID(idl, 1) = ID_BLOCK_ID(tmp2, 0);
 391                         ID_BLOCK_ID(idl, 2) = NOID;
 392
 393                         /* store it */
 394                         rc = idl_store( be, db, key, idl );
 395
 396                         /* store the first id block */
 397                         kstr = (char *) ch_malloc( key.dsize + CONT_SIZE );
 398                         sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 399                                 ID_BLOCK_ID(tmp, 0), key.dptr );
 400
 401                         k2.dptr = kstr;
 402                         k2.dsize = strlen( kstr ) + 1;
 403                         rc = idl_store( be, db, k2, tmp );
 404
 405                         /* store the second id block */
 406                         sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 407                                 ID_BLOCK_ID(tmp2, 0), key.dptr );
 408                         k2.dptr = kstr;
 409                         k2.dsize = strlen( kstr ) + 1;
 410                         rc = idl_store( be, db, k2, tmp2 );
 411
 412                         free( kstr );
 413                         idl_free( tmp );
 414                         idl_free( tmp2 );
 415                         break;
 416                 }
 417
 418                 idl_free( idl );
 419                 return( rc );
 420         }
 421
 422         /*
 423          * this is an indirect block which points to other blocks.
 424          * we need to read in the block into which the id should be
 425          * inserted, then insert the id and store the block.  we might
 426          * have to split the block if it is full, which means we also
 427          * need to write a new "header" block.
 428          */
 429
 430         /* select the block to try inserting into *//* XXX linear search XXX */
 431         for ( i = 0; !ID_BLOCK_NOID(idl, i) && id > ID_BLOCK_ID(idl, i); i++ )
 432                 ;       /* NULL */
 433         if ( i != 0 ) {
 434                 i--;
 435                 first = 0;
 436         } else {
 437                 first = 1;
 438         }
 439
 440         /* get the block */
 441         kstr = (char *) ch_malloc( key.dsize + CONT_SIZE );
 442         sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 443                 ID_BLOCK_ID(idl, i), key.dptr );
 444         k2.dptr = kstr;
 445         k2.dsize = strlen( kstr ) + 1;
 446         if ( (tmp = idl_fetch_one( be, db, k2 )) == NULL ) {
 447                 Debug( LDAP_DEBUG_ANY, "nonexistent continuation block (%s)\n",
 448                     k2.dptr, 0, 0 );
 449                 free( kstr );
 450                 idl_free( idl );
 451                 return( -1 );
 452         }
 453
 454         /* insert the id */
 455         switch ( idl_insert( &tmp, id, db->dbc_maxids ) ) {
 456         case 0:         /* id inserted ok */
 457                 if ( (rc = idl_store( be, db, k2, tmp )) != 0 ) {
 458                         Debug( LDAP_DEBUG_ANY,
 459                             "idl_store of (%s) returns %d\n", k2.dptr, rc, 0 );
 460                 }
 461                 break;
 462
 463         case 1:         /* id inserted - first id in block has changed */
 464                 /*
 465                  * key for this block has changed, so we have to
 466                  * write the block under the new key, delete the
 467                  * old key block + update and write the indirect
 468                  * header block.
 469                  */
 470
 471                 rc = idl_change_first( be, db, key, idl, i, k2, tmp );
 472                 break;
 473
 474         case 2:         /* id not inserted - already there, do nothing */
 475                 rc = 0;
 476                 break;
 477
 478         case 3:         /* id not inserted - block is full */
 479                 /*
 480                  * first, see if it will fit in the next block,
 481                  * without splitting, unless we're trying to insert
 482                  * into the beginning of the first block.
 483                  */
 484
 485                 /* is there a next block? */
 486                 if ( !first && !ID_BLOCK_NOID(idl, i + 1) ) {
 487                         /* read it in */
 488                         sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 489                                 ID_BLOCK_ID(idl, i + 1), key.dptr );
 490                         k2.dptr = kstr;
 491                         k2.dsize = strlen( kstr ) + 1;
 492                         if ( (tmp2 = idl_fetch_one( be, db, k2 )) == NULL ) {
 493                                 Debug( LDAP_DEBUG_ANY,
 494                                     "idl_fetch_one (%s) returns NULL\n",
 495                                     k2.dptr, 0, 0 );
 496                                 /* split the original block */
 497                                 goto split;
 498                         }
 499
 500                         switch ( (rc = idl_insert( &tmp2, id,
 501                             db->dbc_maxids )) ) {
 502                         case 1:         /* id inserted first in block */
 503                                 rc = idl_change_first( be, db, key, idl,
 504                                     i + 1, k2, tmp2 );
 505                                 /* FALL */
 506
 507                         case 2:         /* id already there - how? */
 508                         case 0:         /* id inserted */
 509                                 if ( rc == 2 ) {
 510                                         Debug( LDAP_DEBUG_ANY,
 511                                             "id %ld already in next block\n",
 512                                             id, 0, 0 );
 513                                 }
 514                                 free( kstr );
 515                                 idl_free( tmp );
 516                                 idl_free( tmp2 );
 517                                 idl_free( idl );
 518                                 return( 0 );
 519
 520                         case 3:         /* split the original block */
 521                                 break;
 522                         }
 523
 524                         idl_free( tmp2 );
 525                 }
 526
 527 split:
 528                 /*
 529                  * must split the block, write both new blocks + update
 530                  * and write the indirect header block.
 531                  */
 532
 533                 rc = 0; /* optimistic */
 534
 535
 536                 /* count how many indirect blocks *//* XXX linear count XXX */
 537                 for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ )
 538                         ;       /* NULL */
 539
 540                 /* check it against all-id thresholed */
 541                 if ( j + 1 > db->dbc_maxindirect ) {
 542                         /*
 543                          * we've passed the all-id threshold, meaning
 544                          * that this set of blocks should be replaced
 545                          * by a single "all-id" block.  our job: delete
 546                          * all the indirect blocks, and replace the header
 547                          * block by an all-id block.
 548                          */
 549
 550                         /* delete all indirect blocks */
 551                         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ ) {
 552                                 sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 553                                         ID_BLOCK_ID(idl, j), key.dptr );
 554                                 k2.dptr = kstr;
 555                                 k2.dsize = strlen( kstr ) + 1;
 556
 557                                 rc = ldbm_cache_delete( db, k2 );
 558                         }
 559
 560                         /* store allid block in place of header block */
 561                         idl_free( idl );
 562                         idl = idl_allids( be );
 563                         rc = idl_store( be, db, key, idl );
 564
 565                         free( kstr );
 566                         idl_free( idl );
 567                         idl_free( tmp );
 568                         return( rc );
 569                 }
 570
 571                 idl_split_block( tmp, id, &tmp2, &tmp3 );
 572                 idl_free( tmp );
 573
 574                 /* create a new updated indirect header block */
 575                 tmp = idl_alloc( ID_BLOCK_NMAX(idl) + 1 );
 576                 ID_BLOCK_NIDS(tmp) = ID_BLOCK_INDIRECT_VALUE;
 577                 /* everything up to the split block */
 578                 SAFEMEMCPY(
 579                         (char *) &ID_BLOCK_ID(tmp, 0),
 580                         (char *) &ID_BLOCK_ID(idl, 0),
 581                     i * sizeof(ID) );
 582                 /* the two new blocks */
 583                 ID_BLOCK_ID(tmp, i) = ID_BLOCK_ID(tmp2, 0);
 584                 ID_BLOCK_ID(tmp, i + 1) = ID_BLOCK_ID(tmp3, 0);
 585                 /* everything after the split block */
 586                 SAFEMEMCPY(
 587                         (char *) &ID_BLOCK_ID(tmp, i + 2),
 588                         (char *) &ID_BLOCK_ID(idl, i + 1),
 589                         (ID_BLOCK_NMAX(idl) - i - 1) * sizeof(ID) );
 590
 591                 /* store the header block */
 592                 rc = idl_store( be, db, key, tmp );
 593
 594                 /* store the first id block */
 595                 sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 596                         ID_BLOCK_ID(tmp2, 0), key.dptr );
 597                 k2.dptr = kstr;
 598                 k2.dsize = strlen( kstr ) + 1;
 599                 rc = idl_store( be, db, k2, tmp2 );
 600
 601                 /* store the second id block */
 602                 sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 603                         ID_BLOCK_ID(tmp3, 0), key.dptr );
 604                 k2.dptr = kstr;
 605                 k2.dsize = strlen( kstr ) + 1;
 606                 rc = idl_store( be, db, k2, tmp3 );
 607
 608                 idl_free( tmp2 );
 609                 idl_free( tmp3 );
 610                 break;
 611         }
 612
 613         free( kstr );
 614         idl_free( tmp );
 615         idl_free( idl );
 616         return( rc );
 617 }
 618
 619
 620 /*
 621  * idl_insert - insert an id into an id list.
 622  *
 623  *      returns
 624  *              0       id inserted
 625  *              1       id inserted, first id in block has changed
 626  *              2       id not inserted, already there
 627  *              3       id not inserted, block must be split
 628  */
 629 int
 630 idl_insert( ID_BLOCK **idl, ID id, unsigned int maxids )
 631 {
 632         unsigned int    i;
 633
 634         if ( ID_BLOCK_ALLIDS( *idl ) ) {
 635                 return( 2 );    /* already there */
 636         }
 637
 638         /* is it already there? *//* XXX linear search XXX */
 639         for ( i = 0; i < ID_BLOCK_NIDS(*idl) && id > ID_BLOCK_ID(*idl, i); i++ ) {
 640                 ;       /* NULL */
 641         }
 642         if ( i < ID_BLOCK_NIDS(*idl) && ID_BLOCK_ID(*idl, i) == id ) {
 643                 return( 2 );    /* already there */
 644         }
 645
 646         /* do we need to make room for it? */
 647         if ( ID_BLOCK_NIDS(*idl) == ID_BLOCK_NMAX(*idl) ) {
 648                 /* make room or indicate block needs splitting */
 649                 if ( ID_BLOCK_NMAX(*idl) >= maxids ) {
 650                         return( 3 );    /* block needs splitting */
 651                 }
 652
 653                 ID_BLOCK_NMAX(*idl) *= 2;
 654                 if ( ID_BLOCK_NMAX(*idl) > maxids ) {
 655                         ID_BLOCK_NMAX(*idl) = maxids;
 656                 }
 657                 *idl = (ID_BLOCK *) ch_realloc( (char *) *idl,
 658                     (ID_BLOCK_NMAX(*idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
 659         }
 660
 661         /* make a slot for the new id */
 662         SAFEMEMCPY( &ID_BLOCK_ID(*idl, i+1), &ID_BLOCK_ID(*idl, i),
 663                     (ID_BLOCK_NIDS(*idl) - i) * sizeof(ID) );
 664
 665         ID_BLOCK_ID(*idl, i) = id;
 666         ID_BLOCK_NIDS(*idl)++;
 667         (void) memset(
 668                 (char *) &ID_BLOCK_ID((*idl), ID_BLOCK_NIDS(*idl)),
 669                 '\0',
 670             (ID_BLOCK_NMAX(*idl) - ID_BLOCK_NIDS(*idl)) * sizeof(ID) );
 671
 672         return( i == 0 ? 1 : 0 );       /* inserted - first id changed or not */
 673 }
 674
 675
 676 int
 677 idl_delete_key (
 678         Backend         *be,
 679         DBCache  *db,
 680         Datum           key,
 681         ID              id
 682 )
 683 {
 684         Datum  data;
 685         ID_BLOCK *idl;
 686         unsigned i;
 687         int j, nids;
 688         char    *kstr;
 689
 690         if ( (idl = idl_fetch_one( be, db, key ) ) == NULL )
 691         {
 692                 /* It wasn't found.  Hmm... */
 693                 return -1;
 694         }
 695
 696         if ( ID_BLOCK_ALLIDS( idl ) ) {
 697                 idl_free( idl );
 698                 return 0;
 699         }
 700
 701         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
 702                 for ( i=0; i < ID_BLOCK_NIDS(idl); i++ ) {
 703                         if ( ID_BLOCK_ID(idl, i) == id ) {
 704                                 if( --ID_BLOCK_NIDS(idl) == 0 ) {
 705                                         ldbm_cache_delete( db, key );
 706
 707                                 } else {
 708                                         SAFEMEMCPY (
 709                                                 &ID_BLOCK_ID(idl, i),
 710                                                 &ID_BLOCK_ID(idl, i+1),
 711                                                 (ID_BLOCK_NIDS(idl)-i) * sizeof(ID) );
 712
 713                                         ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)) = NOID;
 714
 715                                         idl_store( be, db, key, idl );
 716                                 }
 717
 718                                 idl_free( idl );
 719                                 return 0;
 720                         }
 721                         /*  We didn't find the ID.  Hmmm... */
 722                 }
 723                 idl_free( idl );
 724                 return -1;
 725         }
 726
 727         /* We have to go through an indirect block and find the ID
 728            in the list of IDL's
 729            */
 730         for ( nids = 0; !ID_BLOCK_NOID(idl, nids); nids++ )
 731                 ;       /* NULL */
 732         kstr = (char *) ch_malloc( key.dsize + CONT_SIZE );
 733
 734         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ )
 735         {
 736                 ID_BLOCK *tmp;
 737                 ldbm_datum_init( data );
 738                 sprintf( kstr, "%c%ld%s", CONT_PREFIX,
 739                         ID_BLOCK_ID(idl, j), key.dptr );
 740                 data.dptr = kstr;
 741                 data.dsize = strlen( kstr ) + 1;
 742
 743                 if ( (tmp = idl_fetch_one( be, db, data )) == NULL ) {
 744                         Debug( LDAP_DEBUG_ANY,
 745                             "idl_fetch of (%s) returns NULL\n", data.dptr, 0, 0 );
 746                         continue;
 747                 }
 748                 /*
 749                    Now try to find the ID in tmp
 750                 */
 751                 for ( i=0; i < ID_BLOCK_NIDS(tmp); i++ )
 752                 {
 753                         if ( ID_BLOCK_ID(tmp, i) == id )
 754                         {
 755                                 SAFEMEMCPY(
 756                                         &ID_BLOCK_ID(tmp, i),
 757                                         &ID_BLOCK_ID(tmp, i+1),
 758                                         (ID_BLOCK_NIDS(tmp)-(i+1)) * sizeof(ID));
 759                                 ID_BLOCK_ID(tmp, ID_BLOCK_NIDS(tmp)-1 ) = NOID;
 760                                 ID_BLOCK_NIDS(tmp)--;
 761
 762                                 if ( ID_BLOCK_NIDS(tmp) ) {
 763                                         idl_store ( be, db, data, tmp );
 764
 765                                 } else {
 766                                         ldbm_cache_delete( db, data );
 767                                         SAFEMEMCPY(
 768                                                 &ID_BLOCK_ID(idl, j),
 769                                                 &ID_BLOCK_ID(idl, j+1),
 770                                                 (nids-(j+1)) * sizeof(ID));
 771                                         ID_BLOCK_ID(idl, nids-1) = NOID;
 772                                         nids--;
 773                                         if ( ! nids )
 774                                                 ldbm_cache_delete( db, key );
 775                                         else
 776                                                 idl_store( be, db, key, idl );
 777                                 }
 778                                 idl_free( tmp );
 779                                 free( kstr );
 780                                 idl_free( idl );
 781                                 return 0;
 782                         }
 783                 }
 784                 idl_free( tmp );
 785         }
 786         free( kstr );
 787         idl_free( idl );
 788         return -1;
 789 }
 790
 791
 792 /* return a duplicate of a single ID_BLOCK */
 793 static ID_BLOCK *
 794 idl_dup( ID_BLOCK *idl )
 795 {
 796         ID_BLOCK        *new;
 797
 798         if ( idl == NULL ) {
 799                 return( NULL );
 800         }
 801
 802         new = idl_alloc( ID_BLOCK_NMAX(idl) );
 803
 804         SAFEMEMCPY(
 805                 (char *) new,
 806                 (char *) idl,
 807                 (ID_BLOCK_NMAX(idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
 808
 809         return( new );
 810 }
 811
 812
 813 /* return the smaller ID_BLOCK */
 814 static ID_BLOCK *
 815 idl_min( ID_BLOCK *a, ID_BLOCK *b )
 816 {
 817         return( ID_BLOCK_NIDS(a) > ID_BLOCK_NIDS(b) ? b : a );
 818 }
 819
 820
 821 /*
 822  * idl_intersection - return a intersection b
 823  */
 824 ID_BLOCK *
 825 idl_intersection(
 826     Backend     *be,
 827     ID_BLOCK    *a,
 828     ID_BLOCK    *b
 829 )
 830 {
 831         unsigned int    ai, bi, ni;
 832         ID_BLOCK                *n;
 833
 834         if ( a == NULL || b == NULL ) {
 835                 return( NULL );
 836         }
 837         if ( ID_BLOCK_ALLIDS( a ) ) {
 838                 return( idl_dup( b ) );
 839         }
 840         if ( ID_BLOCK_ALLIDS( b ) ) {
 841                 return( idl_dup( a ) );
 842         }
 843
 844         n = idl_dup( idl_min( a, b ) );
 845
 846         for ( ni = 0, ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
 847                 for ( ;
 848                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
 849                         bi++ )
 850                 {
 851                         ;       /* NULL */
 852                 }
 853
 854                 if ( bi == ID_BLOCK_NIDS(b) ) {
 855                         break;
 856                 }
 857
 858                 if ( ID_BLOCK_ID(b, bi) == ID_BLOCK_ID(a, ai) ) {
 859                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 860                 }
 861         }
 862
 863         if ( ni == 0 ) {
 864                 idl_free( n );
 865                 return( NULL );
 866         }
 867         ID_BLOCK_NIDS(n) = ni;
 868
 869         return( n );
 870 }
 871
 872
 873 /*
 874  * idl_union - return a union b
 875  */
 876 ID_BLOCK *
 877 idl_union(
 878     Backend     *be,
 879     ID_BLOCK    *a,
 880     ID_BLOCK    *b
 881 )
 882 {
 883         unsigned int    ai, bi, ni;
 884         ID_BLOCK                *n;
 885
 886         if ( a == NULL ) {
 887                 return( idl_dup( b ) );
 888         }
 889         if ( b == NULL ) {
 890                 return( idl_dup( a ) );
 891         }
 892         if ( ID_BLOCK_ALLIDS( a ) || ID_BLOCK_ALLIDS( b ) ) {
 893                 return( idl_allids( be ) );
 894         }
 895
 896         if ( ID_BLOCK_NIDS(b) < ID_BLOCK_NIDS(a) ) {
 897                 n = a;
 898                 a = b;
 899                 b = n;
 900         }
 901
 902         n = idl_alloc( ID_BLOCK_NIDS(a) + ID_BLOCK_NIDS(b) );
 903
 904         for ( ni = 0, ai = 0, bi = 0;
 905                 ai < ID_BLOCK_NIDS(a) && bi < ID_BLOCK_NIDS(b);
 906                 )
 907         {
 908                 if ( ID_BLOCK_ID(a, ai) < ID_BLOCK_ID(b, bi) ) {
 909                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai++);
 910
 911                 } else if ( ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai) ) {
 912                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi++);
 913
 914                 } else {
 915                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 916                         ai++, bi++;
 917                 }
 918         }
 919
 920         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
 921                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 922         }
 923         for ( ; bi < ID_BLOCK_NIDS(b); bi++ ) {
 924                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi);
 925         }
 926         ID_BLOCK_NIDS(n) = ni;
 927
 928         return( n );
 929 }
 930
 931
 932 /*
 933  * idl_notin - return a intersection ~b (or a minus b)
 934  */
 935 ID_BLOCK *
 936 idl_notin(
 937     Backend     *be,
 938     ID_BLOCK    *a,
 939     ID_BLOCK    *b
 940 )
 941 {
 942         unsigned int    ni, ai, bi;
 943         ID_BLOCK                *n;
 944
 945         if ( a == NULL ) {
 946                 return( NULL );
 947         }
 948         if ( b == NULL || ID_BLOCK_ALLIDS( b )) {
 949                 return( idl_dup( a ) );
 950         }
 951
 952         if ( ID_BLOCK_ALLIDS( a ) ) {
 953                 n = idl_alloc( SLAPD_LDBM_MIN_MAXIDS );
 954                 ni = 0;
 955
 956                 for ( ai = 1, bi = 0;
 957                         ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n) && bi < ID_BLOCK_NMAX(b);
 958                         ai++ )
 959                 {
 960                         if ( ID_BLOCK_ID(b, bi) == ai ) {
 961                                 bi++;
 962                         } else {
 963                                 ID_BLOCK_ID(n, ni++) = ai;
 964                         }
 965                 }
 966
 967                 for ( ; ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n); ai++ ) {
 968                         ID_BLOCK_ID(n, ni++) = ai;
 969                 }
 970
 971                 if ( ni == ID_BLOCK_NMAX(n) ) {
 972                         idl_free( n );
 973                         return( idl_allids( be ) );
 974                 } else {
 975                         ID_BLOCK_NIDS(n) = ni;
 976                         return( n );
 977                 }
 978         }
 979
 980         n = idl_dup( a );
 981
 982         ni = 0;
 983         for ( ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
 984                 for ( ;
 985                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
 986                     bi++ )
 987                 {
 988                         ;       /* NULL */
 989                 }
 990
 991                 if ( bi == ID_BLOCK_NIDS(b) ) {
 992                         break;
 993                 }
 994
 995                 if ( ID_BLOCK_ID(b, bi) != ID_BLOCK_ID(a, ai) ) {
 996                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
 997                 }
 998         }
 999
1000         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
1001                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
1002         }
1003         ID_BLOCK_NIDS(n) = ni;
1004
1005         return( n );
1006 }
1007
1008 /*      return the first ID in the block
1009  *      if ALLIDS block
1010  *              NIDS > 1 return 1
1011  *              otherwise return NOID
1012  *      otherwise return first ID
1013  *
1014  *      cursor is set to 1
1015  */
1016 ID
1017 idl_firstid( ID_BLOCK *idl, ID *cursor )
1018 {
1019         *cursor = 1;
1020
1021         if ( idl == NULL || ID_BLOCK_NIDS(idl) == 0 ) {
1022                 return( NOID );
1023         }
1024
1025         if ( ID_BLOCK_ALLIDS( idl ) ) {
1026                 return( ID_BLOCK_NIDS(idl) > 1 ? 1 : NOID );
1027         }
1028
1029         return( ID_BLOCK_ID(idl, 0) );
1030 }
1031
1032 /*      return next ID
1033  *      if ALLIDS block, cursor is id.
1034  *              increment id
1035  *              if id < NIDS return id
1036  *              otherwise NOID.
1037  *      otherwise cursor is index into block
1038  *              if index < nids
1039  *                      return id at index then increment
1040  */
1041 ID
1042 idl_nextid( ID_BLOCK *idl, ID *cursor )
1043 {
1044         if ( ID_BLOCK_ALLIDS( idl ) ) {
1045                 if( ++(*cursor) < ID_BLOCK_NIDS(idl) ) {
1046                         return *cursor;
1047                 } else {
1048                         return NOID;
1049                 }
1050         }
1051
1052         if ( *cursor < ID_BLOCK_NIDS(idl) ) {
1053                 return( ID_BLOCK_ID(idl, (*cursor)++) );
1054         }
1055
1056         return( NOID );
1057 }