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