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

   1 /* idl.c - ldap id list handling routines */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2000-2007 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  12  * A copy of this license is available in the file LICENSE in the
  13  * top-level directory of the distribution or, alternatively, at
  14  * <http://www.OpenLDAP.org/license.html>.
  15  */
  16
  17 #include "portable.h"
  18
  19 #include <stdio.h>
  20 #include <ac/string.h>
  21
  22 #include "back-bdb.h"
  23 #include "idl.h"
  24
  25 #define IDL_MAX(x,y)    ( x > y ? x : y )
  26 #define IDL_MIN(x,y)    ( x < y ? x : y )
  27
  28 #define IDL_CMP(x,y)    ( x < y ? -1 : ( x > y ? 1 : 0 ) )
  29
  30 #define IDL_LRU_DELETE( bdb, e ) do {                                   \
  31         if ( e == bdb->bi_idl_lru_head ) bdb->bi_idl_lru_head = e->idl_lru_next; \
  32         if ( e == bdb->bi_idl_lru_tail ) bdb->bi_idl_lru_tail = e->idl_lru_prev; \
  33         e->idl_lru_next->idl_lru_prev = e->idl_lru_prev; \
  34         e->idl_lru_prev->idl_lru_next = e->idl_lru_next; \
  35 } while ( 0 )
  36
  37 static int
  38 bdb_idl_entry_cmp( const void *v_idl1, const void *v_idl2 )
  39 {
  40         const bdb_idl_cache_entry_t *idl1 = v_idl1, *idl2 = v_idl2;
  41         int rc;
  42
  43         if ((rc = SLAP_PTRCMP( idl1->db, idl2->db ))) return rc;
  44         if ((rc = idl1->kstr.bv_len - idl2->kstr.bv_len )) return rc;
  45         return ( memcmp ( idl1->kstr.bv_val, idl2->kstr.bv_val , idl1->kstr.bv_len ) );
  46 }
  47
  48 #if IDL_DEBUG > 0
  49 static void idl_check( ID *ids )
  50 {
  51         if( BDB_IDL_IS_RANGE( ids ) ) {
  52                 assert( BDB_IDL_RANGE_FIRST(ids) <= BDB_IDL_RANGE_LAST(ids) );
  53         } else {
  54                 ID i;
  55                 for( i=1; i < ids[0]; i++ ) {
  56                         assert( ids[i+1] > ids[i] );
  57                 }
  58         }
  59 }
  60
  61 #if IDL_DEBUG > 1
  62 static void idl_dump( ID *ids )
  63 {
  64         if( BDB_IDL_IS_RANGE( ids ) ) {
  65                 Debug( LDAP_DEBUG_ANY,
  66                         "IDL: range ( %ld - %ld )\n",
  67                         (long) BDB_IDL_RANGE_FIRST( ids ),
  68                         (long) BDB_IDL_RANGE_LAST( ids ) );
  69
  70         } else {
  71                 ID i;
  72                 Debug( LDAP_DEBUG_ANY, "IDL: size %ld", (long) ids[0], 0, 0 );
  73
  74                 for( i=1; i<=ids[0]; i++ ) {
  75                         if( i % 16 == 1 ) {
  76                                 Debug( LDAP_DEBUG_ANY, "\n", 0, 0, 0 );
  77                         }
  78                         Debug( LDAP_DEBUG_ANY, "  %02lx", (long) ids[i], 0, 0 );
  79                 }
  80
  81                 Debug( LDAP_DEBUG_ANY, "\n", 0, 0, 0 );
  82         }
  83
  84         idl_check( ids );
  85 }
  86 #endif /* IDL_DEBUG > 1 */
  87 #endif /* IDL_DEBUG > 0 */
  88
  89 unsigned bdb_idl_search( ID *ids, ID id )
  90 {
  91 #define IDL_BINARY_SEARCH 1
  92 #ifdef IDL_BINARY_SEARCH
  93         /*
  94          * binary search of id in ids
  95          * if found, returns position of id
  96          * if not found, returns first postion greater than id
  97          */
  98         unsigned base = 0;
  99         unsigned cursor = 0;
 100         int val = 0;
 101         unsigned n = ids[0];
 102
 103 #if IDL_DEBUG > 0
 104         idl_check( ids );
 105 #endif
 106
 107         while( 0 < n ) {
 108                 int pivot = n >> 1;
 109                 cursor = base + pivot;
 110                 val = IDL_CMP( id, ids[cursor + 1] );
 111
 112                 if( val < 0 ) {
 113                         n = pivot;
 114
 115                 } else if ( val > 0 ) {
 116                         base = cursor + 1;
 117                         n -= pivot + 1;
 118
 119                 } else {
 120                         return cursor + 1;
 121                 }
 122         }
 123
 124         if( val > 0 ) {
 125                 return cursor + 2;
 126         } else {
 127                 return cursor + 1;
 128         }
 129
 130 #else
 131         /* (reverse) linear search */
 132         int i;
 133
 134 #if IDL_DEBUG > 0
 135         idl_check( ids );
 136 #endif
 137
 138         for( i=ids[0]; i; i-- ) {
 139                 if( id > ids[i] ) {
 140                         break;
 141                 }
 142         }
 143
 144         return i+1;
 145 #endif
 146 }
 147
 148 int bdb_idl_insert( ID *ids, ID id )
 149 {
 150         unsigned x;
 151
 152 #if IDL_DEBUG > 1
 153         Debug( LDAP_DEBUG_ANY, "insert: %04lx at %d\n", (long) id, x, 0 );
 154         idl_dump( ids );
 155 #elif IDL_DEBUG > 0
 156         idl_check( ids );
 157 #endif
 158
 159         if (BDB_IDL_IS_RANGE( ids )) {
 160                 /* if already in range, treat as a dup */
 161                 if (id >= BDB_IDL_FIRST(ids) && id <= BDB_IDL_LAST(ids))
 162                         return -1;
 163                 if (id < BDB_IDL_FIRST(ids))
 164                         ids[1] = id;
 165                 else if (id > BDB_IDL_LAST(ids))
 166                         ids[2] = id;
 167                 return 0;
 168         }
 169
 170         x = bdb_idl_search( ids, id );
 171         assert( x > 0 );
 172
 173         if( x < 1 ) {
 174                 /* internal error */
 175                 return -2;
 176         }
 177
 178         if ( x <= ids[0] && ids[x] == id ) {
 179                 /* duplicate */
 180                 return -1;
 181         }
 182
 183         if ( ++ids[0] >= BDB_IDL_DB_MAX ) {
 184                 if( id < ids[1] ) {
 185                         ids[1] = id;
 186                         ids[2] = ids[ids[0]-1];
 187                 } else if ( ids[ids[0]-1] < id ) {
 188                         ids[2] = id;
 189                 } else {
 190                         ids[2] = ids[ids[0]-1];
 191                 }
 192                 ids[0] = NOID;
 193
 194         } else {
 195                 /* insert id */
 196                 AC_MEMCPY( &ids[x+1], &ids[x], (ids[0]-x) * sizeof(ID) );
 197                 ids[x] = id;
 198         }
 199
 200 #if IDL_DEBUG > 1
 201         idl_dump( ids );
 202 #elif IDL_DEBUG > 0
 203         idl_check( ids );
 204 #endif
 205
 206         return 0;
 207 }
 208
 209 static int bdb_idl_delete( ID *ids, ID id )
 210 {
 211         unsigned x;
 212
 213 #if IDL_DEBUG > 1
 214         Debug( LDAP_DEBUG_ANY, "delete: %04lx at %d\n", (long) id, x, 0 );
 215         idl_dump( ids );
 216 #elif IDL_DEBUG > 0
 217         idl_check( ids );
 218 #endif
 219
 220         if (BDB_IDL_IS_RANGE( ids )) {
 221                 /* If deleting a range boundary, adjust */
 222                 if ( ids[1] == id )
 223                         ids[1]++;
 224                 else if ( ids[2] == id )
 225                         ids[2]--;
 226                 /* deleting from inside a range is a no-op */
 227
 228                 /* If the range has collapsed, re-adjust */
 229                 if ( ids[1] > ids[2] )
 230                         ids[0] = 0;
 231                 else if ( ids[1] == ids[2] )
 232                         ids[1] = 1;
 233                 return 0;
 234         }
 235
 236         x = bdb_idl_search( ids, id );
 237         assert( x > 0 );
 238
 239         if( x <= 0 ) {
 240                 /* internal error */
 241                 return -2;
 242         }
 243
 244         if( x > ids[0] || ids[x] != id ) {
 245                 /* not found */
 246                 return -1;
 247
 248         } else if ( --ids[0] == 0 ) {
 249                 if( x != 1 ) {
 250                         return -3;
 251                 }
 252
 253         } else {
 254                 AC_MEMCPY( &ids[x], &ids[x+1], (1+ids[0]-x) * sizeof(ID) );
 255         }
 256
 257 #if IDL_DEBUG > 1
 258         idl_dump( ids );
 259 #elif IDL_DEBUG > 0
 260         idl_check( ids );
 261 #endif
 262
 263         return 0;
 264 }
 265
 266 static char *
 267 bdb_show_key(
 268         DBT             *key,
 269         char            *buf )
 270 {
 271         if ( key->size == 4 /* LUTIL_HASH_BYTES */ ) {
 272                 unsigned char *c = key->data;
 273                 sprintf( buf, "[%02x%02x%02x%02x]", c[0], c[1], c[2], c[3] );
 274                 return buf;
 275         } else {
 276                 return key->data;
 277         }
 278 }
 279
 280 /* Find a db/key pair in the IDL cache. If ids is non-NULL,
 281  * copy the cached IDL into it, otherwise just return the status.
 282  */
 283 int
 284 bdb_idl_cache_get(
 285         struct bdb_info *bdb,
 286         DB                      *db,
 287         DBT                     *key,
 288         ID                      *ids )
 289 {
 290         bdb_idl_cache_entry_t idl_tmp;
 291         bdb_idl_cache_entry_t *matched_idl_entry;
 292         int rc = LDAP_NO_SUCH_OBJECT;
 293
 294         DBT2bv( key, &idl_tmp.kstr );
 295         idl_tmp.db = db;
 296         ldap_pvt_thread_rdwr_rlock( &bdb->bi_idl_tree_rwlock );
 297         matched_idl_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 298                                       bdb_idl_entry_cmp );
 299         if ( matched_idl_entry != NULL ) {
 300                 if ( matched_idl_entry->idl && ids )
 301                         BDB_IDL_CPY( ids, matched_idl_entry->idl );
 302                 matched_idl_entry->idl_flags |= CACHE_ENTRY_REFERENCED;
 303                 if ( matched_idl_entry->idl )
 304                         rc = LDAP_SUCCESS;
 305                 else
 306                         rc = DB_NOTFOUND;
 307         }
 308         ldap_pvt_thread_rdwr_runlock( &bdb->bi_idl_tree_rwlock );
 309
 310         return rc;
 311 }
 312
 313 void
 314 bdb_idl_cache_put(
 315         struct bdb_info *bdb,
 316         DB                      *db,
 317         DBT                     *key,
 318         ID                      *ids,
 319         int                     rc )
 320 {
 321         bdb_idl_cache_entry_t idl_tmp;
 322         bdb_idl_cache_entry_t *ee, *eprev;
 323
 324         if ( rc == DB_NOTFOUND || BDB_IDL_IS_ZERO( ids ))
 325                 return;
 326
 327         DBT2bv( key, &idl_tmp.kstr );
 328
 329         ee = (bdb_idl_cache_entry_t *) ch_malloc(
 330                 sizeof( bdb_idl_cache_entry_t ) );
 331         ee->db = db;
 332         ee->idl = (ID*) ch_malloc( BDB_IDL_SIZEOF ( ids ) );
 333         BDB_IDL_CPY( ee->idl, ids );
 334
 335         ee->idl_lru_prev = NULL;
 336         ee->idl_lru_next = NULL;
 337         ee->idl_flags = 0;
 338         ber_dupbv( &ee->kstr, &idl_tmp.kstr );
 339         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 340         if ( avl_insert( &bdb->bi_idl_tree, (caddr_t) ee,
 341                 bdb_idl_entry_cmp, avl_dup_error ))
 342         {
 343                 ch_free( ee->kstr.bv_val );
 344                 ch_free( ee->idl );
 345                 ch_free( ee );
 346                 ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 347                 return;
 348         }
 349         ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 350         /* LRU_ADD */
 351         if ( bdb->bi_idl_lru_head ) {
 352                 ee->idl_lru_next = bdb->bi_idl_lru_head;
 353                 ee->idl_lru_prev = bdb->bi_idl_lru_head->idl_lru_prev;
 354                 bdb->bi_idl_lru_head->idl_lru_prev->idl_lru_next = ee;
 355                 bdb->bi_idl_lru_head->idl_lru_prev = ee;
 356         } else {
 357                 ee->idl_lru_next = ee->idl_lru_prev = ee;
 358                 bdb->bi_idl_lru_tail = ee;
 359         }
 360         bdb->bi_idl_lru_head = ee;
 361
 362         if ( ++bdb->bi_idl_cache_size > bdb->bi_idl_cache_max_size ) {
 363                 int i;
 364                 ee = bdb->bi_idl_lru_tail;
 365                 for ( i = 0; i < 10; i++, ee = eprev ) {
 366                         eprev = ee->idl_lru_prev;
 367                         if ( ee->idl_flags & CACHE_ENTRY_REFERENCED ) {
 368                                 ee->idl_flags ^= CACHE_ENTRY_REFERENCED;
 369                                 continue;
 370                         }
 371                         if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) ee,
 372                                     bdb_idl_entry_cmp ) == NULL ) {
 373                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_put: "
 374                                         "AVL delete failed\n",
 375                                         0, 0, 0 );
 376                         }
 377                         IDL_LRU_DELETE( bdb, ee );
 378                         i++;
 379                         --bdb->bi_idl_cache_size;
 380                         ch_free( ee->kstr.bv_val );
 381                         ch_free( ee->idl );
 382                         ch_free( ee );
 383                 }
 384                 bdb->bi_idl_lru_tail = eprev;
 385         }
 386         ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 387         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 388 }
 389
 390 void
 391 bdb_idl_cache_del(
 392         struct bdb_info *bdb,
 393         DB                      *db,
 394         DBT                     *key )
 395 {
 396         bdb_idl_cache_entry_t *matched_idl_entry, idl_tmp;
 397         DBT2bv( key, &idl_tmp.kstr );
 398         idl_tmp.db = db;
 399         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 400         matched_idl_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 401                                       bdb_idl_entry_cmp );
 402         if ( matched_idl_entry != NULL ) {
 403                 if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) matched_idl_entry,
 404                                     bdb_idl_entry_cmp ) == NULL ) {
 405                         Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_del: "
 406                                 "AVL delete failed\n",
 407                                 0, 0, 0 );
 408                 }
 409                 --bdb->bi_idl_cache_size;
 410                 ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 411                 IDL_LRU_DELETE( bdb, matched_idl_entry );
 412                 ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 413                 free( matched_idl_entry->kstr.bv_val );
 414                 if ( matched_idl_entry->idl )
 415                         free( matched_idl_entry->idl );
 416                 free( matched_idl_entry );
 417         }
 418         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 419 }
 420
 421 void
 422 bdb_idl_cache_add_id(
 423         struct bdb_info *bdb,
 424         DB                      *db,
 425         DBT                     *key,
 426         ID                      id )
 427 {
 428         bdb_idl_cache_entry_t *cache_entry, idl_tmp;
 429         DBT2bv( key, &idl_tmp.kstr );
 430         idl_tmp.db = db;
 431         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 432         cache_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 433                                       bdb_idl_entry_cmp );
 434         if ( cache_entry != NULL ) {
 435                 if ( !BDB_IDL_IS_RANGE( cache_entry->idl ) &&
 436                         cache_entry->idl[0] < BDB_IDL_DB_MAX ) {
 437                         size_t s = BDB_IDL_SIZEOF( cache_entry->idl ) + sizeof(ID);
 438                         cache_entry->idl = ch_realloc( cache_entry->idl, s );
 439                 }
 440                 bdb_idl_insert( cache_entry->idl, id );
 441         }
 442         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 443 }
 444
 445 void
 446 bdb_idl_cache_del_id(
 447         struct bdb_info *bdb,
 448         DB                      *db,
 449         DBT                     *key,
 450         ID                      id )
 451 {
 452         bdb_idl_cache_entry_t *cache_entry, idl_tmp;
 453         DBT2bv( key, &idl_tmp.kstr );
 454         idl_tmp.db = db;
 455         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 456         cache_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 457                                       bdb_idl_entry_cmp );
 458         if ( cache_entry != NULL ) {
 459                 bdb_idl_delete( cache_entry->idl, id );
 460                 if ( cache_entry->idl[0] == 0 ) {
 461                         if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) cache_entry,
 462                                                 bdb_idl_entry_cmp ) == NULL ) {
 463                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_del: "
 464                                         "AVL delete failed\n",
 465                                         0, 0, 0 );
 466                         }
 467                         --bdb->bi_idl_cache_size;
 468                         ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 469                         IDL_LRU_DELETE( bdb, cache_entry );
 470                         ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 471                         free( cache_entry->kstr.bv_val );
 472                         free( cache_entry->idl );
 473                         free( cache_entry );
 474                 }
 475         }
 476         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 477 }
 478
 479 int
 480 bdb_idl_fetch_key(
 481         BackendDB       *be,
 482         DB                      *db,
 483         BDB_LOCKER locker,
 484         DBT                     *key,
 485         ID                      *ids,
 486         DBC                     **saved_cursor,
 487         int                     get_flag )
 488 {
 489         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 490         int rc;
 491         DBT data, key2, *kptr;
 492         DBC *cursor;
 493         ID *i;
 494         void *ptr;
 495         size_t len;
 496         int rc2;
 497         int flags = bdb->bi_db_opflags | DB_MULTIPLE;
 498         int opflag;
 499
 500         /* If using BerkeleyDB 4.0, the buf must be large enough to
 501          * grab the entire IDL in one get(), otherwise BDB will leak
 502          * resources on subsequent get's.  We can safely call get()
 503          * twice - once for the data, and once to get the DB_NOTFOUND
 504          * result meaning there's no more data. See ITS#2040 for details.
 505          * This bug is fixed in BDB 4.1 so a smaller buffer will work if
 506          * stack space is too limited.
 507          *
 508          * configure now requires Berkeley DB 4.1.
 509          */
 510 #if DB_VERSION_FULL < 0x04010000
 511 #       define BDB_ENOUGH 5
 512 #else
 513         /* We sometimes test with tiny IDLs, and BDB always wants buffers
 514          * that are at least one page in size.
 515          */
 516 # if BDB_IDL_DB_SIZE < 4096
 517 #   define BDB_ENOUGH 2048
 518 # else
 519 #       define BDB_ENOUGH 1
 520 # endif
 521 #endif
 522         ID buf[BDB_IDL_DB_SIZE*BDB_ENOUGH];
 523
 524         char keybuf[16];
 525
 526         Debug( LDAP_DEBUG_ARGS,
 527                 "bdb_idl_fetch_key: %s\n",
 528                 bdb_show_key( key, keybuf ), 0, 0 );
 529
 530         assert( ids != NULL );
 531
 532         if ( saved_cursor && *saved_cursor ) {
 533                 opflag = DB_NEXT;
 534         } else if ( get_flag == LDAP_FILTER_GE ) {
 535                 opflag = DB_SET_RANGE;
 536         } else if ( get_flag == LDAP_FILTER_LE ) {
 537                 opflag = DB_FIRST;
 538         } else {
 539                 opflag = DB_SET;
 540         }
 541
 542         /* only non-range lookups can use the IDL cache */
 543         if ( bdb->bi_idl_cache_size && opflag == DB_SET ) {
 544                 rc = bdb_idl_cache_get( bdb, db, key, ids );
 545                 if ( rc != LDAP_NO_SUCH_OBJECT ) return rc;
 546         }
 547
 548         DBTzero( &data );
 549
 550         data.data = buf;
 551         data.ulen = sizeof(buf);
 552         data.flags = DB_DBT_USERMEM;
 553
 554         /* If we're not reusing an existing cursor, get a new one */
 555         if( opflag != DB_NEXT ) {
 556                 rc = db->cursor( db, NULL, &cursor, bdb->bi_db_opflags );
 557                 if( rc != 0 ) {
 558                         Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 559                                 "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 560                         return rc;
 561                 }
 562                 CURSOR_SETLOCKER( cursor, locker );
 563         } else {
 564                 cursor = *saved_cursor;
 565         }
 566
 567         /* If this is a LE lookup, save original key so we can determine
 568          * when to stop. If this is a GE lookup, save the key since it
 569          * will be overwritten.
 570          */
 571         if ( get_flag == LDAP_FILTER_LE || get_flag == LDAP_FILTER_GE ) {
 572                 DBTzero( &key2 );
 573                 key2.flags = DB_DBT_USERMEM;
 574                 key2.ulen = sizeof(keybuf);
 575                 key2.data = keybuf;
 576                 key2.size = key->size;
 577                 AC_MEMCPY( keybuf, key->data, key->size );
 578                 kptr = &key2;
 579         } else {
 580                 kptr = key;
 581         }
 582         len = key->size;
 583         rc = cursor->c_get( cursor, kptr, &data, flags | opflag );
 584
 585         /* skip presence key on range inequality lookups */
 586         while (rc == 0 && kptr->size != len) {
 587                 rc = cursor->c_get( cursor, kptr, &data, flags | DB_NEXT_NODUP );
 588         }
 589         /* If we're doing a LE compare and the new key is greater than
 590          * our search key, we're done
 591          */
 592         if (rc == 0 && get_flag == LDAP_FILTER_LE && memcmp( kptr->data,
 593                 key->data, key->size ) > 0 ) {
 594                 rc = DB_NOTFOUND;
 595         }
 596         if (rc == 0) {
 597                 i = ids;
 598                 while (rc == 0) {
 599                         u_int8_t *j;
 600
 601                         DB_MULTIPLE_INIT( ptr, &data );
 602                         while (ptr) {
 603                                 DB_MULTIPLE_NEXT(ptr, &data, j, len);
 604                                 if (j) {
 605                                         ++i;
 606                                         BDB_DISK2ID( j, i );
 607                                 }
 608                         }
 609                         rc = cursor->c_get( cursor, key, &data, flags | DB_NEXT_DUP );
 610                 }
 611                 if ( rc == DB_NOTFOUND ) rc = 0;
 612                 ids[0] = i - ids;
 613                 /* On disk, a range is denoted by 0 in the first element */
 614                 if (ids[1] == 0) {
 615                         if (ids[0] != BDB_IDL_RANGE_SIZE) {
 616                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 617                                         "range size mismatch: expected %d, got %ld\n",
 618                                         BDB_IDL_RANGE_SIZE, ids[0], 0 );
 619                                 cursor->c_close( cursor );
 620                                 return -1;
 621                         }
 622                         BDB_IDL_RANGE( ids, ids[2], ids[3] );
 623                 }
 624                 data.size = BDB_IDL_SIZEOF(ids);
 625         }
 626
 627         if ( saved_cursor && rc == 0 ) {
 628                 if ( !*saved_cursor )
 629                         *saved_cursor = cursor;
 630                 rc2 = 0;
 631         }
 632         else
 633                 rc2 = cursor->c_close( cursor );
 634         if (rc2) {
 635                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 636                         "close failed: %s (%d)\n", db_strerror(rc2), rc2, 0 );
 637                 return rc2;
 638         }
 639
 640         if( rc == DB_NOTFOUND ) {
 641                 return rc;
 642
 643         } else if( rc != 0 ) {
 644                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 645                         "get failed: %s (%d)\n",
 646                         db_strerror(rc), rc, 0 );
 647                 return rc;
 648
 649         } else if ( data.size == 0 || data.size % sizeof( ID ) ) {
 650                 /* size not multiple of ID size */
 651                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 652                         "odd size: expected %ld multiple, got %ld\n",
 653                         (long) sizeof( ID ), (long) data.size, 0 );
 654                 return -1;
 655
 656         } else if ( data.size != BDB_IDL_SIZEOF(ids) ) {
 657                 /* size mismatch */
 658                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 659                         "get size mismatch: expected %ld, got %ld\n",
 660                         (long) ((1 + ids[0]) * sizeof( ID )), (long) data.size, 0 );
 661                 return -1;
 662         }
 663
 664         if ( bdb->bi_idl_cache_max_size ) {
 665                 bdb_idl_cache_put( bdb, db, key, ids, rc );
 666         }
 667
 668         return rc;
 669 }
 670
 671
 672 int
 673 bdb_idl_insert_key(
 674         BackendDB       *be,
 675         DB                      *db,
 676         DB_TXN          *tid,
 677         DBT                     *key,
 678         ID                      id )
 679 {
 680         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 681         int     rc;
 682         DBT data;
 683         DBC *cursor;
 684         ID lo, hi, nlo, nhi, nid;
 685         char *err;
 686
 687         {
 688                 char buf[16];
 689                 Debug( LDAP_DEBUG_ARGS,
 690                         "bdb_idl_insert_key: %lx %s\n",
 691                         (long) id, bdb_show_key( key, buf ), 0 );
 692         }
 693
 694         assert( id != NOID );
 695
 696         if ( bdb->bi_idl_cache_size ) {
 697                 bdb_idl_cache_del( bdb, db, key );
 698         }
 699
 700         DBTzero( &data );
 701         data.size = sizeof( ID );
 702         data.ulen = data.size;
 703         data.flags = DB_DBT_USERMEM;
 704
 705         BDB_ID2DISK( id, &nid );
 706
 707         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 708         if ( rc != 0 ) {
 709                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 710                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 711                 return rc;
 712         }
 713         data.data = &nlo;
 714         /* Fetch the first data item for this key, to see if it
 715          * exists and if it's a range.
 716          */
 717         rc = cursor->c_get( cursor, key, &data, DB_SET );
 718         err = "c_get";
 719         if ( rc == 0 ) {
 720                 if ( nlo != 0 ) {
 721                         /* not a range, count the number of items */
 722                         db_recno_t count;
 723                         rc = cursor->c_count( cursor, &count, 0 );
 724                         if ( rc != 0 ) {
 725                                 err = "c_count";
 726                                 goto fail;
 727                         }
 728                         if ( count >= BDB_IDL_DB_MAX ) {
 729                         /* No room, convert to a range */
 730                                 DBT key2 = *key;
 731                                 db_recno_t i;
 732
 733                                 key2.dlen = key2.ulen;
 734                                 key2.flags |= DB_DBT_PARTIAL;
 735
 736                                 BDB_DISK2ID( &nlo, &lo );
 737                                 data.data = &nhi;
 738
 739                                 rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_NODUP );
 740                                 if ( rc != 0 && rc != DB_NOTFOUND ) {
 741                                         err = "c_get next_nodup";
 742                                         goto fail;
 743                                 }
 744                                 if ( rc == DB_NOTFOUND ) {
 745                                         rc = cursor->c_get( cursor, key, &data, DB_LAST );
 746                                         if ( rc != 0 ) {
 747                                                 err = "c_get last";
 748                                                 goto fail;
 749                                         }
 750                                 } else {
 751                                         rc = cursor->c_get( cursor, key, &data, DB_PREV );
 752                                         if ( rc != 0 ) {
 753                                                 err = "c_get prev";
 754                                                 goto fail;
 755                                         }
 756                                 }
 757                                 BDB_DISK2ID( &nhi, &hi );
 758                                 /* Update hi/lo if needed, then delete all the items
 759                                  * between lo and hi
 760                                  */
 761                                 if ( id < lo ) {
 762                                         lo = id;
 763                                         nlo = nid;
 764                                 } else if ( id > hi ) {
 765                                         hi = id;
 766                                         nhi = nid;
 767                                 }
 768                                 data.data = &nid;
 769                                 /* Don't fetch anything, just position cursor */
 770                                 data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 771                                 data.dlen = data.ulen = 0;
 772                                 rc = cursor->c_get( cursor, key, &data, DB_SET );
 773                                 if ( rc != 0 ) {
 774                                         err = "c_get 2";
 775                                         goto fail;
 776                                 }
 777                                 rc = cursor->c_del( cursor, 0 );
 778                                 if ( rc != 0 ) {
 779                                         err = "c_del range1";
 780                                         goto fail;
 781                                 }
 782                                 /* Delete all the records */
 783                                 for ( i=1; i<count; i++ ) {
 784                                         rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_DUP );
 785                                         if ( rc != 0 ) {
 786                                                 err = "c_get next_dup";
 787                                                 goto fail;
 788                                         }
 789                                         rc = cursor->c_del( cursor, 0 );
 790                                         if ( rc != 0 ) {
 791                                                 err = "c_del range";
 792                                                 goto fail;
 793                                         }
 794                                 }
 795                                 /* Store the range marker */
 796                                 data.size = data.ulen = sizeof(ID);
 797                                 data.flags = DB_DBT_USERMEM;
 798                                 nid = 0;
 799                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 800                                 if ( rc != 0 ) {
 801                                         err = "c_put range";
 802                                         goto fail;
 803                                 }
 804                                 nid = nlo;
 805                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 806                                 if ( rc != 0 ) {
 807                                         err = "c_put lo";
 808                                         goto fail;
 809                                 }
 810                                 nid = nhi;
 811                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 812                                 if ( rc != 0 ) {
 813                                         err = "c_put hi";
 814                                         goto fail;
 815                                 }
 816                         } else {
 817                         /* There's room, just store it */
 818                                 goto put1;
 819                         }
 820                 } else {
 821                         /* It's a range, see if we need to rewrite
 822                          * the boundaries
 823                          */
 824                         hi = id;
 825                         data.data = &nlo;
 826                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 827                         if ( rc != 0 ) {
 828                                 err = "c_get lo";
 829                                 goto fail;
 830                         }
 831                         BDB_DISK2ID( &nlo, &lo );
 832                         if ( id > lo ) {
 833                                 data.data = &nhi;
 834                                 rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 835                                 if ( rc != 0 ) {
 836                                         err = "c_get hi";
 837                                         goto fail;
 838                                 }
 839                                 BDB_DISK2ID( &nhi, &hi );
 840                         }
 841                         if ( id < lo || id > hi ) {
 842                                 /* Delete the current lo/hi */
 843                                 rc = cursor->c_del( cursor, 0 );
 844                                 if ( rc != 0 ) {
 845                                         err = "c_del";
 846                                         goto fail;
 847                                 }
 848                                 data.data = &nid;
 849                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 850                                 if ( rc != 0 ) {
 851                                         err = "c_put lo/hi";
 852                                         goto fail;
 853                                 }
 854                         }
 855                 }
 856         } else if ( rc == DB_NOTFOUND ) {
 857 put1:           data.data = &nid;
 858                 rc = cursor->c_put( cursor, key, &data, DB_NODUPDATA );
 859                 /* Don't worry if it's already there */
 860                 if ( rc != 0 && rc != DB_KEYEXIST ) {
 861                         err = "c_put id";
 862                         goto fail;
 863                 }
 864         } else {
 865                 /* initial c_get failed, nothing was done */
 866 fail:
 867                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 868                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
 869                 cursor->c_close( cursor );
 870                 return rc;
 871         }
 872         rc = cursor->c_close( cursor );
 873         if( rc != 0 ) {
 874                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 875                         "c_close failed: %s (%d)\n",
 876                         db_strerror(rc), rc, 0 );
 877         }
 878         return rc;
 879 }
 880
 881 int
 882 bdb_idl_delete_key(
 883         BackendDB       *be,
 884         DB                      *db,
 885         DB_TXN          *tid,
 886         DBT                     *key,
 887         ID                      id )
 888 {
 889         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 890         int     rc;
 891         DBT data;
 892         DBC *cursor;
 893         ID lo, hi, tmp, nid, nlo, nhi;
 894         char *err;
 895
 896         {
 897                 char buf[16];
 898                 Debug( LDAP_DEBUG_ARGS,
 899                         "bdb_idl_delete_key: %lx %s\n",
 900                         (long) id, bdb_show_key( key, buf ), 0 );
 901         }
 902         assert( id != NOID );
 903
 904         if ( bdb->bi_idl_cache_max_size ) {
 905                 bdb_idl_cache_del( bdb, db, key );
 906         }
 907
 908         BDB_ID2DISK( id, &nid );
 909
 910         DBTzero( &data );
 911         data.data = &tmp;
 912         data.size = sizeof( id );
 913         data.ulen = data.size;
 914         data.flags = DB_DBT_USERMEM;
 915
 916         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 917         if ( rc != 0 ) {
 918                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
 919                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 920                 return rc;
 921         }
 922         /* Fetch the first data item for this key, to see if it
 923          * exists and if it's a range.
 924          */
 925         rc = cursor->c_get( cursor, key, &data, DB_SET );
 926         err = "c_get";
 927         if ( rc == 0 ) {
 928                 if ( tmp != 0 ) {
 929                         /* Not a range, just delete it */
 930                         if (tmp != nid) {
 931                                 /* position to correct item */
 932                                 tmp = nid;
 933                                 rc = cursor->c_get( cursor, key, &data, DB_GET_BOTH );
 934                                 if ( rc != 0 ) {
 935                                         err = "c_get id";
 936                                         goto fail;
 937                                 }
 938                         }
 939                         rc = cursor->c_del( cursor, 0 );
 940                         if ( rc != 0 ) {
 941                                 err = "c_del id";
 942                                 goto fail;
 943                         }
 944                 } else {
 945                         /* It's a range, see if we need to rewrite
 946                          * the boundaries
 947                          */
 948                         data.data = &nlo;
 949                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 950                         if ( rc != 0 ) {
 951                                 err = "c_get lo";
 952                                 goto fail;
 953                         }
 954                         BDB_DISK2ID( &nlo, &lo );
 955                         data.data = &nhi;
 956                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 957                         if ( rc != 0 ) {
 958                                 err = "c_get hi";
 959                                 goto fail;
 960                         }
 961                         BDB_DISK2ID( &nhi, &hi );
 962                         if ( id == lo || id == hi ) {
 963                                 if ( id == lo ) {
 964                                         id++;
 965                                         lo = id;
 966                                 } else if ( id == hi ) {
 967                                         id--;
 968                                         hi = id;
 969                                 }
 970                                 if ( lo >= hi ) {
 971                                 /* The range has collapsed... */
 972                                         rc = db->del( db, tid, key, 0 );
 973                                         if ( rc != 0 ) {
 974                                                 err = "del";
 975                                                 goto fail;
 976                                         }
 977                                 } else {
 978                                         if ( id == lo ) {
 979                                                 /* reposition on lo slot */
 980                                                 data.data = &nlo;
 981                                                 cursor->c_get( cursor, key, &data, DB_PREV );
 982                                         }
 983                                         rc = cursor->c_del( cursor, 0 );
 984                                         if ( rc != 0 ) {
 985                                                 err = "c_del";
 986                                                 goto fail;
 987                                         }
 988                                 }
 989                                 if ( lo <= hi ) {
 990                                         BDB_ID2DISK( id, &nid );
 991                                         data.data = &nid;
 992                                         rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 993                                         if ( rc != 0 ) {
 994                                                 err = "c_put lo/hi";
 995                                                 goto fail;
 996                                         }
 997                                 }
 998                         }
 999                 }
1000         } else {
1001                 /* initial c_get failed, nothing was done */
1002 fail:
1003                 if ( rc != DB_NOTFOUND ) {
1004                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
1005                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
1006                 }
1007                 cursor->c_close( cursor );
1008                 return rc;
1009         }
1010         rc = cursor->c_close( cursor );
1011         if( rc != 0 ) {
1012                 Debug( LDAP_DEBUG_ANY,
1013                         "=> bdb_idl_delete_key: c_close failed: %s (%d)\n",
1014                         db_strerror(rc), rc, 0 );
1015         }
1016
1017         return rc;
1018 }
1019
1020
1021 /*
1022  * idl_intersection - return a = a intersection b
1023  */
1024 int
1025 bdb_idl_intersection(
1026         ID *a,
1027         ID *b )
1028 {
1029         ID ida, idb;
1030         ID idmax, idmin;
1031         ID cursora = 0, cursorb = 0, cursorc;
1032         int swap = 0;
1033
1034         if ( BDB_IDL_IS_ZERO( a ) || BDB_IDL_IS_ZERO( b ) ) {
1035                 a[0] = 0;
1036                 return 0;
1037         }
1038
1039         idmin = IDL_MAX( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1040         idmax = IDL_MIN( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1041         if ( idmin > idmax ) {
1042                 a[0] = 0;
1043                 return 0;
1044         } else if ( idmin == idmax ) {
1045                 a[0] = 1;
1046                 a[1] = idmin;
1047                 return 0;
1048         }
1049
1050         if ( BDB_IDL_IS_RANGE( a ) ) {
1051                 if ( BDB_IDL_IS_RANGE(b) ) {
1052                 /* If both are ranges, just shrink the boundaries */
1053                         a[1] = idmin;
1054                         a[2] = idmax;
1055                         return 0;
1056                 } else {
1057                 /* Else swap so that b is the range, a is a list */
1058                         ID *tmp = a;
1059                         a = b;
1060                         b = tmp;
1061                         swap = 1;
1062                 }
1063         }
1064
1065         /* If a range completely covers the list, the result is
1066          * just the list. If idmin to idmax is contiguous, just
1067          * turn it into a range.
1068          */
1069         if ( BDB_IDL_IS_RANGE( b )
1070                 && BDB_IDL_FIRST( b ) <= BDB_IDL_FIRST( a )
1071                 && BDB_IDL_LAST( b ) >= BDB_IDL_LAST( a ) ) {
1072                 if (idmax - idmin + 1 == a[0])
1073                 {
1074                         a[0] = NOID;
1075                         a[1] = idmin;
1076                         a[2] = idmax;
1077                 }
1078                 goto done;
1079         }
1080
1081         /* Fine, do the intersection one element at a time.
1082          * First advance to idmin in both IDLs.
1083          */
1084         cursora = cursorb = idmin;
1085         ida = bdb_idl_first( a, &cursora );
1086         idb = bdb_idl_first( b, &cursorb );
1087         cursorc = 0;
1088
1089         while( ida <= idmax || idb <= idmax ) {
1090                 if( ida == idb ) {
1091                         a[++cursorc] = ida;
1092                         ida = bdb_idl_next( a, &cursora );
1093                         idb = bdb_idl_next( b, &cursorb );
1094                 } else if ( ida < idb ) {
1095                         ida = bdb_idl_next( a, &cursora );
1096                 } else {
1097                         idb = bdb_idl_next( b, &cursorb );
1098                 }
1099         }
1100         a[0] = cursorc;
1101 done:
1102         if (swap)
1103                 BDB_IDL_CPY( b, a );
1104
1105         return 0;
1106 }
1107
1108
1109 /*
1110  * idl_union - return a = a union b
1111  */
1112 int
1113 bdb_idl_union(
1114         ID      *a,
1115         ID      *b )
1116 {
1117         ID ida, idb;
1118         ID cursora = 0, cursorb = 0, cursorc;
1119
1120         if ( BDB_IDL_IS_ZERO( b ) ) {
1121                 return 0;
1122         }
1123
1124         if ( BDB_IDL_IS_ZERO( a ) ) {
1125                 BDB_IDL_CPY( a, b );
1126                 return 0;
1127         }
1128
1129         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ) {
1130 over:           ida = IDL_MIN( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1131                 idb = IDL_MAX( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1132                 a[0] = NOID;
1133                 a[1] = ida;
1134                 a[2] = idb;
1135                 return 0;
1136         }
1137
1138         ida = bdb_idl_first( a, &cursora );
1139         idb = bdb_idl_first( b, &cursorb );
1140
1141         cursorc = b[0];
1142
1143         /* The distinct elements of a are cat'd to b */
1144         while( ida != NOID || idb != NOID ) {
1145                 if ( ida < idb ) {
1146                         if( ++cursorc > BDB_IDL_UM_MAX ) {
1147                                 goto over;
1148                         }
1149                         b[cursorc] = ida;
1150                         ida = bdb_idl_next( a, &cursora );
1151
1152                 } else {
1153                         if ( ida == idb )
1154                                 ida = bdb_idl_next( a, &cursora );
1155                         idb = bdb_idl_next( b, &cursorb );
1156                 }
1157         }
1158
1159         /* b is copied back to a in sorted order */
1160         a[0] = cursorc;
1161         cursora = 1;
1162         cursorb = 1;
1163         cursorc = b[0]+1;
1164         while (cursorb <= b[0] || cursorc <= a[0]) {
1165                 if (cursorc > a[0])
1166                         idb = NOID;
1167                 else
1168                         idb = b[cursorc];
1169                 if (cursorb <= b[0] && b[cursorb] < idb)
1170                         a[cursora++] = b[cursorb++];
1171                 else {
1172                         a[cursora++] = idb;
1173                         cursorc++;
1174                 }
1175         }
1176
1177         return 0;
1178 }
1179
1180
1181 #if 0
1182 /*
1183  * bdb_idl_notin - return a intersection ~b (or a minus b)
1184  */
1185 int
1186 bdb_idl_notin(
1187         ID      *a,
1188         ID      *b,
1189         ID *ids )
1190 {
1191         ID ida, idb;
1192         ID cursora = 0, cursorb = 0;
1193
1194         if( BDB_IDL_IS_ZERO( a ) ||
1195                 BDB_IDL_IS_ZERO( b ) ||
1196                 BDB_IDL_IS_RANGE( b ) )
1197         {
1198                 BDB_IDL_CPY( ids, a );
1199                 return 0;
1200         }
1201
1202         if( BDB_IDL_IS_RANGE( a ) ) {
1203                 BDB_IDL_CPY( ids, a );
1204                 return 0;
1205         }
1206
1207         ida = bdb_idl_first( a, &cursora ),
1208         idb = bdb_idl_first( b, &cursorb );
1209
1210         ids[0] = 0;
1211
1212         while( ida != NOID ) {
1213                 if ( idb == NOID ) {
1214                         /* we could shortcut this */
1215                         ids[++ids[0]] = ida;
1216                         ida = bdb_idl_next( a, &cursora );
1217
1218                 } else if ( ida < idb ) {
1219                         ids[++ids[0]] = ida;
1220                         ida = bdb_idl_next( a, &cursora );
1221
1222                 } else if ( ida > idb ) {
1223                         idb = bdb_idl_next( b, &cursorb );
1224
1225                 } else {
1226                         ida = bdb_idl_next( a, &cursora );
1227                         idb = bdb_idl_next( b, &cursorb );
1228                 }
1229         }
1230
1231         return 0;
1232 }
1233 #endif
1234
1235 ID bdb_idl_first( ID *ids, ID *cursor )
1236 {
1237         ID pos;
1238
1239         if ( ids[0] == 0 ) {
1240                 *cursor = NOID;
1241                 return NOID;
1242         }
1243
1244         if ( BDB_IDL_IS_RANGE( ids ) ) {
1245                 if( *cursor < ids[1] ) {
1246                         *cursor = ids[1];
1247                 }
1248                 return *cursor;
1249         }
1250
1251         if ( *cursor == 0 )
1252                 pos = 1;
1253         else
1254                 pos = bdb_idl_search( ids, *cursor );
1255
1256         if( pos > ids[0] ) {
1257                 return NOID;
1258         }
1259
1260         *cursor = pos;
1261         return ids[pos];
1262 }
1263
1264 ID bdb_idl_next( ID *ids, ID *cursor )
1265 {
1266         if ( BDB_IDL_IS_RANGE( ids ) ) {
1267                 if( ids[2] < ++(*cursor) ) {
1268                         return NOID;
1269                 }
1270                 return *cursor;
1271         }
1272
1273         if ( ++(*cursor) <= ids[0] ) {
1274                 return ids[*cursor];
1275         }
1276
1277         return NOID;
1278 }
1279
1280 #ifdef BDB_HIER
1281
1282 /* Add one ID to an unsorted list. We ensure that the first element is the
1283  * minimum and the last element is the maximum, for fast range compaction.
1284  *   this means IDLs up to length 3 are always sorted...
1285  */
1286 int bdb_idl_append_one( ID *ids, ID id )
1287 {
1288         if (BDB_IDL_IS_RANGE( ids )) {
1289                 /* if already in range, treat as a dup */
1290                 if (id >= BDB_IDL_FIRST(ids) && id <= BDB_IDL_LAST(ids))
1291                         return -1;
1292                 if (id < BDB_IDL_FIRST(ids))
1293                         ids[1] = id;
1294                 else if (id > BDB_IDL_LAST(ids))
1295                         ids[2] = id;
1296                 return 0;
1297         }
1298         if ( ids[0] ) {
1299                 ID tmp;
1300
1301                 if (id < ids[1]) {
1302                         tmp = ids[1];
1303                         ids[1] = id;
1304                         id = tmp;
1305                 }
1306                 if ( ids[0] > 1 && id < ids[ids[0]] ) {
1307                         tmp = ids[ids[0]];
1308                         ids[ids[0]] = id;
1309                         id = tmp;
1310                 }
1311         }
1312         ids[0]++;
1313         if ( ids[0] >= BDB_IDL_UM_MAX ) {
1314                 ids[0] = NOID;
1315                 ids[2] = id;
1316         } else {
1317                 ids[ids[0]] = id;
1318         }
1319         return 0;
1320 }
1321
1322 /* Append sorted list b to sorted list a. The result is unsorted but
1323  * a[1] is the min of the result and a[a[0]] is the max.
1324  */
1325 int bdb_idl_append( ID *a, ID *b )
1326 {
1327         ID ida, idb, tmp, swap = 0;
1328
1329         if ( BDB_IDL_IS_ZERO( b ) ) {
1330                 return 0;
1331         }
1332
1333         if ( BDB_IDL_IS_ZERO( a ) ) {
1334                 BDB_IDL_CPY( a, b );
1335                 return 0;
1336         }
1337
1338         ida = BDB_IDL_LAST( a );
1339         idb = BDB_IDL_LAST( b );
1340         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ||
1341                 a[0] + b[0] >= BDB_IDL_UM_MAX ) {
1342                 a[2] = IDL_MAX( ida, idb );
1343                 a[1] = IDL_MIN( a[1], b[1] );
1344                 a[0] = NOID;
1345                 return 0;
1346         }
1347
1348         if ( b[0] > 1 && ida > idb ) {
1349                 swap = idb;
1350                 a[a[0]] = idb;
1351                 b[b[0]] = ida;
1352         }
1353
1354         if ( b[1] < a[1] ) {
1355                 tmp = a[1];
1356                 a[1] = b[1];
1357         } else {
1358                 tmp = b[1];
1359         }
1360         a[0]++;
1361         a[a[0]] = tmp;
1362
1363         if ( b[0] > 1 ) {
1364                 int i = b[0] - 1;
1365                 AC_MEMCPY(a+a[0]+1, b+2, i * sizeof(ID));
1366                 a[0] += i;
1367         }
1368         if ( swap ) {
1369                 b[b[0]] = swap;
1370         }
1371         return 0;
1372 }
1373
1374 #if 1
1375
1376 /* Quicksort + Insertion sort for small arrays */
1377
1378 #define SMALL   8
1379 #define SWAP(a,b)       itmp=(a);(a)=(b);(b)=itmp
1380
1381 void
1382 bdb_idl_sort( ID *ids, ID *tmp )
1383 {
1384         int *istack = (int *)tmp;
1385         int i,j,k,l,ir,jstack;
1386         ID a, itmp;
1387
1388         if ( BDB_IDL_IS_RANGE( ids ))
1389                 return;
1390
1391         ir = ids[0];
1392         l = 1;
1393         jstack = 0;
1394         for(;;) {
1395                 if (ir - l < SMALL) {   /* Insertion sort */
1396                         for (j=l+1;j<=ir;j++) {
1397                                 a = ids[j];
1398                                 for (i=j-1;i>=1;i--) {
1399                                         if (ids[i] <= a) break;
1400                                         ids[i+1] = ids[i];
1401                                 }
1402                                 ids[i+1] = a;
1403                         }
1404                         if (jstack == 0) break;
1405                         ir = istack[jstack--];
1406                         l = istack[jstack--];
1407                 } else {
1408                         k = (l + ir) >> 1;      /* Choose median of left, center, right */
1409                         SWAP(ids[k], ids[l+1]);
1410                         if (ids[l] > ids[ir]) {
1411                                 SWAP(ids[l], ids[ir]);
1412                         }
1413                         if (ids[l+1] > ids[ir]) {
1414                                 SWAP(ids[l+1], ids[ir]);
1415                         }
1416                         if (ids[l] > ids[l+1]) {
1417                                 SWAP(ids[l], ids[l+1]);
1418                         }
1419                         i = l+1;
1420                         j = ir;
1421                         a = ids[l+1];
1422                         for(;;) {
1423                                 do i++; while(ids[i] < a);
1424                                 do j--; while(ids[j] > a);
1425                                 if (j < i) break;
1426                                 SWAP(ids[i],ids[j]);
1427                         }
1428                         ids[l+1] = ids[j];
1429                         ids[j] = a;
1430                         jstack += 2;
1431                         if (ir-i+1 >= j-1) {
1432                                 istack[jstack] = ir;
1433                                 istack[jstack-1] = i;
1434                                 ir = j-1;
1435                         } else {
1436                                 istack[jstack] = j-1;
1437                                 istack[jstack-1] = l;
1438                                 l = i;
1439                         }
1440                 }
1441         }
1442 }
1443
1444 #else
1445
1446 /* 8 bit Radix sort + insertion sort
1447  *
1448  * based on code from http://www.cubic.org/docs/radix.htm
1449  * with improvements by mbackes@symas.com and hyc@symas.com
1450  *
1451  * This code is O(n) but has a relatively high constant factor. For lists
1452  * up to ~50 Quicksort is slightly faster; up to ~100 they are even.
1453  * Much faster than quicksort for lists longer than ~100. Insertion
1454  * sort is actually superior for lists <50.
1455  */
1456
1457 #define BUCKETS (1<<8)
1458 #define SMALL   50
1459
1460 void
1461 bdb_idl_sort( ID *ids, ID *tmp )
1462 {
1463         int count, soft_limit, phase = 0, size = ids[0];
1464         ID *idls[2];
1465         unsigned char *maxv = (unsigned char *)&ids[size];
1466
1467         if ( BDB_IDL_IS_RANGE( ids ))
1468                 return;
1469
1470         /* Use insertion sort for small lists */
1471         if ( size <= SMALL ) {
1472                 int i,j;
1473                 ID a;
1474
1475                 for (j=1;j<=size;j++) {
1476                         a = ids[j];
1477                         for (i=j-1;i>=1;i--) {
1478                                 if (ids[i] <= a) break;
1479                                 ids[i+1] = ids[i];
1480                         }
1481                         ids[i+1] = a;
1482                 }
1483                 return;
1484         }
1485
1486         tmp[0] = size;
1487         idls[0] = ids;
1488         idls[1] = tmp;
1489
1490 #if BYTE_ORDER == BIG_ENDIAN
1491     for (soft_limit = 0; !maxv[soft_limit]; soft_limit++);
1492 #else
1493     for (soft_limit = sizeof(ID)-1; !maxv[soft_limit]; soft_limit--);
1494 #endif
1495
1496         for (
1497 #if BYTE_ORDER == BIG_ENDIAN
1498         count = sizeof(ID)-1; count >= soft_limit; --count
1499 #else
1500         count = 0; count <= soft_limit; ++count
1501 #endif
1502         ) {
1503                 unsigned int num[BUCKETS], * np, n, sum;
1504                 int i;
1505         ID *sp, *source, *dest;
1506         unsigned char *bp, *source_start;
1507
1508                 source = idls[phase]+1;
1509                 dest = idls[phase^1]+1;
1510                 source_start =  ((unsigned char *) source) + count;
1511
1512         np = num;
1513         for ( i = BUCKETS; i > 0; --i ) *np++ = 0;
1514
1515                 /* count occurences of every byte value */
1516                 bp = source_start;
1517         for ( i = size; i > 0; --i, bp += sizeof(ID) )
1518                                 num[*bp]++;
1519
1520                 /* transform count into index by summing elements and storing
1521                  * into same array
1522                  */
1523         sum = 0;
1524         np = num;
1525         for ( i = BUCKETS; i > 0; --i ) {
1526                 n = *np;
1527                 *np++ = sum;
1528                 sum += n;
1529         }
1530
1531                 /* fill dest with the right values in the right place */
1532                 bp = source_start;
1533         sp = source;
1534         for ( i = size; i > 0; --i, bp += sizeof(ID) ) {
1535                 np = num + *bp;
1536                 dest[*np] = *sp++;
1537                 ++(*np);
1538         }
1539                 phase ^= 1;
1540         }
1541
1542         /* copy back from temp if needed */
1543         if ( phase ) {
1544                 ids++; tmp++;
1545                 for ( count = 0; count < size; ++count )
1546                         *ids++ = *tmp++;
1547         }
1548 }
1549 #endif  /* Quick vs Radix */
1550
1551 #endif  /* BDB_HIER */