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 2000-2011 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 ) { \
  32                 if ( (e)->idl_lru_next == (bdb)->bi_idl_lru_head ) { \
  33                         (bdb)->bi_idl_lru_head = NULL; \
  34                 } else { \
  35                         (bdb)->bi_idl_lru_head = (e)->idl_lru_next; \
  36                 } \
  37         } \
  38         if ( (e) == (bdb)->bi_idl_lru_tail ) { \
  39                 if ( (e)->idl_lru_prev == (bdb)->bi_idl_lru_tail ) { \
  40                         assert( (bdb)->bi_idl_lru_head == NULL ); \
  41                         (bdb)->bi_idl_lru_tail = NULL; \
  42                 } else { \
  43                         (bdb)->bi_idl_lru_tail = (e)->idl_lru_prev; \
  44                 } \
  45         } \
  46         (e)->idl_lru_next->idl_lru_prev = (e)->idl_lru_prev; \
  47         (e)->idl_lru_prev->idl_lru_next = (e)->idl_lru_next; \
  48 } while ( 0 )
  49
  50 static int
  51 bdb_idl_entry_cmp( const void *v_idl1, const void *v_idl2 )
  52 {
  53         const bdb_idl_cache_entry_t *idl1 = v_idl1, *idl2 = v_idl2;
  54         int rc;
  55
  56         if ((rc = SLAP_PTRCMP( idl1->db, idl2->db ))) return rc;
  57         if ((rc = idl1->kstr.bv_len - idl2->kstr.bv_len )) return rc;
  58         return ( memcmp ( idl1->kstr.bv_val, idl2->kstr.bv_val , idl1->kstr.bv_len ) );
  59 }
  60
  61 #if IDL_DEBUG > 0
  62 static void idl_check( ID *ids )
  63 {
  64         if( BDB_IDL_IS_RANGE( ids ) ) {
  65                 assert( BDB_IDL_RANGE_FIRST(ids) <= BDB_IDL_RANGE_LAST(ids) );
  66         } else {
  67                 ID i;
  68                 for( i=1; i < ids[0]; i++ ) {
  69                         assert( ids[i+1] > ids[i] );
  70                 }
  71         }
  72 }
  73
  74 #if IDL_DEBUG > 1
  75 static void idl_dump( ID *ids )
  76 {
  77         if( BDB_IDL_IS_RANGE( ids ) ) {
  78                 Debug( LDAP_DEBUG_ANY,
  79                         "IDL: range ( %ld - %ld )\n",
  80                         (long) BDB_IDL_RANGE_FIRST( ids ),
  81                         (long) BDB_IDL_RANGE_LAST( ids ) );
  82
  83         } else {
  84                 ID i;
  85                 Debug( LDAP_DEBUG_ANY, "IDL: size %ld", (long) ids[0], 0, 0 );
  86
  87                 for( i=1; i<=ids[0]; i++ ) {
  88                         if( i % 16 == 1 ) {
  89                                 Debug( LDAP_DEBUG_ANY, "\n", 0, 0, 0 );
  90                         }
  91                         Debug( LDAP_DEBUG_ANY, "  %02lx", (long) ids[i], 0, 0 );
  92                 }
  93
  94                 Debug( LDAP_DEBUG_ANY, "\n", 0, 0, 0 );
  95         }
  96
  97         idl_check( ids );
  98 }
  99 #endif /* IDL_DEBUG > 1 */
 100 #endif /* IDL_DEBUG > 0 */
 101
 102 unsigned bdb_idl_search( ID *ids, ID id )
 103 {
 104 #define IDL_BINARY_SEARCH 1
 105 #ifdef IDL_BINARY_SEARCH
 106         /*
 107          * binary search of id in ids
 108          * if found, returns position of id
 109          * if not found, returns first postion greater than id
 110          */
 111         unsigned base = 0;
 112         unsigned cursor = 0;
 113         int val = 0;
 114         unsigned n = ids[0];
 115
 116 #if IDL_DEBUG > 0
 117         idl_check( ids );
 118 #endif
 119
 120         while( 0 < n ) {
 121                 int pivot = n >> 1;
 122                 cursor = base + pivot;
 123                 val = IDL_CMP( id, ids[cursor + 1] );
 124
 125                 if( val < 0 ) {
 126                         n = pivot;
 127
 128                 } else if ( val > 0 ) {
 129                         base = cursor + 1;
 130                         n -= pivot + 1;
 131
 132                 } else {
 133                         return cursor + 1;
 134                 }
 135         }
 136
 137         if( val > 0 ) {
 138                 return cursor + 2;
 139         } else {
 140                 return cursor + 1;
 141         }
 142
 143 #else
 144         /* (reverse) linear search */
 145         int i;
 146
 147 #if IDL_DEBUG > 0
 148         idl_check( ids );
 149 #endif
 150
 151         for( i=ids[0]; i; i-- ) {
 152                 if( id > ids[i] ) {
 153                         break;
 154                 }
 155         }
 156
 157         return i+1;
 158 #endif
 159 }
 160
 161 int bdb_idl_insert( ID *ids, ID id )
 162 {
 163         unsigned x;
 164
 165 #if IDL_DEBUG > 1
 166         Debug( LDAP_DEBUG_ANY, "insert: %04lx at %d\n", (long) id, x, 0 );
 167         idl_dump( ids );
 168 #elif IDL_DEBUG > 0
 169         idl_check( ids );
 170 #endif
 171
 172         if (BDB_IDL_IS_RANGE( ids )) {
 173                 /* if already in range, treat as a dup */
 174                 if (id >= BDB_IDL_FIRST(ids) && id <= BDB_IDL_LAST(ids))
 175                         return -1;
 176                 if (id < BDB_IDL_FIRST(ids))
 177                         ids[1] = id;
 178                 else if (id > BDB_IDL_LAST(ids))
 179                         ids[2] = id;
 180                 return 0;
 181         }
 182
 183         x = bdb_idl_search( ids, id );
 184         assert( x > 0 );
 185
 186         if( x < 1 ) {
 187                 /* internal error */
 188                 return -2;
 189         }
 190
 191         if ( x <= ids[0] && ids[x] == id ) {
 192                 /* duplicate */
 193                 return -1;
 194         }
 195
 196         if ( ++ids[0] >= BDB_IDL_DB_MAX ) {
 197                 if( id < ids[1] ) {
 198                         ids[1] = id;
 199                         ids[2] = ids[ids[0]-1];
 200                 } else if ( ids[ids[0]-1] < id ) {
 201                         ids[2] = id;
 202                 } else {
 203                         ids[2] = ids[ids[0]-1];
 204                 }
 205                 ids[0] = NOID;
 206
 207         } else {
 208                 /* insert id */
 209                 AC_MEMCPY( &ids[x+1], &ids[x], (ids[0]-x) * sizeof(ID) );
 210                 ids[x] = id;
 211         }
 212
 213 #if IDL_DEBUG > 1
 214         idl_dump( ids );
 215 #elif IDL_DEBUG > 0
 216         idl_check( ids );
 217 #endif
 218
 219         return 0;
 220 }
 221
 222 int bdb_idl_delete( ID *ids, ID id )
 223 {
 224         unsigned x;
 225
 226 #if IDL_DEBUG > 1
 227         Debug( LDAP_DEBUG_ANY, "delete: %04lx at %d\n", (long) id, x, 0 );
 228         idl_dump( ids );
 229 #elif IDL_DEBUG > 0
 230         idl_check( ids );
 231 #endif
 232
 233         if (BDB_IDL_IS_RANGE( ids )) {
 234                 /* If deleting a range boundary, adjust */
 235                 if ( ids[1] == id )
 236                         ids[1]++;
 237                 else if ( ids[2] == id )
 238                         ids[2]--;
 239                 /* deleting from inside a range is a no-op */
 240
 241                 /* If the range has collapsed, re-adjust */
 242                 if ( ids[1] > ids[2] )
 243                         ids[0] = 0;
 244                 else if ( ids[1] == ids[2] )
 245                         ids[1] = 1;
 246                 return 0;
 247         }
 248
 249         x = bdb_idl_search( ids, id );
 250         assert( x > 0 );
 251
 252         if( x <= 0 ) {
 253                 /* internal error */
 254                 return -2;
 255         }
 256
 257         if( x > ids[0] || ids[x] != id ) {
 258                 /* not found */
 259                 return -1;
 260
 261         } else if ( --ids[0] == 0 ) {
 262                 if( x != 1 ) {
 263                         return -3;
 264                 }
 265
 266         } else {
 267                 AC_MEMCPY( &ids[x], &ids[x+1], (1+ids[0]-x) * sizeof(ID) );
 268         }
 269
 270 #if IDL_DEBUG > 1
 271         idl_dump( ids );
 272 #elif IDL_DEBUG > 0
 273         idl_check( ids );
 274 #endif
 275
 276         return 0;
 277 }
 278
 279 static char *
 280 bdb_show_key(
 281         DBT             *key,
 282         char            *buf )
 283 {
 284         if ( key->size == 4 /* LUTIL_HASH_BYTES */ ) {
 285                 unsigned char *c = key->data;
 286                 sprintf( buf, "[%02x%02x%02x%02x]", c[0], c[1], c[2], c[3] );
 287                 return buf;
 288         } else {
 289                 return key->data;
 290         }
 291 }
 292
 293 /* Find a db/key pair in the IDL cache. If ids is non-NULL,
 294  * copy the cached IDL into it, otherwise just return the status.
 295  */
 296 int
 297 bdb_idl_cache_get(
 298         struct bdb_info *bdb,
 299         DB                      *db,
 300         DBT                     *key,
 301         ID                      *ids )
 302 {
 303         bdb_idl_cache_entry_t idl_tmp;
 304         bdb_idl_cache_entry_t *matched_idl_entry;
 305         int rc = LDAP_NO_SUCH_OBJECT;
 306
 307         DBT2bv( key, &idl_tmp.kstr );
 308         idl_tmp.db = db;
 309         ldap_pvt_thread_rdwr_rlock( &bdb->bi_idl_tree_rwlock );
 310         matched_idl_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 311                                       bdb_idl_entry_cmp );
 312         if ( matched_idl_entry != NULL ) {
 313                 if ( matched_idl_entry->idl && ids )
 314                         BDB_IDL_CPY( ids, matched_idl_entry->idl );
 315                 matched_idl_entry->idl_flags |= CACHE_ENTRY_REFERENCED;
 316                 if ( matched_idl_entry->idl )
 317                         rc = LDAP_SUCCESS;
 318                 else
 319                         rc = DB_NOTFOUND;
 320         }
 321         ldap_pvt_thread_rdwr_runlock( &bdb->bi_idl_tree_rwlock );
 322
 323         return rc;
 324 }
 325
 326 void
 327 bdb_idl_cache_put(
 328         struct bdb_info *bdb,
 329         DB                      *db,
 330         DBT                     *key,
 331         ID                      *ids,
 332         int                     rc )
 333 {
 334         bdb_idl_cache_entry_t idl_tmp;
 335         bdb_idl_cache_entry_t *ee, *eprev;
 336
 337         if ( rc == DB_NOTFOUND || BDB_IDL_IS_ZERO( ids ))
 338                 return;
 339
 340         DBT2bv( key, &idl_tmp.kstr );
 341
 342         ee = (bdb_idl_cache_entry_t *) ch_malloc(
 343                 sizeof( bdb_idl_cache_entry_t ) );
 344         ee->db = db;
 345         ee->idl = (ID*) ch_malloc( BDB_IDL_SIZEOF ( ids ) );
 346         BDB_IDL_CPY( ee->idl, ids );
 347
 348         ee->idl_lru_prev = NULL;
 349         ee->idl_lru_next = NULL;
 350         ee->idl_flags = 0;
 351         ber_dupbv( &ee->kstr, &idl_tmp.kstr );
 352         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 353         if ( avl_insert( &bdb->bi_idl_tree, (caddr_t) ee,
 354                 bdb_idl_entry_cmp, avl_dup_error ))
 355         {
 356                 ch_free( ee->kstr.bv_val );
 357                 ch_free( ee->idl );
 358                 ch_free( ee );
 359                 ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 360                 return;
 361         }
 362         ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 363         /* LRU_ADD */
 364         if ( bdb->bi_idl_lru_head ) {
 365                 assert( bdb->bi_idl_lru_tail != NULL );
 366                 assert( bdb->bi_idl_lru_head->idl_lru_prev != NULL );
 367                 assert( bdb->bi_idl_lru_head->idl_lru_next != NULL );
 368
 369                 ee->idl_lru_next = bdb->bi_idl_lru_head;
 370                 ee->idl_lru_prev = bdb->bi_idl_lru_head->idl_lru_prev;
 371                 bdb->bi_idl_lru_head->idl_lru_prev->idl_lru_next = ee;
 372                 bdb->bi_idl_lru_head->idl_lru_prev = ee;
 373         } else {
 374                 ee->idl_lru_next = ee->idl_lru_prev = ee;
 375                 bdb->bi_idl_lru_tail = ee;
 376         }
 377         bdb->bi_idl_lru_head = ee;
 378
 379         if ( bdb->bi_idl_cache_size >= bdb->bi_idl_cache_max_size ) {
 380                 int i;
 381                 eprev = bdb->bi_idl_lru_tail;
 382                 for ( i = 0; (ee = eprev) != NULL && i < 10; i++ ) {
 383                         eprev = ee->idl_lru_prev;
 384                         if ( eprev == ee ) {
 385                                 eprev = NULL;
 386                         }
 387                         if ( ee->idl_flags & CACHE_ENTRY_REFERENCED ) {
 388                                 ee->idl_flags ^= CACHE_ENTRY_REFERENCED;
 389                                 continue;
 390                         }
 391                         if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) ee,
 392                                     bdb_idl_entry_cmp ) == NULL ) {
 393                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_put: "
 394                                         "AVL delete failed\n",
 395                                         0, 0, 0 );
 396                         }
 397                         IDL_LRU_DELETE( bdb, ee );
 398                         i++;
 399                         --bdb->bi_idl_cache_size;
 400                         ch_free( ee->kstr.bv_val );
 401                         ch_free( ee->idl );
 402                         ch_free( ee );
 403                 }
 404                 bdb->bi_idl_lru_tail = eprev;
 405                 assert( bdb->bi_idl_lru_tail != NULL
 406                         || bdb->bi_idl_lru_head == NULL );
 407         }
 408         bdb->bi_idl_cache_size++;
 409         ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 410         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 411 }
 412
 413 void
 414 bdb_idl_cache_del(
 415         struct bdb_info *bdb,
 416         DB                      *db,
 417         DBT                     *key )
 418 {
 419         bdb_idl_cache_entry_t *matched_idl_entry, idl_tmp;
 420         DBT2bv( key, &idl_tmp.kstr );
 421         idl_tmp.db = db;
 422         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 423         matched_idl_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 424                                       bdb_idl_entry_cmp );
 425         if ( matched_idl_entry != NULL ) {
 426                 if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) matched_idl_entry,
 427                                     bdb_idl_entry_cmp ) == NULL ) {
 428                         Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_del: "
 429                                 "AVL delete failed\n",
 430                                 0, 0, 0 );
 431                 }
 432                 --bdb->bi_idl_cache_size;
 433                 ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 434                 IDL_LRU_DELETE( bdb, matched_idl_entry );
 435                 ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 436                 free( matched_idl_entry->kstr.bv_val );
 437                 if ( matched_idl_entry->idl )
 438                         free( matched_idl_entry->idl );
 439                 free( matched_idl_entry );
 440         }
 441         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 442 }
 443
 444 void
 445 bdb_idl_cache_add_id(
 446         struct bdb_info *bdb,
 447         DB                      *db,
 448         DBT                     *key,
 449         ID                      id )
 450 {
 451         bdb_idl_cache_entry_t *cache_entry, idl_tmp;
 452         DBT2bv( key, &idl_tmp.kstr );
 453         idl_tmp.db = db;
 454         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 455         cache_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 456                                       bdb_idl_entry_cmp );
 457         if ( cache_entry != NULL ) {
 458                 if ( !BDB_IDL_IS_RANGE( cache_entry->idl ) &&
 459                         cache_entry->idl[0] < BDB_IDL_DB_MAX ) {
 460                         size_t s = BDB_IDL_SIZEOF( cache_entry->idl ) + sizeof(ID);
 461                         cache_entry->idl = ch_realloc( cache_entry->idl, s );
 462                 }
 463                 bdb_idl_insert( cache_entry->idl, id );
 464         }
 465         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 466 }
 467
 468 void
 469 bdb_idl_cache_del_id(
 470         struct bdb_info *bdb,
 471         DB                      *db,
 472         DBT                     *key,
 473         ID                      id )
 474 {
 475         bdb_idl_cache_entry_t *cache_entry, idl_tmp;
 476         DBT2bv( key, &idl_tmp.kstr );
 477         idl_tmp.db = db;
 478         ldap_pvt_thread_rdwr_wlock( &bdb->bi_idl_tree_rwlock );
 479         cache_entry = avl_find( bdb->bi_idl_tree, &idl_tmp,
 480                                       bdb_idl_entry_cmp );
 481         if ( cache_entry != NULL ) {
 482                 bdb_idl_delete( cache_entry->idl, id );
 483                 if ( cache_entry->idl[0] == 0 ) {
 484                         if ( avl_delete( &bdb->bi_idl_tree, (caddr_t) cache_entry,
 485                                                 bdb_idl_entry_cmp ) == NULL ) {
 486                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_cache_del: "
 487                                         "AVL delete failed\n",
 488                                         0, 0, 0 );
 489                         }
 490                         --bdb->bi_idl_cache_size;
 491                         ldap_pvt_thread_mutex_lock( &bdb->bi_idl_tree_lrulock );
 492                         IDL_LRU_DELETE( bdb, cache_entry );
 493                         ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
 494                         free( cache_entry->kstr.bv_val );
 495                         free( cache_entry->idl );
 496                         free( cache_entry );
 497                 }
 498         }
 499         ldap_pvt_thread_rdwr_wunlock( &bdb->bi_idl_tree_rwlock );
 500 }
 501
 502 int
 503 bdb_idl_fetch_key(
 504         BackendDB       *be,
 505         DB                      *db,
 506         DB_TXN          *txn,
 507         DBT                     *key,
 508         ID                      *ids,
 509         DBC                     **saved_cursor,
 510         int                     get_flag )
 511 {
 512         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 513         int rc;
 514         DBT data, key2, *kptr;
 515         DBC *cursor;
 516         ID *i;
 517         void *ptr;
 518         size_t len;
 519         int rc2;
 520         int flags = bdb->bi_db_opflags | DB_MULTIPLE;
 521         int opflag;
 522
 523         /* If using BerkeleyDB 4.0, the buf must be large enough to
 524          * grab the entire IDL in one get(), otherwise BDB will leak
 525          * resources on subsequent get's.  We can safely call get()
 526          * twice - once for the data, and once to get the DB_NOTFOUND
 527          * result meaning there's no more data. See ITS#2040 for details.
 528          * This bug is fixed in BDB 4.1 so a smaller buffer will work if
 529          * stack space is too limited.
 530          *
 531          * configure now requires Berkeley DB 4.1.
 532          */
 533 #if DB_VERSION_FULL < 0x04010000
 534 #       define BDB_ENOUGH 5
 535 #else
 536         /* We sometimes test with tiny IDLs, and BDB always wants buffers
 537          * that are at least one page in size.
 538          */
 539 # if BDB_IDL_DB_SIZE < 4096
 540 #   define BDB_ENOUGH 2048
 541 # else
 542 #       define BDB_ENOUGH 1
 543 # endif
 544 #endif
 545         ID buf[BDB_IDL_DB_SIZE*BDB_ENOUGH];
 546
 547         char keybuf[16];
 548
 549         Debug( LDAP_DEBUG_ARGS,
 550                 "bdb_idl_fetch_key: %s\n",
 551                 bdb_show_key( key, keybuf ), 0, 0 );
 552
 553         assert( ids != NULL );
 554
 555         if ( saved_cursor && *saved_cursor ) {
 556                 opflag = DB_NEXT;
 557         } else if ( get_flag == LDAP_FILTER_GE ) {
 558                 opflag = DB_SET_RANGE;
 559         } else if ( get_flag == LDAP_FILTER_LE ) {
 560                 opflag = DB_FIRST;
 561         } else {
 562                 opflag = DB_SET;
 563         }
 564
 565         /* only non-range lookups can use the IDL cache */
 566         if ( bdb->bi_idl_cache_size && opflag == DB_SET ) {
 567                 rc = bdb_idl_cache_get( bdb, db, key, ids );
 568                 if ( rc != LDAP_NO_SUCH_OBJECT ) return rc;
 569         }
 570
 571         DBTzero( &data );
 572
 573         data.data = buf;
 574         data.ulen = sizeof(buf);
 575         data.flags = DB_DBT_USERMEM;
 576
 577         /* If we're not reusing an existing cursor, get a new one */
 578         if( opflag != DB_NEXT ) {
 579                 rc = db->cursor( db, txn, &cursor, bdb->bi_db_opflags );
 580                 if( rc != 0 ) {
 581                         Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 582                                 "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 583                         return rc;
 584                 }
 585         } else {
 586                 cursor = *saved_cursor;
 587         }
 588
 589         /* If this is a LE lookup, save original key so we can determine
 590          * when to stop. If this is a GE lookup, save the key since it
 591          * will be overwritten.
 592          */
 593         if ( get_flag == LDAP_FILTER_LE || get_flag == LDAP_FILTER_GE ) {
 594                 DBTzero( &key2 );
 595                 key2.flags = DB_DBT_USERMEM;
 596                 key2.ulen = sizeof(keybuf);
 597                 key2.data = keybuf;
 598                 key2.size = key->size;
 599                 AC_MEMCPY( keybuf, key->data, key->size );
 600                 kptr = &key2;
 601         } else {
 602                 kptr = key;
 603         }
 604         len = key->size;
 605         rc = cursor->c_get( cursor, kptr, &data, flags | opflag );
 606
 607         /* skip presence key on range inequality lookups */
 608         while (rc == 0 && kptr->size != len) {
 609                 rc = cursor->c_get( cursor, kptr, &data, flags | DB_NEXT_NODUP );
 610         }
 611         /* If we're doing a LE compare and the new key is greater than
 612          * our search key, we're done
 613          */
 614         if (rc == 0 && get_flag == LDAP_FILTER_LE && memcmp( kptr->data,
 615                 key->data, key->size ) > 0 ) {
 616                 rc = DB_NOTFOUND;
 617         }
 618         if (rc == 0) {
 619                 i = ids;
 620                 while (rc == 0) {
 621                         u_int8_t *j;
 622
 623                         DB_MULTIPLE_INIT( ptr, &data );
 624                         while (ptr) {
 625                                 DB_MULTIPLE_NEXT(ptr, &data, j, len);
 626                                 if (j) {
 627                                         ++i;
 628                                         BDB_DISK2ID( j, i );
 629                                 }
 630                         }
 631                         rc = cursor->c_get( cursor, key, &data, flags | DB_NEXT_DUP );
 632                 }
 633                 if ( rc == DB_NOTFOUND ) rc = 0;
 634                 ids[0] = i - ids;
 635                 /* On disk, a range is denoted by 0 in the first element */
 636                 if (ids[1] == 0) {
 637                         if (ids[0] != BDB_IDL_RANGE_SIZE) {
 638                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 639                                         "range size mismatch: expected %d, got %ld\n",
 640                                         BDB_IDL_RANGE_SIZE, ids[0], 0 );
 641                                 cursor->c_close( cursor );
 642                                 return -1;
 643                         }
 644                         BDB_IDL_RANGE( ids, ids[2], ids[3] );
 645                 }
 646                 data.size = BDB_IDL_SIZEOF(ids);
 647         }
 648
 649         if ( saved_cursor && rc == 0 ) {
 650                 if ( !*saved_cursor )
 651                         *saved_cursor = cursor;
 652                 rc2 = 0;
 653         }
 654         else
 655                 rc2 = cursor->c_close( cursor );
 656         if (rc2) {
 657                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 658                         "close failed: %s (%d)\n", db_strerror(rc2), rc2, 0 );
 659                 return rc2;
 660         }
 661
 662         if( rc == DB_NOTFOUND ) {
 663                 return rc;
 664
 665         } else if( rc != 0 ) {
 666                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 667                         "get failed: %s (%d)\n",
 668                         db_strerror(rc), rc, 0 );
 669                 return rc;
 670
 671         } else if ( data.size == 0 || data.size % sizeof( ID ) ) {
 672                 /* size not multiple of ID size */
 673                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 674                         "odd size: expected %ld multiple, got %ld\n",
 675                         (long) sizeof( ID ), (long) data.size, 0 );
 676                 return -1;
 677
 678         } else if ( data.size != BDB_IDL_SIZEOF(ids) ) {
 679                 /* size mismatch */
 680                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 681                         "get size mismatch: expected %ld, got %ld\n",
 682                         (long) ((1 + ids[0]) * sizeof( ID )), (long) data.size, 0 );
 683                 return -1;
 684         }
 685
 686         if ( bdb->bi_idl_cache_max_size ) {
 687                 bdb_idl_cache_put( bdb, db, key, ids, rc );
 688         }
 689
 690         return rc;
 691 }
 692
 693
 694 int
 695 bdb_idl_insert_key(
 696         BackendDB       *be,
 697         DB                      *db,
 698         DB_TXN          *tid,
 699         DBT                     *key,
 700         ID                      id )
 701 {
 702         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 703         int     rc;
 704         DBT data;
 705         DBC *cursor;
 706         ID lo, hi, nlo, nhi, nid;
 707         char *err;
 708
 709         {
 710                 char buf[16];
 711                 Debug( LDAP_DEBUG_ARGS,
 712                         "bdb_idl_insert_key: %lx %s\n",
 713                         (long) id, bdb_show_key( key, buf ), 0 );
 714         }
 715
 716         assert( id != NOID );
 717
 718         DBTzero( &data );
 719         data.size = sizeof( ID );
 720         data.ulen = data.size;
 721         data.flags = DB_DBT_USERMEM;
 722
 723         BDB_ID2DISK( id, &nid );
 724
 725         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 726         if ( rc != 0 ) {
 727                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 728                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 729                 return rc;
 730         }
 731         data.data = &nlo;
 732         /* Fetch the first data item for this key, to see if it
 733          * exists and if it's a range.
 734          */
 735         rc = cursor->c_get( cursor, key, &data, DB_SET );
 736         err = "c_get";
 737         if ( rc == 0 ) {
 738                 if ( nlo != 0 ) {
 739                         /* not a range, count the number of items */
 740                         db_recno_t count;
 741                         rc = cursor->c_count( cursor, &count, 0 );
 742                         if ( rc != 0 ) {
 743                                 err = "c_count";
 744                                 goto fail;
 745                         }
 746                         if ( count >= BDB_IDL_DB_MAX ) {
 747                         /* No room, convert to a range */
 748                                 DBT key2 = *key;
 749                                 db_recno_t i;
 750
 751                                 key2.dlen = key2.ulen;
 752                                 key2.flags |= DB_DBT_PARTIAL;
 753
 754                                 BDB_DISK2ID( &nlo, &lo );
 755                                 data.data = &nhi;
 756
 757                                 rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_NODUP );
 758                                 if ( rc != 0 && rc != DB_NOTFOUND ) {
 759                                         err = "c_get next_nodup";
 760                                         goto fail;
 761                                 }
 762                                 if ( rc == DB_NOTFOUND ) {
 763                                         rc = cursor->c_get( cursor, key, &data, DB_LAST );
 764                                         if ( rc != 0 ) {
 765                                                 err = "c_get last";
 766                                                 goto fail;
 767                                         }
 768                                 } else {
 769                                         rc = cursor->c_get( cursor, key, &data, DB_PREV );
 770                                         if ( rc != 0 ) {
 771                                                 err = "c_get prev";
 772                                                 goto fail;
 773                                         }
 774                                 }
 775                                 BDB_DISK2ID( &nhi, &hi );
 776                                 /* Update hi/lo if needed, then delete all the items
 777                                  * between lo and hi
 778                                  */
 779                                 if ( id < lo ) {
 780                                         lo = id;
 781                                         nlo = nid;
 782                                 } else if ( id > hi ) {
 783                                         hi = id;
 784                                         nhi = nid;
 785                                 }
 786                                 data.data = &nid;
 787                                 /* Don't fetch anything, just position cursor */
 788                                 data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 789                                 data.dlen = data.ulen = 0;
 790                                 rc = cursor->c_get( cursor, key, &data, DB_SET );
 791                                 if ( rc != 0 ) {
 792                                         err = "c_get 2";
 793                                         goto fail;
 794                                 }
 795                                 rc = cursor->c_del( cursor, 0 );
 796                                 if ( rc != 0 ) {
 797                                         err = "c_del range1";
 798                                         goto fail;
 799                                 }
 800                                 /* Delete all the records */
 801                                 for ( i=1; i<count; i++ ) {
 802                                         rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_DUP );
 803                                         if ( rc != 0 ) {
 804                                                 err = "c_get next_dup";
 805                                                 goto fail;
 806                                         }
 807                                         rc = cursor->c_del( cursor, 0 );
 808                                         if ( rc != 0 ) {
 809                                                 err = "c_del range";
 810                                                 goto fail;
 811                                         }
 812                                 }
 813                                 /* Store the range marker */
 814                                 data.size = data.ulen = sizeof(ID);
 815                                 data.flags = DB_DBT_USERMEM;
 816                                 nid = 0;
 817                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 818                                 if ( rc != 0 ) {
 819                                         err = "c_put range";
 820                                         goto fail;
 821                                 }
 822                                 nid = nlo;
 823                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 824                                 if ( rc != 0 ) {
 825                                         err = "c_put lo";
 826                                         goto fail;
 827                                 }
 828                                 nid = nhi;
 829                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 830                                 if ( rc != 0 ) {
 831                                         err = "c_put hi";
 832                                         goto fail;
 833                                 }
 834                         } else {
 835                         /* There's room, just store it */
 836                                 goto put1;
 837                         }
 838                 } else {
 839                         /* It's a range, see if we need to rewrite
 840                          * the boundaries
 841                          */
 842                         hi = id;
 843                         data.data = &nlo;
 844                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 845                         if ( rc != 0 ) {
 846                                 err = "c_get lo";
 847                                 goto fail;
 848                         }
 849                         BDB_DISK2ID( &nlo, &lo );
 850                         if ( id > lo ) {
 851                                 data.data = &nhi;
 852                                 rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 853                                 if ( rc != 0 ) {
 854                                         err = "c_get hi";
 855                                         goto fail;
 856                                 }
 857                                 BDB_DISK2ID( &nhi, &hi );
 858                         }
 859                         if ( id < lo || id > hi ) {
 860                                 /* Delete the current lo/hi */
 861                                 rc = cursor->c_del( cursor, 0 );
 862                                 if ( rc != 0 ) {
 863                                         err = "c_del";
 864                                         goto fail;
 865                                 }
 866                                 data.data = &nid;
 867                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 868                                 if ( rc != 0 ) {
 869                                         err = "c_put lo/hi";
 870                                         goto fail;
 871                                 }
 872                         }
 873                 }
 874         } else if ( rc == DB_NOTFOUND ) {
 875 put1:           data.data = &nid;
 876                 rc = cursor->c_put( cursor, key, &data, DB_NODUPDATA );
 877                 /* Don't worry if it's already there */
 878                 if ( rc != 0 && rc != DB_KEYEXIST ) {
 879                         err = "c_put id";
 880                         goto fail;
 881                 }
 882         } else {
 883                 /* initial c_get failed, nothing was done */
 884 fail:
 885                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 886                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
 887                 cursor->c_close( cursor );
 888                 return rc;
 889         }
 890         /* If key was added (didn't already exist) and using IDL cache,
 891          * update key in IDL cache.
 892          */
 893         if ( !rc && bdb->bi_idl_cache_max_size ) {
 894                 bdb_idl_cache_add_id( bdb, db, key, id );
 895         }
 896         rc = cursor->c_close( cursor );
 897         if( rc != 0 ) {
 898                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 899                         "c_close failed: %s (%d)\n",
 900                         db_strerror(rc), rc, 0 );
 901         }
 902         return rc;
 903 }
 904
 905 int
 906 bdb_idl_delete_key(
 907         BackendDB       *be,
 908         DB                      *db,
 909         DB_TXN          *tid,
 910         DBT                     *key,
 911         ID                      id )
 912 {
 913         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 914         int     rc;
 915         DBT data;
 916         DBC *cursor;
 917         ID lo, hi, tmp, nid, nlo, nhi;
 918         char *err;
 919
 920         {
 921                 char buf[16];
 922                 Debug( LDAP_DEBUG_ARGS,
 923                         "bdb_idl_delete_key: %lx %s\n",
 924                         (long) id, bdb_show_key( key, buf ), 0 );
 925         }
 926         assert( id != NOID );
 927
 928         if ( bdb->bi_idl_cache_size ) {
 929                 bdb_idl_cache_del( bdb, db, key );
 930         }
 931
 932         BDB_ID2DISK( id, &nid );
 933
 934         DBTzero( &data );
 935         data.data = &tmp;
 936         data.size = sizeof( id );
 937         data.ulen = data.size;
 938         data.flags = DB_DBT_USERMEM;
 939
 940         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 941         if ( rc != 0 ) {
 942                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
 943                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 944                 return rc;
 945         }
 946         /* Fetch the first data item for this key, to see if it
 947          * exists and if it's a range.
 948          */
 949         rc = cursor->c_get( cursor, key, &data, DB_SET );
 950         err = "c_get";
 951         if ( rc == 0 ) {
 952                 if ( tmp != 0 ) {
 953                         /* Not a range, just delete it */
 954                         if (tmp != nid) {
 955                                 /* position to correct item */
 956                                 tmp = nid;
 957                                 rc = cursor->c_get( cursor, key, &data, DB_GET_BOTH );
 958                                 if ( rc != 0 ) {
 959                                         err = "c_get id";
 960                                         goto fail;
 961                                 }
 962                         }
 963                         rc = cursor->c_del( cursor, 0 );
 964                         if ( rc != 0 ) {
 965                                 err = "c_del id";
 966                                 goto fail;
 967                         }
 968                 } else {
 969                         /* It's a range, see if we need to rewrite
 970                          * the boundaries
 971                          */
 972                         data.data = &nlo;
 973                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 974                         if ( rc != 0 ) {
 975                                 err = "c_get lo";
 976                                 goto fail;
 977                         }
 978                         BDB_DISK2ID( &nlo, &lo );
 979                         data.data = &nhi;
 980                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 981                         if ( rc != 0 ) {
 982                                 err = "c_get hi";
 983                                 goto fail;
 984                         }
 985                         BDB_DISK2ID( &nhi, &hi );
 986                         if ( id == lo || id == hi ) {
 987                                 if ( id == lo ) {
 988                                         id++;
 989                                         lo = id;
 990                                 } else if ( id == hi ) {
 991                                         id--;
 992                                         hi = id;
 993                                 }
 994                                 if ( lo >= hi ) {
 995                                 /* The range has collapsed... */
 996                                         rc = db->del( db, tid, key, 0 );
 997                                         if ( rc != 0 ) {
 998                                                 err = "del";
 999                                                 goto fail;
1000                                         }
1001                                 } else {
1002                                         if ( id == lo ) {
1003                                                 /* reposition on lo slot */
1004                                                 data.data = &nlo;
1005                                                 cursor->c_get( cursor, key, &data, DB_PREV );
1006                                         }
1007                                         rc = cursor->c_del( cursor, 0 );
1008                                         if ( rc != 0 ) {
1009                                                 err = "c_del";
1010                                                 goto fail;
1011                                         }
1012                                 }
1013                                 if ( lo <= hi ) {
1014                                         BDB_ID2DISK( id, &nid );
1015                                         data.data = &nid;
1016                                         rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
1017                                         if ( rc != 0 ) {
1018                                                 err = "c_put lo/hi";
1019                                                 goto fail;
1020                                         }
1021                                 }
1022                         }
1023                 }
1024         } else {
1025                 /* initial c_get failed, nothing was done */
1026 fail:
1027                 if ( rc != DB_NOTFOUND ) {
1028                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
1029                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
1030                 }
1031                 cursor->c_close( cursor );
1032                 return rc;
1033         }
1034         rc = cursor->c_close( cursor );
1035         if( rc != 0 ) {
1036                 Debug( LDAP_DEBUG_ANY,
1037                         "=> bdb_idl_delete_key: c_close failed: %s (%d)\n",
1038                         db_strerror(rc), rc, 0 );
1039         }
1040
1041         return rc;
1042 }
1043
1044
1045 /*
1046  * idl_intersection - return a = a intersection b
1047  */
1048 int
1049 bdb_idl_intersection(
1050         ID *a,
1051         ID *b )
1052 {
1053         ID ida, idb;
1054         ID idmax, idmin;
1055         ID cursora = 0, cursorb = 0, cursorc;
1056         int swap = 0;
1057
1058         if ( BDB_IDL_IS_ZERO( a ) || BDB_IDL_IS_ZERO( b ) ) {
1059                 a[0] = 0;
1060                 return 0;
1061         }
1062
1063         idmin = IDL_MAX( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1064         idmax = IDL_MIN( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1065         if ( idmin > idmax ) {
1066                 a[0] = 0;
1067                 return 0;
1068         } else if ( idmin == idmax ) {
1069                 a[0] = 1;
1070                 a[1] = idmin;
1071                 return 0;
1072         }
1073
1074         if ( BDB_IDL_IS_RANGE( a ) ) {
1075                 if ( BDB_IDL_IS_RANGE(b) ) {
1076                 /* If both are ranges, just shrink the boundaries */
1077                         a[1] = idmin;
1078                         a[2] = idmax;
1079                         return 0;
1080                 } else {
1081                 /* Else swap so that b is the range, a is a list */
1082                         ID *tmp = a;
1083                         a = b;
1084                         b = tmp;
1085                         swap = 1;
1086                 }
1087         }
1088
1089         /* If a range completely covers the list, the result is
1090          * just the list. If idmin to idmax is contiguous, just
1091          * turn it into a range.
1092          */
1093         if ( BDB_IDL_IS_RANGE( b )
1094                 && BDB_IDL_FIRST( b ) <= BDB_IDL_FIRST( a )
1095                 && BDB_IDL_LAST( b ) >= BDB_IDL_LAST( a ) ) {
1096                 if (idmax - idmin + 1 == a[0])
1097                 {
1098                         a[0] = NOID;
1099                         a[1] = idmin;
1100                         a[2] = idmax;
1101                 }
1102                 goto done;
1103         }
1104
1105         /* Fine, do the intersection one element at a time.
1106          * First advance to idmin in both IDLs.
1107          */
1108         cursora = cursorb = idmin;
1109         ida = bdb_idl_first( a, &cursora );
1110         idb = bdb_idl_first( b, &cursorb );
1111         cursorc = 0;
1112
1113         while( ida <= idmax || idb <= idmax ) {
1114                 if( ida == idb ) {
1115                         a[++cursorc] = ida;
1116                         ida = bdb_idl_next( a, &cursora );
1117                         idb = bdb_idl_next( b, &cursorb );
1118                 } else if ( ida < idb ) {
1119                         ida = bdb_idl_next( a, &cursora );
1120                 } else {
1121                         idb = bdb_idl_next( b, &cursorb );
1122                 }
1123         }
1124         a[0] = cursorc;
1125 done:
1126         if (swap)
1127                 BDB_IDL_CPY( b, a );
1128
1129         return 0;
1130 }
1131
1132
1133 /*
1134  * idl_union - return a = a union b
1135  */
1136 int
1137 bdb_idl_union(
1138         ID      *a,
1139         ID      *b )
1140 {
1141         ID ida, idb;
1142         ID cursora = 0, cursorb = 0, cursorc;
1143
1144         if ( BDB_IDL_IS_ZERO( b ) ) {
1145                 return 0;
1146         }
1147
1148         if ( BDB_IDL_IS_ZERO( a ) ) {
1149                 BDB_IDL_CPY( a, b );
1150                 return 0;
1151         }
1152
1153         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ) {
1154 over:           ida = IDL_MIN( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1155                 idb = IDL_MAX( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1156                 a[0] = NOID;
1157                 a[1] = ida;
1158                 a[2] = idb;
1159                 return 0;
1160         }
1161
1162         ida = bdb_idl_first( a, &cursora );
1163         idb = bdb_idl_first( b, &cursorb );
1164
1165         cursorc = b[0];
1166
1167         /* The distinct elements of a are cat'd to b */
1168         while( ida != NOID || idb != NOID ) {
1169                 if ( ida < idb ) {
1170                         if( ++cursorc > BDB_IDL_UM_MAX ) {
1171                                 goto over;
1172                         }
1173                         b[cursorc] = ida;
1174                         ida = bdb_idl_next( a, &cursora );
1175
1176                 } else {
1177                         if ( ida == idb )
1178                                 ida = bdb_idl_next( a, &cursora );
1179                         idb = bdb_idl_next( b, &cursorb );
1180                 }
1181         }
1182
1183         /* b is copied back to a in sorted order */
1184         a[0] = cursorc;
1185         cursora = 1;
1186         cursorb = 1;
1187         cursorc = b[0]+1;
1188         while (cursorb <= b[0] || cursorc <= a[0]) {
1189                 if (cursorc > a[0])
1190                         idb = NOID;
1191                 else
1192                         idb = b[cursorc];
1193                 if (cursorb <= b[0] && b[cursorb] < idb)
1194                         a[cursora++] = b[cursorb++];
1195                 else {
1196                         a[cursora++] = idb;
1197                         cursorc++;
1198                 }
1199         }
1200
1201         return 0;
1202 }
1203
1204
1205 #if 0
1206 /*
1207  * bdb_idl_notin - return a intersection ~b (or a minus b)
1208  */
1209 int
1210 bdb_idl_notin(
1211         ID      *a,
1212         ID      *b,
1213         ID *ids )
1214 {
1215         ID ida, idb;
1216         ID cursora = 0, cursorb = 0;
1217
1218         if( BDB_IDL_IS_ZERO( a ) ||
1219                 BDB_IDL_IS_ZERO( b ) ||
1220                 BDB_IDL_IS_RANGE( b ) )
1221         {
1222                 BDB_IDL_CPY( ids, a );
1223                 return 0;
1224         }
1225
1226         if( BDB_IDL_IS_RANGE( a ) ) {
1227                 BDB_IDL_CPY( ids, a );
1228                 return 0;
1229         }
1230
1231         ida = bdb_idl_first( a, &cursora ),
1232         idb = bdb_idl_first( b, &cursorb );
1233
1234         ids[0] = 0;
1235
1236         while( ida != NOID ) {
1237                 if ( idb == NOID ) {
1238                         /* we could shortcut this */
1239                         ids[++ids[0]] = ida;
1240                         ida = bdb_idl_next( a, &cursora );
1241
1242                 } else if ( ida < idb ) {
1243                         ids[++ids[0]] = ida;
1244                         ida = bdb_idl_next( a, &cursora );
1245
1246                 } else if ( ida > idb ) {
1247                         idb = bdb_idl_next( b, &cursorb );
1248
1249                 } else {
1250                         ida = bdb_idl_next( a, &cursora );
1251                         idb = bdb_idl_next( b, &cursorb );
1252                 }
1253         }
1254
1255         return 0;
1256 }
1257 #endif
1258
1259 ID bdb_idl_first( ID *ids, ID *cursor )
1260 {
1261         ID pos;
1262
1263         if ( ids[0] == 0 ) {
1264                 *cursor = NOID;
1265                 return NOID;
1266         }
1267
1268         if ( BDB_IDL_IS_RANGE( ids ) ) {
1269                 if( *cursor < ids[1] ) {
1270                         *cursor = ids[1];
1271                 }
1272                 return *cursor;
1273         }
1274
1275         if ( *cursor == 0 )
1276                 pos = 1;
1277         else
1278                 pos = bdb_idl_search( ids, *cursor );
1279
1280         if( pos > ids[0] ) {
1281                 return NOID;
1282         }
1283
1284         *cursor = pos;
1285         return ids[pos];
1286 }
1287
1288 ID bdb_idl_next( ID *ids, ID *cursor )
1289 {
1290         if ( BDB_IDL_IS_RANGE( ids ) ) {
1291                 if( ids[2] < ++(*cursor) ) {
1292                         return NOID;
1293                 }
1294                 return *cursor;
1295         }
1296
1297         if ( ++(*cursor) <= ids[0] ) {
1298                 return ids[*cursor];
1299         }
1300
1301         return NOID;
1302 }
1303
1304 #ifdef BDB_HIER
1305
1306 /* Add one ID to an unsorted list. We ensure that the first element is the
1307  * minimum and the last element is the maximum, for fast range compaction.
1308  *   this means IDLs up to length 3 are always sorted...
1309  */
1310 int bdb_idl_append_one( ID *ids, ID id )
1311 {
1312         if (BDB_IDL_IS_RANGE( ids )) {
1313                 /* if already in range, treat as a dup */
1314                 if (id >= BDB_IDL_FIRST(ids) && id <= BDB_IDL_LAST(ids))
1315                         return -1;
1316                 if (id < BDB_IDL_FIRST(ids))
1317                         ids[1] = id;
1318                 else if (id > BDB_IDL_LAST(ids))
1319                         ids[2] = id;
1320                 return 0;
1321         }
1322         if ( ids[0] ) {
1323                 ID tmp;
1324
1325                 if (id < ids[1]) {
1326                         tmp = ids[1];
1327                         ids[1] = id;
1328                         id = tmp;
1329                 }
1330                 if ( ids[0] > 1 && id < ids[ids[0]] ) {
1331                         tmp = ids[ids[0]];
1332                         ids[ids[0]] = id;
1333                         id = tmp;
1334                 }
1335         }
1336         ids[0]++;
1337         if ( ids[0] >= BDB_IDL_UM_MAX ) {
1338                 ids[0] = NOID;
1339                 ids[2] = id;
1340         } else {
1341                 ids[ids[0]] = id;
1342         }
1343         return 0;
1344 }
1345
1346 /* Append sorted list b to sorted list a. The result is unsorted but
1347  * a[1] is the min of the result and a[a[0]] is the max.
1348  */
1349 int bdb_idl_append( ID *a, ID *b )
1350 {
1351         ID ida, idb, tmp, swap = 0;
1352
1353         if ( BDB_IDL_IS_ZERO( b ) ) {
1354                 return 0;
1355         }
1356
1357         if ( BDB_IDL_IS_ZERO( a ) ) {
1358                 BDB_IDL_CPY( a, b );
1359                 return 0;
1360         }
1361
1362         ida = BDB_IDL_LAST( a );
1363         idb = BDB_IDL_LAST( b );
1364         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ||
1365                 a[0] + b[0] >= BDB_IDL_UM_MAX ) {
1366                 a[2] = IDL_MAX( ida, idb );
1367                 a[1] = IDL_MIN( a[1], b[1] );
1368                 a[0] = NOID;
1369                 return 0;
1370         }
1371
1372         if ( b[0] > 1 && ida > idb ) {
1373                 swap = idb;
1374                 a[a[0]] = idb;
1375                 b[b[0]] = ida;
1376         }
1377
1378         if ( b[1] < a[1] ) {
1379                 tmp = a[1];
1380                 a[1] = b[1];
1381         } else {
1382                 tmp = b[1];
1383         }
1384         a[0]++;
1385         a[a[0]] = tmp;
1386
1387         if ( b[0] > 1 ) {
1388                 int i = b[0] - 1;
1389                 AC_MEMCPY(a+a[0]+1, b+2, i * sizeof(ID));
1390                 a[0] += i;
1391         }
1392         if ( swap ) {
1393                 b[b[0]] = swap;
1394         }
1395         return 0;
1396 }
1397
1398 #if 1
1399
1400 /* Quicksort + Insertion sort for small arrays */
1401
1402 #define SMALL   8
1403 #define SWAP(a,b)       itmp=(a);(a)=(b);(b)=itmp
1404
1405 void
1406 bdb_idl_sort( ID *ids, ID *tmp )
1407 {
1408         int *istack = (int *)tmp;
1409         int i,j,k,l,ir,jstack;
1410         ID a, itmp;
1411
1412         if ( BDB_IDL_IS_RANGE( ids ))
1413                 return;
1414
1415         ir = ids[0];
1416         l = 1;
1417         jstack = 0;
1418         for(;;) {
1419                 if (ir - l < SMALL) {   /* Insertion sort */
1420                         for (j=l+1;j<=ir;j++) {
1421                                 a = ids[j];
1422                                 for (i=j-1;i>=1;i--) {
1423                                         if (ids[i] <= a) break;
1424                                         ids[i+1] = ids[i];
1425                                 }
1426                                 ids[i+1] = a;
1427                         }
1428                         if (jstack == 0) break;
1429                         ir = istack[jstack--];
1430                         l = istack[jstack--];
1431                 } else {
1432                         k = (l + ir) >> 1;      /* Choose median of left, center, right */
1433                         SWAP(ids[k], ids[l+1]);
1434                         if (ids[l] > ids[ir]) {
1435                                 SWAP(ids[l], ids[ir]);
1436                         }
1437                         if (ids[l+1] > ids[ir]) {
1438                                 SWAP(ids[l+1], ids[ir]);
1439                         }
1440                         if (ids[l] > ids[l+1]) {
1441                                 SWAP(ids[l], ids[l+1]);
1442                         }
1443                         i = l+1;
1444                         j = ir;
1445                         a = ids[l+1];
1446                         for(;;) {
1447                                 do i++; while(ids[i] < a);
1448                                 do j--; while(ids[j] > a);
1449                                 if (j < i) break;
1450                                 SWAP(ids[i],ids[j]);
1451                         }
1452                         ids[l+1] = ids[j];
1453                         ids[j] = a;
1454                         jstack += 2;
1455                         if (ir-i+1 >= j-1) {
1456                                 istack[jstack] = ir;
1457                                 istack[jstack-1] = i;
1458                                 ir = j-1;
1459                         } else {
1460                                 istack[jstack] = j-1;
1461                                 istack[jstack-1] = l;
1462                                 l = i;
1463                         }
1464                 }
1465         }
1466 }
1467
1468 #else
1469
1470 /* 8 bit Radix sort + insertion sort
1471  *
1472  * based on code from http://www.cubic.org/docs/radix.htm
1473  * with improvements by mbackes@symas.com and hyc@symas.com
1474  *
1475  * This code is O(n) but has a relatively high constant factor. For lists
1476  * up to ~50 Quicksort is slightly faster; up to ~100 they are even.
1477  * Much faster than quicksort for lists longer than ~100. Insertion
1478  * sort is actually superior for lists <50.
1479  */
1480
1481 #define BUCKETS (1<<8)
1482 #define SMALL   50
1483
1484 void
1485 bdb_idl_sort( ID *ids, ID *tmp )
1486 {
1487         int count, soft_limit, phase = 0, size = ids[0];
1488         ID *idls[2];
1489         unsigned char *maxv = (unsigned char *)&ids[size];
1490
1491         if ( BDB_IDL_IS_RANGE( ids ))
1492                 return;
1493
1494         /* Use insertion sort for small lists */
1495         if ( size <= SMALL ) {
1496                 int i,j;
1497                 ID a;
1498
1499                 for (j=1;j<=size;j++) {
1500                         a = ids[j];
1501                         for (i=j-1;i>=1;i--) {
1502                                 if (ids[i] <= a) break;
1503                                 ids[i+1] = ids[i];
1504                         }
1505                         ids[i+1] = a;
1506                 }
1507                 return;
1508         }
1509
1510         tmp[0] = size;
1511         idls[0] = ids;
1512         idls[1] = tmp;
1513
1514 #if BYTE_ORDER == BIG_ENDIAN
1515     for (soft_limit = 0; !maxv[soft_limit]; soft_limit++);
1516 #else
1517     for (soft_limit = sizeof(ID)-1; !maxv[soft_limit]; soft_limit--);
1518 #endif
1519
1520         for (
1521 #if BYTE_ORDER == BIG_ENDIAN
1522         count = sizeof(ID)-1; count >= soft_limit; --count
1523 #else
1524         count = 0; count <= soft_limit; ++count
1525 #endif
1526         ) {
1527                 unsigned int num[BUCKETS], * np, n, sum;
1528                 int i;
1529         ID *sp, *source, *dest;
1530         unsigned char *bp, *source_start;
1531
1532                 source = idls[phase]+1;
1533                 dest = idls[phase^1]+1;
1534                 source_start =  ((unsigned char *) source) + count;
1535
1536         np = num;
1537         for ( i = BUCKETS; i > 0; --i ) *np++ = 0;
1538
1539                 /* count occurences of every byte value */
1540                 bp = source_start;
1541         for ( i = size; i > 0; --i, bp += sizeof(ID) )
1542                                 num[*bp]++;
1543
1544                 /* transform count into index by summing elements and storing
1545                  * into same array
1546                  */
1547         sum = 0;
1548         np = num;
1549         for ( i = BUCKETS; i > 0; --i ) {
1550                 n = *np;
1551                 *np++ = sum;
1552                 sum += n;
1553         }
1554
1555                 /* fill dest with the right values in the right place */
1556                 bp = source_start;
1557         sp = source;
1558         for ( i = size; i > 0; --i, bp += sizeof(ID) ) {
1559                 np = num + *bp;
1560                 dest[*np] = *sp++;
1561                 ++(*np);
1562         }
1563                 phase ^= 1;
1564         }
1565
1566         /* copy back from temp if needed */
1567         if ( phase ) {
1568                 ids++; tmp++;
1569                 for ( count = 0; count < size; ++count )
1570                         *ids++ = *tmp++;
1571         }
1572 }
1573 #endif  /* Quick vs Radix */
1574
1575 #endif  /* BDB_HIER */