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         DB_TXN          *tid,
 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, tid, &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         } else {
 563                 cursor = *saved_cursor;
 564         }
 565
 566         /* If this is a LE lookup, save original key so we can determine
 567          * when to stop. If this is a GE lookup, save the key since it
 568          * will be overwritten.
 569          */
 570         if ( get_flag == LDAP_FILTER_LE || get_flag == LDAP_FILTER_GE ) {
 571                 DBTzero( &key2 );
 572                 key2.flags = DB_DBT_USERMEM;
 573                 key2.ulen = sizeof(keybuf);
 574                 key2.data = keybuf;
 575                 key2.size = key->size;
 576                 AC_MEMCPY( keybuf, key->data, key->size );
 577                 kptr = &key2;
 578         } else {
 579                 kptr = key;
 580         }
 581         len = key->size;
 582         rc = cursor->c_get( cursor, kptr, &data, flags | opflag );
 583
 584         /* skip presence key on range inequality lookups */
 585         while (rc == 0 && kptr->size != len) {
 586                 rc = cursor->c_get( cursor, kptr, &data, flags | DB_NEXT_NODUP );
 587         }
 588         /* If we're doing a LE compare and the new key is greater than
 589          * our search key, we're done
 590          */
 591         if (rc == 0 && get_flag == LDAP_FILTER_LE && memcmp( kptr->data,
 592                 key->data, key->size ) > 0 ) {
 593                 rc = DB_NOTFOUND;
 594         }
 595         if (rc == 0) {
 596                 i = ids;
 597                 while (rc == 0) {
 598                         u_int8_t *j;
 599
 600                         DB_MULTIPLE_INIT( ptr, &data );
 601                         while (ptr) {
 602                                 DB_MULTIPLE_NEXT(ptr, &data, j, len);
 603                                 if (j) {
 604                                         ++i;
 605                                         BDB_DISK2ID( j, i );
 606                                 }
 607                         }
 608                         rc = cursor->c_get( cursor, key, &data, flags | DB_NEXT_DUP );
 609                 }
 610                 if ( rc == DB_NOTFOUND ) rc = 0;
 611                 ids[0] = i - ids;
 612                 /* On disk, a range is denoted by 0 in the first element */
 613                 if (ids[1] == 0) {
 614                         if (ids[0] != BDB_IDL_RANGE_SIZE) {
 615                                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 616                                         "range size mismatch: expected %d, got %ld\n",
 617                                         BDB_IDL_RANGE_SIZE, ids[0], 0 );
 618                                 cursor->c_close( cursor );
 619                                 return -1;
 620                         }
 621                         BDB_IDL_RANGE( ids, ids[2], ids[3] );
 622                 }
 623                 data.size = BDB_IDL_SIZEOF(ids);
 624         }
 625
 626         if ( saved_cursor && rc == 0 ) {
 627                 if ( !*saved_cursor )
 628                         *saved_cursor = cursor;
 629                 rc2 = 0;
 630         }
 631         else
 632                 rc2 = cursor->c_close( cursor );
 633         if (rc2) {
 634                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 635                         "close failed: %s (%d)\n", db_strerror(rc2), rc2, 0 );
 636                 return rc2;
 637         }
 638
 639         if( rc == DB_NOTFOUND ) {
 640                 return rc;
 641
 642         } else if( rc != 0 ) {
 643                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 644                         "get failed: %s (%d)\n",
 645                         db_strerror(rc), rc, 0 );
 646                 return rc;
 647
 648         } else if ( data.size == 0 || data.size % sizeof( ID ) ) {
 649                 /* size not multiple of ID size */
 650                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 651                         "odd size: expected %ld multiple, got %ld\n",
 652                         (long) sizeof( ID ), (long) data.size, 0 );
 653                 return -1;
 654
 655         } else if ( data.size != BDB_IDL_SIZEOF(ids) ) {
 656                 /* size mismatch */
 657                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_fetch_key: "
 658                         "get size mismatch: expected %ld, got %ld\n",
 659                         (long) ((1 + ids[0]) * sizeof( ID )), (long) data.size, 0 );
 660                 return -1;
 661         }
 662
 663         if ( bdb->bi_idl_cache_max_size ) {
 664                 bdb_idl_cache_put( bdb, db, key, ids, rc );
 665         }
 666
 667         return rc;
 668 }
 669
 670
 671 int
 672 bdb_idl_insert_key(
 673         BackendDB       *be,
 674         DB                      *db,
 675         DB_TXN          *tid,
 676         DBT                     *key,
 677         ID                      id )
 678 {
 679         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 680         int     rc;
 681         DBT data;
 682         DBC *cursor;
 683         ID lo, hi, nlo, nhi, nid;
 684         char *err;
 685
 686         {
 687                 char buf[16];
 688                 Debug( LDAP_DEBUG_ARGS,
 689                         "bdb_idl_insert_key: %lx %s\n",
 690                         (long) id, bdb_show_key( key, buf ), 0 );
 691         }
 692
 693         assert( id != NOID );
 694
 695         if ( bdb->bi_idl_cache_size ) {
 696                 bdb_idl_cache_del( bdb, db, key );
 697         }
 698
 699         DBTzero( &data );
 700         data.size = sizeof( ID );
 701         data.ulen = data.size;
 702         data.flags = DB_DBT_USERMEM;
 703
 704         BDB_ID2DISK( id, &nid );
 705
 706         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 707         if ( rc != 0 ) {
 708                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 709                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 710                 return rc;
 711         }
 712         data.data = &nlo;
 713         /* Fetch the first data item for this key, to see if it
 714          * exists and if it's a range.
 715          */
 716         rc = cursor->c_get( cursor, key, &data, DB_SET );
 717         err = "c_get";
 718         if ( rc == 0 ) {
 719                 if ( nlo != 0 ) {
 720                         /* not a range, count the number of items */
 721                         db_recno_t count;
 722                         rc = cursor->c_count( cursor, &count, 0 );
 723                         if ( rc != 0 ) {
 724                                 err = "c_count";
 725                                 goto fail;
 726                         }
 727                         if ( count >= BDB_IDL_DB_MAX ) {
 728                         /* No room, convert to a range */
 729                                 DBT key2 = *key;
 730                                 db_recno_t i;
 731
 732                                 key2.dlen = key2.ulen;
 733                                 key2.flags |= DB_DBT_PARTIAL;
 734
 735                                 BDB_DISK2ID( &nlo, &lo );
 736                                 data.data = &nhi;
 737
 738                                 rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_NODUP );
 739                                 if ( rc != 0 && rc != DB_NOTFOUND ) {
 740                                         err = "c_get next_nodup";
 741                                         goto fail;
 742                                 }
 743                                 if ( rc == DB_NOTFOUND ) {
 744                                         rc = cursor->c_get( cursor, key, &data, DB_LAST );
 745                                         if ( rc != 0 ) {
 746                                                 err = "c_get last";
 747                                                 goto fail;
 748                                         }
 749                                 } else {
 750                                         rc = cursor->c_get( cursor, key, &data, DB_PREV );
 751                                         if ( rc != 0 ) {
 752                                                 err = "c_get prev";
 753                                                 goto fail;
 754                                         }
 755                                 }
 756                                 BDB_DISK2ID( &nhi, &hi );
 757                                 /* Update hi/lo if needed, then delete all the items
 758                                  * between lo and hi
 759                                  */
 760                                 if ( id < lo ) {
 761                                         lo = id;
 762                                         nlo = nid;
 763                                 } else if ( id > hi ) {
 764                                         hi = id;
 765                                         nhi = nid;
 766                                 }
 767                                 data.data = &nid;
 768                                 /* Don't fetch anything, just position cursor */
 769                                 data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 770                                 data.dlen = data.ulen = 0;
 771                                 rc = cursor->c_get( cursor, key, &data, DB_SET );
 772                                 if ( rc != 0 ) {
 773                                         err = "c_get 2";
 774                                         goto fail;
 775                                 }
 776                                 rc = cursor->c_del( cursor, 0 );
 777                                 if ( rc != 0 ) {
 778                                         err = "c_del range1";
 779                                         goto fail;
 780                                 }
 781                                 /* Delete all the records */
 782                                 for ( i=1; i<count; i++ ) {
 783                                         rc = cursor->c_get( cursor, &key2, &data, DB_NEXT_DUP );
 784                                         if ( rc != 0 ) {
 785                                                 err = "c_get next_dup";
 786                                                 goto fail;
 787                                         }
 788                                         rc = cursor->c_del( cursor, 0 );
 789                                         if ( rc != 0 ) {
 790                                                 err = "c_del range";
 791                                                 goto fail;
 792                                         }
 793                                 }
 794                                 /* Store the range marker */
 795                                 data.size = data.ulen = sizeof(ID);
 796                                 data.flags = DB_DBT_USERMEM;
 797                                 nid = 0;
 798                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 799                                 if ( rc != 0 ) {
 800                                         err = "c_put range";
 801                                         goto fail;
 802                                 }
 803                                 nid = nlo;
 804                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 805                                 if ( rc != 0 ) {
 806                                         err = "c_put lo";
 807                                         goto fail;
 808                                 }
 809                                 nid = nhi;
 810                                 rc = cursor->c_put( cursor, key, &data, DB_KEYLAST );
 811                                 if ( rc != 0 ) {
 812                                         err = "c_put hi";
 813                                         goto fail;
 814                                 }
 815                         } else {
 816                         /* There's room, just store it */
 817                                 goto put1;
 818                         }
 819                 } else {
 820                         /* It's a range, see if we need to rewrite
 821                          * the boundaries
 822                          */
 823                         hi = id;
 824                         data.data = &nlo;
 825                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 826                         if ( rc != 0 ) {
 827                                 err = "c_get lo";
 828                                 goto fail;
 829                         }
 830                         BDB_DISK2ID( &nlo, &lo );
 831                         if ( id > lo ) {
 832                                 data.data = &nhi;
 833                                 rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 834                                 if ( rc != 0 ) {
 835                                         err = "c_get hi";
 836                                         goto fail;
 837                                 }
 838                                 BDB_DISK2ID( &nhi, &hi );
 839                         }
 840                         if ( id < lo || id > hi ) {
 841                                 /* Delete the current lo/hi */
 842                                 rc = cursor->c_del( cursor, 0 );
 843                                 if ( rc != 0 ) {
 844                                         err = "c_del";
 845                                         goto fail;
 846                                 }
 847                                 data.data = &nid;
 848                                 rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 849                                 if ( rc != 0 ) {
 850                                         err = "c_put lo/hi";
 851                                         goto fail;
 852                                 }
 853                         }
 854                 }
 855         } else if ( rc == DB_NOTFOUND ) {
 856 put1:           data.data = &nid;
 857                 rc = cursor->c_put( cursor, key, &data, DB_NODUPDATA );
 858                 /* Don't worry if it's already there */
 859                 if ( rc != 0 && rc != DB_KEYEXIST ) {
 860                         err = "c_put id";
 861                         goto fail;
 862                 }
 863         } else {
 864                 /* initial c_get failed, nothing was done */
 865 fail:
 866                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 867                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
 868                 cursor->c_close( cursor );
 869                 return rc;
 870         }
 871         rc = cursor->c_close( cursor );
 872         if( rc != 0 ) {
 873                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_insert_key: "
 874                         "c_close failed: %s (%d)\n",
 875                         db_strerror(rc), rc, 0 );
 876         }
 877         return rc;
 878 }
 879
 880 int
 881 bdb_idl_delete_key(
 882         BackendDB       *be,
 883         DB                      *db,
 884         DB_TXN          *tid,
 885         DBT                     *key,
 886         ID                      id )
 887 {
 888         struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 889         int     rc;
 890         DBT data;
 891         DBC *cursor;
 892         ID lo, hi, tmp, nid, nlo, nhi;
 893         char *err;
 894
 895         {
 896                 char buf[16];
 897                 Debug( LDAP_DEBUG_ARGS,
 898                         "bdb_idl_delete_key: %lx %s\n",
 899                         (long) id, bdb_show_key( key, buf ), 0 );
 900         }
 901         assert( id != NOID );
 902
 903         if ( bdb->bi_idl_cache_max_size ) {
 904                 bdb_idl_cache_del( bdb, db, key );
 905         }
 906
 907         BDB_ID2DISK( id, &nid );
 908
 909         DBTzero( &data );
 910         data.data = &tmp;
 911         data.size = sizeof( id );
 912         data.ulen = data.size;
 913         data.flags = DB_DBT_USERMEM;
 914
 915         rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
 916         if ( rc != 0 ) {
 917                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
 918                         "cursor failed: %s (%d)\n", db_strerror(rc), rc, 0 );
 919                 return rc;
 920         }
 921         /* Fetch the first data item for this key, to see if it
 922          * exists and if it's a range.
 923          */
 924         rc = cursor->c_get( cursor, key, &data, DB_SET );
 925         err = "c_get";
 926         if ( rc == 0 ) {
 927                 if ( tmp != 0 ) {
 928                         /* Not a range, just delete it */
 929                         if (tmp != nid) {
 930                                 /* position to correct item */
 931                                 tmp = nid;
 932                                 rc = cursor->c_get( cursor, key, &data, DB_GET_BOTH );
 933                                 if ( rc != 0 ) {
 934                                         err = "c_get id";
 935                                         goto fail;
 936                                 }
 937                         }
 938                         rc = cursor->c_del( cursor, 0 );
 939                         if ( rc != 0 ) {
 940                                 err = "c_del id";
 941                                 goto fail;
 942                         }
 943                 } else {
 944                         /* It's a range, see if we need to rewrite
 945                          * the boundaries
 946                          */
 947                         data.data = &nlo;
 948                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 949                         if ( rc != 0 ) {
 950                                 err = "c_get lo";
 951                                 goto fail;
 952                         }
 953                         BDB_DISK2ID( &nlo, &lo );
 954                         data.data = &nhi;
 955                         rc = cursor->c_get( cursor, key, &data, DB_NEXT_DUP );
 956                         if ( rc != 0 ) {
 957                                 err = "c_get hi";
 958                                 goto fail;
 959                         }
 960                         BDB_DISK2ID( &nhi, &hi );
 961                         if ( id == lo || id == hi ) {
 962                                 if ( id == lo ) {
 963                                         id++;
 964                                         lo = id;
 965                                 } else if ( id == hi ) {
 966                                         id--;
 967                                         hi = id;
 968                                 }
 969                                 if ( lo >= hi ) {
 970                                 /* The range has collapsed... */
 971                                         rc = db->del( db, tid, key, 0 );
 972                                         if ( rc != 0 ) {
 973                                                 err = "del";
 974                                                 goto fail;
 975                                         }
 976                                 } else {
 977                                         if ( id == lo ) {
 978                                                 /* reposition on lo slot */
 979                                                 data.data = &nlo;
 980                                                 cursor->c_get( cursor, key, &data, DB_PREV );
 981                                         }
 982                                         rc = cursor->c_del( cursor, 0 );
 983                                         if ( rc != 0 ) {
 984                                                 err = "c_del";
 985                                                 goto fail;
 986                                         }
 987                                 }
 988                                 if ( lo <= hi ) {
 989                                         BDB_ID2DISK( id, &nid );
 990                                         data.data = &nid;
 991                                         rc = cursor->c_put( cursor, key, &data, DB_KEYFIRST );
 992                                         if ( rc != 0 ) {
 993                                                 err = "c_put lo/hi";
 994                                                 goto fail;
 995                                         }
 996                                 }
 997                         }
 998                 }
 999         } else {
1000                 /* initial c_get failed, nothing was done */
1001 fail:
1002                 if ( rc != DB_NOTFOUND ) {
1003                 Debug( LDAP_DEBUG_ANY, "=> bdb_idl_delete_key: "
1004                         "%s failed: %s (%d)\n", err, db_strerror(rc), rc );
1005                 }
1006                 cursor->c_close( cursor );
1007                 return rc;
1008         }
1009         rc = cursor->c_close( cursor );
1010         if( rc != 0 ) {
1011                 Debug( LDAP_DEBUG_ANY,
1012                         "=> bdb_idl_delete_key: c_close failed: %s (%d)\n",
1013                         db_strerror(rc), rc, 0 );
1014         }
1015
1016         return rc;
1017 }
1018
1019
1020 /*
1021  * idl_intersection - return a = a intersection b
1022  */
1023 int
1024 bdb_idl_intersection(
1025         ID *a,
1026         ID *b )
1027 {
1028         ID ida, idb;
1029         ID idmax, idmin;
1030         ID cursora = 0, cursorb = 0, cursorc;
1031         int swap = 0;
1032
1033         if ( BDB_IDL_IS_ZERO( a ) || BDB_IDL_IS_ZERO( b ) ) {
1034                 a[0] = 0;
1035                 return 0;
1036         }
1037
1038         idmin = IDL_MAX( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1039         idmax = IDL_MIN( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1040         if ( idmin > idmax ) {
1041                 a[0] = 0;
1042                 return 0;
1043         } else if ( idmin == idmax ) {
1044                 a[0] = 1;
1045                 a[1] = idmin;
1046                 return 0;
1047         }
1048
1049         if ( BDB_IDL_IS_RANGE( a ) ) {
1050                 if ( BDB_IDL_IS_RANGE(b) ) {
1051                 /* If both are ranges, just shrink the boundaries */
1052                         a[1] = idmin;
1053                         a[2] = idmax;
1054                         return 0;
1055                 } else {
1056                 /* Else swap so that b is the range, a is a list */
1057                         ID *tmp = a;
1058                         a = b;
1059                         b = tmp;
1060                         swap = 1;
1061                 }
1062         }
1063
1064         /* If a range completely covers the list, the result is
1065          * just the list. If idmin to idmax is contiguous, just
1066          * turn it into a range.
1067          */
1068         if ( BDB_IDL_IS_RANGE( b )
1069                 && BDB_IDL_FIRST( b ) <= BDB_IDL_FIRST( a )
1070                 && BDB_IDL_LAST( b ) >= BDB_IDL_LAST( a ) ) {
1071                 if (idmax - idmin + 1 == a[0])
1072                 {
1073                         a[0] = NOID;
1074                         a[1] = idmin;
1075                         a[2] = idmax;
1076                 }
1077                 goto done;
1078         }
1079
1080         /* Fine, do the intersection one element at a time.
1081          * First advance to idmin in both IDLs.
1082          */
1083         cursora = cursorb = idmin;
1084         ida = bdb_idl_first( a, &cursora );
1085         idb = bdb_idl_first( b, &cursorb );
1086         cursorc = 0;
1087
1088         while( ida <= idmax || idb <= idmax ) {
1089                 if( ida == idb ) {
1090                         a[++cursorc] = ida;
1091                         ida = bdb_idl_next( a, &cursora );
1092                         idb = bdb_idl_next( b, &cursorb );
1093                 } else if ( ida < idb ) {
1094                         ida = bdb_idl_next( a, &cursora );
1095                 } else {
1096                         idb = bdb_idl_next( b, &cursorb );
1097                 }
1098         }
1099         a[0] = cursorc;
1100 done:
1101         if (swap)
1102                 BDB_IDL_CPY( b, a );
1103
1104         return 0;
1105 }
1106
1107
1108 /*
1109  * idl_union - return a = a union b
1110  */
1111 int
1112 bdb_idl_union(
1113         ID      *a,
1114         ID      *b )
1115 {
1116         ID ida, idb;
1117         ID cursora = 0, cursorb = 0, cursorc;
1118
1119         if ( BDB_IDL_IS_ZERO( b ) ) {
1120                 return 0;
1121         }
1122
1123         if ( BDB_IDL_IS_ZERO( a ) ) {
1124                 BDB_IDL_CPY( a, b );
1125                 return 0;
1126         }
1127
1128         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ) {
1129 over:           ida = IDL_MIN( BDB_IDL_FIRST(a), BDB_IDL_FIRST(b) );
1130                 idb = IDL_MAX( BDB_IDL_LAST(a), BDB_IDL_LAST(b) );
1131                 a[0] = NOID;
1132                 a[1] = ida;
1133                 a[2] = idb;
1134                 return 0;
1135         }
1136
1137         ida = bdb_idl_first( a, &cursora );
1138         idb = bdb_idl_first( b, &cursorb );
1139
1140         cursorc = b[0];
1141
1142         /* The distinct elements of a are cat'd to b */
1143         while( ida != NOID || idb != NOID ) {
1144                 if ( ida < idb ) {
1145                         if( ++cursorc > BDB_IDL_UM_MAX ) {
1146                                 goto over;
1147                         }
1148                         b[cursorc] = ida;
1149                         ida = bdb_idl_next( a, &cursora );
1150
1151                 } else {
1152                         if ( ida == idb )
1153                                 ida = bdb_idl_next( a, &cursora );
1154                         idb = bdb_idl_next( b, &cursorb );
1155                 }
1156         }
1157
1158         /* b is copied back to a in sorted order */
1159         a[0] = cursorc;
1160         cursora = 1;
1161         cursorb = 1;
1162         cursorc = b[0]+1;
1163         while (cursorb <= b[0] || cursorc <= a[0]) {
1164                 if (cursorc > a[0])
1165                         idb = NOID;
1166                 else
1167                         idb = b[cursorc];
1168                 if (cursorb <= b[0] && b[cursorb] < idb)
1169                         a[cursora++] = b[cursorb++];
1170                 else {
1171                         a[cursora++] = idb;
1172                         cursorc++;
1173                 }
1174         }
1175
1176         return 0;
1177 }
1178
1179
1180 #if 0
1181 /*
1182  * bdb_idl_notin - return a intersection ~b (or a minus b)
1183  */
1184 int
1185 bdb_idl_notin(
1186         ID      *a,
1187         ID      *b,
1188         ID *ids )
1189 {
1190         ID ida, idb;
1191         ID cursora = 0, cursorb = 0;
1192
1193         if( BDB_IDL_IS_ZERO( a ) ||
1194                 BDB_IDL_IS_ZERO( b ) ||
1195                 BDB_IDL_IS_RANGE( b ) )
1196         {
1197                 BDB_IDL_CPY( ids, a );
1198                 return 0;
1199         }
1200
1201         if( BDB_IDL_IS_RANGE( a ) ) {
1202                 BDB_IDL_CPY( ids, a );
1203                 return 0;
1204         }
1205
1206         ida = bdb_idl_first( a, &cursora ),
1207         idb = bdb_idl_first( b, &cursorb );
1208
1209         ids[0] = 0;
1210
1211         while( ida != NOID ) {
1212                 if ( idb == NOID ) {
1213                         /* we could shortcut this */
1214                         ids[++ids[0]] = ida;
1215                         ida = bdb_idl_next( a, &cursora );
1216
1217                 } else if ( ida < idb ) {
1218                         ids[++ids[0]] = ida;
1219                         ida = bdb_idl_next( a, &cursora );
1220
1221                 } else if ( ida > idb ) {
1222                         idb = bdb_idl_next( b, &cursorb );
1223
1224                 } else {
1225                         ida = bdb_idl_next( a, &cursora );
1226                         idb = bdb_idl_next( b, &cursorb );
1227                 }
1228         }
1229
1230         return 0;
1231 }
1232 #endif
1233
1234 ID bdb_idl_first( ID *ids, ID *cursor )
1235 {
1236         ID pos;
1237
1238         if ( ids[0] == 0 ) {
1239                 *cursor = NOID;
1240                 return NOID;
1241         }
1242
1243         if ( BDB_IDL_IS_RANGE( ids ) ) {
1244                 if( *cursor < ids[1] ) {
1245                         *cursor = ids[1];
1246                 }
1247                 return *cursor;
1248         }
1249
1250         if ( *cursor == 0 )
1251                 pos = 1;
1252         else
1253                 pos = bdb_idl_search( ids, *cursor );
1254
1255         if( pos > ids[0] ) {
1256                 return NOID;
1257         }
1258
1259         *cursor = pos;
1260         return ids[pos];
1261 }
1262
1263 ID bdb_idl_next( ID *ids, ID *cursor )
1264 {
1265         if ( BDB_IDL_IS_RANGE( ids ) ) {
1266                 if( ids[2] < ++(*cursor) ) {
1267                         return NOID;
1268                 }
1269                 return *cursor;
1270         }
1271
1272         if ( ++(*cursor) <= ids[0] ) {
1273                 return ids[*cursor];
1274         }
1275
1276         return NOID;
1277 }
1278
1279 #ifdef BDB_HIER
1280
1281 /* Add one ID to an unsorted list. We ensure that the first element is the
1282  * minimum and the last element is the maximum, for fast range compaction.
1283  *   this means IDLs up to length 3 are always sorted...
1284  */
1285 int bdb_idl_append_one( ID *ids, ID id )
1286 {
1287         if (BDB_IDL_IS_RANGE( ids )) {
1288                 /* if already in range, treat as a dup */
1289                 if (id >= BDB_IDL_FIRST(ids) && id <= BDB_IDL_LAST(ids))
1290                         return -1;
1291                 if (id < BDB_IDL_FIRST(ids))
1292                         ids[1] = id;
1293                 else if (id > BDB_IDL_LAST(ids))
1294                         ids[2] = id;
1295                 return 0;
1296         }
1297         if ( ids[0] ) {
1298                 ID tmp;
1299
1300                 if (id < ids[1]) {
1301                         tmp = ids[1];
1302                         ids[1] = id;
1303                         id = tmp;
1304                 }
1305                 if ( ids[0] > 1 && id < ids[ids[0]] ) {
1306                         tmp = ids[ids[0]];
1307                         ids[ids[0]] = id;
1308                         id = tmp;
1309                 }
1310         }
1311         ids[0]++;
1312         if ( ids[0] >= BDB_IDL_UM_MAX ) {
1313                 ids[0] = NOID;
1314                 ids[2] = id;
1315         } else {
1316                 ids[ids[0]] = id;
1317         }
1318         return 0;
1319 }
1320
1321 /* Append sorted list b to sorted list a. The result is unsorted but
1322  * a[1] is the min of the result and a[a[0]] is the max.
1323  */
1324 int bdb_idl_append( ID *a, ID *b )
1325 {
1326         ID ida, idb, tmp, swap = 0;
1327
1328         if ( BDB_IDL_IS_ZERO( b ) ) {
1329                 return 0;
1330         }
1331
1332         if ( BDB_IDL_IS_ZERO( a ) ) {
1333                 BDB_IDL_CPY( a, b );
1334                 return 0;
1335         }
1336
1337         ida = BDB_IDL_LAST( a );
1338         idb = BDB_IDL_LAST( b );
1339         if ( BDB_IDL_IS_RANGE( a ) || BDB_IDL_IS_RANGE(b) ||
1340                 a[0] + b[0] >= BDB_IDL_UM_MAX ) {
1341                 a[2] = IDL_MAX( ida, idb );
1342                 a[1] = IDL_MIN( a[1], b[1] );
1343                 a[0] = NOID;
1344                 return 0;
1345         }
1346
1347         if ( b[0] > 1 && ida > idb ) {
1348                 swap = idb;
1349                 a[a[0]] = idb;
1350                 b[b[0]] = ida;
1351         }
1352
1353         if ( b[1] < a[1] ) {
1354                 tmp = a[1];
1355                 a[1] = b[1];
1356         } else {
1357                 tmp = b[1];
1358         }
1359         a[0]++;
1360         a[a[0]] = tmp;
1361
1362         if ( b[0] > 1 ) {
1363                 int i = b[0] - 1;
1364                 AC_MEMCPY(a+a[0]+1, b+2, i * sizeof(ID));
1365                 a[0] += i;
1366         }
1367         if ( swap ) {
1368                 b[b[0]] = swap;
1369         }
1370         return 0;
1371 }
1372
1373 #if 1
1374
1375 /* Quicksort + Insertion sort for small arrays */
1376
1377 #define SMALL   8
1378 #define SWAP(a,b)       itmp=(a);(a)=(b);(b)=itmp
1379
1380 void
1381 bdb_idl_sort( ID *ids, ID *tmp )
1382 {
1383         int *istack = (int *)tmp;
1384         int i,j,k,l,ir,jstack;
1385         ID a, itmp;
1386
1387         if ( BDB_IDL_IS_RANGE( ids ))
1388                 return;
1389
1390         ir = ids[0];
1391         l = 1;
1392         jstack = 0;
1393         for(;;) {
1394                 if (ir - l < SMALL) {   /* Insertion sort */
1395                         for (j=l+1;j<=ir;j++) {
1396                                 a = ids[j];
1397                                 for (i=j-1;i>=1;i--) {
1398                                         if (ids[i] <= a) break;
1399                                         ids[i+1] = ids[i];
1400                                 }
1401                                 ids[i+1] = a;
1402                         }
1403                         if (jstack == 0) break;
1404                         ir = istack[jstack--];
1405                         l = istack[jstack--];
1406                 } else {
1407                         k = (l + ir) >> 1;      /* Choose median of left, center, right */
1408                         SWAP(ids[k], ids[l+1]);
1409                         if (ids[l] > ids[ir]) {
1410                                 SWAP(ids[l], ids[ir]);
1411                         }
1412                         if (ids[l+1] > ids[ir]) {
1413                                 SWAP(ids[l+1], ids[ir]);
1414                         }
1415                         if (ids[l] > ids[l+1]) {
1416                                 SWAP(ids[l], ids[l+1]);
1417                         }
1418                         i = l+1;
1419                         j = ir;
1420                         a = ids[l+1];
1421                         for(;;) {
1422                                 do i++; while(ids[i] < a);
1423                                 do j--; while(ids[j] > a);
1424                                 if (j < i) break;
1425                                 SWAP(ids[i],ids[j]);
1426                         }
1427                         ids[l+1] = ids[j];
1428                         ids[j] = a;
1429                         jstack += 2;
1430                         if (ir-i+1 >= j-1) {
1431                                 istack[jstack] = ir;
1432                                 istack[jstack-1] = i;
1433                                 ir = j-1;
1434                         } else {
1435                                 istack[jstack] = j-1;
1436                                 istack[jstack-1] = l;
1437                                 l = i;
1438                         }
1439                 }
1440         }
1441 }
1442
1443 #else
1444
1445 /* 8 bit Radix sort + insertion sort
1446  *
1447  * based on code from http://www.cubic.org/docs/radix.htm
1448  * with improvements by mbackes@symas.com and hyc@symas.com
1449  *
1450  * This code is O(n) but has a relatively high constant factor. For lists
1451  * up to ~50 Quicksort is slightly faster; up to ~100 they are even.
1452  * Much faster than quicksort for lists longer than ~100. Insertion
1453  * sort is actually superior for lists <50.
1454  */
1455
1456 #define BUCKETS (1<<8)
1457 #define SMALL   50
1458
1459 void
1460 bdb_idl_sort( ID *ids, ID *tmp )
1461 {
1462         int count, soft_limit, phase = 0, size = ids[0];
1463         ID *idls[2];
1464         unsigned char *maxv = (unsigned char *)&ids[size];
1465
1466         if ( BDB_IDL_IS_RANGE( ids ))
1467                 return;
1468
1469         /* Use insertion sort for small lists */
1470         if ( size <= SMALL ) {
1471                 int i,j;
1472                 ID a;
1473
1474                 for (j=1;j<=size;j++) {
1475                         a = ids[j];
1476                         for (i=j-1;i>=1;i--) {
1477                                 if (ids[i] <= a) break;
1478                                 ids[i+1] = ids[i];
1479                         }
1480                         ids[i+1] = a;
1481                 }
1482                 return;
1483         }
1484
1485         tmp[0] = size;
1486         idls[0] = ids;
1487         idls[1] = tmp;
1488
1489 #if BYTE_ORDER == BIG_ENDIAN
1490     for (soft_limit = 0; !maxv[soft_limit]; soft_limit++);
1491 #else
1492     for (soft_limit = sizeof(ID)-1; !maxv[soft_limit]; soft_limit--);
1493 #endif
1494
1495         for (
1496 #if BYTE_ORDER == BIG_ENDIAN
1497         count = sizeof(ID)-1; count >= soft_limit; --count
1498 #else
1499         count = 0; count <= soft_limit; ++count
1500 #endif
1501         ) {
1502                 unsigned int num[BUCKETS], * np, n, sum;
1503                 int i;
1504         ID *sp, *source, *dest;
1505         unsigned char *bp, *source_start;
1506
1507                 source = idls[phase]+1;
1508                 dest = idls[phase^1]+1;
1509                 source_start =  ((unsigned char *) source) + count;
1510
1511         np = num;
1512         for ( i = BUCKETS; i > 0; --i ) *np++ = 0;
1513
1514                 /* count occurences of every byte value */
1515                 bp = source_start;
1516         for ( i = size; i > 0; --i, bp += sizeof(ID) )
1517                                 num[*bp]++;
1518
1519                 /* transform count into index by summing elements and storing
1520                  * into same array
1521                  */
1522         sum = 0;
1523         np = num;
1524         for ( i = BUCKETS; i > 0; --i ) {
1525                 n = *np;
1526                 *np++ = sum;
1527                 sum += n;
1528         }
1529
1530                 /* fill dest with the right values in the right place */
1531                 bp = source_start;
1532         sp = source;
1533         for ( i = size; i > 0; --i, bp += sizeof(ID) ) {
1534                 np = num + *bp;
1535                 dest[*np] = *sp++;
1536                 ++(*np);
1537         }
1538                 phase ^= 1;
1539         }
1540
1541         /* copy back from temp if needed */
1542         if ( phase ) {
1543                 ids++; tmp++;
1544                 for ( count = 0; count < size; ++count )
1545                         *ids++ = *tmp++;
1546         }
1547 }
1548 #endif  /* Quick vs Radix */
1549
1550 #endif  /* BDB_HIER */