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