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[openldap] / servers / slapd / back-ldbm / idl.c
1 /* idl.c - ldap id list handling routines */
2
3 #include "portable.h"
4
5 #include <stdio.h>
6
7 #include <ac/string.h>
8 #include <ac/socket.h>
9
10 #include "ldapconfig.h"
11 #include "slap.h"
12 #include "back-ldbm.h"
13
14 static ID_BLOCK* idl_dup( ID_BLOCK *idl );
15
16 /* Allocate an ID_BLOCK with room for nids ids */
17 ID_BLOCK *
18 idl_alloc( int nids )
19 {
20         ID_BLOCK        *new;
21
22         /* nmax + nids + space for the ids */
23         new = (ID_BLOCK *) ch_calloc( (ID_BLOCK_IDS_OFFSET + nids), sizeof(ID) );
24         ID_BLOCK_NMAX(new) = nids;
25         ID_BLOCK_NIDS(new) = 0;
26
27         return( new );
28 }
29
30
31 /* Allocate an empty ALLIDS ID_BLOCK */
32 ID_BLOCK        *
33 idl_allids( Backend *be )
34 {
35         ID_BLOCK        *idl;
36
37         idl = idl_alloc( 0 );
38         ID_BLOCK_NMAX(idl) = ID_BLOCK_ALLIDS_VALUE;
39         ID_BLOCK_NIDS(idl) = next_id_get( be );
40
41         return( idl );
42 }
43
44
45 /* Free an ID_BLOCK */
46 void
47 idl_free( ID_BLOCK *idl )
48 {
49         if ( idl == NULL ) {
50                 Debug( LDAP_DEBUG_TRACE,
51                         "idl_free: called with NULL pointer\n",
52                         0, 0, 0 );
53                 return;
54         }
55
56         free( (char *) idl );
57 }
58
59
60 /* Fetch an single ID_BLOCK from the cache */
61 static ID_BLOCK *
62 idl_fetch_one(
63     Backend             *be,
64     struct dbcache      *db,
65     Datum               key
66 )
67 {
68         Datum   data;
69         ID_BLOCK        *idl;
70
71         ldbm_datum_init( data );
72
73         /* Debug( LDAP_DEBUG_TRACE, "=> idl_fetch_one\n", 0, 0, 0 ); */
74
75         data = ldbm_cache_fetch( db, key );
76
77         if( data.dptr == NULL ) {
78                 return NULL;
79         }
80
81         idl = idl_dup( (ID_BLOCK *) data.dptr);
82         ldbm_datum_free( db->dbc_db, data );
83
84         return( idl );
85 }
86
87
88 /* Fetch a set of ID_BLOCKs from the cache
89  *      if not INDIRECT
90  *              if block return is an ALLIDS block,
91  *                      return an new ALLIDS block
92  *              otherwise
93  *                      return block
94  *      construct super block from all blocks referenced by INDIRECT block
95  *      return super block
96  */
97 ID_BLOCK *
98 idl_fetch(
99     Backend             *be,
100     struct dbcache      *db,
101     Datum               key
102 )
103 {
104         Datum   data;
105         ID_BLOCK        *idl;
106         ID_BLOCK        **tmp;
107         char    *kstr;
108         int     i, nids;
109
110         ldbm_datum_init( data );
111
112         /* Debug( LDAP_DEBUG_TRACE, "=> idl_fetch\n", 0, 0, 0 ); */
113
114         data = ldbm_cache_fetch( db, key );
115
116         if ( data.dptr == NULL ) {
117                 return( NULL );
118         }
119
120         idl = idl_dup( (ID_BLOCK *) data.dptr );
121         ldbm_datum_free( db->dbc_db, data);
122
123         if ( ID_BLOCK_ALLIDS(idl) ) {
124                 /* all ids block */
125                 /* make sure we have the current value of highest id */
126                 idl_free( idl );
127                 idl = idl_allids( be );
128
129                 return idl;
130         }
131
132         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
133                 /* regular block */
134                 return( idl );
135         }
136
137         /*
138          * this is an indirect block which points to other blocks.
139          * we need to read in all the blocks it points to and construct
140          * a big id list containing all the ids, which we will return.
141          */
142
143         /* count the number of blocks & allocate space for pointers to them */
144         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ )
145                 ;       /* NULL */
146         tmp = (ID_BLOCK **) ch_malloc( (i + 1) * sizeof(ID_BLOCK *) );
147
148         /* read in all the blocks */
149         kstr = (char *) ch_malloc( key.dsize + 20 );
150         nids = 0;
151         for ( i = 0; !ID_BLOCK_NOID(idl, i); i++ ) {
152                 ldbm_datum_init( data );
153
154                 sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr, ID_BLOCK_ID(idl, i) );
155                 data.dptr = kstr;
156                 data.dsize = strlen( kstr ) + 1;
157
158                 if ( (tmp[i] = idl_fetch_one( be, db, data )) == NULL ) {
159                         Debug( LDAP_DEBUG_ANY,
160                             "idl_fetch of (%s) returns NULL\n", data.dptr, 0, 0 );
161                         continue;
162                 }
163
164                 nids += ID_BLOCK_NIDS(tmp[i]);
165         }
166         tmp[i] = NULL;
167         free( kstr );
168         idl_free( idl );
169
170         /* allocate space for the big block */
171         idl = idl_alloc( nids );
172         ID_BLOCK_NIDS(idl) = nids;
173         nids = 0;
174
175         /* copy in all the ids from the component blocks */
176         for ( i = 0; tmp[i] != NULL; i++ ) {
177                 if ( tmp[i] == NULL ) {
178                         continue;
179                 }
180
181                 SAFEMEMCPY(
182                         (char *) &ID_BLOCK_ID(idl, nids),
183                         (char *) &ID_BLOCK_ID(tmp[i], 0),
184                         ID_BLOCK_NIDS(tmp[i]) * sizeof(ID) );
185                 nids += ID_BLOCK_NIDS(tmp[i]);
186
187                 idl_free( tmp[i] );
188         }
189         free( (char *) tmp );
190
191         Debug( LDAP_DEBUG_TRACE, "<= idl_fetch %lu ids (%lu max)\n",
192                ID_BLOCK_NIDS(idl), ID_BLOCK_NMAX(idl), 0 );
193         return( idl );
194 }
195
196
197 /* store a single block */
198 static int
199 idl_store(
200     Backend             *be,
201     struct dbcache      *db,
202     Datum               key, 
203     ID_BLOCK            *idl
204 )
205 {
206         int     rc, flags;
207         Datum   data;
208         struct ldbminfo *li = (struct ldbminfo *) be->be_private;
209
210         ldbm_datum_init( data );
211
212         /* Debug( LDAP_DEBUG_TRACE, "=> idl_store\n", 0, 0, 0 ); */
213
214         data.dptr = (char *) idl;
215         data.dsize = (ID_BLOCK_IDS_OFFSET + ID_BLOCK_NMAX(idl)) * sizeof(ID);
216         
217 #ifdef LDBM_DEBUG
218         Statslog( LDAP_DEBUG_STATS, "<= idl_store(): rc=%d\n",
219                 rc, 0, 0, 0, 0 );
220 #endif
221
222         flags = LDBM_REPLACE;
223         if( li->li_dbcachewsync ) flags |= LDBM_SYNC;
224         rc = ldbm_cache_store( db, key, data, flags );
225
226         /* Debug( LDAP_DEBUG_TRACE, "<= idl_store %d\n", rc, 0, 0 ); */
227         return( rc );
228 }
229
230
231 /* split the block at id 
232  *      locate ID greater than or equal to id.
233  */
234 static void
235 idl_split_block(
236     ID_BLOCK    *b,
237     ID          id,
238     ID_BLOCK    **right,
239     ID_BLOCK    **left
240 )
241 {
242         unsigned int    nr, nl;
243
244         /* find where to split the block *//* XXX linear search XXX */
245         for ( nr = 0; nr < ID_BLOCK_NIDS(b) && id > ID_BLOCK_ID(b, nr); nr++ )
246                 ;       /* NULL */
247
248         nl = ID_BLOCK_NIDS(b) - nr;
249
250         *right = idl_alloc( nr == 0 ? 1 : nr );
251         *left = idl_alloc( nl + (nr == 0 ? 0 : 1));
252
253         /*
254          * everything before the id being inserted in the first block
255          * unless there is nothing, in which case the id being inserted
256          * goes there.
257          */
258         if ( nr == 0 ) {
259                 ID_BLOCK_NIDS(*right) = 1;
260                 ID_BLOCK_ID(*right, 0) = id;
261         } else {
262                 SAFEMEMCPY(
263                         (char *) &ID_BLOCK_ID(*right, 0),
264                         (char *) &ID_BLOCK_ID(b, 0),
265                         nr * sizeof(ID) );
266                 ID_BLOCK_NIDS(*right) = nr;
267                 ID_BLOCK_ID(*left, 0) = id;
268         }
269
270         /* the id being inserted & everything after in the second block */
271         SAFEMEMCPY(
272                 (char *) &ID_BLOCK_ID(*left, (nr == 0 ? 0 : 1)),
273             (char *) &ID_BLOCK_ID(b, nr),
274                 nl * sizeof(ID) );
275         ID_BLOCK_NIDS(*left) = nl + (nr == 0 ? 0 : 1);
276 }
277
278
279 /*
280  * idl_change_first - called when an indirect block's first key has
281  * changed, meaning it needs to be stored under a new key, and the
282  * header block pointing to it needs updating.
283  */
284 static int
285 idl_change_first(
286     Backend             *be,
287     struct dbcache      *db,
288     Datum               hkey,           /* header block key     */
289     ID_BLOCK            *h,             /* header block         */
290     int                 pos,            /* pos in h to update   */
291     Datum               bkey,           /* data block key       */
292     ID_BLOCK            *b              /* data block           */
293 )
294 {
295         int     rc;
296
297         /* Debug( LDAP_DEBUG_TRACE, "=> idl_change_first\n", 0, 0, 0 ); */
298
299         /* delete old key block */
300         if ( (rc = ldbm_cache_delete( db, bkey )) != 0 ) {
301                 Debug( LDAP_DEBUG_ANY,
302                     "ldbm_delete of (%s) returns %d\n", bkey.dptr, rc,
303                     0 );
304                 return( rc );
305         }
306
307         /* write block with new key */
308         sprintf( bkey.dptr, "%c%s%ld", CONT_PREFIX, hkey.dptr, ID_BLOCK_ID(b, 0) );
309         bkey.dsize = strlen( bkey.dptr ) + 1;
310         if ( (rc = idl_store( be, db, bkey, b )) != 0 ) {
311                 Debug( LDAP_DEBUG_ANY,
312                     "idl_store of (%s) returns %d\n", bkey.dptr, rc, 0 );
313                 return( rc );
314         }
315
316         /* update + write indirect header block */
317         ID_BLOCK_ID(h, pos) = ID_BLOCK_ID(b, 0);
318         if ( (rc = idl_store( be, db, hkey, h )) != 0 ) {
319                 Debug( LDAP_DEBUG_ANY,
320                     "idl_store of (%s) returns %d\n", hkey.dptr, rc, 0 );
321                 return( rc );
322         }
323
324         return( 0 );
325 }
326
327
328 int
329 idl_insert_key(
330     Backend             *be,
331     struct dbcache      *db,
332     Datum               key,
333     ID                  id
334 )
335 {
336         int     i, j, first, rc;
337         ID_BLOCK        *idl, *tmp, *tmp2, *tmp3;
338         char    *kstr;
339         Datum   k2;
340
341         ldbm_datum_init( k2 );
342
343         if ( (idl = idl_fetch_one( be, db, key )) == NULL ) {
344 #ifdef LDBM_DEBUG
345                 Statslog( LDAP_DEBUG_STATS, "=> idl_insert_key(): no key yet\n",
346                         0, 0, 0, 0, 0 );
347 #endif
348
349                 idl = idl_alloc( 1 );
350                 ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)++) = id;
351                 rc = idl_store( be, db, key, idl );
352
353                 idl_free( idl );
354                 return( rc );
355         }
356
357         if ( ID_BLOCK_ALLIDS( idl ) ) {
358                 /* ALLIDS */
359                 idl_free( idl );
360                 return 0;
361         }
362
363         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
364                 /* regular block */
365                 switch ( idl_insert( &idl, id, db->dbc_maxids ) ) {
366                 case 0:         /* id inserted - store the updated block */
367                 case 1:
368                         rc = idl_store( be, db, key, idl );
369                         break;
370
371                 case 2:         /* id already there - nothing to do */
372                         rc = 0;
373                         break;
374
375                 case 3:         /* id not inserted - block must be split */
376                         /* check threshold for marking this an all-id block */
377                         if ( db->dbc_maxindirect < 2 ) {
378                                 idl_free( idl );
379                                 idl = idl_allids( be );
380                                 rc = idl_store( be, db, key, idl );
381                                 idl_free( idl );
382
383                                 return( rc );
384                         }
385
386                         idl_split_block( idl, id, &tmp, &tmp2 );
387                         idl_free( idl );
388
389                         /* create the header indirect block */
390                         idl = idl_alloc( 3 );
391                         ID_BLOCK_NMAX(idl) = 3;
392                         ID_BLOCK_NIDS(idl) = ID_BLOCK_INDIRECT_VALUE;
393                         ID_BLOCK_ID(idl, 0) = ID_BLOCK_ID(tmp, 0);
394                         ID_BLOCK_ID(idl, 1) = ID_BLOCK_ID(tmp2, 0);
395                         ID_BLOCK_ID(idl, 2) = NOID;
396
397                         /* store it */
398                         rc = idl_store( be, db, key, idl );
399
400                         /* store the first id block */
401                         kstr = (char *) ch_malloc( key.dsize + 20 );
402                         sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
403                             ID_BLOCK_ID(tmp, 0) );
404                         k2.dptr = kstr;
405                         k2.dsize = strlen( kstr ) + 1;
406                         rc = idl_store( be, db, k2, tmp );
407
408                         /* store the second id block */
409                         sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
410                             ID_BLOCK_ID(tmp2, 0) );
411                         k2.dptr = kstr;
412                         k2.dsize = strlen( kstr ) + 1;
413                         rc = idl_store( be, db, k2, tmp2 );
414
415                         free( kstr );
416                         idl_free( tmp );
417                         idl_free( tmp2 );
418                         break;
419                 }
420
421                 idl_free( idl );
422                 return( rc );
423         }
424
425         /*
426          * this is an indirect block which points to other blocks.
427          * we need to read in the block into which the id should be
428          * inserted, then insert the id and store the block.  we might
429          * have to split the block if it is full, which means we also
430          * need to write a new "header" block.
431          */
432
433         /* select the block to try inserting into *//* XXX linear search XXX */
434         for ( i = 0; !ID_BLOCK_NOID(idl, i) && id > ID_BLOCK_ID(idl, i); i++ )
435                 ;       /* NULL */
436         if ( i != 0 ) {
437                 i--;
438                 first = 0;
439         } else {
440                 first = 1;
441         }
442
443         /* get the block */
444         kstr = (char *) ch_malloc( key.dsize + 20 );
445         sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr, ID_BLOCK_ID(idl, i) );
446         k2.dptr = kstr;
447         k2.dsize = strlen( kstr ) + 1;
448         if ( (tmp = idl_fetch_one( be, db, k2 )) == NULL ) {
449                 Debug( LDAP_DEBUG_ANY, "nonexistent continuation block (%s)\n",
450                     k2.dptr, 0, 0 );
451                 free( kstr );
452                 return( -1 );
453         }
454
455         /* insert the id */
456         switch ( idl_insert( &tmp, id, db->dbc_maxids ) ) {
457         case 0:         /* id inserted ok */
458                 if ( (rc = idl_store( be, db, k2, tmp )) != 0 ) {
459                         Debug( LDAP_DEBUG_ANY,
460                             "idl_store of (%s) returns %d\n", k2.dptr, rc, 0 );
461                 }
462                 break;
463
464         case 1:         /* id inserted - first id in block has changed */
465                 /*
466                  * key for this block has changed, so we have to
467                  * write the block under the new key, delete the
468                  * old key block + update and write the indirect
469                  * header block.
470                  */
471
472                 rc = idl_change_first( be, db, key, idl, i, k2, tmp );
473                 break;
474
475         case 2:         /* id not inserted - already there */
476                 break;
477
478         case 3:         /* id not inserted - block is full */
479                 /*
480                  * first, see if it will fit in the next block,
481                  * without splitting, unless we're trying to insert
482                  * into the beginning of the first block.
483                  */
484
485                 /* is there a next block? */
486                 if ( !first && !ID_BLOCK_NOID(idl, i + 1) ) {
487                         /* read it in */
488                         sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
489                             ID_BLOCK_ID(idl, i + 1) );
490                         k2.dptr = kstr;
491                         k2.dsize = strlen( kstr ) + 1;
492                         if ( (tmp2 = idl_fetch_one( be, db, k2 )) == NULL ) {
493                                 Debug( LDAP_DEBUG_ANY,
494                                     "idl_fetch_one (%s) returns NULL\n",
495                                     k2.dptr, 0, 0 );
496                                 break;
497                         }
498
499                         switch ( (rc = idl_insert( &tmp2, id,
500                             db->dbc_maxids )) ) {
501                         case 1:         /* id inserted first in block */
502                                 rc = idl_change_first( be, db, key, idl,
503                                     i + 1, k2, tmp2 );
504                                 /* FALL */
505
506                         case 2:         /* id already there - how? */
507                         case 0:         /* id inserted */
508                                 if ( rc == 2 ) {
509                                         Debug( LDAP_DEBUG_ANY,
510                                             "id %lu already in next block\n",
511                                             id, 0, 0 );
512                                 }
513                                 free( kstr );
514                                 idl_free( tmp );
515                                 idl_free( tmp2 );
516                                 idl_free( idl );
517                                 return( 0 );
518
519                         case 3:         /* split the original block */
520                                 idl_free( tmp2 );
521                                 break;
522                         }
523
524                 }
525
526                 /*
527                  * must split the block, write both new blocks + update
528                  * and write the indirect header block.
529                  */
530
531                 /* count how many indirect blocks *//* XXX linear count XXX */
532                 for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ )
533                         ;       /* NULL */
534
535                 /* check it against all-id thresholed */
536                 if ( j + 1 > db->dbc_maxindirect ) {
537                         /*
538                          * we've passed the all-id threshold, meaning
539                          * that this set of blocks should be replaced
540                          * by a single "all-id" block.  our job: delete
541                          * all the indirect blocks, and replace the header
542                          * block by an all-id block.
543                          */
544
545                         /* delete all indirect blocks */
546                         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ ) {
547                                 sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
548                                     ID_BLOCK_ID(idl, j) );
549                                 k2.dptr = kstr;
550                                 k2.dsize = strlen( kstr ) + 1;
551
552                                 rc = ldbm_cache_delete( db, k2 );
553                         }
554
555                         /* store allid block in place of header block */
556                         idl_free( idl );
557                         idl = idl_allids( be );
558                         rc = idl_store( be, db, key, idl );
559
560                         free( kstr );
561                         idl_free( idl );
562                         idl_free( tmp );
563                         return( rc );
564                 }
565
566                 idl_split_block( tmp, id, &tmp2, &tmp3 );
567                 idl_free( tmp );
568
569                 /* create a new updated indirect header block */
570                 tmp = idl_alloc( ID_BLOCK_NMAX(idl) + 1 );
571                 ID_BLOCK_NIDS(tmp) = ID_BLOCK_INDIRECT_VALUE;
572                 /* everything up to the split block */
573                 SAFEMEMCPY(
574                         (char *) &ID_BLOCK_ID(tmp, 0),
575                         (char *) &ID_BLOCK_ID(idl, 0),
576                     i * sizeof(ID) );
577                 /* the two new blocks */
578                 ID_BLOCK_ID(tmp, i) = ID_BLOCK_ID(tmp2, 0);
579                 ID_BLOCK_ID(tmp, i + 1) = ID_BLOCK_ID(tmp3, 0);
580                 /* everything after the split block */
581                 SAFEMEMCPY(
582                         (char *) &ID_BLOCK_ID(tmp, i + 2),
583                         (char *) &ID_BLOCK_ID(idl, i + 1),
584                         (ID_BLOCK_NMAX(idl) - i - 1) * sizeof(ID) );
585
586                 /* store the header block */
587                 rc = idl_store( be, db, key, tmp );
588
589                 /* store the first id block */
590                 sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
591                     ID_BLOCK_ID(tmp2, 0) );
592                 k2.dptr = kstr;
593                 k2.dsize = strlen( kstr ) + 1;
594                 rc = idl_store( be, db, k2, tmp2 );
595
596                 /* store the second id block */
597                 sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr,
598                     ID_BLOCK_ID(tmp3, 0) );
599                 k2.dptr = kstr;
600                 k2.dsize = strlen( kstr ) + 1;
601                 rc = idl_store( be, db, k2, tmp3 );
602
603                 idl_free( tmp2 );
604                 idl_free( tmp3 );
605                 break;
606         }
607
608         free( kstr );
609         idl_free( tmp );
610         idl_free( idl );
611         return( rc );
612 }
613
614
615 /*
616  * idl_insert - insert an id into an id list.
617  *
618  *      returns
619  *              0       id inserted
620  *              1       id inserted, first id in block has changed
621  *              2       id not inserted, already there
622  *              3       id not inserted, block must be split
623  */
624 int
625 idl_insert( ID_BLOCK **idl, ID id, int maxids )
626 {
627         unsigned int    i, j;
628
629         if ( ID_BLOCK_ALLIDS( *idl ) ) {
630                 return( 2 );    /* already there */
631         }
632
633         /* is it already there? *//* XXX linear search XXX */
634         for ( i = 0; i < ID_BLOCK_NIDS(*idl) && id > ID_BLOCK_ID(*idl, i); i++ ) {
635                 ;       /* NULL */
636         }
637         if ( i < ID_BLOCK_NIDS(*idl) && ID_BLOCK_ID(*idl, i) == id ) {
638                 return( 2 );    /* already there */
639         }
640
641         /* do we need to make room for it? */
642         if ( ID_BLOCK_NIDS(*idl) == ID_BLOCK_NMAX(*idl) ) {
643                 /* make room or indicate block needs splitting */
644                 if ( ID_BLOCK_NMAX(*idl) >= maxids ) {
645                         return( 3 );    /* block needs splitting */
646                 }
647
648                 ID_BLOCK_NMAX(*idl) *= 2;
649                 if ( ID_BLOCK_NMAX(*idl) > maxids ) {
650                         ID_BLOCK_NMAX(*idl) = maxids;
651                 }
652                 *idl = (ID_BLOCK *) ch_realloc( (char *) *idl,
653                     (ID_BLOCK_NMAX(*idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
654         }
655
656         /* make a slot for the new id *//* XXX bubble move XXX */
657         for ( j = ID_BLOCK_NIDS(*idl); j != i; j-- ) {
658                 ID_BLOCK_ID(*idl, j) = ID_BLOCK_ID(*idl, j-1);
659         }
660         ID_BLOCK_ID(*idl, i) = id;
661         ID_BLOCK_NIDS(*idl)++;
662         (void) memset(
663                 (char *) &ID_BLOCK_ID((*idl), ID_BLOCK_NIDS(*idl)),
664                 '\0',
665             (ID_BLOCK_NMAX(*idl) - ID_BLOCK_NIDS(*idl)) * sizeof(ID) );
666
667         return( i == 0 ? 1 : 0 );       /* inserted - first id changed or not */
668 }
669
670
671 int
672 idl_delete_key (
673         Backend         *be,
674         struct dbcache  *db,
675         Datum           key,
676         ID              id
677 )
678 {
679         Datum  data;
680         ID_BLOCK *idl, *tmp;
681         unsigned i;
682         int j, nids;
683         char    *kstr;
684
685         if ( (idl = idl_fetch_one( be, db, key ) ) == NULL )
686         {
687                 /* It wasn't found.  Hmm... */
688                 return -1;
689         }
690
691         if ( ID_BLOCK_ALLIDS( idl ) ) {
692                 idl_free( idl );
693                 return 0;
694         }
695
696         if ( ! ID_BLOCK_INDIRECT( idl ) ) {
697                 for ( i=0; i < ID_BLOCK_NIDS(idl); i++ ) {
698                         if ( ID_BLOCK_ID(idl, i) == id ) {
699                                 if( --ID_BLOCK_NIDS(idl) == 0 ) {
700                                         ldbm_cache_delete( db, key );
701
702                                 } else {
703                                         SAFEMEMCPY (
704                                                 &ID_BLOCK_ID(idl, i),
705                                                 &ID_BLOCK_ID(idl, i+1),
706                                                 (ID_BLOCK_NIDS(idl)-i) * sizeof(ID) );
707
708                                         ID_BLOCK_ID(idl, ID_BLOCK_NIDS(idl)) = NOID;
709
710                                         idl_store( be, db, key, idl );
711                                 }
712
713                                 return 0;
714                         }
715                         /*  We didn't find the ID.  Hmmm... */
716                 }
717                 return -1;
718         }
719         
720         /* We have to go through an indirect block and find the ID
721            in the list of IDL's
722            */
723         for ( nids = 0; !ID_BLOCK_NOID(idl, nids); nids++ )
724                 ;       /* NULL */
725         kstr = (char *) ch_malloc( key.dsize + 20 );
726
727         for ( j = 0; !ID_BLOCK_NOID(idl, j); j++ ) 
728         {
729                 ldbm_datum_init( data );
730                 sprintf( kstr, "%c%s%ld", CONT_PREFIX, key.dptr, ID_BLOCK_ID(idl, j) );
731                 data.dptr = kstr;
732                 data.dsize = strlen( kstr ) + 1;
733
734                 if ( (tmp = idl_fetch_one( be, db, data )) == NULL ) {
735                         Debug( LDAP_DEBUG_ANY,
736                             "idl_fetch of (%s) returns NULL\n", data.dptr, 0, 0 );
737                         continue;
738                 }
739                 /*
740                    Now try to find the ID in tmp
741                 */
742                 for ( i=0; i < ID_BLOCK_NIDS(tmp); i++ )
743                 {
744                         if ( ID_BLOCK_ID(tmp, i) == id )
745                         {
746                                 SAFEMEMCPY(
747                                         &ID_BLOCK_ID(tmp, i),
748                                         &ID_BLOCK_ID(tmp, i+1),
749                                         (ID_BLOCK_NIDS(tmp)-(i+1)) * sizeof(ID));
750                                 ID_BLOCK_ID(tmp, ID_BLOCK_NIDS(tmp)-1 ) = NOID;
751                                 ID_BLOCK_NIDS(tmp)--;
752
753                                 if ( ID_BLOCK_NIDS(tmp) ) {
754                                         idl_store ( be, db, data, tmp );
755
756                                 } else {
757                                         ldbm_cache_delete( db, data );
758                                         SAFEMEMCPY(
759                                                 &ID_BLOCK_ID(idl, j),
760                                                 &ID_BLOCK_ID(idl, j+1),
761                                                 (nids-(j+1)) * sizeof(ID));
762                                         ID_BLOCK_ID(idl, nids-1) = NOID;
763                                         nids--;
764                                         if ( ! nids )
765                                                 ldbm_cache_delete( db, key );
766                                         else
767                                                 idl_store( be, db, key, idl );
768                                 }
769                                 free( kstr );
770                                 return 0;
771                         }
772                 }
773         }
774         free( kstr );
775         return -1;
776 }
777
778
779 /* return a duplicate of a single ID_BLOCK */
780 static ID_BLOCK *
781 idl_dup( ID_BLOCK *idl )
782 {
783         ID_BLOCK        *new;
784
785         if ( idl == NULL ) {
786                 return( NULL );
787         }
788
789         new = idl_alloc( ID_BLOCK_NMAX(idl) );
790
791         SAFEMEMCPY(
792                 (char *) new,
793                 (char *) idl,
794                 (ID_BLOCK_NMAX(idl) + ID_BLOCK_IDS_OFFSET) * sizeof(ID) );
795
796         return( new );
797 }
798
799
800 /* return the smaller ID_BLOCK */
801 static ID_BLOCK *
802 idl_min( ID_BLOCK *a, ID_BLOCK *b )
803 {
804         return( ID_BLOCK_NIDS(a) > ID_BLOCK_NIDS(b) ? b : a );
805 }
806
807
808 /*
809  * idl_intersection - return a intersection b
810  */
811 ID_BLOCK *
812 idl_intersection(
813     Backend     *be,
814     ID_BLOCK    *a,
815     ID_BLOCK    *b
816 )
817 {
818         unsigned int    ai, bi, ni;
819         ID_BLOCK                *n;
820
821         if ( a == NULL || b == NULL ) {
822                 return( NULL );
823         }
824         if ( ID_BLOCK_ALLIDS( a ) ) {
825                 return( idl_dup( b ) );
826         }
827         if ( ID_BLOCK_ALLIDS( b ) ) {
828                 return( idl_dup( a ) );
829         }
830
831         n = idl_dup( idl_min( a, b ) );
832
833         for ( ni = 0, ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
834                 for ( ;
835                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
836                         bi++ )
837                 {
838                         ;       /* NULL */
839                 }
840
841                 if ( bi == ID_BLOCK_NIDS(b) ) {
842                         break;
843                 }
844
845                 if ( ID_BLOCK_ID(b, bi) == ID_BLOCK_ID(a, ai) ) {
846                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
847                 }
848         }
849
850         if ( ni == 0 ) {
851                 idl_free( n );
852                 return( NULL );
853         }
854         ID_BLOCK_NIDS(n) = ni;
855
856         return( n );
857 }
858
859
860 /*
861  * idl_union - return a union b
862  */
863 ID_BLOCK *
864 idl_union(
865     Backend     *be,
866     ID_BLOCK    *a,
867     ID_BLOCK    *b
868 )
869 {
870         unsigned int    ai, bi, ni;
871         ID_BLOCK                *n;
872
873         if ( a == NULL ) {
874                 return( idl_dup( b ) );
875         }
876         if ( b == NULL ) {
877                 return( idl_dup( a ) );
878         }
879         if ( ID_BLOCK_ALLIDS( a ) || ID_BLOCK_ALLIDS( b ) ) {
880                 return( idl_allids( be ) );
881         }
882
883         if ( ID_BLOCK_NIDS(b) < ID_BLOCK_NIDS(a) ) {
884                 n = a;
885                 a = b;
886                 b = n;
887         }
888
889         n = idl_alloc( ID_BLOCK_NIDS(a) + ID_BLOCK_NIDS(b) );
890
891         for ( ni = 0, ai = 0, bi = 0;
892                 ai < ID_BLOCK_NIDS(a) && bi < ID_BLOCK_NIDS(b);
893                 )
894         {
895                 if ( ID_BLOCK_ID(a, ai) < ID_BLOCK_ID(b, bi) ) {
896                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai++);
897
898                 } else if ( ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai) ) {
899                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi++);
900
901                 } else {
902                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
903                         ai++, bi++;
904                 }
905         }
906
907         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
908                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
909         }
910         for ( ; bi < ID_BLOCK_NIDS(b); bi++ ) {
911                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(b, bi);
912         }
913         ID_BLOCK_NIDS(n) = ni;
914
915         return( n );
916 }
917
918
919 /*
920  * idl_notin - return a intersection ~b (or a minus b)
921  */
922 ID_BLOCK *
923 idl_notin(
924     Backend     *be,
925     ID_BLOCK    *a,
926     ID_BLOCK    *b
927 )
928 {
929         unsigned int    ni, ai, bi;
930         ID_BLOCK                *n;
931
932         if ( a == NULL ) {
933                 return( NULL );
934         }
935         if ( b == NULL || ID_BLOCK_ALLIDS( b )) {
936                 return( idl_dup( a ) );
937         }
938
939         if ( ID_BLOCK_ALLIDS( a ) ) {
940                 n = idl_alloc( SLAPD_LDBM_MIN_MAXIDS );
941                 ni = 0;
942
943                 for ( ai = 1, bi = 0;
944                         ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n) && bi < ID_BLOCK_NMAX(b);
945                         ai++ )
946                 {
947                         if ( ID_BLOCK_ID(b, bi) == ai ) {
948                                 bi++;
949                         } else {
950                                 ID_BLOCK_ID(n, ni++) = ai;
951                         }
952                 }
953
954                 for ( ; ai < ID_BLOCK_NIDS(a) && ni < ID_BLOCK_NMAX(n); ai++ ) {
955                         ID_BLOCK_ID(n, ni++) = ai;
956                 }
957
958                 if ( ni == ID_BLOCK_NMAX(n) ) {
959                         idl_free( n );
960                         return( idl_allids( be ) );
961                 } else {
962                         ID_BLOCK_NIDS(n) = ni;
963                         return( n );
964                 }
965         }
966
967         n = idl_dup( a );
968
969         ni = 0;
970         for ( ai = 0, bi = 0; ai < ID_BLOCK_NIDS(a); ai++ ) {
971                 for ( ;
972                         bi < ID_BLOCK_NIDS(b) && ID_BLOCK_ID(b, bi) < ID_BLOCK_ID(a, ai);
973                     bi++ )
974                 {
975                         ;       /* NULL */
976                 }
977
978                 if ( bi == ID_BLOCK_NIDS(b) ) {
979                         break;
980                 }
981
982                 if ( ID_BLOCK_ID(b, bi) != ID_BLOCK_ID(a, ai) ) {
983                         ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
984                 }
985         }
986
987         for ( ; ai < ID_BLOCK_NIDS(a); ai++ ) {
988                 ID_BLOCK_ID(n, ni++) = ID_BLOCK_ID(a, ai);
989         }
990         ID_BLOCK_NIDS(n) = ni;
991
992         return( n );
993 }
994
995 /*      return the first ID in the block
996  *      if ALLIDS block
997  *              NIDS > 1 return 1
998  *              otherwise return NOID 
999  *      otherwise return first ID
1000  */         
1001 ID
1002 idl_firstid( ID_BLOCK *idl )
1003 {
1004         if ( idl == NULL || ID_BLOCK_NIDS(idl) == 0 ) {
1005                 return( NOID );
1006         }
1007
1008         if ( ID_BLOCK_ALLIDS( idl ) ) {
1009                 return( ID_BLOCK_NIDS(idl) > 1 ? 1 : NOID );
1010         }
1011
1012         return( ID_BLOCK_ID(idl, 0) );
1013 }
1014
1015 /*      return next ID after id
1016  *      if ALLIDS block, increment id. 
1017  *              if id < NIDS return id
1018  *              otherwise NOID.
1019  *      otherwise SEARCH for next id (ugh!)
1020  */ 
1021 ID
1022 idl_nextid( ID_BLOCK *idl, ID id )
1023 {
1024         unsigned int    i;
1025
1026         if ( ID_BLOCK_ALLIDS( idl ) ) {
1027                 return( ++id < ID_BLOCK_NIDS(idl) ? id : NOID );
1028         }
1029
1030         for ( i = 0; i < ID_BLOCK_NIDS(idl) && ID_BLOCK_ID(idl, i) <= id; i++ ) {
1031                 ;       /* NULL */
1032         }
1033
1034         if ( i >= ID_BLOCK_NIDS(idl) ) {
1035                 return( NOID );
1036         } else {
1037                 return( ID_BLOCK_ID(idl, i) );
1038         }
1039 }