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      1 /*	$NetBSD: attr.c,v 1.4 2025/09/05 21:16:24 christos Exp $	*/
      2 
      3 /* attr.c - routines for dealing with attributes */
      4 /* $OpenLDAP$ */
      5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
      6  *
      7  * Copyright 1998-2024 The OpenLDAP Foundation.
      8  * All rights reserved.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted only as authorized by the OpenLDAP
     12  * Public License.
     13  *
     14  * A copy of this license is available in the file LICENSE in the
     15  * top-level directory of the distribution or, alternatively, at
     16  * <http://www.OpenLDAP.org/license.html>.
     17  */
     18 /* Portions Copyright (c) 1995 Regents of the University of Michigan.
     19  * All rights reserved.
     20  *
     21  * Redistribution and use in source and binary forms are permitted
     22  * provided that this notice is preserved and that due credit is given
     23  * to the University of Michigan at Ann Arbor. The name of the University
     24  * may not be used to endorse or promote products derived from this
     25  * software without specific prior written permission. This software
     26  * is provided ``as is'' without express or implied warranty.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 __RCSID("$NetBSD: attr.c,v 1.4 2025/09/05 21:16:24 christos Exp $");
     31 
     32 #include "portable.h"
     33 
     34 #include <stdio.h>
     35 
     36 #ifdef HAVE_FCNTL_H
     37 #include <fcntl.h>
     38 #endif
     39 
     40 #include <ac/ctype.h>
     41 #include <ac/errno.h>
     42 #include <ac/socket.h>
     43 #include <ac/string.h>
     44 #include <ac/time.h>
     45 
     46 #include "slap.h"
     47 
     48 /*
     49  * Allocate in chunks, minimum of 1000 at a time.
     50  */
     51 #define	CHUNK_SIZE	1000
     52 typedef struct slap_list {
     53 	struct slap_list *next;
     54 } slap_list;
     55 static slap_list *attr_chunks;
     56 static Attribute *attrs_list;
     57 static ldap_pvt_thread_mutex_t attr_mutex;
     58 
     59 int
     60 attr_prealloc( int num )
     61 {
     62 	Attribute *a;
     63 	slap_list *s;
     64 
     65 	if (!num) return 0;
     66 
     67 	s = ch_calloc( 1, sizeof(slap_list) + num * sizeof(Attribute));
     68 	s->next = attr_chunks;
     69 	attr_chunks = s;
     70 
     71 	a = (Attribute *)(s+1);
     72 	for ( ;num>1; num--) {
     73 		a->a_next = a+1;
     74 		a++;
     75 	}
     76 	a->a_next = attrs_list;
     77 	attrs_list = (Attribute *)(s+1);
     78 
     79 	return 0;
     80 }
     81 
     82 Attribute *
     83 attr_alloc( AttributeDescription *ad )
     84 {
     85 	Attribute *a;
     86 
     87 	ldap_pvt_thread_mutex_lock( &attr_mutex );
     88 	if ( !attrs_list )
     89 		attr_prealloc( CHUNK_SIZE );
     90 	a = attrs_list;
     91 	attrs_list = a->a_next;
     92 	a->a_next = NULL;
     93 	ldap_pvt_thread_mutex_unlock( &attr_mutex );
     94 
     95 	a->a_desc = ad;
     96 	if ( ad && ( ad->ad_type->sat_flags & SLAP_AT_SORTED_VAL ))
     97 		a->a_flags |= SLAP_ATTR_SORTED_VALS;
     98 
     99 	return a;
    100 }
    101 
    102 /* Return a list of num attrs */
    103 Attribute *
    104 attrs_alloc( int num )
    105 {
    106 	Attribute *head = NULL;
    107 	Attribute **a;
    108 
    109 	ldap_pvt_thread_mutex_lock( &attr_mutex );
    110 	for ( a = &attrs_list; *a && num > 0; a = &(*a)->a_next ) {
    111 		if ( !head )
    112 			head = *a;
    113 		num--;
    114 	}
    115 	attrs_list = *a;
    116 	if ( num > 0 ) {
    117 		attr_prealloc( num > CHUNK_SIZE ? num : CHUNK_SIZE );
    118 		*a = attrs_list;
    119 		for ( ; *a && num > 0; a = &(*a)->a_next ) {
    120 			if ( !head )
    121 				head = *a;
    122 			num--;
    123 		}
    124 		attrs_list = *a;
    125 	}
    126 	*a = NULL;
    127 	ldap_pvt_thread_mutex_unlock( &attr_mutex );
    128 
    129 	return head;
    130 }
    131 
    132 
    133 void
    134 attr_clean( Attribute *a )
    135 {
    136 	if ( a->a_nvals && a->a_nvals != a->a_vals &&
    137 		!( a->a_flags & SLAP_ATTR_DONT_FREE_VALS )) {
    138 		if ( a->a_flags & SLAP_ATTR_DONT_FREE_DATA ) {
    139 			free( a->a_nvals );
    140 		} else {
    141 			ber_bvarray_free( a->a_nvals );
    142 		}
    143 	}
    144 	/* a_vals may be equal to slap_dummy_bv, a static empty berval;
    145 	 * this is used as a placeholder for attributes that do not carry
    146 	 * values, e.g. when proxying search entries with the "attrsonly"
    147 	 * bit set. */
    148 	if ( a->a_vals != &slap_dummy_bv &&
    149 		!( a->a_flags & SLAP_ATTR_DONT_FREE_VALS )) {
    150 		if ( a->a_flags & SLAP_ATTR_DONT_FREE_DATA ) {
    151 			free( a->a_vals );
    152 		} else {
    153 			ber_bvarray_free( a->a_vals );
    154 		}
    155 	}
    156 	a->a_desc = NULL;
    157 	a->a_vals = NULL;
    158 	a->a_nvals = NULL;
    159 #ifdef LDAP_COMP_MATCH
    160 	a->a_comp_data = NULL;
    161 #endif
    162 	a->a_flags = 0;
    163 	a->a_numvals = 0;
    164 }
    165 
    166 void
    167 attr_free( Attribute *a )
    168 {
    169 	attr_clean( a );
    170 	ldap_pvt_thread_mutex_lock( &attr_mutex );
    171 	a->a_next = attrs_list;
    172 	attrs_list = a;
    173 	ldap_pvt_thread_mutex_unlock( &attr_mutex );
    174 }
    175 
    176 #ifdef LDAP_COMP_MATCH
    177 void
    178 comp_tree_free( Attribute *a )
    179 {
    180 	Attribute *next;
    181 
    182 	for( ; a != NULL ; a = next ) {
    183 		next = a->a_next;
    184 		if ( component_destructor && a->a_comp_data ) {
    185 			if ( a->a_comp_data->cd_mem_op )
    186 				component_destructor( a->a_comp_data->cd_mem_op );
    187 			free ( a->a_comp_data );
    188 		}
    189 	}
    190 }
    191 #endif
    192 
    193 void
    194 attrs_free( Attribute *a )
    195 {
    196 	if ( a ) {
    197 		Attribute *b = (Attribute *)0xBAD, *tail, *next;
    198 
    199 		/* save tail */
    200 		tail = a;
    201 		do {
    202 			next = a->a_next;
    203 			attr_clean( a );
    204 			a->a_next = b;
    205 			b = a;
    206 			a = next;
    207 		} while ( next );
    208 
    209 		ldap_pvt_thread_mutex_lock( &attr_mutex );
    210 		/* replace NULL with current attr list and let attr list
    211 		 * start from last attribute returned to list */
    212 		tail->a_next = attrs_list;
    213 		attrs_list = b;
    214 		ldap_pvt_thread_mutex_unlock( &attr_mutex );
    215 	}
    216 }
    217 
    218 static void
    219 attr_dup2( Attribute *tmp, Attribute *a )
    220 {
    221 	tmp->a_flags = a->a_flags & SLAP_ATTR_PERSISTENT_FLAGS;
    222 	if ( a->a_vals != NULL ) {
    223 		unsigned	i, j;
    224 
    225 		tmp->a_numvals = a->a_numvals;
    226 		tmp->a_vals = ch_malloc( (tmp->a_numvals + 1) * sizeof(struct berval) );
    227 		for ( i = 0; i < tmp->a_numvals; i++ ) {
    228 			ber_dupbv( &tmp->a_vals[i], &a->a_vals[i] );
    229 			if ( BER_BVISNULL( &tmp->a_vals[i] ) ) break;
    230 			/* FIXME: error? */
    231 		}
    232 		BER_BVZERO( &tmp->a_vals[i] );
    233 
    234 		/* a_nvals must be non null; it may be equal to a_vals */
    235 		assert( a->a_nvals != NULL );
    236 
    237 		if ( a->a_nvals != a->a_vals ) {
    238 
    239 			tmp->a_nvals = ch_malloc( (tmp->a_numvals + 1) * sizeof(struct berval) );
    240 			j = 0;
    241 			if ( i ) {
    242 				for ( ; !BER_BVISNULL( &a->a_nvals[j] ); j++ ) {
    243 					assert( j < i );
    244 					ber_dupbv( &tmp->a_nvals[j], &a->a_nvals[j] );
    245 					if ( BER_BVISNULL( &tmp->a_nvals[j] ) ) break;
    246 					/* FIXME: error? */
    247 				}
    248 				assert( j == i );
    249 			}
    250 			BER_BVZERO( &tmp->a_nvals[j] );
    251 
    252 		} else {
    253 			tmp->a_nvals = tmp->a_vals;
    254 		}
    255 	}
    256 }
    257 
    258 Attribute *
    259 attr_dup( Attribute *a )
    260 {
    261 	Attribute *tmp;
    262 
    263 	if ( a == NULL) return NULL;
    264 
    265 	tmp = attr_alloc( a->a_desc );
    266 	attr_dup2( tmp, a );
    267 	return tmp;
    268 }
    269 
    270 Attribute *
    271 attrs_dup( Attribute *a )
    272 {
    273 	int i;
    274 	Attribute *tmp, *anew;
    275 
    276 	if( a == NULL ) return NULL;
    277 
    278 	/* count them */
    279 	for( tmp=a,i=0; tmp; tmp=tmp->a_next ) {
    280 		i++;
    281 	}
    282 
    283 	anew = attrs_alloc( i );
    284 
    285 	for( tmp=anew; a; a=a->a_next ) {
    286 		tmp->a_desc = a->a_desc;
    287 		attr_dup2( tmp, a );
    288 		tmp=tmp->a_next;
    289 	}
    290 
    291 	return anew;
    292 }
    293 
    294 int
    295 attr_valfind(
    296 	Attribute *a,
    297 	unsigned flags,
    298 	struct berval *val,
    299 	unsigned *slot,
    300 	void *ctx )
    301 {
    302 	struct berval nval = BER_BVNULL, *cval;
    303 	MatchingRule *mr;
    304 	const char *text;
    305 	int match = -1, rc;
    306 	unsigned i, n;
    307 
    308 	if ( flags & SLAP_MR_ORDERING )
    309 		mr = a->a_desc->ad_type->sat_ordering;
    310 	else
    311 		mr = a->a_desc->ad_type->sat_equality;
    312 
    313 	if( !SLAP_IS_MR_ASSERTED_VALUE_NORMALIZED_MATCH( flags ) &&
    314 		mr->smr_normalize )
    315 	{
    316 		rc = (mr->smr_normalize)(
    317 			flags & (SLAP_MR_TYPE_MASK|SLAP_MR_SUBTYPE_MASK|SLAP_MR_VALUE_OF_SYNTAX),
    318 			a->a_desc->ad_type->sat_syntax,
    319 			mr, val, &nval, ctx );
    320 
    321 		if( rc != LDAP_SUCCESS ) {
    322 			return LDAP_INVALID_SYNTAX;
    323 		}
    324 		cval = &nval;
    325 	} else {
    326 		cval = val;
    327 	}
    328 
    329 	n = a->a_numvals;
    330 	if ( (a->a_flags & SLAP_ATTR_SORTED_VALS) && n ) {
    331 		/* Binary search */
    332 		unsigned base = 0;
    333 
    334 		do {
    335 			unsigned pivot = n >> 1;
    336 			i = base + pivot;
    337 			rc = value_match( &match, a->a_desc, mr, flags,
    338 				&a->a_nvals[i], cval, &text );
    339 			if ( rc == LDAP_SUCCESS && match == 0 )
    340 				break;
    341 			if ( match < 0 ) {
    342 				base = i+1;
    343 				n -= pivot+1;
    344 			} else {
    345 				n = pivot;
    346 			}
    347 		} while ( n );
    348 		if ( match < 0 )
    349 			i++;
    350 	} else {
    351 	/* Linear search */
    352 		for ( i = 0; i < n; i++ ) {
    353 			const char *text;
    354 
    355 			rc = ordered_value_match( &match, a->a_desc, mr, flags,
    356 				&a->a_nvals[i], cval, &text );
    357 			if ( rc == LDAP_SUCCESS && match == 0 )
    358 				break;
    359 		}
    360 	}
    361 	if ( match )
    362 		rc = LDAP_NO_SUCH_ATTRIBUTE;
    363 	if ( slot )
    364 		*slot = i;
    365 	if ( nval.bv_val )
    366 		slap_sl_free( nval.bv_val, ctx );
    367 
    368 	return rc;
    369 }
    370 
    371 int
    372 attr_valadd(
    373 	Attribute *a,
    374 	BerVarray vals,
    375 	BerVarray nvals,
    376 	int nn )
    377 {
    378 	int		i;
    379 	BerVarray	v2;
    380 
    381 	v2 = (BerVarray) SLAP_REALLOC( (char *) a->a_vals,
    382 		    (a->a_numvals + nn + 1) * sizeof(struct berval) );
    383 	if( v2 == NULL ) {
    384 		Debug(LDAP_DEBUG_TRACE,
    385 		  "attr_valadd: SLAP_REALLOC failed.\n" );
    386 		return LBER_ERROR_MEMORY;
    387 	}
    388 	a->a_vals = v2;
    389 	if ( nvals ) {
    390 		v2 = (BerVarray) SLAP_REALLOC( (char *) a->a_nvals,
    391 				(a->a_numvals + nn + 1) * sizeof(struct berval) );
    392 		if( v2 == NULL ) {
    393 			Debug(LDAP_DEBUG_TRACE,
    394 			  "attr_valadd: SLAP_REALLOC failed.\n" );
    395 			return LBER_ERROR_MEMORY;
    396 		}
    397 		a->a_nvals = v2;
    398 	} else {
    399 		a->a_nvals = a->a_vals;
    400 	}
    401 
    402 	/* If sorted and old vals exist, must insert */
    403 	if (( a->a_flags & SLAP_ATTR_SORTED_VALS ) && a->a_numvals ) {
    404 		unsigned slot;
    405 		int j, rc;
    406 		v2 = nvals ? nvals : vals;
    407 		for ( i = 0; i < nn; i++ ) {
    408 			rc = attr_valfind( a, SLAP_MR_EQUALITY | SLAP_MR_VALUE_OF_ASSERTION_SYNTAX |
    409 				SLAP_MR_ASSERTED_VALUE_NORMALIZED_MATCH | SLAP_MR_ATTRIBUTE_VALUE_NORMALIZED_MATCH,
    410 				&v2[i], &slot, NULL );
    411 			if ( rc != LDAP_NO_SUCH_ATTRIBUTE ) {
    412 				/* should never happen */
    413 				if ( rc == LDAP_SUCCESS )
    414 					rc = LDAP_TYPE_OR_VALUE_EXISTS;
    415 				return rc;
    416 			}
    417 			for ( j = a->a_numvals; j >= (int)slot; j-- ) {
    418 				a->a_vals[j+1] = a->a_vals[j];
    419 				if ( nvals )
    420 					a->a_nvals[j+1] = a->a_nvals[j];
    421 			}
    422 			ber_dupbv( &a->a_nvals[slot], &v2[i] );
    423 			if ( nvals )
    424 				ber_dupbv( &a->a_vals[slot], &vals[i] );
    425 			a->a_numvals++;
    426 		}
    427 		BER_BVZERO( &a->a_vals[a->a_numvals] );
    428 		if ( a->a_vals != a->a_nvals )
    429 			BER_BVZERO( &a->a_nvals[a->a_numvals] );
    430 	} else {
    431 		v2 = &a->a_vals[a->a_numvals];
    432 		for ( i = 0 ; i < nn; i++ ) {
    433 			ber_dupbv( &v2[i], &vals[i] );
    434 			if ( BER_BVISNULL( &v2[i] ) ) break;
    435 		}
    436 		BER_BVZERO( &v2[i] );
    437 
    438 		if ( nvals ) {
    439 			v2 = &a->a_nvals[a->a_numvals];
    440 			for ( i = 0 ; i < nn; i++ ) {
    441 				ber_dupbv( &v2[i], &nvals[i] );
    442 				if ( BER_BVISNULL( &v2[i] ) ) break;
    443 			}
    444 			BER_BVZERO( &v2[i] );
    445 		}
    446 		a->a_numvals += i;
    447 	}
    448 	return 0;
    449 }
    450 
    451 /*
    452  * attr_merge - merge the given type and value with the list of
    453  * attributes in attrs.
    454  *
    455  * nvals must be NULL if the attribute has no normalizer.
    456  * In this case, a->a_nvals will be set equal to a->a_vals.
    457  *
    458  * returns	0	everything went ok
    459  *		-1	trouble
    460  */
    461 
    462 int
    463 attr_merge(
    464 	Entry		*e,
    465 	AttributeDescription *desc,
    466 	BerVarray	vals,
    467 	BerVarray	nvals )
    468 {
    469 	int i = 0;
    470 
    471 	Attribute	**a;
    472 
    473 	for ( a = &e->e_attrs; *a != NULL; a = &(*a)->a_next ) {
    474 		if (  (*a)->a_desc == desc ) {
    475 			break;
    476 		}
    477 	}
    478 
    479 	if ( *a == NULL ) {
    480 		*a = attr_alloc( desc );
    481 	} else {
    482 		/*
    483 		 * FIXME: if the attribute already exists, the presence
    484 		 * of nvals and the value of (*a)->a_nvals must be consistent
    485 		 */
    486 		assert( ( nvals == NULL && (*a)->a_nvals == (*a)->a_vals )
    487 				|| ( nvals != NULL && (
    488 					( (*a)->a_vals == NULL && (*a)->a_nvals == NULL )
    489 					|| ( (*a)->a_nvals != (*a)->a_vals ) ) ) );
    490 	}
    491 
    492 	if ( vals != NULL ) {
    493 		for ( ; !BER_BVISNULL( &vals[i] ); i++ ) ;
    494 	}
    495 	return attr_valadd( *a, vals, nvals, i );
    496 }
    497 
    498 /*
    499  * if a normalization function is defined for the equality matchingRule
    500  * of desc, the value is normalized and stored in nval; otherwise nval
    501  * is NULL
    502  */
    503 int
    504 attr_normalize(
    505 	AttributeDescription	*desc,
    506 	BerVarray		vals,
    507 	BerVarray		*nvalsp,
    508 	void	 		*memctx )
    509 {
    510 	int		rc = LDAP_SUCCESS;
    511 	BerVarray	nvals = NULL;
    512 
    513 	*nvalsp = NULL;
    514 
    515 	if ( desc->ad_type->sat_equality &&
    516 		desc->ad_type->sat_equality->smr_normalize )
    517 	{
    518 		int	i;
    519 
    520 		for ( i = 0; !BER_BVISNULL( &vals[i] ); i++ );
    521 
    522 		nvals = slap_sl_calloc( sizeof(struct berval), i + 1, memctx );
    523 		for ( i = 0; !BER_BVISNULL( &vals[i] ); i++ ) {
    524 			rc = desc->ad_type->sat_equality->smr_normalize(
    525 					SLAP_MR_VALUE_OF_ATTRIBUTE_SYNTAX,
    526 					desc->ad_type->sat_syntax,
    527 					desc->ad_type->sat_equality,
    528 					&vals[i], &nvals[i], memctx );
    529 
    530 			if ( rc != LDAP_SUCCESS ) {
    531 				BER_BVZERO( &nvals[i + 1] );
    532 				break;
    533 			}
    534 		}
    535 		BER_BVZERO( &nvals[i] );
    536 		*nvalsp = nvals;
    537 	}
    538 
    539 	if ( rc != LDAP_SUCCESS && nvals != NULL ) {
    540 		ber_bvarray_free_x( nvals, memctx );
    541 	}
    542 
    543 	return rc;
    544 }
    545 
    546 int
    547 attr_merge_normalize(
    548 	Entry			*e,
    549 	AttributeDescription	*desc,
    550 	BerVarray		vals,
    551 	void	 		*memctx )
    552 {
    553 	BerVarray	nvals = NULL;
    554 	int		rc;
    555 
    556 	rc = attr_normalize( desc, vals, &nvals, memctx );
    557 	if ( rc == LDAP_SUCCESS ) {
    558 		rc = attr_merge( e, desc, vals, nvals );
    559 		if ( nvals != NULL ) {
    560 			ber_bvarray_free_x( nvals, memctx );
    561 		}
    562 	}
    563 
    564 	return rc;
    565 }
    566 
    567 int
    568 attr_merge_one(
    569 	Entry		*e,
    570 	AttributeDescription *desc,
    571 	struct berval	*val,
    572 	struct berval	*nval )
    573 {
    574 	Attribute	**a;
    575 
    576 	for ( a = &e->e_attrs; *a != NULL; a = &(*a)->a_next ) {
    577 		if ( (*a)->a_desc == desc ) {
    578 			break;
    579 		}
    580 	}
    581 
    582 	if ( *a == NULL ) {
    583 		*a = attr_alloc( desc );
    584 	}
    585 
    586 	return attr_valadd( *a, val, nval, 1 );
    587 }
    588 
    589 /*
    590  * if a normalization function is defined for the equality matchingRule
    591  * of desc, the value is normalized and stored in nval; otherwise nval
    592  * is NULL
    593  */
    594 int
    595 attr_normalize_one(
    596 	AttributeDescription *desc,
    597 	struct berval	*val,
    598 	struct berval	*nval,
    599 	void		*memctx )
    600 {
    601 	int		rc = LDAP_SUCCESS;
    602 
    603 	BER_BVZERO( nval );
    604 
    605 	if ( desc->ad_type->sat_equality &&
    606 		desc->ad_type->sat_equality->smr_normalize )
    607 	{
    608 		rc = desc->ad_type->sat_equality->smr_normalize(
    609 				SLAP_MR_VALUE_OF_ATTRIBUTE_SYNTAX,
    610 				desc->ad_type->sat_syntax,
    611 				desc->ad_type->sat_equality,
    612 				val, nval, memctx );
    613 
    614 		if ( rc != LDAP_SUCCESS ) {
    615 			return rc;
    616 		}
    617 	}
    618 
    619 	return rc;
    620 }
    621 
    622 int
    623 attr_merge_normalize_one(
    624 	Entry		*e,
    625 	AttributeDescription *desc,
    626 	struct berval	*val,
    627 	void		*memctx )
    628 {
    629 	struct berval	nval = BER_BVNULL;
    630 	struct berval	*nvalp = NULL;
    631 	int		rc;
    632 
    633 	rc = attr_normalize_one( desc, val, &nval, memctx );
    634 	if ( rc == LDAP_SUCCESS && !BER_BVISNULL( &nval ) ) {
    635 		nvalp = &nval;
    636 	}
    637 
    638 	rc = attr_merge_one( e, desc, val, nvalp );
    639 	if ( nvalp != NULL ) {
    640 		slap_sl_free( nval.bv_val, memctx );
    641 	}
    642 	return rc;
    643 }
    644 
    645 /*
    646  * attrs_find - find attribute(s) by AttributeDescription
    647  * returns next attribute which is subtype of provided description.
    648  */
    649 
    650 Attribute *
    651 attrs_find(
    652     Attribute	*a,
    653 	AttributeDescription *desc )
    654 {
    655 	for ( ; a != NULL; a = a->a_next ) {
    656 		if ( is_ad_subtype( a->a_desc, desc ) ) {
    657 			return( a );
    658 		}
    659 	}
    660 
    661 	return( NULL );
    662 }
    663 
    664 /*
    665  * attr_find - find attribute by type
    666  */
    667 
    668 Attribute *
    669 attr_find(
    670     Attribute	*a,
    671 	AttributeDescription *desc )
    672 {
    673 	for ( ; a != NULL; a = a->a_next ) {
    674 		if ( a->a_desc == desc ) {
    675 			return( a );
    676 		}
    677 	}
    678 
    679 	return( NULL );
    680 }
    681 
    682 /*
    683  * attr_delete - delete the attribute type in list pointed to by attrs
    684  * return	0	deleted ok
    685  * 		1	not found in list a
    686  * 		-1	something bad happened
    687  */
    688 
    689 int
    690 attr_delete(
    691     Attribute	**attrs,
    692 	AttributeDescription *desc )
    693 {
    694 	Attribute	**a;
    695 
    696 	for ( a = attrs; *a != NULL; a = &(*a)->a_next ) {
    697 		if ( (*a)->a_desc == desc ) {
    698 			Attribute	*save = *a;
    699 			*a = (*a)->a_next;
    700 			attr_free( save );
    701 
    702 			return LDAP_SUCCESS;
    703 		}
    704 	}
    705 
    706 	return LDAP_NO_SUCH_ATTRIBUTE;
    707 }
    708 
    709 int
    710 attr_init( void )
    711 {
    712 	ldap_pvt_thread_mutex_init( &attr_mutex );
    713 	return 0;
    714 }
    715 
    716 int
    717 attr_destroy( void )
    718 {
    719 	slap_list *a;
    720 
    721 	for ( a=attr_chunks; a; a=attr_chunks ) {
    722 		attr_chunks = a->next;
    723 		free( a );
    724 	}
    725 	ldap_pvt_thread_mutex_destroy( &attr_mutex );
    726 	return 0;
    727 }
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