text: /* delete.c - bdb backend delete routine */
  /* $OpenLDAP$ */
  /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   *
   * Copyright 2000-2016 The OpenLDAP Foundation.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted only as authorized by the OpenLDAP
   * Public License.
   *
   * A copy of this license is available in the file LICENSE in the
   * top-level directory of the distribution or, alternatively, at
   * <http://www.OpenLDAP.org/license.html>.
   */
  
  #include "portable.h"
  
  #include <stdio.h>
  #include <ac/string.h>
  
  #include "lutil.h"
  #include "back-bdb.h"
  
  int
  bdb_delete( Operation *op, SlapReply *rs )
  {
  	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
  	Entry	*matched = NULL;
  	struct berval	pdn = {0, NULL};
  	Entry	*e = NULL;
  	Entry	*p = NULL;
  	EntryInfo	*ei = NULL, *eip = NULL;
  	int		manageDSAit = get_manageDSAit( op );
  	AttributeDescription *children = slap_schema.si_ad_children;
  	AttributeDescription *entry = slap_schema.si_ad_entry;
  	DB_TXN		*ltid = NULL, *lt2;
  	struct bdb_op_info opinfo = {{{ 0 }}};
  	ID	eid;
  
  	DB_LOCK		lock, plock;
  
  	int		num_retries = 0;
  
  	int     rc;
  
  	LDAPControl **preread_ctrl = NULL;
  	LDAPControl *ctrls[SLAP_MAX_RESPONSE_CONTROLS];
  	int num_ctrls = 0;
  
  	int	parent_is_glue = 0;
  	int parent_is_leaf = 0;
  
  	Debug( LDAP_DEBUG_ARGS, "==> " LDAP_XSTRING(bdb_delete) ": %s\n",
  		op->o_req_dn.bv_val, 0, 0 );
  
  #ifdef LDAP_X_TXN
  	if( op->o_txnSpec && txn_preop( op, rs ))
  		return rs->sr_err;
  #endif
  
  	ctrls[num_ctrls] = 0;
  
  	/* allocate CSN */
  	if ( BER_BVISNULL( &op->o_csn ) ) {
  		struct berval csn;
  		char csnbuf[LDAP_PVT_CSNSTR_BUFSIZE];
  
  		csn.bv_val = csnbuf;
  		csn.bv_len = sizeof(csnbuf);
  		slap_get_csn( op, &csn, 1 );
  	}
  
  	if( 0 ) {
  retry:	/* transaction retry */
  		if( e != NULL ) {
  			bdb_unlocked_cache_return_entry_w(&bdb->bi_cache, e);
  			e = NULL;
  		}
  		if( p != NULL ) {
  			bdb_unlocked_cache_return_entry_r(&bdb->bi_cache, p);
  			p = NULL;
  		}
  		Debug( LDAP_DEBUG_TRACE,
  			"==> " LDAP_XSTRING(bdb_delete) ": retrying...\n",
  			0, 0, 0 );
  		rs->sr_err = TXN_ABORT( ltid );
  		ltid = NULL;
  		LDAP_SLIST_REMOVE( &op->o_extra, &opinfo.boi_oe, OpExtra, oe_next );
  		opinfo.boi_oe.oe_key = NULL;
  		op->o_do_not_cache = opinfo.boi_acl_cache;
  		if( rs->sr_err != 0 ) {
  			rs->sr_err = LDAP_OTHER;
  			rs->sr_text = "internal error";
  			goto return_results;
  		}
  		if ( op->o_abandon ) {
  			rs->sr_err = SLAPD_ABANDON;
  			goto return_results;
  		}
  		parent_is_glue = 0;
  		parent_is_leaf = 0;
  		bdb_trans_backoff( ++num_retries );
  	}
  
  	/* begin transaction */
  	{
  		int tflags = bdb->bi_db_opflags;
  		if ( get_lazyCommit( op ))
  			tflags |= DB_TXN_NOSYNC;
  		rs->sr_err = TXN_BEGIN( bdb->bi_dbenv, NULL, &ltid, tflags );
  	}
  	Debug( LDAP_DEBUG_TRACE, LDAP_XSTRING(bdb_delete) ": txn1 id: %x\n",
  		ltid->id(ltid), 0, 0 );
  	rs->sr_text = NULL;
  	if( rs->sr_err != 0 ) {
  		Debug( LDAP_DEBUG_TRACE,
  			LDAP_XSTRING(bdb_delete) ": txn_begin failed: "
  			"%s (%d)\n", db_strerror(rs->sr_err), rs->sr_err, 0 );
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "internal error";
  		goto return_results;
  	}
  
  	opinfo.boi_oe.oe_key = bdb;
  	opinfo.boi_txn = ltid;
  	opinfo.boi_err = 0;
  	opinfo.boi_acl_cache = op->o_do_not_cache;
  	LDAP_SLIST_INSERT_HEAD( &op->o_extra, &opinfo.boi_oe, oe_next );
  
  	if ( !be_issuffix( op->o_bd, &op->o_req_ndn ) ) {
  		dnParent( &op->o_req_ndn, &pdn );
  	}
  
  	/* get entry */
  	rs->sr_err = bdb_dn2entry( op, ltid, &op->o_req_ndn, &ei, 1,
  		&lock );
  
  	switch( rs->sr_err ) {
  	case 0:
  	case DB_NOTFOUND:
  		break;
  	case DB_LOCK_DEADLOCK:
  	case DB_LOCK_NOTGRANTED:
  		goto retry;
  	case LDAP_BUSY:
  		rs->sr_text = "ldap server busy";
  		goto return_results;
  	default:
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "internal error";
  		goto return_results;
  	}
  
  	if ( rs->sr_err == 0 ) {
  		e = ei->bei_e;
  		eip = ei->bei_parent;
  	} else {
  		matched = ei->bei_e;
  	}
  
  	/* FIXME : dn2entry() should return non-glue entry */
  	if ( e == NULL || ( !manageDSAit && is_entry_glue( e ))) {
  		Debug( LDAP_DEBUG_ARGS,
  			"<=- " LDAP_XSTRING(bdb_delete) ": no such object %s\n",
  			op->o_req_dn.bv_val, 0, 0);
  
  		if ( matched != NULL ) {
  			rs->sr_matched = ch_strdup( matched->e_dn );
  			rs->sr_ref = is_entry_referral( matched )
  				? get_entry_referrals( op, matched )
  				: NULL;
  			bdb_unlocked_cache_return_entry_r(&bdb->bi_cache, matched);
  			matched = NULL;
  
  		} else {
  			rs->sr_ref = referral_rewrite( default_referral, NULL,
  					&op->o_req_dn, LDAP_SCOPE_DEFAULT );
  		}
  
  		rs->sr_err = LDAP_REFERRAL;
  		rs->sr_flags = REP_MATCHED_MUSTBEFREED | REP_REF_MUSTBEFREED;
  		goto return_results;
  	}
  
  	rc = bdb_cache_find_id( op, ltid, eip->bei_id, &eip, 0, &plock );
  	switch( rc ) {
  	case DB_LOCK_DEADLOCK:
  	case DB_LOCK_NOTGRANTED:
  		goto retry;
  	case 0:
  	case DB_NOTFOUND:
  		break;
  	default:
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "internal error";
  		goto return_results;
  	}
  	if ( eip ) p = eip->bei_e;
  
  	if ( pdn.bv_len != 0 ) {
  		if( p == NULL || !bvmatch( &pdn, &p->e_nname )) {
  			Debug( LDAP_DEBUG_TRACE,
  				"<=- " LDAP_XSTRING(bdb_delete) ": parent "
  				"does not exist\n", 0, 0, 0 );
  			rs->sr_err = LDAP_OTHER;
  			rs->sr_text = "could not locate parent of entry";
  			goto return_results;
  		}
  
  		/* check parent for "children" acl */
  		rs->sr_err = access_allowed( op, p,
  			children, NULL, ACL_WDEL, NULL );
  
  		if ( !rs->sr_err  ) {
  			switch( opinfo.boi_err ) {
  			case DB_LOCK_DEADLOCK:
  			case DB_LOCK_NOTGRANTED:
  				goto retry;
  			}
  
  			Debug( LDAP_DEBUG_TRACE,
  				"<=- " LDAP_XSTRING(bdb_delete) ": no write "
  				"access to parent\n", 0, 0, 0 );
  			rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
  			rs->sr_text = "no write access to parent";
  			goto return_results;
  		}
  
  	} else {
  		/* no parent, must be root to delete */
  		if( ! be_isroot( op ) ) {
  			if ( be_issuffix( op->o_bd, (struct berval *)&slap_empty_bv )
  				|| be_shadow_update( op ) ) {
  				p = (Entry *)&slap_entry_root;
  
  				/* check parent for "children" acl */
  				rs->sr_err = access_allowed( op, p,
  					children, NULL, ACL_WDEL, NULL );
  
  				p = NULL;
  
  				if ( !rs->sr_err  ) {
  					switch( opinfo.boi_err ) {
  					case DB_LOCK_DEADLOCK:
  					case DB_LOCK_NOTGRANTED:
  						goto retry;
  					}
  
  					Debug( LDAP_DEBUG_TRACE,
  						"<=- " LDAP_XSTRING(bdb_delete)
  						": no access to parent\n",
  						0, 0, 0 );
  					rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
  					rs->sr_text = "no write access to parent";
  					goto return_results;
  				}
  
  			} else {
  				Debug( LDAP_DEBUG_TRACE,
  					"<=- " LDAP_XSTRING(bdb_delete)
  					": no parent and not root\n", 0, 0, 0 );
  				rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
  				goto return_results;
  			}
  		}
  	}
  
  	if ( get_assert( op ) &&
  		( test_filter( op, e, get_assertion( op )) != LDAP_COMPARE_TRUE ))
  	{
  		rs->sr_err = LDAP_ASSERTION_FAILED;
  		goto return_results;
  	}
  
  	rs->sr_err = access_allowed( op, e,
  		entry, NULL, ACL_WDEL, NULL );
  
  	if ( !rs->sr_err  ) {
  		switch( opinfo.boi_err ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		}
  
  		Debug( LDAP_DEBUG_TRACE,
  			"<=- " LDAP_XSTRING(bdb_delete) ": no write access "
  			"to entry\n", 0, 0, 0 );
  		rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
  		rs->sr_text = "no write access to entry";
  		goto return_results;
  	}
  
  	if ( !manageDSAit && is_entry_referral( e ) ) {
  		/* entry is a referral, don't allow delete */
  		rs->sr_ref = get_entry_referrals( op, e );
  
  		Debug( LDAP_DEBUG_TRACE,
  			LDAP_XSTRING(bdb_delete) ": entry is referral\n",
  			0, 0, 0 );
  
  		rs->sr_err = LDAP_REFERRAL;
  		rs->sr_matched = ch_strdup( e->e_name.bv_val );
  		rs->sr_flags = REP_MATCHED_MUSTBEFREED | REP_REF_MUSTBEFREED;
  		goto return_results;
  	}
  
  	/* pre-read */
  	if( op->o_preread ) {
  		if( preread_ctrl == NULL ) {
  			preread_ctrl = &ctrls[num_ctrls++];
  			ctrls[num_ctrls] = NULL;
  		}
  		if( slap_read_controls( op, rs, e,
  			&slap_pre_read_bv, preread_ctrl ) )
  		{
  			Debug( LDAP_DEBUG_TRACE,
  				"<=- " LDAP_XSTRING(bdb_delete) ": pre-read "
  				"failed!\n", 0, 0, 0 );
  			if ( op->o_preread & SLAP_CONTROL_CRITICAL ) {
  				/* FIXME: is it correct to abort
  				 * operation if control fails? */
  				goto return_results;
  			}
  		}
  	}
  
  	/* nested transaction */
  	rs->sr_err = TXN_BEGIN( bdb->bi_dbenv, ltid, &lt2, 
  		bdb->bi_db_opflags );
  	rs->sr_text = NULL;
  	if( rs->sr_err != 0 ) {
  		Debug( LDAP_DEBUG_TRACE,
  			LDAP_XSTRING(bdb_delete) ": txn_begin(2) failed: "
  			"%s (%d)\n", db_strerror(rs->sr_err), rs->sr_err, 0 );
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "internal error";
  		goto return_results;
  	}
  	Debug( LDAP_DEBUG_TRACE, LDAP_XSTRING(bdb_delete) ": txn2 id: %x\n",
  		lt2->id(lt2), 0, 0 );
  
  	BDB_LOG_PRINTF( bdb->bi_dbenv, lt2, "slapd Starting delete %s(%d)",
  		e->e_nname.bv_val, e->e_id );
  
  	/* Can't do it if we have kids */
  	rs->sr_err = bdb_cache_children( op, lt2, e );
  	if( rs->sr_err != DB_NOTFOUND ) {
  		switch( rs->sr_err ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		case 0:
  			Debug(LDAP_DEBUG_ARGS,
  				"<=- " LDAP_XSTRING(bdb_delete)
  				": non-leaf %s\n",
  				op->o_req_dn.bv_val, 0, 0);
  			rs->sr_err = LDAP_NOT_ALLOWED_ON_NONLEAF;
  			rs->sr_text = "subordinate objects must be deleted first";
  			break;
  		default:
  			Debug(LDAP_DEBUG_ARGS,
  				"<=- " LDAP_XSTRING(bdb_delete)
  				": has_children failed: %s (%d)\n",
  				db_strerror(rs->sr_err), rs->sr_err, 0 );
  			rs->sr_err = LDAP_OTHER;
  			rs->sr_text = "internal error";
  		}
  		goto return_results;
  	}
  
  	/* delete from dn2id */
  	rs->sr_err = bdb_dn2id_delete( op, lt2, eip, e );
  	if ( rs->sr_err != 0 ) {
  		Debug(LDAP_DEBUG_TRACE,
  			"<=- " LDAP_XSTRING(bdb_delete) ": dn2id failed: "
  			"%s (%d)\n", db_strerror(rs->sr_err), rs->sr_err, 0 );
  		switch( rs->sr_err ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		}
  		rs->sr_text = "DN index delete failed";
  		rs->sr_err = LDAP_OTHER;
  		goto return_results;
  	}
  
  	/* delete indices for old attributes */
  	rs->sr_err = bdb_index_entry_del( op, lt2, e );
  	if ( rs->sr_err != LDAP_SUCCESS ) {
  		Debug(LDAP_DEBUG_TRACE,
  			"<=- " LDAP_XSTRING(bdb_delete) ": index failed: "
  			"%s (%d)\n", db_strerror(rs->sr_err), rs->sr_err, 0 );
  		switch( rs->sr_err ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		}
  		rs->sr_text = "entry index delete failed";
  		rs->sr_err = LDAP_OTHER;
  		goto return_results;
  	}
  
  	/* fixup delete CSN */
  	if ( !SLAP_SHADOW( op->o_bd )) {
  		struct berval vals[2];
  
  		assert( !BER_BVISNULL( &op->o_csn ) );
  		vals[0] = op->o_csn;
  		BER_BVZERO( &vals[1] );
  		rs->sr_err = bdb_index_values( op, lt2, slap_schema.si_ad_entryCSN,
  			vals, 0, SLAP_INDEX_ADD_OP );
  	if ( rs->sr_err != LDAP_SUCCESS ) {
  			switch( rs->sr_err ) {
  			case DB_LOCK_DEADLOCK:
  			case DB_LOCK_NOTGRANTED:
  				goto retry;
  			}
  			rs->sr_text = "entryCSN index update failed";
  			rs->sr_err = LDAP_OTHER;
  			goto return_results;
  		}
  	}
  
  	/* delete from id2entry */
  	rs->sr_err = bdb_id2entry_delete( op->o_bd, lt2, e );
  	if ( rs->sr_err != 0 ) {
  		Debug( LDAP_DEBUG_TRACE,
  			"<=- " LDAP_XSTRING(bdb_delete) ": id2entry failed: "
  			"%s (%d)\n", db_strerror(rs->sr_err), rs->sr_err, 0 );
  		switch( rs->sr_err ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		}
  		rs->sr_text = "entry delete failed";
  		rs->sr_err = LDAP_OTHER;
  		goto return_results;
  	}
  
  	if ( pdn.bv_len != 0 ) {
  		parent_is_glue = is_entry_glue(p);
  		rs->sr_err = bdb_cache_children( op, lt2, p );
  		if ( rs->sr_err != DB_NOTFOUND ) {
  			switch( rs->sr_err ) {
  			case DB_LOCK_DEADLOCK:
  			case DB_LOCK_NOTGRANTED:
  				goto retry;
  			case 0:
  				break;
  			default:
  				Debug(LDAP_DEBUG_ARGS,
  					"<=- " LDAP_XSTRING(bdb_delete)
  					": has_children failed: %s (%d)\n",
  					db_strerror(rs->sr_err), rs->sr_err, 0 );
  				rs->sr_err = LDAP_OTHER;
  				rs->sr_text = "internal error";
  				goto return_results;
  			}
  			parent_is_leaf = 1;
  		}
  		bdb_unlocked_cache_return_entry_r(&bdb->bi_cache, p);
  		p = NULL;
  	}
  
  	BDB_LOG_PRINTF( bdb->bi_dbenv, lt2, "slapd Commit1 delete %s(%d)",
  		e->e_nname.bv_val, e->e_id );
  
  	if ( TXN_COMMIT( lt2, 0 ) != 0 ) {
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "txn_commit(2) failed";
  		goto return_results;
  	}
  
  	eid = e->e_id;
  
  #if 0	/* Do we want to reclaim deleted IDs? */
  	ldap_pvt_thread_mutex_lock( &bdb->bi_lastid_mutex );
  	if ( e->e_id == bdb->bi_lastid ) {
  		bdb_last_id( op->o_bd, ltid );
  	}
  	ldap_pvt_thread_mutex_unlock( &bdb->bi_lastid_mutex );
  #endif
  
  	if( op->o_noop ) {
  		if ( ( rs->sr_err = TXN_ABORT( ltid ) ) != 0 ) {
  			rs->sr_text = "txn_abort (no-op) failed";
  		} else {
  			rs->sr_err = LDAP_X_NO_OPERATION;
  			ltid = NULL;
  			goto return_results;
  		}
  	} else {
  
  		BDB_LOG_PRINTF( bdb->bi_dbenv, ltid, "slapd Cache delete %s(%d)",
  			e->e_nname.bv_val, e->e_id );
  
  		rc = bdb_cache_delete( bdb, e, ltid, &lock );
  		switch( rc ) {
  		case DB_LOCK_DEADLOCK:
  		case DB_LOCK_NOTGRANTED:
  			goto retry;
  		}
  
  		rs->sr_err = TXN_COMMIT( ltid, 0 );
  	}
  	ltid = NULL;
  	LDAP_SLIST_REMOVE( &op->o_extra, &opinfo.boi_oe, OpExtra, oe_next );
  	opinfo.boi_oe.oe_key = NULL;
  
  	BDB_LOG_PRINTF( bdb->bi_dbenv, NULL, "slapd Committed delete %s(%d)",
  		e->e_nname.bv_val, e->e_id );
  
  	if( rs->sr_err != 0 ) {
  		Debug( LDAP_DEBUG_TRACE,
  			LDAP_XSTRING(bdb_delete) ": txn_%s failed: %s (%d)\n",
  			op->o_noop ? "abort (no-op)" : "commit",
  			db_strerror(rs->sr_err), rs->sr_err );
  		rs->sr_err = LDAP_OTHER;
  		rs->sr_text = "commit failed";
  
  		goto return_results;
  	}
  
  	Debug( LDAP_DEBUG_TRACE,
  		LDAP_XSTRING(bdb_delete) ": deleted%s id=%08lx dn=\"%s\"\n",
  		op->o_noop ? " (no-op)" : "",
  		eid, op->o_req_dn.bv_val );
  	rs->sr_err = LDAP_SUCCESS;
  	rs->sr_text = NULL;
  	if( num_ctrls ) rs->sr_ctrls = ctrls;
  
  return_results:
  	if ( rs->sr_err == LDAP_SUCCESS && parent_is_glue && parent_is_leaf ) {
  		op->o_delete_glue_parent = 1;
  	}
  
  	if ( p )
  		bdb_unlocked_cache_return_entry_r(&bdb->bi_cache, p);
  
  	/* free entry */
  	if( e != NULL ) {
  		if ( rs->sr_err == LDAP_SUCCESS ) {
  			/* Free the EntryInfo and the Entry */
  			bdb_cache_entryinfo_lock( BEI(e) );
  			bdb_cache_delete_cleanup( &bdb->bi_cache, BEI(e) );
  		} else {
  			bdb_unlocked_cache_return_entry_w(&bdb->bi_cache, e);
  		}
  	}
  
  	if( ltid != NULL ) {
  		TXN_ABORT( ltid );
  	}
  	if ( opinfo.boi_oe.oe_key ) {
  		LDAP_SLIST_REMOVE( &op->o_extra, &opinfo.boi_oe, OpExtra, oe_next );
  	}
  
  	send_ldap_result( op, rs );
  	slap_graduate_commit_csn( op );
  
  	if( preread_ctrl != NULL && (*preread_ctrl) != NULL ) {
  		slap_sl_free( (*preread_ctrl)->ldctl_value.bv_val, op->o_tmpmemctx );
  		slap_sl_free( *preread_ctrl, op->o_tmpmemctx );
  	}
  
  	if( rs->sr_err == LDAP_SUCCESS && bdb->bi_txn_cp_kbyte ) {
  		TXN_CHECKPOINT( bdb->bi_dbenv,
  			bdb->bi_txn_cp_kbyte, bdb->bi_txn_cp_min, 0 );
  	}
  	return rs->sr_err;
  }
  