bind9/lib/isc/include/isc/ht.h
Evan Hunt 10accd6260 clean up uses of ISC_R_NOMEMORY
the isc_mem allocation functions can no longer fail; as a result,
ISC_R_NOMEMORY is now rarely used: only when an external library
such as libjson-c or libfstrm could return NULL. (even in
these cases, arguably we should assert rather than returning
ISC_R_NOMEMORY.)

code and comments that mentioned ISC_R_NOMEMORY have been
cleaned up, and the following functions have been changed to
type void, since (in most cases) the only value they could
return was ISC_R_SUCCESS:

- dns_dns64_create()
- dns_dyndb_create()
- dns_ipkeylist_resize()
- dns_kasp_create()
- dns_kasp_key_create()
- dns_keystore_create()
- dns_order_create()
- dns_order_add()
- dns_peerlist_new()
- dns_tkeyctx_create()
- dns_view_create()
- dns_zone_setorigin()
- dns_zone_setfile()
- dns_zone_setstream()
- dns_zone_getdbtype()
- dns_zone_setjournal()
- dns_zone_setkeydirectory()
- isc_lex_openstream()
- isc_portset_create()
- isc_symtab_create()

(the exception is dns_view_create(), which could have returned
other error codes in the event of a crypto library failure when
calling isc_file_sanitize(), but that should be a RUNTIME_CHECK
anyway.)
2025-01-23 15:54:57 -08:00

190 lines
4.2 KiB
C

/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* SPDX-License-Identifier: MPL-2.0
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/* ! \file */
#pragma once
#include <inttypes.h>
#include <string.h>
#include <isc/result.h>
#include <isc/types.h>
typedef struct isc_ht isc_ht_t;
typedef struct isc_ht_iter isc_ht_iter_t;
enum { ISC_HT_CASE_SENSITIVE = 0x00, ISC_HT_CASE_INSENSITIVE = 0x01 };
/*%
* Initialize hashtable at *htp, using memory context and size of (1<<bits)
*
* If 'options' contains ISC_HT_CASE_INSENSITIVE, then upper- and lower-case
* letters in key values will generate the same hash values; this can be used
* when the key for a hash table is a DNS name.
*
* Requires:
*\li 'htp' is not NULL and '*htp' is NULL.
*\li 'mctx' is a valid memory context.
*\li 'bits' >=1 and 'bits' <=32
*
*/
void
isc_ht_init(isc_ht_t **htp, isc_mem_t *mctx, uint8_t bits,
unsigned int options);
/*%
* Destroy hashtable, freeing everything
*
* Requires:
* \li '*htp' is valid hashtable
*/
void
isc_ht_destroy(isc_ht_t **htp);
/*%
* Add a node to hashtable, pointed by binary key 'key' of size 'keysize';
* set its value to 'value'
*
* Requires:
*\li 'ht' is a valid hashtable
*\li write-lock
*
* Returns:
*\li #ISC_R_EXISTS -- node of the same key already exists
*\li #ISC_R_SUCCESS -- all is well.
*/
isc_result_t
isc_ht_add(isc_ht_t *ht, const unsigned char *key, const uint32_t keysize,
void *value);
/*%
* Find a node matching 'key'/'keysize' in hashtable 'ht';
* if found, set '*valuep' to its value. (If 'valuep' is NULL,
* then simply return SUCCESS or NOTFOUND to indicate whether the
* key exists in the hashtable.)
*
* Requires:
* \li 'ht' is a valid hashtable
* \li read-lock
*
* Returns:
* \li #ISC_R_SUCCESS -- success
* \li #ISC_R_NOTFOUND -- key not found
*/
isc_result_t
isc_ht_find(const isc_ht_t *ht, const unsigned char *key,
const uint32_t keysize, void **valuep);
/*%
* Delete node from hashtable
*
* Requires:
*\li ht is a valid hashtable
*\li write-lock
*
* Returns:
*\li #ISC_R_NOTFOUND -- key not found
*\li #ISC_R_SUCCESS -- all is well
*/
isc_result_t
isc_ht_delete(isc_ht_t *ht, const unsigned char *key, const uint32_t keysize);
/*%
* Create an iterator for the hashtable; point '*itp' to it.
*
* Requires:
*\li 'ht' is a valid hashtable
*\li 'itp' is non NULL and '*itp' is NULL.
*/
void
isc_ht_iter_create(isc_ht_t *ht, isc_ht_iter_t **itp);
/*%
* Destroy the iterator '*itp', set it to NULL
*
* Requires:
*\li 'itp' is non NULL and '*itp' is non NULL.
*/
void
isc_ht_iter_destroy(isc_ht_iter_t **itp);
/*%
* Set an iterator to the first entry.
*
* Requires:
*\li 'it' is non NULL.
*
* Returns:
* \li #ISC_R_SUCCESS -- success
* \li #ISC_R_NOMORE -- no data in the hashtable
*/
isc_result_t
isc_ht_iter_first(isc_ht_iter_t *it);
/*%
* Set an iterator to the next entry.
*
* Requires:
*\li 'it' is non NULL.
*
* Returns:
* \li #ISC_R_SUCCESS -- success
* \li #ISC_R_NOMORE -- end of hashtable reached
*/
isc_result_t
isc_ht_iter_next(isc_ht_iter_t *it);
/*%
* Delete current entry and set an iterator to the next entry.
*
* Requires:
*\li 'it' is non NULL.
*
* Returns:
* \li #ISC_R_SUCCESS -- success
* \li #ISC_R_NOMORE -- end of hashtable reached
*/
isc_result_t
isc_ht_iter_delcurrent_next(isc_ht_iter_t *it);
/*%
* Set 'value' to the current value under the iterator
*
* Requires:
*\li 'it' is non NULL.
*\li 'valuep' is non NULL and '*valuep' is NULL.
*/
void
isc_ht_iter_current(isc_ht_iter_t *it, void **valuep);
/*%
* Set 'key' and 'keysize to the current key and keysize for the value
* under the iterator
*
* Requires:
*\li 'it' is non NULL.
*\li 'key' is non NULL and '*key' is NULL.
*\li 'keysize' is non NULL.
*/
void
isc_ht_iter_currentkey(isc_ht_iter_t *it, unsigned char **key, size_t *keysize);
/*%
* Returns the number of items in the hashtable.
*
* Requires:
*\li 'ht' is a valid hashtable
*/
size_t
isc_ht_count(const isc_ht_t *ht);