/*
* Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* 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 http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*
* Portions Copyright (C) 2001 Nominum, Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NOMINUM DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef ISCCC_SYMTAB_H
#define ISCCC_SYMTAB_H 1
/*****
***** Module Info
*****/
/*! \file isccc/symtab.h
* \brief
* Provides a simple memory-based symbol table.
*
* Keys are C strings. A type may be specified when looking up,
* defining, or undefining. A type value of 0 means "match any type";
* any other value will only match the given type.
*
* It's possible that a client will attempt to define a <key, type,
* value> tuple when a tuple with the given key and type already
* exists in the table. What to do in this case is specified by the
* client. Possible policies are:
*
*\li isccc_symexists_reject Disallow the define, returning #ISC_R_EXISTS
*\li isccc_symexists_replace Replace the old value with the new. The
* undefine action (if provided) will be called
* with the old <key, type, value> tuple.
*\li isccc_symexists_add Add the new tuple, leaving the old tuple in
* the table. Subsequent lookups will retrieve
* the most-recently-defined tuple.
*
* A lookup of a key using type 0 will return the most-recently
* defined symbol with that key. An undefine of a key using type 0
* will undefine the most-recently defined symbol with that key.
* Trying to define a key with type 0 is illegal.
*
* The symbol table library does not make a copy the key field, so the
* caller must ensure that any key it passes to isccc_symtab_define()
* will not change until it calls isccc_symtab_undefine() or
* isccc_symtab_destroy().
*
* A user-specified action will be called (if provided) when a symbol
* is undefined. It can be used to free memory associated with keys
* and/or values.
*/
/***
*** Imports.
***/
#include <isc/lang.h>
#include <isccc/types.h>
/***
*** Symbol Tables.
***/
typedef union isccc_symvalue {
void * as_pointer;
int as_integer;
unsigned int as_uinteger;
} isccc_symvalue_t;
typedef void (*isccc_symtabundefaction_t)(char *key, unsigned int type,
isccc_symvalue_t value, void *userarg);
typedef isc_boolean_t (*isccc_symtabforeachaction_t)(char *key,
unsigned int type,
isccc_symvalue_t value,
void *userarg);
typedef enum {
isccc_symexists_reject = 0,
isccc_symexists_replace = 1,
isccc_symexists_add = 2
} isccc_symexists_t;
ISC_LANG_BEGINDECLS
isc_result_t
isccc_symtab_create(unsigned int size,
isccc_symtabundefaction_t undefine_action, void *undefine_arg,
isc_boolean_t case_sensitive, isccc_symtab_t **symtabp);
void
isccc_symtab_destroy(isccc_symtab_t **symtabp);
isc_result_t
isccc_symtab_lookup(isccc_symtab_t *symtab, const char *key, unsigned int type,
isccc_symvalue_t *value);
isc_result_t
isccc_symtab_define(isccc_symtab_t *symtab, char *key, unsigned int type,
isccc_symvalue_t value, isccc_symexists_t exists_policy);
isc_result_t
isccc_symtab_undefine(isccc_symtab_t *symtab, const char *key, unsigned int type);
void
isccc_symtab_foreach(isccc_symtab_t *symtab, isccc_symtabforeachaction_t action,
void *arg);
ISC_LANG_ENDDECLS
#endif /* ISCCC_SYMTAB_H */
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