/*
* Portions Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
* Portions Copyright (C) 2001 Internet Software Consortium.
*
* 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.
*
* 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.
*/
/* $Id: symtab.c,v 1.11 2007/09/13 04:45:18 each Exp $ */
/*! \file */
#include <config.h>
#include <ctype.h>
#include <stdlib.h>
#include <isc/assertions.h>
#include <isc/magic.h>
#include <isc/string.h>
#include <isccc/result.h>
#include <isccc/symtab.h>
#include <isccc/util.h>
typedef struct elt {
char * key;
unsigned int type;
isccc_symvalue_t value;
ISC_LINK(struct elt) link;
} elt_t;
typedef ISC_LIST(elt_t) eltlist_t;
#define SYMTAB_MAGIC ISC_MAGIC('S', 'y', 'm', 'T')
#define VALID_SYMTAB(st) ISC_MAGIC_VALID(st, SYMTAB_MAGIC)
struct isccc_symtab {
unsigned int magic;
unsigned int size;
eltlist_t * table;
isccc_symtabundefaction_t undefine_action;
void * undefine_arg;
isc_boolean_t case_sensitive;
};
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)
{
isccc_symtab_t *symtab;
unsigned int i;
REQUIRE(symtabp != NULL && *symtabp == NULL);
REQUIRE(size > 0); /* Should be prime. */
symtab = malloc(sizeof(*symtab));
if (symtab == NULL)
return (ISC_R_NOMEMORY);
symtab->table = malloc(size * sizeof(eltlist_t));
if (symtab->table == NULL) {
free(symtab);
return (ISC_R_NOMEMORY);
}
for (i = 0; i < size; i++)
ISC_LIST_INIT(symtab->table[i]);
symtab->size = size;
symtab->undefine_action = undefine_action;
symtab->undefine_arg = undefine_arg;
symtab->case_sensitive = case_sensitive;
symtab->magic = SYMTAB_MAGIC;
*symtabp = symtab;
return (ISC_R_SUCCESS);
}
static inline void
free_elt(isccc_symtab_t *symtab, unsigned int bucket, elt_t *elt) {
ISC_LIST_UNLINK(symtab->table[bucket], elt, link);
if (symtab->undefine_action != NULL)
(symtab->undefine_action)(elt->key, elt->type, elt->value,
symtab->undefine_arg);
free(elt);
}
void
isccc_symtab_destroy(isccc_symtab_t **symtabp) {
isccc_symtab_t *symtab;
unsigned int i;
elt_t *elt, *nelt;
REQUIRE(symtabp != NULL);
symtab = *symtabp;
REQUIRE(VALID_SYMTAB(symtab));
for (i = 0; i < symtab->size; i++) {
for (elt = ISC_LIST_HEAD(symtab->table[i]);
elt != NULL;
elt = nelt) {
nelt = ISC_LIST_NEXT(elt, link);
free_elt(symtab, i, elt);
}
}
free(symtab->table);
symtab->magic = 0;
free(symtab);
*symtabp = NULL;
}
static inline unsigned int
hash(const char *key, isc_boolean_t case_sensitive) {
const char *s;
unsigned int h = 0;
unsigned int g;
int c;
/*
* P. J. Weinberger's hash function, adapted from p. 436 of
* _Compilers: Principles, Techniques, and Tools_, Aho, Sethi
* and Ullman, Addison-Wesley, 1986, ISBN 0-201-10088-6.
*/
if (case_sensitive) {
for (s = key; *s != '\0'; s++) {
h = ( h << 4 ) + *s;
if ((g = ( h & 0xf0000000 )) != 0) {
h = h ^ (g >> 24);
h = h ^ g;
}
}
} else {
for (s = key; *s != '\0'; s++) {
c = *s;
c = tolower((unsigned char)c);
h = ( h << 4 ) + c;
if ((g = ( h & 0xf0000000 )) != 0) {
h = h ^ (g >> 24);
h = h ^ g;
}
}
}
return (h);
}
#define FIND(s, k, t, b, e) \
b = hash((k), (s)->case_sensitive) % (s)->size; \
if ((s)->case_sensitive) { \
for (e = ISC_LIST_HEAD((s)->table[b]); \
e != NULL; \
e = ISC_LIST_NEXT(e, link)) { \
if (((t) == 0 || e->type == (t)) && \
strcmp(e->key, (k)) == 0) \
break; \
} \
} else { \
for (e = ISC_LIST_HEAD((s)->table[b]); \
e != NULL; \
e = ISC_LIST_NEXT(e, link)) { \
if (((t) == 0 || e->type == (t)) && \
strcasecmp(e->key, (k)) == 0) \
break; \
} \
}
isc_result_t
isccc_symtab_lookup(isccc_symtab_t *symtab, const char *key, unsigned int type,
isccc_symvalue_t *value)
{
unsigned int bucket;
elt_t *elt;
REQUIRE(VALID_SYMTAB(symtab));
REQUIRE(key != NULL);
FIND(symtab, key, type, bucket, elt);
if (elt == NULL)
return (ISC_R_NOTFOUND);
if (value != NULL)
*value = elt->value;
return (ISC_R_SUCCESS);
}
isc_result_t
isccc_symtab_define(isccc_symtab_t *symtab, char *key, unsigned int type,
isccc_symvalue_t value, isccc_symexists_t exists_policy)
{
unsigned int bucket;
elt_t *elt;
REQUIRE(VALID_SYMTAB(symtab));
REQUIRE(key != NULL);
REQUIRE(type != 0);
FIND(symtab, key, type, bucket, elt);
if (exists_policy != isccc_symexists_add && elt != NULL) {
if (exists_policy == isccc_symexists_reject)
return (ISC_R_EXISTS);
INSIST(exists_policy == isccc_symexists_replace);
ISC_LIST_UNLINK(symtab->table[bucket], elt, link);
if (symtab->undefine_action != NULL)
(symtab->undefine_action)(elt->key, elt->type,
elt->value,
symtab->undefine_arg);
} else {
elt = malloc(sizeof(*elt));
if (elt == NULL)
return (ISC_R_NOMEMORY);
ISC_LINK_INIT(elt, link);
}
elt->key = key;
elt->type = type;
elt->value = value;
/*
* We prepend so that the most recent definition will be found.
*/
ISC_LIST_PREPEND(symtab->table[bucket], elt, link);
return (ISC_R_SUCCESS);
}
isc_result_t
isccc_symtab_undefine(isccc_symtab_t *symtab, const char *key, unsigned int type) {
unsigned int bucket;
elt_t *elt;
REQUIRE(VALID_SYMTAB(symtab));
REQUIRE(key != NULL);
FIND(symtab, key, type, bucket, elt);
if (elt == NULL)
return (ISC_R_NOTFOUND);
free_elt(symtab, bucket, elt);
return (ISC_R_SUCCESS);
}
void
isccc_symtab_foreach(isccc_symtab_t *symtab, isccc_symtabforeachaction_t action,
void *arg)
{
unsigned int i;
elt_t *elt, *nelt;
REQUIRE(VALID_SYMTAB(symtab));
REQUIRE(action != NULL);
for (i = 0; i < symtab->size; i++) {
for (elt = ISC_LIST_HEAD(symtab->table[i]);
elt != NULL;
elt = nelt) {
nelt = ISC_LIST_NEXT(elt, link);
if ((action)(elt->key, elt->type, elt->value, arg))
free_elt(symtab, i, elt);
}
}
}