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/*
* Copyright (c) 2002-2005 The TenDRA Project <http://www.tendra.org/>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of The TenDRA Project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific, prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
* IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id$
*/
/*
Crown Copyright (c) 1997
This TenDRA(r) Computer Program is subject to Copyright
owned by the United Kingdom Secretary of State for Defence
acting through the Defence Evaluation and Research Agency
(DERA). It is made available to Recipients with a
royalty-free licence for its use, reproduction, transfer
to other parties and amendment for any purpose not excluding
product development provided that any such use et cetera
shall be deemed to be acceptance of the following conditions:-
(1) Its Recipients shall ensure that this Notice is
reproduced upon any copies or amended versions of it;
(2) Any amended version of it shall be clearly marked to
show both the nature of and the organisation responsible
for the relevant amendment or amendments;
(3) Its onward transfer from a recipient to another
party shall be deemed to be that party's acceptance of
these conditions;
(4) DERA gives no warranty or assurance as to its
quality or suitability for any purpose and DERA accepts
no liability whatsoever in relation to any use to which
it may be put.
*/
#include "config.h"
#include "object.h"
#include "hash.h"
#include "type.h"
#include "utility.h"
/*
STANDARD HASH TABLES
These hash tables represent the various namespaces permitted in C
plus the TDF token namespace.
*/
hash_table *exps;
hash_table *files;
hash_table *keywords;
hash_table *subsets;
hash_table *tags;
hash_table *tag_fields;
hash_table *tokens;
hash_table *types;
hash_table *type_fields;
/*
INITIALISATION ROUTINE
This routine initialises the standard hash tables and sets a few
miscellaneous variables.
*/
void
init_hash(void)
{
buffer = alloc_nof(char, buffsize + 100);
exps = make_hash_table("Expression");
files = make_hash_table("Output file");
keywords = make_hash_table("Keyword");
subsets = make_hash_table("Set");
tags = make_hash_table("Tag");
tag_fields = make_hash_table("Field selector struct/union");
tokens = make_hash_table("Token");
types = make_hash_table("Type");
type_fields = make_hash_table("Field selector");
return;
}
/*
HASHING ROUTINE
This routine finds the hash value of the string nm. This value must
lie in the range [ 0, hash_size ).
*/
static int
hash(char *nm)
{
char *s;
int n = 0;
for (s = nm; *s; s++)n += *s;
return(n % hash_size);
}
/*
CREATE A NEW HASH TABLE
This routine creates a new hash table called nm.
*/
hash_table *
make_hash_table(char *nm)
{
int i;
hash_table *t = alloc_nof(hash_table, 1);
t->name = nm;
for (i = 0; i < hash_size; i++)t->array [i] = null;
return(t);
}
/*
LOOK UP A NAME IN A HASH TABLE
This routine looks up the object nm (version v) in the hth column
of hash table t. It returns the object if it is found, or null
otherwise.
*/
static object *
lookup_hash(hash_table *t, char *nm, int v, int h)
{
hash_elem *e = t->array [h];
while (e) {
if (streq(nm, e->obj->name)) {
if (v == e->vers || v == any_version) return(e->obj);
}
e = e->next;
}
return(null);
}
/*
ADD AN OBJECT TO A HASH TABLE
This routine adds the object p (version v) to the hash table t,
reporting an error and returning the old value if it is already
defined. Otherwise it returns p.
*/
object *
add_hash(hash_table *t, object *p, int v)
{
hash_elem *e;
char *nm = p->name;
int h = hash(nm);
object *q = lookup_hash(t, nm, v, h);
if (q != null) {
char *fn = q->filename;
if (fn) {
char *err = "%s '%s' already defined (%s, line %d)";
error(ERR_SERIOUS, err, t->name, nm, fn, q->line_no);
} else {
error(ERR_SERIOUS, "%s '%s' already defined", t->name, nm);
}
return(q);
}
alloc_variable(e, hash_elem, 1000);
e->obj = p;
e->vers = v;
e->next = t->array [h];
t->array [h] = e;
return(p);
}
/*
SEARCH A HASH TABLE FOR AN OBJECT
This routine searches the hash table t for the object named nm
(version v), returning it if it is found. If it is not found then
null is returned.
*/
object *
search_hash(hash_table *t, char *nm, int v)
{
int h = hash(nm);
return(lookup_hash(t, nm, v, h));
}
/*
SORT THE ELEMENTS OF A HASH LIST
This routine sorts the elements of the hash table t into a single
alphabetical list. The table cannot be used subsequently.
*/
hash_elem *
sort_hash(hash_table *t)
{
int i;
hash_elem *r = null;
for (i = 0; i < hash_size; i++) {
hash_elem *p = t->array [i] ;
while (p) {
hash_elem *pn = p->next;
hash_elem *q = r, *s = null;
while (q) {
if (strcmp(p->obj->name, q->obj->name) <= 0)break;
s = q;
q = q->next;
}
if (s == null) {
p->next = r;
r = p;
} else {
p->next = s->next;
s->next = p;
}
p = pn;
}
}
return(r);
}