/* Copyright (C) 2000, 2001, 2002, 2005 Red Hat, Inc.
This file is part of Red Hat elfutils.
Written by Ulrich Drepper <drepper@redhat.com>, 2000.
Red Hat elfutils is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by the
Free Software Foundation; version 2 of the License.
Red Hat elfutils is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License along
with Red Hat elfutils; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
In addition, as a special exception, Red Hat, Inc. gives You the
additional right to link the code of Red Hat elfutils with code licensed
under any Open Source Initiative certified open source license
(http://www.opensource.org/licenses/index.php) which requires the
distribution of source code with any binary distribution and to
distribute linked combinations of the two. Non-GPL Code permitted under
this exception must only link to the code of Red Hat elfutils through
those well defined interfaces identified in the file named EXCEPTION
found in the source code files (the "Approved Interfaces"). The files
of Non-GPL Code may instantiate templates or use macros or inline
functions from the Approved Interfaces without causing the resulting
work to be covered by the GNU General Public License. Only Red Hat,
Inc. may make changes or additions to the list of Approved Interfaces.
Red Hat's grant of this exception is conditioned upon your not adding
any new exceptions. If you wish to add a new Approved Interface or
exception, please contact Red Hat. You must obey the GNU General Public
License in all respects for all of the Red Hat elfutils code and other
code used in conjunction with Red Hat elfutils except the Non-GPL Code
covered by this exception. If you modify this file, you may extend this
exception to your version of the file, but you are not obligated to do
so. If you do not wish to provide this exception without modification,
you must delete this exception statement from your version and license
this file solely under the GPL without exception.
Red Hat elfutils is an included package of the Open Invention Network.
An included package of the Open Invention Network is a package for which
Open Invention Network licensees cross-license their patents. No patent
license is granted, either expressly or impliedly, by designation as an
included package. Should you wish to participate in the Open Invention
Network licensing program, please visit www.openinventionnetwork.com
<http://www.openinventionnetwork.com>. */
#include <assert.h>
#include <stdlib.h>
#include <system.h>
/* Before including this file the following macros must be defined:
NAME name of the hash table structure.
TYPE data type of the hash table entries
COMPARE comparison function taking two pointers to TYPE objects
The following macros if present select features:
ITERATE iterating over the table entries is possible
REVERSE iterate in reverse order of insert
*/
static size_t
lookup (htab, hval, val)
NAME *htab;
unsigned long int hval;
TYPE val __attribute__ ((unused));
{
/* First hash function: simply take the modul but prevent zero. */
size_t idx = 1 + hval % htab->size;
if (htab->table[idx].hashval != 0)
{
unsigned long int hash;
if (htab->table[idx].hashval == hval
&& COMPARE (htab->table[idx].data, val) == 0)
return idx;
/* Second hash function as suggested in [Knuth]. */
hash = 1 + hval % (htab->size - 2);
do
{
if (idx <= hash)
idx = htab->size + idx - hash;
else
idx -= hash;
/* If entry is found use it. */
if (htab->table[idx].hashval == hval
&& COMPARE (htab->table[idx].data, val) == 0)
return idx;
}
while (htab->table[idx].hashval);
}
return idx;
}
static void
insert_entry_2 (NAME *htab, unsigned long int hval, size_t idx, TYPE data)
{
#ifdef ITERATE
if (htab->table[idx].hashval == 0)
{
# ifdef REVERSE
htab->table[idx].next = htab->first;
htab->first = &htab->table[idx];
# else
/* Add the new value to the list. */
if (htab->first == NULL)
htab->first = htab->table[idx].next = &htab->table[idx];
else
{
htab->table[idx].next = htab->first->next;
htab->first = htab->first->next = &htab->table[idx];
}
# endif
}
#endif
htab->table[idx].hashval = hval;
htab->table[idx].data = data;
++htab->filled;
if (100 * htab->filled > 90 * htab->size)
{
/* Table is filled more than 90%. Resize the table. */
#ifdef ITERATE
__typeof__ (htab->first) first;
# ifndef REVERSE
__typeof__ (htab->first) runp;
# endif
#else
unsigned long int old_size = htab->size;
#endif
#define _TABLE(name) \
name##_ent *table = htab->table
#define TABLE(name) _TABLE (name)
TABLE(NAME);
htab->size = next_prime (htab->size * 2);
htab->filled = 0;
#ifdef ITERATE
first = htab->first;
htab->first = NULL;
#endif
htab->table = calloc ((1 + htab->size), sizeof (htab->table[0]));
if (htab->table == NULL)
{
/* We cannot enlarge the table. Live with what we got. This
might lead to an infinite loop at some point, though. */
htab->table = table;
return;
}
/* Add the old entries to the new table. When iteration is
supported we maintain the order. */
#ifdef ITERATE
# ifdef REVERSE
while (first != NULL)
{
insert_entry_2 (htab, first->hashval,
lookup (htab, first->hashval, first->data),
first->data);
first = first->next;
}
# else
assert (first != NULL);
runp = first = first->next;
do
insert_entry_2 (htab, runp->hashval,
lookup (htab, runp->hashval, runp->data), runp->data);
while ((runp = runp->next) != first);
# endif
#else
for (idx = 1; idx <= old_size; ++idx)
if (table[idx].hashval != 0)
insert_entry_2 (htab, table[idx].hashval,
lookup (htab, table[idx].hashval, table[idx].data),
table[idx].data);
#endif
free (table);
}
}
int
#define INIT(name) _INIT (name)
#define _INIT(name) \
name##_init
INIT(NAME) (htab, init_size)
NAME *htab;
unsigned long int init_size;
{
/* We need the size to be a prime. */
init_size = next_prime (init_size);
/* Initialize the data structure. */
htab->size = init_size;
htab->filled = 0;
#ifdef ITERATE
htab->first = NULL;
#endif
htab->table = (void *) calloc ((init_size + 1), sizeof (htab->table[0]));
if (htab->table == NULL)
return -1;
return 0;
}
int
#define FREE(name) _FREE (name)
#define _FREE(name) \
name##_free
FREE(NAME) (htab)
NAME *htab;
{
free (htab->table);
return 0;
}
int
#define INSERT(name) _INSERT (name)
#define _INSERT(name) \
name##_insert
INSERT(NAME) (htab, hval, data)
NAME *htab;
unsigned long int hval;
TYPE data;
{
size_t idx;
/* Make the hash value nonzero. */
hval = hval ?: 1;
idx = lookup (htab, hval, data);
if (htab->table[idx].hashval != 0)
/* We don't want to overwrite the old value. */
return -1;
/* An empty bucket has been found. */
insert_entry_2 (htab, hval, idx, data);
return 0;
}
#ifdef OVERWRITE
int
#define INSERT(name) _INSERT (name)
#define _INSERT(name) \
name##_overwrite
INSERT(NAME) (htab, hval, data)
NAME *htab;
unsigned long int hval;
TYPE data;
{
size_t idx;
/* Make the hash value nonzero. */
hval = hval ?: 1;
idx = lookup (htab, hval, data);
/* The correct bucket has been found. */
insert_entry_2 (htab, hval, idx, data);
return 0;
}
#endif
TYPE
#define FIND(name) _FIND (name)
#define _FIND(name) \
name##_find
FIND(NAME) (htab, hval, val)
NAME *htab;
unsigned long int hval;
TYPE val;
{
size_t idx;
/* Make the hash value nonzero. */
hval = hval ?: 1;
idx = lookup (htab, hval, val);
if (htab->table[idx].hashval == 0)
return NULL;
return htab->table[idx].data;
}
#ifdef ITERATE
# define ITERATEFCT(name) _ITERATEFCT (name)
# define _ITERATEFCT(name) \
name##_iterate
TYPE
ITERATEFCT(NAME) (htab, ptr)
NAME *htab;
void **ptr;
{
void *p = *ptr;
# define TYPENAME(name) _TYPENAME (name)
# define _TYPENAME(name) name##_ent
# ifdef REVERSE
if (p == NULL)
p = htab->first;
else
p = ((TYPENAME(NAME) *) p)->next;
if (p == NULL)
{
*ptr = NULL;
return NULL;
}
# else
if (p == NULL)
{
if (htab->first == NULL)
return NULL;
p = htab->first->next;
}
else
{
if (p == htab->first)
return NULL;
p = ((TYPENAME(NAME) *) p)->next;
}
# endif
/* Prepare the next element. If possible this will pull the data
into the cache, for reading. */
__builtin_prefetch (((TYPENAME(NAME) *) p)->next, 0, 2);
return ((TYPENAME(NAME) *) (*ptr = p))->data;
}
#endif