tesseract/wordrec/closed.cpp
2007-03-07 20:03:40 +00:00

137 lines
4.1 KiB
C++

/* -*-C-*-
********************************************************************************
*
* File: closed.c (Formerly closed.c)
* Description: Hash table for closed search states.
* Author: Mark Seaman, OCR Technology
* Created: Fri Oct 16 14:37:00 1987
* Modified: Fri May 25 11:31:16 1990 (Mark Seaman) marks@hpgrlt
* Language: C
* Package: N/A
* Status: Reusable Software Component
*
* (c) Copyright 1987, Hewlett-Packard Company.
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
** http://www.apache.org/licenses/LICENSE-2.0
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*
*********************************************************************************/
/*----------------------------------------------------------------------
I n c l u d e s
----------------------------------------------------------------------*/
#include "freelist.h"
#include "closed.h"
#include "cutil.h"
#include "callcpp.h"
//#include <process.h>
#ifdef __UNIX__
#include <assert.h>
#endif
/*----------------------------------------------------------------------
V a r i a b l e s
----------------------------------------------------------------------*/
#define TABLE_SIZE 2000
HASH_TABLE global_hash = NULL;
/*----------------------------------------------------------------------
F u n c t i o n s
----------------------------------------------------------------------*/
/**********************************************************************
* hash_add
*
* Look in the hash table for a particular value. If it is not there
* then add it.
**********************************************************************/
int hash_add(HASH_TABLE state_table, STATE *state) {
int x;
int i = 0;
int table_limit = TABLE_SIZE;
x = state->part2 % table_limit;
while (i < table_limit) {
assert (0 <= x && x < table_limit);
/* Found it */
if ((state_table[x].part2 == state->part2) &&
(state_table[x].part1 == state->part1)) {
return (FALSE);
}
/* Not in table */
else if (state_table[x].part1 == NO_STATE) {
state_table[x].part2 = state->part2;
state_table[x].part1 = state->part1;
return (TRUE);
}
i++;
if (++x >= table_limit)
x = 0;
}
cprintf("warning: hash table is full");
abort();
return 0;
}
/**********************************************************************
* hash_lookup
*
* Look in the hash table for a particular value. If the value is there
* then return TRUE, FALSE otherwise.
**********************************************************************/
int hash_lookup(HASH_TABLE state_table, STATE *state) {
int x;
int i = 0;
int table_limit = TABLE_SIZE;
x = state->part2 % table_limit;
while (i < table_limit) {
assert (0 <= x && x < table_limit);
/* Found it */
if ((state_table[x].part2 == state->part2) &&
(state_table[x].part1 == state->part1)) {
return (TRUE);
}
/* Not in table */
else if (state_table[x].part1 == NO_STATE) {
return (FALSE);
}
i++;
if (++x >= table_limit)
x = 0;
}
cprintf ("warning: fell off end of hash table (%x) %x\n",
state->part2, state->part2 % table_limit);
abort();
return 0;
}
/**********************************************************************
* new_hash_table
*
* Create and initialize a hash table.
**********************************************************************/
HASH_TABLE new_hash_table() {
HASH_TABLE ht;
int x;
if (global_hash == NULL)
ht = (HASH_TABLE) memalloc (TABLE_SIZE * sizeof (STATE));
else
ht = global_hash;
for (x = 0; x < TABLE_SIZE; x++) {
ht[x].part1 = NO_STATE;
ht[x].part2 = NO_STATE;
}
return (ht);
}