mirror of
https://github.com/UberGames/RPG-X2.git
synced 2024-11-26 14:21:08 +00:00
141 lines
3.6 KiB
C
141 lines
3.6 KiB
C
/* Copyright (C) 2005 MySQL AB
|
|
|
|
This program 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.
|
|
|
|
This program 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 this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
|
|
|
|
#ifndef _trie_h
|
|
#define _trie_h
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
typedef struct st_trie_node
|
|
{
|
|
uint16 leaf; /* Depth from root node if match, 0 else */
|
|
uchar c; /* Label on this edge */
|
|
struct st_trie_node *next; /* Next label */
|
|
struct st_trie_node *links; /* Array of edges leaving this node */
|
|
struct st_trie_node *fail; /* AC failure function */
|
|
} TRIE_NODE;
|
|
|
|
typedef struct st_trie
|
|
{
|
|
TRIE_NODE root;
|
|
MEM_ROOT mem_root;
|
|
CHARSET_INFO *charset;
|
|
uint32 nnodes;
|
|
uint32 nwords;
|
|
} TRIE;
|
|
|
|
typedef struct st_ac_trie_state
|
|
{
|
|
TRIE *trie;
|
|
TRIE_NODE *node;
|
|
} AC_TRIE_STATE;
|
|
|
|
extern TRIE *trie_init (TRIE *trie, CHARSET_INFO *charset);
|
|
extern void trie_free (TRIE *trie);
|
|
extern my_bool trie_insert (TRIE *trie, const uchar *key, uint keylen);
|
|
extern my_bool ac_trie_prepare (TRIE *trie);
|
|
extern void ac_trie_init (TRIE *trie, AC_TRIE_STATE *state);
|
|
|
|
|
|
/* `trie_goto' is internal function and shouldn't be used. */
|
|
|
|
static inline TRIE_NODE *trie_goto (TRIE_NODE *root, TRIE_NODE *node, uchar c)
|
|
{
|
|
TRIE_NODE *next;
|
|
DBUG_ENTER("trie_goto");
|
|
for (next= node->links; next; next= next->next)
|
|
if (next->c == c)
|
|
DBUG_RETURN(next);
|
|
if (root == node)
|
|
DBUG_RETURN(root);
|
|
DBUG_RETURN(NULL);
|
|
}
|
|
|
|
|
|
/*
|
|
SYNOPSIS
|
|
int ac_trie_next (AC_TRIE_STATE *state, uchar *c);
|
|
state - valid pointer to `AC_TRIE_STATE'
|
|
c - character to lookup
|
|
|
|
DESCRIPTION
|
|
Implementation of search using Aho-Corasick automaton.
|
|
Performs char-by-char search.
|
|
|
|
RETURN VALUE
|
|
`ac_trie_next' returns length of matched word or 0.
|
|
*/
|
|
|
|
static inline int ac_trie_next (AC_TRIE_STATE *state, uchar *c)
|
|
{
|
|
TRIE_NODE *root, *node;
|
|
DBUG_ENTER("ac_trie_next");
|
|
DBUG_ASSERT(state && c);
|
|
root= &state->trie->root;
|
|
node= state->node;
|
|
while (! (state->node= trie_goto(root, node, *c)))
|
|
node= node->fail;
|
|
DBUG_RETURN(state->node->leaf);
|
|
}
|
|
|
|
|
|
/*
|
|
SYNOPSIS
|
|
my_bool trie_search (TRIE *trie, const uchar *key, uint keylen);
|
|
trie - valid pointer to `TRIE'
|
|
key - valid pointer to key to insert
|
|
keylen - non-0 key length
|
|
|
|
DESCRIPTION
|
|
Performs key lookup in trie.
|
|
|
|
RETURN VALUE
|
|
`trie_search' returns `true' if key is in `trie'. Otherwise,
|
|
`false' is returned.
|
|
|
|
NOTES
|
|
Consecutive search here is "best by test". arrays are very short, so
|
|
binary search or hashing would add too much complexity that would
|
|
overweight speed gain. Especially because compiler can optimize simple
|
|
consecutive loop better (tested)
|
|
*/
|
|
|
|
static inline my_bool trie_search (TRIE *trie, const uchar *key, uint keylen)
|
|
{
|
|
TRIE_NODE *node;
|
|
uint k;
|
|
DBUG_ENTER("trie_search");
|
|
DBUG_ASSERT(trie && key && keylen);
|
|
node= &trie->root;
|
|
|
|
for (k= 0; k < keylen; k++)
|
|
{
|
|
uchar p;
|
|
if (! (node= node->links))
|
|
DBUG_RETURN(FALSE);
|
|
p= key[k];
|
|
while (p != node->c)
|
|
if (! (node= node->next))
|
|
DBUG_RETURN(FALSE);
|
|
}
|
|
|
|
DBUG_RETURN(node->leaf > 0);
|
|
}
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif
|