qse/ase/cmn/map.c
2008-02-14 20:38:18 +00:00

399 lines
7.4 KiB
C

/*
* $Id: map.c,v 1.11 2007/11/10 15:21:40 bacon Exp $
*
* {License}
*/
#include <ase/cmn/map.h>
#include <ase/cmn/str.h>
static ase_size_t hashkey (const ase_char_t* keyptr, ase_size_t keylen);
static int rehash (ase_map_t* map);
#define FREE_PAIR(map,pair) \
do { \
if ((map)->freeval != ASE_NULL) \
(map)->freeval ((map)->owner, ASE_PAIR_VAL(pair)); \
ASE_FREE ((map)->mmgr, pair); \
} while (0)
ase_map_t* ase_map_open (
void* owner, ase_size_t capa, unsigned int factor,
void(*freeval)(void*,void*), void(*sameval)(void*,void*),
ase_mmgr_t* mmgr)
{
ase_map_t* map;
ASE_ASSERTX (capa > 0, "the initial capacity should be greater than 0");
map = (ase_map_t*) ASE_MALLOC (mmgr, ASE_SIZEOF(ase_map_t));
if (map == ASE_NULL) return ASE_NULL;
map->mmgr = mmgr;
map->buck = (ase_pair_t**)
ASE_MALLOC (mmgr, ASE_SIZEOF(ase_pair_t*)*capa);
if (map->buck == ASE_NULL)
{
ASE_FREE (mmgr, map);
return ASE_NULL;
}
map->owner = owner;
map->capa = capa;
map->size = 0;
map->freeval = freeval;
map->sameval = sameval;
while (capa > 0) map->buck[--capa] = ASE_NULL;
map->factor = factor;
map->threshold = ((ase_size_t)map->factor) * map->capa / 100;
return map;
}
void ase_map_close (ase_map_t* map)
{
ase_map_clear (map);
ASE_FREE (map->mmgr, map->buck);
ASE_FREE (map->mmgr, map);
}
void ase_map_clear (ase_map_t* map)
{
ase_size_t i;
ase_pair_t* pair, * next;
for (i = 0; i < map->capa; i++)
{
pair = map->buck[i];
while (pair != ASE_NULL)
{
next = ASE_PAIR_LNK(pair);
FREE_PAIR (map, pair);
map->size--;
pair = next;
}
map->buck[i] = ASE_NULL;
}
}
ase_size_t ase_map_getsize (ase_map_t* map)
{
return map->size;
}
ase_pair_t* ase_map_get (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen)
{
ase_pair_t* pair;
ase_size_t hc;
hc = hashkey(keyptr,keylen) % map->capa;
pair = map->buck[hc];
while (pair != ASE_NULL)
{
if (ase_strxncmp (
ASE_PAIR_KEYPTR(pair), ASE_PAIR_KEYLEN(pair),
keyptr, keylen) == 0) return pair;
pair = ASE_PAIR_LNK(pair);
}
return ASE_NULL;
}
ase_pair_t* ase_map_put (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen,
void* val)
{
int n;
ase_pair_t* px;
n = ase_map_putx (map, keyptr, keylen, val, &px);
if (n < 0) return ASE_NULL;
return px;
}
int ase_map_putx (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen,
void* val, ase_pair_t** px)
{
ase_pair_t* pair;
ase_size_t hc;
hc = hashkey(keyptr,keylen) % map->capa;
pair = map->buck[hc];
while (pair != ASE_NULL)
{
if (ase_strxncmp (
ASE_PAIR_KEYPTR(pair), ASE_PAIR_KEYLEN(pair),
keyptr, keylen) == 0)
{
if (px != ASE_NULL)
*px = ase_map_setpair (map, pair, val);
else
ase_map_setpair (map, pair, val);
return 0; /* value changed for the existing key */
}
pair = ASE_PAIR_LNK(pair);
}
if (map->threshold > 0 &&
map->size >= map->threshold)
{
if (rehash(map) == 0) /* ignore the rehash error */
{
hc = hashkey(keyptr,keylen) % map->capa;
}
}
pair = (ase_pair_t*) ASE_MALLOC (map->mmgr,
ASE_SIZEOF(ase_pair_t) + ((keylen+1)*ASE_SIZEOF(*keyptr)));
if (pair == ASE_NULL) return -1; /* error */
/* duplicate the key if it is new */
ASE_PAIR_KEYPTR(pair) = (ase_char_t*)(pair + 1);
ase_strncpy (ASE_PAIR_KEYPTR(pair), keyptr, keylen);
ASE_PAIR_KEYLEN(pair) = keylen;
ASE_PAIR_VAL(pair) = val;
ASE_PAIR_LNK(pair) = map->buck[hc];
map->buck[hc] = pair;
map->size++;
if (px != ASE_NULL) *px = pair;
return 1; /* new key added */
}
ase_pair_t* ase_map_set (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen,
void* val)
{
ase_pair_t* pair;
ase_size_t hc;
hc = hashkey(keyptr,keylen) % map->capa;
pair = map->buck[hc];
while (pair != ASE_NULL)
{
if (ase_strxncmp (
ASE_PAIR_KEYPTR(pair), ASE_PAIR_KEYLEN(pair),
keyptr, keylen) == 0)
{
return ase_map_setpair (map, pair, val);
}
pair = ASE_PAIR_LNK(pair);
}
return ASE_NULL;
}
ase_pair_t* ase_map_getpair (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen,
void** val)
{
ase_pair_t* pair;
pair = ase_map_get (map, keyptr, keylen);
if (pair == ASE_NULL) return ASE_NULL;
*val = ASE_PAIR_VAL(pair);
return pair;
}
ase_pair_t* ase_map_setpair (
ase_map_t* map, ase_pair_t* pair, void* val)
{
/* use this function with care */
if (ASE_PAIR_VAL(pair) == val)
{
/* if the old value and the new value are the same,
* it just calls the handler for this condition.
* No value replacement occurs. */
if (map->sameval != ASE_NULL)
{
map->sameval (map->owner, val);
}
}
else
{
/* frees the old value */
if (map->freeval != ASE_NULL)
{
map->freeval (map->owner, ASE_PAIR_VAL(pair));
}
/* the new value takes the place */
ASE_PAIR_VAL(pair) = val;
}
return pair;
}
int ase_map_remove (
ase_map_t* map, const ase_char_t* keyptr, ase_size_t keylen)
{
ase_pair_t* pair, * prev;
ase_size_t hc;
hc = hashkey(keyptr,keylen) % map->capa;
pair = map->buck[hc];
prev = ASE_NULL;
while (pair != ASE_NULL)
{
if (ase_strxncmp (
ASE_PAIR_KEYPTR(pair), ASE_PAIR_KEYLEN(pair),
keyptr, keylen) == 0)
{
if (prev == ASE_NULL)
map->buck[hc] = ASE_PAIR_LNK(pair);
else prev->next = ASE_PAIR_LNK(pair);
FREE_PAIR (map, pair);
map->size--;
return 0;
}
prev = pair;
pair = ASE_PAIR_LNK(pair);
}
return -1;
}
int ase_map_walk (ase_map_t* map,
int (*walker) (ase_pair_t*,void*), void* arg)
{
ase_size_t i;
ase_pair_t* pair, * next;
for (i = 0; i < map->capa; i++)
{
pair = map->buck[i];
while (pair != ASE_NULL)
{
next = ASE_PAIR_LNK(pair);
if (walker(pair,arg) == -1) return -1;
pair = next;
}
}
return 0;
}
ase_pair_t* ase_map_getfirstpair (
ase_map_t* map, ase_size_t* buckno)
{
ase_size_t i;
ase_pair_t* pair;
for (i = 0; i < map->capa; i++)
{
pair = map->buck[i];
if (pair != ASE_NULL)
{
*buckno = i;
return pair;
}
}
return ASE_NULL;
}
ase_pair_t* ase_map_getnextpair (
ase_map_t* map, ase_pair_t* pair, ase_size_t* buckno)
{
ase_size_t i;
ase_pair_t* next;
next = ASE_PAIR_LNK(pair);
if (next != ASE_NULL)
{
/* no change in bucket number */
return next;
}
for (i = (*buckno)+1; i < map->capa; i++)
{
pair = map->buck[i];
if (pair != ASE_NULL)
{
*buckno = i;
return pair;
}
}
return ASE_NULL;
}
static ase_size_t hashkey (const ase_char_t* keyptr, ase_size_t keylen)
{
ase_size_t n = 0, i;
const ase_char_t* end = keyptr + keylen;
while (keyptr < end)
{
ase_byte_t* bp = (ase_byte_t*)keyptr;
for (i = 0; i < ASE_SIZEOF(*keyptr); i++) n = n * 31 + *bp++;
keyptr++;
}
return n;
}
static int rehash (ase_map_t* map)
{
ase_size_t i, hc, new_capa;
ase_pair_t** new_buck;
new_capa = (map->capa >= 65536)? (map->capa + 65536): (map->capa << 1);
new_buck = (ase_pair_t**) ASE_MALLOC (
map->mmgr, ASE_SIZEOF(ase_pair_t*) * new_capa);
if (new_buck == ASE_NULL)
{
/* once rehash fails, the rehashing is disabled */
map->threshold = 0;
return -1;
}
for (i = 0; i < new_capa; i++) new_buck[i] = ASE_NULL;
for (i = 0; i < map->capa; i++)
{
ase_pair_t* pair = map->buck[i];
while (pair != ASE_NULL)
{
ase_pair_t* next = ASE_PAIR_LNK(pair);
hc = hashkey(
ASE_PAIR_KEYPTR(pair),
ASE_PAIR_KEYLEN(pair)) % new_capa;
ASE_PAIR_LNK(pair) = new_buck[hc];
new_buck[hc] = pair;
pair = next;
}
}
ASE_FREE (map->mmgr, map->buck);
map->buck = new_buck;
map->capa = new_capa;
map->threshold = ((ase_size_t)map->factor) * map->capa / 100;
return 0;
}