postgresql/contrib/btree_gist/btree_utils_var.c
2009-06-11 14:49:15 +00:00

600 lines
13 KiB
C

/*
* $PostgreSQL: pgsql/contrib/btree_gist/btree_utils_var.c,v 1.21 2009/06/11 14:48:50 momjian Exp $
*/
#include "btree_gist.h"
#include <math.h>
#include <limits.h>
#include <float.h>
#include "btree_utils_var.h"
#include "utils/pg_locale.h"
#include "utils/builtins.h"
#include "utils/rel.h"
PG_FUNCTION_INFO_V1(gbt_var_decompress);
Datum gbt_var_decompress(PG_FUNCTION_ARGS);
Datum
gbt_var_decompress(PG_FUNCTION_ARGS)
{
GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
GBT_VARKEY *key = (GBT_VARKEY *) DatumGetPointer(PG_DETOAST_DATUM(entry->key));
if (key != (GBT_VARKEY *) DatumGetPointer(entry->key))
{
GISTENTRY *retval = (GISTENTRY *) palloc(sizeof(GISTENTRY));
gistentryinit(*retval, PointerGetDatum(key),
entry->rel, entry->page,
entry->offset, FALSE);
PG_RETURN_POINTER(retval);
}
PG_RETURN_POINTER(entry);
}
/* Returns a better readable representaion of variable key ( sets pointer ) */
GBT_VARKEY_R
gbt_var_key_readable(const GBT_VARKEY *k)
{
GBT_VARKEY_R r;
r.lower = (bytea *) &(((char *) k)[VARHDRSZ]);
if (VARSIZE(k) > (VARHDRSZ + (VARSIZE(r.lower))))
r.upper = (bytea *) &(((char *) k)[VARHDRSZ + INTALIGN(VARSIZE(r.lower))]);
else
r.upper = r.lower;
return r;
}
GBT_VARKEY *
gbt_var_key_copy(const GBT_VARKEY_R *u, bool force_node)
{
GBT_VARKEY *r = NULL;
if (u->lower == u->upper && !force_node)
{ /* leaf key mode */
r = (GBT_VARKEY *) palloc(VARSIZE(u->lower) + VARHDRSZ);
memcpy(VARDATA(r), u->lower, VARSIZE(u->lower));
SET_VARSIZE(r, VARSIZE(u->lower) + VARHDRSZ);
}
else
{ /* node key mode */
r = (GBT_VARKEY *) palloc(INTALIGN(VARSIZE(u->lower)) + VARSIZE(u->upper) + VARHDRSZ);
memcpy(VARDATA(r), u->lower, VARSIZE(u->lower));
memcpy(VARDATA(r) + INTALIGN(VARSIZE(u->lower)), u->upper, VARSIZE(u->upper));
SET_VARSIZE(r, INTALIGN(VARSIZE(u->lower)) + VARSIZE(u->upper) + VARHDRSZ);
}
return r;
}
static GBT_VARKEY *
gbt_var_leaf2node(GBT_VARKEY *leaf, const gbtree_vinfo *tinfo)
{
GBT_VARKEY *out = leaf;
if (tinfo->f_l2n)
out = (*tinfo->f_l2n) (leaf);
return out;
}
/*
* returns the common prefix length of a node key
*/
static int32
gbt_var_node_cp_len(const GBT_VARKEY *node, const gbtree_vinfo *tinfo)
{
GBT_VARKEY_R r = gbt_var_key_readable(node);
int32 i = 0;
int32 l = 0;
int32 t1len = VARSIZE(r.lower) - VARHDRSZ;
int32 t2len = VARSIZE(r.upper) - VARHDRSZ;
int32 ml = Min(t1len, t2len);
char *p1 = VARDATA(r.lower);
char *p2 = VARDATA(r.upper);
if (ml == 0)
return 0;
while (i < ml)
{
if (tinfo->eml > 1 && l == 0)
{
if ((l = pg_mblen(p1)) != pg_mblen(p2))
{
return i;
}
}
if (*p1 != *p2)
{
if (tinfo->eml > 1)
{
return (i - l + 1);
}
else
{
return i;
}
}
p1++;
p2++;
l--;
i++;
}
return (ml); /* lower == upper */
}
/*
* returns true, if query matches prefix ( common prefix )
*/
static bool
gbt_bytea_pf_match(const bytea *pf, const bytea *query, const gbtree_vinfo *tinfo)
{
bool out = FALSE;
int32 k = 0;
int32 qlen = VARSIZE(query) - VARHDRSZ;
int32 nlen = VARSIZE(pf) - VARHDRSZ;
if (nlen <= qlen)
{
char *q = VARDATA(query);
char *n = VARDATA(pf);
if (tinfo->eml > 1)
{
out = (varstr_cmp(q, nlen, n, nlen) == 0);
}
else
{
out = TRUE;
for (k = 0; k < nlen; k++)
{
if (*n != *q)
{
out = FALSE;
break;
}
if (k < (nlen - 1))
{
q++;
n++;
}
}
}
}
return out;
}
/*
* returns true, if query matches node using common prefix
*/
static bool
gbt_var_node_pf_match(const GBT_VARKEY_R *node, const bytea *query, const gbtree_vinfo *tinfo)
{
return (tinfo->trnc && (
gbt_bytea_pf_match(node->lower, query, tinfo) ||
gbt_bytea_pf_match(node->upper, query, tinfo)
));
}
/*
* truncates / compresses the node key
* cpf_length .. common prefix length
*/
static GBT_VARKEY *
gbt_var_node_truncate(const GBT_VARKEY *node, int32 cpf_length, const gbtree_vinfo *tinfo)
{
GBT_VARKEY *out = NULL;
GBT_VARKEY_R r = gbt_var_key_readable(node);
int32 len1 = VARSIZE(r.lower) - VARHDRSZ;
int32 len2 = VARSIZE(r.upper) - VARHDRSZ;
int32 si;
char *out2;
len1 = Min(len1, (cpf_length + 1));
len2 = Min(len2, (cpf_length + 1));
si = 2 * VARHDRSZ + INTALIGN(len1 + VARHDRSZ) + len2;
out = (GBT_VARKEY *) palloc(si);
SET_VARSIZE(out, si);
memcpy(VARDATA(out), r.lower, len1 + VARHDRSZ);
SET_VARSIZE(VARDATA(out), len1 + VARHDRSZ);
out2 = VARDATA(out) + INTALIGN(len1 + VARHDRSZ);
memcpy(out2, r.upper, len2 + VARHDRSZ);
SET_VARSIZE(out2, len2 + VARHDRSZ);
return out;
}
void
gbt_var_bin_union(Datum *u, GBT_VARKEY *e, const gbtree_vinfo *tinfo)
{
GBT_VARKEY *nk = NULL;
GBT_VARKEY *tmp = NULL;
GBT_VARKEY_R nr;
GBT_VARKEY_R eo = gbt_var_key_readable(e);
if (eo.lower == eo.upper) /* leaf */
{
tmp = gbt_var_leaf2node(e, tinfo);
if (tmp != e)
eo = gbt_var_key_readable(tmp);
}
if (DatumGetPointer(*u))
{
GBT_VARKEY_R ro = gbt_var_key_readable((GBT_VARKEY *) DatumGetPointer(*u));
if ((*tinfo->f_cmp) ((bytea *) ro.lower, (bytea *) eo.lower) > 0)
{
nr.lower = eo.lower;
nr.upper = ro.upper;
nk = gbt_var_key_copy(&nr, TRUE);
}
if ((*tinfo->f_cmp) ((bytea *) ro.upper, (bytea *) eo.upper) < 0)
{
nr.upper = eo.upper;
nr.lower = ro.lower;
nk = gbt_var_key_copy(&nr, TRUE);
}
if (nk)
*u = PointerGetDatum(nk);
}
else
{
nr.lower = eo.lower;
nr.upper = eo.upper;
*u = PointerGetDatum(gbt_var_key_copy(&nr, TRUE));
}
}
GISTENTRY *
gbt_var_compress(GISTENTRY *entry, const gbtree_vinfo *tinfo)
{
GISTENTRY *retval;
if (entry->leafkey)
{
GBT_VARKEY *r = NULL;
bytea *leaf = (bytea *) DatumGetPointer(PG_DETOAST_DATUM(entry->key));
GBT_VARKEY_R u;
u.lower = u.upper = leaf;
r = gbt_var_key_copy(&u, FALSE);
retval = palloc(sizeof(GISTENTRY));
gistentryinit(*retval, PointerGetDatum(r),
entry->rel, entry->page,
entry->offset, TRUE);
}
else
retval = entry;
return (retval);
}
GBT_VARKEY *
gbt_var_union(const GistEntryVector *entryvec, int32 *size, const gbtree_vinfo *tinfo)
{
int i = 0,
numranges = entryvec->n;
GBT_VARKEY *cur;
Datum out;
GBT_VARKEY_R rk;
*size = sizeof(GBT_VARKEY);
cur = (GBT_VARKEY *) DatumGetPointer(entryvec->vector[0].key);
rk = gbt_var_key_readable(cur);
out = PointerGetDatum(gbt_var_key_copy(&rk, TRUE));
for (i = 1; i < numranges; i++)
{
cur = (GBT_VARKEY *) DatumGetPointer(entryvec->vector[i].key);
gbt_var_bin_union(&out, cur, tinfo);
}
/* Truncate (=compress) key */
if (tinfo->trnc)
{
int32 plen;
GBT_VARKEY *trc = NULL;
plen = gbt_var_node_cp_len((GBT_VARKEY *) DatumGetPointer(out), tinfo);
trc = gbt_var_node_truncate((GBT_VARKEY *) DatumGetPointer(out), plen + 1, tinfo);
out = PointerGetDatum(trc);
}
return ((GBT_VARKEY *) DatumGetPointer(out));
}
bool
gbt_var_same(bool *result, const Datum d1, const Datum d2, const gbtree_vinfo *tinfo)
{
GBT_VARKEY *t1 = (GBT_VARKEY *) DatumGetPointer(d1);
GBT_VARKEY *t2 = (GBT_VARKEY *) DatumGetPointer(d2);
GBT_VARKEY_R r1,
r2;
r1 = gbt_var_key_readable(t1);
r2 = gbt_var_key_readable(t2);
if (t1 && t2)
{
*result = (((*tinfo->f_cmp) ((bytea *) r1.lower, (bytea *) r2.lower) == 0
&& (*tinfo->f_cmp) ((bytea *) r1.upper, (bytea *) r2.upper) == 0) ? TRUE : FALSE);
}
else
*result = (t1 == NULL && t2 == NULL) ? TRUE : FALSE;
PG_RETURN_POINTER(result);
}
float *
gbt_var_penalty(float *res, const GISTENTRY *o, const GISTENTRY *n, const gbtree_vinfo *tinfo)
{
GBT_VARKEY *orge = (GBT_VARKEY *) DatumGetPointer(o->key);
GBT_VARKEY *newe = (GBT_VARKEY *) DatumGetPointer(n->key);
GBT_VARKEY_R ok,
nk;
GBT_VARKEY *tmp = NULL;
*res = 0.0;
nk = gbt_var_key_readable(newe);
if (nk.lower == nk.upper) /* leaf */
{
tmp = gbt_var_leaf2node(newe, tinfo);
if (tmp != newe)
nk = gbt_var_key_readable(tmp);
}
ok = gbt_var_key_readable(orge);
if ((VARSIZE(ok.lower) - VARHDRSZ) == 0 && (VARSIZE(ok.upper) - VARHDRSZ) == 0)
*res = 0.0;
else if (!(
(
((*tinfo->f_cmp) (nk.lower, ok.lower) >= 0 || gbt_bytea_pf_match(ok.lower, nk.lower, tinfo)) &&
((*tinfo->f_cmp) (nk.upper, ok.upper) <= 0 || gbt_bytea_pf_match(ok.upper, nk.upper, tinfo))
)
))
{
Datum d = PointerGetDatum(0);
double dres = 0.0;
int32 ol,
ul;
gbt_var_bin_union(&d, orge, tinfo);
ol = gbt_var_node_cp_len((GBT_VARKEY *) DatumGetPointer(d), tinfo);
gbt_var_bin_union(&d, newe, tinfo);
ul = gbt_var_node_cp_len((GBT_VARKEY *) DatumGetPointer(d), tinfo);
if (ul < ol)
{
dres = (ol - ul); /* lost of common prefix len */
}
else
{
GBT_VARKEY_R uk = gbt_var_key_readable((GBT_VARKEY *) DatumGetPointer(d));
char tmp[4];
tmp[0] = ((VARSIZE(ok.lower) - VARHDRSZ) == ul) ? (CHAR_MIN) : (VARDATA(ok.lower)[ul]);
tmp[1] = ((VARSIZE(uk.lower) - VARHDRSZ) == ul) ? (CHAR_MIN) : (VARDATA(uk.lower)[ul]);
tmp[2] = ((VARSIZE(ok.upper) - VARHDRSZ) == ul) ? (CHAR_MIN) : (VARDATA(ok.upper)[ul]);
tmp[3] = ((VARSIZE(uk.upper) - VARHDRSZ) == ul) ? (CHAR_MIN) : (VARDATA(uk.upper)[ul]);
dres = (tmp[0] - tmp[1]) +
(tmp[3] - tmp[2]);
dres /= 256.0;
}
*res += FLT_MIN;
*res += (float) (dres / ((double) (ol + 1)));
*res *= (FLT_MAX / (o->rel->rd_att->natts + 1));
}
return res;
}
static int
gbt_vsrt_cmp(const void *a, const void *b, void *arg)
{
GBT_VARKEY_R ar = gbt_var_key_readable(((const Vsrt *) a)->t);
GBT_VARKEY_R br = gbt_var_key_readable(((const Vsrt *) b)->t);
const gbtree_vinfo *tinfo = (const gbtree_vinfo *) arg;
return (*tinfo->f_cmp) (ar.lower, br.lower);
}
GIST_SPLITVEC *
gbt_var_picksplit(const GistEntryVector *entryvec, GIST_SPLITVEC *v, const gbtree_vinfo *tinfo)
{
OffsetNumber i,
maxoff = entryvec->n - 1;
Vsrt *arr;
int svcntr = 0,
nbytes;
char *cur;
GBT_VARKEY **sv = NULL;
arr = (Vsrt *) palloc((maxoff + 1) * sizeof(Vsrt));
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
v->spl_left = (OffsetNumber *) palloc(nbytes);
v->spl_right = (OffsetNumber *) palloc(nbytes);
v->spl_ldatum = PointerGetDatum(0);
v->spl_rdatum = PointerGetDatum(0);
v->spl_nleft = 0;
v->spl_nright = 0;
sv = palloc(sizeof(bytea *) * (maxoff + 1));
/* Sort entries */
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
{
GBT_VARKEY_R ro;
cur = (char *) DatumGetPointer(entryvec->vector[i].key);
ro = gbt_var_key_readable((GBT_VARKEY *) cur);
if (ro.lower == ro.upper) /* leaf */
{
sv[svcntr] = gbt_var_leaf2node((GBT_VARKEY *) cur, tinfo);
arr[i].t = sv[svcntr];
if (sv[svcntr] != (GBT_VARKEY *) cur)
svcntr++;
}
else
arr[i].t = (GBT_VARKEY *) cur;
arr[i].i = i;
}
/* sort */
qsort_arg((void *) &arr[FirstOffsetNumber],
maxoff - FirstOffsetNumber + 1,
sizeof(Vsrt),
gbt_vsrt_cmp,
(void *) tinfo);
/* We do simply create two parts */
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
{
if (i <= (maxoff - FirstOffsetNumber + 1) / 2)
{
gbt_var_bin_union(&v->spl_ldatum, arr[i].t, tinfo);
v->spl_left[v->spl_nleft] = arr[i].i;
v->spl_nleft++;
}
else
{
gbt_var_bin_union(&v->spl_rdatum, arr[i].t, tinfo);
v->spl_right[v->spl_nright] = arr[i].i;
v->spl_nright++;
}
}
/* Truncate (=compress) key */
if (tinfo->trnc)
{
int32 ll = gbt_var_node_cp_len((GBT_VARKEY *) DatumGetPointer(v->spl_ldatum), tinfo);
int32 lr = gbt_var_node_cp_len((GBT_VARKEY *) DatumGetPointer(v->spl_rdatum), tinfo);
GBT_VARKEY *dl;
GBT_VARKEY *dr;
ll = Max(ll, lr);
ll++;
dl = gbt_var_node_truncate((GBT_VARKEY *) DatumGetPointer(v->spl_ldatum), ll, tinfo);
dr = gbt_var_node_truncate((GBT_VARKEY *) DatumGetPointer(v->spl_rdatum), ll, tinfo);
v->spl_ldatum = PointerGetDatum(dl);
v->spl_rdatum = PointerGetDatum(dr);
}
return v;
}
/*
* The GiST consistent method
*/
bool
gbt_var_consistent(
GBT_VARKEY_R *key,
const void *query,
const StrategyNumber *strategy,
bool is_leaf,
const gbtree_vinfo *tinfo
)
{
bool retval = FALSE;
switch (*strategy)
{
case BTLessEqualStrategyNumber:
if (is_leaf)
retval = (*tinfo->f_ge) (query, (void *) key->lower);
else
retval = (*tinfo->f_cmp) ((bytea *) query, key->lower) >= 0
|| gbt_var_node_pf_match(key, query, tinfo);
break;
case BTLessStrategyNumber:
if (is_leaf)
retval = (*tinfo->f_gt) (query, (void *) key->lower);
else
retval = (*tinfo->f_cmp) ((bytea *) query, key->lower) >= 0
|| gbt_var_node_pf_match(key, query, tinfo);
break;
case BTEqualStrategyNumber:
if (is_leaf)
retval = (*tinfo->f_eq) (query, (void *) key->lower);
else
retval = (
(
(*tinfo->f_cmp) (key->lower, (bytea *) query) <= 0 &&
(*tinfo->f_cmp) ((bytea *) query, (void *) key->upper) <= 0
) || gbt_var_node_pf_match(key, query, tinfo)
);
break;
case BTGreaterStrategyNumber:
if (is_leaf)
retval = (*tinfo->f_lt) (query, (void *) key->upper);
else
retval = (*tinfo->f_cmp) ((bytea *) query, key->upper) <= 0
|| gbt_var_node_pf_match(key, query, tinfo);
break;
case BTGreaterEqualStrategyNumber:
if (is_leaf)
retval = (*tinfo->f_le) (query, (void *) key->upper);
else
retval = (*tinfo->f_cmp) ((bytea *) query, key->upper) <= 0
|| gbt_var_node_pf_match(key, query, tinfo);
break;
default:
retval = FALSE;
}
return (retval);
}