postgresql/contrib/rtree_gist/rtree_gist.c
2001-05-31 18:27:18 +00:00

702 lines
19 KiB
C

/*-------------------------------------------------------------------------
*
* rtree_gist.c
* pg_amproc entries for GiSTs over 2-D boxes.
* This gives R-tree behavior, with Guttman's poly-time split algorithm.
*
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/contrib/rtree_gist/Attic/rtree_gist.c,v 1.1 2001/05/31 18:27:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/gist.h"
#include "access/itup.h"
#include "access/rtree.h"
#include "utils/palloc.h"
#include "utils/geo_decls.h"
#include "utils/elog.h"
typedef Datum (*RDF)(PG_FUNCTION_ARGS);
typedef Datum (*BINARY_UNION)(Datum, Datum, int*);
typedef float (*SIZE_BOX)(Datum);
/*
** Workaround for index_formtuple
*/
typedef struct polykey {
int32 size; /* size in varlena terms */
BOX key;
} POLYKEY;
/*
** box ops
*/
PG_FUNCTION_INFO_V1(gbox_compress);
PG_FUNCTION_INFO_V1(gbox_union);
PG_FUNCTION_INFO_V1(gbox_picksplit);
PG_FUNCTION_INFO_V1(gbox_consistent);
PG_FUNCTION_INFO_V1(gbox_penalty);
PG_FUNCTION_INFO_V1(gbox_same);
GISTENTRY * gbox_compress(PG_FUNCTION_ARGS);
BOX *gbox_union(PG_FUNCTION_ARGS);
GIST_SPLITVEC * gbox_picksplit(PG_FUNCTION_ARGS);
bool gbox_consistent(PG_FUNCTION_ARGS);
float * gbox_penalty(PG_FUNCTION_ARGS);
bool * gbox_same(PG_FUNCTION_ARGS);
static Datum gbox_binary_union(Datum r1, Datum r2, int *sizep);
static bool gbox_leaf_consistent(BOX *key, BOX *query, StrategyNumber strategy);
static float size_box( Datum box );
/*
** Polygon ops
*/
PG_FUNCTION_INFO_V1(gpoly_compress);
PG_FUNCTION_INFO_V1(gpoly_union);
PG_FUNCTION_INFO_V1(gpoly_picksplit);
PG_FUNCTION_INFO_V1(gpoly_consistent);
PG_FUNCTION_INFO_V1(gpoly_penalty);
PG_FUNCTION_INFO_V1(gpoly_same);
GISTENTRY * gpoly_compress(PG_FUNCTION_ARGS);
POLYKEY *gpoly_union(PG_FUNCTION_ARGS);
GIST_SPLITVEC * gpoly_picksplit(PG_FUNCTION_ARGS);
bool gpoly_consistent(PG_FUNCTION_ARGS);
float * gpoly_penalty(PG_FUNCTION_ARGS);
bool * gpoly_same(PG_FUNCTION_ARGS);
static Datum gpoly_binary_union(Datum r1, Datum r2, int *sizep);
static float size_polykey( Datum pk );
PG_FUNCTION_INFO_V1(gpoly_inter);
Datum gpoly_inter(PG_FUNCTION_ARGS);
/*
** Common rtree-function (for all ops)
*/
static Datum rtree_union(bytea *entryvec, int *sizep, BINARY_UNION bu);
static float * rtree_penalty(GISTENTRY *origentry, GISTENTRY *newentry,
float *result, BINARY_UNION bu, SIZE_BOX sb);
static GIST_SPLITVEC * rtree_picksplit(bytea *entryvec, GIST_SPLITVEC *v,
int keylen, BINARY_UNION bu, RDF interop, SIZE_BOX sb);
static bool rtree_internal_consistent(BOX *key, BOX *query, StrategyNumber strategy);
PG_FUNCTION_INFO_V1(rtree_decompress);
GISTENTRY * rtree_decompress(PG_FUNCTION_ARGS);
/**************************************************
* Box ops
**************************************************/
/*
** The GiST Consistent method for boxes
** Should return false if for all data items x below entry,
** the predicate x op query == FALSE, where op is the oper
** corresponding to strategy in the pg_amop table.
*/
bool
gbox_consistent(PG_FUNCTION_ARGS)
{
GISTENTRY *entry = (GISTENTRY*) PG_GETARG_POINTER(0);
BOX *query = (BOX*) PG_GETARG_POINTER(1);
StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
/*
** if entry is not leaf, use gbox_internal_consistent,
** else use gbox_leaf_consistent
*/
if ( ! (DatumGetPointer(entry->key) != NULL && query) )
return FALSE;
if (GIST_LEAF(entry))
PG_RETURN_BOOL(gbox_leaf_consistent((BOX *) DatumGetPointer(entry->key), query, strategy));
else
PG_RETURN_BOOL(rtree_internal_consistent((BOX *) DatumGetPointer(entry->key), query, strategy));
}
/*
** The GiST Union method for boxes
** returns the minimal bounding box that encloses all the entries in entryvec
*/
BOX *
gbox_union(PG_FUNCTION_ARGS)
{
return (BOX*)
DatumGetPointer(rtree_union(
(bytea*) PG_GETARG_POINTER(0),
(int*) PG_GETARG_POINTER(1),
gbox_binary_union
));
}
/*
** GiST Compress methods for boxes
** do not do anything.
*/
GISTENTRY *
gbox_compress(PG_FUNCTION_ARGS)
{
return((GISTENTRY*)PG_GETARG_POINTER(0));
}
/*
** The GiST Penalty method for boxes
** As in the R-tree paper, we use change in area as our penalty metric
*/
float *
gbox_penalty(PG_FUNCTION_ARGS)
{
return rtree_penalty(
(GISTENTRY*) PG_GETARG_POINTER(0),
(GISTENTRY*) PG_GETARG_POINTER(1),
(float*) PG_GETARG_POINTER(2),
gbox_binary_union,
size_box
);
}
/*
** The GiST PickSplit method for boxes
** We use Guttman's poly time split algorithm
*/
GIST_SPLITVEC *
gbox_picksplit(PG_FUNCTION_ARGS)
{
return rtree_picksplit(
(bytea*)PG_GETARG_POINTER(0),
(GIST_SPLITVEC*)PG_GETARG_POINTER(1),
sizeof(BOX),
gbox_binary_union,
rt_box_inter,
size_box
);
}
/*
** Equality method
*/
bool *
gbox_same(PG_FUNCTION_ARGS)
{
BOX *b1 = (BOX*) PG_GETARG_POINTER(0);
BOX *b2 = (BOX*) PG_GETARG_POINTER(1);
bool *result = (bool*) PG_GETARG_POINTER(2);
if ( b1 && b2 )
*result = DatumGetBool( DirectFunctionCall2( box_same, PointerGetDatum(b1), PointerGetDatum(b2)) );
else
*result = ( b1==NULL && b2==NULL ) ? TRUE : FALSE;
return(result);
}
/*
** SUPPORT ROUTINES for boxes
*/
static bool
gbox_leaf_consistent(BOX *key,
BOX *query,
StrategyNumber strategy)
{
bool retval;
switch(strategy) {
case RTLeftStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_left, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTOverLeftStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overleft, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTOverlapStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overlap, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTOverRightStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overright, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTRightStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_right, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTSameStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_same, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTContainsStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_contain, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTContainedByStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_contained, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
default:
retval = FALSE;
}
return(retval);
}
static Datum
gbox_binary_union(Datum r1, Datum r2, int *sizep)
{
BOX *retval;
if ( ! (DatumGetPointer(r1) != NULL && DatumGetPointer(r2) != NULL) ) {
if ( DatumGetPointer(r1) != NULL ) {
retval = (BOX*) palloc( sizeof(BOX) );
memcpy( retval, DatumGetPointer(r1), sizeof(BOX) );
*sizep = sizeof(BOX);
} else if ( DatumGetPointer(r2) != NULL ) {
retval = (BOX*) palloc( sizeof(BOX) );
memcpy( retval, DatumGetPointer(r2), sizeof(BOX) );
*sizep = sizeof(BOX);
} else {
*sizep = 0;
retval = NULL;
}
} else {
retval = (BOX*) DatumGetPointer(
DirectFunctionCall2(rt_box_union, r1, r2));
*sizep = sizeof(BOX);
}
return PointerGetDatum(retval);
}
static float
size_box( Datum box ) {
if ( DatumGetPointer(box) != NULL ) {
float size;
DirectFunctionCall2( rt_box_size,
box, PointerGetDatum( &size ) );
return size;
} else
return 0.0;
}
/**************************************************
* Polygon ops
**************************************************/
GISTENTRY *
gpoly_compress(PG_FUNCTION_ARGS)
{
GISTENTRY *entry=(GISTENTRY*)PG_GETARG_POINTER(0);
GISTENTRY *retval;
if ( entry->leafkey) {
retval = palloc(sizeof(GISTENTRY));
if ( DatumGetPointer(entry->key) != NULL ) {
POLYGON *in;
POLYKEY *r;
in = (POLYGON *) PG_DETOAST_DATUM(entry->key);
r = (POLYKEY *) palloc( sizeof(POLYKEY) );
r->size = sizeof(POLYKEY);
memcpy( (void*)&(r->key), (void*)&(in->boundbox), sizeof(BOX) );
if ( in != (POLYGON *) DatumGetPointer(entry->key) )
pfree( in );
gistentryinit(*retval, PointerGetDatum(r),
entry->rel, entry->page,
entry->offset, sizeof(POLYKEY), FALSE);
} else {
gistentryinit(*retval, (Datum) 0,
entry->rel, entry->page,
entry->offset, 0,FALSE);
}
} else {
retval = entry;
}
return( retval );
}
bool
gpoly_consistent(PG_FUNCTION_ARGS)
{
GISTENTRY *entry = (GISTENTRY*) PG_GETARG_POINTER(0);
POLYGON *query = (POLYGON*)PG_DETOAST_DATUM( PG_GETARG_POINTER(1) );
StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
bool result;
/*
** if entry is not leaf, use gbox_internal_consistent,
** else use gbox_leaf_consistent
*/
if ( ! (DatumGetPointer(entry->key) != NULL && query) )
return FALSE;
result = rtree_internal_consistent((BOX*)&( ((POLYKEY *) DatumGetPointer(entry->key))->key ),
&(query->boundbox), strategy);
PG_FREE_IF_COPY(query,1);
PG_RETURN_BOOL( result );
}
POLYKEY *
gpoly_union(PG_FUNCTION_ARGS)
{
return (POLYKEY*)
DatumGetPointer(rtree_union(
(bytea*) PG_GETARG_POINTER(0),
(int*) PG_GETARG_POINTER(1),
gpoly_binary_union
));
}
float *
gpoly_penalty(PG_FUNCTION_ARGS)
{
return rtree_penalty(
(GISTENTRY*) PG_GETARG_POINTER(0),
(GISTENTRY*) PG_GETARG_POINTER(1),
(float*) PG_GETARG_POINTER(2),
gpoly_binary_union,
size_polykey
);
}
GIST_SPLITVEC *
gpoly_picksplit(PG_FUNCTION_ARGS)
{
return rtree_picksplit(
(bytea*)PG_GETARG_POINTER(0),
(GIST_SPLITVEC*)PG_GETARG_POINTER(1),
sizeof(POLYKEY),
gpoly_binary_union,
gpoly_inter,
size_polykey
);
}
bool *
gpoly_same(PG_FUNCTION_ARGS)
{
POLYKEY *b1 = (POLYKEY*) PG_GETARG_POINTER(0);
POLYKEY *b2 = (POLYKEY*) PG_GETARG_POINTER(1);
bool *result = (bool*) PG_GETARG_POINTER(2);
if ( b1 && b2 )
*result = DatumGetBool( DirectFunctionCall2( box_same,
PointerGetDatum(&(b1->key)),
PointerGetDatum(&(b2->key))) );
else
*result = ( b1==NULL && b2==NULL ) ? TRUE : FALSE;
return(result);
}
/*
** SUPPORT ROUTINES for polygons
*/
Datum
gpoly_inter(PG_FUNCTION_ARGS)
{
POLYKEY *b1 = (POLYKEY*) PG_GETARG_POINTER(0);
POLYKEY *b2 = (POLYKEY*) PG_GETARG_POINTER(1);
Datum interd;
interd = DirectFunctionCall2(rt_box_inter,
PointerGetDatum( &(b1->key) ),
PointerGetDatum( &(b2->key) ));
if (DatumGetPointer(interd) != NULL) {
POLYKEY *tmp = (POLYKEY*) palloc( sizeof(POLYKEY) );
tmp->size = sizeof(POLYKEY);
memcpy( &(tmp->key), DatumGetPointer(interd), sizeof(BOX) );
pfree( DatumGetPointer(interd) );
PG_RETURN_POINTER( tmp );
} else
PG_RETURN_POINTER( NULL );
}
static Datum
gpoly_binary_union(Datum r1, Datum r2, int *sizep)
{
POLYKEY *retval;
if ( ! (DatumGetPointer(r1) != NULL && DatumGetPointer(r2) != NULL) ) {
if ( DatumGetPointer(r1) != NULL ) {
retval = (POLYKEY*)palloc( sizeof(POLYKEY) );
memcpy( (void*)retval, DatumGetPointer(r1), sizeof(POLYKEY) );
*sizep = sizeof(POLYKEY);
} else if ( DatumGetPointer(r2) != NULL ) {
retval = (POLYKEY*)palloc( sizeof(POLYKEY) );
memcpy( (void*)retval, DatumGetPointer(r2), sizeof(POLYKEY) );
*sizep = sizeof(POLYKEY);
} else {
*sizep = 0;
retval = NULL;
}
} else {
BOX *key = (BOX*)DatumGetPointer(
DirectFunctionCall2(
rt_box_union,
PointerGetDatum( &(((POLYKEY*) DatumGetPointer(r1))->key) ),
PointerGetDatum( &(((POLYKEY*) DatumGetPointer(r2))->key) )) );
retval = (POLYKEY*)palloc( sizeof(POLYKEY) );
memcpy( &(retval->key), key, sizeof(BOX) );
pfree( key );
*sizep = retval->size = sizeof(POLYKEY);
}
return PointerGetDatum(retval);
}
static float
size_polykey( Datum pk ) {
if ( DatumGetPointer(pk) != NULL ) {
float size;
DirectFunctionCall2( rt_box_size,
PointerGetDatum( &(((POLYKEY*) DatumGetPointer(pk))->key) ),
PointerGetDatum( &size ) );
return size;
} else
return 0.0;
}
/*
** Common rtree-function (for all ops)
*/
static Datum
rtree_union(bytea *entryvec, int *sizep, BINARY_UNION bu)
{
int numranges, i;
Datum out,
tmp;
numranges = (VARSIZE(entryvec) - VARHDRSZ)/sizeof(GISTENTRY);
tmp = ((GISTENTRY *) VARDATA(entryvec))[0].key;
out = (Datum) 0;
for (i = 1; i < numranges; i++) {
out = (*bu)(tmp,
((GISTENTRY *) VARDATA(entryvec))[i].key,
sizep);
if (i > 1 && DatumGetPointer(tmp) != NULL)
pfree(DatumGetPointer(tmp));
tmp = out;
}
return(out);
}
static float *
rtree_penalty(GISTENTRY *origentry, GISTENTRY *newentry, float *result, BINARY_UNION bu, SIZE_BOX sb)
{
Datum ud;
float tmp1;
int sizep;
ud = (*bu)( origentry->key, newentry->key, &sizep );
tmp1 = (*sb)( ud );
if (DatumGetPointer(ud) != NULL) pfree(DatumGetPointer(ud));
*result = tmp1 - (*sb)( origentry->key );
return(result);
}
/*
** The GiST PickSplit method
** We use Guttman's poly time split algorithm
*/
static GIST_SPLITVEC *
rtree_picksplit(bytea *entryvec, GIST_SPLITVEC *v, int keylen, BINARY_UNION bu, RDF interop, SIZE_BOX sb)
{
OffsetNumber i, j;
Datum datum_alpha, datum_beta;
Datum datum_l, datum_r;
Datum union_d, union_dl, union_dr;
Datum inter_d;
bool firsttime;
float size_alpha, size_beta, size_union, size_inter;
float size_waste, waste;
float size_l, size_r;
int nbytes;
int sizep;
OffsetNumber seed_1 = 0, seed_2 = 0;
OffsetNumber *left, *right;
OffsetNumber maxoff;
maxoff = ((VARSIZE(entryvec) - VARHDRSZ)/sizeof(GISTENTRY)) - 2;
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
v->spl_left = (OffsetNumber *) palloc(nbytes);
v->spl_right = (OffsetNumber *) palloc(nbytes);
firsttime = true;
waste = 0.0;
for (i = FirstOffsetNumber; i < maxoff; i = OffsetNumberNext(i)) {
datum_alpha = ((GISTENTRY *) VARDATA(entryvec))[i].key;
for (j = OffsetNumberNext(i); j <= maxoff; j = OffsetNumberNext(j)) {
datum_beta = ((GISTENTRY *) VARDATA(entryvec))[j].key;
/* compute the wasted space by unioning these guys */
/* size_waste = size_union - size_inter; */
union_d = (*bu)( datum_alpha, datum_beta, &sizep );
if ( DatumGetPointer(union_d) != NULL ) {
size_union = (*sb)(union_d);
pfree(DatumGetPointer(union_d));
} else
size_union = 0.0;
if ( DatumGetPointer(datum_alpha) != NULL &&
DatumGetPointer(datum_beta) != NULL ) {
inter_d = DirectFunctionCall2(interop,
datum_alpha,
datum_beta);
if ( DatumGetPointer(inter_d) != NULL ) {
size_inter = (*sb)(inter_d);
pfree(DatumGetPointer(inter_d));
} else
size_inter = 0.0;
} else
size_inter = 0.0;
size_waste = size_union - size_inter;
/*
* are these a more promising split that what we've
* already seen?
*/
if (size_waste > waste || firsttime) {
waste = size_waste;
seed_1 = i;
seed_2 = j;
firsttime = false;
}
}
}
left = v->spl_left;
v->spl_nleft = 0;
right = v->spl_right;
v->spl_nright = 0;
if ( DatumGetPointer(((GISTENTRY *) VARDATA(entryvec))[seed_1].key) != NULL )
{
datum_l = PointerGetDatum(palloc( keylen ));
memcpy(DatumGetPointer(datum_l),
DatumGetPointer(((GISTENTRY *) VARDATA(entryvec))[seed_1].key),
keylen);
} else
datum_l = (Datum) 0;
size_l = (*sb)( datum_l );
if ( DatumGetPointer(((GISTENTRY *) VARDATA(entryvec))[seed_2].key) != NULL )
{
datum_r = PointerGetDatum(palloc( keylen ));
memcpy(DatumGetPointer(datum_r),
DatumGetPointer(((GISTENTRY *) VARDATA(entryvec))[seed_2].key),
keylen);
} else
datum_r = (Datum) 0;
size_r = (*sb)( datum_r );
/*
* Now split up the regions between the two seeds. An important
* property of this split algorithm is that the split vector v
* has the indices of items to be split in order in its left and
* right vectors. We exploit this property by doing a merge in
* the code that actually splits the page.
*
* For efficiency, we also place the new index tuple in this loop.
* This is handled at the very end, when we have placed all the
* existing tuples and i == maxoff + 1.
*/
maxoff = OffsetNumberNext(maxoff);
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i)) {
/*
* If we've already decided where to place this item, just
* put it on the right list. Otherwise, we need to figure
* out which page needs the least enlargement in order to
* store the item.
*/
if (i == seed_1) {
*left++ = i;
v->spl_nleft++;
continue;
} else if (i == seed_2) {
*right++ = i;
v->spl_nright++;
continue;
}
/* okay, which page needs least enlargement? */
datum_alpha = ((GISTENTRY *) VARDATA(entryvec))[i].key;
union_dl = (*bu)( datum_l, datum_alpha, &sizep );
union_dr = (*bu)( datum_r, datum_alpha, &sizep );
size_alpha = (*sb)( union_dl );
size_beta = (*sb)( union_dr );
/* pick which page to add it to */
if (size_alpha - size_l < size_beta - size_r) {
pfree(DatumGetPointer(datum_l));
pfree(DatumGetPointer(union_dr));
datum_l = union_dl;
size_l = size_alpha;
*left++ = i;
v->spl_nleft++;
} else {
pfree(DatumGetPointer(datum_r));
pfree(DatumGetPointer(union_dl));
datum_r = union_dr;
size_r = size_alpha;
*right++ = i;
v->spl_nright++;
}
}
*left = *right = FirstOffsetNumber; /* sentinel value, see dosplit() */
v->spl_ldatum = datum_l;
v->spl_rdatum = datum_r;
return( v );
}
static bool
rtree_internal_consistent(BOX *key,
BOX *query,
StrategyNumber strategy)
{
bool retval;
switch(strategy) {
case RTLeftStrategyNumber:
case RTOverLeftStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overleft, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTOverlapStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overlap, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTOverRightStrategyNumber:
case RTRightStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_right, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTSameStrategyNumber:
case RTContainsStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_contain, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
case RTContainedByStrategyNumber:
retval = DatumGetBool( DirectFunctionCall2( box_overlap, PointerGetDatum(key), PointerGetDatum(query) ) );
break;
default:
retval = FALSE;
}
return(retval);
}
/*
** GiST DeCompress methods
** do not do anything.
*/
GISTENTRY *
rtree_decompress(PG_FUNCTION_ARGS)
{
return((GISTENTRY*)PG_GETARG_POINTER(0));
}