postgresql/contrib/hstore/hstore_gist.c
Tom Lane 3e23b68dac Support varlena fields with single-byte headers and unaligned storage.
This commit breaks any code that assumes that the mere act of forming a tuple
(without writing it to disk) does not "toast" any fields.  While all available
regression tests pass, I'm not totally sure that we've fixed every nook and
cranny, especially in contrib.

Greg Stark with some help from Tom Lane
2007-04-06 04:21:44 +00:00

558 lines
12 KiB
C

#include "hstore.h"
#include "access/gist.h"
#include "access/itup.h"
#include "crc32.h"
/* bigint defines */
#define BITBYTE 8
#define SIGLENINT 4 /* >122 => key will toast, so very slow!!! */
#define SIGLEN ( sizeof(int)*SIGLENINT )
#define SIGLENBIT (SIGLEN*BITBYTE)
typedef char BITVEC[SIGLEN];
typedef char *BITVECP;
#define SIGPTR(x) ( (BITVECP) ARR_DATA_PTR(x) )
#define LOOPBYTE(a) \
for(i=0;i<SIGLEN;i++) {\
a;\
}
#define LOOPBIT(a) \
for(i=0;i<SIGLENBIT;i++) {\
a;\
}
/* beware of multiple evaluation of arguments to these macros! */
#define GETBYTE(x,i) ( *( (BITVECP)(x) + (int)( (i) / BITBYTE ) ) )
#define GETBITBYTE(x,i) ( (*((char*)(x)) >> (i)) & 0x01 )
#define CLRBIT(x,i) GETBYTE(x,i) &= ~( 0x01 << ( (i) % BITBYTE ) )
#define SETBIT(x,i) GETBYTE(x,i) |= ( 0x01 << ( (i) % BITBYTE ) )
#define GETBIT(x,i) ( (GETBYTE(x,i) >> ( (i) % BITBYTE )) & 0x01 )
#define HASHVAL(val) (((unsigned int)(val)) % SIGLENBIT)
#define HASH(sign, val) SETBIT((sign), HASHVAL(val))
typedef struct
{
int32 vl_len_; /* varlena header (do not touch directly!) */
int4 flag;
char data[1];
} GISTTYPE;
#define ALLISTRUE 0x04
#define ISALLTRUE(x) ( ((GISTTYPE*)x)->flag & ALLISTRUE )
#define GTHDRSIZE (VARHDRSZ + sizeof(int4))
#define CALCGTSIZE(flag) ( GTHDRSIZE+(((flag) & ALLISTRUE) ? 0 : SIGLEN) )
#define GETSIGN(x) ( (BITVECP)( (char*)x+GTHDRSIZE ) )
#define SUMBIT(val) ( \
GETBITBYTE((val),0) + \
GETBITBYTE((val),1) + \
GETBITBYTE((val),2) + \
GETBITBYTE((val),3) + \
GETBITBYTE((val),4) + \
GETBITBYTE((val),5) + \
GETBITBYTE((val),6) + \
GETBITBYTE((val),7) \
)
#define GETENTRY(vec,pos) ((GISTTYPE *) DatumGetPointer((vec)->vector[(pos)].key))
#define WISH_F(a,b,c) (double)( -(double)(((a)-(b))*((a)-(b))*((a)-(b)))*(c) )
PG_FUNCTION_INFO_V1(ghstore_in);
Datum ghstore_in(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(ghstore_out);
Datum ghstore_out(PG_FUNCTION_ARGS);
Datum
ghstore_in(PG_FUNCTION_ARGS)
{
elog(ERROR, "Not implemented");
PG_RETURN_DATUM(0);
}
Datum
ghstore_out(PG_FUNCTION_ARGS)
{
elog(ERROR, "Not implemented");
PG_RETURN_DATUM(0);
}
PG_FUNCTION_INFO_V1(ghstore_consistent);
PG_FUNCTION_INFO_V1(ghstore_compress);
PG_FUNCTION_INFO_V1(ghstore_decompress);
PG_FUNCTION_INFO_V1(ghstore_penalty);
PG_FUNCTION_INFO_V1(ghstore_picksplit);
PG_FUNCTION_INFO_V1(ghstore_union);
PG_FUNCTION_INFO_V1(ghstore_same);
Datum ghstore_consistent(PG_FUNCTION_ARGS);
Datum ghstore_compress(PG_FUNCTION_ARGS);
Datum ghstore_decompress(PG_FUNCTION_ARGS);
Datum ghstore_penalty(PG_FUNCTION_ARGS);
Datum ghstore_picksplit(PG_FUNCTION_ARGS);
Datum ghstore_union(PG_FUNCTION_ARGS);
Datum ghstore_same(PG_FUNCTION_ARGS);
Datum
ghstore_compress(PG_FUNCTION_ARGS)
{
GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
GISTENTRY *retval = entry;
if (entry->leafkey)
{
GISTTYPE *res = (GISTTYPE *) palloc0(CALCGTSIZE(0));
HStore *toastedval = (HStore *) DatumGetPointer(entry->key);
HStore *val = (HStore *) DatumGetPointer(PG_DETOAST_DATUM(entry->key));
HEntry *ptr = ARRPTR(val);
char *words = STRPTR(val);
SET_VARSIZE(res, CALCGTSIZE(0));
while (ptr - ARRPTR(val) < val->size)
{
int h;
h = crc32_sz((char *) (words + ptr->pos), ptr->keylen);
HASH(GETSIGN(res), h);
if (!ptr->valisnull)
{
h = crc32_sz((char *) (words + ptr->pos + ptr->keylen), ptr->vallen);
HASH(GETSIGN(res), h);
}
ptr++;
}
if (val != toastedval)
pfree(val);
retval = (GISTENTRY *) palloc(sizeof(GISTENTRY));
gistentryinit(*retval, PointerGetDatum(res),
entry->rel, entry->page,
entry->offset,
FALSE);
}
else if (!ISALLTRUE(DatumGetPointer(entry->key)))
{
int4 i;
GISTTYPE *res;
BITVECP sign = GETSIGN(DatumGetPointer(entry->key));
LOOPBYTE(
if ((sign[i] & 0xff) != 0xff)
PG_RETURN_POINTER(retval);
);
res = (GISTTYPE *) palloc(CALCGTSIZE(ALLISTRUE));
SET_VARSIZE(res, CALCGTSIZE(ALLISTRUE));
res->flag = ALLISTRUE;
retval = (GISTENTRY *) palloc(sizeof(GISTENTRY));
gistentryinit(*retval, PointerGetDatum(res),
entry->rel, entry->page,
entry->offset,
FALSE);
}
PG_RETURN_POINTER(retval);
}
Datum
ghstore_decompress(PG_FUNCTION_ARGS)
{
GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
GISTENTRY *retval;
HStore *key;
key = (HStore *) PG_DETOAST_DATUM(entry->key);
if (key != (HStore *) DatumGetPointer(entry->key))
{
/* need to pass back the decompressed item */
retval = palloc(sizeof(GISTENTRY));
gistentryinit(*retval, PointerGetDatum(key),
entry->rel, entry->page, entry->offset, entry->leafkey);
PG_RETURN_POINTER(retval);
}
else
{
/* we can return the entry as-is */
PG_RETURN_POINTER(entry);
}
}
Datum
ghstore_same(PG_FUNCTION_ARGS)
{
GISTTYPE *a = (GISTTYPE *) PG_GETARG_POINTER(0);
GISTTYPE *b = (GISTTYPE *) PG_GETARG_POINTER(1);
bool *result = (bool *) PG_GETARG_POINTER(2);
if (ISALLTRUE(a) && ISALLTRUE(b))
*result = true;
else if (ISALLTRUE(a))
*result = false;
else if (ISALLTRUE(b))
*result = false;
else
{
int4 i;
BITVECP sa = GETSIGN(a),
sb = GETSIGN(b);
*result = true;
LOOPBYTE(
if (sa[i] != sb[i])
{
*result = false;
break;
}
);
}
PG_RETURN_POINTER(result);
}
static int4
sizebitvec(BITVECP sign)
{
int4 size = 0,
i;
LOOPBYTE(
size += SUMBIT(sign);
sign = (BITVECP) (((char *) sign) + 1);
);
return size;
}
static int
hemdistsign(BITVECP a, BITVECP b)
{
int i,
dist = 0;
LOOPBIT(
if (GETBIT(a, i) != GETBIT(b, i))
dist++;
);
return dist;
}
static int
hemdist(GISTTYPE * a, GISTTYPE * b)
{
if (ISALLTRUE(a))
{
if (ISALLTRUE(b))
return 0;
else
return SIGLENBIT - sizebitvec(GETSIGN(b));
}
else if (ISALLTRUE(b))
return SIGLENBIT - sizebitvec(GETSIGN(a));
return hemdistsign(GETSIGN(a), GETSIGN(b));
}
static int4
unionkey(BITVECP sbase, GISTTYPE * add)
{
int4 i;
BITVECP sadd = GETSIGN(add);
if (ISALLTRUE(add))
return 1;
LOOPBYTE(
sbase[i] |= sadd[i];
);
return 0;
}
Datum
ghstore_union(PG_FUNCTION_ARGS)
{
GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
int4 len = entryvec->n;
int *size = (int *) PG_GETARG_POINTER(1);
BITVEC base;
int4 i;
int4 flag = 0;
GISTTYPE *result;
MemSet((void *) base, 0, sizeof(BITVEC));
for (i = 0; i < len; i++)
{
if (unionkey(base, GETENTRY(entryvec, i)))
{
flag = ALLISTRUE;
break;
}
}
len = CALCGTSIZE(flag);
result = (GISTTYPE *) palloc(len);
SET_VARSIZE(result, len);
result->flag = flag;
if (!ISALLTRUE(result))
memcpy((void *) GETSIGN(result), (void *) base, sizeof(BITVEC));
*size = len;
PG_RETURN_POINTER(result);
}
Datum
ghstore_penalty(PG_FUNCTION_ARGS)
{
GISTENTRY *origentry = (GISTENTRY *) PG_GETARG_POINTER(0); /* always ISSIGNKEY */
GISTENTRY *newentry = (GISTENTRY *) PG_GETARG_POINTER(1);
float *penalty = (float *) PG_GETARG_POINTER(2);
GISTTYPE *origval = (GISTTYPE *) DatumGetPointer(origentry->key);
GISTTYPE *newval = (GISTTYPE *) DatumGetPointer(newentry->key);
*penalty = hemdist(origval, newval);
PG_RETURN_POINTER(penalty);
}
typedef struct
{
OffsetNumber pos;
int4 cost;
} SPLITCOST;
static int
comparecost(const void *a, const void *b)
{
return ((SPLITCOST *) a)->cost - ((SPLITCOST *) b)->cost;
}
Datum
ghstore_picksplit(PG_FUNCTION_ARGS)
{
GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
OffsetNumber maxoff = entryvec->n - 2;
GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
OffsetNumber k,
j;
GISTTYPE *datum_l,
*datum_r;
BITVECP union_l,
union_r;
int4 size_alpha,
size_beta;
int4 size_waste,
waste = -1;
int4 nbytes;
OffsetNumber seed_1 = 0,
seed_2 = 0;
OffsetNumber *left,
*right;
BITVECP ptr;
int i;
SPLITCOST *costvector;
GISTTYPE *_k,
*_j;
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
v->spl_left = (OffsetNumber *) palloc(nbytes);
v->spl_right = (OffsetNumber *) palloc(nbytes);
for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k))
{
_k = GETENTRY(entryvec, k);
for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j))
{
size_waste = hemdist(_k, GETENTRY(entryvec, j));
if (size_waste > waste)
{
waste = size_waste;
seed_1 = k;
seed_2 = j;
}
}
}
left = v->spl_left;
v->spl_nleft = 0;
right = v->spl_right;
v->spl_nright = 0;
if (seed_1 == 0 || seed_2 == 0)
{
seed_1 = 1;
seed_2 = 2;
}
/* form initial .. */
if (ISALLTRUE(GETENTRY(entryvec, seed_1)))
{
datum_l = (GISTTYPE *) palloc(GTHDRSIZE);
SET_VARSIZE(datum_l, GTHDRSIZE);
datum_l->flag = ALLISTRUE;
}
else
{
datum_l = (GISTTYPE *) palloc(GTHDRSIZE + SIGLEN);
SET_VARSIZE(datum_l, GTHDRSIZE + SIGLEN);
datum_l->flag = 0;
memcpy((void *) GETSIGN(datum_l), (void *) GETSIGN(GETENTRY(entryvec, seed_1)), sizeof(BITVEC))
;
}
if (ISALLTRUE(GETENTRY(entryvec, seed_2)))
{
datum_r = (GISTTYPE *) palloc(GTHDRSIZE);
SET_VARSIZE(datum_r, GTHDRSIZE);
datum_r->flag = ALLISTRUE;
}
else
{
datum_r = (GISTTYPE *) palloc(GTHDRSIZE + SIGLEN);
SET_VARSIZE(datum_r, GTHDRSIZE + SIGLEN);
datum_r->flag = 0;
memcpy((void *) GETSIGN(datum_r), (void *) GETSIGN(GETENTRY(entryvec, seed_2)), sizeof(BITVEC));
}
maxoff = OffsetNumberNext(maxoff);
/* sort before ... */
costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j))
{
costvector[j - 1].pos = j;
_j = GETENTRY(entryvec, j);
size_alpha = hemdist(datum_l, _j);
size_beta = hemdist(datum_r, _j);
costvector[j - 1].cost = abs(size_alpha - size_beta);
}
qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
union_l = GETSIGN(datum_l);
union_r = GETSIGN(datum_r);
for (k = 0; k < maxoff; k++)
{
j = costvector[k].pos;
if (j == seed_1)
{
*left++ = j;
v->spl_nleft++;
continue;
}
else if (j == seed_2)
{
*right++ = j;
v->spl_nright++;
continue;
}
_j = GETENTRY(entryvec, j);
size_alpha = hemdist(datum_l, _j);
size_beta = hemdist(datum_r, _j);
if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.0001))
{
if (ISALLTRUE(datum_l) || ISALLTRUE(_j))
{
if (!ISALLTRUE(datum_l))
MemSet((void *) union_l, 0xff, sizeof(BITVEC));
}
else
{
ptr = GETSIGN(_j);
LOOPBYTE(
union_l[i] |= ptr[i];
);
}
*left++ = j;
v->spl_nleft++;
}
else
{
if (ISALLTRUE(datum_r) || ISALLTRUE(_j))
{
if (!ISALLTRUE(datum_r))
MemSet((void *) union_r, 0xff, sizeof(BITVEC));
}
else
{
ptr = GETSIGN(_j);
LOOPBYTE(
union_r[i] |= ptr[i];
);
}
*right++ = j;
v->spl_nright++;
}
}
*right = *left = FirstOffsetNumber;
pfree(costvector);
v->spl_ldatum = PointerGetDatum(datum_l);
v->spl_rdatum = PointerGetDatum(datum_r);
PG_RETURN_POINTER(v);
}
Datum
ghstore_consistent(PG_FUNCTION_ARGS)
{
GISTTYPE *entry = (GISTTYPE *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
bool res = true;
BITVECP sign;
if (ISALLTRUE(entry))
PG_RETURN_BOOL(true);
sign = GETSIGN(entry);
if ( strategy == HStoreContainsStrategyNumber || strategy == 13 /* hack for old strats */ )
{
HStore *query = PG_GETARG_HS(1);
HEntry *qe = ARRPTR(query);
char *qv = STRPTR(query);
while (res && qe - ARRPTR(query) < query->size)
{
int crc = crc32_sz((char *) (qv + qe->pos), qe->keylen);
if (GETBIT(sign, HASHVAL(crc)))
{
if (!qe->valisnull)
{
crc = crc32_sz((char *) (qv + qe->pos + qe->keylen), qe->vallen);
if (!GETBIT(sign, HASHVAL(crc)))
res = false;
}
}
else
res = false;
qe++;
}
}
else if ( strategy == HStoreExistsStrategyNumber )
{
text *query = PG_GETARG_TEXT_P(1);
int crc = crc32_sz( VARDATA(query), VARSIZE(query)-VARHDRSZ );
res = (GETBIT(sign, HASHVAL(crc))) ? true : false;
}
else
elog(ERROR, "Unsupported strategy number: %d", strategy);
PG_RETURN_BOOL(res);
}