postgres/contrib/intarray/_int_tool.c
Tom Lane 81b4e5ceb6 Fix longstanding error in contrib/intarray's int[] & int[] operator.
The array intersection code would give wrong results if the first entry of
the correct output array would be "1".  (I think only this value could be
at risk, since the previous word would always be a lower-bound entry with
that fixed value.)

Problem spotted by Julien Rouhaud, initial patch by Guillaume Lelarge,
cosmetic improvements by me.
2012-02-16 20:00:29 -05:00

403 lines
5.9 KiB
C

/*
* $PostgreSQL: pgsql/contrib/intarray/_int_tool.c,v 1.12 2009/06/11 14:48:51 momjian Exp $
*/
#include "postgres.h"
#include "catalog/pg_type.h"
#include "_int.h"
bool
inner_int_contains(ArrayType *a, ArrayType *b)
{
int na,
nb;
int i,
j,
n;
int *da,
*db;
CHECKARRVALID(a);
CHECKARRVALID(b);
if (ARRISVOID(a) || ARRISVOID(b))
return FALSE;
na = ARRNELEMS(a);
nb = ARRNELEMS(b);
da = ARRPTR(a);
db = ARRPTR(b);
i = j = n = 0;
while (i < na && j < nb)
if (da[i] < db[j])
i++;
else if (da[i] == db[j])
{
n++;
i++;
j++;
}
else
break;
return (n == nb) ? TRUE : FALSE;
}
bool
inner_int_overlap(ArrayType *a, ArrayType *b)
{
int na,
nb;
int i,
j;
int *da,
*db;
CHECKARRVALID(a);
CHECKARRVALID(b);
if (ARRISVOID(a) || ARRISVOID(b))
return FALSE;
na = ARRNELEMS(a);
nb = ARRNELEMS(b);
da = ARRPTR(a);
db = ARRPTR(b);
i = j = 0;
while (i < na && j < nb)
if (da[i] < db[j])
i++;
else if (da[i] == db[j])
return TRUE;
else
j++;
return FALSE;
}
ArrayType *
inner_int_union(ArrayType *a, ArrayType *b)
{
ArrayType *r = NULL;
CHECKARRVALID(a);
CHECKARRVALID(b);
if (ARRISVOID(a) && ARRISVOID(b))
return new_intArrayType(0);
if (ARRISVOID(a))
r = copy_intArrayType(b);
if (ARRISVOID(b))
r = copy_intArrayType(a);
if (!r)
{
int na = ARRNELEMS(a),
nb = ARRNELEMS(b);
int *da = ARRPTR(a),
*db = ARRPTR(b);
int i,
j,
*dr;
r = new_intArrayType(na + nb);
dr = ARRPTR(r);
/* union */
i = j = 0;
while (i < na && j < nb)
{
if (da[i] == db[j])
{
*dr++ = da[i++];
j++;
}
else if (da[i] < db[j])
*dr++ = da[i++];
else
*dr++ = db[j++];
}
while (i < na)
*dr++ = da[i++];
while (j < nb)
*dr++ = db[j++];
r = resize_intArrayType(r, dr - ARRPTR(r));
}
if (ARRNELEMS(r) > 1)
r = _int_unique(r);
return r;
}
ArrayType *
inner_int_inter(ArrayType *a, ArrayType *b)
{
ArrayType *r;
int na,
nb;
int *da,
*db,
*dr;
int i,
j,
k;
CHECKARRVALID(a);
CHECKARRVALID(b);
if (ARRISVOID(a) || ARRISVOID(b))
return new_intArrayType(0);
na = ARRNELEMS(a);
nb = ARRNELEMS(b);
da = ARRPTR(a);
db = ARRPTR(b);
r = new_intArrayType(Min(na, nb));
dr = ARRPTR(r);
i = j = k = 0;
while (i < na && j < nb)
{
if (da[i] < db[j])
i++;
else if (da[i] == db[j])
{
if (k == 0 || dr[k - 1] != db[j])
dr[k++] = db[j];
i++;
j++;
}
else
j++;
}
if (k == 0)
{
pfree(r);
return new_intArrayType(0);
}
else
return resize_intArrayType(r, k);
}
void
rt__int_size(ArrayType *a, float *size)
{
*size = (float) ARRNELEMS(a);
return;
}
/* len >= 2 */
bool
isort(int4 *a, int len)
{
int4 tmp,
index;
int4 *cur,
*end;
bool r = FALSE;
end = a + len;
do
{
index = 0;
cur = a + 1;
while (cur < end)
{
if (*(cur - 1) > *cur)
{
tmp = *(cur - 1);
*(cur - 1) = *cur;
*cur = tmp;
index = 1;
}
else if (!r && *(cur - 1) == *cur)
r = TRUE;
cur++;
}
} while (index);
return r;
}
ArrayType *
new_intArrayType(int num)
{
ArrayType *r;
int nbytes = ARR_OVERHEAD_NONULLS(NDIM) + sizeof(int) * num;
r = (ArrayType *) palloc0(nbytes);
SET_VARSIZE(r, nbytes);
ARR_NDIM(r) = NDIM;
r->dataoffset = 0; /* marker for no null bitmap */
ARR_ELEMTYPE(r) = INT4OID;
*((int *) ARR_DIMS(r)) = num;
*((int *) ARR_LBOUND(r)) = 1;
return r;
}
ArrayType *
resize_intArrayType(ArrayType *a, int num)
{
int nbytes = ARR_OVERHEAD_NONULLS(NDIM) + sizeof(int) * num;
if (num == ARRNELEMS(a))
return a;
a = (ArrayType *) repalloc(a, nbytes);
SET_VARSIZE(a, nbytes);
*((int *) ARR_DIMS(a)) = num;
return a;
}
ArrayType *
copy_intArrayType(ArrayType *a)
{
ArrayType *r;
r = new_intArrayType(ARRNELEMS(a));
memmove(r, a, VARSIZE(r));
return r;
}
/* num for compressed key */
int
internal_size(int *a, int len)
{
int i,
size = 0;
for (i = 0; i < len; i += 2)
if (!i || a[i] != a[i - 1]) /* do not count repeated range */
size += a[i + 1] - a[i] + 1;
return size;
}
/* r is sorted and size of r > 1 */
ArrayType *
_int_unique(ArrayType *r)
{
int *tmp,
*dr,
*data;
int num = ARRNELEMS(r);
CHECKARRVALID(r);
if (num < 2)
return r;
data = tmp = dr = ARRPTR(r);
while (tmp - data < num)
if (*tmp != *dr)
*(++dr) = *tmp++;
else
tmp++;
return resize_intArrayType(r, dr + 1 - ARRPTR(r));
}
void
gensign(BITVEC sign, int *a, int len)
{
int i;
/* we assume that the sign vector is previously zeroed */
for (i = 0; i < len; i++)
{
HASH(sign, *a);
a++;
}
}
int32
intarray_match_first(ArrayType *a, int32 elem)
{
int32 *aa,
c,
i;
CHECKARRVALID(a);
if (ARRISVOID(a))
return 0;
c = ARRNELEMS(a);
aa = ARRPTR(a);
for (i = 0; i < c; i++)
if (aa[i] == elem)
return (i + 1);
return 0;
}
ArrayType *
intarray_add_elem(ArrayType *a, int32 elem)
{
ArrayType *result;
int32 *r;
int32 c;
CHECKARRVALID(a);
c = (ARRISVOID(a)) ? 0 : ARRNELEMS(a);
result = new_intArrayType(c + 1);
r = ARRPTR(result);
if (c > 0)
memcpy(r, ARRPTR(a), c * sizeof(int32));
r[c] = elem;
return result;
}
ArrayType *
intarray_concat_arrays(ArrayType *a, ArrayType *b)
{
ArrayType *result;
int32 ac = (ARRISVOID(a)) ? 0 : ARRNELEMS(a);
int32 bc = (ARRISVOID(b)) ? 0 : ARRNELEMS(b);
CHECKARRVALID(a);
CHECKARRVALID(b);
result = new_intArrayType(ac + bc);
if (ac)
memcpy(ARRPTR(result), ARRPTR(a), ac * sizeof(int32));
if (bc)
memcpy(ARRPTR(result) + ac, ARRPTR(b), bc * sizeof(int32));
return result;
}
ArrayType *
int_to_intset(int32 n)
{
ArrayType *result;
int32 *aa;
result = new_intArrayType(1);
aa = ARRPTR(result);
aa[0] = n;
return result;
}
int
compASC(const void *a, const void *b)
{
if (*(int4 *) a == *(int4 *) b)
return 0;
return (*(int4 *) a > *(int4 *) b) ? 1 : -1;
}
int
compDESC(const void *a, const void *b)
{
if (*(int4 *) a == *(int4 *) b)
return 0;
return (*(int4 *) a < *(int4 *) b) ? 1 : -1;
}