1
0
mirror of https://github.com/postgres/postgres.git synced 2025-06-16 06:01:02 +03:00

Make SQL arrays support null elements. This commit fixes the core array

functionality, but I still need to make another pass looking at places
that incidentally use arrays (such as ACL manipulation) to make sure they
are null-safe.  Contrib needs work too.
I have not changed the behaviors that are still under discussion about
array comparison and what to do with lower bounds.
This commit is contained in:
Tom Lane
2005-11-17 22:14:56 +00:00
parent c859308aba
commit cecb607559
35 changed files with 2149 additions and 950 deletions

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/arrayutils.c,v 1.18 2004/12/31 22:01:21 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/arrayutils.c,v 1.19 2005/11/17 22:14:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -16,11 +16,17 @@
#include "postgres.h"
#include "utils/array.h"
#include "utils/memutils.h"
/* Convert subscript list into linear element number (from 0) */
/*
* Convert subscript list into linear element number (from 0)
*
* We assume caller has already range-checked the dimensions and subscripts,
* so no overflow is possible.
*/
int
ArrayGetOffset(int n, int *dim, int *lb, int *indx)
ArrayGetOffset(int n, const int *dim, const int *lb, const int *indx)
{
int i,
scale = 1,
@ -34,11 +40,12 @@ ArrayGetOffset(int n, int *dim, int *lb, int *indx)
return offset;
}
/* Same, but subscripts are assumed 0-based, and use a scale array
/*
* Same, but subscripts are assumed 0-based, and use a scale array
* instead of raw dimension data (see mda_get_prod to create scale array)
*/
int
ArrayGetOffset0(int n, int *tup, int *scale)
ArrayGetOffset0(int n, const int *tup, const int *scale)
{
int i,
lin = 0;
@ -48,24 +55,66 @@ ArrayGetOffset0(int n, int *tup, int *scale)
return lin;
}
/* Convert array dimensions into number of elements */
/*
* Convert array dimensions into number of elements
*
* This must do overflow checking, since it is used to validate that a user
* dimensionality request doesn't overflow what we can handle.
*
* We limit array sizes to at most about a quarter billion elements,
* so that it's not necessary to check for overflow in quite so many
* places --- for instance when palloc'ing Datum arrays.
*
* The multiplication overflow check only works on machines that have int64
* arithmetic, but that is nearly all platforms these days, and doing check
* divides for those that don't seems way too expensive.
*/
int
ArrayGetNItems(int ndim, int *dims)
ArrayGetNItems(int ndim, const int *dims)
{
int i,
ret;
int32 ret;
int i;
#define MaxArraySize ((Size) (MaxAllocSize / sizeof(Datum)))
if (ndim <= 0)
return 0;
ret = 1;
for (i = 0; i < ndim; i++)
ret *= dims[i];
return ret;
{
int64 prod;
/* A negative dimension implies that UB-LB overflowed ... */
if (dims[i] < 0)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("array size exceeds the maximum allowed (%d)",
(int) MaxArraySize)));
prod = (int64) ret * (int64) dims[i];
ret = (int32) prod;
if ((int64) ret != prod)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("array size exceeds the maximum allowed (%d)",
(int) MaxArraySize)));
}
Assert(ret >= 0);
if ((Size) ret > MaxArraySize)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("array size exceeds the maximum allowed (%d)",
(int) MaxArraySize)));
return (int) ret;
}
/* Compute ranges (sub-array dimensions) for an array slice */
/*
* Compute ranges (sub-array dimensions) for an array slice
*
* We assume caller has validated slice endpoints, so overflow is impossible
*/
void
mda_get_range(int n, int *span, int *st, int *endp)
mda_get_range(int n, int *span, const int *st, const int *endp)
{
int i;
@ -73,9 +122,13 @@ mda_get_range(int n, int *span, int *st, int *endp)
span[i] = endp[i] - st[i] + 1;
}
/* Compute products of array dimensions, ie, scale factors for subscripts */
/*
* Compute products of array dimensions, ie, scale factors for subscripts
*
* We assume caller has validated dimensions, so overflow is impossible
*/
void
mda_get_prod(int n, int *range, int *prod)
mda_get_prod(int n, const int *range, int *prod)
{
int i;
@ -84,11 +137,14 @@ mda_get_prod(int n, int *range, int *prod)
prod[i] = prod[i + 1] * range[i + 1];
}
/* From products of whole-array dimensions and spans of a sub-array,
/*
* From products of whole-array dimensions and spans of a sub-array,
* compute offset distances needed to step through subarray within array
*
* We assume caller has validated dimensions, so overflow is impossible
*/
void
mda_get_offset_values(int n, int *dist, int *prod, int *span)
mda_get_offset_values(int n, int *dist, const int *prod, const int *span)
{
int i,
j;
@ -102,16 +158,18 @@ mda_get_offset_values(int n, int *dist, int *prod, int *span)
}
}
/*-----------------------------------------------------------------------------
generates the tuple that is lexicographically one greater than the current
n-tuple in "curr", with the restriction that the i-th element of "curr" is
less than the i-th element of "span".
Returns -1 if no next tuple exists, else the subscript position (0..n-1)
corresponding to the dimension to advance along.
-----------------------------------------------------------------------------
*/
/*
* Generates the tuple that is lexicographically one greater than the current
* n-tuple in "curr", with the restriction that the i-th element of "curr" is
* less than the i-th element of "span".
*
* Returns -1 if no next tuple exists, else the subscript position (0..n-1)
* corresponding to the dimension to advance along.
*
* We assume caller has validated dimensions, so overflow is impossible
*/
int
mda_next_tuple(int n, int *curr, int *span)
mda_next_tuple(int n, int *curr, const int *span)
{
int i;