Re: Manipulating complex types as non-contiguous structures in-memory - Mailing list pgsql-hackers
| From | Tom Lane |
|---|---|
| Subject | Re: Manipulating complex types as non-contiguous structures in-memory |
| Date | |
| Msg-id | 1960.1424043707@sss.pgh.pa.us Whole thread Raw |
| In response to | Re: Manipulating complex types as non-contiguous structures in-memory (Tom Lane <tgl@sss.pgh.pa.us>) |
| Responses |
Re: Manipulating complex types as non-contiguous structures in-memory
(Robert Haas <robertmhaas@gmail.com>)
Re: Manipulating complex types as non-contiguous structures in-memory (Tom Lane <tgl@sss.pgh.pa.us>) |
| List | pgsql-hackers |
Here's an updated version of the patch I sent before. Notable changes:
* I switched over to calling "deserialized" objects "expanded" objects,
and the default representation is now called "flat" or "flattened" instead
of "reserialized". Per suggestion from Robert.
* I got rid of the bit about detecting read-write pointers by address
comparison. Instead there are now two vartag values for R/W and R/O
pointers. After further reflection I concluded that my previous worry
about wanting copied pointers to automatically become read-only was
probably wrong, so there's no need for extra confusion here.
* I added support for extracting array elements from expanded values
(array_ref).
* I hacked plpgsql to force values of array-type variables into expanded
form; this is needed to get any win from the array_ref change if the
function doesn't do any assignments to elements of the array. This is an
improvement over the original patch, which hardwired array_set to force
expansion, but I remain unsatisfied with it as a long-term answer. It's
not clear that it's always a win to do this (but the tradeoff will change
as we convert more array support functions to handle expanded inputs, so
it's probably not worth getting too excited about that aspect of it yet).
A bigger complaint is that this approach cannot fix things for non-builtin
types such as hstore. I'm hesitant to add a pg_type column carrying an
expansion function OID, but there may be no other workable answer for
extension types.
The patch as it stands is able to do nice things with
create or replace function arraysetnum(n int) returns numeric[] as $$
declare res numeric[] := '{}';
begin
for i in 1 .. n loop
res[i] := i;
end loop;
return res;
end
$$ language plpgsql strict;
create or replace function arraysumnum(arr numeric[]) returns numeric as $$
declare res numeric := 0;
begin
for i in array_lower(arr, 1) .. array_upper(arr, 1) loop
res := res + arr[i];
end loop;
return res;
end
$$ language plpgsql strict;
regression=# select arraysumnum(arraysetnum(100000));
arraysumnum
-------------
5000050000
(1 row)
Time: 304.336 ms
(versus approximately 1 minute in 9.4, although these numbers are for
cassert builds so should be taken with a grain of salt.) There are
still a couple more flattening/expansion conversions than I'd like,
in particular the array returned by arraysetnum() gets flattened on its
way out, which would be good to avoid.
I'm going to stick this into the commitfest even though it's not really
close to being committable; I see some other people doing likewise with
their pet patches ;-). What it could particularly do with some reviewing
help on is exploring the performance changes it creates; what cases does
it make substantially worse?
regards, tom lane
diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
index 867035d..860ad78 100644
*** a/src/backend/access/common/heaptuple.c
--- b/src/backend/access/common/heaptuple.c
***************
*** 60,65 ****
--- 60,66 ----
#include "access/sysattr.h"
#include "access/tuptoaster.h"
#include "executor/tuptable.h"
+ #include "utils/expandeddatum.h"
/* Does att's datatype allow packing into the 1-byte-header varlena format? */
*************** heap_compute_data_size(TupleDesc tupleDe
*** 93,105 ****
for (i = 0; i < numberOfAttributes; i++)
{
Datum val;
if (isnull[i])
continue;
val = values[i];
! if (ATT_IS_PACKABLE(att[i]) &&
VARATT_CAN_MAKE_SHORT(DatumGetPointer(val)))
{
/*
--- 94,108 ----
for (i = 0; i < numberOfAttributes; i++)
{
Datum val;
+ Form_pg_attribute atti;
if (isnull[i])
continue;
val = values[i];
+ atti = att[i];
! if (ATT_IS_PACKABLE(atti) &&
VARATT_CAN_MAKE_SHORT(DatumGetPointer(val)))
{
/*
*************** heap_compute_data_size(TupleDesc tupleDe
*** 108,118 ****
*/
data_length += VARATT_CONVERTED_SHORT_SIZE(DatumGetPointer(val));
}
else
{
! data_length = att_align_datum(data_length, att[i]->attalign,
! att[i]->attlen, val);
! data_length = att_addlength_datum(data_length, att[i]->attlen,
val);
}
}
--- 111,131 ----
*/
data_length += VARATT_CONVERTED_SHORT_SIZE(DatumGetPointer(val));
}
+ else if (atti->attlen == -1 &&
+ VARATT_IS_EXTERNAL_EXPANDED(DatumGetPointer(val)))
+ {
+ /*
+ * we want to flatten the expanded value so that the constructed
+ * tuple doesn't depend on it
+ */
+ data_length = att_align_nominal(data_length, atti->attalign);
+ data_length += EOH_get_flat_size(DatumGetEOHP(val));
+ }
else
{
! data_length = att_align_datum(data_length, atti->attalign,
! atti->attlen, val);
! data_length = att_addlength_datum(data_length, atti->attlen,
val);
}
}
*************** heap_fill_tuple(TupleDesc tupleDesc,
*** 203,212 ****
*infomask |= HEAP_HASVARWIDTH;
if (VARATT_IS_EXTERNAL(val))
{
! *infomask |= HEAP_HASEXTERNAL;
! /* no alignment, since it's short by definition */
! data_length = VARSIZE_EXTERNAL(val);
! memcpy(data, val, data_length);
}
else if (VARATT_IS_SHORT(val))
{
--- 216,241 ----
*infomask |= HEAP_HASVARWIDTH;
if (VARATT_IS_EXTERNAL(val))
{
! if (VARATT_IS_EXTERNAL_EXPANDED(val))
! {
! /*
! * we want to flatten the expanded value so that the
! * constructed tuple doesn't depend on it
! */
! ExpandedObjectHeader *eoh = DatumGetEOHP(values[i]);
!
! data = (char *) att_align_nominal(data,
! att[i]->attalign);
! data_length = EOH_get_flat_size(eoh);
! EOH_flatten_into(eoh, data, data_length);
! }
! else
! {
! *infomask |= HEAP_HASEXTERNAL;
! /* no alignment, since it's short by definition */
! data_length = VARSIZE_EXTERNAL(val);
! memcpy(data, val, data_length);
! }
}
else if (VARATT_IS_SHORT(val))
{
diff --git a/src/backend/access/heap/tuptoaster.c b/src/backend/access/heap/tuptoaster.c
index f8c1401..ebcbbc4 100644
*** a/src/backend/access/heap/tuptoaster.c
--- b/src/backend/access/heap/tuptoaster.c
***************
*** 37,42 ****
--- 37,43 ----
#include "catalog/catalog.h"
#include "common/pg_lzcompress.h"
#include "miscadmin.h"
+ #include "utils/expandeddatum.h"
#include "utils/fmgroids.h"
#include "utils/rel.h"
#include "utils/typcache.h"
*************** heap_tuple_fetch_attr(struct varlena * a
*** 130,135 ****
--- 131,149 ----
result = (struct varlena *) palloc(VARSIZE_ANY(attr));
memcpy(result, attr, VARSIZE_ANY(attr));
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+ {
+ /*
+ * This is an expanded-object pointer --- get flat format
+ */
+ ExpandedObjectHeader *eoh;
+ Size resultsize;
+
+ eoh = DatumGetEOHP(PointerGetDatum(attr));
+ resultsize = EOH_get_flat_size(eoh);
+ result = (struct varlena *) palloc(resultsize);
+ EOH_flatten_into(eoh, (void *) result, resultsize);
+ }
else
{
/*
*************** heap_tuple_untoast_attr(struct varlena *
*** 196,201 ****
--- 210,224 ----
attr = result;
}
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+ {
+ /*
+ * This is an expanded-object pointer --- get flat format
+ */
+ attr = heap_tuple_fetch_attr(attr);
+ /* flatteners are not allowed to produce compressed/short output */
+ Assert(!VARATT_IS_EXTENDED(attr));
+ }
else if (VARATT_IS_COMPRESSED(attr))
{
/*
*************** heap_tuple_untoast_attr_slice(struct var
*** 263,268 ****
--- 286,296 ----
return heap_tuple_untoast_attr_slice(redirect.pointer,
sliceoffset, slicelength);
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+ {
+ /* pass it off to heap_tuple_fetch_attr to flatten */
+ preslice = heap_tuple_fetch_attr(attr);
+ }
else
preslice = attr;
*************** toast_raw_datum_size(Datum value)
*** 344,349 ****
--- 372,381 ----
return toast_raw_datum_size(PointerGetDatum(toast_pointer.pointer));
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+ {
+ result = EOH_get_flat_size(DatumGetEOHP(value));
+ }
else if (VARATT_IS_COMPRESSED(attr))
{
/* here, va_rawsize is just the payload size */
*************** toast_datum_size(Datum value)
*** 400,405 ****
--- 432,441 ----
return toast_datum_size(PointerGetDatum(toast_pointer.pointer));
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+ {
+ result = EOH_get_flat_size(DatumGetEOHP(value));
+ }
else if (VARATT_IS_SHORT(attr))
{
result = VARSIZE_SHORT(attr);
diff --git a/src/backend/executor/execTuples.c b/src/backend/executor/execTuples.c
index 753754d..a05d8b1 100644
*** a/src/backend/executor/execTuples.c
--- b/src/backend/executor/execTuples.c
***************
*** 88,93 ****
--- 88,94 ----
#include "nodes/nodeFuncs.h"
#include "storage/bufmgr.h"
#include "utils/builtins.h"
+ #include "utils/expandeddatum.h"
#include "utils/lsyscache.h"
#include "utils/typcache.h"
*************** ExecCopySlot(TupleTableSlot *dstslot, Tu
*** 812,817 ****
--- 813,864 ----
return ExecStoreTuple(newTuple, dstslot, InvalidBuffer, true);
}
+ /* --------------------------------
+ * ExecMakeSlotContentsReadOnly
+ * Mark any R/W expanded datums in the slot as read-only.
+ *
+ * This is needed when a slot that might contain R/W datum references is to be
+ * used as input for general expression evaluation. Since the expression(s)
+ * might contain more than one Var referencing the same R/W datum, we could
+ * get wrong answers if functions acting on those Vars thought they could
+ * modify the expanded value in-place.
+ *
+ * For notational reasons, we return the same slot passed in.
+ * --------------------------------
+ */
+ TupleTableSlot *
+ ExecMakeSlotContentsReadOnly(TupleTableSlot *slot)
+ {
+ /*
+ * sanity checks
+ */
+ Assert(slot != NULL);
+ Assert(slot->tts_tupleDescriptor != NULL);
+ Assert(!slot->tts_isempty);
+
+ /*
+ * If the slot contains a physical tuple, it can't contain any expanded
+ * datums, because we flatten those when making a physical tuple. This
+ * might change later; but for now, we need do nothing unless the slot is
+ * virtual.
+ */
+ if (slot->tts_tuple == NULL)
+ {
+ Form_pg_attribute *att = slot->tts_tupleDescriptor->attrs;
+ int attnum;
+
+ for (attnum = 0; attnum < slot->tts_nvalid; attnum++)
+ {
+ slot->tts_values[attnum] =
+ MakeExpandedObjectReadOnly(slot->tts_values[attnum],
+ slot->tts_isnull[attnum],
+ att[attnum]->attlen);
+ }
+ }
+
+ return slot;
+ }
+
/* ----------------------------------------------------------------
* convenience initialization routines
diff --git a/src/backend/executor/nodeSubqueryscan.c b/src/backend/executor/nodeSubqueryscan.c
index 3f66e24..e5d1e54 100644
*** a/src/backend/executor/nodeSubqueryscan.c
--- b/src/backend/executor/nodeSubqueryscan.c
*************** SubqueryNext(SubqueryScanState *node)
*** 56,62 ****
--- 56,70 ----
* We just return the subplan's result slot, rather than expending extra
* cycles for ExecCopySlot(). (Our own ScanTupleSlot is used only for
* EvalPlanQual rechecks.)
+ *
+ * We do need to mark the slot contents read-only to prevent interference
+ * between different functions reading the same datum from the slot. It's
+ * a bit hokey to do this to the subplan's slot, but should be safe
+ * enough.
*/
+ if (!TupIsNull(slot))
+ slot = ExecMakeSlotContentsReadOnly(slot);
+
return slot;
}
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 4b86e91..daa9f69 100644
*** a/src/backend/executor/spi.c
--- b/src/backend/executor/spi.c
*************** SPI_pfree(void *pointer)
*** 1014,1019 ****
--- 1014,1040 ----
pfree(pointer);
}
+ Datum
+ SPI_datumTransfer(Datum value, bool typByVal, int typLen)
+ {
+ MemoryContext oldcxt = NULL;
+ Datum result;
+
+ if (_SPI_curid + 1 == _SPI_connected) /* connected */
+ {
+ if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
+ elog(ERROR, "SPI stack corrupted");
+ oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
+ }
+
+ result = datumTransfer(value, typByVal, typLen);
+
+ if (oldcxt)
+ MemoryContextSwitchTo(oldcxt);
+
+ return result;
+ }
+
void
SPI_freetuple(HeapTuple tuple)
{
diff --git a/src/backend/utils/adt/Makefile b/src/backend/utils/adt/Makefile
index 20e5ff1..d1ed33f 100644
*** a/src/backend/utils/adt/Makefile
--- b/src/backend/utils/adt/Makefile
*************** endif
*** 16,25 ****
endif
# keep this list arranged alphabetically or it gets to be a mess
! OBJS = acl.o arrayfuncs.o array_selfuncs.o array_typanalyze.o \
! array_userfuncs.o arrayutils.o ascii.o bool.o \
! cash.o char.o date.o datetime.o datum.o dbsize.o domains.o \
! encode.o enum.o float.o format_type.o formatting.o genfile.o \
geo_ops.o geo_selfuncs.o inet_cidr_ntop.o inet_net_pton.o int.o \
int8.o json.o jsonb.o jsonb_gin.o jsonb_op.o jsonb_util.o \
jsonfuncs.o like.o lockfuncs.o mac.o misc.o nabstime.o name.o \
--- 16,26 ----
endif
# keep this list arranged alphabetically or it gets to be a mess
! OBJS = acl.o arrayfuncs.o array_expanded.o array_selfuncs.o \
! array_typanalyze.o array_userfuncs.o arrayutils.o ascii.o \
! bool.o cash.o char.o date.o datetime.o datum.o dbsize.o domains.o \
! encode.o enum.o expandeddatum.o \
! float.o format_type.o formatting.o genfile.o \
geo_ops.o geo_selfuncs.o inet_cidr_ntop.o inet_net_pton.o int.o \
int8.o json.o jsonb.o jsonb_gin.o jsonb_op.o jsonb_util.o \
jsonfuncs.o like.o lockfuncs.o mac.o misc.o nabstime.o name.o \
diff --git a/src/backend/utils/adt/array_expanded.c b/src/backend/utils/adt/array_expanded.c
index ...d0ba8e6 .
*** a/src/backend/utils/adt/array_expanded.c
--- b/src/backend/utils/adt/array_expanded.c
***************
*** 0 ****
--- 1,1038 ----
+ /*-------------------------------------------------------------------------
+ *
+ * array_expanded.c
+ * Functions for manipulating expanded arrays.
+ *
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/array_expanded.c
+ *
+ *-------------------------------------------------------------------------
+ */
+ #include "postgres.h"
+
+ #include "access/tupmacs.h"
+ #include "utils/array.h"
+ #include "utils/builtins.h"
+ #include "utils/datum.h"
+ #include "utils/expandeddatum.h"
+ #include "utils/lsyscache.h"
+ #include "utils/memutils.h"
+
+
+ /*
+ * An expanded array is contained within a private memory context (as
+ * all expanded objects must be) and has a control structure as below.
+ *
+ * The expanded array might contain a regular "flat" array if that was the
+ * original input and we've not modified it significantly. Otherwise, the
+ * contents are represented by Datum/isnull arrays plus dimensionality and
+ * type information. We could also have both forms, if we've deconstructed
+ * the original array for access purposes but not yet changed it. For pass-
+ * by-reference element types, the Datums would point into the flat array in
+ * this situation. Once we start modifying array elements, new pass-by-ref
+ * elements are separately palloc'd within the memory context.
+ */
+ #define EA_MAGIC 689375833 /* ID for debugging crosschecks */
+
+ typedef struct ExpandedArrayHeader
+ {
+ /* Standard header for expanded objects */
+ ExpandedObjectHeader hdr;
+
+ /* Magic value identifying an expanded array (for debugging only) */
+ int ea_magic;
+
+ /* Dimensionality info (always valid) */
+ int ndims; /* # of dimensions */
+ int *dims; /* array dimensions */
+ int *lbound; /* index lower bounds for each dimension */
+
+ /* Element type info (always valid) */
+ Oid element_type; /* element type OID */
+ int16 typlen; /* needed info about element datatype */
+ bool typbyval;
+ char typalign;
+
+ /*
+ * If we have a Datum-array representation of the array, it's kept here;
+ * else dvalues/dnulls are NULL. The dvalues and dnulls arrays are always
+ * palloc'd within the object private context, but may change size from
+ * time to time. For pass-by-ref element types, dvalues entries might
+ * point either into the fstartptr..fendptr area, or to separately
+ * palloc'd chunks. Elements should always be fully detoasted, as they
+ * are in the standard flat representation.
+ *
+ * Even when dvalues is valid, dnulls can be NULL if there are no null
+ * elements.
+ */
+ Datum *dvalues; /* array of Datums */
+ bool *dnulls; /* array of is-null flags for Datums */
+ int dvalueslen; /* allocated length of above arrays */
+ int nelems; /* number of valid entries in above arrays */
+
+ /*
+ * flat_size is the current space requirement for the flat equivalent of
+ * the expanded array, if known; otherwise it's 0. We store this to make
+ * consecutive calls of get_flat_size cheap.
+ */
+ Size flat_size;
+
+ /*
+ * fvalue points to the flat representation if it is valid, else it is
+ * NULL. If we have or ever had a flat representation then
+ * fstartptr/fendptr point to the start and end+1 of its data area; this
+ * is so that we can tell which Datum pointers point into the flat
+ * representation rather than being pointers to separately palloc'd data.
+ */
+ ArrayType *fvalue; /* must be a fully detoasted array */
+ char *fstartptr; /* start of its data area */
+ char *fendptr; /* end+1 of its data area */
+ } ExpandedArrayHeader;
+
+ /* "Methods" required for an expanded object */
+ static Size EA_get_flat_size(ExpandedObjectHeader *eohptr);
+ static void EA_flatten_into(ExpandedObjectHeader *eohptr,
+ void *result, Size allocated_size);
+
+ static const ExpandedObjectMethods EA_methods =
+ {
+ EA_get_flat_size,
+ EA_flatten_into
+ };
+
+ /*
+ * Functions that can handle either a "flat" varlena array or an expanded
+ * array use this union to work with their input.
+ */
+ typedef union AnyArrayType
+ {
+ ArrayType flt;
+ ExpandedArrayHeader xpn;
+ } AnyArrayType;
+
+ /*
+ * Macros for working with AnyArrayType inputs. Beware multiple references!
+ */
+ #define AARR_NDIM(a) \
+ (VARATT_IS_EXPANDED_HEADER(a) ? (a)->xpn.ndims : ARR_NDIM(&(a)->flt))
+ #define AARR_HASNULL(a) \
+ (VARATT_IS_EXPANDED_HEADER(a) ? \
+ ((a)->xpn.dvalues != NULL ? (a)->xpn.dnulls != NULL : ARR_HASNULL((a)->xpn.fvalue)) : \
+ ARR_HASNULL(&(a)->flt))
+ #define AARR_ELEMTYPE(a) \
+ (VARATT_IS_EXPANDED_HEADER(a) ? (a)->xpn.element_type : ARR_ELEMTYPE(&(a)->flt))
+ #define AARR_DIMS(a) \
+ (VARATT_IS_EXPANDED_HEADER(a) ? (a)->xpn.dims : ARR_DIMS(&(a)->flt))
+ #define AARR_LBOUND(a) \
+ (VARATT_IS_EXPANDED_HEADER(a) ? (a)->xpn.lbound : ARR_LBOUND(&(a)->flt))
+
+
+ /*
+ * expand_array: convert an array Datum into an expanded array
+ *
+ * The expanded object will be a child of parentcontext.
+ *
+ * Caller can provide element type's representational data; we do that because
+ * caller is often in a position to cache it across repeated calls. If the
+ * caller can't do that, pass zeroes for elmlen/elmbyval/elmalign.
+ */
+ Datum
+ expand_array(Datum arraydatum, MemoryContext parentcontext,
+ int elmlen, bool elmbyval, char elmalign)
+ {
+ ArrayType *array;
+ ExpandedArrayHeader *eah;
+ MemoryContext objcxt;
+ MemoryContext oldcxt;
+
+ /* allocate private context for expanded object */
+ /* TODO: should we use some other memory context size parameters? */
+ objcxt = AllocSetContextCreate(parentcontext,
+ "expanded array",
+ ALLOCSET_DEFAULT_MINSIZE,
+ ALLOCSET_DEFAULT_INITSIZE,
+ ALLOCSET_DEFAULT_MAXSIZE);
+
+ /* set up expanded array header */
+ eah = (ExpandedArrayHeader *)
+ MemoryContextAlloc(objcxt, sizeof(ExpandedArrayHeader));
+
+ EOH_init_header(&eah->hdr, &EA_methods, objcxt);
+ eah->ea_magic = EA_MAGIC;
+
+ /*
+ * Detoast and copy original array into private context, as a flat array.
+ * We flatten it even if it's in expanded form; it's not clear that adding
+ * a special-case path for that would be worth the trouble.
+ *
+ * Note that this coding risks leaking some memory in the private context
+ * if we have to fetch data from a TOAST table; however, experimentation
+ * says that the leak is minimal. Doing it this way saves a copy step,
+ * which seems worthwhile, especially if the array is large enough to need
+ * external storage.
+ */
+ oldcxt = MemoryContextSwitchTo(objcxt);
+ array = DatumGetArrayTypePCopy(arraydatum);
+ MemoryContextSwitchTo(oldcxt);
+
+ eah->ndims = ARR_NDIM(array);
+ /* note these pointers point into the fvalue header! */
+ eah->dims = ARR_DIMS(array);
+ eah->lbound = ARR_LBOUND(array);
+
+ /* save array's element-type data for possible use later */
+ eah->element_type = ARR_ELEMTYPE(array);
+ if (elmlen)
+ {
+ /* Caller provided representational data */
+ eah->typlen = elmlen;
+ eah->typbyval = elmbyval;
+ eah->typalign = elmalign;
+ }
+ else
+ {
+ /* No, so look it up */
+ get_typlenbyvalalign(eah->element_type,
+ &eah->typlen,
+ &eah->typbyval,
+ &eah->typalign);
+ }
+
+ /* we don't make a deconstructed representation now */
+ eah->dvalues = NULL;
+ eah->dnulls = NULL;
+ eah->dvalueslen = 0;
+ eah->nelems = 0;
+ eah->flat_size = 0;
+
+ /* remember we have a flat representation */
+ eah->fvalue = array;
+ eah->fstartptr = ARR_DATA_PTR(array);
+ eah->fendptr = ((char *) array) + ARR_SIZE(array);
+
+ /* return a R/W pointer to the expanded array */
+ return PointerGetDatum(eah->hdr.eoh_rw_ptr);
+ }
+
+ /*
+ * construct_empty_expanded_array: make an empty expanded array
+ * given only type information. (elmlen etc can be zeroes.)
+ */
+ static ExpandedArrayHeader *
+ construct_empty_expanded_array(Oid element_type,
+ MemoryContext parentcontext,
+ int elmlen, bool elmbyval, char elmalign)
+ {
+ ArrayType *array = construct_empty_array(element_type);
+ Datum d;
+
+ d = expand_array(PointerGetDatum(array), parentcontext,
+ elmlen, elmbyval, elmalign);
+ return (ExpandedArrayHeader *) DatumGetEOHP(d);
+ }
+
+
+ /*
+ * get_flat_size method for expanded arrays
+ */
+ static Size
+ EA_get_flat_size(ExpandedObjectHeader *eohptr)
+ {
+ ExpandedArrayHeader *eah = (ExpandedArrayHeader *) eohptr;
+ int nelems;
+ int ndims;
+ Datum *dvalues;
+ bool *dnulls;
+ Size nbytes;
+ int i;
+
+ Assert(eah->ea_magic == EA_MAGIC);
+
+ /* Easy if we have a valid flattened value */
+ if (eah->fvalue)
+ return ARR_SIZE(eah->fvalue);
+
+ /* If we have a cached size value, believe that */
+ if (eah->flat_size)
+ return eah->flat_size;
+
+ /*
+ * Compute space needed by examining dvalues/dnulls. Note that the result
+ * array will have a nulls bitmap if dnulls isn't NULL, even if the array
+ * doesn't actually contain any nulls now.
+ */
+ nelems = eah->nelems;
+ ndims = eah->ndims;
+ Assert(nelems == ArrayGetNItems(ndims, eah->dims));
+ dvalues = eah->dvalues;
+ dnulls = eah->dnulls;
+ nbytes = 0;
+ for (i = 0; i < nelems; i++)
+ {
+ if (dnulls && dnulls[i])
+ continue;
+ nbytes = att_addlength_datum(nbytes, eah->typlen, dvalues[i]);
+ nbytes = att_align_nominal(nbytes, eah->typalign);
+ /* check for overflow of total request */
+ if (!AllocSizeIsValid(nbytes))
+ ereport(ERROR,
+ (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+ errmsg("array size exceeds the maximum allowed (%d)",
+ (int) MaxAllocSize)));
+ }
+
+ if (dnulls)
+ nbytes += ARR_OVERHEAD_WITHNULLS(ndims, nelems);
+ else
+ nbytes += ARR_OVERHEAD_NONULLS(ndims);
+
+ /* cache for next time */
+ eah->flat_size = nbytes;
+
+ return nbytes;
+ }
+
+ /*
+ * flatten_into method for expanded arrays
+ */
+ static void
+ EA_flatten_into(ExpandedObjectHeader *eohptr,
+ void *result, Size allocated_size)
+ {
+ ExpandedArrayHeader *eah = (ExpandedArrayHeader *) eohptr;
+ ArrayType *aresult = (ArrayType *) result;
+ int nelems;
+ int ndims;
+ int32 dataoffset;
+
+ Assert(eah->ea_magic == EA_MAGIC);
+
+ /* Easy if we have a valid flattened value */
+ if (eah->fvalue)
+ {
+ Assert(allocated_size == ARR_SIZE(eah->fvalue));
+ memcpy(result, eah->fvalue, allocated_size);
+ return;
+ }
+
+ /* Else allocation should match previous get_flat_size result */
+ Assert(allocated_size == eah->flat_size);
+
+ /* Fill result array from dvalues/dnulls */
+ nelems = eah->nelems;
+ ndims = eah->ndims;
+
+ if (eah->dnulls)
+ dataoffset = ARR_OVERHEAD_WITHNULLS(ndims, nelems);
+ else
+ dataoffset = 0; /* marker for no null bitmap */
+
+ /* We must ensure that any pad space is zero-filled */
+ memset(aresult, 0, allocated_size);
+
+ SET_VARSIZE(aresult, allocated_size);
+ aresult->ndim = ndims;
+ aresult->dataoffset = dataoffset;
+ aresult->elemtype = eah->element_type;
+ memcpy(ARR_DIMS(aresult), eah->dims, ndims * sizeof(int));
+ memcpy(ARR_LBOUND(aresult), eah->lbound, ndims * sizeof(int));
+
+ CopyArrayEls(aresult,
+ eah->dvalues, eah->dnulls, nelems,
+ eah->typlen, eah->typbyval, eah->typalign,
+ false);
+ }
+
+ /*
+ * Argument fetching support code
+ */
+
+ #ifdef NOT_YET_USED
+
+ /*
+ * DatumGetExpandedArray: get a writable expanded array from an input argument
+ */
+ static ExpandedArrayHeader *
+ DatumGetExpandedArray(Datum d)
+ {
+ ExpandedArrayHeader *eah;
+
+ /* If it's a writable expanded array already, just return it */
+ if (VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)))
+ {
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(d);
+ Assert(eah->ea_magic == EA_MAGIC);
+ return eah;
+ }
+
+ /*
+ * If it's a non-writable expanded array, copy it, extracting the element
+ * representational data to save a catalog lookup.
+ */
+ if (VARATT_IS_EXTERNAL_EXPANDED_RO(DatumGetPointer(d)))
+ {
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(d);
+ Assert(eah->ea_magic == EA_MAGIC);
+ d = expand_array(d, CurrentMemoryContext,
+ eah->typlen, eah->typbyval, eah->typalign);
+ return (ExpandedArrayHeader *) DatumGetEOHP(d);
+ }
+
+ /* Else expand the hard way */
+ d = expand_array(d, CurrentMemoryContext, 0, 0, 0);
+ return (ExpandedArrayHeader *) DatumGetEOHP(d);
+ }
+
+ #define PG_GETARG_EXPANDED_ARRAY(n) DatumGetExpandedArray(PG_GETARG_DATUM(n))
+
+ #endif
+
+ /*
+ * As above, when caller has the ability to cache element type info
+ */
+ static ExpandedArrayHeader *
+ DatumGetExpandedArrayX(Datum d,
+ int elmlen, bool elmbyval, char elmalign)
+ {
+ ExpandedArrayHeader *eah;
+
+ /* If it's a writable expanded array already, just return it */
+ if (VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)))
+ {
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(d);
+ Assert(eah->ea_magic == EA_MAGIC);
+ Assert(eah->typlen == elmlen);
+ Assert(eah->typbyval == elmbyval);
+ Assert(eah->typalign == elmalign);
+ return eah;
+ }
+
+ /* Else expand using caller's data */
+ d = expand_array(d, CurrentMemoryContext, elmlen, elmbyval, elmalign);
+ return (ExpandedArrayHeader *) DatumGetEOHP(d);
+ }
+
+ #define PG_GETARG_EXPANDED_ARRAYX(n, elmlen, elmbyval, elmalign) \
+ DatumGetExpandedArrayX(PG_GETARG_DATUM(n), elmlen, elmbyval, elmalign)
+
+ /*
+ * DatumGetAnyArray: return either an expanded array or a detoasted varlena
+ * array. The result must not be modified in-place.
+ */
+ static AnyArrayType *
+ DatumGetAnyArray(Datum d)
+ {
+ ExpandedArrayHeader *eah;
+
+ /*
+ * If it's an expanded array (RW or RO), return the header pointer.
+ */
+ if (VARATT_IS_EXTERNAL_EXPANDED(DatumGetPointer(d)))
+ {
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(d);
+ Assert(eah->ea_magic == EA_MAGIC);
+ return (AnyArrayType *) eah;
+ }
+
+ /* Else do regular detoasting as needed */
+ return (AnyArrayType *) PG_DETOAST_DATUM(d);
+ }
+
+ #define PG_GETARG_ANY_ARRAY(n) DatumGetAnyArray(PG_GETARG_DATUM(n))
+
+ /*
+ * Create the Datum/isnull representation if we didn't do so previously
+ */
+ static void
+ deconstruct_expanded_array(ExpandedArrayHeader *eah)
+ {
+ if (eah->dvalues == NULL)
+ {
+ MemoryContext oldcxt = MemoryContextSwitchTo(eah->hdr.eoh_context);
+ Datum *dvalues;
+ bool *dnulls;
+ int nelems;
+
+ dnulls = NULL;
+ deconstruct_array(eah->fvalue,
+ eah->element_type,
+ eah->typlen, eah->typbyval, eah->typalign,
+ &dvalues,
+ ARR_HASNULL(eah->fvalue) ? &dnulls : NULL,
+ &nelems);
+
+ /*
+ * Update header only after successful completion of this step. If
+ * deconstruct_array fails partway through, worst consequence is some
+ * leaked memory in the object's context. If the caller fails at a
+ * later point, that's fine, since the deconstructed representation is
+ * valid anyhow.
+ */
+ eah->dvalues = dvalues;
+ eah->dnulls = dnulls;
+ eah->dvalueslen = eah->nelems = nelems;
+ MemoryContextSwitchTo(oldcxt);
+ }
+ }
+
+ /*
+ * Equivalent of array_ref() for an expanded array
+ */
+ Datum
+ array_ref_expanded(Datum arraydatum,
+ int nSubscripts, int *indx,
+ int arraytyplen,
+ int elmlen, bool elmbyval, char elmalign,
+ bool *isNull)
+ {
+ ExpandedArrayHeader *eah;
+ int i,
+ ndim,
+ *dim,
+ *lb,
+ offset;
+ Datum *dvalues;
+ bool *dnulls;
+
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(arraydatum);
+ Assert(eah->ea_magic == EA_MAGIC);
+
+ /* sanity-check caller's state; we don't use the passed data otherwise */
+ Assert(arraytyplen == -1);
+ Assert(elmlen == eah->typlen);
+ Assert(elmbyval == eah->typbyval);
+ Assert(elmalign == eah->typalign);
+
+ ndim = eah->ndims;
+ dim = eah->dims;
+ lb = eah->lbound;
+
+ /*
+ * Return NULL for invalid subscript
+ */
+ if (ndim != nSubscripts || ndim <= 0 || ndim > MAXDIM)
+ {
+ *isNull = true;
+ return (Datum) 0;
+ }
+ for (i = 0; i < ndim; i++)
+ {
+ if (indx[i] < lb[i] || indx[i] >= (dim[i] + lb[i]))
+ {
+ *isNull = true;
+ return (Datum) 0;
+ }
+ }
+
+ /*
+ * Calculate the element number
+ */
+ offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+
+ /*
+ * Deconstruct array if we didn't already. Note that we apply this even
+ * if the input is nominally read-only: it should be safe enough.
+ */
+ deconstruct_expanded_array(eah);
+
+ dvalues = eah->dvalues;
+ dnulls = eah->dnulls;
+
+ /*
+ * Check for NULL array element
+ */
+ if (dnulls && dnulls[offset])
+ {
+ *isNull = true;
+ return (Datum) 0;
+ }
+
+ /*
+ * OK, get the element. It's OK to return a pass-by-ref value as a
+ * pointer into the expanded array, for the same reason that array_ref can
+ * return a pointer into flat arrays: the value is assumed not to change
+ * for as long as the Datum reference can exist.
+ */
+ *isNull = false;
+ return dvalues[offset];
+ }
+
+ /*
+ * Equivalent of array_set() for an expanded array
+ *
+ * array_set took care of detoasting dataValue, the rest is up to us
+ *
+ * Note: as with any operation on a read/write expanded object, we must
+ * take pains not to leave the object in a corrupt state if we fail partway
+ * through.
+ */
+ Datum
+ array_set_expanded(Datum arraydatum,
+ int nSubscripts, int *indx,
+ Datum dataValue, bool isNull,
+ int arraytyplen,
+ int elmlen, bool elmbyval, char elmalign)
+ {
+ ExpandedArrayHeader *eah;
+ Datum *dvalues;
+ bool *dnulls;
+ int i,
+ ndim,
+ dim[MAXDIM],
+ lb[MAXDIM],
+ offset;
+ bool dimschanged,
+ newhasnulls;
+ int addedbefore,
+ addedafter;
+ char *oldValue;
+
+ eah = (ExpandedArrayHeader *) DatumGetEOHP(arraydatum);
+ Assert(eah->ea_magic == EA_MAGIC);
+
+ /* if this fails, we shouldn't be modifying this array in-place */
+ Assert(VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(arraydatum)));
+
+ /* sanity-check caller's state; we don't use the passed data otherwise */
+ Assert(arraytyplen == -1);
+ Assert(elmlen == eah->typlen);
+ Assert(elmbyval == eah->typbyval);
+ Assert(elmalign == eah->typalign);
+
+ /*
+ * Copy dimension info into local storage. This allows us to modify the
+ * dimensions if needed, while not messing up the expanded value if we
+ * fail partway through.
+ */
+ ndim = eah->ndims;
+ Assert(ndim >= 0 && ndim <= MAXDIM);
+ memcpy(dim, eah->dims, ndim * sizeof(int));
+ memcpy(lb, eah->lbound, ndim * sizeof(int));
+ dimschanged = false;
+
+ /*
+ * if number of dims is zero, i.e. an empty array, create an array with
+ * nSubscripts dimensions, and set the lower bounds to the supplied
+ * subscripts.
+ */
+ if (ndim == 0)
+ {
+ /*
+ * Allocate adequate space for new dimension info. This is harmless
+ * if we fail later.
+ */
+ Assert(nSubscripts > 0 && nSubscripts <= MAXDIM);
+ eah->dims = (int *) MemoryContextAllocZero(eah->hdr.eoh_context,
+ nSubscripts * sizeof(int));
+ eah->lbound = (int *) MemoryContextAllocZero(eah->hdr.eoh_context,
+ nSubscripts * sizeof(int));
+
+ /* Update local copies of dimension info */
+ ndim = nSubscripts;
+ for (i = 0; i < nSubscripts; i++)
+ {
+ dim[i] = 0;
+ lb[i] = indx[i];
+ }
+ dimschanged = true;
+ }
+ else if (ndim != nSubscripts)
+ ereport(ERROR,
+ (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+ errmsg("wrong number of array subscripts")));
+
+ /*
+ * Deconstruct array if we didn't already. (Someday maybe add a special
+ * case path for fixed-length, no-nulls cases, where we can overwrite an
+ * element in place without ever deconstructing. But today is not that
+ * day.)
+ */
+ deconstruct_expanded_array(eah);
+
+ /*
+ * Copy new element into array's context, if needed (we assume it's
+ * already detoasted, so no junk should be created). If we fail further
+ * down, this memory is leaked, but that's reasonably harmless.
+ */
+ if (!eah->typbyval && !isNull)
+ {
+ MemoryContext oldcxt = MemoryContextSwitchTo(eah->hdr.eoh_context);
+
+ dataValue = datumCopy(dataValue, false, eah->typlen);
+ MemoryContextSwitchTo(oldcxt);
+ }
+
+ dvalues = eah->dvalues;
+ dnulls = eah->dnulls;
+
+ newhasnulls = ((dnulls != NULL) || isNull);
+ addedbefore = addedafter = 0;
+
+ /*
+ * Check subscripts (this logic matches original array_set)
+ */
+ if (ndim == 1)
+ {
+ if (indx[0] < lb[0])
+ {
+ addedbefore = lb[0] - indx[0];
+ dim[0] += addedbefore;
+ lb[0] = indx[0];
+ dimschanged = true;
+ if (addedbefore > 1)
+ newhasnulls = true; /* will insert nulls */
+ }
+ if (indx[0] >= (dim[0] + lb[0]))
+ {
+ addedafter = indx[0] - (dim[0] + lb[0]) + 1;
+ dim[0] += addedafter;
+ dimschanged = true;
+ if (addedafter > 1)
+ newhasnulls = true; /* will insert nulls */
+ }
+ }
+ else
+ {
+ /*
+ * XXX currently we do not support extending multi-dimensional arrays
+ * during assignment
+ */
+ for (i = 0; i < ndim; i++)
+ {
+ if (indx[i] < lb[i] ||
+ indx[i] >= (dim[i] + lb[i]))
+ ereport(ERROR,
+ (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+ errmsg("array subscript out of range")));
+ }
+ }
+
+ /* Now we can calculate linear offset of target item in array */
+ offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+
+ /* Physically enlarge existing dvalues/dnulls arrays if needed */
+ if (dim[0] > eah->dvalueslen)
+ {
+ /* We want some extra space if we're enlarging */
+ int newlen = dim[0] + dim[0] / 8;
+
+ eah->dvalues = dvalues = (Datum *)
+ repalloc(dvalues, newlen * sizeof(Datum));
+ if (dnulls)
+ eah->dnulls = dnulls = (bool *)
+ repalloc(dnulls, newlen * sizeof(bool));
+ eah->dvalueslen = newlen;
+ }
+
+ /*
+ * If we need a nulls bitmap and don't already have one, create it, being
+ * sure to mark all existing entries as not null.
+ */
+ if (newhasnulls && dnulls == NULL)
+ eah->dnulls = dnulls = (bool *)
+ MemoryContextAllocZero(eah->hdr.eoh_context,
+ eah->dvalueslen * sizeof(bool));
+
+ /*
+ * We now have all the needed space allocated, so we're ready to make
+ * irreversible changes. Be very wary of allowing failure below here.
+ */
+
+ /* Flattened value will no longer represent array accurately */
+ eah->fvalue = NULL;
+ /* And we don't know the flattened size either */
+ eah->flat_size = 0;
+
+ /* Update dimensionality info if needed */
+ if (dimschanged)
+ {
+ eah->ndims = ndim;
+ memcpy(eah->dims, dim, ndim * sizeof(int));
+ memcpy(eah->lbound, lb, ndim * sizeof(int));
+ }
+
+ /* Reposition items if needed, and fill addedbefore items with nulls */
+ if (addedbefore > 0)
+ {
+ memmove(dvalues + addedbefore, dvalues, eah->nelems * sizeof(Datum));
+ for (i = 0; i < addedbefore; i++)
+ dvalues[i] = (Datum) 0;
+ if (dnulls)
+ {
+ memmove(dnulls + addedbefore, dnulls, eah->nelems * sizeof(bool));
+ for (i = 0; i < addedbefore; i++)
+ dnulls[i] = true;
+ }
+ eah->nelems += addedbefore;
+ }
+
+ /* fill addedafter items with nulls */
+ if (addedafter > 0)
+ {
+ for (i = 0; i < addedafter; i++)
+ dvalues[eah->nelems + i] = (Datum) 0;
+ if (dnulls)
+ {
+ for (i = 0; i < addedafter; i++)
+ dnulls[eah->nelems + i] = true;
+ }
+ eah->nelems += addedafter;
+ }
+
+ /* Grab old element value for pfree'ing, if needed. */
+ if (!eah->typbyval && (dnulls == NULL || !dnulls[offset]))
+ oldValue = (char *) DatumGetPointer(dvalues[offset]);
+ else
+ oldValue = NULL;
+
+ /* And finally we can insert the new element. */
+ dvalues[offset] = dataValue;
+ if (dnulls)
+ dnulls[offset] = isNull;
+
+ /*
+ * Free old element if needed; this keeps repeated element replacements
+ * from bloating the array's storage. If the pfree somehow fails, it
+ * won't corrupt the array.
+ */
+ if (oldValue)
+ {
+ /* Don't try to pfree a part of the original flat array */
+ if (oldValue < eah->fstartptr || oldValue >= eah->fendptr)
+ pfree(oldValue);
+ }
+
+ /* Done, return standard TOAST pointer for object */
+ return PointerGetDatum(eah->hdr.eoh_rw_ptr);
+ }
+
+ /*
+ * Reimplementation of array_push for expanded arrays
+ */
+ typedef struct ArrayPushState
+ {
+ Oid arg0_typeid;
+ Oid arg1_typeid;
+ bool array_on_left;
+ Oid element_type;
+ int16 typlen;
+ bool typbyval;
+ char typalign;
+ } ArrayPushState;
+
+ Datum
+ array_push_expanded(PG_FUNCTION_ARGS)
+ {
+ ExpandedArrayHeader *eah;
+ Datum newelem;
+ bool isNull;
+ int *dimv,
+ *lb;
+ ArrayType *result;
+ int indx;
+ int lb0;
+ Oid element_type;
+ int16 typlen;
+ bool typbyval;
+ char typalign;
+ Oid arg0_typeid = get_fn_expr_argtype(fcinfo->flinfo, 0);
+ Oid arg1_typeid = get_fn_expr_argtype(fcinfo->flinfo, 1);
+ ArrayPushState *my_extra;
+
+ if (arg0_typeid == InvalidOid || arg1_typeid == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine input data types")));
+
+ /*
+ * We arrange to look up info about element type only once per series of
+ * calls, assuming the element type doesn't change underneath us.
+ */
+ my_extra = (ArrayPushState *) fcinfo->flinfo->fn_extra;
+ if (my_extra == NULL)
+ {
+ fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+ sizeof(ArrayPushState));
+ my_extra = (ArrayPushState *) fcinfo->flinfo->fn_extra;
+ my_extra->arg0_typeid = InvalidOid;
+ }
+
+ if (my_extra->arg0_typeid != arg0_typeid ||
+ my_extra->arg1_typeid != arg1_typeid)
+ {
+ /* Determine which input is the array */
+ Oid arg0_elemid = get_element_type(arg0_typeid);
+ Oid arg1_elemid = get_element_type(arg1_typeid);
+
+ if (arg0_elemid != InvalidOid)
+ {
+ my_extra->array_on_left = true;
+ element_type = arg0_elemid;
+ }
+ else if (arg1_elemid != InvalidOid)
+ {
+ my_extra->array_on_left = false;
+ element_type = arg1_elemid;
+ }
+ else
+ {
+ /* Shouldn't get here given proper type checking in parser */
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("neither input type is an array")));
+ PG_RETURN_NULL(); /* keep compiler quiet */
+ }
+
+ my_extra->arg0_typeid = arg0_typeid;
+ my_extra->arg1_typeid = arg1_typeid;
+
+ /* Get info about element type */
+ get_typlenbyvalalign(element_type,
+ &my_extra->typlen,
+ &my_extra->typbyval,
+ &my_extra->typalign);
+ my_extra->element_type = element_type;
+ }
+
+ element_type = my_extra->element_type;
+ typlen = my_extra->typlen;
+ typbyval = my_extra->typbyval;
+ typalign = my_extra->typalign;
+
+ /*
+ * Now we can fetch the arguments, using cached type info if needed
+ */
+ if (my_extra->array_on_left)
+ {
+ if (PG_ARGISNULL(0))
+ eah = construct_empty_expanded_array(element_type,
+ CurrentMemoryContext,
+ typlen, typbyval, typalign);
+ else
+ eah = PG_GETARG_EXPANDED_ARRAYX(0, typlen, typbyval, typalign);
+ isNull = PG_ARGISNULL(1);
+ if (isNull)
+ newelem = (Datum) 0;
+ else
+ newelem = PG_GETARG_DATUM(1);
+ }
+ else
+ {
+ if (PG_ARGISNULL(1))
+ eah = construct_empty_expanded_array(element_type,
+ CurrentMemoryContext,
+ typlen, typbyval, typalign);
+ else
+ eah = PG_GETARG_EXPANDED_ARRAYX(1, typlen, typbyval, typalign);
+ isNull = PG_ARGISNULL(0);
+ if (isNull)
+ newelem = (Datum) 0;
+ else
+ newelem = PG_GETARG_DATUM(0);
+ }
+
+ Assert(element_type == eah->element_type);
+
+ /*
+ * Perform push (this logic is basically unchanged from original)
+ */
+ if (eah->ndims == 1)
+ {
+ lb = eah->lbound;
+ dimv = eah->dims;
+
+ if (my_extra->array_on_left)
+ {
+ /* append newelem */
+ int ub = dimv[0] + lb[0] - 1;
+
+ indx = ub + 1;
+ /* overflow? */
+ if (indx < ub)
+ ereport(ERROR,
+ (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+ errmsg("integer out of range")));
+ }
+ else
+ {
+ /* prepend newelem */
+ indx = lb[0] - 1;
+ /* overflow? */
+ if (indx > lb[0])
+ ereport(ERROR,
+ (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+ errmsg("integer out of range")));
+ }
+ lb0 = lb[0];
+ }
+ else if (eah->ndims == 0)
+ {
+ indx = 1;
+ lb0 = 1;
+ }
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_EXCEPTION),
+ errmsg("argument must be empty or one-dimensional array")));
+
+ result = array_set((ArrayType *) eah->hdr.eoh_rw_ptr,
+ 1, &indx, newelem, isNull,
+ -1, typlen, typbyval, typalign);
+
+ Assert(result == (ArrayType *) eah->hdr.eoh_rw_ptr);
+
+ /*
+ * Readjust result's LB to match the input's. We need do nothing in the
+ * append case, but it's the simplest way to implement the prepend case.
+ */
+ if (eah->ndims == 1 && !my_extra->array_on_left)
+ {
+ /* This is ok whether we've deconstructed or not */
+ eah->lbound[0] = lb0;
+ }
+
+ PG_RETURN_POINTER(result);
+ }
+
+ /*
+ * array_dims :
+ * returns the dimensions of the array pointed to by "v", as a "text"
+ *
+ * This is here as an example of handling either flat or expanded inputs.
+ */
+ Datum
+ array_dims_expanded(PG_FUNCTION_ARGS)
+ {
+ AnyArrayType *v = PG_GETARG_ANY_ARRAY(0);
+ char *p;
+ int i;
+ int *dimv,
+ *lb;
+
+ /*
+ * 33 since we assume 15 digits per number + ':' +'[]'
+ *
+ * +1 for trailing null
+ */
+ char buf[MAXDIM * 33 + 1];
+
+ /* Sanity check: does it look like an array at all? */
+ if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+ PG_RETURN_NULL();
+
+ dimv = AARR_DIMS(v);
+ lb = AARR_LBOUND(v);
+
+ p = buf;
+ for (i = 0; i < AARR_NDIM(v); i++)
+ {
+ sprintf(p, "[%d:%d]", lb[i], dimv[i] + lb[i] - 1);
+ p += strlen(p);
+ }
+
+ PG_RETURN_TEXT_P(cstring_to_text(buf));
+ }
diff --git a/src/backend/utils/adt/array_userfuncs.c b/src/backend/utils/adt/array_userfuncs.c
index 600646e..7eee40c 100644
*** a/src/backend/utils/adt/array_userfuncs.c
--- b/src/backend/utils/adt/array_userfuncs.c
***************
*** 25,30 ****
--- 25,33 ----
Datum
array_push(PG_FUNCTION_ARGS)
{
+ #if 1
+ return array_push_expanded(fcinfo);
+ #else
ArrayType *v;
Datum newelem;
bool isNull;
*************** array_push(PG_FUNCTION_ARGS)
*** 157,162 ****
--- 160,166 ----
ARR_LBOUND(result)[0] = ARR_LBOUND(v)[0];
PG_RETURN_ARRAYTYPE_P(result);
+ #endif
}
/*-----------------------------------------------------------------------------
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 5591b46..3994843 100644
*** a/src/backend/utils/adt/arrayfuncs.c
--- b/src/backend/utils/adt/arrayfuncs.c
***************
*** 27,32 ****
--- 27,33 ----
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/datum.h"
+ #include "utils/expandeddatum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/typcache.h"
*************** static void ReadArrayBinary(StringInfo b
*** 93,102 ****
int typlen, bool typbyval, char typalign,
Datum *values, bool *nulls,
bool *hasnulls, int32 *nbytes);
- static void CopyArrayEls(ArrayType *array,
- Datum *values, bool *nulls, int nitems,
- int typlen, bool typbyval, char typalign,
- bool freedata);
static bool array_get_isnull(const bits8 *nullbitmap, int offset);
static void array_set_isnull(bits8 *nullbitmap, int offset, bool isNull);
static Datum ArrayCast(char *value, bool byval, int len);
--- 94,99 ----
*************** ReadArrayStr(char *arrayStr,
*** 939,945 ****
* the values are not toasted. (Doing it here doesn't work since the
* caller has already allocated space for the array...)
*/
! static void
CopyArrayEls(ArrayType *array,
Datum *values,
bool *nulls,
--- 936,942 ----
* the values are not toasted. (Doing it here doesn't work since the
* caller has already allocated space for the array...)
*/
! void
CopyArrayEls(ArrayType *array,
Datum *values,
bool *nulls,
*************** array_ndims(PG_FUNCTION_ARGS)
*** 1666,1671 ****
--- 1663,1671 ----
Datum
array_dims(PG_FUNCTION_ARGS)
{
+ #if 1
+ return array_dims_expanded(fcinfo);
+ #else
ArrayType *v = PG_GETARG_ARRAYTYPE_P(0);
char *p;
int i;
*************** array_dims(PG_FUNCTION_ARGS)
*** 1694,1699 ****
--- 1694,1700 ----
}
PG_RETURN_TEXT_P(cstring_to_text(buf));
+ #endif
}
/*
*************** array_ref(ArrayType *array,
*** 1849,1854 ****
--- 1850,1867 ----
arraydataptr = (char *) array;
arraynullsptr = NULL;
}
+ else if (VARATT_IS_EXTERNAL_EXPANDED(array))
+ {
+ /* hand off to array_expanded.c */
+ return array_ref_expanded(PointerGetDatum(array),
+ nSubscripts,
+ indx,
+ arraytyplen,
+ elmlen,
+ elmbyval,
+ elmalign,
+ isNull);
+ }
else
{
/* detoast input array if necessary */
*************** array_set(ArrayType *array,
*** 2161,2166 ****
--- 2174,2202 ----
if (elmlen == -1 && !isNull)
dataValue = PointerGetDatum(PG_DETOAST_DATUM(dataValue));
+ /* if array is in expanded form, hand off to array_expanded.c */
+ if (VARATT_IS_EXTERNAL_EXPANDED(array))
+ {
+ /* Convert to R/W form if not that already */
+ if (!VARATT_IS_EXTERNAL_EXPANDED_RW(array))
+ {
+ array = (ArrayType *) DatumGetPointer(
+ expand_array(PointerGetDatum(array), CurrentMemoryContext,
+ elmlen, elmbyval, elmalign));
+ }
+
+ return (ArrayType *) DatumGetPointer(
+ array_set_expanded(PointerGetDatum(array),
+ nSubscripts,
+ indx,
+ dataValue,
+ isNull,
+ arraytyplen,
+ elmlen,
+ elmbyval,
+ elmalign));
+ }
+
/* detoast input array if necessary */
array = DatumGetArrayTypeP(PointerGetDatum(array));
diff --git a/src/backend/utils/adt/datum.c b/src/backend/utils/adt/datum.c
index 014eca5..e8af030 100644
*** a/src/backend/utils/adt/datum.c
--- b/src/backend/utils/adt/datum.c
***************
*** 12,19 ****
*
*-------------------------------------------------------------------------
*/
/*
! * In the implementation of the next routines we assume the following:
*
* A) if a type is "byVal" then all the information is stored in the
* Datum itself (i.e. no pointers involved!). In this case the
--- 12,20 ----
*
*-------------------------------------------------------------------------
*/
+
/*
! * In the implementation of these routines we assume the following:
*
* A) if a type is "byVal" then all the information is stored in the
* Datum itself (i.e. no pointers involved!). In this case the
***************
*** 34,44 ****
--- 35,49 ----
*
* Note that we do not treat "toasted" datums specially; therefore what
* will be copied or compared is the compressed data or toast reference.
+ * An exception is made for datumCopy() of an expanded object, however,
+ * because most callers expect to get a simple contiguous (and pfree'able)
+ * result from datumCopy(). See also datumTransfer().
*/
#include "postgres.h"
#include "utils/datum.h"
+ #include "utils/expandeddatum.h"
/*-------------------------------------------------------------------------
***************
*** 46,51 ****
--- 51,57 ----
*
* Find the "real" size of a datum, given the datum value,
* whether it is a "by value", and the declared type length.
+ * (For TOAST pointer datums, this is the size of the pointer datum.)
*
* This is essentially an out-of-line version of the att_addlength_datum()
* macro in access/tupmacs.h. We do a tad more error checking though.
*************** datumGetSize(Datum value, bool typByVal,
*** 106,114 ****
/*-------------------------------------------------------------------------
* datumCopy
*
! * make a copy of a datum
*
* If the datatype is pass-by-reference, memory is obtained with palloc().
*-------------------------------------------------------------------------
*/
Datum
--- 112,127 ----
/*-------------------------------------------------------------------------
* datumCopy
*
! * Make a copy of a non-NULL datum.
*
* If the datatype is pass-by-reference, memory is obtained with palloc().
+ *
+ * If the value is a reference to an expanded object, we flatten into memory
+ * obtained with palloc(). We need to copy because one of the main uses of
+ * this function is to copy a datum out of a transient memory context that's
+ * about to be destroyed, and the expanded object is probably in a child
+ * context that will also go away. Moreover, many callers assume that the
+ * result is a single pfree-able chunk.
*-------------------------------------------------------------------------
*/
Datum
*************** datumCopy(Datum value, bool typByVal, in
*** 118,161 ****
if (typByVal)
res = value;
else
{
Size realSize;
! char *s;
!
! if (DatumGetPointer(value) == NULL)
! return PointerGetDatum(NULL);
realSize = datumGetSize(value, typByVal, typLen);
! s = (char *) palloc(realSize);
! memcpy(s, DatumGetPointer(value), realSize);
! res = PointerGetDatum(s);
}
return res;
}
/*-------------------------------------------------------------------------
! * datumFree
*
! * Free the space occupied by a datum CREATED BY "datumCopy"
*
! * NOTE: DO NOT USE THIS ROUTINE with datums returned by heap_getattr() etc.
! * ONLY datums created by "datumCopy" can be freed!
*-------------------------------------------------------------------------
*/
! #ifdef NOT_USED
! void
! datumFree(Datum value, bool typByVal, int typLen)
{
! if (!typByVal)
! {
! Pointer s = DatumGetPointer(value);
!
! pfree(s);
! }
}
- #endif
/*-------------------------------------------------------------------------
* datumIsEqual
--- 131,201 ----
if (typByVal)
res = value;
+ else if (typLen == -1)
+ {
+ /* It is a varlena datatype */
+ struct varlena *vl = (struct varlena *) DatumGetPointer(value);
+
+ if (VARATT_IS_EXTERNAL_EXPANDED(vl))
+ {
+ /* Flatten into the caller's memory context */
+ ExpandedObjectHeader *eoh = DatumGetEOHP(value);
+ Size resultsize;
+ char *resultptr;
+
+ resultsize = EOH_get_flat_size(eoh);
+ resultptr = (char *) palloc(resultsize);
+ EOH_flatten_into(eoh, (void *) resultptr, resultsize);
+ res = PointerGetDatum(resultptr);
+ }
+ else
+ {
+ /* Otherwise, just copy the varlena datum verbatim */
+ Size realSize;
+ char *resultptr;
+
+ realSize = (Size) VARSIZE_ANY(vl);
+ resultptr = (char *) palloc(realSize);
+ memcpy(resultptr, vl, realSize);
+ res = PointerGetDatum(resultptr);
+ }
+ }
else
{
+ /* Pass by reference, but not varlena, so not toasted */
Size realSize;
! char *resultptr;
realSize = datumGetSize(value, typByVal, typLen);
! resultptr = (char *) palloc(realSize);
! memcpy(resultptr, DatumGetPointer(value), realSize);
! res = PointerGetDatum(resultptr);
}
return res;
}
/*-------------------------------------------------------------------------
! * datumTransfer
*
! * Transfer a non-NULL datum into the current memory context.
*
! * This is equivalent to datumCopy() except when the datum is a read-write
! * pointer to an expanded object. In that case we merely reparent the object
! * into the current context, and return its standard R/W pointer (in case the
! * given one is a transient pointer of shorter lifespan).
*-------------------------------------------------------------------------
*/
! Datum
! datumTransfer(Datum value, bool typByVal, int typLen)
{
! if (!typByVal && typLen == -1 &&
! VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(value)))
! value = TransferExpandedObject(value, CurrentMemoryContext);
! else
! value = datumCopy(value, typByVal, typLen);
! return value;
}
/*-------------------------------------------------------------------------
* datumIsEqual
diff --git a/src/backend/utils/adt/expandeddatum.c b/src/backend/utils/adt/expandeddatum.c
index ...d43f437 .
*** a/src/backend/utils/adt/expandeddatum.c
--- b/src/backend/utils/adt/expandeddatum.c
***************
*** 0 ****
--- 1,162 ----
+ /*-------------------------------------------------------------------------
+ *
+ * expandeddatum.c
+ * Support functions for "expanded" value representations.
+ *
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/expandeddatum.c
+ *
+ *-------------------------------------------------------------------------
+ */
+ #include "postgres.h"
+
+ #include "utils/expandeddatum.h"
+ #include "utils/memutils.h"
+
+ /*
+ * DatumGetEOHP
+ *
+ * Given a Datum that is an expanded-object reference, extract the pointer.
+ *
+ * This is a bit tedious since the pointer may not be properly aligned;
+ * compare VARATT_EXTERNAL_GET_POINTER().
+ */
+ ExpandedObjectHeader *
+ DatumGetEOHP(Datum d)
+ {
+ varattrib_1b_e *datum = (varattrib_1b_e *) DatumGetPointer(d);
+ varatt_expanded ptr;
+
+ Assert(VARATT_IS_EXTERNAL_EXPANDED(datum));
+ memcpy(&ptr, VARDATA_EXTERNAL(datum), sizeof(ptr));
+ return ptr.eohptr;
+ }
+
+ /*
+ * EOH_init_header
+ *
+ * Initialize the common header of an expanded object.
+ *
+ * The main thing this encapsulates is initializing the TOAST pointers.
+ */
+ void
+ EOH_init_header(ExpandedObjectHeader *eohptr,
+ const ExpandedObjectMethods *methods,
+ MemoryContext obj_context)
+ {
+ varatt_expanded ptr;
+
+ eohptr->vl_len_ = EOH_HEADER_MAGIC;
+ eohptr->eoh_methods = methods;
+ eohptr->eoh_context = obj_context;
+
+ ptr.eohptr = eohptr;
+
+ SET_VARTAG_EXTERNAL(eohptr->eoh_rw_ptr, VARTAG_EXPANDED_RW);
+ memcpy(VARDATA_EXTERNAL(eohptr->eoh_rw_ptr), &ptr, sizeof(ptr));
+
+ SET_VARTAG_EXTERNAL(eohptr->eoh_ro_ptr, VARTAG_EXPANDED_RO);
+ memcpy(VARDATA_EXTERNAL(eohptr->eoh_ro_ptr), &ptr, sizeof(ptr));
+ }
+
+ /*
+ * EOH_get_flat_size
+ * EOH_flatten_into
+ *
+ * Convenience functions for invoking the "methods" of an expanded object.
+ */
+
+ Size
+ EOH_get_flat_size(ExpandedObjectHeader *eohptr)
+ {
+ return (*eohptr->eoh_methods->get_flat_size) (eohptr);
+ }
+
+ void
+ EOH_flatten_into(ExpandedObjectHeader *eohptr,
+ void *result, Size allocated_size)
+ {
+ (*eohptr->eoh_methods->flatten_into) (eohptr, result, allocated_size);
+ }
+
+ /*
+ * Does the Datum represent a writable expanded object?
+ */
+ bool
+ DatumIsReadWriteExpandedObject(Datum d, bool isnull, int16 typlen)
+ {
+ /* Reject if it's NULL or not a varlena type */
+ if (isnull || typlen != -1)
+ return false;
+
+ /* Reject if not a read-write expanded-object pointer */
+ if (!VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)))
+ return false;
+
+ return true;
+ }
+
+ /*
+ * If the Datum represents a R/W expanded object, change it to R/O.
+ * Otherwise return the original Datum.
+ */
+ Datum
+ MakeExpandedObjectReadOnly(Datum d, bool isnull, int16 typlen)
+ {
+ ExpandedObjectHeader *eohptr;
+
+ /* Nothing to do if it's NULL or not a varlena type */
+ if (isnull || typlen != -1)
+ return d;
+
+ /* Nothing to do if not a read-write expanded-object pointer */
+ if (!VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)))
+ return d;
+
+ /* Now safe to extract the object pointer */
+ eohptr = DatumGetEOHP(d);
+
+ /* Return the built-in read-only pointer instead of given pointer */
+ return PointerGetDatum(eohptr->eoh_ro_ptr);
+ }
+
+ /*
+ * Transfer ownership of an expanded object to a new parent memory context.
+ * The object must be referenced by a R/W pointer, and what we return is
+ * always its "standard" R/W pointer, which is certain to have the same
+ * lifespan as the object itself. (The passed-in pointer might not, and
+ * in any case wouldn't provide a unique identifier if it's not that one.)
+ */
+ Datum
+ TransferExpandedObject(Datum d, MemoryContext new_parent)
+ {
+ ExpandedObjectHeader *eohptr = DatumGetEOHP(d);
+
+ /* Assert caller gave a R/W pointer */
+ Assert(VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)));
+
+ /* Transfer ownership */
+ MemoryContextSetParent(eohptr->eoh_context, new_parent);
+
+ /* Return the object's standard read-write pointer */
+ return PointerGetDatum(eohptr->eoh_rw_ptr);
+ }
+
+ /*
+ * Delete an expanded object (must be referenced by a R/W pointer).
+ */
+ void
+ DeleteExpandedObject(Datum d)
+ {
+ ExpandedObjectHeader *eohptr = DatumGetEOHP(d);
+
+ /* Assert caller gave a R/W pointer */
+ Assert(VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(d)));
+
+ /* Kill it */
+ MemoryContextDelete(eohptr->eoh_context);
+ }
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 202bc78..4b24066 100644
*** a/src/backend/utils/mmgr/mcxt.c
--- b/src/backend/utils/mmgr/mcxt.c
*************** MemoryContextSetParent(MemoryContext con
*** 266,271 ****
--- 266,275 ----
AssertArg(MemoryContextIsValid(context));
AssertArg(context != new_parent);
+ /* Fast path if it's got correct parent already */
+ if (new_parent == context->parent)
+ return;
+
/* Delink from existing parent, if any */
if (context->parent)
{
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index 40fde83..a98a7af 100644
*** a/src/include/executor/executor.h
--- b/src/include/executor/executor.h
*************** extern void FreeExprContext(ExprContext
*** 312,318 ****
extern void ReScanExprContext(ExprContext *econtext);
#define ResetExprContext(econtext) \
! MemoryContextReset((econtext)->ecxt_per_tuple_memory)
extern ExprContext *MakePerTupleExprContext(EState *estate);
--- 312,318 ----
extern void ReScanExprContext(ExprContext *econtext);
#define ResetExprContext(econtext) \
! MemoryContextResetAndDeleteChildren((econtext)->ecxt_per_tuple_memory)
extern ExprContext *MakePerTupleExprContext(EState *estate);
diff --git a/src/include/executor/spi.h b/src/include/executor/spi.h
index 9e912ba..fbcae0c 100644
*** a/src/include/executor/spi.h
--- b/src/include/executor/spi.h
*************** extern char *SPI_getnspname(Relation rel
*** 124,129 ****
--- 124,130 ----
extern void *SPI_palloc(Size size);
extern void *SPI_repalloc(void *pointer, Size size);
extern void SPI_pfree(void *pointer);
+ extern Datum SPI_datumTransfer(Datum value, bool typByVal, int typLen);
extern void SPI_freetuple(HeapTuple pointer);
extern void SPI_freetuptable(SPITupleTable *tuptable);
diff --git a/src/include/executor/tuptable.h b/src/include/executor/tuptable.h
index 48f84bf..00686b0 100644
*** a/src/include/executor/tuptable.h
--- b/src/include/executor/tuptable.h
*************** extern Datum ExecFetchSlotTupleDatum(Tup
*** 163,168 ****
--- 163,169 ----
extern HeapTuple ExecMaterializeSlot(TupleTableSlot *slot);
extern TupleTableSlot *ExecCopySlot(TupleTableSlot *dstslot,
TupleTableSlot *srcslot);
+ extern TupleTableSlot *ExecMakeSlotContentsReadOnly(TupleTableSlot *slot);
/* in access/common/heaptuple.c */
extern Datum slot_getattr(TupleTableSlot *slot, int attnum, bool *isnull);
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index 1d06f42..932a96b 100644
*** a/src/include/nodes/primnodes.h
--- b/src/include/nodes/primnodes.h
*************** typedef struct WindowFunc
*** 310,315 ****
--- 310,319 ----
* Note: the result datatype is the element type when fetching a single
* element; but it is the array type when doing subarray fetch or either
* type of store.
+ *
+ * Note: for the cases where an array is returned, if refexpr yields a R/W
+ * expanded array, then the implementation is allowed to modify that object
+ * in-place and return the same object.)
* ----------------
*/
typedef struct ArrayRef
diff --git a/src/include/postgres.h b/src/include/postgres.h
index 082c75b..5dd897a 100644
*** a/src/include/postgres.h
--- b/src/include/postgres.h
*************** typedef struct varatt_indirect
*** 88,93 ****
--- 88,110 ----
} varatt_indirect;
/*
+ * struct varatt_expanded is a "TOAST pointer" representing an out-of-line
+ * Datum that is stored in memory, in some type-specific, not necessarily
+ * physically contiguous format that is convenient for computation not
+ * storage. APIs for this, in particular the definition of struct
+ * ExpandedObjectHeader, are in src/include/utils/expandeddatum.h.
+ *
+ * Note that just as for struct varatt_external, this struct is stored
+ * unaligned within any containing tuple.
+ */
+ typedef struct ExpandedObjectHeader ExpandedObjectHeader;
+
+ typedef struct varatt_expanded
+ {
+ ExpandedObjectHeader *eohptr;
+ } varatt_expanded;
+
+ /*
* Type tag for the various sorts of "TOAST pointer" datums. The peculiar
* value for VARTAG_ONDISK comes from a requirement for on-disk compatibility
* with a previous notion that the tag field was the pointer datum's length.
*************** typedef struct varatt_indirect
*** 95,105 ****
--- 112,129 ----
typedef enum vartag_external
{
VARTAG_INDIRECT = 1,
+ VARTAG_EXPANDED_RO = 2,
+ VARTAG_EXPANDED_RW = 3,
VARTAG_ONDISK = 18
} vartag_external;
+ /* this test relies on the specific tag values above */
+ #define VARTAG_IS_EXPANDED(tag) \
+ (((tag) & ~1) == VARTAG_EXPANDED_RO)
+
#define VARTAG_SIZE(tag) \
((tag) == VARTAG_INDIRECT ? sizeof(varatt_indirect) : \
+ VARTAG_IS_EXPANDED(tag) ? sizeof(varatt_expanded) : \
(tag) == VARTAG_ONDISK ? sizeof(varatt_external) : \
TrapMacro(true, "unrecognized TOAST vartag"))
*************** typedef struct
*** 294,299 ****
--- 318,329 ----
(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK)
#define VARATT_IS_EXTERNAL_INDIRECT(PTR) \
(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_INDIRECT)
+ #define VARATT_IS_EXTERNAL_EXPANDED_RO(PTR) \
+ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RO)
+ #define VARATT_IS_EXTERNAL_EXPANDED_RW(PTR) \
+ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RW)
+ #define VARATT_IS_EXTERNAL_EXPANDED(PTR) \
+ (VARATT_IS_EXTERNAL(PTR) && VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR)))
#define VARATT_IS_SHORT(PTR) VARATT_IS_1B(PTR)
#define VARATT_IS_EXTENDED(PTR) (!VARATT_IS_4B_U(PTR))
diff --git a/src/include/utils/array.h b/src/include/utils/array.h
index 694bce7..7360f7d 100644
*** a/src/include/utils/array.h
--- b/src/include/utils/array.h
*************** extern Datum array_remove(PG_FUNCTION_AR
*** 248,253 ****
--- 248,261 ----
extern Datum array_replace(PG_FUNCTION_ARGS);
extern Datum width_bucket_array(PG_FUNCTION_ARGS);
+ extern void CopyArrayEls(ArrayType *array,
+ Datum *values,
+ bool *nulls,
+ int nitems,
+ int typlen,
+ bool typbyval,
+ char typalign,
+ bool freedata);
extern Datum array_ref(ArrayType *array, int nSubscripts, int *indx,
int arraytyplen, int elmlen, bool elmbyval, char elmalign,
bool *isNull);
*************** extern Datum array_agg_array_transfn(PG_
*** 349,354 ****
--- 357,380 ----
extern Datum array_agg_array_finalfn(PG_FUNCTION_ARGS);
/*
+ * prototypes for functions defined in array_expanded.c
+ */
+ extern Datum expand_array(Datum arraydatum, MemoryContext parentcontext,
+ int elmlen, bool elmbyval, char elmalign);
+ extern Datum array_ref_expanded(Datum arraydatum,
+ int nSubscripts, int *indx,
+ int arraytyplen,
+ int elmlen, bool elmbyval, char elmalign,
+ bool *isNull);
+ extern Datum array_set_expanded(Datum arraydatum,
+ int nSubscripts, int *indx,
+ Datum dataValue, bool isNull,
+ int arraytyplen,
+ int elmlen, bool elmbyval, char elmalign);
+ extern Datum array_push_expanded(PG_FUNCTION_ARGS);
+ extern Datum array_dims_expanded(PG_FUNCTION_ARGS);
+
+ /*
* prototypes for functions defined in array_typanalyze.c
*/
extern Datum array_typanalyze(PG_FUNCTION_ARGS);
diff --git a/src/include/utils/datum.h b/src/include/utils/datum.h
index 663414b..c572f79 100644
*** a/src/include/utils/datum.h
--- b/src/include/utils/datum.h
***************
*** 24,41 ****
extern Size datumGetSize(Datum value, bool typByVal, int typLen);
/*
! * datumCopy - make a copy of a datum.
*
* If the datatype is pass-by-reference, memory is obtained with palloc().
*/
extern Datum datumCopy(Datum value, bool typByVal, int typLen);
/*
! * datumFree - free a datum previously allocated by datumCopy, if any.
*
! * Does nothing if datatype is pass-by-value.
*/
! extern void datumFree(Datum value, bool typByVal, int typLen);
/*
* datumIsEqual
--- 24,41 ----
extern Size datumGetSize(Datum value, bool typByVal, int typLen);
/*
! * datumCopy - make a copy of a non-NULL datum.
*
* If the datatype is pass-by-reference, memory is obtained with palloc().
*/
extern Datum datumCopy(Datum value, bool typByVal, int typLen);
/*
! * datumTransfer - transfer a non-NULL datum into the current memory context.
*
! * Differs from datumCopy() in its handling of read-write expanded objects.
*/
! extern Datum datumTransfer(Datum value, bool typByVal, int typLen);
/*
* datumIsEqual
diff --git a/src/include/utils/expandeddatum.h b/src/include/utils/expandeddatum.h
index ...584d0c6 .
*** a/src/include/utils/expandeddatum.h
--- b/src/include/utils/expandeddatum.h
***************
*** 0 ****
--- 1,146 ----
+ /*-------------------------------------------------------------------------
+ *
+ * expandeddatum.h
+ * Declarations for access to "expanded" value representations.
+ *
+ * Complex data types, particularly container types such as arrays and
+ * records, usually have on-disk representations that are compact but not
+ * especially convenient to modify. What's more, when we do modify them,
+ * having to recopy all the rest of the value can be extremely inefficient.
+ * Therefore, we provide a notion of an "expanded" representation that is used
+ * only in memory and is optimized more for computation than storage.
+ * The format appearing on disk is called the data type's "flattened"
+ * representation, since it is required to be a contiguous blob of bytes --
+ * but the type can have an expanded representation that is not. Data types
+ * must provide means to translate an expanded representation back to
+ * flattened form.
+ *
+ * An expanded object is meant to survive across multiple operations, but
+ * not to be enormously long-lived; for example it might be a local variable
+ * in a PL/pgSQL procedure. So its extra bulk compared to the on-disk format
+ * is a worthwhile trade-off.
+ *
+ * References to expanded objects are a type of TOAST pointer.
+ * Because of longstanding conventions in Postgres, this means that the
+ * flattened form of such an object must always be a varlena object.
+ * Fortunately that's no restriction in practice.
+ *
+ * There are actually two kinds of TOAST pointers for expanded objects:
+ * read-only and read-write pointers. Possession of one of the latter
+ * authorizes a function to modify the value in-place rather than copying it
+ * as would normally be required. Functions should always return a read-write
+ * pointer to any new expanded object they create. Functions that modify an
+ * argument value in-place must take care that they do not corrupt the old
+ * value if they fail partway through.
+ *
+ *
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/utils/expandeddatum.h
+ *
+ *-------------------------------------------------------------------------
+ */
+ #ifndef EXPANDEDDATUM_H
+ #define EXPANDEDDATUM_H
+
+ /* Size of an EXTERNAL datum that contains a pointer to an expanded object */
+ #define EXPANDED_POINTER_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_expanded))
+
+ /*
+ * "Methods" that must be provided for any expanded object.
+ *
+ * get_flat_size: compute space needed for flattened representation (which
+ * must be a valid in-line, non-compressed, 4-byte-header varlena object).
+ *
+ * flatten_into: construct flattened representation in the caller-allocated
+ * space at *result, of size allocated_size (which will always be the result
+ * of a preceding get_flat_size call; it's passed for cross-checking).
+ *
+ * Note: construction of a heap tuple from an expanded datum calls
+ * get_flat_size twice, so it's worthwhile to make sure that that doesn't
+ * incur too much overhead.
+ */
+ typedef Size (*EOM_get_flat_size_method) (ExpandedObjectHeader *eohptr);
+ typedef void (*EOM_flatten_into_method) (ExpandedObjectHeader *eohptr,
+ void *result, Size allocated_size);
+
+ /* Struct of function pointers for an expanded object's methods */
+ typedef struct ExpandedObjectMethods
+ {
+ EOM_get_flat_size_method get_flat_size;
+ EOM_flatten_into_method flatten_into;
+ } ExpandedObjectMethods;
+
+ /*
+ * Every expanded object must contain this header; typically the header
+ * is embedded in some larger struct that adds type-specific fields.
+ *
+ * It is presumed that the header object and all subsidiary data are stored
+ * in eoh_context, so that the object can be freed by deleting that context,
+ * or its storage lifespan can be altered by reparenting the context.
+ * (In principle the object could own additional resources, such as malloc'd
+ * storage, and use a memory context reset callback to free them upon reset or
+ * deletion of eoh_context.)
+ *
+ * We set up two TOAST pointers within the standard header, one read-write
+ * and one read-only. This allows functions to return either kind of pointer
+ * without making an additional allocation, and in particular without worrying
+ * whether a separately palloc'd object would have sufficient lifespan.
+ * But note that these pointers are just a convenience; a pointer object
+ * appearing somewhere else would still be legal.
+ *
+ * The typedef declaration for this appears in postgres.h.
+ */
+ struct ExpandedObjectHeader
+ {
+ /* Phony varlena header */
+ int32 vl_len_; /* always EOH_HEADER_MAGIC, see below */
+
+ /* Pointer to methods required for object type */
+ const ExpandedObjectMethods *eoh_methods;
+
+ /* Memory context containing this header and subsidiary data */
+ MemoryContext eoh_context;
+
+ /* Standard R/W TOAST pointer for this object is kept here */
+ char eoh_rw_ptr[EXPANDED_POINTER_SIZE];
+
+ /* Standard R/O TOAST pointer for this object is kept here */
+ char eoh_ro_ptr[EXPANDED_POINTER_SIZE];
+ };
+
+ /*
+ * Particularly for read-only functions, it is handy to be able to work with
+ * either regular "flat" varlena inputs or expanded inputs of the same data
+ * type. To allow determining which case an argument-fetching macro has
+ * returned, the first int32 of an ExpandedObjectHeader always contains -1
+ * (EOH_HEADER_MAGIC to the code). This works since no 4-byte-header varlena
+ * could have that as its first 4 bytes. Caution: we could not reliably tell
+ * the difference between an ExpandedObjectHeader and a short-header object
+ * with this trick. However, it works fine for cases where the argument
+ * fetching code will return either a fully-uncompressed flat object or a
+ * expanded object.
+ */
+ #define EOH_HEADER_MAGIC (-1)
+ #define VARATT_IS_EXPANDED_HEADER(PTR) \
+ (((ExpandedObjectHeader *) (PTR))->vl_len_ == EOH_HEADER_MAGIC)
+
+ /*
+ * Generic support functions for expanded objects.
+ * (Some of these might be worth inlining later.)
+ */
+
+ extern ExpandedObjectHeader *DatumGetEOHP(Datum d);
+ extern void EOH_init_header(ExpandedObjectHeader *eohptr,
+ const ExpandedObjectMethods *methods,
+ MemoryContext obj_context);
+ extern Size EOH_get_flat_size(ExpandedObjectHeader *eohptr);
+ extern void EOH_flatten_into(ExpandedObjectHeader *eohptr,
+ void *result, Size allocated_size);
+ extern bool DatumIsReadWriteExpandedObject(Datum d, bool isnull, int16 typlen);
+ extern Datum MakeExpandedObjectReadOnly(Datum d, bool isnull, int16 typlen);
+ extern Datum TransferExpandedObject(Datum d, MemoryContext new_parent);
+ extern void DeleteExpandedObject(Datum d);
+
+ #endif /* EXPANDEDDATUM_H */
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index f364ce4..d021145 100644
*** a/src/pl/plpgsql/src/pl_comp.c
--- b/src/pl/plpgsql/src/pl_comp.c
*************** build_datatype(HeapTuple typeTup, int32
*** 2202,2207 ****
--- 2202,2223 ----
typ->typbyval = typeStruct->typbyval;
typ->typrelid = typeStruct->typrelid;
typ->typioparam = getTypeIOParam(typeTup);
+ /* Detect if type is true array, or domain thereof */
+ /* NB: this is only used to decide whether to apply expand_array */
+ if (typeStruct->typtype == TYPTYPE_BASE)
+ {
+ /* this test should match what get_element_type() checks */
+ typ->typisarray = (typeStruct->typlen == -1 &&
+ OidIsValid(typeStruct->typelem));
+ }
+ else if (typeStruct->typtype == TYPTYPE_DOMAIN)
+ {
+ /* we can short-circuit looking up base types if it's not varlena */
+ typ->typisarray = (typeStruct->typlen == -1 &&
+ OidIsValid(get_base_element_type(typeStruct->typbasetype)));
+ }
+ else
+ typ->typisarray = false;
typ->collation = typeStruct->typcollation;
if (OidIsValid(collation) && OidIsValid(typ->collation))
typ->collation = collation;
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index ae5421f..ae68afd 100644
*** a/src/pl/plpgsql/src/pl_exec.c
--- b/src/pl/plpgsql/src/pl_exec.c
***************
*** 32,37 ****
--- 32,38 ----
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/datum.h"
+ #include "utils/expandeddatum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"
*************** static void exec_assign_value(PLpgSQL_ex
*** 171,176 ****
--- 172,178 ----
Datum value, Oid valtype, bool *isNull);
static void exec_eval_datum(PLpgSQL_execstate *estate,
PLpgSQL_datum *datum,
+ bool getrwpointer,
Oid *typeid,
int32 *typetypmod,
Datum *value,
*************** plpgsql_exec_function(PLpgSQL_function *
*** 295,300 ****
--- 297,310 ----
var->value = fcinfo->arg[i];
var->isnull = fcinfo->argnull[i];
var->freeval = false;
+ /* Hack to force array parameters into expanded form */
+ if (!var->isnull && var->datatype->typisarray)
+ {
+ var->value = expand_array(var->value,
+ CurrentMemoryContext,
+ 0, 0, 0);
+ var->freeval = true;
+ }
}
break;
*************** plpgsql_exec_function(PLpgSQL_function *
*** 461,478 ****
/*
* If the function's return type isn't by value, copy the value
! * into upper executor memory context.
*/
if (!fcinfo->isnull && !func->fn_retbyval)
! {
! Size len;
! void *tmp;
!
! len = datumGetSize(estate.retval, false, func->fn_rettyplen);
! tmp = SPI_palloc(len);
! memcpy(tmp, DatumGetPointer(estate.retval), len);
! estate.retval = PointerGetDatum(tmp);
! }
}
}
--- 471,484 ----
/*
* If the function's return type isn't by value, copy the value
! * into upper executor memory context. However, if we have a R/W
! * expanded datum, we can just transfer its ownership out to the
! * upper executor context.
*/
if (!fcinfo->isnull && !func->fn_retbyval)
! estate.retval = SPI_datumTransfer(estate.retval,
! false,
! func->fn_rettyplen);
}
}
*************** exec_assign_value(PLpgSQL_execstate *est
*** 4059,4084 ****
/*
* If type is by-reference, copy the new value (which is
* probably in the eval_econtext) into the procedure's memory
! * context.
*/
if (!var->datatype->typbyval && !*isNull)
! newvalue = datumCopy(newvalue,
! false,
! var->datatype->typlen);
/*
! * Now free the old value. (We can't do this any earlier
! * because of the possibility that we are assigning the var's
! * old value to it, eg "foo := foo". We could optimize out
! * the assignment altogether in such cases, but it's too
! * infrequent to be worth testing for.)
*/
! free_var(var);
var->value = newvalue;
var->isnull = *isNull;
! if (!var->datatype->typbyval && !*isNull)
! var->freeval = true;
break;
}
--- 4065,4115 ----
/*
* If type is by-reference, copy the new value (which is
* probably in the eval_econtext) into the procedure's memory
! * context. But if it's a read/write reference to an expanded
! * object, no physical copy needs to happen; at most we need
! * to reparent the object's memory context.
*/
if (!var->datatype->typbyval && !*isNull)
! {
! newvalue = datumTransfer(newvalue,
! false,
! var->datatype->typlen);
!
! /*
! * If it's an array, force the value to be stored in
! * expanded form. This wins if the function later does,
! * eg, a lot of array subscripting operations on the
! * variable, and otherwise might lose badly. We might
! * need to use a different heuristic, but it's too soon to
! * tell. Also, what of cases where it'd be useful to
! * force non-array values into expanded form?
! */
! if (var->datatype->typisarray &&
! !VARATT_IS_EXTERNAL_EXPANDED_RW(DatumGetPointer(newvalue)))
! {
! Datum avalue;
!
! avalue = expand_array(newvalue, CurrentMemoryContext,
! 0, 0, 0);
! pfree(DatumGetPointer(newvalue));
! newvalue = avalue;
! }
! }
/*
! * Now free the old value, unless it's the same as the new
! * value (ie, we're doing "foo := foo"). Note that for
! * expanded objects, this test is necessary and cannot
! * reliably be made any earlier; we have to be looking at the
! * object's standard R/W pointer to be sure pointer equality
! * is meaningful.
*/
! if (var->value != newvalue || var->isnull || *isNull)
! free_var(var);
var->value = newvalue;
var->isnull = *isNull;
! var->freeval = (!var->datatype->typbyval && !*isNull);
break;
}
*************** exec_assign_value(PLpgSQL_execstate *est
*** 4276,4282 ****
} while (target->dtype == PLPGSQL_DTYPE_ARRAYELEM);
/* Fetch current value of array datum */
! exec_eval_datum(estate, target,
&parenttypoid, &parenttypmod,
&oldarraydatum, &oldarrayisnull);
--- 4307,4313 ----
} while (target->dtype == PLPGSQL_DTYPE_ARRAYELEM);
/* Fetch current value of array datum */
! exec_eval_datum(estate, target, true,
&parenttypoid, &parenttypmod,
&oldarraydatum, &oldarrayisnull);
*************** exec_assign_value(PLpgSQL_execstate *est
*** 4424,4439 ****
*
* The type oid, typmod, value in Datum format, and null flag are returned.
*
* At present this doesn't handle PLpgSQL_expr or PLpgSQL_arrayelem datums.
*
! * NOTE: caller must not modify the returned value, since it points right
! * at the stored value in the case of pass-by-reference datatypes. In some
! * cases we have to palloc a return value, and in such cases we put it into
! * the estate's short-term memory context.
*/
static void
exec_eval_datum(PLpgSQL_execstate *estate,
PLpgSQL_datum *datum,
Oid *typeid,
int32 *typetypmod,
Datum *value,
--- 4455,4474 ----
*
* The type oid, typmod, value in Datum format, and null flag are returned.
*
+ * If getrwpointer is TRUE, we'll return a R/W pointer to any variable that
+ * is an expanded object; otherwise we return a R/O pointer.
+ *
* At present this doesn't handle PLpgSQL_expr or PLpgSQL_arrayelem datums.
*
! * NOTE: in most cases caller must not modify the returned value, since
! * it points right at the stored value in the case of pass-by-reference
! * datatypes. In some cases we have to palloc a return value, and in such
! * cases we put it into the estate's short-term memory context.
*/
static void
exec_eval_datum(PLpgSQL_execstate *estate,
PLpgSQL_datum *datum,
+ bool getrwpointer,
Oid *typeid,
int32 *typetypmod,
Datum *value,
*************** exec_eval_datum(PLpgSQL_execstate *estat
*** 4449,4455 ****
*typeid = var->datatype->typoid;
*typetypmod = var->datatype->atttypmod;
! *value = var->value;
*isnull = var->isnull;
break;
}
--- 4484,4495 ----
*typeid = var->datatype->typoid;
*typetypmod = var->datatype->atttypmod;
! if (getrwpointer)
! *value = var->value;
! else
! *value = MakeExpandedObjectReadOnly(var->value,
! var->isnull,
! var->datatype->typlen);
*isnull = var->isnull;
break;
}
*************** setup_param_list(PLpgSQL_execstate *esta
*** 5285,5291 ****
PLpgSQL_var *var = (PLpgSQL_var *) datum;
ParamExternData *prm = ¶mLI->params[dno];
! prm->value = var->value;
prm->isnull = var->isnull;
prm->pflags = PARAM_FLAG_CONST;
prm->ptype = var->datatype->typoid;
--- 5325,5333 ----
PLpgSQL_var *var = (PLpgSQL_var *) datum;
ParamExternData *prm = ¶mLI->params[dno];
! prm->value = MakeExpandedObjectReadOnly(var->value,
! var->isnull,
! var->datatype->typlen);
prm->isnull = var->isnull;
prm->pflags = PARAM_FLAG_CONST;
prm->ptype = var->datatype->typoid;
*************** plpgsql_param_fetch(ParamListInfo params
*** 5351,5357 ****
/* OK, evaluate the value and store into the appropriate paramlist slot */
datum = estate->datums[dno];
prm = ¶ms->params[dno];
! exec_eval_datum(estate, datum,
&prm->ptype, &prmtypmod,
&prm->value, &prm->isnull);
}
--- 5393,5399 ----
/* OK, evaluate the value and store into the appropriate paramlist slot */
datum = estate->datums[dno];
prm = ¶ms->params[dno];
! exec_eval_datum(estate, datum, false,
&prm->ptype, &prmtypmod,
&prm->value, &prm->isnull);
}
*************** make_tuple_from_row(PLpgSQL_execstate *e
*** 5543,5549 ****
if (row->varnos[i] < 0) /* should not happen */
elog(ERROR, "dropped rowtype entry for non-dropped column");
! exec_eval_datum(estate, estate->datums[row->varnos[i]],
&fieldtypeid, &fieldtypmod,
&dvalues[i], &nulls[i]);
if (fieldtypeid != tupdesc->attrs[i]->atttypid)
--- 5585,5591 ----
if (row->varnos[i] < 0) /* should not happen */
elog(ERROR, "dropped rowtype entry for non-dropped column");
! exec_eval_datum(estate, estate->datums[row->varnos[i]], false,
&fieldtypeid, &fieldtypmod,
&dvalues[i], &nulls[i]);
if (fieldtypeid != tupdesc->attrs[i]->atttypid)
*************** free_var(PLpgSQL_var *var)
*** 6336,6342 ****
{
if (var->freeval)
{
! pfree(DatumGetPointer(var->value));
var->freeval = false;
}
}
--- 6378,6389 ----
{
if (var->freeval)
{
! if (DatumIsReadWriteExpandedObject(var->value,
! var->isnull,
! var->datatype->typlen))
! DeleteExpandedObject(var->value);
! else
! pfree(DatumGetPointer(var->value));
var->freeval = false;
}
}
*************** format_expr_params(PLpgSQL_execstate *es
*** 6543,6550 ****
curvar = (PLpgSQL_var *) estate->datums[dno];
! exec_eval_datum(estate, (PLpgSQL_datum *) curvar, ¶mtypeid,
! ¶mtypmod, ¶mdatum, ¶misnull);
appendStringInfo(¶mstr, "%s%s = ",
paramno > 0 ? ", " : "",
--- 6590,6598 ----
curvar = (PLpgSQL_var *) estate->datums[dno];
! exec_eval_datum(estate, (PLpgSQL_datum *) curvar, false,
! ¶mtypeid, ¶mtypmod,
! ¶mdatum, ¶misnull);
appendStringInfo(¶mstr, "%s%s = ",
paramno > 0 ? ", " : "",
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 00f2f77..c95087c 100644
*** a/src/pl/plpgsql/src/plpgsql.h
--- b/src/pl/plpgsql/src/plpgsql.h
*************** typedef struct
*** 180,185 ****
--- 180,186 ----
bool typbyval;
Oid typrelid;
Oid typioparam;
+ bool typisarray; /* is "true" array, or domain over one */
Oid collation; /* from pg_type, but can be overridden */
FmgrInfo typinput; /* lookup info for typinput function */
int32 atttypmod; /* typmod (taken from someplace else) */
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