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/*-------------------------------------------------------------------------
*
* array.h
* Declarations for Postgres arrays.
*
* A standard varlena array has the following internal structure:
* <vl_len_> - standard varlena header word
* <ndim> - number of dimensions of the array
* <dataoffset> - offset to stored data, or 0 if no nulls bitmap
* <elemtype> - element type OID
* <dimensions> - length of each array axis (C array of int)
* <lower bnds> - lower boundary of each dimension (C array of int)
* <null bitmap> - bitmap showing locations of nulls (OPTIONAL)
* <actual data> - whatever is the stored data
*
* The <dimensions> and <lower bnds> arrays each have ndim elements.
*
* The <null bitmap> may be omitted if the array contains no NULL elements.
* If it is absent, the <dataoffset> field is zero and the offset to the
* stored data must be computed on-the-fly. If the bitmap is present,
* <dataoffset> is nonzero and is equal to the offset from the array start
* to the first data element (including any alignment padding). The bitmap
* follows the same conventions as tuple null bitmaps, ie, a 1 indicates
* a non-null entry and the LSB of each bitmap byte is used first.
*
* The actual data starts on a MAXALIGN boundary. Individual items in the
* array are aligned as specified by the array element type. They are
* stored in row-major order (last subscript varies most rapidly).
*
* NOTE: it is important that array elements of toastable datatypes NOT be
* toasted, since the tupletoaster won't know they are there. (We could
* support compressed toasted items; only out-of-line items are dangerous.
* However, it seems preferable to store such items uncompressed and allow
* the toaster to compress the whole array as one input.)
*
*
* The OIDVECTOR and INT2VECTOR datatypes are storage-compatible with
* generic arrays, but they support only one-dimensional arrays with no
* nulls (and no null bitmap).
*
* There are also some "fixed-length array" datatypes, such as NAME and
* POINT. These are simply a sequence of a fixed number of items each
* of a fixed-length datatype, with no overhead; the item size must be
* a multiple of its alignment requirement, because we do no padding.
* We support subscripting on these types, but array_in() and array_out()
* only work with varlena arrays.
*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/utils/array.h
*
*-------------------------------------------------------------------------
*/
#ifndef ARRAY_H
#define ARRAY_H
#include "fmgr.h"
/*
* Arrays are varlena objects, so must meet the varlena convention that
* the first int32 of the object contains the total object size in bytes.
* Be sure to use VARSIZE() and SET_VARSIZE() to access it, though!
*
* CAUTION: if you change the header for ordinary arrays you will also
* need to change the headers for oidvector and int2vector!
*/
typedef struct
{
int32 vl_len_; /* varlena header (do not touch directly!) */
int ndim; /* # of dimensions */
int32 dataoffset; /* offset to data, or 0 if no bitmap */
Oid elemtype; /* element type OID */
} ArrayType;
/*
* working state for accumArrayResult() and friends
*/
typedef struct ArrayBuildState
{
MemoryContext mcontext; /* where all the temp stuff is kept */
Datum *dvalues; /* array of accumulated Datums */
bool *dnulls; /* array of is-null flags for Datums */
int alen; /* allocated length of above arrays */
int nelems; /* number of valid entries in above arrays */
Oid element_type; /* data type of the Datums */
int16 typlen; /* needed info about datatype */
bool typbyval;
char typalign;
} ArrayBuildState;
/*
* structure to cache type metadata needed for array manipulation
*/
typedef struct ArrayMetaState
{
Oid element_type;
int16 typlen;
bool typbyval;
char typalign;
char typdelim;
Oid typioparam;
Oid typiofunc;
FmgrInfo proc;
} ArrayMetaState;
/*
* private state needed by array_map (here because caller must provide it)
*/
typedef struct ArrayMapState
{
ArrayMetaState inp_extra;
ArrayMetaState ret_extra;
} ArrayMapState;
/* ArrayIteratorData is private in arrayfuncs.c */
typedef struct ArrayIteratorData *ArrayIterator;
/*
* fmgr macros for array objects
*/
#define DatumGetArrayTypeP(X) ((ArrayType *) PG_DETOAST_DATUM(X))
#define DatumGetArrayTypePCopy(X) ((ArrayType *) PG_DETOAST_DATUM_COPY(X))
#define PG_GETARG_ARRAYTYPE_P(n) DatumGetArrayTypeP(PG_GETARG_DATUM(n))
#define PG_GETARG_ARRAYTYPE_P_COPY(n) DatumGetArrayTypePCopy(PG_GETARG_DATUM(n))
#define PG_RETURN_ARRAYTYPE_P(x) PG_RETURN_POINTER(x)
/*
* Access macros for array header fields.
*
* ARR_DIMS returns a pointer to an array of array dimensions (number of
* elements along the various array axes).
*
* ARR_LBOUND returns a pointer to an array of array lower bounds.
*
* That is: if the third axis of an array has elements 5 through 8, then
* ARR_DIMS(a)[2] == 4 and ARR_LBOUND(a)[2] == 5.
*
* Unlike C, the default lower bound is 1.
*/
#define ARR_SIZE(a) VARSIZE(a)
#define ARR_NDIM(a) ((a)->ndim)
#define ARR_HASNULL(a) ((a)->dataoffset != 0)
#define ARR_ELEMTYPE(a) ((a)->elemtype)
#define ARR_DIMS(a) \
((int *) (((char *) (a)) + sizeof(ArrayType)))
#define ARR_LBOUND(a) \
((int *) (((char *) (a)) + sizeof(ArrayType) + \
sizeof(int) * ARR_NDIM(a)))
#define ARR_NULLBITMAP(a) \
(ARR_HASNULL(a) ? \
(bits8 *) (((char *) (a)) + sizeof(ArrayType) + \
2 * sizeof(int) * ARR_NDIM(a)) \
: (bits8 *) NULL)
/*
* The total array header size (in bytes) for an array with the specified
* number of dimensions and total number of items.
*/
#define ARR_OVERHEAD_NONULLS(ndims) \
MAXALIGN(sizeof(ArrayType) + 2 * sizeof(int) * (ndims))
#define ARR_OVERHEAD_WITHNULLS(ndims, nitems) \
MAXALIGN(sizeof(ArrayType) + 2 * sizeof(int) * (ndims) + \
((nitems) + 7) / 8)
#define ARR_DATA_OFFSET(a) \
(ARR_HASNULL(a) ? (a)->dataoffset : ARR_OVERHEAD_NONULLS(ARR_NDIM(a)))
/*
* Returns a pointer to the actual array data.
*/
#define ARR_DATA_PTR(a) \
(((char *) (a)) + ARR_DATA_OFFSET(a))
/*
* GUC parameter
*/
extern bool Array_nulls;
/*
* prototypes for functions defined in arrayfuncs.c
*/
extern Datum array_in(PG_FUNCTION_ARGS);
extern Datum array_out(PG_FUNCTION_ARGS);
extern Datum array_recv(PG_FUNCTION_ARGS);
extern Datum array_send(PG_FUNCTION_ARGS);
extern Datum array_eq(PG_FUNCTION_ARGS);
extern Datum array_ne(PG_FUNCTION_ARGS);
extern Datum array_lt(PG_FUNCTION_ARGS);
extern Datum array_gt(PG_FUNCTION_ARGS);
extern Datum array_le(PG_FUNCTION_ARGS);
extern Datum array_ge(PG_FUNCTION_ARGS);
extern Datum btarraycmp(PG_FUNCTION_ARGS);
extern Datum hash_array(PG_FUNCTION_ARGS);
extern Datum arrayoverlap(PG_FUNCTION_ARGS);
extern Datum arraycontains(PG_FUNCTION_ARGS);
extern Datum arraycontained(PG_FUNCTION_ARGS);
extern Datum array_ndims(PG_FUNCTION_ARGS);
extern Datum array_dims(PG_FUNCTION_ARGS);
extern Datum array_lower(PG_FUNCTION_ARGS);
extern Datum array_upper(PG_FUNCTION_ARGS);
extern Datum array_length(PG_FUNCTION_ARGS);
extern Datum array_larger(PG_FUNCTION_ARGS);
extern Datum array_smaller(PG_FUNCTION_ARGS);
extern Datum generate_subscripts(PG_FUNCTION_ARGS);
extern Datum generate_subscripts_nodir(PG_FUNCTION_ARGS);
extern Datum array_fill(PG_FUNCTION_ARGS);
extern Datum array_fill_with_lower_bounds(PG_FUNCTION_ARGS);
extern Datum array_unnest(PG_FUNCTION_ARGS);
extern Datum array_ref(ArrayType *array, int nSubscripts, int *indx,
int arraytyplen, int elmlen, bool elmbyval, char elmalign,
bool *isNull);
extern ArrayType *array_set(ArrayType *array, int nSubscripts, int *indx,
Datum dataValue, bool isNull,
int arraytyplen, int elmlen, bool elmbyval, char elmalign);
extern ArrayType *array_get_slice(ArrayType *array, int nSubscripts,
int *upperIndx, int *lowerIndx,
int arraytyplen, int elmlen, bool elmbyval, char elmalign);
extern ArrayType *array_set_slice(ArrayType *array, int nSubscripts,
int *upperIndx, int *lowerIndx,
ArrayType *srcArray, bool isNull,
int arraytyplen, int elmlen, bool elmbyval, char elmalign);
extern Datum array_map(FunctionCallInfo fcinfo, Oid inpType, Oid retType,
ArrayMapState *amstate);
extern void array_bitmap_copy(bits8 *destbitmap, int destoffset,
const bits8 *srcbitmap, int srcoffset,
int nitems);
extern ArrayType *construct_array(Datum *elems, int nelems,
Oid elmtype,
int elmlen, bool elmbyval, char elmalign);
extern ArrayType *construct_md_array(Datum *elems,
bool *nulls,
int ndims,
int *dims,
int *lbs,
Oid elmtype, int elmlen, bool elmbyval, char elmalign);
extern ArrayType *construct_empty_array(Oid elmtype);
extern void deconstruct_array(ArrayType *array,
Oid elmtype,
int elmlen, bool elmbyval, char elmalign,
Datum **elemsp, bool **nullsp, int *nelemsp);
extern bool array_contains_nulls(ArrayType *array);
extern ArrayBuildState *accumArrayResult(ArrayBuildState *astate,
Datum dvalue, bool disnull,
Oid element_type,
MemoryContext rcontext);
extern Datum makeArrayResult(ArrayBuildState *astate,
MemoryContext rcontext);
extern Datum makeMdArrayResult(ArrayBuildState *astate, int ndims,
int *dims, int *lbs, MemoryContext rcontext, bool release);
extern ArrayIterator array_create_iterator(ArrayType *arr, int slice_ndim);
extern bool array_iterate(ArrayIterator iterator, Datum *value, bool *isnull);
extern void array_free_iterator(ArrayIterator iterator);
/*
* prototypes for functions defined in arrayutils.c
*/
extern int ArrayGetOffset(int n, const int *dim, const int *lb, const int *indx);
extern int ArrayGetOffset0(int n, const int *tup, const int *scale);
extern int ArrayGetNItems(int ndim, const int *dims);
extern void mda_get_range(int n, int *span, const int *st, const int *endp);
extern void mda_get_prod(int n, const int *range, int *prod);
extern void mda_get_offset_values(int n, int *dist, const int *prod, const int *span);
extern int mda_next_tuple(int n, int *curr, const int *span);
extern int32 *ArrayGetIntegerTypmods(ArrayType *arr, int *n);
/*
* prototypes for functions defined in array_userfuncs.c
*/
extern Datum array_push(PG_FUNCTION_ARGS);
extern Datum array_cat(PG_FUNCTION_ARGS);
extern ArrayType *create_singleton_array(FunctionCallInfo fcinfo,
Oid element_type,
Datum element,
bool isNull,
int ndims);
extern Datum array_agg_transfn(PG_FUNCTION_ARGS);
extern Datum array_agg_finalfn(PG_FUNCTION_ARGS);
/*
* prototypes for functions defined in array_typanalyze.c
*/
extern Datum array_typanalyze(PG_FUNCTION_ARGS);
#endif /* ARRAY_H */
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