/*------------------------------------------------------------------------- * * array.h * Declarations for Postgres arrays. * * A standard varlena array has the following internal structure: * - standard varlena header word * - number of dimensions of the array * - offset to stored data, or 0 if no nulls bitmap * - element type OID * - length of each array axis (C array of int) * - lower boundary of each dimension (C array of int) * - bitmap showing locations of nulls (OPTIONAL) * - whatever is the stored data * * The and arrays each have ndim elements. * * The may be omitted if the array contains no NULL elements. * If it is absent, the field is zero and the offset to the * stored data must be computed on-the-fly. If the bitmap is present, * 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. * * In addition, arrays are a major user of the "expanded object" TOAST * infrastructure. This allows a varlena array to be converted to a * separate representation that may include "deconstructed" Datum/isnull * arrays holding the elements. * * * Portions Copyright (c) 1996-2015, 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" #include "utils/expandeddatum.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; /* * 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; /* * 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; /* * working state for accumArrayResult() and friends * note that the input must be scalars (legal array elements) */ 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; bool private_cxt; /* use private memory context */ } ArrayBuildState; /* * working state for accumArrayResultArr() and friends * note that the input must be arrays, and the same array type is returned */ typedef struct ArrayBuildStateArr { MemoryContext mcontext; /* where all the temp stuff is kept */ char *data; /* accumulated data */ bits8 *nullbitmap; /* bitmap of is-null flags, or NULL if none */ int abytes; /* allocated length of "data" */ int nbytes; /* number of bytes used so far */ int aitems; /* allocated length of bitmap (in elements) */ int nitems; /* total number of elements in result */ int ndims; /* current dimensions of result */ int dims[MAXDIM]; int lbs[MAXDIM]; Oid array_type; /* data type of the arrays */ Oid element_type; /* data type of the array elements */ bool private_cxt; /* use private memory context */ } ArrayBuildStateArr; /* * working state for accumArrayResultAny() and friends * these functions handle both cases */ typedef struct ArrayBuildStateAny { /* Exactly one of these is not NULL: */ ArrayBuildState *scalarstate; ArrayBuildStateArr *arraystate; } ArrayBuildStateAny; /* * 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 regular varlena 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) /* fmgr macros for expanded array objects */ #define PG_GETARG_EXPANDED_ARRAY(n) DatumGetExpandedArray(PG_GETARG_DATUM(n)) #define PG_GETARG_EXPANDED_ARRAYX(n, metacache) \ DatumGetExpandedArrayX(PG_GETARG_DATUM(n), metacache) #define PG_RETURN_EXPANDED_ARRAY(x) PG_RETURN_DATUM(EOHPGetRWDatum(&(x)->hdr)) /* fmgr macros for AnyArrayType (ie, get either varlena or expanded form) */ #define PG_GETARG_ANY_ARRAY(n) DatumGetAnyArray(PG_GETARG_DATUM(n)) /* * Access macros for varlena 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)) /* * 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)) /* * 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_cardinality(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_remove(PG_FUNCTION_ARGS); 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_get_element(Datum arraydatum, int nSubscripts, int *indx, int arraytyplen, int elmlen, bool elmbyval, char elmalign, bool *isNull); extern Datum array_set_element(Datum arraydatum, int nSubscripts, int *indx, Datum dataValue, bool isNull, int arraytyplen, int elmlen, bool elmbyval, char elmalign); extern Datum array_get_slice(Datum arraydatum, int nSubscripts, int *upperIndx, int *lowerIndx, int arraytyplen, int elmlen, bool elmbyval, char elmalign); extern Datum array_set_slice(Datum arraydatum, int nSubscripts, int *upperIndx, int *lowerIndx, Datum srcArrayDatum, bool isNull, int arraytyplen, int elmlen, bool elmbyval, char elmalign); 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 Datum array_map(FunctionCallInfo fcinfo, 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 ExpandedArrayHeader *construct_empty_expanded_array(Oid element_type, MemoryContext parentcontext, ArrayMetaState *metacache); 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 *initArrayResult(Oid element_type, MemoryContext rcontext, bool subcontext); 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 ArrayBuildStateArr *initArrayResultArr(Oid array_type, Oid element_type, MemoryContext rcontext, bool subcontext); extern ArrayBuildStateArr *accumArrayResultArr(ArrayBuildStateArr *astate, Datum dvalue, bool disnull, Oid array_type, MemoryContext rcontext); extern Datum makeArrayResultArr(ArrayBuildStateArr *astate, MemoryContext rcontext, bool release); extern ArrayBuildStateAny *initArrayResultAny(Oid input_type, MemoryContext rcontext, bool subcontext); extern ArrayBuildStateAny *accumArrayResultAny(ArrayBuildStateAny *astate, Datum dvalue, bool disnull, Oid input_type, MemoryContext rcontext); extern Datum makeArrayResultAny(ArrayBuildStateAny *astate, MemoryContext rcontext, bool release); extern ArrayIterator array_create_iterator(ArrayType *arr, int slice_ndim, ArrayMetaState *mstate); 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_expanded.c */ extern Datum expand_array(Datum arraydatum, MemoryContext parentcontext, ArrayMetaState *metacache); extern ExpandedArrayHeader *DatumGetExpandedArray(Datum d); extern ExpandedArrayHeader *DatumGetExpandedArrayX(Datum d, ArrayMetaState *metacache); extern AnyArrayType *DatumGetAnyArray(Datum d); extern void deconstruct_expanded_array(ExpandedArrayHeader *eah); /* * prototypes for functions defined in array_userfuncs.c */ extern Datum array_append(PG_FUNCTION_ARGS); extern Datum array_prepend(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); extern Datum array_agg_array_transfn(PG_FUNCTION_ARGS); extern Datum array_agg_array_finalfn(PG_FUNCTION_ARGS); extern Datum array_position(PG_FUNCTION_ARGS); extern Datum array_position_start(PG_FUNCTION_ARGS); extern Datum array_positions(PG_FUNCTION_ARGS); /* * prototypes for functions defined in array_typanalyze.c */ extern Datum array_typanalyze(PG_FUNCTION_ARGS); #endif /* ARRAY_H */