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/*
* contrib/hstore/hstore.h
*/
#ifndef __HSTORE_H__
#define __HSTORE_H__
#include "fmgr.h"
#include "utils/array.h"
/*
* HEntry: there is one of these for each key _and_ value in an hstore
*
* the position offset points to the _end_ so that we can get the length
* by subtraction from the previous entry. the ISFIRST flag lets us tell
* whether there is a previous entry.
*/
typedef struct
{
uint32 entry;
} HEntry;
#define HENTRY_ISFIRST 0x80000000
#define HENTRY_ISNULL 0x40000000
#define HENTRY_POSMASK 0x3FFFFFFF
/* note possible multiple evaluations, also access to prior array element */
#define HSE_ISFIRST(he_) (((he_).entry & HENTRY_ISFIRST) != 0)
#define HSE_ISNULL(he_) (((he_).entry & HENTRY_ISNULL) != 0)
#define HSE_ENDPOS(he_) ((he_).entry & HENTRY_POSMASK)
#define HSE_OFF(he_) (HSE_ISFIRST(he_) ? 0 : HSE_ENDPOS((&(he_))[-1]))
#define HSE_LEN(he_) (HSE_ISFIRST(he_) \
? HSE_ENDPOS(he_) \
: HSE_ENDPOS(he_) - HSE_ENDPOS((&(he_))[-1]))
/*
* determined by the size of "endpos" (ie HENTRY_POSMASK), though this is a
* bit academic since currently varlenas (and hence both the input and the
* whole hstore) have the same limit
*/
#define HSTORE_MAX_KEY_LEN 0x3FFFFFFF
#define HSTORE_MAX_VALUE_LEN 0x3FFFFFFF
typedef struct
{
int32 vl_len_; /* varlena header (do not touch directly!) */
uint32 size_; /* flags and number of items in hstore */
/* array of HEntry follows */
} HStore;
/*
* It's not possible to get more than 2^28 items into an hstore, so we reserve
* the top few bits of the size field. See hstore_compat.c for one reason
* why. Some bits are left for future use here. MaxAllocSize makes the
* practical count limit slightly more than 2^28 / 3, or INT_MAX / 24, the
* limit for an hstore full of 4-byte keys and null values. Therefore, we
* don't explicitly check the format-imposed limit.
*/
#define HS_FLAG_NEWVERSION 0x80000000
#define HS_COUNT(hsp_) ((hsp_)->size_ & 0x0FFFFFFF)
#define HS_SETCOUNT(hsp_,c_) ((hsp_)->size_ = (c_) | HS_FLAG_NEWVERSION)
/*
* "x" comes from an existing HS_COUNT() (as discussed, <= INT_MAX/24) or a
* Pairs array length (due to MaxAllocSize, <= INT_MAX/40). "lenstr" is no
* more than INT_MAX, that extreme case arising in hstore_from_arrays().
* Therefore, this calculation is limited to about INT_MAX / 5 + INT_MAX.
*/
#define HSHRDSIZE (sizeof(HStore))
#define CALCDATASIZE(x, lenstr) ( (x) * 2 * sizeof(HEntry) + HSHRDSIZE + (lenstr) )
/* note multiple evaluations of x */
#define ARRPTR(x) ( (HEntry*) ( (HStore*)(x) + 1 ) )
#define STRPTR(x) ( (char*)(ARRPTR(x) + HS_COUNT((HStore*)(x)) * 2) )
/* note multiple/non evaluations */
#define HSTORE_KEY(arr_,str_,i_) ((str_) + HSE_OFF((arr_)[2*(i_)]))
#define HSTORE_VAL(arr_,str_,i_) ((str_) + HSE_OFF((arr_)[2*(i_)+1]))
#define HSTORE_KEYLEN(arr_,i_) (HSE_LEN((arr_)[2*(i_)]))
#define HSTORE_VALLEN(arr_,i_) (HSE_LEN((arr_)[2*(i_)+1]))
#define HSTORE_VALISNULL(arr_,i_) (HSE_ISNULL((arr_)[2*(i_)+1]))
/*
* currently, these following macros are the _only_ places that rely
* on internal knowledge of HEntry. Everything else should be using
* the above macros. Exception: the in-place upgrade in hstore_compat.c
* messes with entries directly.
*/
/*
* copy one key/value pair (which must be contiguous starting at
* sptr_) into an under-construction hstore; dent_ is an HEntry*,
* dbuf_ is the destination's string buffer, dptr_ is the current
* position in the destination. lots of modification and multiple
* evaluation here.
*/
#define HS_COPYITEM(dent_,dbuf_,dptr_,sptr_,klen_,vlen_,vnull_) \
do { \
memcpy((dptr_), (sptr_), (klen_)+(vlen_)); \
(dptr_) += (klen_)+(vlen_); \
(dent_)++->entry = ((dptr_) - (dbuf_) - (vlen_)) & HENTRY_POSMASK; \
(dent_)++->entry = ((((dptr_) - (dbuf_)) & HENTRY_POSMASK) \
| ((vnull_) ? HENTRY_ISNULL : 0)); \
} while(0)
/*
* add one key/item pair, from a Pairs structure, into an
* under-construction hstore
*/
#define HS_ADDITEM(dent_,dbuf_,dptr_,pair_) \
do { \
memcpy((dptr_), (pair_).key, (pair_).keylen); \
(dptr_) += (pair_).keylen; \
(dent_)++->entry = ((dptr_) - (dbuf_)) & HENTRY_POSMASK; \
if ((pair_).isnull) \
(dent_)++->entry = ((((dptr_) - (dbuf_)) & HENTRY_POSMASK) \
| HENTRY_ISNULL); \
else \
{ \
memcpy((dptr_), (pair_).val, (pair_).vallen); \
(dptr_) += (pair_).vallen; \
(dent_)++->entry = ((dptr_) - (dbuf_)) & HENTRY_POSMASK; \
} \
} while (0)
/* finalize a newly-constructed hstore */
#define HS_FINALIZE(hsp_,count_,buf_,ptr_) \
do { \
int buflen = (ptr_) - (buf_); \
if ((count_)) \
ARRPTR(hsp_)[0].entry |= HENTRY_ISFIRST; \
if ((count_) != HS_COUNT((hsp_))) \
{ \
HS_SETCOUNT((hsp_),(count_)); \
memmove(STRPTR(hsp_), (buf_), buflen); \
} \
SET_VARSIZE((hsp_), CALCDATASIZE((count_), buflen)); \
} while (0)
/* ensure the varlena size of an existing hstore is correct */
#define HS_FIXSIZE(hsp_,count_) \
do { \
int bl = (count_) ? HSE_ENDPOS(ARRPTR(hsp_)[2*(count_)-1]) : 0; \
SET_VARSIZE((hsp_), CALCDATASIZE((count_),bl)); \
} while (0)
/* DatumGetHStoreP includes support for reading old-format hstore values */
extern HStore *hstoreUpgrade(Datum orig);
#define DatumGetHStoreP(d) hstoreUpgrade(d)
#define PG_GETARG_HSTORE_P(x) DatumGetHStoreP(PG_GETARG_DATUM(x))
/*
* Pairs is a "decompressed" representation of one key/value pair.
* The two strings are not necessarily null-terminated.
*/
typedef struct
{
char *key;
char *val;
size_t keylen;
size_t vallen;
bool isnull; /* value is null? */
bool needfree; /* need to pfree the value? */
} Pairs;
extern int hstoreUniquePairs(Pairs *a, int32 l, int32 *buflen);
extern HStore *hstorePairs(Pairs *pairs, int32 pcount, int32 buflen);
extern size_t hstoreCheckKeyLen(size_t len);
extern size_t hstoreCheckValLen(size_t len);
extern int hstoreFindKey(HStore *hs, int *lowbound, char *key, int keylen);
extern Pairs *hstoreArrayToPairs(ArrayType *a, int *npairs);
#define HStoreContainsStrategyNumber 7
#define HStoreExistsStrategyNumber 9
#define HStoreExistsAnyStrategyNumber 10
#define HStoreExistsAllStrategyNumber 11
#define HStoreOldContainsStrategyNumber 13 /* backwards compatibility */
/*
* defining HSTORE_POLLUTE_NAMESPACE=0 will prevent use of old function names;
* for now, we default to on for the benefit of people restoring old dumps
*/
#ifndef HSTORE_POLLUTE_NAMESPACE
#define HSTORE_POLLUTE_NAMESPACE 1
#endif
#if HSTORE_POLLUTE_NAMESPACE
#define HSTORE_POLLUTE(newname_,oldname_) \
PG_FUNCTION_INFO_V1(oldname_); \
Datum newname_(PG_FUNCTION_ARGS); \
Datum oldname_(PG_FUNCTION_ARGS) { return newname_(fcinfo); } \
extern int no_such_variable
#else
#define HSTORE_POLLUTE(newname_,oldname_) \
extern int no_such_variable
#endif
#endif /* __HSTORE_H__ */
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