postgresql/contrib/hstore_plperl/hstore_plperl.c
Peter Eisentraut cac7658205 Add transforms feature
This provides a mechanism for specifying conversions between SQL data
types and procedural languages.  As examples, there are transforms
for hstore and ltree for PL/Perl and PL/Python.

reviews by Pavel Stěhule and Andres Freund
2015-04-26 10:33:14 -04:00

91 lines
1.7 KiB
C

#include "postgres.h"
#undef _
#include "fmgr.h"
#include "plperl.h"
#include "plperl_helpers.h"
#include "hstore.h"
PG_MODULE_MAGIC;
PG_FUNCTION_INFO_V1(hstore_to_plperl);
Datum hstore_to_plperl(PG_FUNCTION_ARGS);
Datum
hstore_to_plperl(PG_FUNCTION_ARGS)
{
HStore *in = PG_GETARG_HS(0);
int i;
int count = HS_COUNT(in);
char *base = STRPTR(in);
HEntry *entries = ARRPTR(in);
HV *hv;
hv = newHV();
for (i = 0; i < count; i++)
{
const char *key;
SV *value;
key = pnstrdup(HS_KEY(entries, base, i), HS_KEYLEN(entries, i));
value = HS_VALISNULL(entries, i) ? newSV(0) : cstr2sv(pnstrdup(HS_VAL(entries, base,i), HS_VALLEN(entries, i)));
(void) hv_store(hv, key, strlen(key), value, 0);
}
return PointerGetDatum(newRV((SV *) hv));
}
PG_FUNCTION_INFO_V1(plperl_to_hstore);
Datum plperl_to_hstore(PG_FUNCTION_ARGS);
Datum
plperl_to_hstore(PG_FUNCTION_ARGS)
{
HV *hv;
HE *he;
int32 buflen;
int32 i;
int32 pcount;
HStore *out;
Pairs *pairs;
hv = (HV *) SvRV((SV *) PG_GETARG_POINTER(0));
pcount = hv_iterinit(hv);
pairs = palloc(pcount * sizeof(Pairs));
i = 0;
while ((he = hv_iternext(hv)))
{
char *key = sv2cstr(HeSVKEY_force(he));
SV *value = HeVAL(he);
pairs[i].key = pstrdup(key);
pairs[i].keylen = hstoreCheckKeyLen(strlen(pairs[i].key));
pairs[i].needfree = true;
if (!SvOK(value))
{
pairs[i].val = NULL;
pairs[i].vallen = 0;
pairs[i].isnull = true;
}
else
{
pairs[i].val = pstrdup(sv2cstr(value));
pairs[i].vallen = hstoreCheckValLen(strlen(pairs[i].val));
pairs[i].isnull = false;
}
i++;
}
pcount = hstoreUniquePairs(pairs, pcount, &buflen);
out = hstorePairs(pairs, pcount, buflen);
PG_RETURN_POINTER(out);
}