postgresql/contrib/hstore/hstore_op.c
Alvaro Herrera c219d9b0a5 Split tuple struct defs from htup.h to htup_details.h
This reduces unnecessary exposure of other headers through htup.h, which
is very widely included by many files.

I have chosen to move the function prototypes to the new file as well,
because that means htup.h no longer needs to include tupdesc.h.  In
itself this doesn't have much effect in indirect inclusion of tupdesc.h
throughout the tree, because it's also required by execnodes.h; but it's
something to explore in the future, and it seemed best to do the htup.h
change now while I'm busy with it.
2012-08-30 16:52:35 -04:00

1265 lines
27 KiB
C

/*
* contrib/hstore/hstore_op.c
*/
#include "postgres.h"
#include "access/hash.h"
#include "access/htup_details.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "utils/builtins.h"
#include "hstore.h"
/* old names for C functions */
HSTORE_POLLUTE(hstore_fetchval, fetchval);
HSTORE_POLLUTE(hstore_exists, exists);
HSTORE_POLLUTE(hstore_defined, defined);
HSTORE_POLLUTE(hstore_delete, delete);
HSTORE_POLLUTE(hstore_concat, hs_concat);
HSTORE_POLLUTE(hstore_contains, hs_contains);
HSTORE_POLLUTE(hstore_contained, hs_contained);
HSTORE_POLLUTE(hstore_akeys, akeys);
HSTORE_POLLUTE(hstore_avals, avals);
HSTORE_POLLUTE(hstore_skeys, skeys);
HSTORE_POLLUTE(hstore_svals, svals);
HSTORE_POLLUTE(hstore_each, each);
/*
* We're often finding a sequence of keys in ascending order. The
* "lowbound" parameter is used to cache lower bounds of searches
* between calls, based on this assumption. Pass NULL for it for
* one-off or unordered searches.
*/
int
hstoreFindKey(HStore *hs, int *lowbound, char *key, int keylen)
{
HEntry *entries = ARRPTR(hs);
int stopLow = lowbound ? *lowbound : 0;
int stopHigh = HS_COUNT(hs);
int stopMiddle;
char *base = STRPTR(hs);
while (stopLow < stopHigh)
{
int difference;
stopMiddle = stopLow + (stopHigh - stopLow) / 2;
if (HS_KEYLEN(entries, stopMiddle) == keylen)
difference = memcmp(HS_KEY(entries, base, stopMiddle), key, keylen);
else
difference = (HS_KEYLEN(entries, stopMiddle) > keylen) ? 1 : -1;
if (difference == 0)
{
if (lowbound)
*lowbound = stopMiddle + 1;
return stopMiddle;
}
else if (difference < 0)
stopLow = stopMiddle + 1;
else
stopHigh = stopMiddle;
}
if (lowbound)
*lowbound = stopLow;
return -1;
}
Pairs *
hstoreArrayToPairs(ArrayType *a, int *npairs)
{
Datum *key_datums;
bool *key_nulls;
int key_count;
Pairs *key_pairs;
int bufsiz;
int i,
j;
deconstruct_array(a,
TEXTOID, -1, false, 'i',
&key_datums, &key_nulls, &key_count);
if (key_count == 0)
{
*npairs = 0;
return NULL;
}
key_pairs = palloc(sizeof(Pairs) * key_count);
for (i = 0, j = 0; i < key_count; i++)
{
if (!key_nulls[i])
{
key_pairs[j].key = VARDATA(key_datums[i]);
key_pairs[j].keylen = VARSIZE(key_datums[i]) - VARHDRSZ;
key_pairs[j].val = NULL;
key_pairs[j].vallen = 0;
key_pairs[j].needfree = 0;
key_pairs[j].isnull = 1;
j++;
}
}
*npairs = hstoreUniquePairs(key_pairs, j, &bufsiz);
return key_pairs;
}
PG_FUNCTION_INFO_V1(hstore_fetchval);
Datum hstore_fetchval(PG_FUNCTION_ARGS);
Datum
hstore_fetchval(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
text *key = PG_GETARG_TEXT_PP(1);
HEntry *entries = ARRPTR(hs);
text *out;
int idx = hstoreFindKey(hs, NULL,
VARDATA_ANY(key), VARSIZE_ANY_EXHDR(key));
if (idx < 0 || HS_VALISNULL(entries, idx))
PG_RETURN_NULL();
out = cstring_to_text_with_len(HS_VAL(entries, STRPTR(hs), idx),
HS_VALLEN(entries, idx));
PG_RETURN_TEXT_P(out);
}
PG_FUNCTION_INFO_V1(hstore_exists);
Datum hstore_exists(PG_FUNCTION_ARGS);
Datum
hstore_exists(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
text *key = PG_GETARG_TEXT_PP(1);
int idx = hstoreFindKey(hs, NULL,
VARDATA_ANY(key), VARSIZE_ANY_EXHDR(key));
PG_RETURN_BOOL(idx >= 0);
}
PG_FUNCTION_INFO_V1(hstore_exists_any);
Datum hstore_exists_any(PG_FUNCTION_ARGS);
Datum
hstore_exists_any(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
ArrayType *keys = PG_GETARG_ARRAYTYPE_P(1);
int nkeys;
Pairs *key_pairs = hstoreArrayToPairs(keys, &nkeys);
int i;
int lowbound = 0;
bool res = false;
/*
* we exploit the fact that the pairs list is already sorted into strictly
* increasing order to narrow the hstoreFindKey search; each search can
* start one entry past the previous "found" entry, or at the lower bound
* of the last search.
*/
for (i = 0; i < nkeys; i++)
{
int idx = hstoreFindKey(hs, &lowbound,
key_pairs[i].key, key_pairs[i].keylen);
if (idx >= 0)
{
res = true;
break;
}
}
PG_RETURN_BOOL(res);
}
PG_FUNCTION_INFO_V1(hstore_exists_all);
Datum hstore_exists_all(PG_FUNCTION_ARGS);
Datum
hstore_exists_all(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
ArrayType *keys = PG_GETARG_ARRAYTYPE_P(1);
int nkeys;
Pairs *key_pairs = hstoreArrayToPairs(keys, &nkeys);
int i;
int lowbound = 0;
bool res = true;
/*
* we exploit the fact that the pairs list is already sorted into strictly
* increasing order to narrow the hstoreFindKey search; each search can
* start one entry past the previous "found" entry, or at the lower bound
* of the last search.
*/
for (i = 0; i < nkeys; i++)
{
int idx = hstoreFindKey(hs, &lowbound,
key_pairs[i].key, key_pairs[i].keylen);
if (idx < 0)
{
res = false;
break;
}
}
PG_RETURN_BOOL(res);
}
PG_FUNCTION_INFO_V1(hstore_defined);
Datum hstore_defined(PG_FUNCTION_ARGS);
Datum
hstore_defined(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
text *key = PG_GETARG_TEXT_PP(1);
HEntry *entries = ARRPTR(hs);
int idx = hstoreFindKey(hs, NULL,
VARDATA_ANY(key), VARSIZE_ANY_EXHDR(key));
bool res = (idx >= 0 && !HS_VALISNULL(entries, idx));
PG_RETURN_BOOL(res);
}
PG_FUNCTION_INFO_V1(hstore_delete);
Datum hstore_delete(PG_FUNCTION_ARGS);
Datum
hstore_delete(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
text *key = PG_GETARG_TEXT_PP(1);
char *keyptr = VARDATA_ANY(key);
int keylen = VARSIZE_ANY_EXHDR(key);
HStore *out = palloc(VARSIZE(hs));
char *bufs,
*bufd,
*ptrd;
HEntry *es,
*ed;
int i;
int count = HS_COUNT(hs);
int outcount = 0;
SET_VARSIZE(out, VARSIZE(hs));
HS_SETCOUNT(out, count); /* temporary! */
bufs = STRPTR(hs);
es = ARRPTR(hs);
bufd = ptrd = STRPTR(out);
ed = ARRPTR(out);
for (i = 0; i < count; ++i)
{
int len = HS_KEYLEN(es, i);
char *ptrs = HS_KEY(es, bufs, i);
if (!(len == keylen && memcmp(ptrs, keyptr, keylen) == 0))
{
int vallen = HS_VALLEN(es, i);
HS_COPYITEM(ed, bufd, ptrd, ptrs, len, vallen, HS_VALISNULL(es, i));
++outcount;
}
}
HS_FINALIZE(out, outcount, bufd, ptrd);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_delete_array);
Datum hstore_delete_array(PG_FUNCTION_ARGS);
Datum
hstore_delete_array(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
HStore *out = palloc(VARSIZE(hs));
int hs_count = HS_COUNT(hs);
char *ps,
*bufd,
*pd;
HEntry *es,
*ed;
int i,
j;
int outcount = 0;
ArrayType *key_array = PG_GETARG_ARRAYTYPE_P(1);
int nkeys;
Pairs *key_pairs = hstoreArrayToPairs(key_array, &nkeys);
SET_VARSIZE(out, VARSIZE(hs));
HS_SETCOUNT(out, hs_count); /* temporary! */
ps = STRPTR(hs);
es = ARRPTR(hs);
bufd = pd = STRPTR(out);
ed = ARRPTR(out);
if (nkeys == 0)
{
/* return a copy of the input, unchanged */
memcpy(out, hs, VARSIZE(hs));
HS_FIXSIZE(out, hs_count);
HS_SETCOUNT(out, hs_count);
PG_RETURN_POINTER(out);
}
/*
* this is in effect a merge between hs and key_pairs, both of which are
* already sorted by (keylen,key); we take keys from hs only
*/
for (i = j = 0; i < hs_count;)
{
int difference;
if (j >= nkeys)
difference = -1;
else
{
int skeylen = HS_KEYLEN(es, i);
if (skeylen == key_pairs[j].keylen)
difference = memcmp(HS_KEY(es, ps, i),
key_pairs[j].key,
key_pairs[j].keylen);
else
difference = (skeylen > key_pairs[j].keylen) ? 1 : -1;
}
if (difference > 0)
++j;
else if (difference == 0)
++i, ++j;
else
{
HS_COPYITEM(ed, bufd, pd,
HS_KEY(es, ps, i), HS_KEYLEN(es, i),
HS_VALLEN(es, i), HS_VALISNULL(es, i));
++outcount;
++i;
}
}
HS_FINALIZE(out, outcount, bufd, pd);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_delete_hstore);
Datum hstore_delete_hstore(PG_FUNCTION_ARGS);
Datum
hstore_delete_hstore(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
HStore *hs2 = PG_GETARG_HS(1);
HStore *out = palloc(VARSIZE(hs));
int hs_count = HS_COUNT(hs);
int hs2_count = HS_COUNT(hs2);
char *ps,
*ps2,
*bufd,
*pd;
HEntry *es,
*es2,
*ed;
int i,
j;
int outcount = 0;
SET_VARSIZE(out, VARSIZE(hs));
HS_SETCOUNT(out, hs_count); /* temporary! */
ps = STRPTR(hs);
es = ARRPTR(hs);
ps2 = STRPTR(hs2);
es2 = ARRPTR(hs2);
bufd = pd = STRPTR(out);
ed = ARRPTR(out);
if (hs2_count == 0)
{
/* return a copy of the input, unchanged */
memcpy(out, hs, VARSIZE(hs));
HS_FIXSIZE(out, hs_count);
HS_SETCOUNT(out, hs_count);
PG_RETURN_POINTER(out);
}
/*
* this is in effect a merge between hs and hs2, both of which are already
* sorted by (keylen,key); we take keys from hs only; for equal keys, we
* take the value from hs unless the values are equal
*/
for (i = j = 0; i < hs_count;)
{
int difference;
if (j >= hs2_count)
difference = -1;
else
{
int skeylen = HS_KEYLEN(es, i);
int s2keylen = HS_KEYLEN(es2, j);
if (skeylen == s2keylen)
difference = memcmp(HS_KEY(es, ps, i),
HS_KEY(es2, ps2, j),
skeylen);
else
difference = (skeylen > s2keylen) ? 1 : -1;
}
if (difference > 0)
++j;
else if (difference == 0)
{
int svallen = HS_VALLEN(es, i);
int snullval = HS_VALISNULL(es, i);
if (snullval != HS_VALISNULL(es2, j)
|| (!snullval
&& (svallen != HS_VALLEN(es2, j)
|| memcmp(HS_VAL(es, ps, i), HS_VAL(es2, ps2, j), svallen) != 0)))
{
HS_COPYITEM(ed, bufd, pd,
HS_KEY(es, ps, i), HS_KEYLEN(es, i),
svallen, snullval);
++outcount;
}
++i, ++j;
}
else
{
HS_COPYITEM(ed, bufd, pd,
HS_KEY(es, ps, i), HS_KEYLEN(es, i),
HS_VALLEN(es, i), HS_VALISNULL(es, i));
++outcount;
++i;
}
}
HS_FINALIZE(out, outcount, bufd, pd);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_concat);
Datum hstore_concat(PG_FUNCTION_ARGS);
Datum
hstore_concat(PG_FUNCTION_ARGS)
{
HStore *s1 = PG_GETARG_HS(0);
HStore *s2 = PG_GETARG_HS(1);
HStore *out = palloc(VARSIZE(s1) + VARSIZE(s2));
char *ps1,
*ps2,
*bufd,
*pd;
HEntry *es1,
*es2,
*ed;
int s1idx;
int s2idx;
int s1count = HS_COUNT(s1);
int s2count = HS_COUNT(s2);
int outcount = 0;
SET_VARSIZE(out, VARSIZE(s1) + VARSIZE(s2) - HSHRDSIZE);
HS_SETCOUNT(out, s1count + s2count);
if (s1count == 0)
{
/* return a copy of the input, unchanged */
memcpy(out, s2, VARSIZE(s2));
HS_FIXSIZE(out, s2count);
HS_SETCOUNT(out, s2count);
PG_RETURN_POINTER(out);
}
if (s2count == 0)
{
/* return a copy of the input, unchanged */
memcpy(out, s1, VARSIZE(s1));
HS_FIXSIZE(out, s1count);
HS_SETCOUNT(out, s1count);
PG_RETURN_POINTER(out);
}
ps1 = STRPTR(s1);
ps2 = STRPTR(s2);
bufd = pd = STRPTR(out);
es1 = ARRPTR(s1);
es2 = ARRPTR(s2);
ed = ARRPTR(out);
/*
* this is in effect a merge between s1 and s2, both of which are already
* sorted by (keylen,key); we take s2 for equal keys
*/
for (s1idx = s2idx = 0; s1idx < s1count || s2idx < s2count; ++outcount)
{
int difference;
if (s1idx >= s1count)
difference = 1;
else if (s2idx >= s2count)
difference = -1;
else
{
int s1keylen = HS_KEYLEN(es1, s1idx);
int s2keylen = HS_KEYLEN(es2, s2idx);
if (s1keylen == s2keylen)
difference = memcmp(HS_KEY(es1, ps1, s1idx),
HS_KEY(es2, ps2, s2idx),
s1keylen);
else
difference = (s1keylen > s2keylen) ? 1 : -1;
}
if (difference >= 0)
{
HS_COPYITEM(ed, bufd, pd,
HS_KEY(es2, ps2, s2idx), HS_KEYLEN(es2, s2idx),
HS_VALLEN(es2, s2idx), HS_VALISNULL(es2, s2idx));
++s2idx;
if (difference == 0)
++s1idx;
}
else
{
HS_COPYITEM(ed, bufd, pd,
HS_KEY(es1, ps1, s1idx), HS_KEYLEN(es1, s1idx),
HS_VALLEN(es1, s1idx), HS_VALISNULL(es1, s1idx));
++s1idx;
}
}
HS_FINALIZE(out, outcount, bufd, pd);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_slice_to_array);
Datum hstore_slice_to_array(PG_FUNCTION_ARGS);
Datum
hstore_slice_to_array(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
HEntry *entries = ARRPTR(hs);
char *ptr = STRPTR(hs);
ArrayType *key_array = PG_GETARG_ARRAYTYPE_P(1);
ArrayType *aout;
Datum *key_datums;
bool *key_nulls;
Datum *out_datums;
bool *out_nulls;
int key_count;
int i;
deconstruct_array(key_array,
TEXTOID, -1, false, 'i',
&key_datums, &key_nulls, &key_count);
if (key_count == 0)
{
aout = construct_empty_array(TEXTOID);
PG_RETURN_POINTER(aout);
}
out_datums = palloc(sizeof(Datum) * key_count);
out_nulls = palloc(sizeof(bool) * key_count);
for (i = 0; i < key_count; ++i)
{
text *key = (text *) DatumGetPointer(key_datums[i]);
int idx;
if (key_nulls[i])
idx = -1;
else
idx = hstoreFindKey(hs, NULL, VARDATA(key), VARSIZE(key) - VARHDRSZ);
if (idx < 0 || HS_VALISNULL(entries, idx))
{
out_nulls[i] = true;
out_datums[i] = (Datum) 0;
}
else
{
out_datums[i] = PointerGetDatum(
cstring_to_text_with_len(HS_VAL(entries, ptr, idx),
HS_VALLEN(entries, idx)));
out_nulls[i] = false;
}
}
aout = construct_md_array(out_datums, out_nulls,
ARR_NDIM(key_array),
ARR_DIMS(key_array),
ARR_LBOUND(key_array),
TEXTOID, -1, false, 'i');
PG_RETURN_POINTER(aout);
}
PG_FUNCTION_INFO_V1(hstore_slice_to_hstore);
Datum hstore_slice_to_hstore(PG_FUNCTION_ARGS);
Datum
hstore_slice_to_hstore(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
HEntry *entries = ARRPTR(hs);
char *ptr = STRPTR(hs);
ArrayType *key_array = PG_GETARG_ARRAYTYPE_P(1);
HStore *out;
int nkeys;
Pairs *key_pairs = hstoreArrayToPairs(key_array, &nkeys);
Pairs *out_pairs;
int bufsiz;
int lastidx = 0;
int i;
int out_count = 0;
if (nkeys == 0)
{
out = hstorePairs(NULL, 0, 0);
PG_RETURN_POINTER(out);
}
out_pairs = palloc(sizeof(Pairs) * nkeys);
bufsiz = 0;
/*
* we exploit the fact that the pairs list is already sorted into strictly
* increasing order to narrow the hstoreFindKey search; each search can
* start one entry past the previous "found" entry, or at the lower bound
* of the last search.
*/
for (i = 0; i < nkeys; ++i)
{
int idx = hstoreFindKey(hs, &lastidx,
key_pairs[i].key, key_pairs[i].keylen);
if (idx >= 0)
{
out_pairs[out_count].key = key_pairs[i].key;
bufsiz += (out_pairs[out_count].keylen = key_pairs[i].keylen);
out_pairs[out_count].val = HS_VAL(entries, ptr, idx);
bufsiz += (out_pairs[out_count].vallen = HS_VALLEN(entries, idx));
out_pairs[out_count].isnull = HS_VALISNULL(entries, idx);
out_pairs[out_count].needfree = false;
++out_count;
}
}
/*
* we don't use uniquePairs here because we know that the pairs list is
* already sorted and uniq'ed.
*/
out = hstorePairs(out_pairs, out_count, bufsiz);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_akeys);
Datum hstore_akeys(PG_FUNCTION_ARGS);
Datum
hstore_akeys(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
Datum *d;
ArrayType *a;
HEntry *entries = ARRPTR(hs);
char *base = STRPTR(hs);
int count = HS_COUNT(hs);
int i;
if (count == 0)
{
a = construct_empty_array(TEXTOID);
PG_RETURN_POINTER(a);
}
d = (Datum *) palloc(sizeof(Datum) * count);
for (i = 0; i < count; ++i)
{
text *item = cstring_to_text_with_len(HS_KEY(entries, base, i),
HS_KEYLEN(entries, i));
d[i] = PointerGetDatum(item);
}
a = construct_array(d, count,
TEXTOID, -1, false, 'i');
PG_RETURN_POINTER(a);
}
PG_FUNCTION_INFO_V1(hstore_avals);
Datum hstore_avals(PG_FUNCTION_ARGS);
Datum
hstore_avals(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
Datum *d;
bool *nulls;
ArrayType *a;
HEntry *entries = ARRPTR(hs);
char *base = STRPTR(hs);
int count = HS_COUNT(hs);
int lb = 1;
int i;
if (count == 0)
{
a = construct_empty_array(TEXTOID);
PG_RETURN_POINTER(a);
}
d = (Datum *) palloc(sizeof(Datum) * count);
nulls = (bool *) palloc(sizeof(bool) * count);
for (i = 0; i < count; ++i)
{
if (HS_VALISNULL(entries, i))
{
d[i] = (Datum) 0;
nulls[i] = true;
}
else
{
text *item = cstring_to_text_with_len(HS_VAL(entries, base, i),
HS_VALLEN(entries, i));
d[i] = PointerGetDatum(item);
nulls[i] = false;
}
}
a = construct_md_array(d, nulls, 1, &count, &lb,
TEXTOID, -1, false, 'i');
PG_RETURN_POINTER(a);
}
static ArrayType *
hstore_to_array_internal(HStore *hs, int ndims)
{
HEntry *entries = ARRPTR(hs);
char *base = STRPTR(hs);
int count = HS_COUNT(hs);
int out_size[2] = {0, 2};
int lb[2] = {1, 1};
Datum *out_datums;
bool *out_nulls;
int i;
Assert(ndims < 3);
if (count == 0 || ndims == 0)
return construct_empty_array(TEXTOID);
out_size[0] = count * 2 / ndims;
out_datums = palloc(sizeof(Datum) * count * 2);
out_nulls = palloc(sizeof(bool) * count * 2);
for (i = 0; i < count; ++i)
{
text *key = cstring_to_text_with_len(HS_KEY(entries, base, i),
HS_KEYLEN(entries, i));
out_datums[i * 2] = PointerGetDatum(key);
out_nulls[i * 2] = false;
if (HS_VALISNULL(entries, i))
{
out_datums[i * 2 + 1] = (Datum) 0;
out_nulls[i * 2 + 1] = true;
}
else
{
text *item = cstring_to_text_with_len(HS_VAL(entries, base, i),
HS_VALLEN(entries, i));
out_datums[i * 2 + 1] = PointerGetDatum(item);
out_nulls[i * 2 + 1] = false;
}
}
return construct_md_array(out_datums, out_nulls,
ndims, out_size, lb,
TEXTOID, -1, false, 'i');
}
PG_FUNCTION_INFO_V1(hstore_to_array);
Datum hstore_to_array(PG_FUNCTION_ARGS);
Datum
hstore_to_array(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
ArrayType *out = hstore_to_array_internal(hs, 1);
PG_RETURN_POINTER(out);
}
PG_FUNCTION_INFO_V1(hstore_to_matrix);
Datum hstore_to_matrix(PG_FUNCTION_ARGS);
Datum
hstore_to_matrix(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
ArrayType *out = hstore_to_array_internal(hs, 2);
PG_RETURN_POINTER(out);
}
/*
* Common initialization function for the various set-returning
* funcs. fcinfo is only passed if the function is to return a
* composite; it will be used to look up the return tupledesc.
* we stash a copy of the hstore in the multi-call context in
* case it was originally toasted. (At least I assume that's why;
* there was no explanatory comment in the original code. --AG)
*/
static void
setup_firstcall(FuncCallContext *funcctx, HStore *hs,
FunctionCallInfoData *fcinfo)
{
MemoryContext oldcontext;
HStore *st;
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
st = (HStore *) palloc(VARSIZE(hs));
memcpy(st, hs, VARSIZE(hs));
funcctx->user_fctx = (void *) st;
if (fcinfo)
{
TupleDesc tupdesc;
/* Build a tuple descriptor for our result type */
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
elog(ERROR, "return type must be a row type");
funcctx->tuple_desc = BlessTupleDesc(tupdesc);
}
MemoryContextSwitchTo(oldcontext);
}
PG_FUNCTION_INFO_V1(hstore_skeys);
Datum hstore_skeys(PG_FUNCTION_ARGS);
Datum
hstore_skeys(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
HStore *hs;
int i;
if (SRF_IS_FIRSTCALL())
{
hs = PG_GETARG_HS(0);
funcctx = SRF_FIRSTCALL_INIT();
setup_firstcall(funcctx, hs, NULL);
}
funcctx = SRF_PERCALL_SETUP();
hs = (HStore *) funcctx->user_fctx;
i = funcctx->call_cntr;
if (i < HS_COUNT(hs))
{
HEntry *entries = ARRPTR(hs);
text *item;
item = cstring_to_text_with_len(HS_KEY(entries, STRPTR(hs), i),
HS_KEYLEN(entries, i));
SRF_RETURN_NEXT(funcctx, PointerGetDatum(item));
}
SRF_RETURN_DONE(funcctx);
}
PG_FUNCTION_INFO_V1(hstore_svals);
Datum hstore_svals(PG_FUNCTION_ARGS);
Datum
hstore_svals(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
HStore *hs;
int i;
if (SRF_IS_FIRSTCALL())
{
hs = PG_GETARG_HS(0);
funcctx = SRF_FIRSTCALL_INIT();
setup_firstcall(funcctx, hs, NULL);
}
funcctx = SRF_PERCALL_SETUP();
hs = (HStore *) funcctx->user_fctx;
i = funcctx->call_cntr;
if (i < HS_COUNT(hs))
{
HEntry *entries = ARRPTR(hs);
if (HS_VALISNULL(entries, i))
{
ReturnSetInfo *rsi;
/* ugly ugly ugly. why no macro for this? */
(funcctx)->call_cntr++;
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
rsi->isDone = ExprMultipleResult;
PG_RETURN_NULL();
}
else
{
text *item;
item = cstring_to_text_with_len(HS_VAL(entries, STRPTR(hs), i),
HS_VALLEN(entries, i));
SRF_RETURN_NEXT(funcctx, PointerGetDatum(item));
}
}
SRF_RETURN_DONE(funcctx);
}
PG_FUNCTION_INFO_V1(hstore_contains);
Datum hstore_contains(PG_FUNCTION_ARGS);
Datum
hstore_contains(PG_FUNCTION_ARGS)
{
HStore *val = PG_GETARG_HS(0);
HStore *tmpl = PG_GETARG_HS(1);
bool res = true;
HEntry *te = ARRPTR(tmpl);
char *tstr = STRPTR(tmpl);
HEntry *ve = ARRPTR(val);
char *vstr = STRPTR(val);
int tcount = HS_COUNT(tmpl);
int lastidx = 0;
int i;
/*
* we exploit the fact that keys in "tmpl" are in strictly increasing
* order to narrow the hstoreFindKey search; each search can start one
* entry past the previous "found" entry, or at the lower bound of the
* search
*/
for (i = 0; res && i < tcount; ++i)
{
int idx = hstoreFindKey(val, &lastidx,
HS_KEY(te, tstr, i), HS_KEYLEN(te, i));
if (idx >= 0)
{
bool nullval = HS_VALISNULL(te, i);
int vallen = HS_VALLEN(te, i);
if (nullval != HS_VALISNULL(ve, idx)
|| (!nullval
&& (vallen != HS_VALLEN(ve, idx)
|| memcmp(HS_VAL(te, tstr, i), HS_VAL(ve, vstr, idx), vallen))))
res = false;
}
else
res = false;
}
PG_RETURN_BOOL(res);
}
PG_FUNCTION_INFO_V1(hstore_contained);
Datum hstore_contained(PG_FUNCTION_ARGS);
Datum
hstore_contained(PG_FUNCTION_ARGS)
{
PG_RETURN_DATUM(DirectFunctionCall2(hstore_contains,
PG_GETARG_DATUM(1),
PG_GETARG_DATUM(0)
));
}
PG_FUNCTION_INFO_V1(hstore_each);
Datum hstore_each(PG_FUNCTION_ARGS);
Datum
hstore_each(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
HStore *hs;
int i;
if (SRF_IS_FIRSTCALL())
{
hs = PG_GETARG_HS(0);
funcctx = SRF_FIRSTCALL_INIT();
setup_firstcall(funcctx, hs, fcinfo);
}
funcctx = SRF_PERCALL_SETUP();
hs = (HStore *) funcctx->user_fctx;
i = funcctx->call_cntr;
if (i < HS_COUNT(hs))
{
HEntry *entries = ARRPTR(hs);
char *ptr = STRPTR(hs);
Datum res,
dvalues[2];
bool nulls[2] = {false, false};
text *item;
HeapTuple tuple;
item = cstring_to_text_with_len(HS_KEY(entries, ptr, i),
HS_KEYLEN(entries, i));
dvalues[0] = PointerGetDatum(item);
if (HS_VALISNULL(entries, i))
{
dvalues[1] = (Datum) 0;
nulls[1] = true;
}
else
{
item = cstring_to_text_with_len(HS_VAL(entries, ptr, i),
HS_VALLEN(entries, i));
dvalues[1] = PointerGetDatum(item);
}
tuple = heap_form_tuple(funcctx->tuple_desc, dvalues, nulls);
res = HeapTupleGetDatum(tuple);
SRF_RETURN_NEXT(funcctx, PointerGetDatum(res));
}
SRF_RETURN_DONE(funcctx);
}
/*
* btree sort order for hstores isn't intended to be useful; we really only
* care about equality versus non-equality. we compare the entire string
* buffer first, then the entry pos array.
*/
PG_FUNCTION_INFO_V1(hstore_cmp);
Datum hstore_cmp(PG_FUNCTION_ARGS);
Datum
hstore_cmp(PG_FUNCTION_ARGS)
{
HStore *hs1 = PG_GETARG_HS(0);
HStore *hs2 = PG_GETARG_HS(1);
int hcount1 = HS_COUNT(hs1);
int hcount2 = HS_COUNT(hs2);
int res = 0;
if (hcount1 == 0 || hcount2 == 0)
{
/*
* if either operand is empty, and the other is nonempty, the nonempty
* one is larger. If both are empty they are equal.
*/
if (hcount1 > 0)
res = 1;
else if (hcount2 > 0)
res = -1;
}
else
{
/* here we know both operands are nonempty */
char *str1 = STRPTR(hs1);
char *str2 = STRPTR(hs2);
HEntry *ent1 = ARRPTR(hs1);
HEntry *ent2 = ARRPTR(hs2);
size_t len1 = HSE_ENDPOS(ent1[2 * hcount1 - 1]);
size_t len2 = HSE_ENDPOS(ent2[2 * hcount2 - 1]);
res = memcmp(str1, str2, Min(len1, len2));
if (res == 0)
{
if (len1 > len2)
res = 1;
else if (len1 < len2)
res = -1;
else if (hcount1 > hcount2)
res = 1;
else if (hcount2 > hcount1)
res = -1;
else
{
int count = hcount1 * 2;
int i;
for (i = 0; i < count; ++i)
if (HSE_ENDPOS(ent1[i]) != HSE_ENDPOS(ent2[i]) ||
HSE_ISNULL(ent1[i]) != HSE_ISNULL(ent2[i]))
break;
if (i < count)
{
if (HSE_ENDPOS(ent1[i]) < HSE_ENDPOS(ent2[i]))
res = -1;
else if (HSE_ENDPOS(ent1[i]) > HSE_ENDPOS(ent2[i]))
res = 1;
else if (HSE_ISNULL(ent1[i]))
res = 1;
else if (HSE_ISNULL(ent2[i]))
res = -1;
}
}
}
else
{
res = (res > 0) ? 1 : -1;
}
}
/*
* this is a btree support function; this is one of the few places where
* memory needs to be explicitly freed.
*/
PG_FREE_IF_COPY(hs1, 0);
PG_FREE_IF_COPY(hs2, 1);
PG_RETURN_INT32(res);
}
PG_FUNCTION_INFO_V1(hstore_eq);
Datum hstore_eq(PG_FUNCTION_ARGS);
Datum
hstore_eq(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res == 0);
}
PG_FUNCTION_INFO_V1(hstore_ne);
Datum hstore_ne(PG_FUNCTION_ARGS);
Datum
hstore_ne(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res != 0);
}
PG_FUNCTION_INFO_V1(hstore_gt);
Datum hstore_gt(PG_FUNCTION_ARGS);
Datum
hstore_gt(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res > 0);
}
PG_FUNCTION_INFO_V1(hstore_ge);
Datum hstore_ge(PG_FUNCTION_ARGS);
Datum
hstore_ge(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res >= 0);
}
PG_FUNCTION_INFO_V1(hstore_lt);
Datum hstore_lt(PG_FUNCTION_ARGS);
Datum
hstore_lt(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res < 0);
}
PG_FUNCTION_INFO_V1(hstore_le);
Datum hstore_le(PG_FUNCTION_ARGS);
Datum
hstore_le(PG_FUNCTION_ARGS)
{
int res = DatumGetInt32(DirectFunctionCall2(hstore_cmp,
PG_GETARG_DATUM(0),
PG_GETARG_DATUM(1)));
PG_RETURN_BOOL(res <= 0);
}
PG_FUNCTION_INFO_V1(hstore_hash);
Datum hstore_hash(PG_FUNCTION_ARGS);
Datum
hstore_hash(PG_FUNCTION_ARGS)
{
HStore *hs = PG_GETARG_HS(0);
Datum hval = hash_any((unsigned char *) VARDATA(hs),
VARSIZE(hs) - VARHDRSZ);
/*
* this is the only place in the code that cares whether the overall
* varlena size exactly matches the true data size; this assertion should
* be maintained by all the other code, but we make it explicit here.
*/
Assert(VARSIZE(hs) ==
(HS_COUNT(hs) != 0 ?
CALCDATASIZE(HS_COUNT(hs),
HSE_ENDPOS(ARRPTR(hs)[2 * HS_COUNT(hs) - 1])) :
HSHRDSIZE));
PG_FREE_IF_COPY(hs, 0);
PG_RETURN_DATUM(hval);
}