Datum
hstore_version_diag(PG_FUNCTION_ARGS)
{
HStore *hs = (HStore *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
int valid_new = hstoreValidNewFormat(hs);
int valid_old = hstoreValidOldFormat(hs);
PG_RETURN_INT32(valid_old * 10 + valid_new);
}
/*
* hstoreUpgrade: PG_DETOAST_DATUM plus support for conversion of old hstores
*/
HStore *
hstoreUpgrade(Datum orig)
{
HStore *hs = (HStore *) PG_DETOAST_DATUM(orig);
int valid_new;
int valid_old;
bool writable;
/* Return immediately if no conversion needed */
if ((hs->size_ & HS_FLAG_NEWVERSION) ||
hs->size_ == 0 ||
(VARSIZE(hs) < 32768 && HSE_ISFIRST((ARRPTR(hs)[0]))))
return hs;
valid_new = hstoreValidNewFormat(hs);
valid_old = hstoreValidOldFormat(hs);
/* Do we have a writable copy? */
writable = ((void *) hs != (void *) DatumGetPointer(orig));
if (!valid_old || hs->size_ == 0)
{
if (valid_new)
{
/*
* force the "new version" flag and the correct varlena length,
* but only if we have a writable copy already (which we almost
* always will, since short new-format values won't come through
* here)
*/
if (writable)
{
HS_SETCOUNT(hs, HS_COUNT(hs));
HS_FIXSIZE(hs, HS_COUNT(hs));
}
return hs;
}
else
{
elog(ERROR, "invalid hstore value found");
}
}
/*
* this is the tricky edge case. It is only possible in some quite extreme
* cases (the hstore must have had a lot of wasted padding space at the
* end). But the only way a "new" hstore value could get here is if we're
* upgrading in place from a pre-release version of hstore-new (NOT
* contrib/hstore), so we work off the following assumptions: 1. If you're
* moving from old contrib/hstore to hstore-new, you're required to fix up
* any potential conflicts first, e.g. by running ALTER TABLE ... USING
* col::text::hstore; on all hstore columns before upgrading. 2. If you're
* moving from old contrib/hstore to new contrib/hstore, then "new" values
* are impossible here 3. If you're moving from pre-release hstore-new to
* hstore-new, then "old" values are impossible here 4. If you're moving
* from pre-release hstore-new to new contrib/hstore, you're not doing so
* as an in-place upgrade, so there is no issue So the upshot of all this
* is that we can treat all the edge cases as "new" if we're being built
* as hstore-new, and "old" if we're being built as contrib/hstore.
*
* XXX the WARNING can probably be downgraded to DEBUG1 once this has been
* beta-tested. But for now, it would be very useful to know if anyone can
* actually reach this case in a non-contrived setting.
*/
if (valid_new)
{
#if HSTORE_IS_HSTORE_NEW
elog(WARNING, "ambiguous hstore value resolved as hstore-new");
/*
* force the "new version" flag and the correct varlena length, but
* only if we have a writable copy already (which we almost always
* will, since short new-format values won't come through here)
*/
if (writable)
{
HS_SETCOUNT(hs, HS_COUNT(hs));
HS_FIXSIZE(hs, HS_COUNT(hs));
}
return hs;
#else
elog(WARNING, "ambiguous hstore value resolved as hstore-old");
#endif
}
/*
* must have an old-style value. Overwrite it in place as a new-style one,
* making sure we have a writable copy first.
*/
if (!writable)
hs = (HStore *) PG_DETOAST_DATUM_COPY(orig);
{
int count = hs->size_;
HEntry *new_entries = ARRPTR(hs);
HOldEntry *old_entries = (HOldEntry *) ARRPTR(hs);
int i;
for (i = 0; i < count; ++i)
{
uint32 pos = old_entries[i].pos;
uint32 keylen = old_entries[i].keylen;
uint32 vallen = old_entries[i].vallen;
bool isnull = old_entries[i].valisnull;
if (isnull)
vallen = 0;
new_entries[2 * i].entry = (pos + keylen) & HENTRY_POSMASK;
new_entries[2 * i + 1].entry = (((pos + keylen + vallen) & HENTRY_POSMASK)
| ((isnull) ? HENTRY_ISNULL : 0));
}
if (count)
new_entries[0].entry |= HENTRY_ISFIRST;
HS_SETCOUNT(hs, count);
HS_FIXSIZE(hs, count);
}
return hs;
}
