/* check whether the content in the given bytea is safe for mfvtransval */
void check_mfvtransval(bytea *storage) {
size_t left_len = VARSIZE(storage);
size_t cur_size = 0;
size_t cur_capacity = 0;
Oid outFuncOid;
bool typIsVarLen;
mfvtransval *mfv = NULL;
if (left_len < VARHDRSZ + sizeof(mfvtransval)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
mfv = (mfvtransval*)VARDATA(storage);
left_len -= VARHDRSZ + sizeof(mfvtransval);
if (mfv->next_mfv > mfv->max_mfvs) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (mfv->next_offset + VARHDRSZ > VARSIZE(storage)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (InvalidOid == mfv->typOid) {
elog(ERROR, "invalid transition state for mfvsketch");
}
getTypeOutputInfo(mfv->typOid, &outFuncOid, &typIsVarLen);
if (mfv->outFuncOid != outFuncOid
|| mfv->typLen != get_typlen(mfv->typOid)
|| mfv->typByVal != get_typbyval(mfv->typOid)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (left_len < sizeof(offsetcnt)*mfv->max_mfvs) {
elog(ERROR, "invalid transition state for mfvsketch");
}
/* offset is relative to mfvtransval */
left_len = VARSIZE(storage) - VARHDRSZ;
/*
* the following checking may be inefficiency, but by doing this centrally,
* we can avoid spreading the checking code everywhere.
*/
for (unsigned i = 0; i < mfv->next_mfv; i ++) {
cur_capacity = left_len - mfv->mfvs[i].offset;
if (mfv->mfvs[i].offset > left_len) {
elog(ERROR, "invalid transition state for mfvsketch");
}
cur_size = ExtractDatumLen(PointerGetDatum(MFV_DATA(mfv) + mfv->mfvs[i].offset),
mfv->typLen, mfv->typByVal, cur_capacity);
if (cur_size > cur_capacity) {
elog(ERROR, "invalid transition state for mfvsketch");
}
}
}
/*
* free_attstatsslot
* Free data allocated by get_attstatsslot
*
* atttype need be valid only if values != NULL.
*/
void
free_attstatsslot(Oid atttype,
Datum *values, int nvalues,
float4 *numbers, int nnumbers)
{
if (values)
{
if (!get_typbyval(atttype))
{
int i;
for (i = 0; i < nvalues; i++)
pfree(DatumGetPointer(values[i]));
}
pfree(values);
}
if (numbers)
pfree(numbers);
}
/* check whether the content in the given bytea is safe for mfvtransval */
void check_mfvtransval(bytea *storage) {
size_t left_len = VARSIZE(storage);
Oid outFuncOid;
bool typIsVarLen;
mfvtransval *mfv = NULL;
if (left_len < VARHDRSZ + sizeof(mfvtransval)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
mfv = (mfvtransval*)VARDATA(storage);
left_len -= VARHDRSZ + sizeof(mfvtransval);
if (mfv->next_mfv > mfv->max_mfvs) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (mfv->next_offset + VARHDRSZ > VARSIZE(storage)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (InvalidOid == mfv->typOid) {
elog(ERROR, "invalid transition state for mfvsketch");
}
getTypeOutputInfo(mfv->typOid, &outFuncOid, &typIsVarLen);
if (mfv->outFuncOid != outFuncOid
|| mfv->typLen != get_typlen(mfv->typOid)
|| mfv->typByVal != get_typbyval(mfv->typOid)) {
elog(ERROR, "invalid transition state for mfvsketch");
}
if (left_len < sizeof(offsetcnt)*mfv->max_mfvs) {
elog(ERROR, "invalid transition state for mfvsketch");
}
}
/*!
* Initialize an mfv sketch
* \param max_mfvs the number of "bins" in the histogram
* \param typOid the type ID for the column
*/
bytea *mfv_init_transval(int max_mfvs, Oid typOid)
{
int initial_size;
bool typIsVarLen;
bytea * transblob;
mfvtransval *transval;
/*
* initialize mfvtransval, using palloc0 to zero it out.
* if typlen is positive (fixed), size chosen accurately.
* Else we'll do a conservative estimate of 16 bytes, and repalloc as needed.
*/
if ((initial_size = get_typlen(typOid)) > 0)
initial_size *= max_mfvs*get_typlen(typOid);
else /* guess */
initial_size = max_mfvs*16;
transblob = (bytea *)palloc0(MFV_TRANSVAL_SZ(max_mfvs) + initial_size);
SET_VARSIZE(transblob, MFV_TRANSVAL_SZ(max_mfvs) + initial_size);
transval = (mfvtransval *)VARDATA(transblob);
transval->max_mfvs = max_mfvs;
transval->next_mfv = 0;
transval->next_offset = MFV_TRANSVAL_SZ(max_mfvs)-VARHDRSZ;
transval->typOid = typOid;
getTypeOutputInfo(transval->typOid,
&(transval->outFuncOid),
&(typIsVarLen));
transval->typLen = get_typlen(transval->typOid);
transval->typByVal = get_typbyval(transval->typOid);
if (!transval->outFuncOid) {
/* no outFunc for this type! */
elog(ERROR, "no outFunc for type %d", transval->typOid);
}
return(transblob);
}
