diff options
| -rw-r--r-- | src/backend/utils/adt/orderedsetaggs.c | 21 | ||||
| -rw-r--r-- | src/backend/utils/sort/tuplesort.c | 22 |
2 files changed, 21 insertions, 22 deletions
diff --git a/src/backend/utils/adt/orderedsetaggs.c b/src/backend/utils/adt/orderedsetaggs.c index 8502fcfc82e..c1d50eb345e 100644 --- a/src/backend/utils/adt/orderedsetaggs.c +++ b/src/backend/utils/adt/orderedsetaggs.c @@ -458,10 +458,9 @@ percentile_disc_final(PG_FUNCTION_ARGS) elog(ERROR, "missing row in percentile_disc"); /* - * Note: we *cannot* clean up the tuplesort object here, because the value - * to be returned is allocated inside its sortcontext. We could use - * datumCopy to copy it out of there, but it doesn't seem worth the - * trouble, since the cleanup callback will clear the tuplesort later. + * Note: we could clean up the tuplesort object here, but it doesn't seem + * worth the trouble, since the cleanup callback will clear the tuplesort + * later. */ /* We shouldn't have stored any nulls, but do the right thing anyway */ @@ -576,10 +575,9 @@ percentile_cont_final_common(FunctionCallInfo fcinfo, } /* - * Note: we *cannot* clean up the tuplesort object here, because the value - * to be returned may be allocated inside its sortcontext. We could use - * datumCopy to copy it out of there, but it doesn't seem worth the - * trouble, since the cleanup callback will clear the tuplesort later. + * Note: we could clean up the tuplesort object here, but it doesn't seem + * worth the trouble, since the cleanup callback will clear the tuplesort + * later. */ PG_RETURN_DATUM(val); @@ -1098,10 +1096,9 @@ mode_final(PG_FUNCTION_ARGS) pfree(DatumGetPointer(last_val)); /* - * Note: we *cannot* clean up the tuplesort object here, because the value - * to be returned is allocated inside its sortcontext. We could use - * datumCopy to copy it out of there, but it doesn't seem worth the - * trouble, since the cleanup callback will clear the tuplesort later. + * Note: we could clean up the tuplesort object here, but it doesn't seem + * worth the trouble, since the cleanup callback will clear the tuplesort + * later. */ if (mode_freq) diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c index 59cd28e595f..f895a3ae743 100644 --- a/src/backend/utils/sort/tuplesort.c +++ b/src/backend/utils/sort/tuplesort.c @@ -2102,12 +2102,13 @@ tuplesort_gettuple_common(Tuplesortstate *state, bool forward, * NULL value in leading attribute will set abbreviated value to zeroed * representation, which caller may rely on in abbreviated inequality check. * - * If copy is true, the slot receives a copied tuple that will stay valid - * regardless of future manipulations of the tuplesort's state. Memory is - * owned by the caller. If copy is false, the slot will just receive a - * pointer to a tuple held within the tuplesort, which is more efficient, but - * only safe for callers that are prepared to have any subsequent manipulation - * of the tuplesort's state invalidate slot contents. + * If copy is true, the slot receives a tuple that's been copied into the + * caller's memory context, so that it will stay valid regardless of future + * manipulations of the tuplesort's state (up to and including deleting the + * tuplesort). If copy is false, the slot will just receive a pointer to a + * tuple held within the tuplesort, which is more efficient, but only safe for + * callers that are prepared to have any subsequent manipulation of the + * tuplesort's state invalidate slot contents. */ bool tuplesort_gettupleslot(Tuplesortstate *state, bool forward, bool copy, @@ -2185,8 +2186,8 @@ tuplesort_getindextuple(Tuplesortstate *state, bool forward) * Returns FALSE if no more datums. * * If the Datum is pass-by-ref type, the returned value is freshly palloc'd - * and is now owned by the caller (this differs from similar routines for - * other types of tuplesorts). + * in caller's context, and is now owned by the caller (this differs from + * similar routines for other types of tuplesorts). * * Caller may optionally be passed back abbreviated value (on TRUE return * value) when abbreviation was used, which can be used to cheaply avoid @@ -2208,6 +2209,9 @@ tuplesort_getdatum(Tuplesortstate *state, bool forward, return false; } + /* Ensure we copy into caller's memory context */ + MemoryContextSwitchTo(oldcontext); + /* Record abbreviated key for caller */ if (state->sortKeys->abbrev_converter && abbrev) *abbrev = stup.datum1; @@ -2224,8 +2228,6 @@ tuplesort_getdatum(Tuplesortstate *state, bool forward, *isNull = false; } - MemoryContextSwitchTo(oldcontext); - return true; } |