*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/fmgr/fmgr.c,v 1.62 2002/09/04 20:31:30 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/fmgr/fmgr.c,v 1.63 2002/10/04 17:19:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*-------------------------------------------------------------------------
* Support routines for callers of fmgr-compatible functions
+ *
+ * NOTE: the simplest way to reliably initialize a FunctionCallInfoData
+ * is to MemSet it to zeroes and then fill in the fields that should be
+ * nonzero. However, in a few of the most heavily used paths, we instead
+ * just zero the fields that must be zero. This saves a fair number of
+ * cycles so it's worth the extra maintenance effort. Also see inlined
+ * version of FunctionCall2 in utils/sort/tuplesort.c if you need to change
+ * these routines!
*-------------------------------------------------------------------------
*/
FunctionCallInfoData fcinfo;
Datum result;
- MemSet(&fcinfo, 0, sizeof(fcinfo));
+ /* MemSet(&fcinfo, 0, sizeof(fcinfo)); */
+ fcinfo.flinfo = NULL;
+ fcinfo.context = NULL;
+ fcinfo.resultinfo = NULL;
+ fcinfo.isnull = false;
+
fcinfo.nargs = 1;
fcinfo.arg[0] = arg1;
+ fcinfo.argnull[0] = false;
result = (*func) (&fcinfo);
FunctionCallInfoData fcinfo;
Datum result;
- MemSet(&fcinfo, 0, sizeof(fcinfo));
+ /* MemSet(&fcinfo, 0, sizeof(fcinfo)); */
+ fcinfo.flinfo = NULL;
+ fcinfo.context = NULL;
+ fcinfo.resultinfo = NULL;
+ fcinfo.isnull = false;
+
fcinfo.nargs = 2;
fcinfo.arg[0] = arg1;
fcinfo.arg[1] = arg2;
+ fcinfo.argnull[0] = false;
+ fcinfo.argnull[1] = false;
result = (*func) (&fcinfo);
FunctionCallInfoData fcinfo;
Datum result;
- MemSet(&fcinfo, 0, sizeof(fcinfo));
+ /* MemSet(&fcinfo, 0, sizeof(fcinfo)); */
+ fcinfo.context = NULL;
+ fcinfo.resultinfo = NULL;
+ fcinfo.isnull = false;
+
fcinfo.flinfo = flinfo;
fcinfo.nargs = 1;
fcinfo.arg[0] = arg1;
+ fcinfo.argnull[0] = false;
result = FunctionCallInvoke(&fcinfo);
FunctionCallInfoData fcinfo;
Datum result;
- MemSet(&fcinfo, 0, sizeof(fcinfo));
+ /* MemSet(&fcinfo, 0, sizeof(fcinfo)); */
+ fcinfo.context = NULL;
+ fcinfo.resultinfo = NULL;
+ fcinfo.isnull = false;
+
fcinfo.flinfo = flinfo;
fcinfo.nargs = 2;
fcinfo.arg[0] = arg1;
fcinfo.arg[1] = arg2;
+ fcinfo.argnull[0] = false;
+ fcinfo.argnull[1] = false;
result = FunctionCallInvoke(&fcinfo);
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/sort/tuplesort.c,v 1.27 2002/09/04 20:31:33 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/sort/tuplesort.c,v 1.28 2002/10/04 17:19:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
+ * This routine selects an appropriate sorting function to implement
+ * a sort operator as efficiently as possible. The straightforward
+ * method is to use the operator's implementation proc --- ie, "<"
+ * comparison. However, that way often requires two calls of the function
+ * per comparison. If we can find a btree three-way comparator function
+ * associated with the operator, we can use it to do the comparisons
+ * more efficiently. We also support the possibility that the operator
+ * is ">" (descending sort), in which case we have to reverse the output
+ * of the btree comparator.
+ *
+ * Possibly this should live somewhere else (backend/catalog/, maybe?).
+ */
+void
+SelectSortFunction(Oid sortOperator,
+ RegProcedure *sortFunction,
+ SortFunctionKind *kind)
+{
+ Relation relation;
+ HeapScanDesc scan;
+ ScanKeyData skey[1];
+ HeapTuple tuple;
+ Form_pg_operator optup;
+ Oid opclass = InvalidOid;
+
+ /*
+ * Scan pg_amop to see if the target operator is registered as the "<"
+ * or ">" operator of any btree opclass. It's possible that it might
+ * be registered both ways (eg, if someone were to build a "reverse
+ * sort" opclass for some reason); prefer the "<" case if so. If the
+ * operator is registered the same way in multiple opclasses, assume
+ * we can use the associated comparator function from any one.
+ */
+ ScanKeyEntryInitialize(&skey[0], 0x0,
+ Anum_pg_amop_amopopr,
+ F_OIDEQ,
+ ObjectIdGetDatum(sortOperator));
+
+ relation = heap_openr(AccessMethodOperatorRelationName, AccessShareLock);
+ scan = heap_beginscan(relation, SnapshotNow, 1, skey);
+
+ while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
+ {
+ Form_pg_amop aform = (Form_pg_amop) GETSTRUCT(tuple);
+
+ if (!opclass_is_btree(aform->amopclaid))
+ continue;
+ if (aform->amopstrategy == BTLessStrategyNumber)
+ {
+ opclass = aform->amopclaid;
+ *kind = SORTFUNC_CMP;
+ break; /* done looking */
+ }
+ else if (aform->amopstrategy == BTGreaterStrategyNumber)
+ {
+ opclass = aform->amopclaid;
+ *kind = SORTFUNC_REVCMP;
+ /* keep scanning in hopes of finding a BTLess entry */
+ }
+ }
+
+ heap_endscan(scan);
+ heap_close(relation, AccessShareLock);
+
+ if (OidIsValid(opclass))
+ {
+ /* Found a suitable opclass, get its comparator support function */
+ tuple = SearchSysCache(AMPROCNUM,
+ ObjectIdGetDatum(opclass),
+ Int16GetDatum(BTORDER_PROC),
+ 0, 0);
+ if (HeapTupleIsValid(tuple))
+ {
+ Form_pg_amproc aform = (Form_pg_amproc) GETSTRUCT(tuple);
+
+ *sortFunction = aform->amproc;
+ ReleaseSysCache(tuple);
+ Assert(RegProcedureIsValid(*sortFunction));
+ return;
+ }
+ }
+
+ /*
+ * Can't find a comparator, so use the operator as-is. Decide whether
+ * it is forward or reverse sort by looking at its name (grotty, but
+ * this only matters for deciding which end NULLs should get sorted
+ * to).
+ */
+ tuple = SearchSysCache(OPEROID,
+ ObjectIdGetDatum(sortOperator),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(tuple))
+ elog(ERROR, "SelectSortFunction: cache lookup failed for operator %u",
+ sortOperator);
+ optup = (Form_pg_operator) GETSTRUCT(tuple);
+ if (strcmp(NameStr(optup->oprname), ">") == 0)
+ *kind = SORTFUNC_REVLT;
+ else
+ *kind = SORTFUNC_LT;
+ *sortFunction = optup->oprcode;
+ ReleaseSysCache(tuple);
+
+ Assert(RegProcedureIsValid(*sortFunction));
+}
+
+/*
+ * Inline-able copy of FunctionCall2() to save some cycles in sorting.
+ */
+static inline Datum
+myFunctionCall2(FmgrInfo *flinfo, Datum arg1, Datum arg2)
+{
+ FunctionCallInfoData fcinfo;
+ Datum result;
+
+ /* MemSet(&fcinfo, 0, sizeof(fcinfo)); */
+ fcinfo.context = NULL;
+ fcinfo.resultinfo = NULL;
+ fcinfo.isnull = false;
+
+ fcinfo.flinfo = flinfo;
+ fcinfo.nargs = 2;
+ fcinfo.arg[0] = arg1;
+ fcinfo.arg[1] = arg2;
+ fcinfo.argnull[0] = false;
+ fcinfo.argnull[1] = false;
+
+ result = FunctionCallInvoke(&fcinfo);
+
+ /* Check for null result, since caller is clearly not expecting one */
+ if (fcinfo.isnull)
+ elog(ERROR, "FunctionCall2: function %u returned NULL",
+ fcinfo.flinfo->fn_oid);
+
+ return result;
+}
+
+/*
+ * Apply a sort function (by now converted to fmgr lookup form)
+ * and return a 3-way comparison result. This takes care of handling
+ * NULLs and sort ordering direction properly.
+ */
+inline int32
+ApplySortFunction(FmgrInfo *sortFunction, SortFunctionKind kind,
+ Datum datum1, bool isNull1,
+ Datum datum2, bool isNull2)
+{
+ switch (kind)
+ {
+ case SORTFUNC_LT:
+ if (isNull1)
+ {
+ if (isNull2)
+ return 0;
+ return 1; /* NULL sorts after non-NULL */
+ }
+ if (isNull2)
+ return -1;
+ if (DatumGetBool(myFunctionCall2(sortFunction, datum1, datum2)))
+ return -1; /* a < b */
+ if (DatumGetBool(myFunctionCall2(sortFunction, datum2, datum1)))
+ return 1; /* a > b */
+ return 0;
+
+ case SORTFUNC_REVLT:
+ /* We reverse the ordering of NULLs, but not the operator */
+ if (isNull1)
+ {
+ if (isNull2)
+ return 0;
+ return -1; /* NULL sorts before non-NULL */
+ }
+ if (isNull2)
+ return 1;
+ if (DatumGetBool(myFunctionCall2(sortFunction, datum1, datum2)))
+ return -1; /* a < b */
+ if (DatumGetBool(myFunctionCall2(sortFunction, datum2, datum1)))
+ return 1; /* a > b */
+ return 0;
+
+ case SORTFUNC_CMP:
+ if (isNull1)
+ {
+ if (isNull2)
+ return 0;
+ return 1; /* NULL sorts after non-NULL */
+ }
+ if (isNull2)
+ return -1;
+ return DatumGetInt32(myFunctionCall2(sortFunction,
+ datum1, datum2));
+
+ case SORTFUNC_REVCMP:
+ if (isNull1)
+ {
+ if (isNull2)
+ return 0;
+ return -1; /* NULL sorts before non-NULL */
+ }
+ if (isNull2)
+ return 1;
+ return -DatumGetInt32(myFunctionCall2(sortFunction,
+ datum1, datum2));
+
+ default:
+ elog(ERROR, "Invalid SortFunctionKind %d", (int) kind);
+ return 0; /* can't get here, but keep compiler quiet */
+ }
+}
+
+
+/*
* Routines specialized for HeapTuple case
*/
MAXALIGN(sizeof(DatumTuple)));
return (void *) tuple;
}
-
-
-/*
- * This routine selects an appropriate sorting function to implement
- * a sort operator as efficiently as possible. The straightforward
- * method is to use the operator's implementation proc --- ie, "<"
- * comparison. However, that way often requires two calls of the function
- * per comparison. If we can find a btree three-way comparator function
- * associated with the operator, we can use it to do the comparisons
- * more efficiently. We also support the possibility that the operator
- * is ">" (descending sort), in which case we have to reverse the output
- * of the btree comparator.
- *
- * Possibly this should live somewhere else (backend/catalog/, maybe?).
- */
-void
-SelectSortFunction(Oid sortOperator,
- RegProcedure *sortFunction,
- SortFunctionKind *kind)
-{
- Relation relation;
- HeapScanDesc scan;
- ScanKeyData skey[1];
- HeapTuple tuple;
- Form_pg_operator optup;
- Oid opclass = InvalidOid;
-
- /*
- * Scan pg_amop to see if the target operator is registered as the "<"
- * or ">" operator of any btree opclass. It's possible that it might
- * be registered both ways (eg, if someone were to build a "reverse
- * sort" opclass for some reason); prefer the "<" case if so. If the
- * operator is registered the same way in multiple opclasses, assume
- * we can use the associated comparator function from any one.
- */
- ScanKeyEntryInitialize(&skey[0], 0x0,
- Anum_pg_amop_amopopr,
- F_OIDEQ,
- ObjectIdGetDatum(sortOperator));
-
- relation = heap_openr(AccessMethodOperatorRelationName, AccessShareLock);
- scan = heap_beginscan(relation, SnapshotNow, 1, skey);
-
- while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
- {
- Form_pg_amop aform = (Form_pg_amop) GETSTRUCT(tuple);
-
- if (!opclass_is_btree(aform->amopclaid))
- continue;
- if (aform->amopstrategy == BTLessStrategyNumber)
- {
- opclass = aform->amopclaid;
- *kind = SORTFUNC_CMP;
- break; /* done looking */
- }
- else if (aform->amopstrategy == BTGreaterStrategyNumber)
- {
- opclass = aform->amopclaid;
- *kind = SORTFUNC_REVCMP;
- /* keep scanning in hopes of finding a BTLess entry */
- }
- }
-
- heap_endscan(scan);
- heap_close(relation, AccessShareLock);
-
- if (OidIsValid(opclass))
- {
- /* Found a suitable opclass, get its comparator support function */
- tuple = SearchSysCache(AMPROCNUM,
- ObjectIdGetDatum(opclass),
- Int16GetDatum(BTORDER_PROC),
- 0, 0);
- if (HeapTupleIsValid(tuple))
- {
- Form_pg_amproc aform = (Form_pg_amproc) GETSTRUCT(tuple);
-
- *sortFunction = aform->amproc;
- ReleaseSysCache(tuple);
- Assert(RegProcedureIsValid(*sortFunction));
- return;
- }
- }
-
- /*
- * Can't find a comparator, so use the operator as-is. Decide whether
- * it is forward or reverse sort by looking at its name (grotty, but
- * this only matters for deciding which end NULLs should get sorted
- * to).
- */
- tuple = SearchSysCache(OPEROID,
- ObjectIdGetDatum(sortOperator),
- 0, 0, 0);
- if (!HeapTupleIsValid(tuple))
- elog(ERROR, "SelectSortFunction: cache lookup failed for operator %u",
- sortOperator);
- optup = (Form_pg_operator) GETSTRUCT(tuple);
- if (strcmp(NameStr(optup->oprname), ">") == 0)
- *kind = SORTFUNC_REVLT;
- else
- *kind = SORTFUNC_LT;
- *sortFunction = optup->oprcode;
- ReleaseSysCache(tuple);
-
- Assert(RegProcedureIsValid(*sortFunction));
-}
-
-/*
- * Apply a sort function (by now converted to fmgr lookup form)
- * and return a 3-way comparison result. This takes care of handling
- * NULLs and sort ordering direction properly.
- */
-int32
-ApplySortFunction(FmgrInfo *sortFunction, SortFunctionKind kind,
- Datum datum1, bool isNull1,
- Datum datum2, bool isNull2)
-{
- switch (kind)
- {
- case SORTFUNC_LT:
- if (isNull1)
- {
- if (isNull2)
- return 0;
- return 1; /* NULL sorts after non-NULL */
- }
- if (isNull2)
- return -1;
- if (DatumGetBool(FunctionCall2(sortFunction, datum1, datum2)))
- return -1; /* a < b */
- if (DatumGetBool(FunctionCall2(sortFunction, datum2, datum1)))
- return 1; /* a > b */
- return 0;
-
- case SORTFUNC_REVLT:
- /* We reverse the ordering of NULLs, but not the operator */
- if (isNull1)
- {
- if (isNull2)
- return 0;
- return -1; /* NULL sorts before non-NULL */
- }
- if (isNull2)
- return 1;
- if (DatumGetBool(FunctionCall2(sortFunction, datum1, datum2)))
- return -1; /* a < b */
- if (DatumGetBool(FunctionCall2(sortFunction, datum2, datum1)))
- return 1; /* a > b */
- return 0;
-
- case SORTFUNC_CMP:
- if (isNull1)
- {
- if (isNull2)
- return 0;
- return 1; /* NULL sorts after non-NULL */
- }
- if (isNull2)
- return -1;
- return DatumGetInt32(FunctionCall2(sortFunction,
- datum1, datum2));
-
- case SORTFUNC_REVCMP:
- if (isNull1)
- {
- if (isNull2)
- return 0;
- return -1; /* NULL sorts before non-NULL */
- }
- if (isNull2)
- return 1;
- return -DatumGetInt32(FunctionCall2(sortFunction,
- datum1, datum2));
-
- default:
- elog(ERROR, "Invalid SortFunctionKind %d", (int) kind);
- return 0; /* can't get here, but keep compiler quiet */
- }
-}
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