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Fix portability problems recently exposed by regression tests on Alphas.

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1. Distinguish cases where a Datum representing a tuple datatype is an OID
from cases where it is a pointer to TupleTableSlot, and make sure we use
the right typlen in each case.
2. Make fetchatt() and related code support 8-byte by-value datatypes on
machines where Datum is 8 bytes.  Centralize knowledge of the available
by-value datatype sizes in two macros in tupmacs.h, so that this will be
easier if we ever have to do it again.
This commit is contained in:
Tom Lane
2000-12-27 23:59:14 +00:00
parent 97799fc475
commit 8609d4abf2
23 changed files with 497 additions and 660 deletions
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84
src/backend/access/common/tupdesc.c
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@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.69 2000/11/16 22:30:15 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.70 2000/12/27 23:59:10 tgl Exp $
*
* NOTES
* some of the executor utility code such as "ExecTypeFromTL" should be
@@ -352,7 +352,6 @@ TupleDescInitEntry(TupleDesc desc,
AssertArg(!PointerIsValid(desc->attrs[attributeNumber - 1]));
/* ----------------
* allocate storage for this attribute
* ----------------
@@ -362,7 +361,7 @@ TupleDescInitEntry(TupleDesc desc,
desc->attrs[attributeNumber - 1] = att;
/* ----------------
* initialize some of the attribute fields
* initialize the attribute fields
* ----------------
*/
att->attrelid = 0; /* dummy value */
@@ -372,7 +371,6 @@ TupleDescInitEntry(TupleDesc desc,
else
MemSet(NameStr(att->attname), 0, NAMEDATALEN);
att->attdispersion = 0; /* dummy value */
att->attcacheoff = -1;
att->atttypmod = typmod;
@@ -414,8 +412,8 @@ TupleDescInitEntry(TupleDesc desc,
att->atttypid = InvalidOid;
att->attlen = (int16) 0;
att->attbyval = (bool) 0;
att->attstorage = 'p';
att->attalign = 'i';
att->attstorage = 'p';
return false;
}
@@ -427,42 +425,63 @@ TupleDescInitEntry(TupleDesc desc,
typeForm = (Form_pg_type) GETSTRUCT(tuple);
att->atttypid = tuple->t_data->t_oid;
att->attalign = typeForm->typalign;
/* ------------------------
If this attribute is a set, what is really stored in the
attribute is the OID of a tuple in the pg_proc catalog.
The pg_proc tuple contains the query string which defines
this set - i.e., the query to run to get the set.
So the atttypid (just assigned above) refers to the type returned
by this query, but the actual length of this attribute is the
length (size) of an OID.
Why not just make the atttypid point to the OID type, instead
of the type the query returns? Because the executor uses the atttypid
to tell the front end what type will be returned (in BeginCommand),
and in the end the type returned will be the result of the query, not
an OID.
Why not wait until the return type of the set is known (i.e., the
recursive call to the executor to execute the set has returned)
before telling the front end what the return type will be? Because
the executor is a delicate thing, and making sure that the correct
order of front-end commands is maintained is messy, especially
considering that target lists may change as inherited attributes
are considered, etc. Ugh.
-----------------------------------------
*/
/*------------------------
* There are a couple of cases where we must override the information
* stored in pg_type.
*
* First: if this attribute is a set, what is really stored in the
* attribute is the OID of a tuple in the pg_proc catalog.
* The pg_proc tuple contains the query string which defines
* this set - i.e., the query to run to get the set.
* So the atttypid (just assigned above) refers to the type returned
* by this query, but the actual length of this attribute is the
* length (size) of an OID.
*
* (Why not just make the atttypid point to the OID type, instead
* of the type the query returns? Because the executor uses the atttypid
* to tell the front end what type will be returned (in BeginCommand),
* and in the end the type returned will be the result of the query, not
* an OID.)
*
* (Why not wait until the return type of the set is known (i.e., the
* recursive call to the executor to execute the set has returned)
* before telling the front end what the return type will be? Because
* the executor is a delicate thing, and making sure that the correct
* order of front-end commands is maintained is messy, especially
* considering that target lists may change as inherited attributes
* are considered, etc. Ugh.)
*
* Second: if we are dealing with a complex type (a tuple type), then
* pg_type will say that the representation is the same as Oid. But
* if typmod is sizeof(Pointer) then the internal representation is
* actually a pointer to a TupleTableSlot, and we have to substitute
* that information.
*
* A set of complex type is first and foremost a set, so its
* representation is Oid not pointer. So, test that case first.
*-----------------------------------------
*/
if (attisset)
{
att->attlen = sizeof(Oid);
att->attbyval = true;
att->attalign = 'i';
att->attstorage = 'p';
}
else if (typeForm->typtype == 'c' && typmod == sizeof(Pointer))
{
att->attlen = sizeof(Pointer);
att->attbyval = true;
att->attalign = 'd'; /* kluge to work with 8-byte pointers */
/* XXX ought to have a separate attalign value for pointers ... */
att->attstorage = 'p';
}
else
{
att->attlen = typeForm->typlen;
att->attbyval = typeForm->typbyval;
att->attalign = typeForm->typalign;
att->attstorage = typeForm->typstorage;
}
@@ -494,6 +513,7 @@ TupleDescMakeSelfReference(TupleDesc desc,
att->atttypid = TypeShellMake(relname);
att->attlen = sizeof(Oid);
att->attbyval = true;
att->attalign = 'i';
att->attstorage = 'p';
att->attnelems = 0;
}
@@ -582,15 +602,13 @@ BuildDescForRelation(List *schema, char *relname)
* have a self reference, otherwise it's an error.
* ----------------
*/
if (!strcmp(typename, relname))
if (strcmp(typename, relname) == 0)
TupleDescMakeSelfReference(desc, attnum, relname);
else
elog(ERROR, "DefineRelation: no such type %s",
typename);
}
desc->attrs[attnum - 1]->atttypmod = entry->typename->typmod;
/* This is for constraints */
if (entry->is_not_null)
constr->has_not_null = true;