Fix handling of pg_type.typdefault per bug report from Dave Blasby.

If there's anyone out there who's actually using datatype-defined
default values, this will be an incompatible change in behavior ...
but the old behavior was so broken that I doubt anyone was using it.

Author: tglsfdc

doc/src/sgml/catalogs.sgml

@@ -1,6 +1,6 @@
 <!--
  Documentation of the system catalogs, directed toward PostgreSQL developers
- $Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.22 2001/08/26 16:55:58 tgl Exp $
+ $Header: /cvsroot/pgsql/doc/src/sgml/catalogs.sgml,v 2.23 2001/09/06 02:07:41 tgl Exp $
  -->
 
 <chapter id="catalogs">
@@ -243,7 +243,9 @@
       <entry></entry>
       <entry>
        The initial value of the transition state.  This is a text
-       field which will be cast to the type of aggtranstype.
+       field containing the initial value in its external string
+       representation.  If the field is NULL, the transition state
+       value starts out NULL.
       </entry>
      </row>
     </tbody>
@@ -2071,7 +2073,11 @@
       <entry>typdefault</entry>
       <entry><type>text</type></entry>
       <entry></entry>
-      <entry>???</entry>
+      <entry><para>
+       <structfield>typdefault</structfield> is NULL for types without a
+       default value.  If it's not NULL, it contains the external string
+       representation of the type's default value.
+      </para></entry>
      </row>
     </tbody>
    </tgroup>

src/backend/catalog/heap.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.175 2001/08/25 18:52:41 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.176 2001/09/06 02:07:42 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -657,7 +657,6 @@ AddNewRelationTuple(Relation pg_class_desc,
 static void
 AddNewRelationType(char *typeName, Oid new_rel_oid, Oid new_type_oid)
 {
-
 	/*
 	 * The sizes are set to oid size because it makes implementing sets
 	 * MUCH easier, and no one (we hope) uses these fields to figure out
@@ -666,24 +665,22 @@ AddNewRelationType(char *typeName, Oid new_rel_oid, Oid new_type_oid)
 	 * actually get is the oid of a tuple in the pg_proc catalog, so the
 	 * size of the "set" is the size of an oid. Similarly, byval being
 	 * true makes sets much easier, and it isn't used by anything else.
-	 *
-	 * XXX Note the assumption that OIDs are the same size as int4s.
 	 */
 	TypeCreate(typeName,		/* type name */
 			   new_type_oid,	/* preassigned oid for type */
 			   new_rel_oid,		/* relation oid */
 			   sizeof(Oid),		/* internal size */
-			   sizeof(Oid),		/* external size */
+			   -1,				/* external size */
 			   'c',				/* type-type (catalog) */
 			   ',',				/* default array delimiter */
-			   "int4in",		/* input procedure */
-			   "int4out",		/* output procedure */
-			   "int4in",		/* receive procedure */
-			   "int4out",		/* send procedure */
+			   "oidin",			/* input procedure */
+			   "oidout",		/* output procedure */
+			   "oidin",			/* receive procedure */
+			   "oidout",		/* send procedure */
 			   NULL,			/* array element type - irrelevant */
-			   "-",				/* default type value */
+			   NULL,			/* default type value - none */
 			   true,			/* passed by value */
-			   'i',				/* default alignment */
+			   'i',				/* default alignment - same as for OID */
 			   'p');			/* Not TOASTable */
 }
 

src/backend/catalog/pg_type.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_type.c,v 1.62 2001/08/10 15:49:39 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_type.c,v 1.63 2001/09/06 02:07:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -51,7 +51,7 @@ TypeGetWithOpenRelation(Relation pg_type_desc,
 	/*
 	 * initialize the scan key and begin a scan of pg_type
 	 */
-	ScanKeyEntryInitialize(typeKey,
+	ScanKeyEntryInitialize(&typeKey[0],
 						   0,
 						   Anum_pg_type_typname,
 						   F_NAMEEQ,
@@ -318,10 +318,18 @@ TypeCreate(char *typeName,
 	}
 
 	/*
-	 * XXX comment me
+	 * validate size specifications: either positive (fixed-length) or
+	 * -1 (variable-length).
 	 */
-	if (externalSize == 0)
-		externalSize = -1;		/* variable length */
+	if (! (internalSize > 0 || internalSize == -1))
+		elog(ERROR, "TypeCreate: invalid type internal size %d",
+			 internalSize);
+	if (! (externalSize > 0 || externalSize == -1))
+		elog(ERROR, "TypeCreate: invalid type external size %d",
+			 externalSize);
+
+	if (internalSize != -1 && storage != 'p')
+		elog(ERROR, "TypeCreate: fixed size types must have storage PLAIN");
 
 	/*
 	 * initialize arrays needed by FormHeapTuple
@@ -330,20 +338,9 @@ TypeCreate(char *typeName,
 	{
 		nulls[i] = ' ';
 		replaces[i] = 'r';
-		values[i] = (Datum) NULL;		/* redundant, but nice */
+		values[i] = (Datum) 0;
 	}
 
-	/*
-	 * XXX
-	 *
-	 * Do this so that user-defined types have size -1 instead of zero if
-	 * they are variable-length - this is so that everything else in the
-	 * backend works.
-	 */
-
-	if (internalSize == 0)
-		internalSize = -1;
-
 	/*
 	 * initialize the *values information
 	 */
@@ -435,15 +432,19 @@ TypeCreate(char *typeName,
 	/*
 	 * initialize the default value for this type.
 	 */
-	values[i] = DirectFunctionCall1(textin,		/* 17 */
-			 CStringGetDatum(defaultTypeValue ? defaultTypeValue : "-"));
+	if (defaultTypeValue)
+		values[i] = DirectFunctionCall1(textin,
+										CStringGetDatum(defaultTypeValue));
+	else
+		nulls[i] = 'n';
+	i++;						/* 17 */
 
 	/*
 	 * open pg_type and begin a scan for the type name.
 	 */
 	pg_type_desc = heap_openr(TypeRelationName, RowExclusiveLock);
 
-	ScanKeyEntryInitialize(typeKey,
+	ScanKeyEntryInitialize(&typeKey[0],
 						   0,
 						   Anum_pg_type_typname,
 						   F_NAMEEQ,

src/backend/commands/define.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/define.c,v 1.58 2001/08/03 20:47:40 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/define.c,v 1.59 2001/09/06 02:07:42 tgl Exp $
  *
  * DESCRIPTION
  *	  The "DefineFoo" routines take the parse tree and pick out the
@@ -535,31 +535,29 @@ DefineAggregate(char *aggName, List *parameters)
 void
 DefineType(char *typeName, List *parameters)
 {
-	int16		internalLength = 0;		/* int2 */
-	int16		externalLength = 0;		/* int2 */
+	int16		internalLength = -1;		/* int2 */
+	int16		externalLength = -1;		/* int2 */
 	char	   *elemName = NULL;
 	char	   *inputName = NULL;
 	char	   *outputName = NULL;
 	char	   *sendName = NULL;
 	char	   *receiveName = NULL;
-	char	   *defaultValue = NULL;	/* Datum */
+	char	   *defaultValue = NULL;
 	bool		byValue = false;
 	char		delimiter = DEFAULT_TYPDELIM;
 	char	   *shadow_type;
 	List	   *pl;
 	char		alignment = 'i'; /* default alignment */
-	char		storage = 'p';	/* default storage in TOAST */
+	char		storage = 'p';	/* default TOAST storage method */
 
 	/*
 	 * Type names must be one character shorter than other names, allowing
 	 * room to create the corresponding array type name with prepended
 	 * "_".
 	 */
 	if (strlen(typeName) > (NAMEDATALEN - 2))
-	{
 		elog(ERROR, "DefineType: type names must be %d characters or less",
 			 NAMEDATALEN - 2);
-	}
 
 	foreach(pl, parameters)
 	{
@@ -645,9 +643,6 @@ DefineType(char *typeName, List *parameters)
 	if (outputName == NULL)
 		elog(ERROR, "Define: \"output\" unspecified");
 
-	if (internalLength != -1 && storage != 'p')
-		elog(ERROR, "Define: fixed size types must have storage PLAIN");
-
 	/*
 	 * now have TypeCreate do all the real work.
 	 */
@@ -674,6 +669,9 @@ DefineType(char *typeName, List *parameters)
 	 */
 	shadow_type = makeArrayTypeName(typeName);
 
+	/* alignment must be 'i' or 'd' for arrays */
+	alignment = (alignment == 'd') ? 'd' : 'i';
+
 	TypeCreate(shadow_type,		/* type name */
 			   InvalidOid,		/* preassigned type oid (not done here) */
 			   InvalidOid,		/* relation oid (n/a here) */
@@ -688,7 +686,7 @@ DefineType(char *typeName, List *parameters)
 			   typeName,		/* element type name */
 			   NULL,			/* never a default type value */
 			   false,			/* never passed by value */
-			   alignment,		/* NB: must be 'i' or 'd' for arrays... */
+			   alignment,		/* see above */
 			   'x');			/* ARRAY is always toastable */
 
 	pfree(shadow_type);

src/backend/optimizer/prep/preptlist.c

@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/prep/preptlist.c,v 1.42 2001/03/22 03:59:38 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/prep/preptlist.c,v 1.43 2001/09/06 02:07:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -192,45 +192,54 @@ expand_targetlist(List *tlist, int command_type,
 			{
 				case CMD_INSERT:
 					{
-						Datum		typedefault = get_typdefault(atttype);
-						int			typlen;
-						Const	   *temp_const;
+						bool		hasdefault;
+						Datum		typedefault;
+						int16		typlen;
+						bool		typbyval;
+						Const	   *def_const;
 
-#ifdef	_DROP_COLUMN_HACK__
-						if (COLUMN_IS_DROPPED(att_tup))
-							typedefault = PointerGetDatum(NULL);
-#endif	 /* _DROP_COLUMN_HACK__ */
-
-						if (typedefault == PointerGetDatum(NULL))
-							typlen = 0;
-						else
+						if (att_tup->attisset)
 						{
-
 							/*
-							 * Since this is an append or replace, the
-							 * size of any set attribute is the size of
-							 * the OID used to represent it.
+							 * Set attributes are represented as OIDs no
+							 * matter what the set element type is, and
+							 * the element type's default is irrelevant too.
 							 */
-							if (att_tup->attisset)
-								typlen = get_typlen(OIDOID);
+							hasdefault = false;
+							typedefault = (Datum) 0;
+							typlen = sizeof(Oid);
+							typbyval = true;
+						}
+						else
+						{
+#ifdef	_DROP_COLUMN_HACK__
+							if (COLUMN_IS_DROPPED(att_tup))
+							{
+								hasdefault = false;
+								typedefault = (Datum) 0;
+							}
 							else
-								typlen = get_typlen(atttype);
+#endif	 /* _DROP_COLUMN_HACK__ */
+								hasdefault = get_typdefault(atttype,
+															&typedefault);
+
+							get_typlenbyval(atttype, &typlen, &typbyval);
 						}
 
-						temp_const = makeConst(atttype,
-											   typlen,
-											   typedefault,
-								  (typedefault == PointerGetDatum(NULL)),
-											   false,
-											   false,	/* not a set */
-											   false);
+						def_const = makeConst(atttype,
+											  typlen,
+											  typedefault,
+											  !hasdefault,
+											  typbyval,
+											  false,	/* not a set */
+											  false);
 
 						new_tle = makeTargetEntry(makeResdom(attrno,
 															 atttype,
 															 -1,
 													   pstrdup(attrname),
 															 false),
-												  (Node *) temp_const);
+												  (Node *) def_const);
 						break;
 					}
 				case CMD_UPDATE: