Tweak the API for per-datatype typmodin functions so that they are passed

an array of strings rather than an array of integers, and allow any simple
constant or identifier to be used in typmods; for example
	create table foo (f1 widget(42,'23skidoo',point));
Of course the typmodin function has still got to pack this info into a
non-negative int32 for storage, but it's still a useful improvement in
flexibility, especially considering that you can do nearly anything if you
are willing to keep the info in a side table.  We can get away with this
change since we have not yet released a version providing user-definable
typmods.  Per discussion.

Author: tglsfdc

doc/src/sgml/ref/create_type.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/create_type.sgml,v 1.71 2007/05/12 00:54:59 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_type.sgml,v 1.72 2007/06/15 20:56:49 tgl Exp $
 PostgreSQL documentation
 -->
 
@@ -195,11 +195,11 @@ CREATE TYPE <replaceable class="parameter">name</replaceable>
    are needed if the type supports modifiers, that is optional constraints
    attached to a type declaration, such as <literal>char(5)</> or
    <literal>numeric(30,2)</>.  <productname>PostgreSQL</productname> allows
-   user-defined types to take one or more integer constants as modifiers;
-   however, this information must be capable of being packed into a single
-   non-negative integer value for storage in the system catalogs.  The
+   user-defined types to take one or more simple constants or identifiers as
+   modifiers; however, this information must be capable of being packed into a
+   single non-negative integer value for storage in the system catalogs.  The
    <replaceable class="parameter">type_modifier_input_function</replaceable>
-   is passed the declared modifier(s) in the form of an <type>integer</>
+   is passed the declared modifier(s) in the form of a <type>cstring</>
    array.  It must check the values for validity (throwing an error if they
    are wrong), and if they are correct, return a single non-negative
    <type>integer</> value that will be stored as the column <quote>typmod</>.

src/backend/commands/typecmds.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/typecmds.c,v 1.104 2007/05/12 00:54:59 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/typecmds.c,v 1.105 2007/06/15 20:56:49 tgl Exp $
  *
  * DESCRIPTION
  *	  The "DefineFoo" routines take the parse tree and pick out the
@@ -1270,9 +1270,9 @@ findTypeTypmodinFunction(List *procname)
 	Oid			procOid;
 
 	/*
-	 * typmodin functions always take one int4[] argument and return int4.
+	 * typmodin functions always take one cstring[] argument and return int4.
 	 */
-	argList[0] = INT4ARRAYOID;
+	argList[0] = CSTRINGARRAYOID;
 
 	procOid = LookupFuncName(procname, 1, argList, true);
 	if (!OidIsValid(procOid))

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.593 2007/06/11 22:22:41 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.594 2007/06/15 20:56:49 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -6695,7 +6695,7 @@ ConstTypename:
  * by the standard, including qualified names.  We also allow type modifiers.
  * To avoid parsing conflicts against function invocations, the modifiers
  * have to be shown as expr_list here, but parse analysis will only accept
- * integer constants for them.
+ * constants for them.
  */
 GenericType:
 			type_function_name opt_type_modifiers

src/backend/parser/parse_type.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_type.c,v 1.90 2007/05/11 17:57:12 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_type.c,v 1.91 2007/06/15 20:56:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -289,28 +289,55 @@ typenameTypeMod(ParseState *pstate, const TypeName *typename,
 				 parser_errposition(pstate, typename->location)));
 
 	/*
-	 * Convert the list of (raw grammar output) expressions to an integer
-	 * array.  Currently, we only allow simple integer constants, though
-	 * possibly this could be extended.
+	 * Convert the list of raw-grammar-output expressions to a cstring array.
+	 * Currently, we allow simple numeric constants, string literals, and
+	 * identifiers; possibly this list could be extended.
 	 */
 	datums = (Datum *) palloc(list_length(typename->typmods) * sizeof(Datum));
 	n = 0;
 	foreach(l, typename->typmods)
 	{
-		A_Const	*ac = (A_Const *) lfirst(l);
+		Node	*tm = (Node *) lfirst(l);
+		char	*cstr = NULL;
 
-		if (!IsA(ac, A_Const) ||
-			!IsA(&ac->val, Integer))
+		if (IsA(tm, A_Const))
+		{
+			A_Const	   *ac = (A_Const *) tm;
+
+			/*
+			 * The grammar hands back some integers with ::int4 attached,
+			 * so allow a cast decoration if it's an Integer value, but
+			 * not otherwise.
+			 */
+			if (IsA(&ac->val, Integer))
+			{
+				cstr = (char *) palloc(32);
+				snprintf(cstr, 32, "%ld", (long) ac->val.val.ival);
+			}
+			else if (ac->typename == NULL)	/* no casts allowed */
+			{
+				/* otherwise we can just use the str field directly. */
+				cstr = ac->val.val.str;
+			}
+		}
+		else if (IsA(tm, ColumnRef))
+		{
+			ColumnRef   *cr = (ColumnRef *) tm;
+
+			if (list_length(cr->fields) == 1)
+				cstr = strVal(linitial(cr->fields));
+		}
+		if (!cstr)
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
-					 errmsg("type modifiers must be integer constants"),
+					 errmsg("type modifiers must be simple constants or identifiers"),
 					 parser_errposition(pstate, typename->location)));
-		datums[n++] = Int32GetDatum(ac->val.val.ival);
+		datums[n++] = CStringGetDatum(cstr);
 	}
 
-	/* hardwired knowledge about int4's representation details here */
-	arrtypmod = construct_array(datums, n, INT4OID,
-								sizeof(int4), true, 'i');
+	/* hardwired knowledge about cstring's representation details here */
+	arrtypmod = construct_array(datums, n, CSTRINGOID,
+								-2, false, 'c');
 
 	result = DatumGetInt32(OidFunctionCall1(typmodin,
 											PointerGetDatum(arrtypmod)));

src/backend/utils/adt/arrayutils.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/arrayutils.c,v 1.23 2007/01/05 22:19:40 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/arrayutils.c,v 1.24 2007/06/15 20:56:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -17,6 +17,7 @@
 
 #include "catalog/pg_type.h"
 #include "utils/array.h"
+#include "utils/builtins.h"
 #include "utils/memutils.h"
 
 
@@ -191,16 +192,21 @@ mda_next_tuple(int n, int *curr, const int *span)
 }
 
 /*
- * ArrayGetTypmods: verify that argument is a 1-D integer array,
- * return its length and a pointer to the first contained integer.
+ * ArrayGetIntegerTypmods: verify that argument is a 1-D cstring array,
+ * and get the contents converted to integers.  Returns a palloc'd array
+ * and places the length at *n.
  */
 int32 *
-ArrayGetTypmods(ArrayType *arr, int *n)
+ArrayGetIntegerTypmods(ArrayType *arr, int *n)
 {
-	if (ARR_ELEMTYPE(arr) != INT4OID)
+	int32	   *result;
+	Datum	   *elem_values;
+	int			i;
+
+	if (ARR_ELEMTYPE(arr) != CSTRINGOID)
 		ereport(ERROR,
 				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
-				 errmsg("typmod array must be type integer[]")));
+				 errmsg("typmod array must be type cstring[]")));
 
 	if (ARR_NDIM(arr) != 1)
 		ereport(ERROR,
@@ -212,7 +218,18 @@ ArrayGetTypmods(ArrayType *arr, int *n)
 				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
 				 errmsg("typmod array must not contain nulls")));
 
-	*n = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
+	/* hardwired knowledge about cstring's representation details here */
+	deconstruct_array(arr, CSTRINGOID,
+					  -2, false, 'c',
+					  &elem_values, NULL, n);
+
+	result = (int32 *) palloc(*n * sizeof(int32));
+
+	for (i = 0; i < *n; i++)
+		result[i] = pg_atoi(DatumGetCString(elem_values[i]),
+							sizeof(int32), '\0');
+
+	pfree(elem_values);
 
-	return (int32 *) ARR_DATA_PTR(arr);
+	return result;
 }

src/backend/utils/adt/date.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.132 2007/06/05 21:31:06 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.133 2007/06/15 20:56:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,7 +53,7 @@ anytime_typmodin(bool istz, ArrayType *ta)
 	int32	*tl;
 	int		n;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	/*
 	 * we're not too tense about good error message here because grammar

src/backend/utils/adt/numeric.c

@@ -14,7 +14,7 @@
  * Copyright (c) 1998-2007, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/numeric.c,v 1.104 2007/06/09 15:52:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/numeric.c,v 1.105 2007/06/15 20:56:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -547,7 +547,7 @@ numerictypmodin(PG_FUNCTION_ARGS)
 	int			n;
 	int32		typmod;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	if (n == 2)
 	{

src/backend/utils/adt/timestamp.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.177 2007/06/05 21:31:06 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.178 2007/06/15 20:56:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,7 +64,7 @@ anytimestamp_typmodin(bool istz, ArrayType *ta)
 	int32    *tl;
 	int		n;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	/*
 	 * we're not too tense about good error message here because grammar
@@ -719,7 +719,7 @@ intervaltypmodin(PG_FUNCTION_ARGS)
     int    		n;
 	int32		typmod;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	/*
 	 * tl[0] - opt_interval

src/backend/utils/adt/varbit.c

@@ -9,7 +9,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/varbit.c,v 1.53 2007/02/27 23:48:09 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/varbit.c,v 1.54 2007/06/15 20:56:51 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -32,7 +32,7 @@ anybit_typmodin(ArrayType *ta, const char *typename)
 	int32	*tl;
 	int		n;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	/*
 	 * we're not too tense about good error message here because grammar

src/backend/utils/adt/varchar.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/varchar.c,v 1.123 2007/04/06 04:21:43 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/varchar.c,v 1.124 2007/06/15 20:56:51 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -31,7 +31,7 @@ anychar_typmodin(ArrayType *ta, const char *typename)
 	int32	*tl;
 	int		n;
 
-	tl = ArrayGetTypmods(ta, &n);
+	tl = ArrayGetIntegerTypmods(ta, &n);
 
 	/*
 	 * we're not too tense about good error message here because grammar

src/include/catalog/catversion.h

@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.411 2007/06/06 23:00:40 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.412 2007/06/15 20:56:51 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200706061
+#define CATALOG_VERSION_NO	200706151
 
 #endif