Move pg_constraint.h function declarations to new file pg_constraint_fn.h.

A pending patch requires exporting a function returning Bitmapset from
catalog/pg_constraint.c.  As things stand, that would mean including
nodes/bitmapset.h in pg_constraint.h, which might be hazardous for the
client-side includability of that header.  It's not entirely clear whether
any client-side code needs to include pg_constraint.h, but it seems prudent
to assume that there is some such code somewhere.  Therefore, split off the
function definitions into a new file pg_constraint_fn.h, similarly to what
we've done for some other catalog header files.

src/backend/catalog/dependency.c

@@ -28,6 +28,7 @@
 #include "catalog/pg_collation.h"
 #include "catalog/pg_collation_fn.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_conversion.h"
 #include "catalog/pg_conversion_fn.h"
 #include "catalog/pg_database.h"

src/backend/catalog/heap.c

@@ -44,6 +44,7 @@
 #include "catalog/pg_attrdef.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_foreign_table.h"
 #include "catalog/pg_inherits.h"
 #include "catalog/pg_namespace.h"

src/backend/catalog/index.c

@@ -40,6 +40,7 @@
 #include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_opclass.h"
 #include "catalog/pg_tablespace.h"

src/backend/catalog/objectaddress.c

@@ -30,6 +30,7 @@
 #include "catalog/pg_event_trigger.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_conversion.h"
 #include "catalog/pg_database.h"
 #include "catalog/pg_extension.h"

src/backend/catalog/pg_constraint.c

@@ -21,6 +21,7 @@
 #include "catalog/indexing.h"
 #include "catalog/objectaccess.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"

src/backend/commands/tablecmds.c

@@ -32,6 +32,7 @@
 #include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_depend.h"
 #include "catalog/pg_foreign_table.h"
 #include "catalog/pg_inherits.h"

src/backend/commands/trigger.c

@@ -23,6 +23,7 @@
 #include "catalog/indexing.h"
 #include "catalog/objectaccess.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_trigger.h"
 #include "catalog/pg_type.h"

src/backend/commands/typecmds.c

@@ -41,6 +41,7 @@
 #include "catalog/pg_authid.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_depend.h"
 #include "catalog/pg_enum.h"
 #include "catalog/pg_language.h"

src/backend/parser/parse_agg.c

@@ -15,7 +15,7 @@
 #include "postgres.h"
 
 #include "catalog/pg_aggregate.h"
-#include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_type.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"

src/backend/parser/parse_clause.c

@@ -22,7 +22,7 @@
 #include "catalog/catalog.h"
 #include "catalog/heap.h"
 #include "catalog/pg_am.h"
-#include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"
 #include "nodes/makefuncs.h"

src/backend/parser/parse_utilcmd.c

@@ -36,6 +36,7 @@
 #include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
+#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_opclass.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_type.h"

src/include/catalog/pg_constraint.h

@@ -20,8 +20,6 @@
 #define PG_CONSTRAINT_H
 
 #include "catalog/genbki.h"
-#include "catalog/dependency.h"
-#include "nodes/pg_list.h"
 
 /* ----------------
  *		pg_constraint definition.  cpp turns this into
@@ -178,6 +176,13 @@ typedef FormData_pg_constraint *Form_pg_constraint;
 #define Anum_pg_constraint_conbin			23
 #define Anum_pg_constraint_consrc			24
 
+/* ----------------
+ *		initial contents of pg_constraint
+ * ----------------
+ */
+
+/* nothing, at present */
+
 
 /* Valid values for contype */
 #define CONSTRAINT_CHECK			'c'
@@ -193,66 +198,4 @@ typedef FormData_pg_constraint *Form_pg_constraint;
  * the FKCONSTR_MATCH_xxx constants defined in parsenodes.h.
  */
 
-/*
- * Identify constraint type for lookup purposes
- */
-typedef enum ConstraintCategory
-{
-	CONSTRAINT_RELATION,
-	CONSTRAINT_DOMAIN,
-	CONSTRAINT_ASSERTION		/* for future expansion */
-} ConstraintCategory;
-
-/*
- * prototypes for functions in pg_constraint.c
- */
-extern Oid CreateConstraintEntry(const char *constraintName,
-					  Oid constraintNamespace,
-					  char constraintType,
-					  bool isDeferrable,
-					  bool isDeferred,
-					  bool isValidated,
-					  Oid relId,
-					  const int16 *constraintKey,
-					  int constraintNKeys,
-					  Oid domainId,
-					  Oid indexRelId,
-					  Oid foreignRelId,
-					  const int16 *foreignKey,
-					  const Oid *pfEqOp,
-					  const Oid *ppEqOp,
-					  const Oid *ffEqOp,
-					  int foreignNKeys,
-					  char foreignUpdateType,
-					  char foreignDeleteType,
-					  char foreignMatchType,
-					  const Oid *exclOp,
-					  Node *conExpr,
-					  const char *conBin,
-					  const char *conSrc,
-					  bool conIsLocal,
-					  int conInhCount,
-					  bool conNoInherit,
-					  bool is_internal);
-
-extern void RemoveConstraintById(Oid conId);
-extern void RenameConstraintById(Oid conId, const char *newname);
-extern void SetValidatedConstraintById(Oid conId);
-
-extern bool ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
-					 Oid objNamespace, const char *conname);
-extern char *ChooseConstraintName(const char *name1, const char *name2,
-					 const char *label, Oid namespaceid,
-					 List *others);
-
-extern void AlterConstraintNamespaces(Oid ownerId, Oid oldNspId,
-					  Oid newNspId, bool isType, ObjectAddresses *objsMoved);
-extern Oid	get_relation_constraint_oid(Oid relid, const char *conname, bool missing_ok);
-extern Oid	get_domain_constraint_oid(Oid typid, const char *conname, bool missing_ok);
-
-extern bool check_functional_grouping(Oid relid,
-						  Index varno, Index varlevelsup,
-						  List *grouping_columns,
-						  List **constraintDeps);
-
 #endif   /* PG_CONSTRAINT_H */

src/include/catalog/pg_constraint_fn.h

+/*-------------------------------------------------------------------------
+ *
+ * pg_constraint_fn.h
+ *	 prototypes for functions in catalog/pg_constraint.c
+ *
+ *
+ * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/catalog/pg_constraint_fn.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PG_CONSTRAINT_FN_H
+#define PG_CONSTRAINT_FN_H
+
+#include "catalog/dependency.h"
+#include "nodes/pg_list.h"
+
+/*
+ * Identify constraint type for lookup purposes
+ */
+typedef enum ConstraintCategory
+{
+	CONSTRAINT_RELATION,
+	CONSTRAINT_DOMAIN,
+	CONSTRAINT_ASSERTION		/* for future expansion */
+} ConstraintCategory;
+
+extern Oid CreateConstraintEntry(const char *constraintName,
+					  Oid constraintNamespace,
+					  char constraintType,
+					  bool isDeferrable,
+					  bool isDeferred,
+					  bool isValidated,
+					  Oid relId,
+					  const int16 *constraintKey,
+					  int constraintNKeys,
+					  Oid domainId,
+					  Oid indexRelId,
+					  Oid foreignRelId,
+					  const int16 *foreignKey,
+					  const Oid *pfEqOp,
+					  const Oid *ppEqOp,
+					  const Oid *ffEqOp,
+					  int foreignNKeys,
+					  char foreignUpdateType,
+					  char foreignDeleteType,
+					  char foreignMatchType,
+					  const Oid *exclOp,
+					  Node *conExpr,
+					  const char *conBin,
+					  const char *conSrc,
+					  bool conIsLocal,
+					  int conInhCount,
+					  bool conNoInherit,
+					  bool is_internal);
+
+extern void RemoveConstraintById(Oid conId);
+extern void RenameConstraintById(Oid conId, const char *newname);
+extern void SetValidatedConstraintById(Oid conId);
+
+extern bool ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
+					 Oid objNamespace, const char *conname);
+extern char *ChooseConstraintName(const char *name1, const char *name2,
+					 const char *label, Oid namespaceid,
+					 List *others);
+
+extern void AlterConstraintNamespaces(Oid ownerId, Oid oldNspId,
+					  Oid newNspId, bool isType, ObjectAddresses *objsMoved);
+extern Oid	get_relation_constraint_oid(Oid relid, const char *conname, bool missing_ok);
+extern Oid	get_domain_constraint_oid(Oid typid, const char *conname, bool missing_ok);
+
+extern bool check_functional_grouping(Oid relid,
+						  Index varno, Index varlevelsup,
+						  List *grouping_columns,
+						  List **constraintDeps);
+
+#endif   /* PG_CONSTRAINT_FN_H */