Create the catalog infrastructure for foreign-data-wrapper handlers.

Add a fdwhandler column to pg_foreign_data_wrapper, plus HANDLER options
in the CREATE FOREIGN DATA WRAPPER and ALTER FOREIGN DATA WRAPPER commands,
plus pg_dump support for same.  Also invent a new pseudotype fdw_handler
with properties similar to language_handler.

This is split out of the "FDW API" patch for ease of review; it's all stuff
we will certainly need, regardless of any other details of the FDW API.
FDW handler functions will not actually get called yet.

In passing, fix some omissions and infelicities in foreigncmds.c.

Shigeru Hanada, Jan Urbanski, Heikki Linnakangas

7 files changed, 20 insertions, 10 deletions

diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 1a7be47fab8..989138169a9 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201102181
+#define CATALOG_VERSION_NO	201102191
 
 #endif
diff --git a/src/include/catalog/pg_foreign_data_wrapper.h b/src/include/catalog/pg_foreign_data_wrapper.h
index a83556df151..10afb370fd7 100644
--- a/src/include/catalog/pg_foreign_data_wrapper.h
+++ b/src/include/catalog/pg_foreign_data_wrapper.h
@@ -32,7 +32,8 @@ CATALOG(pg_foreign_data_wrapper,2328)
 {
 	NameData	fdwname;		/* foreign-data wrapper name */
 	Oid			fdwowner;		/* FDW owner */
-	Oid			fdwvalidator;	/* optional validation function */
+	Oid			fdwhandler;		/* handler function, or 0 if none */
+	Oid			fdwvalidator;	/* option validation function, or 0 if none */
 
 	/* VARIABLE LENGTH FIELDS start here. */
 
@@ -52,11 +53,12 @@ typedef FormData_pg_foreign_data_wrapper *Form_pg_foreign_data_wrapper;
  * ----------------
  */
 
-#define Natts_pg_foreign_data_wrapper				5
+#define Natts_pg_foreign_data_wrapper				6
 #define Anum_pg_foreign_data_wrapper_fdwname		1
 #define Anum_pg_foreign_data_wrapper_fdwowner		2
-#define Anum_pg_foreign_data_wrapper_fdwvalidator	3
-#define Anum_pg_foreign_data_wrapper_fdwacl			4
-#define Anum_pg_foreign_data_wrapper_fdwoptions		5
+#define Anum_pg_foreign_data_wrapper_fdwhandler		3
+#define Anum_pg_foreign_data_wrapper_fdwvalidator	4
+#define Anum_pg_foreign_data_wrapper_fdwacl			5
+#define Anum_pg_foreign_data_wrapper_fdwoptions		6
 
 #endif   /* PG_FOREIGN_DATA_WRAPPER_H */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index b3458ed56eb..08949853f19 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -3913,6 +3913,10 @@ DATA(insert OID = 2777 (  anynonarray_in	PGNSP PGUID 12 1 0 0 f f f t f i 1 0 27
 DESCR("I/O");
 DATA(insert OID = 2778 (  anynonarray_out	PGNSP PGUID 12 1 0 0 f f f t f i 1 0 2275 "2776" _null_ _null_ _null_ _null_ anynonarray_out _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3116 (  fdw_handler_in	PGNSP PGUID 12 1 0 0 f f f f f i 1 0 3115 "2275" _null_ _null_ _null_ _null_ fdw_handler_in _null_ _null_ _null_ ));
+DESCR("I/O");
+DATA(insert OID = 3117 (  fdw_handler_out	PGNSP PGUID 12 1 0 0 f f f t f i 1 0 2275 "3115" _null_ _null_ _null_ _null_ fdw_handler_out _null_ _null_ _null_ ));
+DESCR("I/O");
 
 /* cryptographic */
 DATA(insert OID =  2311 (  md5	   PGNSP PGUID 12 1 0 0 f f f t f i 1 0 25 "25" _null_ _null_ _null_ _null_ md5_text _null_ _null_ _null_ ));
diff --git a/src/include/catalog/pg_type.h b/src/include/catalog/pg_type.h
index d82078ec0ba..0f7312e495d 100644
--- a/src/include/catalog/pg_type.h
+++ b/src/include/catalog/pg_type.h
@@ -631,6 +631,8 @@ DATA(insert OID = 2776 ( anynonarray	PGNSP PGUID  4 t p P f t \054 0 0 0 anynona
 #define ANYNONARRAYOID	2776
 DATA(insert OID = 3500 ( anyenum		PGNSP PGUID  4 t p P f t \054 0 0 0 anyenum_in anyenum_out - - - - - i p f 0 -1 0 0 _null_ _null_ ));
 #define ANYENUMOID		3500
+DATA(insert OID = 3115 ( fdw_handler	PGNSP PGUID  4 t p P f t \054 0 0 0 fdw_handler_in fdw_handler_out - - - - - i p f 0 -1 0 0 _null_ _null_ ));
+#define FDW_HANDLEROID		3115
 
 
 /*
diff --git a/src/include/foreign/foreign.h b/src/include/foreign/foreign.h
index 2d1495cfe13..2cf0eaa09cc 100644
--- a/src/include/foreign/foreign.h
+++ b/src/include/foreign/foreign.h
@@ -37,7 +37,8 @@ typedef struct ForeignDataWrapper
 	Oid			fdwid;			/* FDW Oid */
 	Oid			owner;			/* FDW owner user Oid */
 	char	   *fdwname;		/* Name of the FDW */
-	Oid			fdwvalidator;
+	Oid			fdwhandler;		/* Oid of handler function, or 0 */
+	Oid			fdwvalidator;	/* Oid of validator function, or 0 */
 	List	   *options;		/* fdwoptions as DefElem list */
 } ForeignDataWrapper;
 
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 8aaa8c1d2f7..63a61e3da24 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -1574,7 +1574,7 @@ typedef struct CreateFdwStmt
 {
 	NodeTag		type;
 	char	   *fdwname;		/* foreign-data wrapper name */
-	List	   *validator;		/* optional validator function (qual. name) */
+	List	   *func_options;	/* HANDLER/VALIDATOR options */
 	List	   *options;		/* generic options to FDW */
 } CreateFdwStmt;
 
@@ -1582,8 +1582,7 @@ typedef struct AlterFdwStmt
 {
 	NodeTag		type;
 	char	   *fdwname;		/* foreign-data wrapper name */
-	List	   *validator;		/* optional validator function (qual. name) */
-	bool		change_validator;
+	List	   *func_options;	/* HANDLER/VALIDATOR options */
 	List	   *options;		/* generic options to FDW */
 } AlterFdwStmt;
 
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 277aec414c3..8392be6208a 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -508,6 +508,8 @@ extern Datum trigger_in(PG_FUNCTION_ARGS);
 extern Datum trigger_out(PG_FUNCTION_ARGS);
 extern Datum language_handler_in(PG_FUNCTION_ARGS);
 extern Datum language_handler_out(PG_FUNCTION_ARGS);
+extern Datum fdw_handler_in(PG_FUNCTION_ARGS);
+extern Datum fdw_handler_out(PG_FUNCTION_ARGS);
 extern Datum internal_in(PG_FUNCTION_ARGS);
 extern Datum internal_out(PG_FUNCTION_ARGS);
 extern Datum opaque_in(PG_FUNCTION_ARGS);