foreign.h

Go to the documentation of this file.

/*-------------------------------------------------------------------------
 *
 * foreign.h
 *    support for foreign-data wrappers, servers and user mappings.
 *
 *
 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
 *
 * src/include/foreign/foreign.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef FOREIGN_H
#define FOREIGN_H

#include "nodes/parsenodes.h"


/* Helper for obtaining username for user mapping */
#define MappingUserName(userid) \
    (OidIsValid(userid) ? GetUserNameFromId(userid) : "public")


/*
 * Generic option types for validation.
 * NB! Thes are treated as flags, so use only powers of two here.
 */
typedef enum
{
    ServerOpt = 1,              /* options applicable to SERVER */
    UserMappingOpt = 2,         /* options for USER MAPPING */
    FdwOpt = 4                  /* options for FOREIGN DATA WRAPPER */
} GenericOptionFlags;

typedef struct ForeignDataWrapper
{
    Oid         fdwid;          /* FDW Oid */
    Oid         owner;          /* FDW owner user Oid */
    char       *fdwname;        /* Name of the FDW */
    Oid         fdwhandler;     /* Oid of handler function, or 0 */
    Oid         fdwvalidator;   /* Oid of validator function, or 0 */
    List       *options;        /* fdwoptions as DefElem list */
} ForeignDataWrapper;

typedef struct ForeignServer
{
    Oid         serverid;       /* server Oid */
    Oid         fdwid;          /* foreign-data wrapper */
    Oid         owner;          /* server owner user Oid */
    char       *servername;     /* name of the server */
    char       *servertype;     /* server type, optional */
    char       *serverversion;  /* server version, optional */
    List       *options;        /* srvoptions as DefElem list */
} ForeignServer;

typedef struct UserMapping
{
    Oid         userid;         /* local user Oid */
    Oid         serverid;       /* server Oid */
    List       *options;        /* useoptions as DefElem list */
} UserMapping;

typedef struct ForeignTable
{
    Oid         relid;          /* relation Oid */
    Oid         serverid;       /* server Oid */
    List       *options;        /* ftoptions as DefElem list */
} ForeignTable;


extern ForeignServer *GetForeignServer(Oid serverid);
extern ForeignServer *GetForeignServerByName(const char *name, bool missing_ok);
extern UserMapping *GetUserMapping(Oid userid, Oid serverid);
extern ForeignDataWrapper *GetForeignDataWrapper(Oid fdwid);
extern ForeignDataWrapper *GetForeignDataWrapperByName(const char *name,
                            bool missing_ok);
extern ForeignTable *GetForeignTable(Oid relid);

extern List *GetForeignColumnOptions(Oid relid, AttrNumber attnum);

extern Oid  get_foreign_data_wrapper_oid(const char *fdwname, bool missing_ok);
extern Oid  get_foreign_server_oid(const char *servername, bool missing_ok);

#endif   /* FOREIGN_H */