postgresql/src/backend/port/dynloader/linux.h

/*-------------------------------------------------------------------------
 *
 * linux.h
 *		Port-specific prototypes for Linux
 *
 *
 * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * $Id: linux.h,v 1.18 2002/06/20 20:29:33 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#ifndef PORT_PROTOS_H
#define PORT_PROTOS_H

#include "utils/dynamic_loader.h"
#ifdef HAVE_DLOPEN
#include <dlfcn.h>
#endif


#ifndef HAVE_DLOPEN

#ifndef HAVE_DLD_H
#define pg_dlsym(handle, funcname)		(NULL)
#define pg_dlclose(handle)			   {}
#else
#define pg_dlsym(handle, funcname)		((PGFunction) dld_get_func((funcname)))
#define pg_dlclose(handle) \
do { \
	dld_unlink_by_file(handle, 1); \
	free(handle); \
} while (0)
#endif

#else							/* HAVE_DLOPEN */

/*
 * In some older systems, the RTLD_NOW flag isn't defined and the mode
 * argument to dlopen must always be 1.  The RTLD_GLOBAL flag is wanted
 * if available, but it doesn't exist everywhere.
 * If it doesn't exist, set it to 0 so it has no effect.
 */
#ifndef RTLD_NOW
#define RTLD_NOW 1
#endif
#ifndef RTLD_GLOBAL
#define RTLD_GLOBAL 0
#endif

#define pg_dlopen(f)	dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym		dlsym
#define pg_dlclose		dlclose
#define pg_dlerror		dlerror
#endif   /* HAVE_DLOPEN */

#endif   /* PORT_PROTOS_H */