Use RTLD_NOW, not RTLD_LAZY, as binding mode for dlopen() on all platforms.

This restores the Linux behavior to what it was in PG 7.0 and 7.1, and
causes other platforms to agree.  (Other well-tested platforms like HPUX
were doing it this way already.)  Per pghackers discussion over the past
month or so.
This commit is contained in:
Tom Lane 2002-02-12 23:41:25 +00:00
parent baa0bb97b0
commit fa046b6a92
17 changed files with 266 additions and 79 deletions

View File

@ -39,8 +39,8 @@ table. If the path does not contain a '/' character, dlopen will search
for the module using the LIBPATH environment variable. It returns an
opaque handle to the module or NULL on error. The mode parameter can be
either RTLD_LAZY (for lazy function binding) or RTLD_NOW for immediate
function binding. The AIX implementation currently does treat RTLD_NOW
the same as RTLD_LAZY. The flag RTLD_GLOBAL might be or'ed into the
function binding. The AIX implementation currently behaves as RTLD_NOW
even if RTLD_LAZY is specified. The flag RTLD_GLOBAL might be or'ed into the
mode parameter to allow loaded modules to bind to global variables or
functions in other loaded modules loaded by dlopen(). If RTLD_GLOBAL is
not specified, only globals from the main part of the executable or

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@ -1,5 +1,5 @@
/*
* $Id: aix.h,v 1.10 2001/11/08 20:37:52 momjian Exp $
* $Id: aix.h,v 1.11 2002/02/12 23:39:46 tgl Exp $
*
* @(#)dlfcn.h 1.4 revision of 95/04/25 09:36:52
* This is an unpublished work copyright (c) 1992 HELIOS Software GmbH
@ -57,7 +57,7 @@ int dlclose();
#include "utils/dynamic_loader.h"
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
#define pg_dlopen(f) dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym dlsym
#define pg_dlclose dlclose
#define pg_dlerror dlerror

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@ -1,12 +1,12 @@
/*-------------------------------------------------------------------------
*
* Dynamic loader interface for BSD/OS
*
* bsdi.h
* Dynamic loader interface for BSD/OS
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* port_protos.h,v 1.2 1995/05/25 22:51:03 andrew Exp
* $Id: bsdi.h,v 1.15 2002/02/12 23:39:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -19,7 +19,21 @@
#ifdef HAVE_DLOPEN
#include <dlfcn.h>
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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
@ -32,6 +46,7 @@ do { \
dld_unlink_by_file(handle, 1); \
free(handle); \
} while (0)
#endif /* not HAVE_DLOPEN */
#endif /* PORT_PROTOS_H */

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@ -5,7 +5,7 @@
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: dgux.h,v 1.13 2001/11/05 17:46:27 momjian Exp $
* $Id: dgux.h,v 1.14 2002/02/12 23:40:03 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -21,9 +21,22 @@
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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

View File

@ -1,13 +1,12 @@
/*-------------------------------------------------------------------------
*
* port_protos.h
* port-specific prototypes for NetBSD 1.0
*
* freebsd.h
* port-specific prototypes for FreeBSD
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: freebsd.h,v 1.14 2002/02/11 21:38:11 petere Exp $
* $Id: freebsd.h,v 1.15 2002/02/12 23:40:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -21,7 +20,6 @@
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on NetBSD 1.0.
*
@ -35,11 +33,20 @@
* NetBSD (like 1.0, and 1.0A pre June 1995) have no dlerror.)
*/
/*
* 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) BSD44_derived_dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
#define pg_dlopen(f) BSD44_derived_dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym BSD44_derived_dlsym
#define pg_dlclose BSD44_derived_dlclose
#define pg_dlerror BSD44_derived_dlerror

View File

@ -1,13 +1,13 @@
/*-------------------------------------------------------------------------
*
* port_protos.h
* irix5.h
* port-specific prototypes for Irix 5
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* port_protos.h,v 1.2 1995/03/17 06:40:18 andrew Exp
* $Id: irix5.h,v 1.12 2002/02/12 23:40:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -17,16 +17,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on SunOS 4.
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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

View File

@ -1,12 +1,13 @@
/*-------------------------------------------------------------------------
*
* Dynamic loader interface for Linux
* linux.h
* Port-specific prototypes for Linux
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: linux.h,v 1.16 2001/11/05 17:46:27 momjian Exp $
* $Id: linux.h,v 1.17 2002/02/12 23:40:29 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -35,7 +36,20 @@ do { \
#else /* HAVE_DLOPEN */
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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

View File

@ -1,13 +1,13 @@
/*-------------------------------------------------------------------------
*
* port_protos.h
* port-specific prototypes for NetBSD 1.0
* netbsd.h
* port-specific prototypes for NetBSD
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: netbsd.h,v 1.8 2001/11/05 17:46:27 momjian Exp $
* $Id: netbsd.h,v 1.9 2002/02/12 23:40:37 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -21,7 +21,6 @@
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on NetBSD 1.0.
*
@ -34,7 +33,21 @@
* begin with an underscore is fairly tricky, and some versions of
* NetBSD (like 1.0, and 1.0A pre June 1995) have no dlerror.)
*/
#define pg_dlopen(f) BSD44_derived_dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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) BSD44_derived_dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym BSD44_derived_dlsym
#define pg_dlclose BSD44_derived_dlclose
#define pg_dlerror BSD44_derived_dlerror

View File

@ -1,11 +1,12 @@
/*-------------------------------------------------------------------------
*
* Dynamic loader for OpenBSD
* openbsd.h
* port-specific prototypes for OpenBSD
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: openbsd.h,v 1.9 2001/11/05 17:46:27 momjian Exp $
* $Id: openbsd.h,v 1.10 2002/02/12 23:40:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -19,7 +20,6 @@
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on NetBSD 1.0.
*
@ -32,7 +32,21 @@
* begin with an underscore is fairly tricky, and some versions of
* NetBSD (like 1.0, and 1.0A pre June 1995) have no dlerror.)
*/
#define pg_dlopen(f) BSD44_derived_dlopen((f), RTLD_LAZY)
/*
* 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) BSD44_derived_dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym BSD44_derived_dlsym
#define pg_dlclose BSD44_derived_dlclose
#define pg_dlerror BSD44_derived_dlerror

View File

@ -1,13 +1,13 @@
/*-------------------------------------------------------------------------
*
* alpha.h
* osf.h
* prototypes for OSF/1-specific routines
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: osf.h,v 1.7 2001/11/15 16:08:15 petere Exp $
* $Id: osf.h,v 1.8 2002/02/12 23:40:43 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -18,23 +18,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on Alpha OSF/1.x
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
/* RTLD_GLOBAL is not available in <5.x */
/*
* 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_LAZY | RTLD_GLOBAL)
#define pg_dlopen(f) dlopen((f), RTLD_NOW | RTLD_GLOBAL)
#define pg_dlsym(h, f) ((PGFunction) dlsym(h, f))
#define pg_dlclose(h) dlclose(h)
#define pg_dlerror() dlerror()

View File

@ -1,13 +1,13 @@
/*-------------------------------------------------------------------------
*
* port_protos.h
* sco.h
* port-specific prototypes for SCO 3.2v5.2
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: sco.h,v 1.11 2001/11/05 17:46:27 momjian Exp $
* $Id: sco.h,v 1.12 2002/02/12 23:40:47 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -17,20 +17,30 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on SCO 3.2v5.0.2
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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
/* port.c */
#endif /* PORT_PROTOS_H */

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@ -1,14 +1,38 @@
/* $Header: /cvsroot/pgsql/src/backend/port/dynloader/solaris.h,v 1.7 2001/11/05 17:46:27 momjian Exp $ */
#ifndef DYNLOADER_SOLARIS_H
#define DYNLOADER_SOLARIS_H
/*-------------------------------------------------------------------------
*
* solaris.h
* port-specific prototypes for Solaris
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: solaris.h,v 1.8 2002/02/12 23:40:53 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef PORT_PROTOS_H
#define PORT_PROTOS_H
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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 /* DYNLOADER_SOLARIS_H */
#endif /* PORT_PROTOS_H */

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@ -1,13 +1,13 @@
/*-------------------------------------------------------------------------
*
* port_protos.h
* sunos4.h
* port-specific prototypes for SunOS 4
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: sunos4.h,v 1.12 2001/12/05 02:03:59 ishii Exp $
* $Id: sunos4.h,v 1.13 2002/02/12 23:40:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -17,16 +17,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on SunOS 4.
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f),1)
/*
* 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

View File

@ -1,34 +1,46 @@
/*-------------------------------------------------------------------------
*
* dynloader.h
* svr4.h
* port-specific prototypes for Intel x86/Intel SVR4
*
*
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: svr4.h,v 1.11 2001/11/05 17:46:27 momjian Exp $
* $Id: svr4.h,v 1.12 2002/02/12 23:41:01 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef DYNLOADER_H
#define DYNLOADER_H
#ifndef PORT_PROTOS_H
#define PORT_PROTOS_H
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.h */
/*
* Dynamic Loader on Intel x86/Intel SVR4.
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
/*
* 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 /* DYNLOADER_H */
#endif /* PORT_PROTOS_H */

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@ -17,16 +17,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on Intel x86/Intel SVR4.
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
*/
/*
* 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

View File

@ -17,16 +17,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on Intel x86/Intel SVR4.
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
*/
/*
* 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

View File

@ -17,16 +17,28 @@
#include <dlfcn.h>
#include "utils/dynamic_loader.h"
/* dynloader.c */
/*
* Dynamic Loader on Intel x86/Windows NT
*
* this dynamic loader uses the system dynamic loading interface for shared
* libraries (ie. dlopen/dlsym/dlclose). The user must specify a shared
* library as the file to be dynamically loaded.
*
*/
#define pg_dlopen(f) dlopen((f), RTLD_LAZY | RTLD_GLOBAL)
*/
/*
* 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