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/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* This file must be included first by every library source file.
*/
#ifndef _DM_LIB_H
#define _DM_LIB_H
/*
* Symbol export control macros
*
* DM_EXPORT_NEW_SYMBOL(rettype, func, ver)
* DM_EXPORT_SYMBOL(func,ver)
* DM_EXPORT_SYMBOL_BASE(func,ver)
*
* For functions that have multiple implementations these macros control
* symbol export and versioning.
*
* Function definitions that exist in only one version never need to use
* these macros.
*
* Backwards compatible implementations must include a version tag of
* the form "_v1_02_104" as a suffix to the function name and use the
* macro DM_EXPORT_SYMBOL to export the function and bind it to the
* specified version string.
*
* Since versioning is only available when compiling with GCC the entire
* compatibility version should be enclosed in '#if defined(GNU_SYMVER)',
* for example:
*
* DM_EXPORT_NEW_SYMBOL(int, dm_foo, 1_02_107)(int bar)
* {
* return bar;
* }
*
* #if defined(GNU_SYMVER)
* // Backward compatible dm_foo() version 1.02.104
* DM_EXPORT_SYMBOL(dm_foo,1_02_104)
* int dm_foo_v1_02_104(void);
* int dm_foo_v1_02_104(void)
* {
* return 0;
* }
* #endif
*
* A prototype for the compatibility version is required as these
* functions must not be declared static.
*
* The DM_EXPORT_SYMBOL_BASE macro is only used to export the base
* versions of library symbols prior to the introduction of symbol
* versioning: it must never be used for new symbols.
*/
#if defined(GNU_SYMVER)
# ifdef __has_attribute
# if __has_attribute(symver)
# define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) \
__attribute__((__symver__( #func "@@DM_" #ver ))) \
__typeof__(func) func ##_v ##ver; \
rettype func ##_v ##ver
# define DM_EXPORT_SYMBOL(func, ver) \
__attribute__((__symver__( #func "@DM_" #ver )))
# define DM_EXPORT_SYMBOL_BASE(func) \
__attribute__((__symver__( #func "@Base" )))
# endif
# endif
#ifndef DM_EXPORT_NEW_SYMBOL
#define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) \
__typeof__(func) func ##_v ##ver; \
__asm__(".symver " #func "_v" #ver ", " #func "@@DM_" #ver ); \
rettype func ##_v ##ver
#define DM_EXPORT_SYMBOL(func, ver) \
__asm__(".symver " #func "_v" #ver ", " #func "@DM_" #ver );
#define DM_EXPORT_SYMBOL_BASE(func) \
__asm__(".symver " #func "_base, " #func "@Base" );
#endif
#else
#define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) rettype func
#define DM_EXPORT_SYMBOL(func, ver)
#define DM_EXPORT_SYMBOL_BASE(func)
#endif
#include "libdm/dm-tools/util.h"
#include "libdm/libdevmapper.h"
#include "libdm/misc/dm-logging.h"
#include <unistd.h>
#endif
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