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Editing: ldap_cdefs.h
/* $OpenLDAP$ */ /* This work is part of OpenLDAP Software <http://www.openldap.org/>. * * Copyright 1998-2018 The OpenLDAP Foundation. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted only as authorized by the OpenLDAP * Public License. * * A copy of this license is available in file LICENSE in the * top-level directory of the distribution or, alternatively, at * <http://www.OpenLDAP.org/license.html>. */ /* LDAP C Defines */ #ifndef _LDAP_CDEFS_H #define _LDAP_CDEFS_H #if defined(__cplusplus) || defined(c_plusplus) # define LDAP_BEGIN_DECL extern "C" { # define LDAP_END_DECL } #else # define LDAP_BEGIN_DECL /* begin declarations */ # define LDAP_END_DECL /* end declarations */ #endif #if !defined(LDAP_NO_PROTOTYPES) && ( defined(LDAP_NEEDS_PROTOTYPES) || \ defined(__STDC__) || defined(__cplusplus) || defined(c_plusplus) ) /* ANSI C or C++ */ # define LDAP_P(protos) protos # define LDAP_CONCAT1(x,y) x ## y # define LDAP_CONCAT(x,y) LDAP_CONCAT1(x,y) # define LDAP_STRING(x) #x /* stringify without expanding x */ # define LDAP_XSTRING(x) LDAP_STRING(x) /* expand x, then stringify */ #ifndef LDAP_CONST # define LDAP_CONST const #endif #else /* no prototypes */ /* traditional C */ # define LDAP_P(protos) () # define LDAP_CONCAT(x,y) x/**/y # define LDAP_STRING(x) "x" #ifndef LDAP_CONST # define LDAP_CONST /* no const */ #endif #endif /* no prototypes */ #if (__GNUC__) * 1000 + (__GNUC_MINOR__) >= 2006 # define LDAP_GCCATTR(attrs) __attribute__(attrs) #else # define LDAP_GCCATTR(attrs) #endif /* * Support for Windows DLLs. * * When external source code includes header files for dynamic libraries, * the external source code is "importing" DLL symbols into its resulting * object code. On Windows, symbols imported from DLLs must be explicitly * indicated in header files with the __declspec(dllimport) directive. * This is not totally necessary for functions because the compiler * (gcc or MSVC) will generate stubs when this directive is absent. * However, this is required for imported variables. * * The LDAP libraries, i.e. liblber and libldap, can be built as * static or shared, based on configuration. Just about all other source * code in OpenLDAP use these libraries. If the LDAP libraries * are configured as shared, 'configure' defines the LDAP_LIBS_DYNAMIC * macro. When other source files include LDAP library headers, the * LDAP library symbols will automatically be marked as imported. When * the actual LDAP libraries are being built, the symbols will not * be marked as imported because the LBER_LIBRARY or LDAP_LIBRARY macros * will be respectively defined. * * Any project outside of OpenLDAP with source code wanting to use * LDAP dynamic libraries should explicitly define LDAP_LIBS_DYNAMIC. * This will ensure that external source code appropriately marks symbols * that will be imported. * * The slapd executable, itself, can be used as a dynamic library. * For example, if a backend module is compiled as shared, it will * import symbols from slapd. When this happens, the slapd symbols * must be marked as imported in header files that the backend module * includes. Remember that slapd links with various static libraries. * If the LDAP libraries were configured as static, their object * code is also part of the monolithic slapd executable. Thus, when * a backend module imports symbols from slapd, it imports symbols from * all of the static libraries in slapd as well. Thus, the SLAP_IMPORT * macro, when defined, will appropriately mark symbols as imported. * This macro should be used by shared backend modules as well as any * other external source code that imports symbols from the slapd * executable as if it were a DLL. * * Note that we don't actually have to worry about using the * __declspec(dllexport) directive anywhere. This is because both * MSVC and Mingw provide alternate (more effective) methods for exporting * symbols out of binaries, i.e. the use of a DEF file. * * NOTE ABOUT BACKENDS: Backends can be configured as static or dynamic. * When a backend is configured as dynamic, slapd will load the backend * explicitly and populate function pointer structures by calling * the backend's well-known initialization function. Because of this * procedure, slapd never implicitly imports symbols from dynamic backends. * This makes it unnecessary to tag various backend functions with the * __declspec(dllimport) directive. This is because neither slapd nor * any other external binary should ever be implicitly loading a backend * dynamic module. * * Backends are supposed to be self-contained. However, it appears that * back-meta DOES implicitly import symbols from back-ldap. This means * that the __declspec(dllimport) directive should be marked on back-ldap * functions (in its header files) if and only if we're compiling for * windows AND back-ldap has been configured as dynamic AND back-meta * is the client of back-ldap. When client is slapd, there is no effect * since slapd does not implicitly import symbols. * * TODO(?): Currently, back-meta nor back-ldap is supported for Mingw32. * Thus, there's no need to worry about this right now. This is something that * may or may not have to be addressed in the future. */ /* LBER library */ #if defined(_WIN32) && \ ((defined(LDAP_LIBS_DYNAMIC) && !defined(LBER_LIBRARY)) || \ (!defined(LDAP_LIBS_DYNAMIC) && defined(SLAPD_IMPORT))) # define LBER_F(type) extern __declspec(dllimport) type # define LBER_V(type) extern __declspec(dllimport) type #else # define LBER_F(type) extern type # define LBER_V(type) extern type #endif /* LDAP library */ #if defined(_WIN32) && \ ((defined(LDAP_LIBS_DYNAMIC) && !defined(LDAP_LIBRARY)) || \ (!defined(LDAP_LIBS_DYNAMIC) && defined(SLAPD_IMPORT))) # define LDAP_F(type) extern __declspec(dllimport) type # define LDAP_V(type) extern __declspec(dllimport) type #else # define LDAP_F(type) extern type # define LDAP_V(type) extern type #endif /* AVL library */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_AVL_F(type) extern __declspec(dllimport) type # define LDAP_AVL_V(type) extern __declspec(dllimport) type #else # define LDAP_AVL_F(type) extern type # define LDAP_AVL_V(type) extern type #endif /* LDIF library */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_LDIF_F(type) extern __declspec(dllimport) type # define LDAP_LDIF_V(type) extern __declspec(dllimport) type #else # define LDAP_LDIF_F(type) extern type # define LDAP_LDIF_V(type) extern type #endif /* LUNICODE library */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_LUNICODE_F(type) extern __declspec(dllimport) type # define LDAP_LUNICODE_V(type) extern __declspec(dllimport) type #else # define LDAP_LUNICODE_F(type) extern type # define LDAP_LUNICODE_V(type) extern type #endif /* LUTIL library */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_LUTIL_F(type) extern __declspec(dllimport) type # define LDAP_LUTIL_V(type) extern __declspec(dllimport) type #else # define LDAP_LUTIL_F(type) extern type # define LDAP_LUTIL_V(type) extern type #endif /* REWRITE library */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_REWRITE_F(type) extern __declspec(dllimport) type # define LDAP_REWRITE_V(type) extern __declspec(dllimport) type #else # define LDAP_REWRITE_F(type) extern type # define LDAP_REWRITE_V(type) extern type #endif /* SLAPD (as a dynamic library exporting symbols) */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_SLAPD_F(type) extern __declspec(dllimport) type # define LDAP_SLAPD_V(type) extern __declspec(dllimport) type #else # define LDAP_SLAPD_F(type) extern type # define LDAP_SLAPD_V(type) extern type #endif /* SLAPD (as a dynamic library exporting symbols) */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define LDAP_SLAPI_F(type) extern __declspec(dllimport) type # define LDAP_SLAPI_V(type) extern __declspec(dllimport) type #else # define LDAP_SLAPI_F(type) extern type # define LDAP_SLAPI_V(type) extern type #endif /* SLAPD (as a dynamic library exporting symbols) */ #if defined(_WIN32) && defined(SLAPD_IMPORT) # define SLAPI_F(type) extern __declspec(dllimport) type # define SLAPI_V(type) extern __declspec(dllimport) type #else # define SLAPI_F(type) extern type # define SLAPI_V(type) extern type #endif /* * C library. Mingw32 links with the dynamic C run-time library by default, * so the explicit definition of CSTATIC will keep dllimport from * being defined, if desired. * * MSVC defines the _DLL macro when the compiler is invoked with /MD or /MDd, * which means the resulting object code will be linked with the dynamic * C run-time library. * * Technically, it shouldn't be necessary to redefine any functions that * the headers for the C library should already contain. Nevertheless, this * is here as a safe-guard. * * TODO: Determine if these macros ever get expanded for Windows. If not, * the declspec expansion can probably be removed. */ #if (defined(__MINGW32__) && !defined(CSTATIC)) || \ (defined(_MSC_VER) && defined(_DLL)) # define LDAP_LIBC_F(type) extern __declspec(dllimport) type # define LDAP_LIBC_V(type) extern __declspec(dllimport) type #else # define LDAP_LIBC_F(type) extern type # define LDAP_LIBC_V(type) extern type #endif #endif /* _LDAP_CDEFS_H */
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