/* * Copyright (c) 2006-2008 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ * * * Copyright (c) 1999 John D. Polstra * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #ifndef _SYS_LINKER_SET_H_ #define _SYS_LINKER_SET_H_ #include #if !defined(KERNEL) || defined(__APPLE_API_PRIVATE) /* * The following macros are used to declare global sets of objects, which * are collected by the linker into a `linker set' as defined below. * For Mach-O, this is done by constructing a separate segment inside the * __DATA section for each set. The contents of this segment are an array * of pointers to the objects in the set. * * Note that due to limitations of the Mach-O format, there cannot * be more than 255 sections in a segment, so linker set usage should be * conserved. Set names may not exceed 16 characters. */ #ifdef KERNEL # include # include #else # include # include # include #endif /* * Private macros, not to be used outside this header file. * * The objective of this macro stack is to produce the following output, * given SET and SYM as arguments: * * void const * __set_SET_sym_SYM __attribute__((section("__DATA,SET"))) = & SYM */ #ifdef __LS_VA_STRINGIFY__ # undef __LS_VA_STRINGIFY__ #endif #ifdef __LS_VA_STRCONCAT__ # undef __LS_VA_STRCONCAT__ #endif #define __LS_VA_STRINGIFY(_x...) #_x #define __LS_VA_STRCONCAT(_x,_y) __LS_VA_STRINGIFY(_x,_y) #define __LINKER_MAKE_SET(_set, _sym) \ /*__unused*/ /*static*/ void const * /*const*/ __set_##_set##_sym_##_sym \ __attribute__ ((section(__LS_VA_STRCONCAT(__DATA,_set)),used)) = (void *)&_sym /* the line above is very fragile - if your compiler breaks linker sets, just play around with "static", "const", "used" etc. :-) */ /* * Public macros. */ #define LINKER_SET_ENTRY(_set, _sym) __LINKER_MAKE_SET(_set, _sym) /* * FreeBSD compatibility. */ #ifdef __APPLE_API_OBSOLETE # define TEXT_SET(_set, _sym) __LINKER_MAKE_SET(_set, _sym) # define DATA_SET(_set, _sym) __LINKER_MAKE_SET(_set, _sym) # define BSS_SET(_set, _sym) __LINKER_MAKE_SET(_set, _sym) # define ABS_SET(_set, _sym) __LINKER_MAKE_SET(_set, _sym) # define SET_ENTRY(_set, _sym) __LINKER_MAKE_SET(_set, _sym) #endif /* __APPLE_API_OBSOLETE */ /* * Extended linker set API. * * Since linker sets are per-object-file, and we may have multiple * object files, we need to be able to specify which object's set * to scan. * * The set itself is a contiguous array of pointers to the objects * within the set. */ /* * Public interface. * * void **LINKER_SET_OBJECT_BEGIN(_object, _set) * Preferred interface to linker_set_object_begin(), takes set name unquoted. * void **LINKER_SET_OBJECT_LIMIT(_object, _set) * Preferred interface to linker_set_object_begin(), takes set name unquoted. * LINKER_SET_OBJECT_FOREACH(_object, (set_member_type **)_pvar, _cast, _set) * Iterates over the members of _set within _object. Since the set contains * pointers to its elements, for a set of elements of type etyp, _pvar must * be (etyp **). * set_member_type **LINKER_SET_OBJECT_ITEM(_object, _set, _i) * Returns a pointer to the _i'th element of _set within _object. * * void **LINKER_SET_BEGIN(_set) * void **LINKER_SET_LIMINT(_set) * LINKER_SET_FOREACH((set_member_type **)_pvar, _cast, _set) * set_member_type **LINKER_SET_ITEM(_set, _i) * These versions implicitly reference the kernel/application object. * * Example of _cast: For the _pvar "struct sysctl_oid **oidpp", _cast would be * "struct sysctl_oid **" * */ #define LINKER_SET_OBJECT_BEGIN(_object, _set) __linker_set_object_begin(_object, _set) #define LINKER_SET_OBJECT_LIMIT(_object, _set) __linker_set_object_limit(_object, _set) #define LINKER_SET_OBJECT_FOREACH(_object, _pvar, _cast, _set) \ for (_pvar = (_cast) LINKER_SET_OBJECT_BEGIN(_object, _set); \ _pvar < (_cast) LINKER_SET_OBJECT_LIMIT(_object, _set); \ _pvar++) #define LINKER_SET_OBJECT_ITEM(_object, _set, _i) \ ((LINKER_SET_OBJECT_BEGIN(_object, _set))[_i]) #define LINKER_SET_BEGIN(_set) \ LINKER_SET_OBJECT_BEGIN((kernel_mach_header_t *)&_mh_execute_header, _set) #define LINKER_SET_LIMIT(_set) \ LINKER_SET_OBJECT_LIMIT((kernel_mach_header_t *)&_mh_execute_header, _set) #define LINKER_SET_FOREACH(_pvar, _cast, _set) \ LINKER_SET_OBJECT_FOREACH((kernel_mach_header_t *)&_mh_execute_header, _pvar, _cast, _set) #define LINKER_SET_ITEM(_set, _i) \ LINKER_SET_OBJECT_ITEM((kernel_mach_header_t *)&_mh_execute_header, _set, _i) /* * Implementation. * * void **__linker_set_object_begin(_header, _set) * Returns a pointer to the first pointer in the linker set. * void **__linker_set_object_limi(_header, _set) * Returns an upper bound to the linker set (base + size). */ static __inline void ** __linker_set_object_begin(kernel_mach_header_t *_header, const char *_set) __attribute__((__const__)); static __inline void ** __linker_set_object_begin(kernel_mach_header_t *_header, const char *_set) { void *_set_begin; unsigned long _size; _set_begin = getsectdatafromheader(_header, "__DATA", _set, &_size); return( (void **) _set_begin ); } static __inline void ** __linker_set_object_limit(kernel_mach_header_t *_header, const char *_set) __attribute__((__const__)); static __inline void ** __linker_set_object_limit(kernel_mach_header_t *_header, const char *_set) { void *_set_begin; unsigned long _size; _set_begin = getsectdatafromheader(_header, "__DATA", _set, &_size); return ((void **) ((uintptr_t) _set_begin + _size)); } #endif /* !KERNEL || __APPLE_API_PRIVATE */ #endif /* _SYS_LINKER_SET_H_ */