1 /*- 2 * Copyright (c) 1999 John D. Polstra 3 * Copyright (c) 1999,2001 Peter Wemm <peter@FreeBSD.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #ifndef _SYS_LINKER_SET_H_ 31 #define _SYS_LINKER_SET_H_ 32 33 #ifndef _SYS_CDEFS_H_ 34 #error this file needs sys/cdefs.h as a prerequisite 35 #endif 36 37 /* 38 * The following macros are used to declare global sets of objects, which 39 * are collected by the linker into a `linker_set' as defined below. 40 * For ELF, this is done by constructing a separate segment for each set. 41 */ 42 43 #if defined(__powerpc64__) 44 /* 45 * Move the symbol pointer from ".text" to ".data" segment, to make 46 * the GCC compiler happy: 47 */ 48 #define __MAKE_SET_CONST 49 #else 50 #define __MAKE_SET_CONST const 51 #endif 52 53 /* 54 * Private macros, not to be used outside this header file. 55 */ 56 #ifdef __GNUCLIKE___SECTION 57 #define __MAKE_SET(set, sym) \ 58 __WEAK(__CONCAT(__start_set_,set)); \ 59 __WEAK(__CONCAT(__stop_set_,set)); \ 60 static void const * __MAKE_SET_CONST \ 61 __set_##set##_sym_##sym __section("set_" #set) \ 62 __used = &(sym) 63 #else /* !__GNUCLIKE___SECTION */ 64 #ifndef lint 65 #error this file needs to be ported to your compiler 66 #endif /* lint */ 67 #define __MAKE_SET(set, sym) extern void const * const (__set_##set##_sym_##sym) 68 #endif /* __GNUCLIKE___SECTION */ 69 70 /* 71 * Public macros. 72 */ 73 #define TEXT_SET(set, sym) __MAKE_SET(set, sym) 74 #define DATA_SET(set, sym) __MAKE_SET(set, sym) 75 #define BSS_SET(set, sym) __MAKE_SET(set, sym) 76 #define ABS_SET(set, sym) __MAKE_SET(set, sym) 77 #define SET_ENTRY(set, sym) __MAKE_SET(set, sym) 78 79 /* 80 * Initialize before referring to a given linker set. 81 */ 82 #define SET_DECLARE(set, ptype) \ 83 extern ptype __weak_symbol *__CONCAT(__start_set_,set); \ 84 extern ptype __weak_symbol *__CONCAT(__stop_set_,set) 85 86 #define SET_BEGIN(set) \ 87 (&__CONCAT(__start_set_,set)) 88 #define SET_LIMIT(set) \ 89 (&__CONCAT(__stop_set_,set)) 90 91 /* 92 * Iterate over all the elements of a set. 93 * 94 * Sets always contain addresses of things, and "pvar" points to words 95 * containing those addresses. Thus is must be declared as "type **pvar", 96 * and the address of each set item is obtained inside the loop by "*pvar". 97 */ 98 #define SET_FOREACH(pvar, set) \ 99 for (pvar = SET_BEGIN(set); pvar < SET_LIMIT(set); pvar++) 100 101 #define SET_ITEM(set, i) \ 102 ((SET_BEGIN(set))[i]) 103 104 /* 105 * Provide a count of the items in a set. 106 */ 107 #define SET_COUNT(set) \ 108 (SET_LIMIT(set) - SET_BEGIN(set)) 109 110 #endif /* _SYS_LINKER_SET_H_ */ 111