1 /* Generic relocation support for BFD. 2 Copyright (C) 1998-2020 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software Foundation, 18 Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 /* These macros are used by the various *.h target specific header 21 files to either generate an enum containing all the known relocations 22 for that target, or if RELOC_MACROS_GEN_FUNC is defined, a recognition 23 function is generated instead. (This is used by binutils/readelf.c) 24 25 Given a header file like this: 26 27 START_RELOC_NUMBERS (foo) 28 RELOC_NUMBER (R_foo_NONE, 0) 29 RELOC_NUMBER (R_foo_32, 1) 30 EMPTY_RELOC (R_foo_good) 31 FAKE_RELOC (R_foo_illegal, 9) 32 END_RELOC_NUMBERS (R_foo_count) 33 34 Then the following will be produced by default (ie if 35 RELOC_MACROS_GEN_FUNC is *not* defined). 36 37 enum foo 38 { 39 R_foo_NONE = 0, 40 R_foo_32 = 1, 41 R_foo_good, 42 R_foo_illegal = 9, 43 R_foo_count 44 }; 45 46 Note: The value of the symbol defined in the END_RELOC_NUMBERS 47 macro (R_foo_count in the case of the example above) will be 48 set to the value of the whichever *_RELOC macro precedes it plus 49 one. Therefore if you intend to use the symbol as a sentinel for 50 the highest valid macro value you should make sure that the 51 preceding *_RELOC macro is the highest valid number. ie a 52 declaration like this: 53 54 START_RELOC_NUMBERS (foo) 55 RELOC_NUMBER (R_foo_NONE, 0) 56 RELOC_NUMBER (R_foo_32, 1) 57 FAKE_RELOC (R_foo_illegal, 9) 58 FAKE_RELOC (R_foo_synonym, 0) 59 END_RELOC_NUMBERS (R_foo_count) 60 61 will result in R_foo_count having a value of 1 (R_foo_synonym + 1) 62 rather than 10 or 2 as might be expected. 63 64 Alternatively you can assign a value to END_RELOC_NUMBERS symbol 65 explicitly, like this: 66 67 START_RELOC_NUMBERS (foo) 68 RELOC_NUMBER (R_foo_NONE, 0) 69 RELOC_NUMBER (R_foo_32, 1) 70 FAKE_RELOC (R_foo_illegal, 9) 71 FAKE_RELOC (R_foo_synonym, 0) 72 END_RELOC_NUMBERS (R_foo_count = 2) 73 74 If RELOC_MACROS_GEN_FUNC *is* defined, then instead the 75 following function will be generated: 76 77 static const char *foo (unsigned long rtype); 78 static const char * 79 foo (unsigned long rtype) 80 { 81 switch (rtype) 82 { 83 case 0: return "R_foo_NONE"; 84 case 1: return "R_foo_32"; 85 default: return NULL; 86 } 87 } 88 */ 89 90 #ifndef _RELOC_MACROS_H 91 #define _RELOC_MACROS_H 92 93 #ifdef RELOC_MACROS_GEN_FUNC 94 95 /* This function takes the relocation number and returns the 96 string version name of the name of that relocation. If 97 the relocation is not recognised, NULL is returned. */ 98 99 #define START_RELOC_NUMBERS(name) \ 100 static const char *name (unsigned long rtype); \ 101 static const char * \ 102 name (unsigned long rtype) \ 103 { \ 104 switch (rtype) \ 105 { 106 107 #define RELOC_NUMBER(name, number) \ 108 case number: return #name; 109 110 #define FAKE_RELOC(name, number) 111 #define EMPTY_RELOC(name) 112 113 #define END_RELOC_NUMBERS(name) \ 114 default: return NULL; \ 115 } \ 116 } 117 118 119 #else /* Default to generating enum. */ 120 121 #define START_RELOC_NUMBERS(name) enum name { 122 #define RELOC_NUMBER(name, number) name = number, 123 #define FAKE_RELOC(name, number) name = number, 124 #define EMPTY_RELOC(name) name, 125 #define END_RELOC_NUMBERS(name) name }; 126 127 #endif 128 129 #endif /* _RELOC_MACROS_H */ 130