1 /*-
2 * Copyright (c) 2006,2008 Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/types.h>
28
29 #include <libelf.h>
30
31 #include "_libelf.h"
32
33 ELFTC_VCSID("$Id: libelf_align.c 3174 2015-03-27 17:13:41Z emaste $");
34
35 struct align {
36 unsigned int a32;
37 unsigned int a64;
38 };
39
40 #ifdef __GNUC__
41 #define MALIGN(N) { \
42 .a32 = __alignof__(Elf32_##N), \
43 .a64 = __alignof__(Elf64_##N) \
44 }
45 #define MALIGN64(V) { \
46 .a32 = 0, \
47 .a64 = __alignof__(Elf64_##V) \
48 }
49 #define MALIGN_WORD() { \
50 .a32 = __alignof__(int32_t), \
51 .a64 = __alignof__(int64_t) \
52 }
53 #else
54 #error Need the __alignof__ builtin.
55 #endif
56 #define UNSUPPORTED() { \
57 .a32 = 0, \
58 .a64 = 0 \
59 }
60
61 static struct align malign[ELF_T_NUM] = {
62 [ELF_T_ADDR] = MALIGN(Addr),
63 [ELF_T_BYTE] = { .a32 = 1, .a64 = 1 },
64 [ELF_T_CAP] = MALIGN(Cap),
65 [ELF_T_DYN] = MALIGN(Dyn),
66 [ELF_T_EHDR] = MALIGN(Ehdr),
67 [ELF_T_HALF] = MALIGN(Half),
68 [ELF_T_LWORD] = MALIGN(Lword),
69 [ELF_T_MOVE] = MALIGN(Move),
70 [ELF_T_MOVEP] = UNSUPPORTED(),
71 [ELF_T_NOTE] = MALIGN(Nhdr),
72 [ELF_T_OFF] = MALIGN(Off),
73 [ELF_T_PHDR] = MALIGN(Phdr),
74 [ELF_T_REL] = MALIGN(Rel),
75 [ELF_T_RELA] = MALIGN(Rela),
76 [ELF_T_SHDR] = MALIGN(Shdr),
77 [ELF_T_SWORD] = MALIGN(Sword),
78 [ELF_T_SXWORD] = MALIGN64(Sxword),
79 [ELF_T_SYM] = MALIGN(Sym),
80 [ELF_T_SYMINFO] = MALIGN(Syminfo),
81 [ELF_T_VDEF] = MALIGN(Verdef),
82 [ELF_T_VNEED] = MALIGN(Verneed),
83 [ELF_T_WORD] = MALIGN(Word),
84 [ELF_T_XWORD] = MALIGN64(Xword),
85 [ELF_T_GNUHASH] = MALIGN_WORD()
86 };
87
88 unsigned int
_libelf_malign(Elf_Type t,int elfclass)89 _libelf_malign(Elf_Type t, int elfclass)
90 {
91 if (t >= ELF_T_NUM || (int) t < 0)
92 return (0);
93
94 return (elfclass == ELFCLASS32 ? malign[t].a32 :
95 malign[t].a64);
96 }
97
98 #define FALIGN(A32,A64) { .a32 = (A32), .a64 = (A64) }
99
100 static struct align falign[ELF_T_NUM] = {
101 [ELF_T_ADDR] = FALIGN(4,8),
102 [ELF_T_BYTE] = FALIGN(1,1),
103 [ELF_T_CAP] = FALIGN(4,8),
104 [ELF_T_DYN] = FALIGN(4,8),
105 [ELF_T_EHDR] = FALIGN(4,8),
106 [ELF_T_HALF] = FALIGN(2,2),
107 [ELF_T_LWORD] = FALIGN(8,8),
108 [ELF_T_MOVE] = FALIGN(8,8),
109 [ELF_T_MOVEP] = UNSUPPORTED(),
110 [ELF_T_NOTE] = FALIGN(4,4),
111 [ELF_T_OFF] = FALIGN(4,8),
112 [ELF_T_PHDR] = FALIGN(4,8),
113 [ELF_T_REL] = FALIGN(4,8),
114 [ELF_T_RELA] = FALIGN(4,8),
115 [ELF_T_SHDR] = FALIGN(4,8),
116 [ELF_T_SWORD] = FALIGN(4,4),
117 [ELF_T_SXWORD] = FALIGN(0,8),
118 [ELF_T_SYM] = FALIGN(4,8),
119 [ELF_T_SYMINFO] = FALIGN(2,2),
120 [ELF_T_VDEF] = FALIGN(4,4),
121 [ELF_T_VNEED] = FALIGN(4,4),
122 [ELF_T_WORD] = FALIGN(4,4),
123 [ELF_T_XWORD] = FALIGN(0,8),
124 [ELF_T_GNUHASH] = FALIGN(4,8)
125 };
126
127 unsigned int
_libelf_falign(Elf_Type t,int elfclass)128 _libelf_falign(Elf_Type t, int elfclass)
129 {
130 if (t >= ELF_T_NUM || (int) t < 0)
131 return (0);
132
133 return (elfclass == ELFCLASS32 ? falign[t].a32 :
134 falign[t].a64);
135 }
136