1// SPDX-License-Identifier: GPL-2.0
2#include <stdio.h>
3#include <stdlib.h>
4#include <string.h>
5#include <elf.h>
6
7int
8main(int argc, char **argv)
9{
10 unsigned char ei[EI_NIDENT];
11 union { short s; char c[2]; } endian_test;
12
13 if (fread(ptr: ei, size: 1, EI_NIDENT, stdin) != EI_NIDENT) {
14 fprintf(stderr, format: "Error: input truncated\n");
15 return 1;
16 }
17 if (memcmp(s1: ei, ELFMAG, SELFMAG) != 0) {
18 fprintf(stderr, format: "Error: not ELF\n");
19 return 1;
20 }
21 switch (ei[EI_CLASS]) {
22 case ELFCLASS32:
23 printf(format: "#define KERNEL_ELFCLASS ELFCLASS32\n");
24 break;
25 case ELFCLASS64:
26 printf(format: "#define KERNEL_ELFCLASS ELFCLASS64\n");
27 break;
28 default:
29 exit(status: 1);
30 }
31 switch (ei[EI_DATA]) {
32 case ELFDATA2LSB:
33 printf(format: "#define KERNEL_ELFDATA ELFDATA2LSB\n");
34 break;
35 case ELFDATA2MSB:
36 printf(format: "#define KERNEL_ELFDATA ELFDATA2MSB\n");
37 break;
38 default:
39 exit(status: 1);
40 }
41
42 if (sizeof(unsigned long) == 4) {
43 printf(format: "#define HOST_ELFCLASS ELFCLASS32\n");
44 } else if (sizeof(unsigned long) == 8) {
45 printf(format: "#define HOST_ELFCLASS ELFCLASS64\n");
46 }
47
48 endian_test.s = 0x0102;
49 if (memcmp(s1: endian_test.c, s2: "\x01\x02", n: 2) == 0)
50 printf(format: "#define HOST_ELFDATA ELFDATA2MSB\n");
51 else if (memcmp(s1: endian_test.c, s2: "\x02\x01", n: 2) == 0)
52 printf(format: "#define HOST_ELFDATA ELFDATA2LSB\n");
53 else
54 exit(status: 1);
55
56 return 0;
57}
58

source code of linux/scripts/mod/mk_elfconfig.c