mk_elfconfig.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <elf.h>
int
main(int argc, char **argv)
{
unsigned char ei[EI_NIDENT];
union { short s; char c[2]; } endian_test;
if (fread(ei, 1, EI_NIDENT, stdin) != EI_NIDENT) {
fprintf(stderr, "Error: input truncated\n");
return 1;
}
if (memcmp(ei, ELFMAG, SELFMAG) != 0) {
fprintf(stderr, "Error: not ELF\n");
return 1;
}
switch (ei[EI_CLASS]) {
case ELFCLASS32:
printf("#define KERNEL_ELFCLASS ELFCLASS32\n");
break;
case ELFCLASS64:
printf("#define KERNEL_ELFCLASS ELFCLASS64\n");
break;
default:
exit(1);
}
switch (ei[EI_DATA]) {
case ELFDATA2LSB:
printf("#define KERNEL_ELFDATA ELFDATA2LSB\n");
break;
case ELFDATA2MSB:
printf("#define KERNEL_ELFDATA ELFDATA2MSB\n");
break;
default:
exit(1);
}
if (sizeof(unsigned long) == 4) {
printf("#define HOST_ELFCLASS ELFCLASS32\n");
} else if (sizeof(unsigned long) == 8) {
printf("#define HOST_ELFCLASS ELFCLASS64\n");
}
endian_test.s = 0x0102;
if (memcmp(endian_test.c, "\x01\x02", 2) == 0)
printf("#define HOST_ELFDATA ELFDATA2MSB\n");
else if (memcmp(endian_test.c, "\x02\x01", 2) == 0)
printf("#define HOST_ELFDATA ELFDATA2LSB\n");
else
exit(1);
return 0;
}