ARM: 8445/1: fix vdsomunge not to depend on glibc specific byteswap.h

If the host toolchain is not glibc based then the arm kernel build
fails with

  HOSTCC  arch/arm/vdso/vdsomunge
  arch/arm/vdso/vdsomunge.c:48:22: fatal error: byteswap.h: No such file or directory

Observed: with omap2plus_defconfig and compile on Mac OS X with arm ELF
cross-compiler.

Reason: byteswap.h is a glibc only header.

Solution: replace by private byte-swapping macros (taken from
arch/mips/boot/elf2ecoff.c and kindly improved by Russell King)

Tested to compile on Mac OS X 10.9.5 host.

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
H. Nikolaus Schaller 2015-10-16 22:19:06 +01:00 committed by Russell King
parent 868e87ccda
commit 8a603f91cc
1 changed files with 13 additions and 4 deletions

View File

@ -45,7 +45,6 @@
* it does.
*/
#include <byteswap.h>
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
@ -59,6 +58,16 @@
#include <sys/types.h>
#include <unistd.h>
#define swab16(x) \
((((x) & 0x00ff) << 8) | \
(((x) & 0xff00) >> 8))
#define swab32(x) \
((((x) & 0x000000ff) << 24) | \
(((x) & 0x0000ff00) << 8) | \
(((x) & 0x00ff0000) >> 8) | \
(((x) & 0xff000000) << 24))
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define HOST_ORDER ELFDATA2LSB
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
@ -104,17 +113,17 @@ static void cleanup(void)
static Elf32_Word read_elf_word(Elf32_Word word, bool swap)
{
return swap ? bswap_32(word) : word;
return swap ? swab32(word) : word;
}
static Elf32_Half read_elf_half(Elf32_Half half, bool swap)
{
return swap ? bswap_16(half) : half;
return swap ? swab16(half) : half;
}
static void write_elf_word(Elf32_Word val, Elf32_Word *dst, bool swap)
{
*dst = swap ? bswap_32(val) : val;
*dst = swap ? swab32(val) : val;
}
int main(int argc, char **argv)