#!/bin/sh
  
  SYSROOT="${1}"
  # Make sure we have enough version components
  HDR_VER="${2}.0.0"
  
  HDR_M="${HDR_VER%%.*}"
  HDR_V="${HDR_VER#*.}"
  HDR_m="${HDR_V%%.*}"
  
  EXEC="$(mktemp -t check-headers.XXXXXX)"
  
  # We do not want to account for the patch-level, since headers are
  # not supposed to change for different patchlevels, so we mask it out.
  # This only applies to kernels >= 3.0, but those are the only one
  # we actually care about; we treat all 2.6.x kernels equally.
  ${HOSTCC} -imacros "${SYSROOT}/usr/include/linux/version.h" \
            -x c -o "${EXEC}" - <<_EOF_
  #include <stdio.h>
  #include <stdlib.h>
  
  int main(int argc __attribute__((unused)),
           char** argv __attribute__((unused)))
  {
      if((LINUX_VERSION_CODE & ~0xFF)
          != KERNEL_VERSION(${HDR_M},${HDR_m},0))
      {
          printf("Incorrect selection of kernel headers: ");
          printf("expected %d.%d.x, got %d.%d.x
  ", ${HDR_M}, ${HDR_m},
                 ((LINUX_VERSION_CODE>>16) & 0xFF),
                 ((LINUX_VERSION_CODE>>8) & 0xFF));
          return 1;
      }
      return 0;
  }
  _EOF_
  
  "${EXEC}"
  ret=${?}
  rm -f "${EXEC}"
  exit ${ret}