RHEL4 had a 2.6.9 kernel, but 2.4.20 Linux kernel headers, so put in a
workaround for 2.4 kernel headers.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Some versions of glibc have broken versions of <linux/loop.h>, so
include our own canned version.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

If we are on a loop device, set bsHidden based on the loopback device
offset.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Make it possible to distinguish ENOENT from other "non-fatal" errors
in read_adv(), so we can try more than one filename.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

modify_adv() should be used by any installer which uses the common
CLI, so it should go into syslxopt.c.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

This file does not need <sys/types.h>.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Install an empty ADV in the Windows installer to keep it from being
broken.  In order to do that, separate the Unix-specific ADV I/O
functions from the generic data structure manipulation.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Merge the SYSLINUX and EXTLINUX patching code and core code, removing
EXTLINUX as a separate derivative.  All the disk-based systems now use
the same code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Reduce sector 1 space pressure by moving objects that aren't needed by
Sector 1 proper into an "extended patch area".  While we're mucking
with the installer code, make the syslxint and extlinux installer code
even more similar.  It should now be pretty straightforward to
outright merge the code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>