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>

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>

Our linux distribution at my job didn't include a /tmp directory. When ever
I tried to use syslinux, I would get the following error:

./syslinux: No such file or directory

I modified the code to report this:

./syslinux: Cannot access the /tmp/ directory.

This would have helped me a lot rather than having to download the source
and run it through the debugger to figure out that my /tmp/ directory was
missing. I suspect if this ever happens again I'll know exactly what was
wrong, but hopefully it will help someone else.

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>

Fix mishandling of the null pathname case in the syslinux installer,
and generally clean up the handling of the subpath name.

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

Put all the Linux ioctl header magic into a single shared file, and
try to make it as generally useful as possible.

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

Switch to consistent use of 64-bit sector pointers; this should enable
booting even for individual *partitions* larger than 2 TB.  In order
to not slow down the boot too much, switch the initial load from an
enumeration to an extent map.  This means the table gets larger (since
we have to assume the worst case), but it simplifies the Sector 1 code
(since we can push all the hard stuff into the installer), and will
speed up booting in the general case.

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

When installing into the root directory, we should logically search
the root directory first.  Thus, we need to make sure the current path
is "/" not "".

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

Provide for backwards command-line compatibility, together with
warning messages where appropriate.

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

-o has been supported for a very long time; recommend using -t
instead, but for now proceed with an error message.

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