[syslinux] Undef symbol FAIL: luaL_checklstring in vesa.c32

[Ady]

> "H. Peter Anvin" <hpa at zytor.com> writes:
> 
> > On 06/03/2014 02:59 AM, Ady wrote:
> >
> >> Testing Syslinux 6.03-pre13 in a BIOS 32-bit VM,
> >> boot: vesa.c32
> >> Undef symbol FAIL: luaL_checklstring
> >> Failed to load COM32 file vesa.c32
> >> boot:
> >> 
> >> Is there a Lua-related issue?
> >> 
> >> Is vesa.c32 expecting some kind of argument?
> >
> > luaL_checklstring should be found in liblua.c32.  Are you perhaps
> > missing the latter?
> 
> Vesa.c32 is not an executable module, but a dynamically loaded binary
> Lua module, to be require()d.  However, the Syslinux module system does
> not make this distinction, so it happily tries to execute it.  Also, the
> build system is not really prepared for this (and my linker fu is rather
> weak).  For example its ELF headers show the need for libcom32.c32,
> which is probably also superfluous, as the Lua interpreter (lua.c32)
> provides that as well (just like luaL_checklstring via liblua.c32).
> 
> > I didn't realize how many modules there are in Lua, and quite frankly
> > not all of them are very well named in the sense that it is clear that
> > they are Lua-related.  vesa.c32 is one of those - it is one of several
> > Lua modules.
> 
> Their names appear in Lua code, like eg. require "vesa", so it's not
> arbitrary, but the file names can be prefixed transparently.  Currently
> (with /extlinux as install path and PATH /lua specified in the config):
> 
> > print (package.cpath)
> /lua/?.c32;/lua/?/init.c32;/extlinux/?.c32;/extlinux/?/init.c32;./?.c32
> 
> The question marks above are replaced by the argument of require().
> This variable is preset by setpath() at com32/lua/src/loadlib.c:674,
> where some string could be inserted before the question marks, or
> LUA_CPATH_DEFAULT (in luaconf.h) could be set to _lua.c32 instead of
> simply .c32 to have some extra suffix.
> -- 
> Regards,
> Feri.
> 

Please avoid using file names longer than really necessary. Just as 
an example (which has nothing to do with Lua) "localboot.c32" is 
unnecessarily not fiting "8.3" format.

TIA,
Ady.