Re: Building Lua 5.3 from Lua.org on FreeBSD

[Russell Haley <russ.haley@...>]

On Sat, Jul 29, 2017 at 10:00 AM, Russell Haley <russ.haley@gmail.com> wrote:
> On Fri, Jul 28, 2017 at 9:05 AM, Luiz Henrique de Figueiredo
> <lhf@tecgraf.puc-rio.br> wrote:
>>> I try to draw attention to the inconsistency, especially since you
>>> went to the trouble to make a target for FreeBSD.
>>
>> I'd love if we could make the bsd and freebsd targets the same:
>>
>> bsd:
>>         $(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-Wl,-E"
>>
>>
>> freebsd:
>>         $(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -lreadline"
>>
>> Currently, the difference is just support for LUA_USE_READLINE.
>> Any bsd experts around? Does the bsd target work in freebsd or vice-versa?
>>
>> Support for readline is the major source of noise in the Makefile,
>> even in Linux. It currently requires that the readline headers be
>> installed, and they come from a dev package which is not in the default
>> installation.
>>
>>> A mathematician's solution would be to generalize, Linux, Max OSX and
>>> FreeBSD all being special cases of OSIX (something not quite POSIX,
>>> get it?) Then LUA_USE_OSIX offends no one and is understood by
>>> no one. Fair enough?
>>
>> I'd love if all *ix system were the same and reduce the targets to
>> posix and ix, but alas life is not simple. Not even POSIX systems are
>> the same: some support for dynamic loading, some don't. Some that do,
>> required -ldl, others don't. Some require "-Wl,-E", others don't. Hence
>> the many variations:
>>
>> bsd:
>>         SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-Wl,-E"
>>
>> freebsd:
>>         SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -lreadline"
>>
>> linux:
>>         SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -ldl -lreadline"
>>
>> macosx:
>>         SYSCFLAGS="-DLUA_USE_MACOSX" SYSLIBS="-lreadline" CC=cc
>>
>> posix:
>>         SYSCFLAGS="-DLUA_USE_POSIX"
>>
>> solaris:
>>         SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN -D_REENTRANT" SYSLIBS="-ldl"
>>
>> I'd love to reduce the number of targets if this would reduce noise
>> and at the same time worked in many platforms. But I don't know how.
>> I welcome concrete suggestions from those who have access to these
>> platforms.
>
> 1)The Dream:
>
> As I am unfamiliar with readline and the code that is involved in the
> user interface, I am free from the pesky details of reality to ask
> this question:
>
> It seems to me that the Lua command line interpreter would have very
> few requirements and a library like readline would be rather
> over-engineered for more complex requirements. Is there any reason you
> don't just write your own (or steal from readline) library and be done
> with it?
>
> Then, if the defines are flipped on their head and there is one define
> for LUA_USE_WINDOWS, the LUA_USE_POSIX and LUA_USE_DLOPEN could
> potentially be removed as it's common to all.
>
>
> 2) Other Platforms:
>
> Solaris
> I've also been scouring Solaris man pages for details about dlopen:
>
> dlopen(3)
> http://docs.oracle.com/cd/E19253-01/816-5168/6mbb3hr6v/index.html
>
> ld(1)
> http://docs.oracle.com/cd/E19253-01/816-5165/ld.so.1-1/index.html
>
> Linker and Libraries Guide
> http://docs.oracle.com/cd/E19253-01/817-1984/chapter3-1/index.html
>
>
> Burried way down in the middle of the Linker and Library Guide:
>
> "Note –
>
> In previous releases of the Solaris OS, the dynamic linking interfaces
> were made available by the shared object libdl.so.1. libdl.so.1
> remains available to support any existing dependencies. However, the
> dynamic linking interfaces offered by libdl.so.1 are now available
> from libc.so.1. Linking with -ldl is no longer necessary."
>
> So potentially Linux is the only platform that requires -ldl.
>
> AIX
> I am looking at the AIX 7.2 documentation and I don't see anything
> either way. A search for -ldl provided no clarification. However
> documentation seems to indicate -b[rlt] is still required when a *.so
> object is used.
>
> https://www.ibm.com/support/knowledgecenter/ssw_aix_72/com.ibm.aix.cmds3/ld.htm
>
> "Libraries are files whose names end in .a, or possibly .so. To
> designate a library, you can specify an absolute or relative path name
> or use the -l (lowercase letter L) flag in the form -lName. The last
> form designates a libName.a file, or when the rtl option is used, a
> libName.so file to be searched for in several directories. These
> search directories include any directories that are specified by -L
> flags and the standard library directories /usr/lib and /lib.Libraries
> are files whose names end in .a, or possibly .so. To designate a
> library, you can specify an absolute or relative path name or use the
> -l (lowercase letter L) flag in the form -lName. The last form
> designates a libName.a file, or when the rtl option is used, a
> libName.so file to be searched for in several directories. These
> search directories include any directories that are specified by -L
> flags and the standard library directories /usr/lib and /lib."
>
>
> 3) Makefile Re-organization:
> Once again, I'll throw an idea out there that I have no experience to
> back. What about moving more esoteric targets such as AIX and Solaris
> out of the main makefile together? Then there would be only two
> potential targets in the main makefile: One for Windows and one for
> common *Nix patforms. The main makefile could be linked to a second
> makefile that contains targets specific to Solaris, AIX (and I
> potentially want to add MINIX3 and RTEMS to the list).
>
>
> 4) Windows Target:
> I also think that a target for Windows should use the Windows compiler
> and tools (i.e. msbuild, VC etc) if possible (without having to
> purchase Visual Studio). However, that's a different can of worms (and
> a different project!
> https://github.com/RussellHaley/PUC-Lua-VS2017-Solution/tree/master/lua-5.3.4/Visual%20Studio
> -> still can't build the main lua library as a .dll?).
>
> Also, Linux Subsystem For Windows may provide a future path for Lua to
> use *Nix targets effectively. I predict(guess) that as Open Source
> *Nix gains more traction (yes, GNU/Linux. grumble), Microsoft will
> abandon their own kernel with the first announcement sometime in the
> next 5-7 years.
>
> For what It's Worth,
>
> Russ

Hmmm... What about a short configure script? Detect the OS, compiler
and update makefile?

./configure && make

The windows side is easy because it's a configure.bat file.

C:\lua\src> config.bat
Done.
...

Russ