use module unicode flag for using unicode on dir and attributes

[sonoro1234]

local lfs = require"lfs_ffi"
lfs.unicode = true
for file in lfs.dir([[c:/luaGL/frames_anima/luajit_test/]]) do print(file);print(file:byte(1,#file)) end

things left mkdir, chdir ,set correct MAX_PATH and do winx64 also

Also corrected a problem when compiling with mingw64 (32 bits) where _findfirst32 is exported as _findfirst
Solution was trying with pcall

Appveyor test is failing for x64 but I only changed x32

[spacewander]

First of all, thanks for your pull request.

Unfortunately, the Windows support of this luafilesystem is far from perfect. To be honest, I consider this luafilesystem is just a toy project.

The root cause is, Windows (and other OS) deeply use macros to hide the platform difference, and LuaJIT FFI can't detect these macros.

Take _stat as an example. Here is a piece of sys/stat.h from Windows:

/*
 * We have to have same name for structure and the fuction so as to do the
 * macro magic.we need the structure name and function name the same.
 */
#define __stat64    _stat64

#ifdef _USE_32BIT_TIME_T
#define _fstat      _fstat32
#define _fstati64   _fstat32i64
#define _stat       _stat32
#define _stati64    _stat32i64
#define _wstat      _wstat32
#define _wstati64   _wstat32i64

#else
#define _fstat      _fstat64i32
#define _fstati64   _fstat64
#define _stat       _stat64i32
#define _stati64    _stat64
#define _wstat      _wstat64i32
#define _wstati64   _wstat64

#endif

The _stat is either _stat32 or _stat64i32, depended on the value of _USE_32BIT_TIME_T. However, _USE_32BIT_TIME_T is a macro, which is invisible in LuaJIT FFI.

We could make a guess. With pcall, we cound guess again and again. But the solution is far from perfect. Admittedly, the vanilla luafilesystem works better in such situation.

[sonoro1234]

Yes but vanilla luafilesystem is not using unicode in windows. There is a pull request for this but it seems unattended!!

[sonoro1234]

also according to https://msdn.microsoft.com/es-es/library/14h5k7ff.aspx
_stat64 is not dependent on _USE_32BIT_TIME_T

[spacewander]

@sonoro1234
I just replace _stat64i32 to _stat64, thanks for your advice!

[sonoro1234]

In case you use windows: How are you dealing with chinese caracters in file names or paths with lfs?

[spacewander]

Actually I am a server-side programmer. I use LuaJIT within OpenResty. If I have to handle unicode characters, I perfer to write scripts in Python 3 or Ruby, which have good unicode support.
Sorry for no useful information given.

[spacewander]

@sonoro1234
I have applied your fix as commit 1a99db2 and updated the fix to support LuaJIT 2.0 in 9c519dc