On Mon, Apr 9, 2018 at 5:53 PM, Chris Johns <chr...@rtems.org> wrote:
> On 10/04/2018 10:40, Gedare Bloom wrote: > > On Mon, Apr 9, 2018 at 4:17 PM, Russell Haley <russ.ha...@gmail.com > > <mailto:russ.ha...@gmail.com>> wrote: > > I'd like to start with getting other Lua scripts running. My > goal is > > to load a library called penlight that's a few dozens of > files. Is > > there a utility for creating and loading resources? I'll > also look > > at compiling the files using the luac compiler, but that's > outside > > of rtems. > > > > No worries. There is evolving support (pretty mature by now) for > dynamically > > loading object code, if that is what you mean: the Runtime Loader > (RTL). I > > don't have any experience with it though. Chris Johns is the expert on > that topic. > > > > The support is based around the standard calls 'dlopen' etc. You can load > ELF > object files. You do need a symbol table in the kernel and a simple > makefile > recipe can be found in the testsuite which works on the sparc simulator: > > https://git.rtems.org/rtems/tree/testsuites/libtests/Makefile.am#n319 > > (search for TEST_dl01 in the Makefile.am if the line has moved) > > Note, the erc32 sim does not have access to a host's file system so you > will > need to package the object files into a tar file just as the test does. > Hi Chris, good to hear from you. Yes, the non-filesystem is what I'm trying to deal with. Lua can run as C or as Lua scripts. The dlopen support is excellent and I'll look into that when I start loading C. There are many fine Lua wrappers for some of the best C tools. Since, I'm trying to load lua scripts, the tar package sounds like what I need to look at first. Lua scripts can be loaded as a 'string' buffer (char array), or from a file. Either of those methods can load a text file or a Lua VM binary. Using binary is apparently faster to load, but must be compiled for the same architecture. The run speed is the same. A simple Lua script to load a second module would look like this: local my_lib = require('mylib.init') local new_val = my_lib.dosomething() The require() function loads the file from a filesystem based on the package.path string. On my windows box, it looks like this: .\?.lua;C:\Program Files (x86)\LuaRocks\lua\?.lua;C:\Program Files (x86)\LuaRocks\lua\?\init.lua;C:\Program Files (x86)\LuaRocks\?.lua;C:\Users\russh\scripts\?\init.lua;C:\Users\russh\scripts\?.lua;C:\Users\russh;C:\Program Files (x86)\WinLua\Lua\5.3\bin\?53.dll; So, the require('mylib.init') would get translated so the '.' becomes the path separator on the filesystem, and any '?' in the package.path is replaced with the package name, eventually landing on C:\Users\russh\scripts\mylib\init.lua. Let's see how that translates to RTEMS... Thanks! Russ > > Chris >
_______________________________________________ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
