Re: Embedding Kepler in Windows application

[Fabio Mascarenhas <mascarenhas@...>]

Hi,

I can add a compile-time option to Rings to replace the current initialization (just a call to luaL_openlibs) with anything you want, so you could define a function like

static void myapp_initializestate(lua_State *L) {

  luaL_openlibs(L);

  /* do stuff with loaders, preload etc. */

}

and then compile rings with -DRINGS_INITIALIZE=myapp_initializestate. What do you think?

--
Fabio Mascarenhas

On Tue, Feb 2, 2010 at 9:07 AM, Папенков Николай <papenkov@t-i-l.ru> wrote:

Ok, thanks for fast reply. I forget to say preferred solution would be the one that do not modify source code neither Lua itself nor Rings, for example using only their public API. Anyway, I get the idea of your solution. There are chances that it'll be a base for our solution.

It seems to me that non-standard Lua loaders written in C is not comaptible with Rings without some form of 'source code hacking'. Am I right? Is this by design?

On 02.02.2010 14:20, Wesley Smith wrote:

We solved this problem in our app by providing a function to init
package.preload  Every slave state created by rings gets this run on
it and consequently has access to all of the C Lua modules embedded in
our app.  To make this more concrete, here's the code that gets run on
every state:

void luaav_install_modules(lua_State * L) {

       std::map<std::string, lua_CFunction>::iterator it;
       
       // main libs:
       for (it = mainmodules.begin(); it != mainmodules.end(); it++) {
               const char * name = it->first.c_str();
               lua_CFunction func = it->second;
               lua_pushcfunction(L, func);
               lua_pushstring(L, name);
               if (lua_pcall(L, 1, 1, 0))
                       printf("loadlib error: %s", lua_tostring(L, -1));
               lua_settop(L, 0);              
       }
       lua_settop(L, 0);
       
       // opt libs:
       for (it = optmodules.begin(); it != optmodules.end(); it++) {
               const char * name = it->first.c_str();
               lua_CFunction func = it->second;
               lua_getglobal(L, "package");
               lua_getfield(L, -1, "preload");
               lua_pushcfunction(L, func);
               lua_setfield(L, -2, name);
               lua_settop(L, 0);      
       }
       lua_settop(L, 0);
       
}

On Tue, Feb 2, 2010 at 4:05 AM, Папенков Николай<papenkov@t-i-l.ru>  wrote:
 

Hello, list!

That's the problem we are facing some time ago.

Some time ago we decided to embed Kepler in Windows application to provide
web access to it. We embedded Kepler sources (and all dependencies) as
resources in the application. To support loading such modules from resources
we supply new loader which replace standard loaders. That loader written in
C because it uses WinAPI to access resources in executable.

And this is where the problem arise. Slave Lua states, which created by
Rings, do not have our loaders. That's breaks loading of needed modules for
slave state.

Is there any means to put new loader in slave state? That's not a problem if
loader written in Lua. Is it possible to transfer 'package.loaders' table
from master state to a slave state? Any solution or workaround?

Thanks in advance, and sorry for English )

P.S. It'll be very sorry if we must change from Kepler to anything else...