Re: Embedding Kepler in Windows application

[Wesley Smith <wesley.hoke@...>]

yes.  not sure where my head was.  Anyway, have a C function like
ring_register_initializer(lua_CFunction) would be nice.

wes

On Wed, Feb 3, 2010 at 3:36 PM, Fabio Mascarenhas <mascarenhas@acm.org> wrote:
> Wouldn't be hard to do if it is a C function. Lua functions are a bigger
> problem, as they are not easily passed between states... string.dump will
> only serialize Lua functions without upvalues.
> If you want to initialize a state Lua code you can always call
> state:dostring right after creating the state, no?
> --
> Fabio Mascarenhas
>
>
> On Wed, Feb 3, 2010 at 3:51 PM, Wesley Smith <wesley.hoke@gmail.com> wrote:
>>
>> Hi Fabio,
>> Thanks for chiming in.  I'm wondering if it's possible to just set a
>> loader function even without a compile-time option.  Suppose one wants
>> to use a Lua function as the loader or perhaps change it dynamically?
>>
>> wes
>>
>> On Wed, Feb 3, 2010 at 8:48 AM, Fabio Mascarenhas <mascarenhas@acm.org>
>> wrote:
>> > 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...
>> >>>>
>> >>>>
>> >
>> >
>
>