Re: XML structured script output (storing results per script instance)

[Daniel Miller <bonsaiviking () gmail com>]

On Wed, Aug 1, 2012 at 8:44 PM, Patrick Donnelly <batrick () batbytes com> wrote:
> Use luaL_unref instead of setting it to nil manually. luaL_ref also
> sets the table for you. You don't need this code:
>
> +  lua_pushvalue(lstate, pos);
> +  lua_rawseti(lstate, -2, key); /* _R[NSE_SCRIPT_RESULT][key] = return_value *

This makes sense, applied.

> luaL_newstate, but, these return a "main thread" as a lua_State (L_NSE
> is this main thread).  The threads (coroutines) that NSE creates (in
> nse_main.lua) are created using lua_newthread [1] which also returns a
> lua_State but is in the same global state. All Lua data (tables,
> LUA_REGISTRYINDEX, etc.) can be accessed from any lua_State in the
> same global state. [This is actually a pretty common confusion when it
> comes to Lua.]
>
> [1] http://www.lua.org/source/5.2/lcorolib.c.html#luaB_cocreate

I think I get it. I've attached a couple patches; does the 0030 patch
handle this correctly now? Also, I think I did the right thing in the
0031 patch in order to wrap the call in lua_pcall. Am I missing
anything there that you can see? Thanks so much for your help with
this.

> You don't need another data structure representation of the output.
> You just need to try to look at the problem as how you can let Lua do
> the heavy lifting through calls to XML for you. I believe most of our
> XML calls are already bound for you in the cnse library.

Because the call to ScriptResult::write_xml() comes from output.cc, I
really don't see how to make this an entirely-Lua problem. I would
like to, since the recursive traversal would be cleaner in Lua than in
C, but I've already got the necessary functions written, and I think
to call back to Lua from C would require stashing a Lua function
somewhere in the registry, which seems more messy than it is worth.
Thoughts?

Dan

Attachment: 0030-Use-L_NSE-instead-of-ScriptResult-lstate.patch
Description:

Attachment: 0031-Wrap-script-xml-output-in-lua_pcall.patch
Description:

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