No longer possible to get the lua_State from a uv_loop_t

[Timothy-]

The macro defined here is incorrect:

luv/src/luv.h

Line 100 in 8a04eeb

#define luv_state(L) (luv_context(L)->L)

In the following example:
lua_State *L = luv_state(uv_req->loop);
will be expanded to:
lua_State *L = (luv_context(uv_req->loop)->uv_req->loop));
causing:
error: 'luv_ctx_t' has no member named 'uv_req'

An improvement would be:
#define luv_state(loop) (luv_context(loop)->L)

Secondly, since luv_context requires lua_State as an argument this macro can no longer be used to go from a uv_loop_t to a lua_State and is effectively useless. If possible I would like the old behaviour back.

[squeek502]

Secondly, since luv_context requires lua_State as an argument this macro can no longer be used to go from a uv_loop_t to a lua_State and is effectively useless. If possible I would like the old behaviour back.

As far as I understand, this is no longer possible, as each lua_State* can now have a custom uv_loop_t*, and uv_loop_t* itself does not store any information about a lua_State*.

Relevant PRs/issues:

• How to use exists uv_loop_t . #252
• Try to support extern uv_loop_t #325 and Refactoring the code to get the loop #327 (first attempt at How to use exists uv_loop_t . #252, was ultimately reverted)
• Implement support for external uv_loop_t #331 (second attempt at How to use exists uv_loop_t . #252, was merged)
• Speed up by reduce regristry table queries #348 (introduced luv_context)

[squeek502]

Re-opening this in case we want to try to make it possible to get a lua_State* from a uv_loop_t* again.