Please comment on these Lua to C library bindings that I wrote

["Richard W.M. Jones" <rjones@...>]

My bindings:
http://oirase.annexia.org/tmp/lua-guestfs.c.txt

There are some examples of using them here:
http://libguestfs.org/guestfs-lua.3.html
https://github.com/libguestfs/libguestfs/tree/master/lua/tests

The bindings are generated by a custom script, hence their length.
You can ignore everything between 'lua_guestfs_add_cdrom' and
'lua_guestfs_zgrepi', which is about 90% of the file, on a first pass.

In general, it all seems to work.

However I've had some specific problems:

- How do you pass and return 64 bit ints?  (which must work with full
  64 bit precision even on 32 bit platforms)

- Is the way I've done callbacks safe?  Particularly stashing the
  lua_State pointer in a C struct for potentially a long time.
  [see lua_guestfs_set_event_callback, event_callback_wrapper]

- How do I push a userdata onto the Lua stack?  Instead I'm pushing
  a pointer to a userdata using: lua_pushlightuserdata (L, u);
  [see event_callback_wrapper]

- How do you print "any" type, from C?

- This works:
    luaL_register (L, NULL, handle_methods);
  but this fails:
    luaL_register (L, "guestfs", handle_methods);
  Why?

- Are the bindings GC-safe?  For example, I often get strings, arrays
  of strings using 'luaL_checkstring', and I'm doing stack operations
  at the same time.  Could the strings get moved (or freed) between me
  getting the pointer and me passing the pointer to the C function?
  [see get_string_list for one example]

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org