[lxc-devel] [PATCH] lua: prepare for Lua 5.2

[Dwight Engen]

On Thu,  5 Sep 2013 08:45:33 +0200
Natanael Copa <ncopa at alpinelinux.org> wrote:

> Adjust code for Lua 5.2 and keep compatibility with Lua 5.1.
> 
> We also fix a bug in the parsing of /proc/mounts while here.

After some discussion on IRC, we decided the bug fix should be split
out. There is also one more change needed below...
 
> Signed-off-by: Natanael Copa <ncopa at alpinelinux.org>
> ---
>  src/lua-lxc/core.c  | 10 ++++++++--
>  src/lua-lxc/lxc.lua | 18 ++++++++++++++----
>  2 files changed, 22 insertions(+), 6 deletions(-)
> 
> diff --git a/src/lua-lxc/core.c b/src/lua-lxc/core.c
> index 9ccbab4..d404707 100644
> --- a/src/lua-lxc/core.c
> +++ b/src/lua-lxc/core.c
> @@ -25,9 +25,15 @@
>  #define _GNU_SOURCE
>  #include <lua.h>
>  #include <lauxlib.h>
> +#include <assert.h>
>  #include <string.h>
>  #include <lxc/lxccontainer.h>
>  
> +#if LUA_VERSION_NUM < 502
> +#define luaL_newlib(L,l) (lua_newtable(L), luaL_register(L,NULL,l))
> +#define luaL_setfuncs(L,l,n) (assert(n==0), luaL_register(L,NULL,l))
> +#endif
> +
>  #ifdef NO_CHECK_UDATA
>  #define checkudata(L,i,tname)	lua_touserdata(L, i)
>  #else
> @@ -389,7 +395,7 @@ static int lxc_lib_uninit(lua_State *L) {
>  LUALIB_API int luaopen_lxc_core(lua_State *L) {
>      /* this is where we would initialize liblxc.so if we needed to */
>  
> -    luaL_register(L, "lxc", lxc_lib_methods);
> +    luaL_newlib(L, lxc_lib_methods);
>  
>      lua_newuserdata(L, 0);
>      lua_newtable(L);  /* metatable */
> @@ -401,12 +407,12 @@ LUALIB_API int luaopen_lxc_core(lua_State *L) {
>      lua_rawset(L, -3);
>  
>      luaL_newmetatable(L, CONTAINER_TYPENAME);
> +    luaL_setfuncs(L, lxc_container_methods, 0);
>      lua_pushvalue(L, -1);  /* push metatable */
>      lua_pushstring(L, "__gc");
>      lua_pushcfunction(L, container_gc);
>      lua_settable(L, -3);
>      lua_setfield(L, -2, "__index");  /* metatable.__index =
> metatable */
> -    luaL_register(L, NULL, lxc_container_methods);
>      lua_pop(L, 1);
>      return 1;
>  }
> diff --git a/src/lua-lxc/lxc.lua b/src/lua-lxc/lxc.lua
> index b48eb76..4ef1ff9 100755
> --- a/src/lua-lxc/lxc.lua
> +++ b/src/lua-lxc/lxc.lua
> @@ -32,6 +32,11 @@ local lxc_path
>  local cgroup_path
>  local log_level = 3
>  
> +-- lua 5.1 compat
> +if table.unpack == nil then
> +    table.unpack = unpack
> +end
> +
>  -- the following two functions can be useful for debugging
>  function printf(...)
>      local function wrapper(...) io.write(string.format(...)) end
> @@ -89,6 +94,9 @@ function cgroup_path_get()
>  	while true do
>  	    local c
>  	    line = f:read()
> +	    if line == nil then
> +	        break
> +	    end
>  	    c = line:split(" ", 6)
>  	    if (c[1] == "cgroup") then
>  		cgroup_path = dirname(c[2])
> @@ -283,7 +291,7 @@ function container:stat_get_ints(controller,
> item, coords) table.insert(result, val)
>  	end
>      end
> -    return unpack(result)
> +    return table.unpack(result)
>  end
>  
>  -- read an integer from a cgroup file
> @@ -356,10 +364,10 @@ function container:stats_get(total)
>      return stat
>  end
>  
> -
> +local M = { container = container }

stats_clear needs to be moved here and made:

function M.stats_clear(stat)

so that it can be found.
  
>  -- return configured containers found in LXC_PATH directory
> -function containers_configured(names_only)
> +function M.containers_configured(names_only)
>      local containers = {}
>  
>      for dir in lfs.dir(lxc_path) do
> @@ -387,7 +395,7 @@ function containers_configured(names_only)
>  end
>  
>  -- return running containers found in cgroup fs
> -function containers_running(names_only)
> +function M.containers_running(names_only)
>      local containers = {}
>      local attr
>  
> @@ -423,3 +431,5 @@ end
>  
>  lxc_path = core.default_config_path_get()
>  cgroup_path = cgroup_path_get()
> +
> +return M