lib.yang.list: use lib.yang.ctype

This ensures that structs inherit lib.yang.ctype's structural typing
properties.

Note: this removes a bunch of ((packed)) __attribute__s.
Have to be careful about hashing.

src/lib/yang/list.lua

@@ -2,6 +2,7 @@
 -- COPYING.
 module(..., package.seeall)
 
+local typeof = require("lib.yang.ctype").typeof
 local murmur = require("lib.hash.murmur")
 local lib = require("core.lib")
 local ffi = require("ffi")
@@ -342,30 +343,23 @@ function List:type_info (type)
  return assert(self.type_map[type], "Unsupported type: "..type)
 end
 
-List.type_cache = {}
-
-function List:cached_type (t)
- if not self.type_cache[t] then
- self.type_cache[t] = ffi.typeof(t)
- end
- return self.type_cache[t]
-end
-
-List.node_t = List:cached_type [[
+List.node_t = ffi.typeof [[
  struct {
- uint16_t occupied, leaf;
+ uint16_t occupied;
+ uint16_t leaf;
  uint32_t parent;
  uint32_t children[16];
  }
 ]]
 
 List.list_ts = [[
  struct {
- uint32_t prev, next;
+ uint32_t prev;
+ uint32_t next;
  }
 ]]
 
-List.string_t = List:cached_type [[
+List.string_t = ffi.typeof [[
  struct {
  uint16_t len;
  uint8_t str[1];
@@ -376,7 +370,15 @@ List.optional_ts = [[
  struct {
  struct { %s %s; } value;
  bool present;
- } __attribute__((packed))
+ }
+]]
+
+List.leaf_ts = [[
+ struct {
+ %s list;
+ %s keys;
+ %s members;
+ }
 ]]
 
 function List:_new (keys, members)
@@ -388,8 +390,8 @@ function List:_new (keys, members)
  local members_ts = self:build_type(members)
  self.keys = keys
  self.members = members
- self.keys_t = self:cached_type(keys_ts)
- self.leaf_t = self:cached_type(self:build_leaf_type(keys_ts, members_ts))
+ self.keys_t = typeof(keys_ts)
+ self.leaf_t = typeof(self:build_leaf_type(keys_ts, members_ts))
  self.hashin = self.keys_t()
  return self
 end
@@ -445,13 +447,12 @@ function List:build_type (fields)
  end
  t = t..("%s %s; "):format(ct, name)
  end
- t = t.."} __attribute__((packed))"
+ t = t.."}"
  return t
 end
 
 function List:build_leaf_type (keys_ts, members_ts)
- return ("struct { %s list; %s keys; %s members; } __attribute__((packed))")
- :format(self.list_ts, keys_ts, members_ts)
+ return self.leaf_ts:format(self.list_ts, keys_ts, members_ts)
 end
 
 function List:heap_cast (t, o)
@@ -1144,9 +1145,10 @@ function selftest_list ()
  assert(l.lvalues.o[1].bar == false)
 
  -- Test struct
+ local ts = "struct { uint16_t x; uint16_t y; }"
  local l = List:new(
  {id={type='string'}},
- {value={type='struct', ts="struct { uint16_t x, y; }"}}
+ {value={type='struct', ts=ts}}
  )
  l:add_entry {id="foo", value={x=1, y=2}}
  l:add_entry {id="foo1", value={x=2, y=3}}
@@ -1164,7 +1166,7 @@ function selftest_list ()
  -- Test optional struct
  local l = List:new(
  {id={type='string'}},
- {value={type='struct', ts="struct { uint16_t x, y; }", optional=true}}
+ {value={type='struct', ts=ts, optional=true}}
  )
  l:add_entry {id="foo"}
  l:add_entry {id="foo1", value={x=2, y=3}}