summaryrefslogtreecommitdiff
path: root/upb/bindings/lua/upb.lua
blob: bda9dfee398a9fde822867460aa46be155675aed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
--
-- upb - a minimalist implementation of protocol buffers.
--
-- Copyright (c) 2009 Google Inc.  See LICENSE for details.
-- Author: Josh Haberman <jhaberman@gmail.com>
--
-- Pure-Lua support functions that are part of the "upb" module.
-- This file is embedded and packaged into the "upb" C module binary -- it
-- should not be installed or used directly!

return function(upb)
  -- A convenience function for building/linking/freezing defs
  -- while maintaining their original order.
  --
  -- Sample usage:
  --   local m1, m2 = upb.build_defs{
  --     upb.MessageDef{full_name = "M1", fields = {
  --         upb.FieldDef{
  --           name = "m2",
  --           number = 1,
  --           type = upb.TYPE_MESSAGE,
  --           subdef_name = ".M2"
  --         },
  --       }
  --     },
  --     upb.MessageDef{full_name = "M2"}
  --   }
  upb.build_defs = function(defs)
    upb.SymbolTable(defs)
    -- Lua 5.2 puts unpack in the table library.
    return (unpack or table.unpack)(defs)
  end

  local ipairs_iter = function(array, last_index)
    local next_index = last_index + 1
    if next_index > #array then
      return nil
    end
    return next_index, array[next_index]
  end

  -- For iterating over the indexes and values of a upb.Array.
  --
  -- for i, val in upb.ipairs(array) do
  --   -- ...
  -- end
  upb.ipairs = function(array)
    return ipairs_iter, array, 0
  end

  local set_named = function(obj, init)
    for k, v in pairs(init) do
      local func = obj["set_" .. k]
      if not func then
        error("Cannot set member: " .. k)
      end
      func(obj, v)
    end
  end

  -- Capture references to the functions we're wrapping.
  local RealFieldDef = upb.FieldDef
  local RealEnumDef = upb.EnumDef
  local RealMessageDef = upb.MessageDef
  local RealSymbolTable = upb.SymbolTable

  -- FieldDef constructor; a wrapper around the real constructor that can
  -- set initial properties.
  --
  -- User can specify initialization values like so:
  --   upb.FieldDef{label=upb.LABEL_REQUIRED, name="my_field", number=5,
  --                type=upb.TYPE_INT32, default_value=12, type_name="Foo"}
  upb.FieldDef = function(init)
    local f = RealFieldDef()

    if init then
      -- Other members are often dependent on type, so set that first.
      if init.type then
        f:set_type(init.type)
        init.type = nil
      end

      set_named(f, init)
    end

    return f
  end


  -- MessageDef constructor; a wrapper around the real constructor that can
  -- set initial properties.
  --
  -- User can specify initialization values like so:
  --   upb.MessageDef{full_name="MyMessage", extstart=8000, fields={...}}
  upb.MessageDef = function(init)
    local m = RealMessageDef()

    if init then
      for _, f in pairs(init.fields or {}) do
        m:add(f)
      end
      init.fields = nil

      set_named(m, init)
    end

    return m
  end

  -- EnumDef constructor; a wrapper around the real constructor that can
  -- set initial properties.
  --
  -- User can specify initialization values like so:
  --   upb.EnumDef{full_name="MyEnum",
  --     values={
  --       {"FOO_VALUE_1", 1},
  --       {"FOO_VALUE_2", 2}
  --     }
  --   }
  upb.EnumDef = function(init)
    local e = RealEnumDef()

    if init then
      for _, val in pairs(init.values or {}) do
        e:add(val[1], val[2])
      end
      init.values = nil

      set_named(e, init)
    end

    return e
  end

  -- SymbolTable constructor; a wrapper around the real constructor that can
  -- add an initial set of defs.
  upb.SymbolTable = function(defs)
    local s = RealSymbolTable()

    if defs then
      s:add(defs)
    end

    return s
  end
end
generated by cgit on debian on lair
contact matthew@masot.net with questions or feedback