diff options
Diffstat (limited to 'script/json.lua')
| -rw-r--r-- | script/json.lua | 141 |
1 files changed, 85 insertions, 56 deletions
diff --git a/script/json.lua b/script/json.lua index 6390e5f0..0d3e6b48 100644 --- a/script/json.lua +++ b/script/json.lua @@ -1,4 +1,3 @@ -local pairs = pairs local type = type local next = next local error = error @@ -16,15 +15,17 @@ local string_sub = string.sub local string_format = string.format local math_type = math.type local setmetatable = setmetatable +local getmetatable = getmetatable local Inf = math.huge local json = {} -json.null = function() end json.object = {} -- json.encode -- +local statusMark +local statusQue -local encode +local encode_map = {} local encode_escape_map = { [ "\"" ] = "\\\"", @@ -39,7 +40,7 @@ local encode_escape_map = { local decode_escape_set = {} local decode_escape_map = {} -for k, v in pairs(encode_escape_map) do +for k, v in next, encode_escape_map do decode_escape_map[v] = k decode_escape_set[string_byte(v, 2)] = true end @@ -51,20 +52,19 @@ for i = 0, 31 do end end -local function encode_nil() - return "null" +local function encode(v) + local res = encode_map[type(v)](v) + statusQue[#statusQue+1] = res end -local function encode_null(val) - if val == json.null then - return "null" - end - error "cannot serialise function: type not supported" +encode_map["nil"] = function () + return "null" end -local function encode_string(val) - return '"' .. string_gsub(val, '[\0-\31\\"/]', encode_escape_map) .. '"' +function encode_map.string(v) + return '"' .. string_gsub(v, '[\0-\31\\"/]', encode_escape_map) .. '"' end +local encode_string = encode_map.string local function convertreal(v) local g = string_format('%.16g', v) @@ -74,75 +74,97 @@ local function convertreal(v) return string_format('%.17g', v) end -local function encode_number(val) - if val ~= val or val <= -Inf or val >= Inf then - error("unexpected number value '" .. tostring(val) .. "'") +function encode_map.number(v) + if v ~= v or v <= -Inf or v >= Inf then + error("unexpected number value '" .. tostring(v) .. "'") end - return string_gsub(convertreal(val), ',', '.') + return string_gsub(convertreal(v), ',', '.') end -local function encode_table(val, mark) - local first_val = next(val) +function encode_map.boolean(v) + if v then + return "true" + else + return "false" + end +end + +function encode_map.table(t) + local first_val = next(t) if first_val == nil then - if getmetatable(val) == json.object then + if getmetatable(t) == json.object then return "{}" else return "[]" end end - mark = mark or {} - if mark[val] then + if statusMark[t] then error("circular reference") end - mark[val] = true - local res = {} + statusMark[t] = true if type(first_val) == 'string' then local key = {} - for k in pairs(val) do + for k in next, t do if type(k) ~= "string" then error("invalid table: mixed or invalid key types") end key[#key+1] = k end table_sort(key) - for i = 1, #key do + statusQue[#statusQue+1] = "{" + local k = key[1] + statusQue[#statusQue+1] = encode_string(k) + statusQue[#statusQue+1] = ":" + encode(t[k]) + for i = 2, #key do local k = key[i] - res[i] = encode_string(k) .. ":" .. encode(val[k], mark) + statusQue[#statusQue+1] = "," + statusQue[#statusQue+1] = encode_string(k) + statusQue[#statusQue+1] = ":" + encode(t[k]) end - mark[val] = nil - return "{" .. table_concat(res, ",") .. "}" + statusMark[t] = nil + return "}" else local max = 0 - for k in pairs(val) do - if math_type(k) ~= "integer" then + for k in next, t do + if math_type(k) ~= "integer" or k <= 0 then error("invalid table: mixed or invalid key types") end - max = max > k and max or k + if max < k then + max = k + end end - for i = 1, max do - res[i] = encode(val[i], mark) + statusQue[#statusQue+1] = "[" + encode(t[1]) + for i = 2, max do + statusQue[#statusQue+1] = "," + encode(t[i]) end - mark[val] = nil - return "[" .. table_concat(res, ",") .. "]" + statusMark[t] = nil + return "]" end end -local encode_map = { - [ "nil" ] = encode_nil, - [ "table" ] = encode_table, - [ "string" ] = encode_string, - [ "number" ] = encode_number, - [ "boolean" ] = tostring, - [ "function" ] = encode_null, - [ "userdata" ] = function () error("unexpected type 'userdata'") end, - [ "thread" ] = function () error("unexpected type 'thread'") end, -} - -encode = function(val, mark) - return encode_map[type(val)](val, mark) +local function encode_unexpected(v) + if v == json.null then + return "null" + else + error("unexpected type '"..type(v).."'") + end +end +encode_map[ "function" ] = encode_unexpected +encode_map[ "userdata" ] = encode_unexpected +encode_map[ "thread" ] = encode_unexpected + +function json.encode(v) + statusMark = {} + statusQue = {} + encode(v) + return table_concat(statusQue) end -json.encode = encode +json.encode_map = encode_map -- json.decode -- @@ -186,6 +208,14 @@ local function next_byte() decode_error("unexpected character '<eol>'") end +local function expect_byte(c) + local _, pos = string_find(statusBuf, c, statusPos) + if not pos then + decode_error(string_format("expected '%s'", string_sub(c, #c))) + end + statusPos = pos +end + local function decode_unicode_surrogate(s1, s2) return utf8_char(0x10000 + (tonumber(s1, 16) - 0xd800) * 0x400 + (tonumber(s2, 16) - 0xdc00)) end @@ -375,13 +405,9 @@ local function decode_item() if statusAry[top] then ref[#ref+1] = decode() else - if next_byte() ~= 34 --[[ '"' ]] then - decode_error "expected string for key" - end + expect_byte '^[ \t\r\n]*"' local key = decode_string() - if next_byte() ~= 58 --[[ ":" ]] then - decode_error "expected ':' after key" - end + expect_byte '^[ \t\r\n]*:' statusPos = statusPos + 1 ref[key] = decode() end @@ -418,4 +444,7 @@ function json.decode(str) return res end +-- Generate a lightuserdata +json.null = debug.upvalueid(decode, 1) + return json |