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-rw-r--r--vendor/json.lua380
1 files changed, 380 insertions, 0 deletions
diff --git a/vendor/json.lua b/vendor/json.lua
new file mode 100644
index 0000000..dda6193
--- /dev/null
+++ b/vendor/json.lua
@@ -0,0 +1,380 @@
+--
+-- json.lua
+--
+-- Copyright (c) 2015 rxi
+--
+-- This library is free software; you can redistribute it and/or modify it
+-- under the terms of the MIT license. See LICENSE for details.
+--
+
+local json = { _version = "0.1.0" }
+
+-------------------------------------------------------------------------------
+-- Encode
+-------------------------------------------------------------------------------
+
+local encode
+
+local escape_char_map = {
+ [ "\\" ] = "\\\\",
+ [ "\"" ] = "\\\"",
+ [ "\b" ] = "\\b",
+ [ "\f" ] = "\\f",
+ [ "\n" ] = "\\n",
+ [ "\r" ] = "\\r",
+ [ "\t" ] = "\\t",
+}
+
+local escape_char_map_inv = { [ "\\/" ] = "/" }
+for k, v in pairs(escape_char_map) do
+ escape_char_map_inv[v] = k
+end
+
+
+local function escape_char(c)
+ return escape_char_map[c] or string.format("\\u%04x", c:byte())
+end
+
+
+local function encode_nil(val)
+ return "null"
+end
+
+
+local function encode_table(val, stack)
+ local res = {}
+ stack = stack or {}
+
+ -- Circular reference?
+ if stack[val] then error("circular reference") end
+
+ stack[val] = true
+
+ if val[1] ~= nil or next(val) == nil then
+ -- Treat as array -- check keys are valid and it is not sparse
+ local n = 0
+ for k in pairs(val) do
+ if type(k) ~= "number" then
+ error("invalid table: mixed or invalid key types")
+ end
+ n = n + 1
+ end
+ if n ~= #val then
+ error("invalid table: sparse array")
+ end
+ -- Encode
+ for i, v in ipairs(val) do
+ table.insert(res, encode(v, stack))
+ end
+ stack[val] = nil
+ return "[" .. table.concat(res, ",") .. "]"
+
+ else
+ -- Treat as an object
+ for k, v in pairs(val) do
+ if type(k) ~= "string" then
+ error("invalid table: mixed or invalid key types")
+ end
+ table.insert(res, encode(k, stack) .. ":" .. encode(v, stack))
+ end
+ stack[val] = nil
+ return "{" .. table.concat(res, ",") .. "}"
+ end
+end
+
+
+local function encode_string(val)
+ return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"'
+end
+
+
+local function encode_number(val)
+ -- Check for NaN, -inf and inf
+ if val ~= val or val <= -math.huge or val >= math.huge then
+ error("unexpected number value '" .. tostring(val) .. "'")
+ end
+ return string.format("%.14g", val)
+end
+
+
+local type_func_map = {
+ [ "nil" ] = encode_nil,
+ [ "table" ] = encode_table,
+ [ "string" ] = encode_string,
+ [ "number" ] = encode_number,
+ [ "boolean" ] = tostring,
+}
+
+
+encode = function(val, stack)
+ local t = type(val)
+ local f = type_func_map[t]
+ if f then
+ return f(val, stack)
+ end
+ error("unexpected type '" .. t .. "'")
+end
+
+
+function json.encode(val)
+ return ( encode(val) )
+end
+
+
+-------------------------------------------------------------------------------
+-- Decode
+-------------------------------------------------------------------------------
+
+local parse
+
+local function create_set(...)
+ local res = {}
+ for i = 1, select("#", ...) do
+ res[ select(i, ...) ] = true
+ end
+ return res
+end
+
+local space_chars = create_set(" ", "\t", "\r", "\n")
+local delim_chars = create_set(" ", "\t", "\r", "\n", "]", "}", ",")
+local escape_chars = create_set("\\", "/", '"', "b", "f", "n", "r", "t", "u")
+local literals = create_set("true", "false", "null")
+
+local literal_map = {
+ [ "true" ] = true,
+ [ "false" ] = false,
+ [ "null" ] = nil,
+}
+
+
+local function next_char(str, idx, set, negate)
+ for i = idx, #str do
+ if set[str:sub(i, i)] ~= negate then
+ return i
+ end
+ end
+ return #str + 1
+end
+
+
+local function decode_error(str, idx, msg)
+ local line_count = 1
+ local col_count = 1
+ for i = 1, idx - 1 do
+ col_count = col_count + 1
+ if str:sub(i, i) == "\n" then
+ line_count = line_count + 1
+ col_count = 1
+ end
+ end
+ error( string.format("%s at line %d col %d", msg, line_count, col_count) )
+end
+
+
+local function codepoint_to_utf8(n)
+ -- http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=iws-appendixa
+ local f = math.floor
+ if n <= 0x7f then
+ return string.char(n)
+ elseif n <= 0x7ff then
+ return string.char(f(n / 64) + 192, n % 64 + 128)
+ elseif n <= 0xffff then
+ return string.char(f(n / 4096) + 224, f(n % 4096 / 64) + 128, n % 64 + 128)
+ elseif n <= 0x10ffff then
+ return string.char(f(n / 262144) + 240, f(n % 262144 / 4096) + 128,
+ f(n % 4096 / 64) + 128, n % 64 + 128)
+ end
+ error( string.format("invalid unicode codepoint '%x'", n) )
+end
+
+
+local function parse_unicode_escape(s)
+ local n1 = tonumber( s:sub(3, 6), 16 )
+ local n2 = tonumber( s:sub(9, 12), 16 )
+ -- Surrogate pair?
+ if n2 then
+ return codepoint_to_utf8((n1 - 0xd800) * 0x400 + (n2 - 0xdc00) + 0x10000)
+ else
+ return codepoint_to_utf8(n1)
+ end
+end
+
+
+local function parse_string(str, i)
+ local has_unicode_escape = false
+ local has_surrogate_escape = false
+ local has_escape = false
+ local last
+ for j = i + 1, #str do
+ local x = str:byte(j)
+
+ if x < 32 then
+ decode_error(str, j, "control character in string")
+ end
+
+ if last == 92 then -- "\\" (escape char)
+ if x == 117 then -- "u" (unicode escape sequence)
+ local hex = str:sub(j + 1, j + 5)
+ if not hex:find("%x%x%x%x") then
+ decode_error(str, j, "invalid unicode escape in string")
+ end
+ if hex:find("^[dD][89aAbB]") then
+ has_surrogate_escape = true
+ else
+ has_unicode_escape = true
+ end
+ else
+ local c = string.char(x)
+ if not escape_chars[c] then
+ decode_error(str, j, "invalid escape char '" .. c .. "' in string")
+ end
+ has_escape = true
+ end
+ last = nil
+
+ elseif x == 34 then -- '"' (end of string)
+ local s = str:sub(i + 1, j - 1)
+ if has_surrogate_escape then
+ s = s:gsub("\\u[dD][89aAbB]..\\u....", parse_unicode_escape)
+ end
+ if has_unicode_escape then
+ s = s:gsub("\\u....", parse_unicode_escape)
+ end
+ if has_escape then
+ s = s:gsub("\\.", escape_char_map_inv)
+ end
+ return s, j + 1
+
+ else
+ last = x
+ end
+ end
+ decode_error(str, i, "expected closing quote for string")
+end
+
+
+local function parse_number(str, i)
+ local x = next_char(str, i, delim_chars)
+ local s = str:sub(i, x - 1)
+ local n = tonumber(s)
+ if not n then
+ decode_error(str, i, "invalid number '" .. s .. "'")
+ end
+ return n, x
+end
+
+
+local function parse_literal(str, i)
+ local x = next_char(str, i, delim_chars)
+ local word = str:sub(i, x - 1)
+ if not literals[word] then
+ decode_error(str, i, "invalid literal '" .. word .. "'")
+ end
+ return literal_map[word], x
+end
+
+
+local function parse_array(str, i)
+ local res = {}
+ local n = 1
+ i = i + 1
+ while 1 do
+ local x
+ i = next_char(str, i, space_chars, true)
+ -- Empty / end of array?
+ if str:sub(i, i) == "]" then
+ i = i + 1
+ break
+ end
+ -- Read token
+ x, i = parse(str, i)
+ res[n] = x
+ n = n + 1
+ -- Next token
+ i = next_char(str, i, space_chars, true)
+ local chr = str:sub(i, i)
+ i = i + 1
+ if chr == "]" then break end
+ if chr ~= "," then decode_error(str, i, "expected ']' or ','") end
+ end
+ return res, i
+end
+
+
+local function parse_object(str, i)
+ local res = {}
+ i = i + 1
+ while 1 do
+ local key, val
+ i = next_char(str, i, space_chars, true)
+ -- Empty / end of object?
+ if str:sub(i, i) == "}" then
+ i = i + 1
+ break
+ end
+ -- Read key
+ if str:sub(i, i) ~= '"' then
+ decode_error(str, i, "expected string for key")
+ end
+ key, i = parse(str, i)
+ -- Read ':' delimiter
+ i = next_char(str, i, space_chars, true)
+ if str:sub(i, i) ~= ":" then
+ decode_error(str, i, "expected ':' after key")
+ end
+ i = next_char(str, i + 1, space_chars, true)
+ -- Read value
+ val, i = parse(str, i)
+ -- Set
+ res[key] = val
+ -- Next token
+ i = next_char(str, i, space_chars, true)
+ local chr = str:sub(i, i)
+ i = i + 1
+ if chr == "}" then break end
+ if chr ~= "," then decode_error(str, i, "expected '}' or ','") end
+ end
+ return res, i
+end
+
+
+local char_func_map = {
+ [ '"' ] = parse_string,
+ [ "0" ] = parse_number,
+ [ "1" ] = parse_number,
+ [ "2" ] = parse_number,
+ [ "3" ] = parse_number,
+ [ "4" ] = parse_number,
+ [ "5" ] = parse_number,
+ [ "6" ] = parse_number,
+ [ "7" ] = parse_number,
+ [ "8" ] = parse_number,
+ [ "9" ] = parse_number,
+ [ "-" ] = parse_number,
+ [ "t" ] = parse_literal,
+ [ "f" ] = parse_literal,
+ [ "n" ] = parse_literal,
+ [ "[" ] = parse_array,
+ [ "{" ] = parse_object,
+}
+
+
+parse = function(str, idx)
+ local chr = str:sub(idx, idx)
+ local f = char_func_map[chr]
+ if f then
+ return f(str, idx)
+ end
+ decode_error(str, idx, "unexpected character '" .. chr .. "'")
+end
+
+
+function json.decode(str)
+ if type(str) ~= "string" then
+ error("expected argument of type string, got " .. type(str))
+ end
+ return ( parse(str, next_char(str, 1, space_chars, true)) )
+end
+
+
+return json