From 303b3792f62161805fd7a40a509e66ddb76ae07b Mon Sep 17 00:00:00 2001 From: Quinlan Pfiffer Date: Mon, 17 Jul 2023 12:24:54 +0100 Subject: [PATCH] Swap out JSON implementation. --- src/JSON.lua | 1139 ++++++++++++++------------------------------------ 1 file changed, 311 insertions(+), 828 deletions(-) diff --git a/src/JSON.lua b/src/JSON.lua index 53065bb..711ef78 100644 --- a/src/JSON.lua +++ b/src/JSON.lua @@ -1,905 +1,388 @@ --- -*- coding: utf-8 -*- -- --- Simple JSON encoding and decoding in pure Lua. +-- json.lua -- --- Copyright 2010-2013 Jeffrey Friedl --- http://regex.info/blog/ +-- Copyright (c) 2020 rxi -- --- Latest version: http://regex.info/blog/lua/json +-- Permission is hereby granted, free of charge, to any person obtaining a copy of +-- this software and associated documentation files (the "Software"), to deal in +-- the Software without restriction, including without limitation the rights to +-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +-- of the Software, and to permit persons to whom the Software is furnished to do +-- so, subject to the following conditions: -- --- This code is released under a Creative Commons CC-BY "Attribution" License: --- http://creativecommons.org/licenses/by/3.0/deed.en_US +-- The above copyright notice and this permission notice shall be included in all +-- copies or substantial portions of the Software. -- --- It can be used for any purpose so long as the copyright notice and --- web-page links above are maintained. Enjoy. +-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +-- SOFTWARE. -- -local VERSION = 20140418.11 -- version history at end of file -local OBJDEF = { VERSION = VERSION } +local json = { _version = "0.1.2" } --- --- Simple JSON encoding and decoding in pure Lua. --- http://www.json.org/ --- --- --- JSON = (loadfile "JSON.lua")() -- one-time load of the routines --- --- local lua_value = JSON:decode(raw_json_text) --- --- local raw_json_text = JSON:encode(lua_table_or_value) --- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability --- --- --- DECODING --- --- JSON = (loadfile "JSON.lua")() -- one-time load of the routines --- --- local lua_value = JSON:decode(raw_json_text) --- --- If the JSON text is for an object or an array, e.g. --- { "what": "books", "count": 3 } --- or --- [ "Larry", "Curly", "Moe" ] --- --- the result is a Lua table, e.g. --- { what = "books", count = 3 } --- or --- { "Larry", "Curly", "Moe" } --- --- --- The encode and decode routines accept an optional second argument, "etc", which is not used --- during encoding or decoding, but upon error is passed along to error handlers. It can be of any --- type (including nil). --- --- With most errors during decoding, this code calls --- --- JSON:onDecodeError(message, text, location, etc) --- --- with a message about the error, and if known, the JSON text being parsed and the byte count --- where the problem was discovered. You can replace the default JSON:onDecodeError() with your --- own function. --- --- The default onDecodeError() merely augments the message with data about the text and the --- location if known (and if a second 'etc' argument had been provided to decode(), its value is --- tacked onto the message as well), and then calls JSON.assert(), which itself defaults to Lua's --- built-in assert(), and can also be overridden. --- --- For example, in an Adobe Lightroom plugin, you might use something like --- --- function JSON:onDecodeError(message, text, location, etc) --- LrErrors.throwUserError("Internal Error: invalid JSON data") --- end --- --- or even just --- --- function JSON.assert(message) --- LrErrors.throwUserError("Internal Error: " .. message) --- end --- --- If JSON:decode() is passed a nil, this is called instead: --- --- JSON:onDecodeOfNilError(message, nil, nil, etc) --- --- and if JSON:decode() is passed HTML instead of JSON, this is called: --- --- JSON:onDecodeOfHTMLError(message, text, nil, etc) --- --- The use of the fourth 'etc' argument allows stronger coordination between decoding and error --- reporting, especially when you provide your own error-handling routines. Continuing with the --- the Adobe Lightroom plugin example: --- --- function JSON:onDecodeError(message, text, location, etc) --- local note = "Internal Error: invalid JSON data" --- if type(etc) = 'table' and etc.photo then --- note = note .. " while processing for " .. etc.photo:getFormattedMetadata('fileName') --- end --- LrErrors.throwUserError(note) --- end --- --- : --- : --- --- for i, photo in ipairs(photosToProcess) do --- : --- : --- local data = JSON:decode(someJsonText, { photo = photo }) --- : --- : --- end --- --- --- --- - --- DECODING AND STRICT TYPES --- --- Because both JSON objects and JSON arrays are converted to Lua tables, it's not normally --- possible to tell which a JSON type a particular Lua table was derived from, or guarantee --- decode-encode round-trip equivalency. --- --- However, if you enable strictTypes, e.g. --- --- JSON = (loadfile "JSON.lua")() --load the routines --- JSON.strictTypes = true --- --- then the Lua table resulting from the decoding of a JSON object or JSON array is marked via Lua --- metatable, so that when re-encoded with JSON:encode() it ends up as the appropriate JSON type. --- --- (This is not the default because other routines may not work well with tables that have a --- metatable set, for example, Lightroom API calls.) --- --- --- ENCODING --- --- JSON = (loadfile "JSON.lua")() -- one-time load of the routines --- --- local raw_json_text = JSON:encode(lua_table_or_value) --- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability - --- On error during encoding, this code calls: --- --- JSON:onEncodeError(message, etc) --- --- which you can override in your local JSON object. --- --- If the Lua table contains both string and numeric keys, it fits neither JSON's --- idea of an object, nor its idea of an array. To get around this, when any string --- key exists (or when non-positive numeric keys exist), numeric keys are converted --- to strings. --- --- For example, --- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" })) --- produces the JSON object --- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"} --- --- To prohibit this conversion and instead make it an error condition, set --- JSON.noKeyConversion = true - - --- --- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT --- --- assert --- onDecodeError --- onDecodeOfNilError --- onDecodeOfHTMLError --- onEncodeError --- --- If you want to create a separate Lua JSON object with its own error handlers, --- you can reload JSON.lua or use the :new() method. --- ---------------------------------------------------------------------------- - - -local author = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json), version " .. tostring(VERSION) .. " ]-" -local isArray = { __tostring = function() return "JSON array" end } isArray.__index = isArray -local isObject = { __tostring = function() return "JSON object" end } isObject.__index = isObject - - -function OBJDEF:newArray(tbl) - return setmetatable(tbl or {}, isArray) -end - -function OBJDEF:newObject(tbl) - return setmetatable(tbl or {}, isObject) +------------------------------------------------------------------------------- +-- 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 unicode_codepoint_as_utf8(codepoint) - -- - -- codepoint is a number - -- - if codepoint <= 127 then - return string.char(codepoint) - - elseif codepoint <= 2047 then - -- - -- 110yyyxx 10xxxxxx <-- useful notation from http://en.wikipedia.org/wiki/Utf8 - -- - local highpart = math.floor(codepoint / 0x40) - local lowpart = codepoint - (0x40 * highpart) - return string.char(0xC0 + highpart, - 0x80 + lowpart) - - elseif codepoint <= 65535 then - -- - -- 1110yyyy 10yyyyxx 10xxxxxx - -- - local highpart = math.floor(codepoint / 0x1000) - local remainder = codepoint - 0x1000 * highpart - local midpart = math.floor(remainder / 0x40) - local lowpart = remainder - 0x40 * midpart - - highpart = 0xE0 + highpart - midpart = 0x80 + midpart - lowpart = 0x80 + lowpart - - -- - -- Check for an invalid character (thanks Andy R. at Adobe). - -- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070 - -- - if ( highpart == 0xE0 and midpart < 0xA0 ) or - ( highpart == 0xED and midpart > 0x9F ) or - ( highpart == 0xF0 and midpart < 0x90 ) or - ( highpart == 0xF4 and midpart > 0x8F ) - then - return "?" - else - return string.char(highpart, - midpart, - lowpart) - end - else - -- - -- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx - -- - local highpart = math.floor(codepoint / 0x40000) - local remainder = codepoint - 0x40000 * highpart - local midA = math.floor(remainder / 0x1000) - remainder = remainder - 0x1000 * midA - local midB = math.floor(remainder / 0x40) - local lowpart = remainder - 0x40 * midB - - return string.char(0xF0 + highpart, - 0x80 + midA, - 0x80 + midB, - 0x80 + lowpart) - end +local function escape_char(c) + return "\\" .. (escape_char_map[c] or string.format("u%04x", c:byte())) end -function OBJDEF:onDecodeError(message, text, location, etc) - if text then - if location then - message = string.format("%s at char %d of: %s", message, location, text) - else - message = string.format("%s: %s", message, text) - end - end - - if etc ~= nil then - message = message .. " (" .. OBJDEF:encode(etc) .. ")" - end - if self.assert then - self.assert(false, message) - else - assert(false, message) - end +local function encode_nil(val) + return "null" end -OBJDEF.onDecodeOfNilError = OBJDEF.onDecodeError -OBJDEF.onDecodeOfHTMLError = OBJDEF.onDecodeError -function OBJDEF:onEncodeError(message, etc) - if etc ~= nil then - message = message .. " (" .. OBJDEF:encode(etc) .. ")" - end - - if self.assert then - self.assert(false, message) - else - assert(false, message) - end -end +local function encode_table(val, stack) + local res = {} + stack = stack or {} -local function grok_number(self, text, start, etc) - -- - -- Grab the integer part - -- - local integer_part = text:match('^-?[1-9]%d*', start) - or text:match("^-?0", start) + -- Circular reference? + if stack[val] then error("circular reference") end - if not integer_part then - self:onDecodeError("expected number", text, start, etc) - end - - local i = start + integer_part:len() - - -- - -- Grab an optional decimal part - -- - local decimal_part = text:match('^%.%d+', i) or "" - - i = i + decimal_part:len() - - -- - -- Grab an optional exponential part - -- - local exponent_part = text:match('^[eE][-+]?%d+', i) or "" - - i = i + exponent_part:len() - - local full_number_text = integer_part .. decimal_part .. exponent_part - local as_number = tonumber(full_number_text) - - if not as_number then - self:onDecodeError("bad number", text, start, etc) - end - - return as_number, i -end + stack[val] = true - -local function grok_string(self, text, start, etc) - - if text:sub(start,start) ~= '"' then - self:onDecodeError("expected string's opening quote", text, start, etc) - end - - local i = start + 1 -- +1 to bypass the initial quote - local text_len = text:len() - local VALUE = "" - while i <= text_len do - local c = text:sub(i,i) - if c == '"' then - return VALUE, i + 1 + if rawget(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 - if c ~= '\\' then - VALUE = VALUE .. c - i = i + 1 - elseif text:match('^\\b', i) then - VALUE = VALUE .. "\b" - i = i + 2 - elseif text:match('^\\f', i) then - VALUE = VALUE .. "\f" - i = i + 2 - elseif text:match('^\\n', i) then - VALUE = VALUE .. "\n" - i = i + 2 - elseif text:match('^\\r', i) then - VALUE = VALUE .. "\r" - i = i + 2 - elseif text:match('^\\t', i) then - VALUE = VALUE .. "\t" - i = i + 2 - else - local hex = text:match('^\\u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i) - if hex then - i = i + 6 -- bypass what we just read - - -- We have a Unicode codepoint. It could be standalone, or if in the proper range and - -- followed by another in a specific range, it'll be a two-code surrogate pair. - local codepoint = tonumber(hex, 16) - if codepoint >= 0xD800 and codepoint <= 0xDBFF then - -- it's a hi surrogate... see whether we have a following low - local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i) - if lo_surrogate then - i = i + 6 -- bypass the low surrogate we just read - codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16) - else - -- not a proper low, so we'll just leave the first codepoint as is and spit it out. - end - end - VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint) - - else - - -- just pass through what's escaped - VALUE = VALUE .. text:match('^\\(.)', i) - i = i + 2 - 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 - end - - self:onDecodeError("unclosed string", text, start, etc) + table.insert(res, encode(k, stack) .. ":" .. encode(v, stack)) + end + stack[val] = nil + return "{" .. table.concat(res, ",") .. "}" + end end -local function skip_whitespace(text, start) - local match_start, match_end = text:find("^[ \n\r\t]+", start) -- [http://www.ietf.org/rfc/rfc4627.txt] Section 2 - if match_end then - return match_end + 1 - else - return start - end +local function encode_string(val) + return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"' end -local grok_one -- assigned later - -local function grok_object(self, text, start, etc) - if not text:sub(start,start) == '{' then - self:onDecodeError("expected '{'", text, start, etc) - end - - local i = skip_whitespace(text, start + 1) -- +1 to skip the '{' - - local VALUE = self.strictTypes and self:newObject { } or { } - - if text:sub(i,i) == '}' then - return VALUE, i + 1 - end - local text_len = text:len() - while i <= text_len do - local key, new_i = grok_string(self, text, i, etc) - - i = skip_whitespace(text, new_i) - if text:sub(i, i) ~= ':' then - self:onDecodeError("expected colon", text, i, etc) - end - - i = skip_whitespace(text, i + 1) - - local val, new_i = grok_one(self, text, i) - - VALUE[key] = val - - -- - -- Expect now either '}' to end things, or a ',' to allow us to continue. - -- - i = skip_whitespace(text, new_i) - - local c = text:sub(i,i) - - if c == '}' then - return VALUE, i + 1 - end - - if text:sub(i, i) ~= ',' then - self:onDecodeError("expected comma or '}'", text, i, etc) - end - - i = skip_whitespace(text, i + 1) - end - - self:onDecodeError("unclosed '{'", text, start, etc) +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 function grok_array(self, text, start, etc) - if not text:sub(start,start) == '[' then - self:onDecodeError("expected '['", text, start, etc) - end - - local i = skip_whitespace(text, start + 1) -- +1 to skip the '[' - local VALUE = self.strictTypes and self:newArray { } or { } - if text:sub(i,i) == ']' then - return VALUE, i + 1 - end - - local VALUE_INDEX = 1 - - local text_len = text:len() - while i <= text_len do - local val, new_i = grok_one(self, text, i) - -- can't table.insert(VALUE, val) here because it's a no-op if val is nil - VALUE[VALUE_INDEX] = val - VALUE_INDEX = VALUE_INDEX + 1 +local type_func_map = { + [ "nil" ] = encode_nil, + [ "table" ] = encode_table, + [ "string" ] = encode_string, + [ "number" ] = encode_number, + [ "boolean" ] = tostring, +} - i = skip_whitespace(text, new_i) - -- - -- Expect now either ']' to end things, or a ',' to allow us to continue. - -- - local c = text:sub(i,i) - if c == ']' then - return VALUE, i + 1 - end - if text:sub(i, i) ~= ',' then - self:onDecodeError("expected comma or '['", text, i, etc) - end - i = skip_whitespace(text, i + 1) - end - self:onDecodeError("unclosed '['", text, start, etc) +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 -grok_one = function(self, text, start, etc) - -- Skip any whitespace - start = skip_whitespace(text, start) +function json.encode(val) + return ( encode(val) ) +end - if start > text:len() then - self:onDecodeError("unexpected end of string", text, nil, etc) - end - if text:find('^"', start) then - return grok_string(self, text, start, etc) +------------------------------------------------------------------------------- +-- Decode +------------------------------------------------------------------------------- - elseif text:find('^[-0123456789 ]', start) then - return grok_number(self, text, start, etc) +local parse - elseif text:find('^%{', start) then - return grok_object(self, text, start, etc) +local function create_set(...) + local res = {} + for i = 1, select("#", ...) do + res[ select(i, ...) ] = true + end + return res +end - elseif text:find('^%[', start) then - return grok_array(self, text, start, etc) +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 - elseif text:find('^true', start) then - return true, start + 4 - elseif text:find('^false', start) then - return false, start + 5 +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 - elseif text:find('^null', start) then - return nil, start + 4 - else - self:onDecodeError("can't parse JSON", text, start, etc) - 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 -function OBJDEF:decode(text, etc) - if type(self) ~= 'table' or self.__index ~= OBJDEF then - OBJDEF:onDecodeError("JSON:decode must be called in method format", nil, nil, etc) - end - - if text == nil then - self:onDecodeOfNilError(string.format("nil passed to JSON:decode()"), nil, nil, etc) - elseif type(text) ~= 'string' then - self:onDecodeError(string.format("expected string argument to JSON:decode(), got %s", type(text)), nil, nil, etc) - end - - if text:match('^%s*$') then - return nil - end - - if text:match('^%s*<') then - -- Can't be JSON... we'll assume it's HTML - self:onDecodeOfHTMLError(string.format("html passed to JSON:decode()"), text, nil, etc) - end - - -- - -- Ensure that it's not UTF-32 or UTF-16. - -- Those are perfectly valid encodings for JSON (as per RFC 4627 section 3), - -- but this package can't handle them. - -- - if text:sub(1,1):byte() == 0 or (text:len() >= 2 and text:sub(2,2):byte() == 0) then - self:onDecodeError("JSON package groks only UTF-8, sorry", text, nil, etc) - end - - local success, value = pcall(grok_one, self, text, 1, etc) - - if success then - return value - else - -- if JSON:onDecodeError() didn't abort out of the pcall, we'll have received the error message here as "value", so pass it along as an assert. - if self.assert then - self.assert(false, value) - else - assert(false, value) - end - -- and if we're still here, return a nil and throw the error message on as a second arg - return nil, value - end -end -local function backslash_replacement_function(c) - if c == "\n" then - return "\\n" - elseif c == "\r" then - return "\\r" - elseif c == "\t" then - return "\\t" - elseif c == "\b" then - return "\\b" - elseif c == "\f" then - return "\\f" - elseif c == '"' then - return '\\"' - elseif c == '\\' then - return '\\\\' - else - return string.format("\\u%04x", c:byte()) - end +local function parse_unicode_escape(s) + local n1 = tonumber( s:sub(1, 4), 16 ) + local n2 = tonumber( s:sub(7, 10), 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 chars_to_be_escaped_in_JSON_string - = '[' - .. '"' -- class sub-pattern to match a double quote - .. '%\\' -- class sub-pattern to match a backslash - .. '%z' -- class sub-pattern to match a null - .. '\001' .. '-' .. '\031' -- class sub-pattern to match control characters - .. ']' - -local function json_string_literal(value) - local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function) - return '"' .. newval .. '"' -end -local function object_or_array(self, T, etc) - -- - -- We need to inspect all the keys... if there are any strings, we'll convert to a JSON - -- object. If there are only numbers, it's a JSON array. - -- - -- If we'll be converting to a JSON object, we'll want to sort the keys so that the - -- end result is deterministic. - -- - local string_keys = { } - local number_keys = { } - local number_keys_must_be_strings = false - local maximum_number_key - - for key in pairs(T) do - if type(key) == 'string' then - table.insert(string_keys, key) - elseif type(key) == 'number' then - table.insert(number_keys, key) - if key <= 0 or key >= math.huge then - number_keys_must_be_strings = true - elseif not maximum_number_key or key > maximum_number_key then - maximum_number_key = key - end - else - self:onEncodeError("can't encode table with a key of type " .. type(key), etc) - end - end - - if #string_keys == 0 and not number_keys_must_be_strings then - -- - -- An empty table, or a numeric-only array - -- - if #number_keys > 0 then - return nil, maximum_number_key -- an array - elseif tostring(T) == "JSON array" then - return nil - elseif tostring(T) == "JSON object" then - return { } - else - -- have to guess, so we'll pick array, since empty arrays are likely more common than empty objects - return nil - end - end +local function parse_string(str, i) + local res = "" + local j = i + 1 + local k = j - table.sort(string_keys) + while j <= #str do + local x = str:byte(j) - local map - if #number_keys > 0 then - -- - -- If we're here then we have either mixed string/number keys, or numbers inappropriate for a JSON array - -- It's not ideal, but we'll turn the numbers into strings so that we can at least create a JSON object. - -- + if x < 32 then + decode_error(str, j, "control character in string") - if JSON.noKeyConversion then - self:onEncodeError("a table with both numeric and string keys could be an object or array; aborting", etc) + elseif x == 92 then -- `\`: Escape + res = res .. str:sub(k, j - 1) + j = j + 1 + local c = str:sub(j, j) + if c == "u" then + local hex = str:match("^[dD][89aAbB]%x%x\\u%x%x%x%x", j + 1) + or str:match("^%x%x%x%x", j + 1) + or decode_error(str, j - 1, "invalid unicode escape in string") + res = res .. parse_unicode_escape(hex) + j = j + #hex + else + if not escape_chars[c] then + decode_error(str, j - 1, "invalid escape char '" .. c .. "' in string") + end + res = res .. escape_char_map_inv[c] end + k = j + 1 - -- - -- Have to make a shallow copy of the source table so we can remap the numeric keys to be strings - -- - map = { } - for key, val in pairs(T) do - map[key] = val - end + elseif x == 34 then -- `"`: End of string + res = res .. str:sub(k, j - 1) + return res, j + 1 + end - table.sort(number_keys) - - -- - -- Throw numeric keys in there as strings - -- - for _, number_key in ipairs(number_keys) do - local string_key = tostring(number_key) - if map[string_key] == nil then - table.insert(string_keys , string_key) - map[string_key] = T[number_key] - else - self:onEncodeError("conflict converting table with mixed-type keys into a JSON object: key " .. number_key .. " exists both as a string and a number.", etc) - end - end - end + j = j + 1 + end - return string_keys, nil, map + decode_error(str, i, "expected closing quote for string") end --- --- Encode --- -local encode_value -- must predeclare because it calls itself -function encode_value(self, value, parents, etc, indent) -- non-nil indent means pretty-printing - - if value == nil then - return 'null' - - elseif type(value) == 'string' then - return json_string_literal(value) - - elseif type(value) == 'number' then - if value ~= value then - -- - -- NaN (Not a Number). - -- JSON has no NaN, so we have to fudge the best we can. This should really be a package option. - -- - return "null" - elseif value >= math.huge then - -- - -- Positive infinity. JSON has no INF, so we have to fudge the best we can. This should - -- really be a package option. Note: at least with some implementations, positive infinity - -- is both ">= math.huge" and "<= -math.huge", which makes no sense but that's how it is. - -- Negative infinity is properly "<= -math.huge". So, we must be sure to check the ">=" - -- case first. - -- - return "1e+9999" - elseif value <= -math.huge then - -- - -- Negative infinity. - -- JSON has no INF, so we have to fudge the best we can. This should really be a package option. - -- - return "-1e+9999" - else - return tostring(value) - end - - elseif type(value) == 'boolean' then - return tostring(value) - - elseif type(value) ~= 'table' then - self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc) - else - -- - -- A table to be converted to either a JSON object or array. - -- - local T = value +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 - if parents[T] then - self:onEncodeError("table " .. tostring(T) .. " is a child of itself", etc) - else - parents[T] = true - end - local result_value - - local object_keys, maximum_number_key, map = object_or_array(self, T, etc) - if maximum_number_key then - -- - -- An array... - -- - local ITEMS = { } - for i = 1, maximum_number_key do - table.insert(ITEMS, encode_value(self, T[i], parents, etc, indent)) - end - - if indent then - result_value = "[ " .. table.concat(ITEMS, ", ") .. " ]" - else - result_value = "[" .. table.concat(ITEMS, ",") .. "]" - end - - elseif object_keys then - -- - -- An object - -- - local TT = map or T - - if indent then - - local KEYS = { } - local max_key_length = 0 - for _, key in ipairs(object_keys) do - local encoded = encode_value(self, tostring(key), parents, etc, "") - max_key_length = math.max(max_key_length, #encoded) - table.insert(KEYS, encoded) - end - local key_indent = indent .. " " - local subtable_indent = indent .. string.rep(" ", max_key_length + 2 + 4) - local FORMAT = "%s%" .. string.format("%d", max_key_length) .. "s: %s" - - local COMBINED_PARTS = { } - for i, key in ipairs(object_keys) do - local encoded_val = encode_value(self, TT[key], parents, etc, subtable_indent) - table.insert(COMBINED_PARTS, string.format(FORMAT, key_indent, KEYS[i], encoded_val)) - end - result_value = "{\n" .. table.concat(COMBINED_PARTS, ",\n") .. "\n" .. indent .. "}" - - else - - local PARTS = { } - for _, key in ipairs(object_keys) do - local encoded_val = encode_value(self, TT[key], parents, etc, indent) - local encoded_key = encode_value(self, tostring(key), parents, etc, indent) - table.insert(PARTS, string.format("%s:%s", encoded_key, encoded_val)) - end - result_value = "{" .. table.concat(PARTS, ",") .. "}" - - end - else - -- - -- An empty array/object... we'll treat it as an array, though it should really be an option - -- - result_value = "[]" - end - - parents[T] = false - return result_value - 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 -function OBJDEF:encode(value, etc) - if type(self) ~= 'table' or self.__index ~= OBJDEF then - OBJDEF:onEncodeError("JSON:encode must be called in method format", etc) - end - return encode_value(self, value, {}, etc, nil) +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 -function OBJDEF:encode_pretty(value, etc) - if type(self) ~= 'table' or self.__index ~= OBJDEF then - OBJDEF:onEncodeError("JSON:encode_pretty must be called in method format", etc) - end - return encode_value(self, value, {}, etc, "") -end -function OBJDEF.__tostring() - return "JSON encode/decode package" +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 -OBJDEF.__index = OBJDEF -function OBJDEF:new(args) - local new = { } +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 - if args then - for key, val in pairs(args) do - new[key] = val - end - end - return setmetatable(new, OBJDEF) +function json.decode(str) + if type(str) ~= "string" then + error("expected argument of type string, got " .. type(str)) + end + local res, idx = parse(str, next_char(str, 1, space_chars, true)) + idx = next_char(str, idx, space_chars, true) + if idx <= #str then + decode_error(str, idx, "trailing garbage") + end + return res end -return OBJDEF:new() --- --- Version history: --- --- 20140418.11 JSON nulls embedded within an array were being ignored, such that --- ["1",null,null,null,null,null,"seven"], --- would return --- {1,"seven"} --- It's now fixed to properly return --- {1, nil, nil, nil, nil, nil, "seven"} --- Thanks to "haddock" for catching the error. --- --- 20140116.10 The user's JSON.assert() wasn't always being used. Thanks to "blue" for the heads up. --- --- 20131118.9 Update for Lua 5.3... it seems that tostring(2/1) produces "2.0" instead of "2", --- and this caused some problems. --- --- 20131031.8 Unified the code for encode() and encode_pretty(); they had been stupidly separate, --- and had of course diverged (encode_pretty didn't get the fixes that encode got, so --- sometimes produced incorrect results; thanks to Mattie for the heads up). --- --- Handle encoding tables with non-positive numeric keys (unlikely, but possible). --- --- If a table has both numeric and string keys, or its numeric keys are inappropriate --- (such as being non-positive or infinite), the numeric keys are turned into --- string keys appropriate for a JSON object. So, as before, --- JSON:encode({ "one", "two", "three" }) --- produces the array --- ["one","two","three"] --- but now something with mixed key types like --- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" })) --- instead of throwing an error produces an object: --- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"} --- --- To maintain the prior throw-an-error semantics, set --- JSON.noKeyConversion = true --- --- 20131004.7 Release under a Creative Commons CC-BY license, which I should have done from day one, sorry. --- --- 20130120.6 Comment update: added a link to the specific page on my blog where this code can --- be found, so that folks who come across the code outside of my blog can find updates --- more easily. --- --- 20111207.5 Added support for the 'etc' arguments, for better error reporting. --- --- 20110731.4 More feedback from David Kolf on how to make the tests for Nan/Infinity system independent. --- --- 20110730.3 Incorporated feedback from David Kolf at http://lua-users.org/wiki/JsonModules: --- --- * When encoding lua for JSON, Sparse numeric arrays are now handled by --- spitting out full arrays, such that --- JSON:encode({"one", "two", [10] = "ten"}) --- returns --- ["one","two",null,null,null,null,null,null,null,"ten"] --- --- In 20100810.2 and earlier, only up to the first non-null value would have been retained. --- --- * When encoding lua for JSON, numeric value NaN gets spit out as null, and infinity as "1+e9999". --- Version 20100810.2 and earlier created invalid JSON in both cases. --- --- * Unicode surrogate pairs are now detected when decoding JSON. --- --- 20100810.2 added some checking to ensure that an invalid Unicode character couldn't leak in to the UTF-8 encoding --- --- 20100731.1 initial public release --- +return json