X-Git-Url: https://git.archive.openwrt.org/?p=project%2Fluci.git;a=blobdiff_plain;f=libs%2Fluci-lib-json%2Fluasrc%2Fjson.lua;fp=libs%2Fluci-lib-json%2Fluasrc%2Fjson.lua;h=8dbaf91836422dbfc1fbb90636f588227ae13cc0;hp=0000000000000000000000000000000000000000;hb=1bb4822dca6113f73e3bc89e2acf15935e6f8e92;hpb=9edd0e46c3f880727738ce8ca6ff1c8b85f99ef4

diff --git a/libs/luci-lib-json/luasrc/json.lua b/libs/luci-lib-json/luasrc/json.lua
new file mode 100644
index 000000000..8dbaf9183
--- /dev/null
+++ b/libs/luci-lib-json/luasrc/json.lua
@@ -0,0 +1,600 @@
+--[[
+LuCI - Lua Configuration Interface
+
+Copyright 2008 Steven Barth <steven@midlink.org>
+Copyright 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+
+Decoder:
+	Info:
+		null will be decoded to luci.json.null if first parameter of Decoder() is true
+
+	Example:
+		decoder = luci.json.Decoder()
+		luci.ltn12.pump.all(luci.ltn12.source.string("decodableJSON"), decoder:sink())
+		luci.util.dumptable(decoder:get())
+
+	Known issues:
+		does not support unicode conversion \uXXYY with XX != 00 will be ignored
+
+
+Encoder:
+	Info:
+		Accepts numbers, strings, nil, booleans as they are
+		Accepts luci.json.null as replacement for nil
+		Accepts full associative and full numerically indexed tables
+		Mixed tables will loose their associative values during conversion
+		Iterator functions will be encoded as an array of their return values
+		Non-iterator functions will probably corrupt the encoder
+
+	Example:
+		encoder = luci.json.Encoder(encodableData)
+		luci.ltn12.pump.all(encoder:source(), luci.ltn12.sink.file(io.open("someFile", w)))
+]]--
+
+local nixio     = require "nixio"
+local util      = require "luci.util"
+local table     = require "table"
+local string    = require "string"
+local coroutine = require "coroutine"
+
+local assert    = assert
+local tonumber  = tonumber
+local tostring  = tostring
+local error     = error
+local type	    = type
+local pairs	    = pairs
+local ipairs    = ipairs
+local next      = next
+local pcall		= pcall
+
+local band      = nixio.bit.band
+local bor       = nixio.bit.bor
+local rshift    = nixio.bit.rshift
+local char      = string.char
+
+local getmetatable = getmetatable
+
+--- LuCI JSON-Library
+-- @cstyle	instance
+module "luci.json"
+
+
+--- Directly decode a JSON string
+-- @param json JSON-String
+-- @return Lua object
+function decode(json, ...)
+	local a = ActiveDecoder(function() return nil end, ...)
+	a.chunk = json
+	local s, obj = pcall(a.get, a)
+	return s and obj or nil
+end
+
+
+--- Direcly encode a Lua object into a JSON string.
+-- @param obj Lua Object
+-- @return JSON string
+function encode(obj, ...)
+	local out = {}
+	local e = Encoder(obj, 1, ...):source()
+	local chnk, err
+	repeat
+		chnk, err = e()
+		out[#out+1] = chnk
+	until not chnk
+	return not err and table.concat(out) or nil
+end
+
+
+--- Null replacement function
+-- @return null
+function null()
+	return null
+end
+
+--- Create a new JSON-Encoder.
+-- @class	function
+-- @name	Encoder
+-- @param data			Lua-Object to be encoded.
+-- @param buffersize	Blocksize of returned data source.
+-- @param fastescape	Use non-standard escaping (don't escape control chars)
+-- @return JSON-Encoder
+Encoder = util.class()
+
+function Encoder.__init__(self, data, buffersize, fastescape)
+	self.data = data
+	self.buffersize = buffersize or 512
+	self.buffer = ""
+	self.fastescape = fastescape
+
+	getmetatable(self).__call = Encoder.source
+end
+
+--- Create an LTN12 source providing the encoded JSON-Data.
+-- @return LTN12 source
+function Encoder.source(self)
+	local source = coroutine.create(self.dispatch)
+	return function()
+		local res, data = coroutine.resume(source, self, self.data, true)
+		if res then
+			return data
+		else
+			return nil, data
+		end
+	end
+end
+
+function Encoder.dispatch(self, data, start)
+	local parser = self.parsers[type(data)]
+
+	parser(self, data)
+
+	if start then
+		if #self.buffer > 0 then
+			coroutine.yield(self.buffer)
+		end
+
+		coroutine.yield()
+	end
+end
+
+function Encoder.put(self, chunk)
+	if self.buffersize < 2 then
+		coroutine.yield(chunk)
+	else
+		if #self.buffer + #chunk > self.buffersize then
+			local written = 0
+			local fbuffer = self.buffersize - #self.buffer
+
+			coroutine.yield(self.buffer .. chunk:sub(written + 1, fbuffer))
+			written = fbuffer
+
+			while #chunk - written > self.buffersize do
+				fbuffer = written + self.buffersize
+				coroutine.yield(chunk:sub(written + 1, fbuffer))
+				written = fbuffer
+			end
+
+			self.buffer = chunk:sub(written + 1)
+		else
+			self.buffer = self.buffer .. chunk
+		end
+	end
+end
+
+function Encoder.parse_nil(self)
+	self:put("null")
+end
+
+function Encoder.parse_bool(self, obj)
+	self:put(obj and "true" or "false")
+end
+
+function Encoder.parse_number(self, obj)
+	self:put(tostring(obj))
+end
+
+function Encoder.parse_string(self, obj)
+	if self.fastescape then
+		self:put('"' .. obj:gsub('\\', '\\\\'):gsub('"', '\\"') .. '"')
+	else
+		self:put('"' ..
+			obj:gsub('[%c\\"]',
+				function(char)
+					return '\\u00%02x' % char:byte()
+				end
+			)
+		.. '"')
+	end
+end
+
+function Encoder.parse_iter(self, obj)
+	if obj == null then
+		return self:put("null")
+	end
+
+	if type(obj) == "table" and (#obj == 0 and next(obj)) then
+		self:put("{")
+		local first = true
+
+		for key, entry in pairs(obj) do
+			first = first or self:put(",")
+			first = first and false
+			self:parse_string(tostring(key))
+			self:put(":")
+			self:dispatch(entry)
+		end
+
+		self:put("}")
+	else
+		self:put("[")
+		local first = true
+
+		if type(obj) == "table" then
+			for i=1, #obj do
+				first = first or self:put(",")
+				first = first and nil
+				self:dispatch(obj[i])
+			end
+		else
+			for entry in obj do
+				first = first or self:put(",")
+				first = first and nil
+				self:dispatch(entry)
+			end
+		end
+
+		self:put("]")
+	end
+end
+
+Encoder.parsers = {
+	['nil']      = Encoder.parse_nil,
+	['table']    = Encoder.parse_iter,
+	['number']   = Encoder.parse_number,
+	['string']   = Encoder.parse_string,
+	['boolean']  = Encoder.parse_bool,
+	['function'] = Encoder.parse_iter
+}
+
+
+--- Create a new JSON-Decoder.
+-- @class	function
+-- @name	Decoder
+-- @param customnull Use luci.json.null instead of nil for decoding null
+-- @return JSON-Decoder
+Decoder = util.class()
+
+function Decoder.__init__(self, customnull)
+	self.cnull = customnull
+	getmetatable(self).__call = Decoder.sink
+end
+
+--- Create an LTN12 sink from the decoder object which accepts the JSON-Data.
+-- @return LTN12 sink
+function Decoder.sink(self)
+	local sink = coroutine.create(self.dispatch)
+	return function(...)
+		return coroutine.resume(sink, self, ...)
+	end
+end
+
+
+--- Get the decoded data packets after the rawdata has been sent to the sink.
+-- @return Decoded data
+function Decoder.get(self)
+	return self.data
+end
+
+function Decoder.dispatch(self, chunk, src_err, strict)
+	local robject, object
+	local oset = false
+
+	while chunk do
+		while chunk and #chunk < 1 do
+			chunk = self:fetch()
+		end
+
+		assert(not strict or chunk, "Unexpected EOS")
+		if not chunk then break end
+
+		local char   = chunk:sub(1, 1)
+		local parser = self.parsers[char]
+		 or (char:match("%s")     and self.parse_space)
+		 or (char:match("[0-9-]") and self.parse_number)
+		 or error("Unexpected char '%s'" % char)
+
+		chunk, robject = parser(self, chunk)
+
+		if parser ~= self.parse_space then
+			assert(not oset, "Scope violation: Too many objects")
+			object = robject
+			oset = true
+
+			if strict then
+				return chunk, object
+			end
+		end
+	end
+
+	assert(not src_err, src_err)
+	assert(oset, "Unexpected EOS")
+
+	self.data = object
+end
+
+
+function Decoder.fetch(self)
+	local tself, chunk, src_err = coroutine.yield()
+	assert(chunk or not src_err, src_err)
+	return chunk
+end
+
+
+function Decoder.fetch_atleast(self, chunk, bytes)
+	while #chunk < bytes do
+		local nchunk = self:fetch()
+		assert(nchunk, "Unexpected EOS")
+		chunk = chunk .. nchunk
+	end
+
+	return chunk
+end
+
+
+function Decoder.fetch_until(self, chunk, pattern)
+	local start = chunk:find(pattern)
+
+	while not start do
+		local nchunk = self:fetch()
+		assert(nchunk, "Unexpected EOS")
+		chunk = chunk .. nchunk
+		start = chunk:find(pattern)
+	end
+
+	return chunk, start
+end
+
+
+function Decoder.parse_space(self, chunk)
+	local start = chunk:find("[^%s]")
+
+	while not start do
+		chunk = self:fetch()
+		if not chunk then
+			return nil
+		end
+		start = chunk:find("[^%s]")
+	end
+
+	return chunk:sub(start)
+end
+
+
+function Decoder.parse_literal(self, chunk, literal, value)
+	chunk = self:fetch_atleast(chunk, #literal)
+	assert(chunk:sub(1, #literal) == literal, "Invalid character sequence")
+	return chunk:sub(#literal + 1), value
+end
+
+
+function Decoder.parse_null(self, chunk)
+	return self:parse_literal(chunk, "null", self.cnull and null)
+end
+
+
+function Decoder.parse_true(self, chunk)
+	return self:parse_literal(chunk, "true", true)
+end
+
+
+function Decoder.parse_false(self, chunk)
+	return self:parse_literal(chunk, "false", false)
+end
+
+
+function Decoder.parse_number(self, chunk)
+	local chunk, start = self:fetch_until(chunk, "[^0-9eE.+-]")
+	local number = tonumber(chunk:sub(1, start - 1))
+	assert(number, "Invalid number specification")
+	return chunk:sub(start), number
+end
+
+
+function Decoder.parse_string(self, chunk)
+	local str = ""
+	local object = nil
+	assert(chunk:sub(1, 1) == '"', 'Expected "')
+	chunk = chunk:sub(2)
+
+	while true do
+		local spos = chunk:find('[\\"]')
+		if spos then
+			str = str .. chunk:sub(1, spos - 1)
+
+			local char = chunk:sub(spos, spos)
+			if char == '"' then				-- String end
+				chunk = chunk:sub(spos + 1)
+				break
+			elseif char == "\\" then 		-- Escape sequence
+				chunk, object = self:parse_escape(chunk:sub(spos))
+				str = str .. object
+			end
+		else
+			str = str .. chunk
+			chunk = self:fetch()
+			assert(chunk, "Unexpected EOS while parsing a string")
+		end
+	end
+
+	return chunk, str
+end
+
+
+function Decoder.utf8_encode(self, s1, s2)
+	local n = s1 * 256 + s2
+
+	if n >= 0 and n <= 0x7F then
+		return char(n)
+	elseif n >= 0 and n <= 0x7FF then
+		return char(
+			bor(band(rshift(n,  6), 0x1F), 0xC0),
+			bor(band(n,             0x3F), 0x80)
+		)
+	elseif n >= 0 and n <= 0xFFFF then
+		return char(
+			bor(band(rshift(n, 12), 0x0F), 0xE0),
+			bor(band(rshift(n,  6), 0x3F), 0x80),
+			bor(band(n,             0x3F), 0x80)
+		)
+	elseif n >= 0 and n <= 0x10FFFF then
+		return char(
+			bor(band(rshift(n, 18), 0x07), 0xF0),
+			bor(band(rshift(n, 12), 0x3F), 0x80),
+			bor(band(rshift(n,  6), 0x3F), 0x80),
+			bor(band(n,             0x3F), 0x80)
+		)
+	else
+		return "?"
+	end
+end
+
+
+function Decoder.parse_escape(self, chunk)
+	local str = ""
+	chunk = self:fetch_atleast(chunk:sub(2), 1)
+	local char = chunk:sub(1, 1)
+	chunk = chunk:sub(2)
+
+	if char == '"' then
+		return chunk, '"'
+	elseif char == "\\" then
+		return chunk, "\\"
+	elseif char == "u" then
+		chunk = self:fetch_atleast(chunk, 4)
+		local s1, s2 = chunk:sub(1, 2), chunk:sub(3, 4)
+		s1, s2 = tonumber(s1, 16), tonumber(s2, 16)
+		assert(s1 and s2, "Invalid Unicode character")
+
+		return chunk:sub(5), self:utf8_encode(s1, s2)
+	elseif char == "/" then
+		return chunk, "/"
+	elseif char == "b" then
+		return chunk, "\b"
+	elseif char == "f" then
+		return chunk, "\f"
+	elseif char == "n" then
+		return chunk, "\n"
+	elseif char == "r" then
+		return chunk, "\r"
+	elseif char == "t" then
+		return chunk, "\t"
+	else
+		error("Unexpected escaping sequence '\\%s'" % char)
+	end
+end
+
+
+function Decoder.parse_array(self, chunk)
+	chunk = chunk:sub(2)
+	local array = {}
+	local nextp = 1
+
+	local chunk, object = self:parse_delimiter(chunk, "%]")
+
+	if object then
+		return chunk, array
+	end
+
+	repeat
+		chunk, object = self:dispatch(chunk, nil, true)
+		table.insert(array, nextp, object)
+		nextp = nextp + 1
+
+		chunk, object = self:parse_delimiter(chunk, ",%]")
+		assert(object, "Delimiter expected")
+	until object == "]"
+
+	return chunk, array
+end
+
+
+function Decoder.parse_object(self, chunk)
+	chunk = chunk:sub(2)
+	local array = {}
+	local name
+
+	local chunk, object = self:parse_delimiter(chunk, "}")
+
+	if object then
+		return chunk, array
+	end
+
+	repeat
+		chunk = self:parse_space(chunk)
+		assert(chunk, "Unexpected EOS")
+
+		chunk, name   = self:parse_string(chunk)
+
+		chunk, object = self:parse_delimiter(chunk, ":")
+		assert(object, "Separator expected")
+
+		chunk, object = self:dispatch(chunk, nil, true)
+		array[name] = object
+
+		chunk, object = self:parse_delimiter(chunk, ",}")
+		assert(object, "Delimiter expected")
+	until object == "}"
+
+	return chunk, array
+end
+
+
+function Decoder.parse_delimiter(self, chunk, delimiter)
+	while true do
+		chunk = self:fetch_atleast(chunk, 1)
+		local char = chunk:sub(1, 1)
+		if char:match("%s") then
+			chunk = self:parse_space(chunk)
+			assert(chunk, "Unexpected EOS")
+		elseif char:match("[%s]" % delimiter) then
+			return chunk:sub(2), char
+		else
+			return chunk, nil
+		end
+	end
+end
+
+
+Decoder.parsers = {
+	['"'] = Decoder.parse_string,
+	['t'] = Decoder.parse_true,
+	['f'] = Decoder.parse_false,
+	['n'] = Decoder.parse_null,
+	['['] = Decoder.parse_array,
+	['{'] = Decoder.parse_object
+}
+
+
+--- Create a new Active JSON-Decoder.
+-- @class	function
+-- @name	ActiveDecoder
+-- @param   customnull	Use luci.json.null instead of nil for decoding null
+-- @return  Active JSON-Decoder
+ActiveDecoder = util.class(Decoder)
+
+function ActiveDecoder.__init__(self, source, customnull)
+	Decoder.__init__(self, customnull)
+	self.source = source
+	self.chunk = nil
+	getmetatable(self).__call = self.get
+end
+
+
+--- Fetches one JSON-object from given source
+-- @return Decoded object
+function ActiveDecoder.get(self)
+	local chunk, src_err, object
+	if not self.chunk then
+		chunk, src_err = self.source()
+	else
+		chunk = self.chunk
+	end
+
+	self.chunk, object = self:dispatch(chunk, src_err, true)
+	return object
+end
+
+
+function ActiveDecoder.fetch(self)
+	local chunk, src_err = self.source()
+	assert(chunk or not src_err, src_err)
+	return chunk
+end