--[[
+LuCI - Lua Configuration Interface
- JSON Encoder and Parser for Lua 5.1
-
- Copyright � 2007 Shaun Brown (http://www.chipmunkav.com).
- All Rights Reserved.
-
- Permission is hereby granted, free of charge, to any person
- obtaining a copy of this 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:
-
- The above copyright notice and this permission notice shall be
- included in all copies or substantial portions of the Software.
- If you find this software useful please give www.chipmunkav.com a mention.
-
- 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.
-
- Usage:
-
- -- Lua script:
- local t = {
- ["name1"] = "value1",
- ["name2"] = {1, false, true, 23.54, "a \021 string"},
- name3 = Json.Null()
- }
-
- local json = Json.Encode (t)
- print (json)
- --> {"name1":"value1","name3":null,"name2":[1,false,true,23.54,"a \u0015 string"]}
-
- local t = Json.Decode(json)
- print(t.name2[4])
- --> 23.54
-
- Notes:
- 1) Encodable Lua types: string, number, boolean, table, nil
- 2) Use Json.Null() to insert a null value into a Json object
- 3) All control chars are encoded to \uXXXX format eg "\021" encodes to "\u0015"
- 4) All Json \uXXXX chars are decoded to chars (0-255 byte range only)
- 5) Json single line // and /* */ block comments are discarded during decoding
- 6) Numerically indexed Lua arrays are encoded to Json Lists eg [1,2,3]
- 7) Lua dictionary tables are converted to Json objects eg {"one":1,"two":2}
- 8) Json nulls are decoded to Lua nil and treated by Lua in the normal way
-
---]]
-
-local string = string
-local math = math
-local table = table
-local error = error
-local tonumber = tonumber
-local tostring = tostring
-local type = type
-local setmetatable = setmetatable
-local pairs = pairs
-local ipairs = ipairs
-local assert = assert
-local Chipmunk = Chipmunk
-
-module("luci.json")
-
-local StringBuilder = {
- buffer = {}
-}
-
-function StringBuilder:New()
- local o = {}
- setmetatable(o, self)
- self.__index = self
- o.buffer = {}
- return o
-end
+Copyright 2008 Steven Barth <steven@midlink.org>
+Copyright 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
-function StringBuilder:Append(s)
- self.buffer[#self.buffer+1] = s
-end
+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
-function StringBuilder:ToString()
- return table.concat(self.buffer)
-end
+http://www.apache.org/licenses/LICENSE-2.0
-local JsonWriter = {
- backslashes = {
- ['\b'] = "\\b",
- ['\t'] = "\\t",
- ['\n'] = "\\n",
- ['\f'] = "\\f",
- ['\r'] = "\\r",
- ['"'] = "\\\"",
- ['\\'] = "\\\\",
- ['/'] = "\\/"
- }
-}
-
-function JsonWriter:New()
- local o = {}
- o.writer = StringBuilder:New()
- setmetatable(o, self)
- self.__index = self
- return o
-end
+$Id$
+]]--
-function JsonWriter:Append(s)
- self.writer:Append(s)
-end
+local util = require "luci.util"
+local ltn12 = require "luci.ltn12"
+local table = require "table"
+local coroutine = require "coroutine"
+
+local assert = assert
+local tonumber = tonumber
+local error = error
-function JsonWriter:ToString()
- return self.writer:ToString()
+module "luci.json"
+
+--- Null replacement function
+-- @return null
+function null()
+ return null
end
-function JsonWriter:Write(o)
- local t = type(o)
- if t == "nil" then
- self:WriteNil()
- elseif t == "boolean" then
- self:WriteString(o)
- elseif t == "number" then
- self:WriteString(o)
- elseif t == "string" then
- self:ParseString(o)
- elseif t == "table" then
- self:WriteTable(o)
- elseif t == "function" then
- self:WriteFunction(o)
- elseif t == "thread" then
- self:WriteError(o)
- elseif t == "userdata" then
- self:WriteError(o)
+Decoder = util.class()
+
+--- Create an LTN12 sink from the decoder object
+-- @return LTN12 sink
+function Decoder.sink(self)
+ local sink = coroutine.create(self.dispatch)
+ return function(...)
+ return coroutine.resume(sink, self, ...)
end
end
-function JsonWriter:WriteNil()
- self:Append("null")
-end
-function JsonWriter:WriteString(o)
- self:Append(tostring(o))
+--- Get the decoded data packets
+-- @return Decoded data
+function Decoder.get(self)
+ return self.data
end
-function JsonWriter:ParseString(s)
- self:Append('"')
- self:Append(string.gsub(s, "[%z%c\\\"/]", function(n)
- local c = self.backslashes[n]
- if c then return c end
- return string.format("\\u%.4X", string.byte(n))
- end))
- self:Append('"')
-end
-function JsonWriter:IsArray(t)
- local count = 0
- local isindex = function(k)
- if type(k) == "number" and k > 0 then
- if math.floor(k) == k then
- return true
- end
+function Decoder.dispatch(self, chunk, src_err, strict)
+ local robject, object
+
+ while chunk do
+ if #chunk < 1 then
+ chunk = self:fetch()
end
- return false
- end
- for k,v in pairs(t) do
- if not isindex(k) then
- return false, '{', '}'
- else
- count = math.max(count, k)
+
+ assert(not strict or chunk, "Unexpected EOS")
+ if not chunk then
+ break
end
- end
- return true, '[', ']', count
-end
-
-function JsonWriter:WriteTable(t)
- local ba, st, et, n = self:IsArray(t)
- self:Append(st)
- if ba then
- for i = 1, n do
- self:Write(t[i])
- if i < n then
- self:Append(',')
- end
+
+ local parser = nil
+ local char = chunk:sub(1, 1)
+
+ if char == '"' then
+ parser = self.parse_string
+ elseif char == 't' then
+ parser = self.parse_true
+ elseif char == 'f' then
+ parser = self.parse_false
+ elseif char == 'n' then
+ parser = self.parse_null
+ elseif char == '[' then
+ parser = self.parse_array
+ elseif char == '{' then
+ parser = self.parse_object
+ elseif char:match("%s") then
+ parser = self.parse_space
+ elseif char:match("[0-9-]") then
+ parser = self.parse_number
end
- else
- local first = true;
- for k, v in pairs(t) do
- if not first then
- self:Append(',')
+
+ if parser then
+ chunk, robject = parser(self, chunk)
+
+ if robject ~= nil then
+ assert(object == nil, "Scope violation: Too many objects")
+ object = robject
end
- first = false;
- self:ParseString(k)
- self:Append(':')
- self:Write(v)
+
+ if strict and object ~= nil then
+ return chunk, object
+ end
+ else
+ error("Unexpected char '%s'" % char)
end
end
- self:Append(et)
+
+ assert(not src_err, src_err)
+ assert(object ~= nil, "Unexpected EOS")
+
+ self.data = object
+ return chunk, object
end
-function JsonWriter:WriteError(o)
- error(string.format(
- "Encoding of %s unsupported",
- tostring(o)))
-end
-function JsonWriter:WriteFunction(o)
- if o == Null then
- self:WriteNil()
- else
- self:WriteError(o)
- end
+function Decoder.fetch(self)
+ local tself, chunk, src_err = coroutine.yield()
+ assert(chunk or not src_err, src_err)
+ return chunk
end
-local StringReader = {
- s = "",
- i = 0
-}
-
-function StringReader:New(s)
- local o = {}
- setmetatable(o, self)
- self.__index = self
- o.s = s or o.s
- return o
-end
-function StringReader:Peek()
- local i = self.i + 1
- if i <= #self.s then
- return string.sub(self.s, i, i)
+function Decoder.fetch_atleast(self, chunk, bytes)
+ while #chunk < bytes do
+ local nchunk = self:fetch()
+ assert(nchunk, "Unexpected EOS")
+ chunk = chunk .. nchunk
end
- return nil
+
+ return chunk
end
-function StringReader:Next()
- self.i = self.i+1
- if self.i <= #self.s then
- return string.sub(self.s, self.i, self.i)
- end
- return nil
-end
-function StringReader:All()
- return self.s
-end
-
-local JsonReader = {
- escapes = {
- ['t'] = '\t',
- ['n'] = '\n',
- ['f'] = '\f',
- ['r'] = '\r',
- ['b'] = '\b',
- }
-}
-
-function JsonReader:New(s)
- local o = {}
- o.reader = StringReader:New(s)
- setmetatable(o, self)
- self.__index = self
- return o;
-end
+function Decoder.fetch_until(self, chunk, pattern)
+ local start = chunk:find(pattern)
-function JsonReader:Read()
- self:SkipWhiteSpace()
- local peek = self:Peek()
- if peek == nil then
- error(string.format(
- "Nil string: '%s'",
- self:All()))
- elseif peek == '{' then
- return self:ReadObject()
- elseif peek == '[' then
- return self:ReadArray()
- elseif peek == '"' then
- return self:ReadString()
- elseif string.find(peek, "[%+%-%d]") then
- return self:ReadNumber()
- elseif peek == 't' then
- return self:ReadTrue()
- elseif peek == 'f' then
- return self:ReadFalse()
- elseif peek == 'n' then
- return self:ReadNull()
- elseif peek == '/' then
- self:ReadComment()
- return self:Read()
- else
- error(string.format(
- "Invalid input: '%s'",
- self:All()))
+ while not start do
+ local nchunk = self:fetch()
+ assert(nchunk, "Unexpected EOS")
+ chunk = chunk .. nchunk
+ start = chunk:find(pattern)
end
-end
-
-function JsonReader:ReadTrue()
- self:TestReservedWord{'t','r','u','e'}
- return true
-end
-function JsonReader:ReadFalse()
- self:TestReservedWord{'f','a','l','s','e'}
- return false
+ return chunk, start
end
-function JsonReader:ReadNull()
- self:TestReservedWord{'n','u','l','l'}
- return nil
-end
-function JsonReader:TestReservedWord(t)
- for i, v in ipairs(t) do
- if self:Next() ~= v then
- error(string.format(
- "Error reading '%s': %s",
- table.concat(t),
- self:All()))
+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 JsonReader:ReadNumber()
- local result = self:Next()
- local peek = self:Peek()
- while peek ~= nil and string.find(
- peek,
- "[%+%-%d%.eE]") do
- result = result .. self:Next()
- peek = self:Peek()
- end
- result = tonumber(result)
- if result == nil then
- error(string.format(
- "Invalid number: '%s'",
- result))
- else
- return result
- 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 JsonReader:ReadString()
- local result = ""
- assert(self:Next() == '"')
- while self:Peek() ~= '"' do
- local ch = self:Next()
- if ch == '\\' then
- ch = self:Next()
- if self.escapes[ch] then
- ch = self.escapes[ch]
- end
- end
- result = result .. ch
- end
- assert(self:Next() == '"')
- local fromunicode = function(m)
- return string.char(tonumber(m, 16))
- end
- return string.gsub(
- result,
- "u%x%x(%x%x)",
- fromunicode)
+
+function Decoder.parse_null(self, chunk)
+ return self:parse_literal(chunk, "null", null)
end
-function JsonReader:ReadComment()
- assert(self:Next() == '/')
- local second = self:Next()
- if second == '/' then
- self:ReadSingleLineComment()
- elseif second == '*' then
- self:ReadBlockComment()
- else
- error(string.format(
- "Invalid comment: %s",
- self:All()))
- end
+
+function Decoder.parse_true(self, chunk)
+ return self:parse_literal(chunk, "true", true)
end
-function JsonReader:ReadBlockComment()
- local done = false
- while not done do
- local ch = self:Next()
- if ch == '*' and self:Peek() == '/' then
- done = true
- end
- if not done and
- ch == '/' and
- self:Peek() == "*" then
- error(string.format(
- "Invalid comment: %s, '/*' illegal.",
- self:All()))
- end
- end
- self:Next()
+
+function Decoder.parse_false(self, chunk)
+ return self:parse_literal(chunk, "false", false)
end
-function JsonReader:ReadSingleLineComment()
- local ch = self:Next()
- while ch ~= '\r' and ch ~= '\n' do
- ch = self:Next()
- 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 JsonReader:ReadArray()
- local result = {}
- assert(self:Next() == '[')
- self:SkipWhiteSpace()
- local done = false
- if self:Peek() == ']' then
- done = true;
- end
- while not done do
- local item = self:Read()
- result[#result+1] = item
- self:SkipWhiteSpace()
- if self:Peek() == ']' then
- done = true
- end
- if not done then
- local ch = self:Next()
- if ch ~= ',' then
- error(string.format(
- "Invalid array: '%s' due to: '%s'",
- self:All(), ch))
+
+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
- assert(']' == self:Next())
- return result
-end
-function JsonReader:ReadObject()
- local result = {}
- assert(self:Next() == '{')
- self:SkipWhiteSpace()
- local done = false
- if self:Peek() == '}' then
- done = true
- end
- while not done do
- local key = self:Read()
- if type(key) ~= "string" then
- error(string.format(
- "Invalid non-string object key: %s",
- key))
- end
- self:SkipWhiteSpace()
- local ch = self:Next()
- if ch ~= ':' then
- error(string.format(
- "Invalid object: '%s' due to: '%s'",
- self:All(),
- ch))
- end
- self:SkipWhiteSpace()
- local val = self:Read()
- result[key] = val
- self:SkipWhiteSpace()
- if self:Peek() == '}' then
- done = true
- end
- if not done then
- ch = self:Next()
- if ch ~= ',' then
- error(string.format(
- "Invalid array: '%s' near: '%s'",
- self:All(),
- ch))
- end
- end
+ return chunk, str
+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 == "/" 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"
+ elseif char == "u" then
+ chunk = self:fetch_atleast(chunk, 4)
+ local s1, s2 = chunk:sub(1, 4):match("^([0-9a-fA-F][0-9a-fA-F])([0-9a-fA-F][0-9a-fA-F])$")
+ assert(s1 and s2, "Invalid Unicode character 'U+%s%s'" % {s1, s2})
+ s1, s2 = tonumber(s1, 16), tonumber(s2, 16)
+
+ -- ToDo: Unicode support
+ return chunk:sub(5), s1 == 0 and s2 or ""
+ else
+ error("Unexpected escaping sequence '\\%s'" % char)
end
- assert(self:Next() == "}")
- return result
end
-function JsonReader:SkipWhiteSpace()
- local p = self:Peek()
- while p ~= nil and string.find(p, "[%s/]") do
- if p == '/' then
- self:ReadComment()
- else
- self:Next()
- end
- p = self:Peek()
+
+function Decoder.parse_array(self, chunk)
+ chunk = chunk:sub(2)
+ local array = {}
+
+ local chunk, object = self:parse_delimiter(chunk, "%]")
+
+ if object then
+ return chunk, array
end
-end
+
+ repeat
+ chunk, object = self:dispatch(chunk, nil, true)
+ table.insert(array, object)
+
+ chunk, object = self:parse_delimiter(chunk, ",%]")
+ assert(object, "Delimiter expected")
+ until object == "]"
-function JsonReader:Peek()
- return self.reader:Peek()
+ return chunk, array
end
-function JsonReader:Next()
- return self.reader:Next()
-end
-function JsonReader:All()
- return self.reader:All()
-end
+function Decoder.parse_object(self, chunk)
+ chunk = chunk:sub(2)
+ local array = {}
+ local name
-function Encode(o)
- local writer = JsonWriter:New()
- writer:Write(o)
- return writer:ToString()
-end
+ local chunk, object = self:parse_delimiter(chunk, "}")
-function Decode(s)
- local reader = JsonReader:New(s)
- local object = reader:Read()
- reader:SkipWhiteSpace()
- assert(reader:Peek() == nil, "Invalid characters after JSON body")
- return object
-end
+ 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 == "}"
-function Null()
- return Null
+ 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
\ No newline at end of file
projects / oweals / luci.git / commitdiff