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util/json.lua @ 4430:607de4c95129
net.xmppserver_listener: Set default interface to '*' (fixes traceback) (thanks Zash)
author | Matthew Wild <mwild1@gmail.com> |
---|---|
date | Mon, 28 Nov 2011 14:27:52 +0000 |
parent | 4404:5356664ef9d4 |
child | 4474:b08a46cf06e6 |
rev | line source |
---|---|
3979 | 1 |
2 local type = type; | |
3 local t_insert, t_concat, t_remove = table.insert, table.concat, table.remove; | |
4 local s_char = string.char; | |
5 local tostring, tonumber = tostring, tonumber; | |
6 local pairs, ipairs = pairs, ipairs; | |
7 local next = next; | |
8 local error = error; | |
9 local newproxy, getmetatable = newproxy, getmetatable; | |
10 local print = print; | |
11 | |
12 --module("json") | |
13 local json = {}; | |
14 | |
15 local null = newproxy and newproxy(true) or {}; | |
16 if getmetatable and getmetatable(null) then | |
17 getmetatable(null).__tostring = function() return "null"; end; | |
18 end | |
19 json.null = null; | |
20 | |
21 local escapes = { | |
22 ["\""] = "\\\"", ["\\"] = "\\\\", ["\b"] = "\\b", | |
23 ["\f"] = "\\f", ["\n"] = "\\n", ["\r"] = "\\r", ["\t"] = "\\t"}; | |
24 local unescapes = { | |
25 ["\""] = "\"", ["\\"] = "\\", ["/"] = "/", | |
26 b = "\b", f = "\f", n = "\n", r = "\r", t = "\t"}; | |
27 for i=0,31 do | |
28 local ch = s_char(i); | |
29 if not escapes[ch] then escapes[ch] = ("\\u%.4X"):format(i); end | |
30 end | |
31 | |
32 local valid_types = { | |
33 number = true, | |
34 string = true, | |
35 table = true, | |
36 boolean = true | |
37 }; | |
38 local special_keys = { | |
39 __array = true; | |
40 __hash = true; | |
41 }; | |
42 | |
43 local simplesave, tablesave, arraysave, stringsave; | |
44 | |
45 function stringsave(o, buffer) | |
46 -- FIXME do proper utf-8 and binary data detection | |
47 t_insert(buffer, "\""..(o:gsub(".", escapes)).."\""); | |
48 end | |
49 | |
50 function arraysave(o, buffer) | |
51 t_insert(buffer, "["); | |
52 if next(o) then | |
53 for i,v in ipairs(o) do | |
54 simplesave(v, buffer); | |
55 t_insert(buffer, ","); | |
56 end | |
57 t_remove(buffer); | |
58 end | |
59 t_insert(buffer, "]"); | |
60 end | |
61 | |
62 function tablesave(o, buffer) | |
63 local __array = {}; | |
64 local __hash = {}; | |
65 local hash = {}; | |
66 for i,v in ipairs(o) do | |
67 __array[i] = v; | |
68 end | |
69 for k,v in pairs(o) do | |
70 local ktype, vtype = type(k), type(v); | |
71 if valid_types[vtype] or v == null then | |
72 if ktype == "string" and not special_keys[k] then | |
73 hash[k] = v; | |
74 elseif (valid_types[ktype] or k == null) and __array[k] == nil then | |
75 __hash[k] = v; | |
76 end | |
77 end | |
78 end | |
79 if next(__hash) ~= nil or next(hash) ~= nil or next(__array) == nil then | |
80 t_insert(buffer, "{"); | |
81 local mark = #buffer; | |
82 for k,v in pairs(hash) do | |
83 stringsave(k, buffer); | |
84 t_insert(buffer, ":"); | |
85 simplesave(v, buffer); | |
86 t_insert(buffer, ","); | |
87 end | |
88 if next(__hash) ~= nil then | |
89 t_insert(buffer, "\"__hash\":["); | |
90 for k,v in pairs(__hash) do | |
91 simplesave(k, buffer); | |
92 t_insert(buffer, ","); | |
93 simplesave(v, buffer); | |
94 t_insert(buffer, ","); | |
95 end | |
96 t_remove(buffer); | |
97 t_insert(buffer, "]"); | |
98 t_insert(buffer, ","); | |
99 end | |
100 if next(__array) then | |
101 t_insert(buffer, "\"__array\":"); | |
102 arraysave(__array, buffer); | |
103 t_insert(buffer, ","); | |
104 end | |
105 if mark ~= #buffer then t_remove(buffer); end | |
106 t_insert(buffer, "}"); | |
107 else | |
108 arraysave(__array, buffer); | |
109 end | |
110 end | |
111 | |
112 function simplesave(o, buffer) | |
113 local t = type(o); | |
114 if t == "number" then | |
115 t_insert(buffer, tostring(o)); | |
116 elseif t == "string" then | |
117 stringsave(o, buffer); | |
118 elseif t == "table" then | |
119 tablesave(o, buffer); | |
120 elseif t == "boolean" then | |
121 t_insert(buffer, (o and "true" or "false")); | |
122 else | |
123 t_insert(buffer, "null"); | |
124 end | |
125 end | |
126 | |
127 function json.encode(obj) | |
128 local t = {}; | |
129 simplesave(obj, t); | |
130 return t_concat(t); | |
131 end | |
132 | |
133 ----------------------------------- | |
134 | |
135 | |
136 function json.decode(json) | |
4284
20979f124ad9
util.json: Fixed handling of truncated JSON.
Waqas Hussain <waqas20@gmail.com>
parents:
4147
diff
changeset
|
137 json = json.." "; -- appending a space ensures valid json wouldn't touch EOF |
3979 | 138 local pos = 1; |
139 local current = {}; | |
140 local stack = {}; | |
141 local ch, peek; | |
142 local function next() | |
143 ch = json:sub(pos, pos); | |
4284
20979f124ad9
util.json: Fixed handling of truncated JSON.
Waqas Hussain <waqas20@gmail.com>
parents:
4147
diff
changeset
|
144 if ch == "" then error("Unexpected EOF"); end |
3979 | 145 pos = pos+1; |
146 peek = json:sub(pos, pos); | |
147 return ch; | |
148 end | |
149 | |
150 local function skipwhitespace() | |
151 while ch and (ch == "\r" or ch == "\n" or ch == "\t" or ch == " ") do | |
152 next(); | |
153 end | |
154 end | |
155 local function skiplinecomment() | |
156 repeat next(); until not(ch) or ch == "\r" or ch == "\n"; | |
157 skipwhitespace(); | |
158 end | |
159 local function skipstarcomment() | |
160 next(); next(); -- skip '/', '*' | |
161 while peek and ch ~= "*" and peek ~= "/" do next(); end | |
162 if not peek then error("eof in star comment") end | |
163 next(); next(); -- skip '*', '/' | |
164 skipwhitespace(); | |
165 end | |
166 local function skipstuff() | |
167 while true do | |
168 skipwhitespace(); | |
169 if ch == "/" and peek == "*" then | |
170 skipstarcomment(); | |
4404
5356664ef9d4
util.json: Fix for single-line comments (thanks Norbert Kiesel)
Matthew Wild <mwild1@gmail.com>
parents:
4284
diff
changeset
|
171 elseif ch == "/" and peek == "/" then |
3979 | 172 skiplinecomment(); |
173 else | |
174 return; | |
175 end | |
176 end | |
177 end | |
178 | |
179 local readvalue; | |
180 local function readarray() | |
181 local t = {}; | |
182 next(); -- skip '[' | |
183 skipstuff(); | |
184 if ch == "]" then next(); return t; end | |
185 t_insert(t, readvalue()); | |
186 while true do | |
187 skipstuff(); | |
188 if ch == "]" then next(); return t; end | |
189 if not ch then error("eof while reading array"); | |
190 elseif ch == "," then next(); | |
191 elseif ch then error("unexpected character in array, comma expected"); end | |
192 if not ch then error("eof while reading array"); end | |
193 t_insert(t, readvalue()); | |
194 end | |
195 end | |
196 | |
197 local function checkandskip(c) | |
198 local x = ch or "eof"; | |
199 if x ~= c then error("unexpected "..x..", '"..c.."' expected"); end | |
200 next(); | |
201 end | |
202 local function readliteral(lit, val) | |
203 for c in lit:gmatch(".") do | |
204 checkandskip(c); | |
205 end | |
206 return val; | |
207 end | |
208 local function readstring() | |
209 local s = ""; | |
210 checkandskip("\""); | |
211 while ch do | |
212 while ch and ch ~= "\\" and ch ~= "\"" do | |
213 s = s..ch; next(); | |
214 end | |
215 if ch == "\\" then | |
216 next(); | |
217 if unescapes[ch] then | |
218 s = s..unescapes[ch]; | |
219 next(); | |
220 elseif ch == "u" then | |
221 local seq = ""; | |
222 for i=1,4 do | |
223 next(); | |
224 if not ch then error("unexpected eof in string"); end | |
225 if not ch:match("[0-9a-fA-F]") then error("invalid unicode escape sequence in string"); end | |
226 seq = seq..ch; | |
227 end | |
228 s = s..s.char(tonumber(seq, 16)); -- FIXME do proper utf-8 | |
229 next(); | |
230 else error("invalid escape sequence in string"); end | |
231 end | |
232 if ch == "\"" then | |
233 next(); | |
234 return s; | |
235 end | |
236 end | |
237 error("eof while reading string"); | |
238 end | |
239 local function readnumber() | |
240 local s = ""; | |
241 if ch == "-" then | |
242 s = s..ch; next(); | |
243 if not ch:match("[0-9]") then error("number format error"); end | |
244 end | |
245 if ch == "0" then | |
246 s = s..ch; next(); | |
247 if ch:match("[0-9]") then error("number format error"); end | |
248 else | |
249 while ch and ch:match("[0-9]") do | |
250 s = s..ch; next(); | |
251 end | |
252 end | |
253 if ch == "." then | |
254 s = s..ch; next(); | |
255 if not ch:match("[0-9]") then error("number format error"); end | |
256 while ch and ch:match("[0-9]") do | |
257 s = s..ch; next(); | |
258 end | |
259 if ch == "e" or ch == "E" then | |
260 s = s..ch; next(); | |
261 if ch == "+" or ch == "-" then | |
262 s = s..ch; next(); | |
263 if not ch:match("[0-9]") then error("number format error"); end | |
264 while ch and ch:match("[0-9]") do | |
265 s = s..ch; next(); | |
266 end | |
267 end | |
268 end | |
269 end | |
270 return tonumber(s); | |
271 end | |
272 local function readmember(t) | |
4147
7f119ebcf55f
util.json: Fixed a parse error caused by unexpected whitespace.
Waqas Hussain <waqas20@gmail.com>
parents:
3979
diff
changeset
|
273 skipstuff(); |
3979 | 274 local k = readstring(); |
4147
7f119ebcf55f
util.json: Fixed a parse error caused by unexpected whitespace.
Waqas Hussain <waqas20@gmail.com>
parents:
3979
diff
changeset
|
275 skipstuff(); |
3979 | 276 checkandskip(":"); |
277 t[k] = readvalue(); | |
278 end | |
279 local function fixobject(obj) | |
280 local __array = obj.__array; | |
281 if __array then | |
282 obj.__array = nil; | |
283 for i,v in ipairs(__array) do | |
284 t_insert(obj, v); | |
285 end | |
286 end | |
287 local __hash = obj.__hash; | |
288 if __hash then | |
289 obj.__hash = nil; | |
290 local k; | |
291 for i,v in ipairs(__hash) do | |
292 if k ~= nil then | |
293 obj[k] = v; k = nil; | |
294 else | |
295 k = v; | |
296 end | |
297 end | |
298 end | |
299 return obj; | |
300 end | |
301 local function readobject() | |
302 local t = {}; | |
303 next(); -- skip '{' | |
304 skipstuff(); | |
305 if ch == "}" then next(); return t; end | |
306 if not ch then error("eof while reading object"); end | |
307 readmember(t); | |
308 while true do | |
309 skipstuff(); | |
310 if ch == "}" then next(); return fixobject(t); end | |
311 if not ch then error("eof while reading object"); | |
312 elseif ch == "," then next(); | |
313 elseif ch then error("unexpected character in object, comma expected"); end | |
314 if not ch then error("eof while reading object"); end | |
315 readmember(t); | |
316 end | |
317 end | |
318 | |
319 function readvalue() | |
320 skipstuff(); | |
321 while ch do | |
322 if ch == "{" then | |
323 return readobject(); | |
324 elseif ch == "[" then | |
325 return readarray(); | |
326 elseif ch == "\"" then | |
327 return readstring(); | |
328 elseif ch:match("[%-0-9%.]") then | |
329 return readnumber(); | |
330 elseif ch == "n" then | |
331 return readliteral("null", null); | |
332 elseif ch == "t" then | |
333 return readliteral("true", true); | |
334 elseif ch == "f" then | |
335 return readliteral("false", false); | |
336 else | |
337 error("invalid character at value start: "..ch); | |
338 end | |
339 end | |
340 error("eof while reading value"); | |
341 end | |
342 next(); | |
343 return readvalue(); | |
344 end | |
345 | |
346 function json.test(object) | |
347 local encoded = json.encode(object); | |
348 local decoded = json.decode(encoded); | |
349 local recoded = json.encode(decoded); | |
350 if encoded ~= recoded then | |
351 print("FAILED"); | |
352 print("encoded:", encoded); | |
353 print("recoded:", recoded); | |
354 else | |
355 print(encoded); | |
356 end | |
357 return encoded == recoded; | |
358 end | |
359 | |
360 return json; |