· 6 years ago · Jan 21, 2020, 08:16 AM
1--
2-- json.lua
3--
4-- Copyright (c) 2019 rxi
5--
6-- Permission is hereby granted, free of charge, to any person obtaining a copy of
7-- this software and associated documentation files (the "Software"), to deal in
8-- the Software without restriction, including without limitation the rights to
9-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
10-- of the Software, and to permit persons to whom the Software is furnished to do
11-- so, subject to the following conditions:
12--
13-- The above copyright notice and this permission notice shall be included in all
14-- copies or substantial portions of the Software.
15--
16-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22-- SOFTWARE.
23--
24
25local json = { _version = "0.1.2" }
26
27-------------------------------------------------------------------------------
28-- Encode
29-------------------------------------------------------------------------------
30
31local encode
32
33local escape_char_map = {
34 [ "\\" ] = "\\\\",
35 [ "\"" ] = "\\\"",
36 [ "\b" ] = "\\b",
37 [ "\f" ] = "\\f",
38 [ "\n" ] = "\\n",
39 [ "\r" ] = "\\r",
40 [ "\t" ] = "\\t",
41}
42
43local escape_char_map_inv = { [ "\\/" ] = "/" }
44for k, v in pairs(escape_char_map) do
45 escape_char_map_inv[v] = k
46end
47
48
49local function escape_char(c)
50 return escape_char_map[c] or string.format("\\u%04x", c:byte())
51end
52
53
54local function encode_nil(val)
55 return "null"
56end
57
58
59local function encode_table(val, stack)
60 local res = {}
61 stack = stack or {}
62
63 -- Circular reference?
64 if stack[val] then error("circular reference") end
65
66 stack[val] = true
67
68 if rawget(val, 1) ~= nil or next(val) == nil then
69 -- Treat as array -- check keys are valid and it is not sparse
70 local n = 0
71 for k in pairs(val) do
72 if type(k) ~= "number" then
73 error("invalid table: mixed or invalid key types")
74 end
75 n = n + 1
76 end
77 if n ~= #val then
78 error("invalid table: sparse array")
79 end
80 -- Encode
81 for i, v in ipairs(val) do
82 table.insert(res, encode(v, stack))
83 end
84 stack[val] = nil
85 return "[" .. table.concat(res, ",") .. "]"
86
87 else
88 -- Treat as an object
89 for k, v in pairs(val) do
90 if type(k) ~= "string" then
91 error("invalid table: mixed or invalid key types")
92 end
93 table.insert(res, encode(k, stack) .. ":" .. encode(v, stack))
94 end
95 stack[val] = nil
96 return "{" .. table.concat(res, ",") .. "}"
97 end
98end
99
100
101local function encode_string(val)
102 return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"'
103end
104
105
106local function encode_number(val)
107 -- Check for NaN, -inf and inf
108 if val ~= val or val <= -math.huge or val >= math.huge then
109 error("unexpected number value '" .. tostring(val) .. "'")
110 end
111 return string.format("%.14g", val)
112end
113
114
115local type_func_map = {
116 [ "nil" ] = encode_nil,
117 [ "table" ] = encode_table,
118 [ "string" ] = encode_string,
119 [ "number" ] = encode_number,
120 [ "boolean" ] = tostring,
121}
122
123
124encode = function(val, stack)
125 local t = type(val)
126 local f = type_func_map[t]
127 if f then
128 return f(val, stack)
129 end
130 error("unexpected type '" .. t .. "'")
131end
132
133
134function json.encode(val)
135 return ( encode(val) )
136end
137
138
139-------------------------------------------------------------------------------
140-- Decode
141-------------------------------------------------------------------------------
142
143local parse
144
145local function create_set(...)
146 local res = {}
147 for i = 1, select("#", ...) do
148 res[ select(i, ...) ] = true
149 end
150 return res
151end
152
153local space_chars = create_set(" ", "\t", "\r", "\n")
154local delim_chars = create_set(" ", "\t", "\r", "\n", "]", "}", ",")
155local escape_chars = create_set("\\", "/", '"', "b", "f", "n", "r", "t", "u")
156local literals = create_set("true", "false", "null")
157
158local literal_map = {
159 [ "true" ] = true,
160 [ "false" ] = false,
161 [ "null" ] = nil,
162}
163
164
165local function next_char(str, idx, set, negate)
166 for i = idx, #str do
167 if set[str:sub(i, i)] ~= negate then
168 return i
169 end
170 end
171 return #str + 1
172end
173
174
175local function decode_error(str, idx, msg)
176 local line_count = 1
177 local col_count = 1
178 for i = 1, idx - 1 do
179 col_count = col_count + 1
180 if str:sub(i, i) == "\n" then
181 line_count = line_count + 1
182 col_count = 1
183 end
184 end
185 error( string.format("%s at line %d col %d", msg, line_count, col_count) )
186end
187
188
189local function codepoint_to_utf8(n)
190 -- http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=iws-appendixa
191 local f = math.floor
192 if n <= 0x7f then
193 return string.char(n)
194 elseif n <= 0x7ff then
195 return string.char(f(n / 64) + 192, n % 64 + 128)
196 elseif n <= 0xffff then
197 return string.char(f(n / 4096) + 224, f(n % 4096 / 64) + 128, n % 64 + 128)
198 elseif n <= 0x10ffff then
199 return string.char(f(n / 262144) + 240, f(n % 262144 / 4096) + 128,
200 f(n % 4096 / 64) + 128, n % 64 + 128)
201 end
202 error( string.format("invalid unicode codepoint '%x'", n) )
203end
204
205
206local function parse_unicode_escape(s)
207 local n1 = tonumber( s:sub(3, 6), 16 )
208 local n2 = tonumber( s:sub(9, 12), 16 )
209 -- Surrogate pair?
210 if n2 then
211 return codepoint_to_utf8((n1 - 0xd800) * 0x400 + (n2 - 0xdc00) + 0x10000)
212 else
213 return codepoint_to_utf8(n1)
214 end
215end
216
217
218local function parse_string(str, i)
219 local has_unicode_escape = false
220 local has_surrogate_escape = false
221 local has_escape = false
222 local last
223 for j = i + 1, #str do
224 local x = str:byte(j)
225
226 if x < 32 then
227 decode_error(str, j, "control character in string")
228 end
229
230 if last == 92 then -- "\\" (escape char)
231 if x == 117 then -- "u" (unicode escape sequence)
232 local hex = str:sub(j + 1, j + 5)
233 if not hex:find("%x%x%x%x") then
234 decode_error(str, j, "invalid unicode escape in string")
235 end
236 if hex:find("^[dD][89aAbB]") then
237 has_surrogate_escape = true
238 else
239 has_unicode_escape = true
240 end
241 else
242 local c = string.char(x)
243 if not escape_chars[c] then
244 decode_error(str, j, "invalid escape char '" .. c .. "' in string")
245 end
246 has_escape = true
247 end
248 last = nil
249
250 elseif x == 34 then -- '"' (end of string)
251 local s = str:sub(i + 1, j - 1)
252 if has_surrogate_escape then
253 s = s:gsub("\\u[dD][89aAbB]..\\u....", parse_unicode_escape)
254 end
255 if has_unicode_escape then
256 s = s:gsub("\\u....", parse_unicode_escape)
257 end
258 if has_escape then
259 s = s:gsub("\\.", escape_char_map_inv)
260 end
261 return s, j + 1
262
263 else
264 last = x
265 end
266 end
267 decode_error(str, i, "expected closing quote for string")
268end
269
270
271local function parse_number(str, i)
272 local x = next_char(str, i, delim_chars)
273 local s = str:sub(i, x - 1)
274 local n = tonumber(s)
275 if not n then
276 decode_error(str, i, "invalid number '" .. s .. "'")
277 end
278 return n, x
279end
280
281
282local function parse_literal(str, i)
283 local x = next_char(str, i, delim_chars)
284 local word = str:sub(i, x - 1)
285 if not literals[word] then
286 decode_error(str, i, "invalid literal '" .. word .. "'")
287 end
288 return literal_map[word], x
289end
290
291
292local function parse_array(str, i)
293 local res = {}
294 local n = 1
295 i = i + 1
296 while 1 do
297 local x
298 i = next_char(str, i, space_chars, true)
299 -- Empty / end of array?
300 if str:sub(i, i) == "]" then
301 i = i + 1
302 break
303 end
304 -- Read token
305 x, i = parse(str, i)
306 res[n] = x
307 n = n + 1
308 -- Next token
309 i = next_char(str, i, space_chars, true)
310 local chr = str:sub(i, i)
311 i = i + 1
312 if chr == "]" then break end
313 if chr ~= "," then decode_error(str, i, "expected ']' or ','") end
314 end
315 return res, i
316end
317
318
319local function parse_object(str, i)
320 local res = {}
321 i = i + 1
322 while 1 do
323 local key, val
324 i = next_char(str, i, space_chars, true)
325 -- Empty / end of object?
326 if str:sub(i, i) == "}" then
327 i = i + 1
328 break
329 end
330 -- Read key
331 if str:sub(i, i) ~= '"' then
332 decode_error(str, i, "expected string for key")
333 end
334 key, i = parse(str, i)
335 -- Read ':' delimiter
336 i = next_char(str, i, space_chars, true)
337 if str:sub(i, i) ~= ":" then
338 decode_error(str, i, "expected ':' after key")
339 end
340 i = next_char(str, i + 1, space_chars, true)
341 -- Read value
342 val, i = parse(str, i)
343 -- Set
344 res[key] = val
345 -- Next token
346 i = next_char(str, i, space_chars, true)
347 local chr = str:sub(i, i)
348 i = i + 1
349 if chr == "}" then break end
350 if chr ~= "," then decode_error(str, i, "expected '}' or ','") end
351 end
352 return res, i
353end
354
355
356local char_func_map = {
357 [ '"' ] = parse_string,
358 [ "0" ] = parse_number,
359 [ "1" ] = parse_number,
360 [ "2" ] = parse_number,
361 [ "3" ] = parse_number,
362 [ "4" ] = parse_number,
363 [ "5" ] = parse_number,
364 [ "6" ] = parse_number,
365 [ "7" ] = parse_number,
366 [ "8" ] = parse_number,
367 [ "9" ] = parse_number,
368 [ "-" ] = parse_number,
369 [ "t" ] = parse_literal,
370 [ "f" ] = parse_literal,
371 [ "n" ] = parse_literal,
372 [ "[" ] = parse_array,
373 [ "{" ] = parse_object,
374}
375
376
377parse = function(str, idx)
378 local chr = str:sub(idx, idx)
379 local f = char_func_map[chr]
380 if f then
381 return f(str, idx)
382 end
383 decode_error(str, idx, "unexpected character '" .. chr .. "'")
384end
385
386
387function json.decode(str)
388 if type(str) ~= "string" then
389 error("expected argument of type string, got " .. type(str))
390 end
391 local res, idx = parse(str, next_char(str, 1, space_chars, true))
392 idx = next_char(str, idx, space_chars, true)
393 if idx <= #str then
394 decode_error(str, idx, "trailing garbage")
395 end
396 return res
397end
398
399-- Actual program
400
401local function getGistFile(data)
402 if not data.truncated then return data.content else
403 local handle = http.get(data.raw_url)
404 if not handle then error("Could not connect to api.github.com.") end
405 if handle.getResponseCode() ~= 200 then handle.close(); error("Failed to download file data.") end
406 local d = handle.readAll()
407 handle.close()
408 return d
409 end
410end
411
412-- ID can be either just the gist ID or a gist ID followed by a slash and a file name
413-- * If a file name is specified, retrieves that file
414-- * Otherwise, if there's only one file, retrieves that file
415-- * Otherwise, if there's a file named 'init.lua', retrieves 'init.lua'
416-- * Otherwise, if there's more than one file but only one *.lua file, retrieves the Lua file
417-- * Otherwise, retrieves the first Lua file alphabetically (with a warning)
418-- * Otherwise, fails
419local function getGistData(id)
420 local file
421 if id:find("/") ~= nil then id, file = id:match("^([0-9A-Fa-f]+)/(.+)$") end
422 write("Connecting to api.github.com... ")
423 local handle = http.get("https://api.github.com/gists/" .. id)
424 if handle == nil then print("Failed."); return nil end
425 if handle.getResponseCode() ~= 200 then print("Failed."); handle.close(); return nil end
426 local meta = json.decode(handle.readAll())
427 handle.close()
428 if meta == nil or meta.files == nil then print("Failed."); return nil end
429 print("Success.")
430 if file then return getGistFile(meta.files[file]), file
431 elseif next(meta.files, next(meta.files)) == nil then return getGistFile(meta.files[next(meta.files)]), next(meta.files)
432 elseif meta.files["init.lua"] ~= nil then return getGistFile(meta.files["init.lua"]), "init.lua"
433 else
434 local luaFiles = {}
435 for k in pairs(meta.files) do if k:match("%.lua$") then table.insert(luaFiles, k) end end
436 table.sort(luaFiles)
437 if #luaFiles == 0 then
438 print("Error: Could not find any Lua files to download!")
439 return nil
440 end
441 if #luaFiles > 1 then print("Warning: More than one Lua file detected, downloading the first one alphabetically.") end
442 return getGistFile(meta.files[luaFiles[1]]), luaFiles[1]
443 end
444end
445
446local args = {...}
447
448if #args < 2 then
449 print("Usages:\ngist put <filename> [description]\ngist get <id> <filename>\ngist run <id> [arguments...]")
450 return 1
451end
452
453if not http then
454 printError("Gist requires http API" )
455 printError("Set http_enable to true in ComputerCraft.cfg")
456 return 2
457end
458
459if args[1] == "get" then
460 if #args < 3 then print("Usages:\ngist put <filename> [description]\ngist get <id> <filename>\ngist run <id> [arguments...]"); return 1 end
461 local data = getGistData(args[2])
462 if data == nil then return 3 end
463 local file = fs.open(shell.resolve(args[3]), "w")
464 file.write(data)
465 file.close()
466 print("Downloaded as " .. shell.resolve(args[3]))
467elseif args[1] == "run" then
468 local data, name = getGistData(args[2])
469 if data == nil then return 3 end
470 local fn, err = load(data, name, "t", _ENV)
471 if fn == nil then error(err) end
472 local ok, msg = fn(table.unpack(args, 3))
473 if not ok then error(msg) end
474elseif args[1] == "put" then
475 local data = {files = {}, public = true}
476 local i = 2
477 while args[i] ~= nil and args[i] ~= "--" do
478 if data.files[fs.getName(args[i])] then error("Cannot upload files with duplicate names.") end
479 local file = fs.open(shell.resolve(args[i]), "r")
480 if file == nil then error("Could not read " .. shell.resolve(args[i]) .. ".") end
481 data.files[fs.getName(args[i])] = {content = file.readAll()}
482 file.close()
483 i=i+1
484 end
485 if args[i] == "--" then data.description = table.concat({table.unpack(args, i+1)}, " ") end
486 -- Get authorization
487 local headers = {["Content-Type"] = "application/json"}
488 if settings.get("gist.id") ~= nil then headers.Authorization = "token " .. settings.get("gist.id") else
489 local id = math.random(0, 999999)
490 print("Authorization is required to post a gist.\nPlease visit http://cppconsole.bruienne.com/cc-gist/ and enter this code:\n" .. id)
491 while true do
492 local handle = http.get("http://cppconsole.bruienne.com/cc-gist/await_token.php?token=" .. id)
493 if handle then
494 if handle.getResponseCode() == 200 then
495 local auth = json.decode(handle.readAll())
496 if auth.access_token ~= nil and auth.scope == "gist" then
497 settings.set("gist.id", auth.access_token)
498 settings.save(".settings")
499 headers.Authorization = "token " .. auth.access_token
500 handle.close()
501 break
502 else print("An error occurred.") end
503 end
504 handle.close()
505 end
506 sleep(1)
507 end
508 end
509 local jsonfiles = ""
510 for k,v in pairs(data.files) do jsonfiles = jsonfiles .. (jsonfiles == "" and "" or ",\n") .. (" \"%s\": {\n \"content\": %s\n }"):format(k, json.encode(v.content)) end
511 local jsondata = ([[{
512 "description": %s,
513 "public": true,
514 "files": {
515%s
516 }
517}]]):format(data.description and '"' .. data.description .. '"' or "null", jsonfiles)
518 print(jsondata)
519 write("Connecting to api.github.com... ")
520 local handle = http.post("https://api.github.com/gists", jsondata, headers)
521 if handle == nil then print("Failed."); return 3 end
522 local resp = json.decode(handle.readAll())
523 if handle.getResponseCode() ~= 201 or resp == nil then print("Failed: " .. handle.getResponseCode() .. ": " .. (resp and json.encode(resp) or "")); handle.close(); return 3 end
524 handle.close()
525 print("Success. Uploaded as " .. resp.id .. "\nRun 'gist get " .. resp.id .. "' to download anywhere")
526else print("Usages:\ngist put <filenames...> [-- description...]\ngist get <id> <filename>\ngist run <id> [arguments...]"); return 1 end