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20.2 kBtext/coffeescriptView Raw
1
2
3
4############################################################################################################
5CND = require 'cnd'
6rpr = CND.rpr
7badge = 'HOLLERITH/CODEC'
8debug = CND.get_logger 'debug', badge
9warn = CND.get_logger 'warn', badge
10#...........................................................................................................
11CND.shim()
12
13
14#-----------------------------------------------------------------------------------------------------------
15@[ 'typemarkers' ] = {}
16#...........................................................................................................
17tm_lo = @[ 'typemarkers' ][ 'lo' ] = 0x00
18tm_null = @[ 'typemarkers' ][ 'null' ] = 'B'.codePointAt 0
19tm_false = @[ 'typemarkers' ][ 'false' ] = 'C'.codePointAt 0
20tm_true = @[ 'typemarkers' ][ 'true' ] = 'D'.codePointAt 0
21tm_list = @[ 'typemarkers' ][ 'list' ] = 'E'.codePointAt 0
22tm_date = @[ 'typemarkers' ][ 'date' ] = 'G'.codePointAt 0
23tm_ninfinity = @[ 'typemarkers' ][ 'ninfinity' ] = 'J'.codePointAt 0
24tm_nnumber = @[ 'typemarkers' ][ 'nnumber' ] = 'K'.codePointAt 0
25tm_pnumber = @[ 'typemarkers' ][ 'pnumber' ] = 'L'.codePointAt 0
26tm_pinfinity = @[ 'typemarkers' ][ 'pinfinity' ] = 'M'.codePointAt 0
27tm_text = @[ 'typemarkers' ][ 'text' ] = 'T'.codePointAt 0
28tm_private = @[ 'typemarkers' ][ 'private' ] = 'Z'.codePointAt 0
29tm_hi = @[ 'typemarkers' ][ 'hi' ] = 0xff
30
31#-----------------------------------------------------------------------------------------------------------
32@[ 'bytecounts' ] = {}
33bytecount_singular = @[ 'bytecounts' ][ 'singular' ] = 1
34bytecount_typemarker = @[ 'bytecounts' ][ 'typemarker' ] = 1
35bytecount_number = @[ 'bytecounts' ][ 'number' ] = 9
36bytecount_date = @[ 'bytecounts' ][ 'date' ] = bytecount_number + 1
37
38#-----------------------------------------------------------------------------------------------------------
39@[ 'sentinels' ] = {}
40#...........................................................................................................
41### http://www.merlyn.demon.co.uk/js-datex.htm ###
42@[ 'sentinels' ][ 'firstdate' ] = new Date -8640000000000000
43@[ 'sentinels' ][ 'lastdate' ] = new Date +8640000000000000
44
45#-----------------------------------------------------------------------------------------------------------
46@[ 'keys' ] = {}
47#...........................................................................................................
48@[ 'keys' ][ 'lo' ] = new Buffer [ @[ 'typemarkers' ][ 'lo' ] ]
49@[ 'keys' ][ 'hi' ] = new Buffer [ @[ 'typemarkers' ][ 'hi' ] ]
50
51#-----------------------------------------------------------------------------------------------------------
52@[ 'symbols' ] = {}
53symbol_fallback = @[ 'fallback' ] = Symbol 'fallback'
54
55
56#===========================================================================================================
57# RESULT BUFFER (RBUFFER)
58#-----------------------------------------------------------------------------------------------------------
59rbuffer_min_size = 1024
60rbuffer_max_size = 65536
61rbuffer = new Buffer rbuffer_min_size
62
63#-----------------------------------------------------------------------------------------------------------
64grow_rbuffer = ->
65 factor = 2
66 new_size = Math.floor rbuffer.length * factor + 0.5
67 # warn "growing rbuffer to #{new_size} bytes"
68 new_result_buffer = new Buffer new_size
69 rbuffer.copy new_result_buffer
70 rbuffer = new_result_buffer
71 return null
72
73#-----------------------------------------------------------------------------------------------------------
74release_extraneous_rbuffer_bytes = ->
75 if rbuffer.length > rbuffer_max_size
76 # warn "shrinking rbuffer to #{rbuffer_max_size} bytes"
77 rbuffer = new Buffer rbuffer_max_size
78 return null
79
80
81#===========================================================================================================
82# VARIANTS
83#-----------------------------------------------------------------------------------------------------------
84write_singular = ( idx, value ) ->
85 grow_rbuffer() until rbuffer.length >= idx + bytecount_singular
86 if value is null then typemarker = tm_null
87 else if value is false then typemarker = tm_false
88 else if value is true then typemarker = tm_true
89 else throw new Error "unable to encode value of type #{CND.type_of value}"
90 rbuffer[ idx ] = typemarker
91 return idx + bytecount_singular
92
93#-----------------------------------------------------------------------------------------------------------
94read_singular = ( buffer, idx ) ->
95 switch typemarker = buffer[ idx ]
96 when tm_null then value = null
97 when tm_false then value = false
98 when tm_true then value = true
99 else throw new Error "unable to decode 0x#{typemarker.toString 16} at index #{idx} (#{rpr buffer})"
100 return [ idx + bytecount_singular, value, ]
101
102
103#===========================================================================================================
104# PRIVATES
105#-----------------------------------------------------------------------------------------------------------
106write_private = ( idx, value, encoder ) ->
107 grow_rbuffer() until rbuffer.length >= idx + 3 * bytecount_typemarker
108 #.........................................................................................................
109 rbuffer[ idx ] = tm_private
110 idx += bytecount_typemarker
111 #.........................................................................................................
112 rbuffer[ idx ] = tm_list
113 idx += bytecount_typemarker
114 #.........................................................................................................
115 type = value[ 'type' ] ? 'private'
116 value = value[ 'value' ]
117 #.........................................................................................................
118 if encoder?
119 encoded_value = encoder type, value, symbol_fallback
120 value = encoded_value unless encoded_value is symbol_fallback
121 #.........................................................................................................
122 wrapped_value = [ type, value, ]
123 idx = _encode wrapped_value, idx
124 #.........................................................................................................
125 rbuffer[ idx ] = tm_lo
126 idx += bytecount_typemarker
127 #.........................................................................................................
128 return idx
129
130#-----------------------------------------------------------------------------------------------------------
131read_private = ( buffer, idx, decoder ) ->
132 idx += bytecount_typemarker
133 [ idx, [ type, value, ] ] = read_list buffer, idx
134 if decoder?
135 R = decoder type, value, symbol_fallback
136 throw new Error "encountered illegal value `undefined` when reading private type" if R is undefined
137 if R is symbol_fallback or not decoder?
138 R = { type, value, }
139 return [ idx, R, ]
140
141
142#===========================================================================================================
143# NUMBERS
144#-----------------------------------------------------------------------------------------------------------
145write_number = ( idx, number ) ->
146 grow_rbuffer() until rbuffer.length >= idx + bytecount_number
147 if number < 0
148 type = tm_nnumber
149 number = -number
150 else
151 type = tm_pnumber
152 rbuffer[ idx ] = type
153 rbuffer.writeDoubleBE number, idx + 1
154 _invert_buffer rbuffer, idx if type is tm_nnumber
155 return idx + bytecount_number
156
157#-----------------------------------------------------------------------------------------------------------
158write_infinity = ( idx, number ) ->
159 grow_rbuffer() until rbuffer.length >= idx + bytecount_singular
160 rbuffer[ idx ] = if number is -Infinity then tm_ninfinity else tm_pinfinity
161 return idx + bytecount_singular
162
163#-----------------------------------------------------------------------------------------------------------
164read_nnumber = ( buffer, idx ) ->
165 throw new Error "not a negative number at index #{idx}" unless buffer[ idx ] is tm_nnumber
166 copy = _invert_buffer ( new Buffer buffer.slice idx, idx + bytecount_number ), 0
167 return [ idx + bytecount_number, -( copy.readDoubleBE 1 ), ]
168
169#-----------------------------------------------------------------------------------------------------------
170read_pnumber = ( buffer, idx ) ->
171 throw new Error "not a positive number at index #{idx}" unless buffer[ idx ] is tm_pnumber
172 return [ idx + bytecount_number, buffer.readDoubleBE idx + 1, ]
173
174#-----------------------------------------------------------------------------------------------------------
175_invert_buffer = ( buffer, idx ) ->
176 buffer[ i ] = ~buffer[ i ] for i in [ idx + 1 .. idx + 8 ]
177 return buffer
178
179
180#===========================================================================================================
181# DATES
182#-----------------------------------------------------------------------------------------------------------
183write_date = ( idx, date ) ->
184 grow_rbuffer() until rbuffer.length >= idx + bytecount_date
185 number = +date
186 rbuffer[ idx ] = tm_date
187 return write_number idx + 1, number
188
189#-----------------------------------------------------------------------------------------------------------
190read_date = ( buffer, idx ) ->
191 throw new Error "not a date at index #{idx}" unless buffer[ idx ] is tm_date
192 switch type = buffer[ idx + 1 ]
193 when tm_nnumber then [ idx, value, ] = read_nnumber buffer, idx + 1
194 when tm_pnumber then [ idx, value, ] = read_pnumber buffer, idx + 1
195 else throw new Error "unknown date type marker 0x#{type.toString 16} at index #{idx}"
196 return [ idx, ( new Date value ), ]
197
198
199#===========================================================================================================
200# TEXTS
201#-----------------------------------------------------------------------------------------------------------
202write_text = ( idx, text ) ->
203 text = text.replace /\x01/g, '\x01\x02'
204 text = text.replace /\x00/g, '\x01\x01'
205 bytecount_text = ( Buffer.byteLength text, 'utf-8' ) + 2
206 grow_rbuffer() until rbuffer.length >= idx + bytecount_text
207 rbuffer[ idx ] = tm_text
208 rbuffer.write text, idx + 1
209 rbuffer[ idx + bytecount_text - 1 ] = tm_lo
210 return idx + bytecount_text
211
212#-----------------------------------------------------------------------------------------------------------
213read_text = ( buffer, idx ) ->
214 # urge '©J2d6R', buffer[ idx ], buffer[ idx ] is tm_text
215 throw new Error "not a text at index #{idx}" unless buffer[ idx ] is tm_text
216 stop_idx = idx
217 loop
218 stop_idx += +1
219 break if ( byte = buffer[ stop_idx ] ) is tm_lo
220 throw new Error "runaway string at index #{idx}" unless byte?
221 R = buffer.toString 'utf-8', idx + 1, stop_idx
222 R = R.replace /\x01\x01/g, '\x00'
223 R = R.replace /\x01\x02/g, '\x01'
224 return [ stop_idx + 1, R, ]
225
226
227#===========================================================================================================
228# LISTS
229#-----------------------------------------------------------------------------------------------------------
230read_list = ( buffer, idx ) ->
231 throw new Error "not a list at index #{idx}" unless buffer[ idx ] is tm_list
232 R = []
233 idx += +1
234 loop
235 break if ( byte = buffer[ idx ] ) is tm_lo
236 [ idx, value, ] = _decode buffer, idx, true
237 R.push value[ 0 ]
238 throw new Error "runaway list at index #{idx}" unless byte?
239 return [ idx + 1, R, ]
240
241
242#===========================================================================================================
243#
244#-----------------------------------------------------------------------------------------------------------
245write = ( idx, value, encoder ) ->
246 switch type = CND.type_of value
247 when 'text' then return write_text idx, value
248 when 'number' then return write_number idx, value
249 when 'jsinfinity' then return write_infinity idx, value
250 when 'jsdate' then return write_date idx, value
251 #.........................................................................................................
252 return write_private idx, value, encoder if CND.isa_pod value
253 return write_singular idx, value
254
255
256#===========================================================================================================
257# PUBLIC API
258#-----------------------------------------------------------------------------------------------------------
259@encode = ( key, encoder ) ->
260 rbuffer.fill 0x00
261 throw new Error "expected a list, got a #{type}" unless ( type = CND.type_of key ) is 'list'
262 idx = _encode key, 0, encoder
263 R = new Buffer idx
264 rbuffer.copy R, 0, 0, idx
265 release_extraneous_rbuffer_bytes()
266 #.........................................................................................................
267 return R
268
269#-----------------------------------------------------------------------------------------------------------
270@encode_plus_hi = ( key, encoder ) ->
271 ### TAINT code duplication ###
272 rbuffer.fill 0x00
273 throw new Error "expected a list, got a #{type}" unless ( type = CND.type_of key ) is 'list'
274 idx = _encode key, 0, encoder
275 grow_rbuffer() until rbuffer.length >= idx + 1
276 rbuffer[ idx ] = tm_hi
277 idx += +1
278 R = new Buffer idx
279 rbuffer.copy R, 0, 0, idx
280 release_extraneous_rbuffer_bytes()
281 #.........................................................................................................
282 return R
283
284#-----------------------------------------------------------------------------------------------------------
285_encode = ( key, idx, encoder ) ->
286 last_element_idx = key.length - 1
287 for element, element_idx in key
288 try
289 if CND.isa_list element
290 rbuffer[ idx ] = tm_list
291 idx += +1
292 for sub_element in element
293 idx = _encode [ sub_element, ], idx, encoder
294 rbuffer[ idx ] = tm_lo
295 idx += +1
296 else
297 idx = write idx, element, encoder
298 catch error
299 key_rpr = []
300 for element in key
301 if CND.isa_jsbuffer element
302 key_rpr.push "#{@rpr_of_buffer null, key[ 2 ]}"
303 else
304 key_rpr.push rpr element
305 warn "detected problem with key [ #{rpr key_rpr.join ', '} ]"
306 throw error
307 #.........................................................................................................
308 return idx
309
310#-----------------------------------------------------------------------------------------------------------
311@decode = ( buffer, decoder ) ->
312 return ( _decode buffer, 0, false, decoder )[ 1 ]
313
314#-----------------------------------------------------------------------------------------------------------
315_decode = ( buffer, idx, single, decoder ) ->
316 R = []
317 last_idx = buffer.length - 1
318 loop
319 break if idx > last_idx
320 switch type = buffer[ idx ]
321 when tm_list then [ idx, value, ] = read_list buffer, idx
322 when tm_text then [ idx, value, ] = read_text buffer, idx
323 when tm_nnumber then [ idx, value, ] = read_nnumber buffer, idx
324 when tm_ninfinity then [ idx, value, ] = [ idx + 1, -Infinity, ]
325 when tm_pnumber then [ idx, value, ] = read_pnumber buffer, idx
326 when tm_pinfinity then [ idx, value, ] = [ idx + 1, +Infinity, ]
327 when tm_date then [ idx, value, ] = read_date buffer, idx
328 when tm_private then [ idx, value, ] = read_private buffer, idx, decoder
329 else [ idx, value, ] = read_singular buffer, idx
330 R.push value
331 break if single
332 #.........................................................................................................
333 return [ idx, R ]
334
335
336# debug ( require './dump' ).rpr_of_buffer null, buffer = @encode [ 'aaa', [], ]
337# debug '©tP5xQ', @decode buffer
338
339#===========================================================================================================
340#
341#-----------------------------------------------------------------------------------------------------------
342@encodings =
343
344 #.........................................................................................................
345 dbcs2: """
346 ⓪①②③④⑤⑥⑦⑧⑨⑩⑪⑫⑬⑭⑮⑯⑰⑱⑲⑳㉑㉒㉓㉔㉕㉖㉗㉘㉙㉚㉛
347 ㉜！＂＃＄％＆＇（）＊＋，－．／０１２３４５６７８９：；＜＝＞？
348 ＠ＡＢＣＤＥＦＧＨＩＪＫＬＭＮＯＰＱＲＳＴＵＶＷＸＹＺ［＼］＾＿
349 ｀ａｂｃｄｅｆｇｈｉｊｋｌｍｎｏｐｑｒｓｔｕｖｗｘｙｚ｛｜｝～㉠
350 ㉝㉞㉟㊱㊲㊳㊴㊵㊶㊷㊸㊹㊺㊻㊼㊽㊾㊿㋐㋑㋒㋓㋔㋕㋖㋗㋘㋙㋚㋛㋜㋝
351 ㋞㋟㋠㋡㋢㋣㋤㋥㋦㋧㋨㋩㋪㋫㋬㋭㋮㋯㋰㋱㋲㋳㋴㋵㋶㋷㋸㋹㋺㋻㋼㋽
352 ㋾㊊㊋㊌㊍㊎㊏㊐㊑㊒㊓㊔㊕㊖㊗㊘㊙㊚㊛㊜㊝㊞㊟㊠㊡㊢㊣㊤㊥㊦㊧㊨
353 ㊩㊪㊫㊬㊭㊮㊯㊰㊀㊁㊂㊃㊄㊅㊆㊇㊈㊉㉈㉉㉊㉋㉌㉍㉎㉏⓵⓶⓷⓸⓹〓
354 """
355 #.........................................................................................................
356 aleph: """
357 БДИЛЦЧШЭЮƆƋƏƐƔƥƧƸψŐőŒœŊŁłЯɔɘɐɕəɞ
358 ␣!"#$%&'()*+,-./0123456789:;<=>?
359 @ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_
360 `abcdefghijklmnopqrstuvwxyz{|}~ω
361 ΓΔΘΛΞΠΣΦΨΩαβγδεζηθικλμνξπρςστυφχ
362 Ж¡¢£¤¥¦§¨©ª«¬Я®¯°±²³´µ¶·¸¹º»¼½¾¿
363 ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞß
364 àáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ
365 """
366 #.........................................................................................................
367 rdctn: """
368 ∇≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
369 ␣!"#$%&'()*+,-./0123456789:;<=>?
370 @ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_
371 `abcdefghijklmnopqrstuvwxyz{|}~≡
372 ∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃∃
373 ∃∃¢£¤¥¦§¨©ª«¬Я®¯°±²³´µ¶·¸¹º»¼½¾¿
374 ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞß
375 àáâãäåæçèéêëìíîïðñò≢≢≢≢≢≢≢≢≢≢≢≢Δ
376 """
377
378
379#-----------------------------------------------------------------------------------------------------------
380@rpr_of_buffer = ( buffer, encoding ) ->
381 return ( rpr buffer ) + ' ' + @_encode_buffer buffer, encoding
382
383#-----------------------------------------------------------------------------------------------------------
384@_encode_buffer = ( buffer, encoding = 'rdctn' ) ->
385 ### TAINT use switch, emit error if `encoding` not list or known key ###
386 encoding = @encodings[ encoding ] unless CND.isa_list encoding
387 return ( encoding[ buffer[ idx ] ] for idx in [ 0 ... buffer.length ] ).join ''
388
389#-----------------------------------------------------------------------------------------------------------
390@_compile_encodings = ->
391 #.........................................................................................................
392 chrs_of = ( text ) ->
393 text = text.split /([\ud800-\udbff].|.)/
394 return ( chr for chr in text when chr isnt '' )
395 #.........................................................................................................
396 for name, encoding of @encodings
397 encoding = chrs_of encoding.replace /\n+/g, ''
398 unless ( length = encoding.length ) is 256
399 throw new Error "expected 256 characters, found #{length} in encoding #{rpr name}"
400 @encodings[ name ] = encoding
401 return null
402@_compile_encodings()