Class: CDDL::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/cddl.rb

Constant Summary collapse

REGEXP_FOR_STRING =

Memoize a bit here

Hash.new {|h, k|
  h[k] = Regexp.new("\\A#{k}\\z")
}
VALUE_TYPE = 
{string: String, int: Integer, float: Float}
SIMPLE_VALUE = 
{
  [:prim, 7, 20] => [true, false, :bool],
  [:prim, 7, 21] => [true, true, :bool],
  [:prim, 7, 22] => [true, nil, :nil],
  [:prim, 7, 23] => [true, :undefined, :undefined],
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(source_text) ⇒ Parser

Returns a new instance of Parser.



22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
 
# File 'lib/cddl.rb', line 22

def initialize(source_text)
  @abnf = Peggy::ABNF.new
  _cresult = @abnf.compile! ABNF_SPEC, ignore: :s
  presult = @abnf.parse? :cddl, (source_text + PRELUDE)
  expected_length = source_text.length + PRELUDE.length
  if expected_length != presult
    upto = @abnf.parse_results.keys.max
    puts "UPTO: #{upto}" if $advanced
    pp @abnf.parse_results[upto] if $advanced
    pp @abnf.parse_results[presult] if $advanced
    puts "SO FAR: #{presult}"  if $advanced
    puts @abnf.ast? if $advanced
    presult ||= 0
    part1 = source_text[[presult - 100, 0].max...presult]
    part3 = source_text[upto...[upto + 100, source_text.length].min]
    if upto - presult < 100
      part2 = source_text[presult...upto]
    else
      part2 = source_text[presult, 50] + "......." + source_text[upto-50, 50]
    end
    warn "*** Look for syntax problems around the #{
           "%%%".colorize(background: :light_yellow)} markers:\n#{
           part1}#{"%%%".colorize(color: :green, background: :light_yellow)}#{
           part2}#{"%%%".colorize(color: :red, background: :light_yellow)}#{
           part3}"
    raise ParseError, "*** Parse error at #{presult} upto #{upto} of #{
                      source_text.length} (#{expected_length})."
  end
  puts @abnf.ast? if $debug_ast
  @ast = @abnf.ast?
  # our little argument stack for rule processing
  @insides = []
end

Instance Attribute Details

#ast ⇒ Object (readonly)

Returns the value of attribute ast.



458
459
460
 
# File 'lib/cddl.rb', line 458

def ast
  @ast
end

Instance Method Details

#apr ⇒ Object

for debugging



56
57
58
 
# File 'lib/cddl.rb', line 56

def apr                     # for debugging
  @abnf.parse_results
end

#extract_value(t) ⇒ Object 



255
256
257
258
259
260
261
262
263
 
# File 'lib/cddl.rb', line 255

def extract_value(t)
  if vt = VALUE_TYPE[t[0]]
    [true, t[1], vt]
  elsif v = SIMPLE_VALUE[t]
    v
  else
    [false]
  end
end

#generate ⇒ Object 



124
125
126
127
 
# File 'lib/cddl.rb', line 124

def generate
  @recursion = 0
  generate1(rules)
end

#generate1(where, inmap = false) ⇒ Object 



129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
 
# File 'lib/cddl.rb', line 129

def generate1(where, inmap = false)
  case where[0]
  when :type1
    generate1(where[rand(where.size-1)+1])
  when :map
    Hash[where[1..-1].flat_map {|m| generate1(m, true)}]
  when :array, :grpent
    r = where[1..-1].flat_map {|m| generate1(m).map{|e| e[1]}}
        .flat_map {|e| Array === e && e[0] == :grpent ? e[1..-1] : [e]}
                       # nested grpents need to be "unpacked"
    if where[0] == :grpent
      [:grpent, *r]
    else
      r
    end
  when :member
    st = where[1]
    en = [where[2], [st, 4].max].min # truncate to 4 unless must be more
    st += rand(en + 1 - st) if en != st
    kr = where[3]
    vr = where[4]
    fail "member key not given in map for #{where}" unless kr if inmap
    Array.new(st) { [ (generate1(kr) if kr), # XXX: need error in map context
                     generate1(vr)
                   ]}
  when :string, :int, :float
    where[1]
  when :range
    rand(where[1])
  when :prim
    case where[1]
    when nil
      gen_word              # XXX: maybe always returning a string is confusing
    when 0
      rand(4711)
    when 1
      ~rand(815)
    when 2
      gen_word.force_encoding(Encoding::BINARY)
    when 3
      gen_word
    when 6
      CBOR::Tagged.new(where[2], generate1(where[3]))
    when 7
      case where[2]
      when nil
        Math::PI
      when 20
        false
      when 21
        true
      when 22
        nil
      when 23
        :undefined
      when 25, 26, 27
        rand()
      end
    else
      fail "Can't generate prim #{where[1]}"
    end
  when :anno
    target = where[2]
    control = where[3]
    case where[1]
    when :size
      should_be_int = generate1(control)
      unless target == [:prim, 2] && Integer === should_be_int
        fail "Don't know yet how to generate #{where}"
      end
      Random.new.bytes(should_be_int)
    when :bits
      set_of_bits = Array.new(10) { generate1(control) } # XXX: ten?
      # p set_of_bits
      unless (target == [:prim, 0] || target == [:prim, 2]) &&
             set_of_bits.all? {|x| Integer === x && x >= 0 }
        fail "Don't know yet how to generate #{where}"
      end
      if target == [:prim, 2]
        set_of_bits.inject(String.new) do |s, i|
          n = i >> 3
          bit = 1 << (i & 7)
          if v = s.getbyte(n)
            s.setbyte(n, v | bit); s
          else
            s << "\0" * (n - s.size) << bit.chr(Encoding::BINARY)
          end
        end
      else                  # target == [:prim, 0]
        set_of_bits.inject(0) do |a, v|
          a |= (1 << v)
        end
      end
    when :regexp
      regexp = generate1(control)
      unless target == [:prim, 3] && String === regexp
        fail "Don't know yet how to generate #{where}"
      end
      REGEXP_FOR_STRING[regexp].random_example(max_repeater_variance: 5)
    else
      fail "Don't know yet how to generate from #{where}"
    end
  when :recurse
    name = where[1]
    rule = @stage1[name]
    if @recursion < MAX_RECURSE
      @recursion += 1
      r = generate1(rule)
      @recursion -= 1
      r
    else
      fail "Deep recursion into #{name}: #{@stage1[name]}, not yet implemented"
    end
  else
    fail "Don't know how to generate from #{where[0]}"
  end
end

#rules ⇒ Object 



66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
 
# File 'lib/cddl.rb', line 66

def rules
  @rules = {}
  @generics = {}
  @bindings = [{}]
  ast.each :rule do |rule|
    rule_ast =
      if rulename = rule.groupname
        [:grpent, *rule.group.children(:grpent)]
      elsif rulename = rule.typename
        [:type1, *rule.type.children(:type1)]
      else
        fail "Huh?"
      end
    n = rulename.to_s
    if g = rule.genericparm
      ids = g.children(:id).map(&:to_s)
      # puts ["ids", ids].inspect
      if b = @generics[n]
        fail "Duplicate generics definition #{n} as #{rule_ast} (was #{b})"
      end
      @generics[n] = [rule_ast, ids]
    else
      if @rules[n]
        a = strip_nodes(rule_ast).inspect
        b = strip_nodes(@rules[n]).inspect
        if a == b
          warn "*** Warning: Identical redefinition of #{n} as #{a}"
        else
          fail "Duplicate rule definition #{n} as #{b} (was #{a})"
        end
      end
      @rules[n] = rule_ast
    end
  end
  # pp @generics
  @rootrule = @rules.keys.first # DRAFT: generics are ignored here.
  # now process the rules...
  @stage1 = {}
  result = r_process(@rootrule, @rules[@rootrule])
  r_process("used_in_cddl_prelude", @rules["used_in_cddl_prelude"])
  @rules.each do |n, r|
  #   r_process(n, r)     # debug only loop
    warn "*** Unused rule #{n}" unless @stage1[n]
  end
  if result[0] == :grpent
    warn "Group at top -- first rule must be a type!"
  end
  # end
  # @stage1
  result
end

#strip_nodes(n) ⇒ Object 



60
61
62
63
64
 
# File 'lib/cddl.rb', line 60

def strip_nodes(n)
  [n[0], *n[1..-1].map {|e|
    e._strip
  }]
end

#validate(d, warn = true) ⇒ Object 



269
270
271
272
273
274
275
276
277
278
279
 
# File 'lib/cddl.rb', line 269

def validate(d, warn=true)
  @recursion = 0
  result = validate1(d)
  unless result
    if warn
      warn "CDDL validation failure:"
      PP::pp(validate_diag, STDERR)
    end
  end
  result
end

#validate1(d, where = rules) ⇒ Object 



318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
 
# File 'lib/cddl.rb', line 318

def validate1(d, where=rules)
#      puts "DATA: #{d.inspect}"
#      puts "RULE: #{where.inspect}"
  @last_data = d
  @last_rule = where
  case where[0]
  when :type1
    where[1..-1].any? {|r| validate1(d, r)}
  when :map
    if Hash === d
      d_check = d.dup
      where[1..-1].all? { |r|
        # puts "SUBRULE: #{r.inspect}"
        t, s, _e, k, v = r
        fail unless t == :member
        # this is mostly quadratic; let's do the linear thing if possible
        fail "member name not known for group entry #{r} in map" unless k
        simple, simpleval = extract_value(k)
        if simple
#              puts "SIMPLE: #{d_check.inspect} #{simpleval}"
          # add occurrence check; check that val is present in the first place
          actual = d.fetch(simpleval, :not_found)
          if actual == :not_found
            s == 0          # minimum occurrence must be 0 then
          else
            validate1(actual, v) && d_check.delete(simpleval)
          end
        else
#              puts "COMPLEX: #{k.inspect} #{simple.inspect} #{simpleval.inspect}"
          keys = d_check.keys
          ta, keys = keys.partition{ |key| validate1(key, k)}
          # XXX check ta.size against s/e
          ta.all? { |val|
            validate1(d[val], v) && d_check.delete(val)
          }
        end
      } && d_check == {}
    end
  when :array
    if Array === d
      # validate1 against the record
      i = validate_forward(d, 0, where)
      validate_result(i == d.size) { "cannot complete array #{d} for #{where}" }
    end
  when :string, :int, :float
    _, v = extract_value(where)
    d == v
  when :range
    where[2] === d && where[1].include?(d)
  when :anno
    target = where[2]
    if validate1(d, target)
      control = where[3]
      case where[1]
      when :size
        validate1(d.bytesize, control)
      when :bits
        if String === d
          d.each_byte.with_index.all? { |b, i|
            bit = i << 3
            8.times.all? { |nb|
              b[nb] == 0 || validate1(bit+nb, control)
            }
          }
        elsif Integer === d
          if d >= 0
            ok = true
            i = 0
            while ok && d > 0
              if d.odd?
                ok &&= validate1(i, control)
              end
              d >>= 1; i += 1
            end
            ok
          end
        end
      when :regexp
        if String === d
          ok, v, vt = extract_value(control)
          if ok && vt == String
            re = REGEXP_FOR_STRING[v]
            # pp re
            d.match(re)
          end
        end
      else
        fail "Don't know yet how to validate against #{where}"
      end
    end
  when :prim
    # warn "validate prim WI #{where.inspect} #{d.inspect}"
    case where[1]
    when nil
      true
    when 0
      Integer === d && d >= 0 && d <= 0xffffffffffffffff
    when 1
      Integer === d && d < 0 && d >= -0x10000000000000000
    when 2
      String === d && d.encoding == Encoding::BINARY
    when 3
      String === d && d.encoding != Encoding::BINARY # cheat
    when 6
      CBOR::Tagged === d && d.tag == where[2] && validate1(d.data, where[3])
    when 7
      t, v = extract_value(where)
      if t
        v == d
      else
        case where[2]
        when nil
          # XXX
          fail
        when 25, 26, 27
          Float === d
        else
          fail
        end
      end
    else
      fail "Can't validate prim #{where[1]} yet"
    end
  when :recurse
    name = where[1]
    rule = @stage1[name]
    if @recursion < MAX_RECURSE
      @recursion += 1
      r = validate1(d, rule)
      @recursion -= 1
      r
    else
      fail "Deep recursion into #{name}: #{rule}, not yet implemented"
    end
  else
    # fail where
  end
end

#validate_diag ⇒ Object 



265
266
267
 
# File 'lib/cddl.rb', line 265

def validate_diag
  [@last_data, @last_rule, @last_message]
end

#validate_forward(d, start, where) ⇒ Object 



288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
 
# File 'lib/cddl.rb', line 288

def validate_forward(d, start, where)
  i = 0
  where[1..-1].each { |r|
    t, s, e, _k, v = r # XXX
    fail unless t == :member
    occ = 0
    while ((occ < e) && i != d.size && (n = validate_linear(d, start+i, v)))
      i += n
      occ += 1
    end
    if occ < s
      @last_message = "occur not reached in array #{d} for #{where}"
      return false
    end
  }
  i
end

#validate_linear(d, start, where) ⇒ Object

returns number of matches or false for breakage



307
308
309
310
311
312
313
314
315
316
 
# File 'lib/cddl.rb', line 307

def validate_linear(d, start, where)
  fail unless Array === d
  case where[0]
  when :grpent
    # must be inside an array with nested occurrences
    validate_forward(d, start, where)
  else
    validate1(d[start], where) ? 1 : false
  end
end

#validate_result(check) ⇒ Object 



281
282
283
284
285
286
 
# File 'lib/cddl.rb', line 281

def validate_result(check)
  check || (
    @last_message = yield
    false
  )
end