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Issue with recursive javascript grammar

See original GitHub issue

Hi @h1994st

I’m trying to use nautilus grammars. With ruby grammar just fine, but javascript grammar I have error with it.

cityoflight@v8:~/Grammar-Mutator$ make -j8 GRAMMAR_FILE=grammars/javascript.json
Found antlr-4.8-complete: /usr/local/lib/antlr-4.8-complete.jar
Selected grammar name: javascript (from /home/cityoflight/Grammar-Mutator/grammars/javascript.json)
python3 grammars/f1_c_gen.py /home/cityoflight/Grammar-Mutator/grammars/javascript.json /home/cityoflight/Grammar-Mutator
python3 grammars/f1_c_gen.py /home/cityoflight/Grammar-Mutator/grammars/javascript.json /home/cityoflight/Grammar-Mutator
make[1]: Entering directory '/home/cityoflight/Grammar-Mutator/third_party'
make[2]: Entering directory '/home/cityoflight/Grammar-Mutator/third_party/Cyan4973_xxHash'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/cityoflight/Grammar-Mutator/third_party/Cyan4973_xxHash'
make[2]: Entering directory '/home/cityoflight/Grammar-Mutator/third_party/rxi_map'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/cityoflight/Grammar-Mutator/third_party/rxi_map'
make[2]: Entering directory '/home/cityoflight/Grammar-Mutator/third_party/antlr4-cpp-runtime'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/cityoflight/Grammar-Mutator/third_party/antlr4-cpp-runtime'
make[1]: Leaving directory '/home/cityoflight/Grammar-Mutator/third_party'

^CTraceback (most recent call last):
  File "grammars/f1_c_gen.py", line 646, in <module>
Traceback (most recent call last):
  File "grammars/f1_c_gen.py", line 646, in <module>
    main(json.load(fp), sys.argv[2])
  File "grammars/f1_c_gen.py", line 632, in main
    fuzz_hdr, fuzz_src = CFuzzer(c_grammar).fuzz_src()
  File "grammars/f1_c_gen.py", line 317, in __init__
    main(json.load(fp), sys.argv[2])
  File "grammars/f1_c_gen.py", line 632, in main
    super().__init__(grammar)
  File "grammars/f1_c_gen.py", line 262, in __init__
    self.compute_rule_recursion()
  File "grammars/f1_c_gen.py", line 310, in compute_rule_recursion
    fuzz_hdr, fuzz_src = CFuzzer(c_grammar).fuzz_src()
  File "grammars/f1_c_gen.py", line 317, in __init__
    self.rule_recursion[n] = self.is_rule_recursive(n, rule, set())
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    super().__init__(grammar)
  File "grammars/f1_c_gen.py", line 262, in __init__
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    self.compute_rule_recursion()
  File "grammars/f1_c_gen.py", line 310, in compute_rule_recursion
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  [Previous line repeated 16 more times]
KeyboardInterrupt
    self.rule_recursion[n] = self.is_rule_recursive(n, rule, set())
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  File "grammars/f1_c_gen.py", line 285, in is_rule_recursive
    v = self.is_rule_recursive(rname, trule, seen | {rn})
  [Previous line repeated 15 more times]
  File "grammars/f1_c_gen.py", line 276, in is_rule_recursive
    for token in rule:
KeyboardInterrupt
make: *** [GNUmakefile:102: include/f1_c_fuzz.h] Interrupt
make: *** [GNUmakefile:102: src/f1_c_fuzz.c] Interrupt

I have to stop it with control C. And changing ctx.rule(u'PROGRAM',u'{STATEMENT}\n{PROGRAM}') to ctx.rule(u'PROGRAM',u'{STATEMENT}\n') still get same error.

I don’t know the issue is in the javascript nautilus grammar file, or the generator grammars/f1_c_gen.py. If the recursive issue is in the grammar, what kind of pattern should I avoid?

Issue Analytics

State:
Created 2 years ago
Comments:6

Top GitHub Comments

1reaction

CityOfLight77commented, Dec 21, 2021

Thanks for the help. Now my issues are resolved

0reactions

h1994stcommented, Dec 20, 2021

Hi @CityOfLight77

The added grammar is problematic, because the KEYVALUEOBJECTCONTENT rule is non-terminal. Please see the newly appended line as below:

ctx.rule(u'LITERAL',u'{KEYVALUEOBJECT}')
...
ctx.rule(u'KEYVALUEOBJECT',u'\\{ {KEYVALUEOBJECTCONTENT} \\}')
ctx.rule(u'KEYVALUEOBJECT',u'\\{  \\}')
ctx.rule(u'KEYVALUEOBJECTCONTENT',u'{VAR}: {NUMBER}, {KEYVALUEOBJECTCONTENT}')
ctx.rule(u'KEYVALUEOBJECTCONTENT',u'{VAR}: {NUMBER}')  # <-- this line

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