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module CodeRay
module Scanners
class C < Scanner
register_for :c
include Streamable
RESERVED_WORDS = [
'asm', 'break', 'case', 'continue', 'default', 'do', 'else',
'for', 'goto', 'if', 'return', 'switch', 'while',
'struct', 'union', 'enum', 'typedef',
'static', 'register', 'auto', 'extern',
'sizeof',
'volatile', 'const', # C89
'inline', 'restrict', # C99
]
PREDEFINED_TYPES = [
'int', 'long', 'short', 'char', 'void',
'signed', 'unsigned', 'float', 'double',
'bool', 'complex', # C99
]
PREDEFINED_CONSTANTS = [
'EOF', 'NULL',
'true', 'false', # C99
]
IDENT_KIND = WordList.new(:ident).
add(RESERVED_WORDS, :reserved).
add(PREDEFINED_TYPES, :pre_type).
add(PREDEFINED_CONSTANTS, :pre_constant)
ESCAPE = / [rbfnrtv\n\\'"] | x[a-fA-F0-9]{1,2} | [0-7]{1,3} /x
UNICODE_ESCAPE = / u[a-fA-F0-9]{4} | U[a-fA-F0-9]{8} /x
def scan_tokens tokens, options
state = :initial
until eos?
kind = nil
match = nil
case state
when :initial
if scan(/ \s+ | \\\n /x)
kind = :space
elsif scan(%r! // [^\n\\]* (?: \\. [^\n\\]* )* | /\* (?: .*? \*/ | .* ) !mx)
kind = :comment
elsif match = scan(/ \# \s* if \s* 0 /x)
match << scan_until(/ ^\# (?:elif|else|endif) .*? $ | \z /xm) unless eos?
kind = :comment
elsif scan(/ [-+*\/=<>?:;,!&^|()\[\]{}~%]+ | \.(?!\d) /x)
kind = :operator
elsif match = scan(/ [A-Za-z_][A-Za-z_0-9]* /x)
kind = IDENT_KIND[match]
if kind == :ident and check(/:(?!:)/)
match << scan(/:/)
kind = :label
end
elsif match = scan(/L?"/)
tokens << [:open, :string]
if match[0] == ?L
tokens << ['L', :modifier]
match = '"'
end
state = :string
kind = :delimiter
elsif scan(/#\s*(\w*)/)
kind = :preprocessor # FIXME multiline preprocs
state = :include_expected if self[1] == 'include'
elsif scan(/ L?' (?: [^\'\n\\] | \\ #{ESCAPE} )? '? /ox)
kind = :char
elsif scan(/0[xX][0-9A-Fa-f]+/)
kind = :hex
elsif scan(/(?:0[0-7]+)(?![89.eEfF])/)
kind = :oct
elsif scan(/(?:\d+)(?![.eEfF])/)
kind = :integer
elsif scan(/\d[fF]?|\d*\.\d+(?:[eE][+-]?\d+)?[fF]?|\d+[eE][+-]?\d+[fF]?/)
kind = :float
else
getch
kind = :error
end
when :string
if scan(/[^\\\n"]+/)
kind = :content
elsif scan(/"/)
tokens << ['"', :delimiter]
tokens << [:close, :string]
state = :initial
next
elsif scan(/ \\ (?: #{ESCAPE} | #{UNICODE_ESCAPE} ) /mox)
kind = :char
elsif scan(/ \\ | $ /x)
tokens << [:close, :string]
kind = :error
state = :initial
else
raise_inspect "else case \" reached; %p not handled." % peek(1), tokens
end
when :include_expected
if scan(/[^\n]+/)
kind = :include
state = :initial
elsif match = scan(/\s+/)
kind = :space
state = :initial if match.index ?\n
else
getch
kind = :error
end
else
raise_inspect 'Unknown state', tokens
end
match ||= matched
if $DEBUG and not kind
raise_inspect 'Error token %p in line %d' %
[[match, kind], line], tokens
end
raise_inspect 'Empty token', tokens unless match
tokens << [match, kind]
end
if state == :string
tokens << [:close, :string]
end
tokens
end
end
end
end
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