Class: Origami::ByteString

Inherits:

String

• Object
• String
• Origami::ByteString

Includes:

String

Defined in:

lib/origami/string.rb,
lib/origami/obfuscation.rb

Overview

Class representing an ASCII String Object.

Direct Known Subclasses

Date

Constant Summary

TOKENS =

:nodoc:

%w{ ( ) }

@@regexp_open =

Regexp.new(WHITESPACES + Regexp.escape(TOKENS.first))

@@regexp_close =

Regexp.new(Regexp.escape(TOKENS.last))

Instance Attribute Summary

Attributes included from String

#encoding

Attributes included from Object

#file_offset, #generation, #no, #objstm_offset, #parent

Class Method Summary

• .parse(stream) ⇒ Object

  :nodoc:.

Instance Method Summary

• #expand ⇒ Object

  :nodoc:.

• #initialize(str = "") ⇒ ByteString constructor

  Creates a new PDF String.

• #to_hex ⇒ Object

  Converts self to HexaString.

• #to_obfuscated_str ⇒ Object
• #to_s ⇒ Object

  :nodoc:.

• #value ⇒ Object

Methods included from String

#infer_encoding, #real_type, #to_pdfdoc, #to_utf16be, #to_utf8

Methods included from Object

#<=>, #copy, #indirect_parent, #is_indirect?, #pdf, #pdf_version_required, #post_build, #pre_build, #reference, #set_indirect, #set_pdf, #size, skip_until_next_obj, #solve, #to_o, #type, typeof, #xrefs

Methods inherited from String

#is_binary_data?, #to_o

Constructor Details

#initialize(str = "") ⇒ ByteString

Creates a new PDF String.

str

The string value.

# File 'lib/origami/string.rb', line 253

def initialize(str = "")
  
  unless str.is_a?(::String)
    raise TypeError, "Expected type String, received #{str.class}."
  end
  
  super(str)
end

Class Method Details

.parse(stream) ⇒ Object

:nodoc:

# File 'lib/origami/string.rb', line 262

def self.parse(stream) #:nodoc:

  offset = stream.pos
  
  if not stream.skip(@@regexp_open)
    raise InvalidByteStringObjectError, "No literal string start token found"
  end
  
  result = ""
  depth = 0
  while depth != 0 or stream.peek(1) != TOKENS.last do

    if stream.eos?
      raise InvalidByteStringObjectError, "Non-terminated string"
    end

    c = stream.get_byte
    case c
    when "\\"
      if stream.match?(/\d{1,3}/)
        oct = stream.peek(3).oct.chr
        stream.pos += 3
        result << oct
      elsif stream.match?(/((\r?\n)|(\r\n?))/)
        
        stream.skip(/((\r?\n)|(\r\n?))/)
        next
        
      else
        flag = stream.get_byte
        case flag
        when "n" then result << "\n"
        when "r" then result << "\r"
        when "t" then result << "\t"
        when "b" then result << "\b"
        when "f" then result << "\f"
        when "(" then result << "("
        when ")" then result << ")"
        when "\\" then result << "\\"
        when "\r"
          if str.peek(1) == "\n" then stream.pos += 1 end
        when "\n"
        else
          result << flag
        end
      end
        
    when "(" then
      depth = depth + 1
      result << c
    when  ")" then
      depth = depth - 1
      result << c
    else
      result << c
    end

  end

  if not stream.skip(@@regexp_close)
    raise InvalidByteStringObjectError, "Byte string shall be terminated with '#{TOKENS.last}'"
  end

  bytestr = ByteString.new(result)
  bytestr.file_offset

  bytestr
end

Instance Method Details

#expand ⇒ Object

:nodoc:

# File 'lib/origami/string.rb', line 331

def expand #:nodoc:
  
  extended = self.gsub("\\", "\\\\\\\\")
  extended.gsub!(/\)/, "\\)")
  extended.gsub!("\n", "\\n")
  extended.gsub!("\r", "\\r")
  extended.gsub!(/\(/, "\\(")
  
  extended
end

#to_hex ⇒ Object

Converts self to HexaString

# File 'lib/origami/string.rb', line 349

def to_hex
  HexaString.new(self.value)
end

#to_obfuscated_str ⇒ Object

# File 'lib/origami/obfuscation.rb', line 173

def to_obfuscated_str
  to_s
end

#to_s ⇒ Object

:nodoc:

# File 'lib/origami/string.rb', line 342

def to_s #:nodoc:
  super(TOKENS.first + self.expand + TOKENS.last)
end

#value ⇒ Object

# File 'lib/origami/string.rb', line 353

def value
  self.decrypt! if self.is_a?(Encryption::EncryptedString) and not @decrypted

  to_str
end