Class: Origami::LiteralString

Inherits:
String
  • Object
show all
Includes:
String
Defined in:
lib/origami/string.rb,
lib/origami/obfuscation.rb

Overview

Class representing a literal String Object.

Direct Known Subclasses

Date

Constant Summary collapse

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 collapse

Instance Method Summary collapse

Methods included from String

#detect_encoding, #to_pdfdoc, #to_utf16be, #to_utf8

Methods included from Object

#<=>, #cast_to, #copy, #document, #export, included, #indirect?, #indirect_parent, #logicalize, #logicalize!, #native_type, #post_build, #pre_build, #reference, #set_document, #set_indirect, skip_until_next_obj, #solve, #to_o, #type, typeof, #version_required, #xrefs

Constructor Details

#initialize(str = "") ⇒ LiteralString

Creates a new PDF String.

str

The string value.



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# File 'lib/origami/string.rb', line 237

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, _parser = nil) ⇒ Object

:nodoc:



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# File 'lib/origami/string.rb', line 245

def self.parse(stream, _parser = nil) #:nodoc:
    offset = stream.pos

    unless stream.skip(@@regexp_open)
        raise InvalidLiteralStringObjectError, "No literal string start token found"
    end

    result = ""
    depth = 0
    while depth != 0 or stream.peek(1) != TOKENS.last do
        raise InvalidLiteralStringObjectError, "Non-terminated string" if stream.eos?

        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"
                    stream.pos += 1 if stream.peek(1) == "\n"
                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

    unless stream.skip(@@regexp_close)
        raise InvalidLiteralStringObjectError, "Byte string shall be terminated with '#{TOKENS.last}'"
    end

    # Try to cast as a Date object if possible.
    if result[0, 2] == 'D:'
        begin
            date = Date.parse(result)
            date.file_offset = offset
            return date
        rescue InvalidDateError
        end
    end

    bytestr = self.new(result)
    bytestr.file_offset = offset

    bytestr
end

Instance Method Details

#expand ⇒ Object

:nodoc:



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# File 'lib/origami/string.rb', line 317

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



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# File 'lib/origami/string.rb', line 334

def to_hex
    HexaString.new(self.value)
end

#to_s ⇒ Object Also known as: to_obfuscated_str

:nodoc:



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# File 'lib/origami/string.rb', line 327

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

#value ⇒ Object

Returns a standard String representation.



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# File 'lib/origami/string.rb', line 341

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

    to_str
end