Class: Gem::SafeMarshal::Reader

Relationships & Source Files
Namespace Children
Exceptions: `DataTooShortError`, `EOFError`, `Error`, `NegativeLengthError`, `NotImplementedError`, `UnconsumedBytesError`, `UnsupportedVersionError`
Inherits:	Object
Defined in:	lib/rubygems/safe_marshal/reader.rb

Constant Summary

EMPTY_ARRAY = private
# File 'lib/rubygems/safe_marshal/reader.rb', line 169
```
Elements::Array.new([].freeze).freeze
```
EMPTY_HASH = private
# File 'lib/rubygems/safe_marshal/reader.rb', line 242
```
Elements::Hash.new([].freeze).freeze
```
EMPTY_STRING = private
# File 'lib/rubygems/safe_marshal/reader.rb', line 145
```
Elements::String.new("".b.freeze).freeze
```
MARSHAL_VERSION = private
# File 'lib/rubygems/safe_marshal/reader.rb', line 42
```
[Marshal::MAJOR_VERSION, Marshal::MINOR_VERSION].map(&:chr).join.freeze
```

OBJECT_LINKS = private

profiling bundle install –full-index shows that offset 6 is by far the most common object link, so we special case it to avoid allocating a new object a third of the time. the following are all the object links that appear more than 10000 times in my profiling

# File 'lib/rubygems/safe_marshal/reader.rb', line 210

{
  6 => Elements::ObjectLink.new(6).freeze,
  30 => Elements::ObjectLink.new(30).freeze,
  81 => Elements::ObjectLink.new(81).freeze,
  34 => Elements::ObjectLink.new(34).freeze,
  38 => Elements::ObjectLink.new(38).freeze,
  50 => Elements::ObjectLink.new(50).freeze,
  91 => Elements::ObjectLink.new(91).freeze,
  42 => Elements::ObjectLink.new(42).freeze,
  46 => Elements::ObjectLink.new(46).freeze,
  150 => Elements::ObjectLink.new(150).freeze,
  100 => Elements::ObjectLink.new(100).freeze,
  104 => Elements::ObjectLink.new(104).freeze,
  108 => Elements::ObjectLink.new(108).freeze,
  242 => Elements::ObjectLink.new(242).freeze,
  246 => Elements::ObjectLink.new(246).freeze,
  139 => Elements::ObjectLink.new(139).freeze,
  143 => Elements::ObjectLink.new(143).freeze,
  114 => Elements::ObjectLink.new(114).freeze,
  308 => Elements::ObjectLink.new(308).freeze,
  200 => Elements::ObjectLink.new(200).freeze,
  54 => Elements::ObjectLink.new(54).freeze,
  62 => Elements::ObjectLink.new(62).freeze,
  1_286_245 => Elements::ObjectLink.new(1_286_245).freeze,
}.freeze

STRING_E_SYMBOL = private
# File 'lib/rubygems/safe_marshal/reader.rb', line 127
```
Elements::Symbol.new("E").freeze
```

Class Method Summary

.new(io) ⇒ Reader constructor

Instance Method Summary

#read!
#read_array private
#read_bignum private
#read_byte private
#read_bytes(n) private
#read_class private
#read_class_or_module private
#read_data private
#read_element private
#read_extended_object private
#read_false private
#read_float private
#read_hash private
#read_hash_with_default_value private
#read_header private
#read_integer private
#read_module private
#read_nil private
#read_object private
#read_object_link private
#read_object_with_ivars private
#read_regexp private
#read_string private
#read_struct private
#read_symbol private
#read_symbol_link private
#read_true private
#read_user_class private
#read_user_defined private
#read_user_marshal private

Constructor Details

.new(io) ⇒ `Reader`

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 29


def initialize(io)
  @io = io
end

Instance Method Details

#read!

Raises:

(UnconsumedBytesError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 33


def read!
  read_header
  root = read_element
  raise UnconsumedBytesError, "expected EOF, got #{@io.read(10).inspect}... after top-level element #{root.class}" unless @io.eof?
  root
end

#read_array (private)

Raises:

(NegativeLengthError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 172


def read_array
  length = read_integer
  return EMPTY_ARRAY if length == 0
  raise NegativeLengthError if length < 0
  elements = Array.new(length) do
    read_element
  end
  Elements::Array.new(elements)
end

#read_bignum (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 284


def read_bignum
  sign = read_byte
  data = read_bytes(read_integer * 2)
  Elements::Bignum.new(sign, data)
end

#read_byte (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 58


def read_byte
  @io.getbyte || raise(EOFError, "Unexpected EOF")
end

#read_bytes(n) (private)

Raises:

(NegativeLengthError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 50


def read_bytes(n)
  raise NegativeLengthError if n < 0
  str = @io.read(n)
  raise EOFError, "expected #{n} bytes, got EOF" if str.nil?
  raise DataTooShortError, "expected #{n} bytes, got #{str.inspect}" unless str.bytesize == n
  str
end

#read_class (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 294


def read_class
  raise NotImplementedError, "Reading Marshal objects of type class is not implemented"
end

#read_class_or_module (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 302


def read_class_or_module
  raise NotImplementedError, "Reading Marshal objects of type class_or_module is not implemented"
end

#read_data (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 306


def read_data
  raise NotImplementedError, "Reading Marshal objects of type data is not implemented"
end

#read_element (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 94


def read_element
  type = read_byte
  case type
  when 34 then read_string # ?"
  when 48 then read_nil # ?0
  when 58 then read_symbol # ?:
  when 59 then read_symbol_link # ?;
  when 64 then read_object_link # ?@
  when 70 then read_false # ?F
  when 73 then read_object_with_ivars # ?I
  when 84 then read_true # ?T
  when 85 then read_user_marshal # ?U
  when 91 then read_array # ?[
  when 102 then read_float # ?f
  when 105 then Elements::Integer.new(read_integer) # ?i
  when 108 then read_bignum # ?l
  when 111 then read_object # ?o
  when 117 then read_user_defined # ?u
  when 123 then read_hash # ?{
  when 125 then read_hash_with_default_value # ?}
  when 101 then read_extended_object # ?e
  when 99 then read_class # ?c
  when 109 then read_module # ?m
  when 77 then read_class_or_module # ?M
  when 100 then read_data # ?d
  when 47 then read_regexp # ?/
  when 83 then read_struct # ?S
  when 67 then read_user_class # ?C
  else
    raise Error, "Unknown marshal type discriminator #{type.chr.inspect} (#{type})"
  end
end

#read_extended_object (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 290


def read_extended_object
  raise NotImplementedError, "Reading Marshal objects of type extended_object is not implemented"
end

#read_false (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 159


def read_false
  Elements::False::FALSE
end

#read_float (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 279


def read_float
  string = read_bytes(read_integer)
  Elements::Float.new(string)
end

#read_hash (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 245


def read_hash
  length = read_integer
  return EMPTY_HASH if length == 0
  pairs = Array.new(length) do
    [read_element, read_element]
  end
  Elements::Hash.new(pairs)
end

#read_hash_with_default_value (private)

Raises:

(NegativeLengthError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 254


def read_hash_with_default_value
  length = read_integer
  raise NegativeLengthError if length < 0
  pairs = Array.new(length) do
    [read_element, read_element]
  end
  default = read_element
  Elements::HashWithDefaultValue.new(pairs, default)
end

#read_header (private)

Raises:

(UnsupportedVersionError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 45


def read_header
  v = @io.read(2)
  raise UnsupportedVersionError, "Unsupported marshal version #{v.bytes.map(&:ord).join(".")}, expected #{Marshal::MAJOR_VERSION}.#{Marshal::MINOR_VERSION}" unless v == MARSHAL_VERSION
end

#read_integer (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 62


def read_integer
  b = read_byte

  case b
  when 0x00
    0
  when 0x01
    read_byte
  when 0x02
    read_byte | (read_byte << 8)
  when 0x03
    read_byte | (read_byte << 8) | (read_byte << 16)
  when 0x04
    read_byte | (read_byte << 8) | (read_byte << 16) | (read_byte << 24)
  when 0xFC
    read_byte | (read_byte << 8) | (read_byte << 16) | (read_byte << 24) | -0x100000000
  when 0xFD
    read_byte | (read_byte << 8) | (read_byte << 16) | -0x1000000
  when 0xFE
    read_byte | (read_byte << 8) | -0x10000
  when 0xFF
    read_byte | -0x100
  else
    signed = (b ^ 128) - 128
    if b >= 128
      signed + 5
    else
      signed - 5
    end
  end
end

#read_module (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 298


def read_module
  raise NotImplementedError, "Reading Marshal objects of type module is not implemented"
end

#read_nil (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 275


def read_nil
  Elements::Nil::NIL
end

#read_object (private)

Raises:

(NegativeLengthError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 264


def read_object
  name = read_element
  object = Elements::Object.new(name)
  length = read_integer
  raise NegativeLengthError if length < 0
  ivars = Array.new(length) do
    [read_element, read_element]
  end
  Elements::WithIvars.new(object, ivars)
end

#read_object_link (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 237


def read_object_link
  offset = read_integer
  OBJECT_LINKS[offset] || Elements::ObjectLink.new(offset)
end

#read_object_with_ivars (private)

Raises:

(NegativeLengthError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 182


def read_object_with_ivars
  object = read_element
  length = read_integer
  raise NegativeLengthError if length < 0
  ivars = Array.new(length) do
    [read_element, read_element]
  end
  Elements::WithIvars.new(object, ivars)
end

#read_regexp (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 310


def read_regexp
  raise NotImplementedError, "Reading Marshal objects of type regexp is not implemented"
end

#read_string (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 148


def read_string
  length = read_integer
  return EMPTY_STRING if length == 0
  str = read_bytes(length)
  Elements::String.new(str)
end

#read_struct (private)

Raises:

(NotImplementedError)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 314


def read_struct
  raise NotImplementedError, "Reading Marshal objects of type struct is not implemented"
end

#read_symbol (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 130


def read_symbol
  len = read_integer
  if len == 1
    byte = read_byte
    if byte == 69 # ?E
      STRING_E_SYMBOL
    else
      Elements::Symbol.new(byte.chr)
    end
  else
    name = read_bytes(len)
    Elements::Symbol.new(name)
  end
end

#read_symbol_link (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 192


def read_symbol_link
  offset = read_integer
  Elements::SymbolLink.new(offset)
end

#read_true (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 155


def read_true
  Elements::True::TRUE
end

#read_user_class (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 318


def read_user_class
  name = read_element
  wrapped_object = read_element
  Elements::UserClass.new(name, wrapped_object)
end

#read_user_defined (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 163


def read_user_defined
  name = read_element
  binary_string = read_bytes(read_integer)
  Elements::UserDefined.new(name, binary_string)
end

#read_user_marshal (private)

[ GitHub ]

# File 'lib/rubygems/safe_marshal/reader.rb', line 197


def read_user_marshal
  name = read_element
  data = read_element
  Elements::UserMarshal.new(name, data)
end

Class: Gem::SafeMarshal::Reader

Constant Summary

Class Method Summary

Instance Method Summary

Constructor Details

.new(io) ⇒ Reader

Instance Method Details

#read!

#read_array (private)

#read_bignum (private)

#read_byte (private)

#read_bytes(n) (private)

#read_class (private)

#read_class_or_module (private)

#read_data (private)

#read_element (private)

#read_extended_object (private)

#read_false (private)

#read_float (private)

#read_hash (private)

#read_hash_with_default_value (private)

#read_header (private)

#read_integer (private)

#read_module (private)

#read_nil (private)

#read_object (private)

#read_object_link (private)

#read_object_with_ivars (private)

#read_regexp (private)

#read_string (private)

#read_struct (private)

#read_symbol (private)

#read_symbol_link (private)

#read_true (private)

#read_user_class (private)

#read_user_defined (private)

#read_user_marshal (private)

.new(io) ⇒ `Reader`