Class: Hornetseye::Malloc

Inherits:

Object

• Object
• Hornetseye::Malloc

show all

Defined in:

lib/malloc_ext.rb

Overview

Instance Attribute Summary (collapse)

• - (Integer) size readonly

  Number of bytes allocated.

Class Method Summary (collapse)

• + (Malloc) new(size)

  Create new Malloc object.

Instance Method Summary (collapse)

• - (Malloc) +(offset)

  Operator for doing pointer arithmetic.

• - (Malloc) dup

  Duplicate object.

• - (Object) export

  Read complete data.

• - (String) inspect

  Display information about this object.

• - (String) read(length)

  Read data from memory.

• - (String) to_s

  Display information about this object.

• - (String) write(data)

  Write data to memory.

m = Malloc.new 32
m.size
# 32
( m + 8 ).size
# 24

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# File 'lib/malloc_ext.rb', line 75

def size
  @size
end

m = Malloc.new 32
# Malloc(32)

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# File 'lib/malloc_ext.rb', line 55

def new( size )
  retval = orig_new size
  retval.instance_eval { @size = size }
  retval
end

m = Malloc.new 4
# Malloc(4)
m.write 'abcd'
n = m + 2
# Malloc(2)
n.read 2
# "cd"

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# File 'lib/malloc_ext.rb', line 140

def +( offset )
  if offset > @size
    raise "Offset must not be more than #{@size} (but was #{offset})"
  end
  mark, size = self, @size - offset
  retval = orig_plus offset
  retval.instance_eval { @mark, @size = mark, size }
  retval
end

m = Malloc.new 3
m.write 'aaa'
n = m.dup
n.write 'bbb'
m.read 3
"aaa"

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# File 'lib/malloc_ext.rb', line 99

def dup
  retval = Malloc.new @size
  retval.write self
  retval
end

m = Malloc.new 3
m.write 'abc'
m.export
"abc"

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# File 'lib/malloc_ext.rb', line 123

def export
  read @size
end

Malloc.new( 8 ).inspect
"Malloc(8)"

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# File 'lib/malloc_ext.rb', line 84

def inspect
  "Malloc(#{@size})"
end

m = Malloc.new 4
# Malloc(4)
m.write 'abcd'
m.read 2
# "ab"

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# File 'lib/malloc_ext.rb', line 166

def read( length )
  raise "Only #{@size} bytes of memory left to read " +
    "(illegal attempt to read #{length} bytes)" if length > @size
  orig_read length
end

Malloc.new( 8 ).to_s
"Malloc(8)"

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# File 'lib/malloc_ext.rb', line 112

def to_s
  inspect
end

m = Malloc.new 4
# Malloc(4)
m.write 'abcd'
m.read 2
# "ab"

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# File 'lib/malloc_ext.rb', line 187

def write( data )
  if data.is_a? Malloc
    if data.size > @size
      raise "Must not write more than #{@size} bytes of memory " +
        "(illegal attempt to write #{data.size} bytes)"
    end
    orig_write data, data.size
  else
    if data.bytesize > @size
      raise "Must not write more than #{@size} bytes of memory " +
        "(illegal attempt to write #{data.bytesize} bytes)"
    end
    orig_write data
  end
end