Class: Tina4Ultipa::Codec::Reader

Inherits:
Object
  • Object
show all
Defined in:
lib/tina4_ultipa/codec.rb

Overview

Walks a self-describing binary blob, reading little-endian fixed-width ints, length-prefixed strings, and TypedValueEntry composites. Mirrors Python _Reader.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(data) ⇒ Reader

Returns a new instance of Reader.



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# File 'lib/tina4_ultipa/codec.rb', line 203

def initialize(data)
  @d = (data || "".b).dup.force_encoding("BINARY")
  @p = 0
end

Instance Attribute Details

#d ⇒ Object

Returns the value of attribute d.



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# File 'lib/tina4_ultipa/codec.rb', line 201

def d
  @d
end

#p ⇒ Object

Returns the value of attribute p.



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# File 'lib/tina4_ultipa/codec.rb', line 201

def p
  @p
end

Instance Method Details

#props ⇒ Object

uint16 count of (uint16 keyLen + key + TypedValueEntry) property pairs.



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# File 'lib/tina4_ultipa/codec.rb', line 251

def props
  out = {}
  u16.times do
    key = str
    out[key] = tve
  end
  out
end

#str ⇒ Object

uint16 length prefix + that many UTF-8 bytes.



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# File 'lib/tina4_ultipa/codec.rb', line 233

def str
  n = u16
  v = @d.byteslice(@p, n).dup.force_encoding("UTF-8")
  @p += n
  v
end

#tve ⇒ Object

A TypedValueEntry: type u8, isNull u8, len u32, data -> decoded value (nil if null).



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# File 'lib/tina4_ultipa/codec.rb', line 241

def tve
  t = u8
  is_null = u8
  n = u32
  data = @d.byteslice(@p, n)
  @p += n
  is_null.zero? ? Codec.scalar(t, data) : nil
end

#u16 ⇒ Object 



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# File 'lib/tina4_ultipa/codec.rb', line 214

def u16
  v = @d.byteslice(@p, 2).unpack1("S<")
  @p += 2
  v
end

#u32 ⇒ Object 



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# File 'lib/tina4_ultipa/codec.rb', line 220

def u32
  v = @d.byteslice(@p, 4).unpack1("L<")
  @p += 4
  v
end

#u64 ⇒ Object 



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# File 'lib/tina4_ultipa/codec.rb', line 226

def u64
  v = @d.byteslice(@p, 8).unpack1("Q<")
  @p += 8
  v
end

#u8 ⇒ Object 



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# File 'lib/tina4_ultipa/codec.rb', line 208

def u8
  v = @d.getbyte(@p)
  @p += 1
  v
end