1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198
|
# encoding: binary
require "amq/endianness"
require "amq/protocol/type_constants"
require "amq/protocol/float_32bit"
module AMQ
module Protocol
class TableValueDecoder
#
# Behaviors
#
include TypeConstants
#
# API
#
def self.decode_array(data, initial_offset)
array_length = data.slice(initial_offset, 4).unpack(PACK_UINT32).first
ary = Array.new
offset = initial_offset + 4
while offset <= (initial_offset + array_length)
type, offset = decode_value_type(data, offset)
i = case type
when TYPE_STRING
v, offset = decode_string(data, offset)
v
when TYPE_BYTE_ARRAY
# Ruby doesn't have a direct counterpart to
# ByteBuffer or byte[], so using a string feels
# more appropriate than an array of fixnums
v, offset = decode_string(data, offset)
v
when TYPE_INTEGER
v, offset = decode_integer(data, offset)
v
when TYPE_DECIMAL
v, offset = decode_big_decimal(data, offset)
v
when TYPE_TIME
v, offset = decode_time(data, offset)
v
when TYPE_HASH
v, offset = decode_hash(data, offset)
v
when TYPE_BOOLEAN
v, offset = decode_boolean(data, offset)
v
when TYPE_BYTE then
v, offset = decode_byte(data, offset)
v
when TYPE_SIGNED_16BIT then
v, offset = decode_short(data, offset)
v
when TYPE_SIGNED_64BIT then
v, offset = decode_long(data, offset)
v
when TYPE_32BIT_FLOAT then
v, offset = decode_32bit_float(data, offset)
v
when TYPE_64BIT_FLOAT then
v, offset = decode_64bit_float(data, offset)
v
when TYPE_VOID
nil
when TYPE_ARRAY
v, offset = TableValueDecoder.decode_array(data, offset)
v
else
raise ArgumentError.new("unsupported type in a table value: #{type.inspect}, do not know how to decode!")
end
ary << i
end
[ary, initial_offset + array_length + 4]
end # self.decode_array(data, initial_offset)
def self.decode_string(data, offset)
length = data.slice(offset, 4).unpack(PACK_UINT32).first
offset += 4
v = data.slice(offset, length)
offset += length
[v, offset]
end # self.decode_string(data, offset)
def self.decode_integer(data, offset)
v = data.slice(offset, 4).unpack(PACK_UINT32).first
offset += 4
[v, offset]
end # self.decode_integer(data, offset)
if AMQ::Endianness.big_endian?
def self.decode_long(data, offset)
v = data.slice(offset, 8).unpack(PACK_INT64)
offset += 8
[v, offset]
end
else
def self.decode_long(data, offset)
slice = data.slice(offset, 8).bytes.to_a.reverse.map(&:chr).join
v = slice.unpack(PACK_INT64).first
offset += 8
[v, offset]
end
end
def self.decode_big_decimal(data, offset)
decimals, raw = data.slice(offset, 5).unpack(PACK_UCHAR_UINT32)
offset += 5
v = BigDecimal(raw.to_s) * (BigDecimal(TEN) ** -decimals)
[v, offset]
end # self.decode_big_decimal(data, offset)
def self.decode_time(data, offset)
timestamp = data.slice(offset, 8).unpack(PACK_UINT64_BE).last
v = Time.at(timestamp)
offset += 8
[v, offset]
end # self.decode_time(data, offset)
def self.decode_boolean(data, offset)
integer = data.slice(offset, 2).unpack(PACK_CHAR).first # 0 or 1
offset += 1
[(integer == 1), offset]
end # self.decode_boolean(data, offset)
def self.decode_32bit_float(data, offset)
v = data.slice(offset, 4).unpack(PACK_32BIT_FLOAT).first
offset += 4
[v, offset]
end # self.decode_32bit_float(data, offset)
def self.decode_64bit_float(data, offset)
v = data.slice(offset, 8).unpack(PACK_64BIT_FLOAT).first
offset += 8
[v, offset]
end # self.decode_64bit_float(data, offset)
def self.decode_value_type(data, offset)
[data.slice(offset, 1), offset + 1]
end # self.decode_value_type(data, offset)
def self.decode_hash(data, offset)
length = data.slice(offset, 4).unpack(PACK_UINT32).first
v = Table.decode(data.slice(offset, length + 4))
offset += 4 + length
[v, offset]
end # self.decode_hash(data, offset)
# Decodes/Converts a byte value from the data at the provided offset.
#
# @param [Array] data - A big-endian ordered array of bytes.
# @param [Fixnum] offset - The offset which bytes the byte is consumed.
# @return [Array] - The Fixnum value and new offset pair.
def self.decode_byte(data, offset)
[data.slice(offset, 1).unpack(PACK_CHAR).first, offset += 1]
end
def self.decode_short(data, offset)
v = AMQ::Hacks.unpack_int16_big_endian(data.slice(offset, 2)).first
offset += 2
[v, offset]
end
end # TableValueDecoder
end # Protocol
end # AMQ
|