76 lines
1.6 KiB
Crystal
76 lines
1.6 KiB
Crystal
# TODO: tests.
|
|
|
|
# Serialization (and deserialization) doesn't refer to IPC format.
|
|
# IPC serialization format: 'length + value'
|
|
# IPCMessage serialization: 'value'
|
|
# 'Value' is:
|
|
# - simply the message payload for UntypedMessage
|
|
# - type (u8) + payload for TypedMessage
|
|
module IPCMessage
|
|
class UntypedMessage
|
|
property payload : Bytes
|
|
|
|
def initialize(string : String)
|
|
@payload = Bytes.new string.to_unsafe, string.size
|
|
end
|
|
|
|
def initialize(@payload)
|
|
end
|
|
|
|
def self.deserialize(payload : Bytes) : UntypedMessage
|
|
IPCMessage::UntypedMessage.new payload
|
|
end
|
|
|
|
def serialize
|
|
@payload
|
|
end
|
|
end
|
|
|
|
# WARNING: you can only have up to 256 types.
|
|
class TypedMessage < UntypedMessage
|
|
property type : UInt8? = nil
|
|
|
|
def initialize(@type, string : String)
|
|
super string
|
|
end
|
|
|
|
def initialize(@type, payload)
|
|
super payload
|
|
end
|
|
|
|
def initialize(payload)
|
|
super payload
|
|
end
|
|
|
|
def self.deserialize(bytes : Bytes) : TypedMessage?
|
|
if bytes.size == 0
|
|
nil
|
|
else
|
|
type = bytes[0]
|
|
IPCMessage::TypedMessage.new type, bytes[1..]
|
|
end
|
|
end
|
|
|
|
def serialize
|
|
bytes = Bytes.new(1 + @payload.size)
|
|
type = @type
|
|
bytes[0] = type.nil? ? 0.to_u8 : type
|
|
bytes[1..].copy_from @payload
|
|
bytes
|
|
end
|
|
end
|
|
end
|
|
|
|
# Send both typed and untyped messages.
|
|
class IPC
|
|
def schedule(fd : Int32, m : (IPCMessage::TypedMessage | IPCMessage::UntypedMessage))
|
|
payload = m.serialize
|
|
schedule fd, payload
|
|
end
|
|
|
|
def write(fd : Int32, m : (IPCMessage::TypedMessage | IPCMessage::UntypedMessage))
|
|
payload = m.serialize
|
|
write fd, payload
|
|
end
|
|
end
|