Simplify tagged union

This commit is contained in:
2026-01-23 22:07:53 -05:00
parent 213a01afc8
commit 43f7497424

View File

@@ -1,11 +1,3 @@
/// Type tag for Message union.
/// This is the first value in the actual packet sent over the network.
pub const PacketType = enum(u16) {
relay = 0x003C,
connection = 0x00E9,
_,
};
pub const MessageTypeError = error{ pub const MessageTypeError = error{
NotImplementedSaprusType, NotImplementedSaprusType,
UnknownSaprusType, UnknownSaprusType,
@@ -16,16 +8,18 @@ pub const MessageParseError = MessageTypeError || error{
const message = @This(); const message = @This();
pub const Message = union(PacketType) { pub const Message = union(enum(u16)) {
relay: Message.Relay, relay: Message.Relay = 0x003C,
connection: Message.Connection, connection: Message.Connection = 0x00E9,
_,
pub const Relay = message.Relay; pub const Relay = message.Relay;
pub const Connection = message.Connection; pub const Connection = message.Connection;
pub fn toBytes(self: message.Message, buf: []u8) []u8 { pub fn toBytes(self: message.Message, buf: []u8) []u8 {
return switch (self) { return switch (self) {
inline else => |m| m.toBytes(buf), inline .relay, .connection => |m| m.toBytes(buf),
else => unreachable,
}; };
} }
@@ -36,7 +30,7 @@ pub const relay_dest_len = 4;
pub fn parse(bytes: []const u8) MessageParseError!Message { pub fn parse(bytes: []const u8) MessageParseError!Message {
var in: Reader = .fixed(bytes); var in: Reader = .fixed(bytes);
const @"type" = in.takeEnum(PacketType, .big) catch |err| switch (err) { const @"type" = in.takeEnum(std.meta.Tag(Message), .big) catch |err| switch (err) {
error.InvalidEnumTag => return error.UnknownSaprusType, error.InvalidEnumTag => return error.UnknownSaprusType,
else => return error.InvalidMessage, else => return error.InvalidMessage,
}; };
@@ -124,7 +118,7 @@ const Relay = struct {
/// Asserts that buf is large enough to fit the relay message. /// Asserts that buf is large enough to fit the relay message.
pub fn toBytes(self: Relay, buf: []u8) []u8 { pub fn toBytes(self: Relay, buf: []u8) []u8 {
var out: Writer = .fixed(buf); var out: Writer = .fixed(buf);
out.writeInt(u16, @intFromEnum(PacketType.relay), .big) catch unreachable; out.writeInt(u16, @intFromEnum(Message.relay), .big) catch unreachable;
out.writeInt(u16, @intCast(self.payload.len + 4), .big) catch unreachable; // Length field, but unread. Will switch to checksum out.writeInt(u16, @intCast(self.payload.len + 4), .big) catch unreachable; // Length field, but unread. Will switch to checksum
out.writeAll(&self.dest.bytes) catch unreachable; out.writeAll(&self.dest.bytes) catch unreachable;
out.writeAll(self.payload) catch unreachable; out.writeAll(self.payload) catch unreachable;
@@ -178,7 +172,7 @@ const Connection = struct {
/// Asserts that buf is large enough to fit the connection message. /// Asserts that buf is large enough to fit the connection message.
pub fn toBytes(self: Connection, buf: []u8) []u8 { pub fn toBytes(self: Connection, buf: []u8) []u8 {
var out: Writer = .fixed(buf); var out: Writer = .fixed(buf);
out.writeInt(u16, @intFromEnum(PacketType.connection), .big) catch unreachable; out.writeInt(u16, @intFromEnum(Message.connection), .big) catch unreachable;
out.writeInt(u16, @intCast(self.payload.len + 14), .big) catch unreachable; // Saprus length field, unread. out.writeInt(u16, @intCast(self.payload.len + 14), .big) catch unreachable; // Saprus length field, unread.
out.writeInt(u16, self.src, .big) catch unreachable; out.writeInt(u16, self.src, .big) catch unreachable;
out.writeInt(u16, self.dest, .big) catch unreachable; out.writeInt(u16, self.dest, .big) catch unreachable;