multiple packet types. code quality is declining steadily

1 files changed, 57 insertions, 9 deletions

diff --git a/packet_reader/packet_reader.ha b/packet_reader/packet_reader.ha
index 43b85d1..9cae444 100644
--- a/packet_reader/packet_reader.ha
+++ b/packet_reader/packet_reader.ha
@@ -1,24 +1,33 @@
 use io;
 use fmt;
+use endian;
+use drawing;
 
-export type packet = []u8;
-def PCKSZ: size = 8;
+export type error = !str;
 
 export type packet_reader = struct {
-	buf: [256]u8,
+	buf: []u8,
 	good: []u8,
 };
 
 export fn new() packet_reader = {
 	let pr = packet_reader {
-		buf = [0...],
+		buf = alloc([0...],512*512*4*2), // ehhh
 		...
 	};
 	pr.good = pr.buf[0..0];
 	return pr;
+};
 
+export type packet_type = enum u8 {
+	DRAW_OP,
+	SEND_CHUNK,
 };
 
+export type packet_drawop = drawing::op;
+export type packet_sendchunk = []u32;
+export type packet = (packet_drawop | packet_sendchunk);
+
 // call when input is ready. could block otherwise
 export fn read(pr: *packet_reader, sock: io::handle) (void | io::error | io::EOF) = {
 	const remaining_amt = len(pr.good);
@@ -39,14 +48,53 @@ export fn read(pr: *packet_reader, sock: io::handle) (void | io::error | io::EOF
 	fmt::printfln("now {} bytes in buffer",total_amt)!;
 };
 
+// packet format:
+// u32 size
+// u32 type
+// [size-8]u8 data...
+// size includes size of header (size and type fields)
 
-export fn next(pr: *packet_reader) (packet | done) = {
+export fn next(pr: *packet_reader) (packet | done | error) = {
 	// either parse a full packet out of the front of good,
 	// move good along that many bytes,
 	// and return the packet,
 	// or, ascertain there is no full packet, and return done
-	if (len(pr.good) < PCKSZ) return done;
-	const packet_bytes = pr.good[..PCKSZ];
-	pr.good = pr.good[PCKSZ..];
-	return packet_bytes;
+	if (len(pr.good) < size(u32)) return done;
+	const packet_len = endian::legetu32(pr.good[0..4]);
+	if (packet_len < 8) return "packet size field too small": error;
+	if (len(pr.good) < packet_len) return done;
+
+	const packet_bytes = pr.good[..packet_len];
+	pr.good = pr.good[packet_len..];
+
+	const ty = endian::legetu32(packet_bytes[4..8]): packet_type;
+	switch (ty) {
+	case packet_type::DRAW_OP =>
+		const op = drawing::deser_op(packet_bytes[8..]);
+		return op: packet_drawop;
+	case packet_type::SEND_CHUNK =>
+		// in an ideal world we would need no copies
+		const totally_necessary_copy = alloc(packet_bytes[8..]...);
+		return totally_necessary_copy: packet_sendchunk;
+	};
+};
+
+export fn send_raw(sock: io::file, ty: packet_type, data: []u8) (void | io::error) = {
+	// ehh
+	const header: [8]u8 = [0...];
+	endian::leputu32(header[0..4], 8u32 + len(data):u32);
+	endian::leputu32(header[4..8], ty);
+	io::writeall(sock, header)?;
+	io::writeall(sock, data)?;
+};
+
+export fn send(sock: io::file, packet: packet) (void | io::error) = {
+	match (packet) {
+	case let op: packet_drawop =>
+		const ser_op = drawing::ser_op(op);
+		defer free(ser_op);
+		send_raw(sock, packet_type::DRAW_OP, ser_op)?;
+	case let chunkdata: packet_sendchunk =>
+		abort("not implemented sendchunk yet");
+	};
 };