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-rw-r--r--src/saprus_message.zig211
1 files changed, 0 insertions, 211 deletions
diff --git a/src/saprus_message.zig b/src/saprus_message.zig
deleted file mode 100644
index 3d47f66..0000000
--- a/src/saprus_message.zig
+++ /dev/null
@@ -1,211 +0,0 @@
-const base64Enc = std.base64.Base64Encoder.init(std.base64.standard_alphabet_chars, '=');
-const base64Dec = std.base64.Base64Decoder.init(std.base64.standard_alphabet_chars, '=');
-
-/// Type tag for SaprusMessage union.
-/// This is the first value in the actual packet sent over the network.
-pub const SaprusPacketType = enum(u16) {
- relay = 0x003C,
- file_transfer = 0x8888,
- connection = 0x00E9,
- _,
-};
-
-/// Reserved option values.
-/// Currently unused.
-pub const SaprusConnectionOptions = packed struct(u8) {
- opt1: bool = false,
- opt2: bool = false,
- opt3: bool = false,
- opt4: bool = false,
- opt5: bool = false,
- opt6: bool = false,
- opt7: bool = false,
- opt8: bool = false,
-};
-
-pub const SaprusError = error{
- NotImplementedSaprusType,
- UnknownSaprusType,
-};
-
-/// All Saprus messages
-pub const SaprusMessage = union(SaprusPacketType) {
- pub const Relay = struct {
- pub const Header = packed struct {
- dest: @Vector(4, u8),
- };
- header: Header,
- payload: []const u8,
- };
- pub const Connection = struct {
- pub const Header = packed struct {
- src_port: u16, // random number > 1024
- dest_port: u16, // random number > 1024
- seq_num: u32 = 0,
- msg_id: u32 = 0,
- reserved: u8 = 0,
- options: SaprusConnectionOptions = .{},
- };
- header: Header,
- payload: []const u8,
- };
- relay: Relay,
- file_transfer: void, // unimplemented
- connection: Connection,
-
- /// Should be called for any SaprusMessage that was declared using a function that you pass an allocator to.
- pub fn deinit(self: SaprusMessage, allocator: Allocator) void {
- switch (self) {
- .relay => |r| allocator.free(r.payload),
- .connection => |c| allocator.free(c.payload),
- else => unreachable,
- }
- }
-
- fn toBytesAux(
- header: anytype,
- payload: []const u8,
- buf: *std.ArrayList(u8),
- allocator: Allocator,
- ) !void {
- const Header = @TypeOf(header);
- // Create a growable string to store the base64 bytes in.
- // Doing this first so I can use the length of the encoded bytes for the length field.
- var payload_list = std.ArrayList(u8).init(allocator);
- defer payload_list.deinit();
- const buf_w = payload_list.writer();
-
- // Write the payload bytes as base64 to the growable string.
- try base64Enc.encodeWriter(buf_w, payload);
-
- // At this point, payload_list contains the base64 encoded payload.
-
- // Add the payload length to the output buf.
- try buf.*.appendSlice(
- asBytes(&nativeToBig(u16, @intCast(payload_list.items.len + @bitSizeOf(Header) / 8))),
- );
-
- // Add the header bytes to the output buf.
- var header_buf: [@sizeOf(Header)]u8 = undefined;
- var header_buf_stream = std.io.fixedBufferStream(&header_buf);
- try header_buf_stream.writer().writeStructEndian(header, .big);
- // Add the exact number of bits in the header without padding.
- try buf.*.appendSlice(header_buf[0 .. @bitSizeOf(Header) / 8]);
-
- try buf.*.appendSlice(payload_list.items);
- }
-
- /// Caller is responsible for freeing the returned bytes.
- pub fn toBytes(self: SaprusMessage, allocator: Allocator) ![]u8 {
- // Create a growable list of bytes to store the output in.
- var buf = std.ArrayList(u8).init(allocator);
- errdefer buf.deinit();
-
- // Start with writing the message type, which is the first 16 bits of every Saprus message.
- try buf.appendSlice(asBytes(&nativeToBig(u16, @intFromEnum(self))));
-
- // Write the proper header and payload for the given packet type.
- switch (self) {
- .relay => |r| try toBytesAux(r.header, r.payload, &buf, allocator),
- .connection => |c| try toBytesAux(c.header, c.payload, &buf, allocator),
- .file_transfer => return SaprusError.NotImplementedSaprusType,
- }
-
- // Collect the growable list as a slice and return it.
- return buf.toOwnedSlice();
- }
-
- fn fromBytesAux(
- comptime packet: SaprusPacketType,
- len: u16,
- r: std.io.FixedBufferStream([]const u8).Reader,
- allocator: Allocator,
- ) !SaprusMessage {
- const Header = @field(@FieldType(SaprusMessage, @tagName(packet)), "Header");
-
- // Read the header for the current message type.
- var header_bytes: [@sizeOf(Header)]u8 = undefined;
- _ = try r.read(header_bytes[0 .. @bitSizeOf(Header) / 8]);
- var header_stream = std.io.fixedBufferStream(&header_bytes);
- const header = try header_stream.reader().readStructEndian(Header, .big);
-
- // Read the base64 bytes into a list to be able to call the decoder on it.
- const payload_buf = try allocator.alloc(u8, len - @bitSizeOf(Header) / 8);
- defer allocator.free(payload_buf);
- _ = try r.readAll(payload_buf);
-
- // Create a buffer to store the payload in, and decode the base64 bytes into the payload field.
- const payload = try allocator.alloc(u8, try base64Dec.calcSizeForSlice(payload_buf));
- try base64Dec.decode(payload, payload_buf);
-
- // Return the type of SaprusMessage specified by the `packet` argument.
- return @unionInit(SaprusMessage, @tagName(packet), .{
- .header = header,
- .payload = payload,
- });
- }
-
- /// Caller is responsible for calling .deinit on the returned value.
- pub fn fromBytes(bytes: []const u8, allocator: Allocator) !SaprusMessage {
- var s = std.io.fixedBufferStream(bytes);
- const r = s.reader();
-
- // Read packet type
- const packet_type = @as(SaprusPacketType, @enumFromInt(try r.readInt(u16, .big)));
-
- // Read the length of the header + base64 encoded payload.
- const len = try r.readInt(u16, .big);
-
- switch (packet_type) {
- .relay => return fromBytesAux(.relay, len, r, allocator),
- .connection => return fromBytesAux(.connection, len, r, allocator),
- .file_transfer => return SaprusError.NotImplementedSaprusType,
- else => return SaprusError.UnknownSaprusType,
- }
- }
-};
-
-const std = @import("std");
-const Allocator = std.mem.Allocator;
-
-const asBytes = std.mem.asBytes;
-const nativeToBig = std.mem.nativeToBig;
-
-test "Round trip Relay toBytes and fromBytes" {
- const gpa = std.testing.allocator;
- const msg = SaprusMessage{
- .relay = .{
- .header = .{ .dest = .{ 255, 255, 255, 255 } },
- .payload = "Hello darkness my old friend",
- },
- };
-
- const to_bytes = try msg.toBytes(gpa);
- defer gpa.free(to_bytes);
-
- const from_bytes = try SaprusMessage.fromBytes(to_bytes, gpa);
- defer from_bytes.deinit(gpa);
-
- try std.testing.expectEqualDeep(msg, from_bytes);
-}
-
-test "Round trip Connection toBytes and fromBytes" {
- const gpa = std.testing.allocator;
- const msg = SaprusMessage{
- .connection = .{
- .header = .{
- .src_port = 0,
- .dest_port = 0,
- },
- .payload = "Hello darkness my old friend",
- },
- };
-
- const to_bytes = try msg.toBytes(gpa);
- defer gpa.free(to_bytes);
-
- const from_bytes = try SaprusMessage.fromBytes(to_bytes, gpa);
- defer from_bytes.deinit(gpa);
-
- try std.testing.expectEqualDeep(msg, from_bytes);
-}