Initial: port of pgx to zig (so, pgz)

Starting with message structures, so far we have
startup_message and authentication_ok

1 files changed, 46 insertions, 0 deletions

diff --git a/src/authentication_ok.zig b/src/authentication_ok.zig
new file mode 100644
index 0000000..3c31375
--- /dev/null
+++ b/src/authentication_ok.zig
@@ -0,0 +1,46 @@
+const std = @import("std");
+const ProtocolError = @import("main.zig").ProtocolError;
+const AuthType = @import("main.zig").AuthType;
+const enum_from_int = @import("main.zig").enum_from_int;
+const ClientError = @import("main.zig").ClientError;
+const AuthenticationOk = @This();
+const ByteArrayList = std.ArrayList(u8);
+
+pub const Tag: u8 = 'R';
+
+pub fn read(_: std.mem.Allocator, b: []const u8) !AuthenticationOk {
+    if (b.len != 4) return ProtocolError.InvalidMessageLength;
+
+    const auth_type = enum_from_int(AuthType, std.mem.readIntBig(u32, b[0..4])) orelse return ClientError.UnsupportedAuthType;
+    if (auth_type != AuthType.AuthTypeOk) return ProtocolError.InvalidAuthType;
+    return .{};
+}
+
+pub fn write(_: AuthenticationOk, _: std.mem.Allocator, stream_writer: anytype) !void {
+    try stream_writer.writeByte(Tag);
+    try stream_writer.writeIntBig(u32, 8);
+    try stream_writer.writeIntBig(u32, @intFromEnum(AuthType.AuthTypeOk));
+}
+
+pub fn deinit(_: *AuthenticationOk, _: std.mem.Allocator) void {}
+
+test "round trip" {
+    const allocator = std.testing.allocator;
+    var sm = AuthenticationOk{};
+    defer sm.deinit(allocator);
+
+    var bal = ByteArrayList.init(allocator);
+    defer bal.deinit();
+    try sm.write(allocator, bal.writer());
+
+    var fbs = std.io.fixedBufferStream(bal.items);
+    var reader = fbs.reader();
+    const tag = try reader.readByte();
+    try std.testing.expectEqual(Tag, tag);
+    const len = try reader.readIntBig(u32);
+    const buf = try allocator.alloc(u8, len - 4);
+    defer allocator.free(buf);
+    try reader.readNoEof(buf);
+    var sm2 = try AuthenticationOk.read(allocator, buf);
+    defer sm2.deinit(allocator);
+}