From f3fe9b60d20b5b2e2a08ec0de0fca506c03f35e7 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Mon, 19 Dec 2022 22:50:01 -0300
Subject: [PATCH] add receive buffers to prevent stuttering

---
 src/main.zig | 38 +++++++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/src/main.zig b/src/main.zig
index dd70aef..1227401 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -47,17 +47,33 @@ pub fn main() !void {
     var to_sock = try network.Socket.create(.ipv4, .udp);
     defer to_sock.close();
 
-    var receive_buffer: [2048]u8 = undefined;
-    while (true) {
-        const reader = from_sock.reader();
-        const received_bytes = try reader.read(&receive_buffer);
-        const bytes = receive_buffer[0..received_bytes];
-        const sent_bytes = try to_sock.sendTo(to, bytes);
-        if (sent_bytes != received_bytes) {
-            logger.warn(
-                "tried to send {d} bytes, actually sent {d}",
-                .{ received_bytes, sent_bytes },
-            );
+    const BUFSIZE = 4;
+    const Buffer = struct {
+        raw_data: [2048]u8,
+        message: []u8,
+    };
+
+    var receive_buffers: [BUFSIZE]Buffer = undefined;
+    var receive_buffer_index: usize = 0;
+
+    const reader = from_sock.reader();
+
+    while (true) : (receive_buffer_index += 1) {
+        const array_index = receive_buffer_index % BUFSIZE;
+        const raw_data = &receive_buffers[array_index].raw_data;
+        const received_bytes = try reader.read(raw_data);
+        receive_buffers[array_index].message = raw_data[0..received_bytes];
+
+        if (receive_buffer_index > BUFSIZE) {
+            const index_to_send = (receive_buffer_index - BUFSIZE - 1) % BUFSIZE;
+            const bytes_to_send = receive_buffers[index_to_send].message;
+            const sent_bytes = try to_sock.sendTo(to, bytes_to_send);
+            if (sent_bytes != received_bytes) {
+                logger.warn(
+                    "tried to send {d} bytes, actually sent {d}",
+                    .{ received_bytes, sent_bytes },
+                );
+            }
         }
     }
 }