From a427278cc03b14619afaf62b4ab44c3d3e8d1377 Mon Sep 17 00:00:00 2001
From: Andrew Noyes <andrew@weaselab.dev>
Date: Fri, 17 Jul 2026 15:39:56 -0400
Subject: [PATCH] Read until EAGAIN

To prepare for EPOLLET
---
 src/connection.cpp |  2 +-
 src/connection.hpp |  2 +-
 src/server.cpp     | 35 ++++++++++++++++++++++-------------
 3 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/src/connection.cpp b/src/connection.cpp
index fe092e0..1213e87 100644
--- a/src/connection.cpp
+++ b/src/connection.cpp
@@ -153,7 +153,7 @@ void Connection::send_response(ProtocolHandle handle,
   }
 }
 
-int Connection::readBytes(char *buf, size_t buffer_size) {
+int Connection::read_bytes(char *buf, size_t buffer_size) {
   int r;
   for (;;) {
     r = read(fd_, buf, buffer_size);
diff --git a/src/connection.hpp b/src/connection.hpp
index 81903ff..6cb3ab4 100644
--- a/src/connection.hpp
+++ b/src/connection.hpp
@@ -279,7 +279,7 @@ private:
   friend Ref<T> make_ref(Args &&...args);
 
   // Networking interface - only accessible by Server
-  int readBytes(char *buf, size_t buffer_size);
+  int read_bytes(char *buf, size_t buffer_size);
   enum WriteBytesResult {
     Error = 1 << 0,
     Progress = 1 << 1,
diff --git a/src/server.cpp b/src/server.cpp
index ab0036e..657fb58 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -409,21 +409,30 @@ void Server::process_connection_reads(Ref<Connection> &conn, int events) {
     auto buf_size = config_.server.read_buffer_size;
     g_read_buffer.resize(buf_size);
     char *buf = g_read_buffer.data();
-    int r = conn->readBytes(buf, buf_size);
 
-    if (r < 0) {
-      // Error or EOF - connection should be closed
-      close_connection(conn);
-      return;
+    // Once we do EPOLLET we must drain the socket until read returns EAGAIN.
+    for (;;) {
+      int r = conn->read_bytes(buf, buf_size);
+
+      if (r < 0) {
+        // Error or EOF - connection should be closed
+        close_connection(conn);
+        return;
+      }
+
+      if (r == 0) {
+        // No data available (EAGAIN) - read side drained
+        return;
+      }
+
+      // Call handler with connection reference - server retains ownership.
+      handler_.on_data_arrived(std::string_view{buf, size_t(r)}, *conn);
+
+      // The connection may have been closed by the handler; stop reading.
+      if (!conn) {
+        return;
+      }
     }
-
-    if (r == 0) {
-      // No data available (EAGAIN) - skip read processing but continue
-      return;
-    }
-
-    // Call handler with connection reference - server retains ownership
-    handler_.on_data_arrived(std::string_view{buf, size_t(r)}, *conn);
   }
 }