From 2f049101c2601116c29a457f41109328f64bb16d Mon Sep 17 00:00:00 2001
From: Krzosa Karol <krzosa@proton.me>
Date: Thu, 29 Jan 2026 10:30:41 +0100
Subject: [PATCH] Polling and handling connections + messages at the same time

---
 src/b.cpp | 84 +++++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 69 insertions(+), 15 deletions(-)

diff --git a/src/b.cpp b/src/b.cpp
index 226f8a6..9ad3555 100644
--- a/src/b.cpp
+++ b/src/b.cpp
@@ -37,6 +37,25 @@ int wrapped_close_socket(SOCKET socket) {
     return -1;
 }
 
+void set_non_blocking(SOCKET sock) {
+    u_long mode = 1;
+    int err = ioctlsocket(sock, FIONBIO, &mode);
+    if (err != 0) {
+        panicf("server: failed to set nonblocking mode %s", wsa_error());
+    }
+}
+
+void set_no_delay(SOCKET sock) {
+    // Disable Nagle's algorithm, this would combine some of the packets together and these would
+    // get received on server side in one combined buffer. Two stacked 'hello world', the horror!
+    // This only finally worked when I set it on ALL the sockets, including the one in client.
+    int nodelay = 0;
+    int err = setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (char *)&nodelay, sizeof(nodelay));
+    if (err != 0) {
+        panicf("server: failed to setsockopt %s", wsa_error());
+    }
+}
+
 void run_server() {
     struct addrinfo *infos = {};
     struct addrinfo hints = {};
@@ -72,31 +91,62 @@ void run_server() {
         panicf("server: failed to bind to a port!");
     }
     defer { wrapped_close_socket(sock); };
+    set_no_delay(sock);
+    set_non_blocking(sock);
 
     int max_pending_connections = 10;
     err = listen(sock, max_pending_connections);
     if (err != 0) { panicf("server: listen failed: %s", wsa_error()); }
 
-    sockaddr_storage client_sockaddr = {};
-    int sockaddr_len = sizeof(client_sockaddr);
-    SOCKET client_sock = accept(sock, (sockaddr *)&client_sockaddr, &sockaddr_len);
-    if (client_sock == -1) {
-        panicf("server: failed to accept connection %s", wsa_error());
+    WSAPOLLFD pfds[256] = {};
+    int pfd_count = 0;
+    {
+        pfds[pfd_count].fd = sock;
+        pfds[pfd_count].events = POLLIN;
+        pfd_count += 1;
     }
-    defer { wrapped_close_socket(client_sock); };
 
     for (;;) {
-        char buff[1024];
-        int bytes = recv(client_sock, buff, lengthof(buff) - 1, 0);
-        if (bytes == -1) {
-            panicf("server: failed recv %s", wsa_error());
+        int timeout = -1;
+        int poll_count = WSAPoll(pfds, pfd_count, timeout);
+        if (poll_count == -1) {
+            panicf("server: failed to poll %s", wsa_error());
         }
-        debugf("server: %.*s", bytes, buff);
 
-        if (bytes == 4 && buff[0] == 'q' && buff[1] == 'u' && buff[2] == 'i' && buff[3] == 't') {
-            break;
+        for (int i = 0; i < pfd_count; i += 1) {
+            bool ok = pfds[i].revents & (POLLIN | POLLHUP);
+            if (!ok) continue;
+
+            // Handle new connection or receive data
+            if (pfds[i].fd == sock) {
+                sockaddr_storage addr = {};
+                int sockaddr_len = sizeof(addr);
+                SOCKET client_sock = accept(sock, (sockaddr *)&addr, &sockaddr_len);
+                if (client_sock == -1) {
+                    panicf("server: failed to accept connection %s", wsa_error());
+                }
+                set_no_delay(client_sock);
+                pfds[i].fd = client_sock;
+                pfds[i].events = POLLIN;
+                pfds[i].revents = 0;
+                pfd_count += 1;
+
+                debugf("server: new connection from: %s", serialize((sockaddr *)&addr));
+            } else {
+                char buff[1024];
+                int bytes = recv(pfds[i].fd, buff, lengthof(buff) - 1, 0);
+                if (bytes == -1) {
+                    panicf("server: failed recv %s", wsa_error());
+                }
+                debugf("server: %.*s", bytes, buff);
+
+                if (bytes == 4 && buff[0] == 'q' && buff[1] == 'u' && buff[2] == 'i' && buff[3] == 't') {
+                    break;
+                }
+            }
         }
     }
+
     debugf("server: exiting");
 }
 
@@ -134,16 +184,20 @@ void run_client() {
     }
     defer { wrapped_close_socket(sock); };
 
+    set_no_delay(sock);
+
     for (;;) {
         const char *buff = "hello world!";
         int buff_size = (int)strlen(buff);
+        debugf("client: sending %s", buff);
         int bytes = send(sock, buff, buff_size, 0);
+        debugf("bytes sent: %d", bytes);
+
         // bytes can be less then buffer and that needs to be handled
         // that is the remaining amount needs to be sent?
         if (bytes == SOCKET_ERROR) {
             debugf("client: failed to send %s", wsa_error());
         }
-
     }
 
 }
@@ -174,7 +228,7 @@ int main() {
         panicf("Version 2.2 of Winsock not available");
     }
 
-    constexpr int thread_count = 2;
+    constexpr int thread_count = 8;
     HANDLE thread_handles[thread_count] = {};
     DWORD thread_ids[thread_count] = {};
     Thread_Context thread_datas[thread_count] = {};