made sockets non-blocking

app.c

@@ -46,7 +46,7 @@ int djstd_entry(Arena *arena, StringList args) {
     if (isServer) {
         println("Starting server on port %d", port);
         Server myserver = serverInit((ServerInitInfo){
-            .concurrentClients=16,
+            .concurrentClients=2,
             .port=port,
             .memory=Megabytes(64),
         });
@@ -54,48 +54,67 @@ int djstd_entry(Arena *arena, StringList args) {
         server = &myserver;
 
         serverListen(&myserver);
-        Socket *client = serverAccept(&myserver);
+        Socket *client1 = serverAccept(&myserver);
+        Socket *client2 = serverAccept(&myserver);
+
+        Forever {
+            string message = s("Hello. You are client 1.\n");
+            socketWrite(client1, message.str, message.length);
+            message = s("Hello. You are client 2.\n");
+            socketWrite(client2, message.str, message.length);
 
-        forever {
             string buf = PushStringFill(arena, 256, 0);
-            uint64 bytesRead = socketRead(client, buf.str, buf.length - 1);
+            uint64 bytesRead = socketRead(client1, buf.str, buf.length - 1);
 
             if (bytesRead > 0) {
                 buf.length = bytesRead;
-                println("Client said: %S", strSplit(arena, s("\n"), buf).data[0]);
-
-                println("Saying goodbye");
-                string message = s("Goodbye\n");
-                socketWrite(client, message.str, message.length);
+                string message = strSplit(arena, s("\n"), buf).data[0];
+                message = strPrintf(arena, "Client 1 said: %S\n", message);
+                println("%S", message);
+                socketWrite(client2, message.str, message.length);
+
+                println("Saying goodbye to everyone");
+                message = s("Goodbye\n");
+                socketWrite(client1, message.str, message.length);
+                socketWrite(client2, message.str, message.length);
                 break;
             }
-            serverClose(&myserver);
         }
 
-        socketClose(client);
+        socketClose(client1);
+        socketClose(client2);
+        serverClose(&myserver);
     } else {
         println("Connecting to socket at %S on port %d", addr, port);
         Socket sock = socketConnect(arena, (SocketConnectInfo){ .address=addr, .port=port });
-        println("CONNECTED");
+        if (sock.closed) {
+            println("Connection error. Closing.");
+        } else {
+            string message;
+            uint64 bytesWritten;
 
-        string message;
-        uint64 bytesWritten;
+            string buf = PushStringFill(arena, 256, 0);
 
-        string buf = PushStringFill(arena, 256, 0);
+            socketRead(&sock, buf.str, buf.length);
+            string messageReceived = strSplit(arena, s("\n"), buf).data[0];
+            println("%S", strPrintf(arena, "Server said: %S", messageReceived));
 
-        forever {
-            message = s("Howdy partner\n");
-            print("Saying: %S", message);
-            bytesWritten = socketWrite(&sock, message.str, message.length);
+            if (strEql(messageReceived, s("Hello. You are client 1."))) {
+                string broadcast =  s("HELLO WORLD!!!!\n");
+                socketWrite(&sock, broadcast.str, broadcast.length);
+            }
 
-            socketRead(&sock, buf.str, buf.length);
-            message = strSplit(arena, s("\n"), buf).data[0];
-            println("Received message: %S", message);
-            if (strEql(message, s("Goodbye"))) {
-                println("Quitting");
-                break;
+            Forever {
+                socketRead(&sock, buf.str, buf.length);
+                messageReceived = strSplit(arena, s("\n"), buf).data[0];
+                println("Server said: %S", messageReceived);
+                if (strEql(messageReceived, s("Goodbye"))) {
+                    println("Quitting");
+                    break;
+                }
             }
         }
+
         socketClose(&sock);
     }
 

core.h

@@ -16,7 +16,7 @@
 #define function static
 #define global static
 #define local_persist static
-#define forever for (;;)
+#define Forever for (;;)
 
 #define DeferLoop(begin_stmnt, end_stmnt) for(int __defer_i = ((begin_stmnt), 0); __defer_i < 1; (++__defer_i, (end_stmnt)))
 

os.h

@@ -33,6 +33,9 @@ struct Address;
 typedef struct SocketHandle SocketHandle;
 struct SocketHandle;
 
+typedef struct ServerEvents ServerEvents;
+struct ServerEvents;
+
 typedef struct Socket Socket;
 struct Socket {
     const Address *address;
@@ -49,6 +52,7 @@ struct Server {
     SocketHandle *handle;
     SocketList clients;
     bool listening;
+    ServerEvents *events;
 };
 
 typedef struct ServerInitInfo ServerInitInfo;

os_linux.c

@@ -8,6 +8,8 @@
 #include "unistd.h" // POSIX Standard
 #include "stdio.h"
 #include "pthread.h"
+#include "fcntl.h"
+#include "sys/epoll.h"
 
 #include "sys/socket.h"
 #include "arpa/inet.h"
@@ -141,9 +143,17 @@ OS_Thread os_createThread(void *(*entry)(void *), void *ctx) {
     return (OS_Thread){ .id=handle };
 }
 
+typedef struct EPollServerEvents EPollServerEvents;
+struct EPollServerEvents {
+    int epollFd;
+};
+
 Server serverInit(ServerInitInfo info) {
     Arena *arena = arenaAlloc(info.memory);
 
+    EPollServerEvents *events = PushStructZero(arena, EPollServerEvents);
+    events->epollFd = epoll_create1(0);
+
     struct sockaddr_in6 *serverAddr = PushStructZero(arena, struct sockaddr_in6);
     serverAddr->sin6_family = AF_INET6;
     serverAddr->sin6_port = htons(info.port);
@@ -156,9 +166,12 @@ Server serverInit(ServerInitInfo info) {
         .listening=false,
         .port=info.port,
         .handle=(SocketHandle *)(uint64)socket(AF_INET6, SOCK_STREAM, 0 /* IPPROTO_TCP */),
+        .events=(ServerEvents *)events,
     };
 
-    int bindErr = bind((int)(uint64)server.handle, (struct sockaddr *)serverAddr, sizeof(*serverAddr));
+    fcntl((uint64)server.handle, F_SETFL, fcntl((uint64)server.handle, F_GETFL, 0) | O_NONBLOCK);
+
+    int bindErr = bind((uint64)server.handle, (struct sockaddr *)serverAddr, sizeof(*serverAddr));
     if (bindErr == -1) {
         // TODO(dledda): handle err
     }
@@ -169,7 +182,7 @@ Server serverInit(ServerInitInfo info) {
 void serverListen(Server *s) {
     int listenErr = listen((uint64)s->handle, s->clients.capacity);
     if (listenErr == -1) {
-        // TODO(dledda): handle err
+        // TODO(dledda): handle err ?
     }
 }
 
@@ -177,19 +190,22 @@ Socket *serverAccept(Server *s) {
     struct sockaddr_in6 *clientAddr = PushStructZero(s->arena, struct sockaddr_in6);
     socklen_t clientAddrLen = sizeof(*clientAddr);
 
-    uint64 clientSock = accept((int)(uint64)s->handle, (struct sockaddr *)clientAddr, &clientAddrLen);
-    if (clientSock == -1) {
-        // TODO(dledda): handle err
+    uint64 clientSockHandle = accept((int)(uint64)s->handle, (struct sockaddr *)clientAddr, &clientAddrLen);
+    if (clientSockHandle == -1) {
+        clientSockHandle = (uint64)NULL;
+    } else {
+        fcntl((uint64)clientSockHandle, F_SETFL, fcntl((uint64)clientSockHandle, F_GETFL, 0) | O_NONBLOCK);
     }
 
     if (s->clients.length < s->clients.capacity) {
         AppendList(&s->clients, ((Socket){
-            .handle=(SocketHandle *)(uint64)clientSock,
+            .handle=(SocketHandle *)(uint64)clientSockHandle,
             .address=(Address *)clientAddr,
         }));
+        return &s->clients.data[s->clients.length - 1];
+    } else {
+        return PushStructZero(s->arena, Socket);
     }
-
-    return &s->clients.data[s->clients.length - 1];
 }
 
 int64 socketRead(Socket *socket, byte *dest, uint64 numBytes) {