From 199d2cb6c2383fba3879af5e8ee7fd7173da72bd Mon Sep 17 00:00:00 2001
From: socec <igorsocec@gmail.com>
Date: Sun, 9 Mar 2014 18:48:04 +0100
Subject: [PATCH] stop crashing server when client disconnects

---
 moxerver.c | 15 +++++++++++++--
 moxerver.h |  1 +
 server.c   |  5 +++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/moxerver.c b/moxerver.c
index 3fee3de..beb1121 100644
--- a/moxerver.c
+++ b/moxerver.c
@@ -1,7 +1,7 @@
 #include "moxerver.h"
 
 
-#define SERVER_WAIT_TIMEOUT 10 /* seconds for select() timeout in server loop */
+#define SERVER_WAIT_TIMEOUT 5 /* seconds for select() timeout in server loop */
 #define PORT_MIN 4001 /* minimum TCP port number */
 #define PORT_MAX 4008 /* maximum TCP port number */
 
@@ -137,7 +137,18 @@ int main(int argc, char *argv[]) {
 			}
 		}
 		if (ret == 0) {
-			fprintf(stderr, "server waiting\n");
+			/* check if client disconnected */
+			/* a disconnected client socket is ready for reading but read returns 0 */
+			if ( (client.socket != -1) && FD_ISSET(client.socket, &read_fds) ) {
+				if (client_read(&client) == 0) {
+					fprintf(stderr, "client %s disconnected\n", client.ip_string);
+					/* close client connection */
+					client_close(&client);
+				}
+			}
+			else {
+				fprintf(stderr, "server waiting\n");
+			}
 		}
 		
 	} /* END while loop */
diff --git a/moxerver.h b/moxerver.h
index 7b6c604..7275df2 100644
--- a/moxerver.h
+++ b/moxerver.h
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <fcntl.h>
 #include <string.h>
 #include <errno.h>
 #include <sys/types.h>
diff --git a/server.c b/server.c
index deb1f5c..881c00e 100644
--- a/server.c
+++ b/server.c
@@ -85,6 +85,11 @@ int server_accept(struct server_t *server, struct client_t *accepted_client) {
 		fprintf(stderr, "[%s:%d] error %d: %s\n", __func__, __LINE__, errno, strerror(errno));
 		return -errno;
 	}
+	/* make client socket non-blocking */
+	if (fcntl(accepted_client->socket, F_SETFL, O_NONBLOCK) == -1) {
+		fprintf(stderr, "[%s:%d] error %d: %s\n", __func__, __LINE__, errno, strerror(errno));
+		return -errno;
+	}
 	
 	/* get client IP address as human readable string */
 	inet_ntop(accepted_client->address.sin_family, &accepted_client->address.sin_addr.s_addr,