Cleanup obsolete code

Refs #431

app/src/main/jni/netguard/netguard.h

@@ -413,8 +413,6 @@ int open_tcp_socket(const struct arguments *args,
 
 int32_t get_local_port(const int sock);
 
-int is_valid_fd(const int fd);
-
 int write_syn_ack(const struct arguments *args, struct tcp_session *cur);
 
 int write_ack(const struct arguments *args, struct tcp_session *cur);

app/src/main/jni/netguard/session.c

@@ -126,7 +126,7 @@ void *handle_events(void *a) {
     while (!stopping) {
         log_android(ANDROID_LOG_DEBUG, "Loop thread %x", thread_id);
 
-        // Count/check sessions
+        // Count sessions
         int isessions = 0;
         int usessions = 0;
         int tsessions = 0;
@@ -208,20 +208,6 @@ void *handle_events(void *a) {
                                 "epoll interrupted tun %d thread %x", args->tun, thread_id);
                     continue;
                 }
-            } else if (errno == EBADF) {
-                if (is_valid_fd(args->tun)) {
-                    log_android(ANDROID_LOG_ERROR, "epoll error %d: %s", errno, strerror(errno));
-                    report_exit(args, "epoll error %d: %s", errno, strerror(errno));
-                    break;
-                }
-                else {
-                    log_android(ANDROID_LOG_ERROR,
-                                "tun socket %d epoll error %d: %s",
-                                args->tun, errno, strerror(errno));
-                    report_exit(args, "tun socket %d epoll error %d: %s",
-                                args->tun, errno, strerror(errno));
-                    break;
-                }
             } else {
                 log_android(ANDROID_LOG_ERROR,
                             "epoll tun %d thread %x error %d: %s",

app/src/main/jni/netguard/util.c

@@ -152,7 +152,3 @@ int32_t get_local_port(const int sock) {
         return ntohs(sin.sin_port);
 }
 
-int is_valid_fd(const int fd) {
-    return fcntl(fd, F_GETFL) != -1 || errno != EBADF;
-}
-