usock: add helper waiting for socket to be ready

[project/libubox.git] / usock.c

diff --git a/usock.c b/usock.c
index 6458151c02f91e2e8bbde46f04b52005b3d5982d..db1ddcee650d432fe0a30ace890223f3e6adfa3b 100644 (file)
--- a/usock.c
+++ b/usock.c
@@ -1,13 +1,33 @@
+/*
+ * usock - socket helper functions
+ *
+ * Copyright (C) 2010 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2011-2012 Felix Fietkau <nbd@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <netdb.h>
+#include <poll.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <string.h>
 #include <stdbool.h>
+#include <stdio.h>
 
 #include "usock.h"
 
@@ -83,6 +103,18 @@ static int usock_inet(int type, const char *host, const char *service, int sockt
        return sock;
 }
 
+const char *usock_port(int port)
+{
+       static char buffer[sizeof("65535\0")];
+
+       if (port < 0 || port > 65535)
+               return NULL;
+
+       snprintf(buffer, sizeof(buffer), "%u", port);
+
+       return buffer;
+}
+
 int usock(int type, const char *host, const char *service) {
        int socktype = ((type & 0xff) == USOCK_TCP) ? SOCK_STREAM : SOCK_DGRAM;
        bool server = !!(type & USOCK_SERVER);
@@ -99,3 +131,29 @@ int usock(int type, const char *host, const char *service) {
        usock_set_flags(sock, type);
        return sock;
 }
+
+int usock_wait_ready(int fd, int msecs) {
+       struct pollfd fds[1];
+       int res;
+
+       fds[0].fd = fd;
+       fds[0].events = POLLOUT;
+
+       res = poll(fds, 1, msecs);
+       if (res < 0) {
+               return errno;
+       } else if (res == 0) {
+               return -ETIMEDOUT;
+       } else {
+               int err = 0;
+               socklen_t optlen = sizeof(err);
+
+               res = getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &optlen);
+               if (res)
+                       return errno;
+               if (err)
+                       return err;
+       }
+
+       return 0;
+}