net/tap: update netlink error code management

[dpdk.git] / drivers / net / tap / tap_netlink.c

diff --git a/drivers/net/tap/tap_netlink.c b/drivers/net/tap/tap_netlink.c
index 6de896a..ee92e2e 100644 (file)
--- a/drivers/net/tap/tap_netlink.c
+++ b/drivers/net/tap/tap_netlink.c
@@ -159,7 +159,7 @@ nl_send(int nlsk_fd, struct nlmsghdr *nh)
  *   The netlink socket file descriptor used for communication.
  *
  * @return
- *   0 on success, -1 otherwise.
+ *   0 on success, -1 otherwise with errno set.
  */
 int
 nl_recv_ack(int nlsk_fd)
@@ -179,14 +179,13 @@ nl_recv_ack(int nlsk_fd)
  *   Custom arguments for the callback.
  *
  * @return
- *   0 on success, -1 otherwise.
+ *   0 on success, -1 otherwise with errno set.
  */
 int
 nl_recv(int nlsk_fd, int (*cb)(struct nlmsghdr *, void *arg), void *arg)
 {
        /* man 7 netlink EXAMPLE */
        struct sockaddr_nl sa;
-       struct nlmsghdr *nh;
        char buf[BUF_SIZE];
        struct iovec iov = {
                .iov_base = buf,
@@ -196,49 +195,43 @@ nl_recv(int nlsk_fd, int (*cb)(struct nlmsghdr *, void *arg), void *arg)
                .msg_name = &sa,
                .msg_namelen = sizeof(sa),
                .msg_iov = &iov,
+               /* One message at a time */
                .msg_iovlen = 1,
        };
-       int recv_bytes = 0, done = 0, multipart = 0, error = 0;
+       int multipart = 0;
+       int ret = 0;
 
-read:
-       recv_bytes = recvmsg(nlsk_fd, &msg, 0);
-       if (recv_bytes < 0)
-               return -1;
-       for (nh = (struct nlmsghdr *)buf;
-            NLMSG_OK(nh, (unsigned int)recv_bytes);
-            nh = NLMSG_NEXT(nh, recv_bytes)) {
-               /*
-                * Multi-part messages and their following DONE message have the
-                * NLM_F_MULTI flag set. Make note, in order to read the DONE
-                * message afterwards.
-                */
-               if (nh->nlmsg_flags & NLM_F_MULTI)
-                       multipart = 1;
-               if (nh->nlmsg_type == NLMSG_ERROR) {
-                       struct nlmsgerr *err_data = NLMSG_DATA(nh);
+       do {
+               struct nlmsghdr *nh;
+               int recv_bytes = 0;
+
+               recv_bytes = recvmsg(nlsk_fd, &msg, 0);
+               if (recv_bytes < 0)
+                       return -1;
+               for (nh = (struct nlmsghdr *)buf;
+                    NLMSG_OK(nh, (unsigned int)recv_bytes);
+                    nh = NLMSG_NEXT(nh, recv_bytes)) {
+                       if (nh->nlmsg_type == NLMSG_ERROR) {
+                               struct nlmsgerr *err_data = NLMSG_DATA(nh);
 
-                       if (err_data->error == 0)
-                               RTE_LOG(DEBUG, PMD, "%s() ack message recvd\n",
-                                       __func__);
-                       else {
-                               RTE_LOG(DEBUG, PMD,
-                                       "%s() error message recvd\n", __func__);
-                               error = 1;
+                               if (err_data->error < 0) {
+                                       errno = -err_data->error;
+                                       return -1;
+                               }
+                               /* Ack message. */
+                               return 0;
                        }
+                       /* Multi-part msgs and their trailing DONE message. */
+                       if (nh->nlmsg_flags & NLM_F_MULTI) {
+                               if (nh->nlmsg_type == NLMSG_DONE)
+                                       return 0;
+                               multipart = 1;
+                       }
+                       if (cb)
+                               ret = cb(nh, arg);
                }
-               /* The end of multipart message. */
-               if (nh->nlmsg_type == NLMSG_DONE)
-                       /* No need to call the callback for a DONE message. */
-                       done = 1;
-               else if (cb)
-                       if (cb(nh, arg) < 0)
-                               error = 1;
-       }
-       if (multipart && !done)
-               goto read;
-       if (error)
-               return -1;
-       return 0;
+       } while (multipart);
+       return ret;
 }
 
 /**