Added errno generation in VMCI failures where errno was not set (#1049)

We have some cases when protocol failed (e.g. EOF from client, or whatever).
THis is indicated with 0 lenght returned , but errno was no set because  it's considered success.
This makes it inconsistent with CGO (and maybe others) who rely on errno to form "err" part of the return value

esx_service/vmci/connection_types.h

@@ -28,6 +28,13 @@
 // First non privileged port
 #define START_NON_PRIVILEGED_PORT 1024
 
+/*
+ * Check and set errno helper
+ * Useful when send/recv gets us less than we wanted, and we want to set errno
+ * for the caller to know about the protocol Issue
+ */
+ #define CHECK_ERRNO(_ret)  {if (_ret >= 0 && errno == 0) { errno = EBADMSG; }}
+
 /*
  * This function acquires and returns address family for vSockets.
  * On failure returns -1 an sets errno (if not set by VMCISock_GetAFValue ())

esx_service/vmci/vmci_client.c

@@ -251,16 +251,19 @@ vsock_get_reply(be_sock_id *s, be_request *r, be_answer* a)
    b = MAGIC;
    ret = send(s->sock_id, &b, sizeof b, 0);
    if (ret == -1 || ret != sizeof b) {
+      CHECK_ERRNO(ret);
       return CONN_FAILURE;
    }
 
    ret = send(s->sock_id, &r->mlen, sizeof r->mlen, 0);
    if (ret == -1 || ret != sizeof r->mlen) {
+      CHECK_ERRNO(ret);
       return CONN_FAILURE;
    }
 
    ret = send(s->sock_id, r->msg, r->mlen, 0);
    if (ret == -1 || ret != r->mlen) {
+      CHECK_ERRNO(ret);
       return CONN_FAILURE;
    }
 
@@ -269,6 +272,7 @@ vsock_get_reply(be_sock_id *s, be_request *r, be_answer* a)
    b = 0;
    ret = recv(s->sock_id, &b, sizeof b, 0);
    if (ret == -1 || ret != sizeof b ) {
+      CHECK_ERRNO(ret);
       snprintf(a->errBuf, ERR_BUF_LEN, "Failed to receive magic data: received %d expected %d bytes\n",
                ret, sizeof b);
       return CONN_FAILURE;
@@ -282,6 +286,7 @@ vsock_get_reply(be_sock_id *s, be_request *r, be_answer* a)
    // length
    ret = recv(s->sock_id, &b, sizeof b, 0);
    if (ret == -1 || ret != sizeof b) {
+      CHECK_ERRNO(ret);
       snprintf(a->errBuf, ERR_BUF_LEN, "Failed to receive data len : ret %d (%s)\n",
                ret, strerror(errno));
       return CONN_FAILURE;
@@ -299,6 +304,7 @@ vsock_get_reply(be_sock_id *s, be_request *r, be_answer* a)
    if (ret == -1 || ret != b) {
       free(a->buf);
       a->buf = NULL;
+      CHECK_ERRNO(ret);
       snprintf(a->errBuf, ERR_BUF_LEN, "Failed to receive message data: received %d expected %d\n",
                ret, b);
       return CONN_FAILURE;

esx_service/vmci/vmci_server.c

@@ -154,6 +154,7 @@ vmci_get_one_op(const int s,    // socket to listen on
                ret, strerror(errno), b, MAGIC);
       close(client_socket);
       errno = saved_errno;
+      CHECK_ERRNO(ret);
       return CONN_FAILURE;
    }
 
@@ -184,6 +185,7 @@ vmci_get_one_op(const int s,    // socket to listen on
                ret, strerror(errno), b);
       close(client_socket);
       errno = saved_errno;
+      CHECK_ERRNO(ret);
       return CONN_FAILURE;
    }
    // do protocol sanity check
@@ -255,6 +257,7 @@ vmci_reply(const int client_socket,      // socket to use
 failed:
    close(client_socket);
    errno = saved_errno;
+   CHECK_ERRNO(ret);
    return CONN_FAILURE;
 }
 

vmdk_plugin/utils/refcount/refcnt.go

@@ -286,8 +286,8 @@ func (r RefCountsMap) discoverAndSync(c *client.Client, d drivers.VolumeDriver)
 		for _, mount := range containerJSONInfo.Mounts {
 			if mount.Driver == driverName {
 				r.Incr(mount.Name)
-				log.Debugf("  name=%v (driver=%s source=%s)",
-					mount.Name, mount.Driver, mount.Source)
+				log.Debugf("  name=%v (driver=%s source=%s) (%v)",
+					mount.Name, mount.Driver, mount.Source, mount)
 			}
 		}
 	}