util: Make read_fd_link to return the length of the link read

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

protobuf.c

@@ -541,7 +541,7 @@ static char *image_name(int fd)
 {
 	static char image_path[PATH_MAX];
 
-	if (read_fd_link(fd, image_path, sizeof(image_path)) == 0)
+	if (read_fd_link(fd, image_path, sizeof(image_path)) > 0)
 		return image_path;
 	return NULL;
 }

util.c

@@ -436,14 +436,14 @@ int read_fd_link(int lfd, char *buf, size_t size)
 	}
 	buf[ret] = 0;
 
-	return 0;
+	return ret;
 }
 
 int is_anon_link_type(int lfd, char *type)
 {
 	char link[32], aux[32];
 
-	if (read_fd_link(lfd, link, sizeof(link)))
+	if (read_fd_link(lfd, link, sizeof(link)) < 0)
 		return -1;
 
 	snprintf(aux, sizeof(aux), "anon_inode:%s", type);