file_utils: add lxc_recvmsg_nointr_iov

src/lxc/file_utils.c

@@ -142,6 +142,24 @@ again:
 	return ret;
 }
 
+ssize_t lxc_recvmsg_nointr_iov(int sockfd, struct iovec *iov, size_t iovlen,
+			       int flags)
+{
+	ssize_t ret;
+	struct msghdr msg;
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_iov = iov;
+	msg.msg_iovlen = iovlen;
+
+again:
+	ret = recvmsg(sockfd, &msg, flags);
+	if (ret < 0 && errno == EINTR)
+		goto again;
+
+	return ret;
+}
+
 ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count, const void *expected_buf)
 {
 	ssize_t ret;

src/lxc/file_utils.h

@@ -26,6 +26,7 @@
 #include <stdio.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/uio.h>
 #include <sys/vfs.h>
 #include <unistd.h>
 
@@ -43,6 +44,8 @@ extern ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count,
 extern ssize_t lxc_read_file_expect(const char *path, void *buf, size_t count,
 				      const void *expected_buf);
 extern ssize_t lxc_recv_nointr(int sockfd, void *buf, size_t len, int flags);
+ssize_t lxc_recvmsg_nointr_iov(int sockfd, struct iovec *iov, size_t iovlen,
+			       int flags);
 
 extern bool file_exists(const char *f);
 extern int print_to_file(const char *file, const char *content);