lib: Use msghdr_extract_fds in unix_msg

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

1 files changed, 19 insertions, 56 deletions

diff --git a/source3/lib/unix_msg/unix_msg.c b/source3/lib/unix_msg/unix_msg.c
index 8d4960f6bc..c5f8143e0f 100644
--- a/source3/lib/unix_msg/unix_msg.c
+++ b/source3/lib/unix_msg/unix_msg.c
@@ -135,32 +135,6 @@ static int prepare_socket(int sock)
 	return prepare_socket_cloexec(sock);
 }
 
-static void extract_fd_array_from_msghdr(struct msghdr *msg, int **fds,
-					 size_t *num_fds)
-{
-#ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL
-	struct cmsghdr *cmsg;
-
-	for(cmsg = CMSG_FIRSTHDR(msg);
-	    cmsg != NULL;
-	    cmsg = CMSG_NXTHDR(msg, cmsg))
-	{
-		void *data = CMSG_DATA(cmsg);
-
-		if (cmsg->cmsg_type != SCM_RIGHTS) {
-			continue;
-		}
-		if (cmsg->cmsg_level != SOL_SOCKET) {
-			continue;
-		}
-
-		*fds = (int *)data;
-		*num_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof (int);
-		break;
-	}
-#endif
-}
-
 static size_t unix_dgram_msg_size(void)
 {
 	size_t msgsize = sizeof(struct unix_dgram_msg);
@@ -195,14 +169,11 @@ static void close_fd_array_dgram_msg(struct unix_dgram_msg *dmsg)
 {
 	struct msghdr_buf *hdr = unix_dgram_msghdr(dmsg);
 	struct msghdr *msg = msghdr_buf_msghdr(hdr);
-	int *fds = NULL;
-	size_t num_fds = 0;
+	size_t num_fds = msghdr_extract_fds(msg, NULL, 0);
+	int fds[num_fds];
 
-	extract_fd_array_from_msghdr(msg, &fds, &num_fds);
+	msghdr_extract_fds(msg, fds, num_fds);
 
-	/*
-	 * TODO: caveat - side-effect - changing msg ???
-	 */
 	close_fd_array(fds, num_fds);
 }
 
@@ -304,8 +275,6 @@ static void unix_dgram_recv_handler(struct poll_watch *w, int fd, short events,
 #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL
 	char buf[CMSG_SPACE(sizeof(int)*INT8_MAX)] = { 0, };
 #endif /* HAVE_STRUCT_MSGHDR_MSG_CONTROL */
-	int *fds = NULL;
-	size_t i, num_fds = 0;
 
 	iov = (struct iovec) {
 		.iov_base = (void *)ctx->recv_buf,
@@ -342,32 +311,26 @@ static void unix_dgram_recv_handler(struct poll_watch *w, int fd, short events,
 		return;
 	}
 
-	extract_fd_array_from_msghdr(&msg, &fds, &num_fds);
-
-	for (i = 0; i < num_fds; i++) {
-		int err;
+	{
+		size_t num_fds = msghdr_extract_fds(&msg, NULL, 0);
+		int fds[num_fds];
+		int i;
 
-		err = prepare_socket_cloexec(fds[i]);
-		if (err != 0) {
-			goto cleanup_fds;
-		}
-	}
+		msghdr_extract_fds(&msg, fds, num_fds);
 
-	ctx->recv_callback(ctx, ctx->recv_buf, received,
-			   fds, num_fds, ctx->private_data);
+		for (i = 0; i < num_fds; i++) {
+			int err;
 
-	/*
-	 * Close those fds that the callback has not set to -1.
-	 */
-	close_fd_array(fds, num_fds);
-
-	return;
-
-cleanup_fds:
-	close_fd_array(fds, num_fds);
+			err = prepare_socket_cloexec(fds[i]);
+			if (err != 0) {
+				close_fd_array(fds, num_fds);
+				num_fds = 0;
+			}
+		}
 
-	ctx->recv_callback(ctx, ctx->recv_buf, received,
-			   NULL, 0, ctx->private_data);
+		ctx->recv_callback(ctx, ctx->recv_buf, received,
+				   fds, num_fds, ctx->private_data);
+	}
 }
 
 static void unix_dgram_job_finished(struct poll_watch *w, int fd, short events,