+ guestfs_h *g = (guestfs_h *) data;
+ XDR xdr;
+ unsigned len;
+ int n;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "sock_read_event: %p g->state = %d, fd = %d, events = 0x%x\n",
+ g, g->state, fd, events);
+
+ if (g->sock != fd) {
+ error (g, "sock_read_event: internal error: %d != %d", g->sock, fd);
+ return;
+ }
+
+ if (g->msg_in_size <= g->msg_in_allocated) {
+ g->msg_in_allocated += 4096;
+ g->msg_in = safe_realloc (g, g->msg_in, g->msg_in_allocated);
+ }
+ n = read (g->sock, g->msg_in + g->msg_in_size,
+ g->msg_in_allocated - g->msg_in_size);
+ if (n == 0)
+ /* Disconnected? Ignore it because stdout_watch will get called
+ * and will do the cleanup.
+ */
+ return;
+
+ if (n == -1) {
+ if (errno != EAGAIN)
+ perrorf (g, "read");
+ return;
+ }
+
+ g->msg_in_size += n;
+
+ /* Have we got enough of a message to be able to process it yet? */
+ if (g->msg_in_size < 4) return;
+
+ xdrmem_create (&xdr, g->msg_in, g->msg_in_size, XDR_DECODE);
+ if (!xdr_uint32_t (&xdr, &len)) {
+ error (g, "can't decode length word");
+ goto cleanup;
+ }
+
+ /* Length is normally the length of the message, but when guestfsd
+ * starts up it sends a "magic" value (longer than any possible
+ * message). Check for this.
+ */
+ if (len == 0xf5f55ff5) {
+ if (g->state != LAUNCHING)
+ error (g, "received magic signature from guestfsd, but in state %d",
+ g->state);
+ else if (g->msg_in_size != 4)
+ error (g, "received magic signature from guestfsd, but msg size is %d",
+ g->msg_in_size);
+ else {
+ g->state = READY;
+ if (g->launch_done_cb_internal)
+ g->launch_done_cb_internal (g, g->launch_done_cb_internal_data);
+ if (g->launch_done_cb)
+ g->launch_done_cb (g, g->launch_done_cb_data);
+ }
+
+ goto cleanup;
+ }
+
+ /* If this happens, it's pretty bad and we've probably lost synchronization.*/
+ if (len > GUESTFS_MESSAGE_MAX) {
+ error (g, "message length (%u) > maximum possible size (%d)",
+ len, GUESTFS_MESSAGE_MAX);
+ goto cleanup;
+ }
+
+ if (g->msg_in_size-4 < len) return; /* Need more of this message. */
+
+ /* This should not happen, and if it does it probably means we've
+ * lost all hope of synchronization.
+ */
+ if (g->msg_in_size-4 > len) {
+ error (g, "len = %d, but msg_in_size-4 = %d", len, g->msg_in_size-4);
+ goto cleanup;
+ }
+
+ /* Not in the expected state. */
+ if (g->state != BUSY)
+ error (g, "state %d != BUSY", g->state);
+
+ /* Push the message up to the higher layer. Note that unlike
+ * launch_done_cb / launch_done_cb_internal, we only call at
+ * most one of the callback functions here.
+ */
+ g->state = READY;
+ if (g->reply_cb_internal)
+ g->reply_cb_internal (g, g->reply_cb_internal_data, &xdr);
+ else if (g->reply_cb)
+ g->reply_cb (g, g->reply_cb, &xdr);
+
+ cleanup:
+ /* Free the message buffer if it's grown excessively large. */
+ if (g->msg_in_allocated > 65536) {
+ free (g->msg_in);
+ g->msg_in = NULL;
+ g->msg_in_size = g->msg_in_allocated = 0;
+ } else
+ g->msg_in_size = 0;
+
+ xdr_destroy (&xdr);
+}
+
+/* The function is called whenever we can write something on the
+ * guestfsd (daemon inside the guest) communication socket.
+ */
+static void
+sock_write_event (void *data, int watch, int fd, int events)
+{
+ guestfs_h *g = (guestfs_h *) data;
+ int n;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "sock_write_event: %p g->state = %d, fd = %d, events = 0x%x\n",
+ g, g->state, fd, events);
+
+ if (g->sock != fd) {
+ error (g, "sock_write_event: internal error: %d != %d", g->sock, fd);
+ return;
+ }
+
+ if (g->state != BUSY) {
+ error (g, "sock_write_event: state %d != BUSY", g->state);
+ return;
+ }
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: writing %d bytes ...\n",
+ g->msg_out_size - g->msg_out_pos);
+
+ n = write (g->sock, g->msg_out + g->msg_out_pos,
+ g->msg_out_size - g->msg_out_pos);
+ if (n == -1) {
+ if (errno != EAGAIN)
+ perrorf (g, "write");
+ return;
+ }
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: wrote %d bytes\n", n);
+
+ g->msg_out_pos += n;
+
+ /* More to write? */
+ if (g->msg_out_pos < g->msg_out_size)
+ return;
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: done writing, switching back to reading events\n");
+
+ free (g->msg_out);
+ g->msg_out_pos = g->msg_out_size = 0;
+
+ if (main_loop.remove_handle (g, g->sock_watch) == -1) {
+ error (g, "remove_handle failed in sock_write_event");
+ return;
+ }
+ g->sock_watch =
+ main_loop.add_handle (g, g->sock,
+ GUESTFS_HANDLE_READABLE,
+ sock_read_event, g);
+ if (g->sock_watch == -1) {
+ error (g, "add_handle failed in sock_write_event");
+ return;
+ }
+}
+
+/* Dispatch a call to the remote daemon. This function just queues
+ * the call in msg_out, to be sent when we next enter the main loop.
+ * Returns -1 for error, or the message serial number.
+ */
+static int
+dispatch (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
+{
+ char buffer[GUESTFS_MESSAGE_MAX];
+ struct guestfs_message_header hdr;
+ XDR xdr;
+ unsigned len;
+ int serial = g->msg_next_serial++;