nbd: add notification for closing an NBDExport

In order to exit cleanly from qemu-nbd, add a callback that triggers
when an NBDExport is closed.  In the case of qemu-nbd it will exit the
main loop.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/nbd.h b/nbd.h
index 86921cd048..895820b450 100644
--- a/nbd.h
+++ b/nbd.h
@@ -79,7 +79,8 @@ typedef struct NBDExport NBDExport;
 typedef struct NBDClient NBDClient;
 
 NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,
-                          off_t size, uint32_t nbdflags);
+                          off_t size, uint32_t nbdflags,
+                          void (*close)(NBDExport *));
 void nbd_export_close(NBDExport *exp);
 void nbd_export_get(NBDExport *exp);
 void nbd_export_put(NBDExport *exp);