libxc: add ability to query OS interface for "fakeness"

i.e. not running on a real hypervisor

Allows users of the library to adjust behaviour. I don't especially
like this violation of the abstraction but both oxenstored and xapi
use this to avoid difficult to simulate operations when running on the
simulator.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson.citrix.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/tools/libxc/xc_private.c b/tools/libxc/xc_private.c
index aaa0d34ce3..69b674dabf 100644
--- a/tools/libxc/xc_private.c
+++ b/tools/libxc/xc_private.c
@@ -122,6 +122,19 @@ static int xc_interface_close_common(xc_interface *xch)
     return rc;
 }
 
+int xc_interface_is_fake(void)
+{
+    xc_osdep_info_t info;
+
+    if ( xc_osdep_get_info(NULL, &info) < 0 )
+        return -1;
+
+    /* Have a copy of info so can release the interface now. */
+    xc_osdep_put(&info);
+
+    return info.fake;
+}
+
 xc_interface *xc_interface_open(xentoollog_logger *logger,
                                 xentoollog_logger *dombuild_logger,
                                 unsigned open_flags)