libxl: fork: Provide LIBXL_HAVE_SIGCHLD_SELECTIVE_REAP

This is the feature test macro for libxl_childproc_sigchld_occurred
and libxl_sigchld_owner_libxl_always_selective_reap.

It is split out into this separate patch because: a single feature
test is sensible because we do not intend anyone to release or ship
libxl versions with one of these but not the other; but, the two
features are in separate patches for clarity; and, this just makes
reading the actual code easier.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Jim Fehlig <jfehlig@suse.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>

diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h
index 12d6c311a2682a9fd39c8e9ab254285aa333fd6b..1ac34c320c73b13a79e720763df6222100cdacb6 100644 (file)
--- a/tools/libxl/libxl.h
+++ b/tools/libxl/libxl.h
@@ -409,6 +409,19 @@
  */
 #define LIBXL_HAVE_DRIVER_DOMAIN_CREATION 1
 
+/*
+ * LIBXL_HAVE_SIGCHLD_SELECTIVE_REAP
+ *
+ * If this is defined:
+ *
+ * Firstly, the enum libxl_sigchld_owner (in libxl_event.h) has the
+ * value libxl_sigchld_owner_libxl_always_selective_reap which may be
+ * passed to libxl_childproc_setmode in hooks->chldmode.
+ *
+ * Secondly, the function libxl_childproc_sigchld_occurred exists.
+ */
+#define LIBXL_HAVE_SIGCHLD_OWNER_SELECTIVE_REAP 1
+
 /* Functions annotated with LIBXL_EXTERNAL_CALLERS_ONLY may not be
  * called from within libxl itself. Callers outside libxl, who
  * do not #include libxl_internal.h, are fine. */