tcg plugins: expose an API version concept

This is a very simple versioning API which allows the plugin
infrastructure to check the API a plugin was built against. We also
expose a min/cur API version to the plugin via the info block in case
it wants to avoid using old deprecated APIs in the future.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Robert Foley <robert.foley@linaro.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/plugins/plugin.h b/plugins/plugin.h
index 5482168d79..1aa29dcadd 100644
--- a/plugins/plugin.h
+++ b/plugins/plugin.h
@@ -14,6 +14,8 @@
 
 #include <gmodule.h>
 
+#define QEMU_PLUGIN_MIN_VERSION 0
+
 /* global state */
 struct qemu_plugin_state {
     QTAILQ_HEAD(, qemu_plugin_ctx) ctxs;