Plugin infrastructure improvements

This patch replaces requirement for vlib_plugin_register function
in the plugin so file and introduces new macro:

VLIB_PLUGIN_REGISTER () = {
  .version = "version string",
  .version_required = "requred version",
  .default_disabled = 1,
  .early_init = "early_init_function_name",
};

Plugin will nor be loaded if .default_disabled is set to 1
unless explicitely enabled in startup.conf.

If .verstion_required is set, plugin will not be loaded if there
is version mismatch between plugin and vpp. This can be bypassed
by setting "skip-version-check" for specific plugin.

If .early-init string is present, plugin loader will try to resolve
this specific symbol in the plugin namespace and make a function call.

Following startup.conf configuration is added:

plugins {
  path /path/to/plugin/directory
  plugin ila_plugin.so { enable skip-version-check }
  plugin acl_plugin.so { disable }
}

Change-Id: I706c691dd34d94ffe9e02b59831af8859a95f061
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 6 insertions, 9 deletions

diff --git a/src/plugins/lb/lb.c b/src/plugins/lb/lb.c
index 1d9b987095b..dc3f5be1b1b 100644
--- a/src/plugins/lb/lb.c
+++ b/src/plugins/lb/lb.c
@@ -15,6 +15,7 @@
 
 #include <lb/lb.h>
 #include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
 #include <vnet/api_errno.h>
 
 //GC runs at most once every so many seconds
@@ -730,15 +731,11 @@ int lb_vip_del(u32 vip_index)
   return 0;
 }
 
-clib_error_t *
-vlib_plugin_register (vlib_main_t * vm,
-                      vnet_plugin_handoff_t * h,
-                      int from_early_init)
-{
-  clib_error_t *error = 0;
-  return error;
-}
-
+/* *INDENT-OFF* */
+VLIB_PLUGIN_REGISTER () = {
+    .version = VPP_BUILD_VER,
+};
+/* *INDENT-ON* */
 
 u8 *format_lb_dpo (u8 * s, va_list * va)
 {