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, 28 insertions, 3 deletions

diff --git a/src/vlib/unix/plugin.h b/src/vlib/unix/plugin.h
index 1c74cdd241b..01fec3564fc 100644
--- a/src/vlib/unix/plugin.h
+++ b/src/vlib/unix/plugin.h
@@ -56,7 +56,14 @@
  * vlib_load_new_plugins().
  */
 
-
+/* *INDENT-OFF* */
+typedef CLIB_PACKED(struct {
+  u8 default_disabled;
+  const char version[32];
+  const char version_required[32];
+  const char *early_init;
+}) vlib_plugin_registration_t;
+/* *INDENT-ON* */
 
 typedef struct
 {
@@ -64,10 +71,22 @@ typedef struct
   u8 *filename;
   struct stat file_info;
   void *handle;
+
+  /* plugin registration */
+  vlib_plugin_registration_t *reg;
+  char *version;
 } plugin_info_t;
 
 typedef struct
 {
+  char *name;
+  u8 is_disabled;
+  u8 is_enabled;
+  u8 skip_version_check;
+} plugin_config_t;
+
+typedef struct
+{
   /* loaded plugin info */
   plugin_info_t *plugin_info;
   uword *plugin_by_name_hash;
@@ -76,8 +95,9 @@ typedef struct
   u8 *plugin_path;
   u8 *plugin_name_filter;
 
-  /* handoff structure get callback */
-  void *handoff_structure_get_cb;
+  /* plugin configs and hash by name */
+  plugin_config_t *configs;
+  uword *config_index_by_name;
 
   /* usual */
   vlib_main_t *vlib_main;
@@ -85,10 +105,15 @@ typedef struct
 
 extern plugin_main_t vlib_plugin_main;
 
+clib_error_t *vlib_plugin_config (vlib_main_t * vm, unformat_input_t * input);
 int vlib_plugin_early_init (vlib_main_t * vm);
 int vlib_load_new_plugins (plugin_main_t * pm, int from_early_init);
 void *vlib_get_plugin_symbol (char *plugin_name, char *symbol_name);
 
+#define VLIB_PLUGIN_REGISTER() \
+  vlib_plugin_registration_t vlib_plugin_registration \
+  __attribute__((__section__(".vlib_plugin_registration")))
+
 #endif /* __included_plugin_h__ */
 
 /*