*: change the signature of the northbound callbacks to be more flexible

Having a fixed set of parameters for each northbound callback isn't a
good idea since it makes it difficult to add new parameters whenever
that becomes necessary, as several hundreds or thousands of existing
callbacks need to be updated accordingly.

To remediate this issue, this commit changes the signature of all
northbound callbacks to have a single parameter: a pointer to a
'nb_cb_x_args' structure (where x is different for each type
of callback). These structures encapsulate all real parameters
(both input and output) the callbacks need to have access to. And
adding a new parameter to a given callback is as simple as adding
a new field to the corresponding 'nb_cb_x_args' structure, without
needing to update any instance of that callback in any daemon.

This commit includes a .cocci semantic patch that can be used to
update old code to the new format automatically.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

1 files changed, 10 insertions, 18 deletions

diff --git a/tools/gen_northbound_callbacks.c b/tools/gen_northbound_callbacks.c
index 711898685..8dccbac3a 100644
--- a/tools/gen_northbound_callbacks.c
+++ b/tools/gen_northbound_callbacks.c
@@ -46,70 +46,62 @@ static struct nb_callback_info {
 		.operation = NB_OP_CREATE,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"enum nb_event event, const struct lyd_node *dnode, union nb_resource *resource",
+		.arguments = "struct nb_cb_create_args *args",
 	},
 	{
 		.operation = NB_OP_MODIFY,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"enum nb_event event, const struct lyd_node *dnode, union nb_resource *resource",
+		.arguments = "struct nb_cb_modify_args *args",
 	},
 	{
 		.operation = NB_OP_DESTROY,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"enum nb_event event, const struct lyd_node *dnode",
+		.arguments = "struct nb_cb_destroy_args *args",
 	},
 	{
 		.operation = NB_OP_MOVE,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"enum nb_event event, const struct lyd_node *dnode",
+		.arguments = "struct nb_cb_move_args *args",
 	},
 	{
 		.operation = NB_OP_APPLY_FINISH,
 		.optional = true,
 		.return_type = "void ",
 		.return_value = "",
-		.arguments = "const struct lyd_node *dnode",
+		.arguments = "struct nb_cb_apply_finish_args *args",
 	},
 	{
 		.operation = NB_OP_GET_ELEM,
 		.return_type = "struct yang_data *",
 		.return_value = "NULL",
-		.arguments = "const char *xpath, const void *list_entry",
+		.arguments = "struct nb_cb_get_elem_args *args",
 	},
 	{
 		.operation = NB_OP_GET_NEXT,
 		.return_type = "const void *",
 		.return_value = "NULL",
-		.arguments =
-			"const void *parent_list_entry, const void *list_entry",
+		.arguments = "struct nb_cb_get_next_args *args",
 	},
 	{
 		.operation = NB_OP_GET_KEYS,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"const void *list_entry, struct yang_list_keys *keys",
+		.arguments = "struct nb_cb_get_keys_args *args",
 	},
 	{
 		.operation = NB_OP_LOOKUP_ENTRY,
 		.return_type = "const void *",
 		.return_value = "NULL",
-		.arguments =
-			"const void *parent_list_entry, const struct yang_list_keys *keys",
+		.arguments = "struct nb_cb_lookup_entry_args *args",
 	},
 	{
 		.operation = NB_OP_RPC,
 		.return_type = "int ",
 		.return_value = "NB_OK",
-		.arguments =
-			"const char *xpath, const struct list *input, struct list *output",
+		.arguments = "struct nb_cb_rpc_args *args",
 	},
 	{
 		/* sentinel */