From 71427e54fa17dacd1ace6077bffb9f9b9d456ebb Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Wed, 13 Apr 2011 21:16:14 +0200
Subject: [PATCH] add some infrastructure code for proto handlers

---
 config.c       |  2 +-
 config/network |  3 +++
 interface.c    | 11 +++-------
 interface.h    |  4 +++-
 proto.c        | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 proto.h        | 10 ++++++++-
 6 files changed, 83 insertions(+), 14 deletions(-)

diff --git a/config.c b/config.c
index 2442eff..94a7fdb 100644
--- a/config.c
+++ b/config.c
@@ -34,7 +34,7 @@ config_parse_interface(struct uci_section *s)
 
 	DPRINTF("Create interface '%s'\n", s->e.name);
 
-	iface = alloc_interface(s->e.name);
+	iface = alloc_interface(s->e.name, s);
 	if (!iface)
 		return;
 
diff --git a/config/network b/config/network
index 0a02e89..1f803a0 100644
--- a/config/network
+++ b/config/network
@@ -21,6 +21,9 @@ config interface lan
 	option ipaddr	192.168.1.1
 	option netmask	255.255.255.0
 
+config interface dummy
+	option ifname	eth0.4
+	option proto	none
 
 config interface lan2
 	option ifname	eth0.3
diff --git a/interface.c b/interface.c
index 06a36ed..ef176f6 100644
--- a/interface.c
+++ b/interface.c
@@ -175,7 +175,7 @@ void interface_set_proto_state(struct interface *iface, struct interface_proto_s
 }
 
 struct interface *
-alloc_interface(const char *name)
+alloc_interface(const char *name, struct uci_section *s)
 {
 	struct interface *iface;
 
@@ -184,19 +184,14 @@ alloc_interface(const char *name)
 		return iface;
 
 	iface = calloc(1, sizeof(*iface));
-
-	interface_set_proto_state(iface, get_default_proto());
-	if (!iface->proto) {
-		free(iface);
-		return NULL;
-	}
-
 	iface->main_dev.cb = interface_cb;
 	iface->l3_iface = &iface->main_dev;
 	strncpy(iface->name, name, sizeof(iface->name) - 1);
 	list_add(&iface->list, &interfaces);
 	INIT_LIST_HEAD(&iface->errors);
 
+	proto_attach_interface(iface, s);
+
 	netifd_ubus_add_interface(iface);
 
 	return iface;
diff --git a/interface.h b/interface.h
index 92bae5a..e3b5ff7 100644
--- a/interface.h
+++ b/interface.h
@@ -55,9 +55,11 @@ struct interface {
 };
 
 struct interface *get_interface(const char *name);
-struct interface *alloc_interface(const char *name);
+struct interface *alloc_interface(const char *name, struct uci_section *s);
 void free_interface(struct interface *iface);
 
+void interface_set_proto_state(struct interface *iface, struct interface_proto_state *state);
+
 int set_interface_up(struct interface *iface);
 int set_interface_down(struct interface *iface);
 
diff --git a/proto.c b/proto.c
index b16600c..ea6e138 100644
--- a/proto.c
+++ b/proto.c
@@ -6,6 +6,20 @@
 #include "interface.h"
 #include "proto.h"
 
+static struct avl_tree handlers;
+
+void add_proto_handler(struct proto_handler *p)
+{
+	if (!handlers.comp)
+		avl_init(&handlers, avl_strcmp, false, NULL);
+
+	if (p->avl.key)
+		return;
+
+	p->avl.key = p->name;
+	avl_insert(&handlers, &p->avl);
+}
+
 static void
 default_proto_free(struct interface_proto_state *proto)
 {
@@ -13,24 +27,71 @@ default_proto_free(struct interface_proto_state *proto)
 }
 
 static int
-default_proto_handler(struct interface_proto_state *proto,
+invalid_proto_handler(struct interface_proto_state *proto,
+		      enum interface_proto_cmd cmd, bool force)
+{
+	return -1;
+}
+
+static int
+no_proto_handler(struct interface_proto_state *proto,
 		      enum interface_proto_cmd cmd, bool force)
 {
 	return 0;
 }
 
-struct interface_proto_state *get_default_proto(void)
+static struct interface_proto_state *get_default_proto(void)
 {
 	struct interface_proto_state *proto;
 
 	proto = calloc(1, sizeof(*proto));
-	proto->handler = default_proto_handler;
 	proto->free = default_proto_free;
 	proto->flags = PROTO_FLAG_IMMEDIATE;
 
 	return proto;
 }
 
+void proto_attach_interface(struct interface *iface, struct uci_section *s)
+{
+	struct interface_proto_state *state = NULL;
+	struct proto_handler *proto = NULL;
+	const char *proto_name;
+	const char *error = NULL;
+
+	proto_name = uci_lookup_option_string(uci_ctx, s, "proto");
+	if (!proto_name) {
+		error = "NO_PROTO";
+		goto error;
+	}
+
+	if (!strcmp(proto_name, "none")) {
+		state = get_default_proto();
+		state->handler = no_proto_handler;
+		goto out;
+	}
+
+	if (handlers.comp)
+		proto = avl_find_element(&handlers, proto_name, proto, avl);
+
+	if (!proto) {
+		error = "INVALID_PROTO";
+		goto error;
+	}
+
+	state = proto->attach(proto, iface);
+
+error:
+	if (error) {
+		interface_add_error(iface, "proto", error, NULL, 0);
+		state = get_default_proto();
+		state->handler = invalid_proto_handler;
+	}
+
+out:
+	interface_set_proto_state(iface, state);
+}
+
+
 int interface_proto_event(struct interface_proto_state *proto,
 			  enum interface_proto_cmd cmd, bool force)
 {
diff --git a/proto.h b/proto.h
index d94b992..776cc36 100644
--- a/proto.h
+++ b/proto.h
@@ -29,7 +29,15 @@ struct interface_proto_state {
 	void (*free)(struct interface_proto_state *);
 };
 
-struct interface_proto_state *get_default_proto(void);
+struct proto_handler {
+	struct avl_node avl;
+
+	const char *name;
+	struct interface_proto_state * (*attach)(struct proto_handler *h, struct interface *);
+};
+
+void add_proto_handler(struct proto_handler *p);
+void proto_attach_interface(struct interface *iface, struct uci_section *s);
 int interface_proto_event(struct interface_proto_state *proto,
 			  enum interface_proto_cmd cmd, bool force);
 
-- 
2.11.0