kike: refactor CAP processing

1 files changed, 138 insertions, 73 deletions

diff --git a/kike.c b/kike.c
index 948e635..83aa659 100644
--- a/kike.c
+++ b/kike.c
@@ -319,7 +319,7 @@ struct client
 	bool half_closed;                   ///< Closing link: conn. is half-closed
 
 	unsigned long cap_version;          ///< CAP protocol version
-	unsigned caps;                      ///< Enabled capabilities
+	unsigned caps_enabled;              ///< Enabled capabilities
 
 	bool ssl_rx_want_tx;                ///< SSL_read() wants to write
 	bool ssl_tx_want_rx;                ///< SSL_write() wants to read
@@ -545,6 +545,7 @@ struct server_context
 	struct str_map users;               ///< Maps nicknames to clients
 	struct str_map channels;            ///< Maps channel names to data
 	struct str_map handlers;            ///< Message handlers
+	struct str_map cap_handlers;        ///< CAP message handlers
 
 	struct poller poller;               ///< Manages polled description
 	struct poller_timer quit_timer;     ///< Quit timeout timer
@@ -582,6 +583,8 @@ server_context_init (struct server_context *self)
 	self->channels.free = (void (*) (void *)) channel_delete;
 	str_map_init (&self->handlers);
 	self->handlers.key_xfrm = irc_strxfrm;
+	str_map_init (&self->cap_handlers);
+	self->cap_handlers.key_xfrm = irc_strxfrm;
 
 	poller_init (&self->poller);
 	poller_timer_init (&self->quit_timer, &self->poller);
@@ -631,6 +634,7 @@ server_context_free (struct server_context *self)
 	str_map_free (&self->users);
 	str_map_free (&self->channels);
 	str_map_free (&self->handlers);
+	str_map_free (&self->cap_handlers);
 	poller_free (&self->poller);
 
 	str_vector_free (&self->motd);
@@ -1121,97 +1125,157 @@ irc_try_finish_registration (struct client *c)
 			ctx->server_name, c->nickname, c->ssl_cert_fingerprint);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+struct irc_cap_args
+{
+	const char *subcommand;             ///< The subcommand being processed
+	const char *full_params;            ///< Whole parameter string
+	struct str_vector params;           ///< Split parameters
+	const char *target;                 ///< Target parameter for replies
+};
+
 static void
-irc_handle_cap (const struct irc_message *msg, struct client *c)
+irc_handle_cap_ls (struct client *c, struct irc_cap_args *a)
 {
-	if (msg->params.len < 1)
-		RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
+	if (a->params.len == 1
+	 && !xstrtoul (&c->cap_version, a->params.vector[0], 10))
+		irc_send_reply (c, IRC_ERR_INVALIDCAPCMD,
+			a->subcommand, "Ignoring invalid protocol version number");
 
-	struct str_vector v;
-	str_vector_init (&v);
+	c->cap_negotiating = true;
+	client_send (c, "CAP %s LS :multi-prefix", a->target);
+}
 
-	const char *subcommand = msg->params.vector[0];
-	const char *params = "";
-	if (msg->params.len > 1)
-	{
-		params = msg->params.vector[1];
-		split_str_ignore_empty (params, ' ', &v);
-	}
+static void
+irc_handle_cap_list (struct client *c, struct irc_cap_args *a)
+{
+	struct str_vector caps;
+	str_vector_init (&caps);
 
-	const char *target = c->nickname ? c->nickname : "*";
-	if (!irc_strcmp (subcommand, "LS"))
-	{
-		if (v.len == 1 && !xstrtoul (&c->cap_version, v.vector[0], 10))
-			irc_send_reply (c, IRC_ERR_INVALIDCAPCMD,
-				subcommand, "Ignoring invalid protocol version number");
+	if (c->caps_enabled & IRC_CAP_MULTI_PREFIX)
+		str_vector_add (&caps, "multi-prefix");
 
-		c->cap_negotiating = true;
-		client_send (c, "CAP %s LS :multi-prefix", target);
-	}
-	else if (!irc_strcmp (subcommand, "LIST"))
-	{
-		struct str_vector caps;
-		str_vector_init (&caps);
+	char *caps_str = join_str_vector (&caps, ' ');
+	str_vector_free (&caps);
+	client_send (c, "CAP %s LIST :%s", a->target, caps_str);
+	free (caps_str);
+}
 
-		if (c->caps & IRC_CAP_MULTI_PREFIX)
-			str_vector_add (&caps, "multi-prefix");
+static unsigned
+irc_decode_capability (const char *name)
+{
+	if (!strcmp (name, "multi-prefix"))
+		return IRC_CAP_MULTI_PREFIX;
+	return 0;
+}
 
-		char *caps_str = join_str_vector (&caps, ' ');
-		str_vector_free (&caps);
-		client_send (c, "CAP %s LIST :%s", target, caps_str);
-		free (caps_str);
-	}
-	else if (!irc_strcmp (subcommand, "REQ"))
-	{
-		c->cap_negotiating = true;
+static void
+irc_handle_cap_req (struct client *c, struct irc_cap_args *a)
+{
+	c->cap_negotiating = true;
 
-		unsigned new_caps = c->caps;
-		bool success = true;
-		for (size_t i = 0; i < v.len; i++)
+	unsigned new_caps = c->caps_enabled;
+	bool success = true;
+	for (size_t i = 0; i < a->params.len; i++)
+	{
+		bool removing = false;
+		const char *name = a->params.vector[i];
+		if (*name == '-')
 		{
-			bool neg = false;
-			const char *name = v.vector[i];
-			if (*name == '-')
-			{
-				neg = true;
-				name++;
-			}
-			unsigned cap = 0;
-			if (!strcmp (name, "multi-prefix"))
-				cap = IRC_CAP_MULTI_PREFIX;
-			else
-				success = false;
-
-			if (neg)
-				new_caps &= ~cap;
-			else
-				new_caps |=  cap;
+			removing = true;
+			name++;
 		}
 
-		if (success)
-		{
-			c->caps = new_caps;
-			client_send (c, "CAP %s NAK :%s", target, params);
-		}
+		unsigned cap;
+		if (!(cap = irc_decode_capability (name)))
+			success = false;
+		else if (removing)
+			new_caps &= ~cap;
 		else
-			client_send (c, "CAP %s ACK :%s", target, params);
+			new_caps |=  cap;
 	}
-	else if (!irc_strcmp (subcommand, "ACK"))
+
+	if (success)
+	{
+		c->caps_enabled = new_caps;
+		client_send (c, "CAP %s ACK :%s", a->target, a->full_params);
+	}
+	else
+		client_send (c, "CAP %s NAK :%s", a->target, a->full_params);
+}
+
+static void
+irc_handle_cap_ack (struct client *c, struct irc_cap_args *a)
+{
+	if (a->params.len)
+		irc_send_reply (c, IRC_ERR_INVALIDCAPCMD,
+			a->subcommand, "No acknowledgable capabilities supported");
+}
+
+static void
+irc_handle_cap_end (struct client *c, struct irc_cap_args *a)
+{
+	(void) a;
+
+	c->cap_negotiating = false;
+	irc_try_finish_registration (c);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+struct irc_cap_command
+{
+	const char *name;
+	void (*handler) (struct client *, struct irc_cap_args *);
+};
+
+static void
+irc_register_cap_handlers (struct server_context *ctx)
+{
+	static const struct irc_cap_command cap_handlers[] =
 	{
-		if (v.len)
-			irc_send_reply (c, IRC_ERR_INVALIDCAPCMD,
-				subcommand, "No acknowledgable capabilities supported");
+		{ "LS",   irc_handle_cap_ls   },
+		{ "LIST", irc_handle_cap_list },
+		{ "REQ",  irc_handle_cap_req  },
+		{ "ACK",  irc_handle_cap_ack  },
+		{ "END",  irc_handle_cap_end  },
+	};
+
+	for (size_t i = 0; i < N_ELEMENTS (cap_handlers); i++)
+	{
+		const struct irc_cap_command *cmd = &cap_handlers[i];
+		str_map_set (&ctx->cap_handlers, cmd->name, (void *) cmd);
 	}
-	else if (!irc_strcmp (subcommand, "END"))
+}
+
+static void
+irc_handle_cap (const struct irc_message *msg, struct client *c)
+{
+	if (msg->params.len < 1)
+		RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
+
+	struct irc_cap_args args;
+	args.target = c->nickname ? c->nickname : "*";
+	args.subcommand = msg->params.vector[0];
+	args.full_params = "";
+	str_vector_init (&args.params);
+
+	if (msg->params.len > 1)
 	{
-		c->cap_negotiating = false;
-		irc_try_finish_registration (c);
+		args.full_params = msg->params.vector[1];
+		split_str_ignore_empty (args.full_params, ' ', &args.params);
 	}
-	else
+
+	struct irc_cap_command *cmd =
+		str_map_find (&c->ctx->cap_handlers, args.subcommand);
+	if (!cmd)
 		irc_send_reply (c, IRC_ERR_INVALIDCAPCMD,
-			subcommand, "Invalid CAP subcommand");
+			args.subcommand, "Invalid CAP subcommand");
+	else
+		cmd->handler (c, &args);
 
-	str_vector_free (&v);
+	str_vector_free (&args.params);
 }
 
 static void
@@ -1994,7 +2058,7 @@ irc_append_prefixes (struct client *c, struct channel_user *user,
 
 	if (prefixes.len)
 	{
-		if (c->caps & IRC_CAP_MULTI_PREFIX)
+		if (c->caps_enabled & IRC_CAP_MULTI_PREFIX)
 			str_append   (output, prefixes.str);
 		else
 			str_append_c (output, prefixes.str[0]);
@@ -3508,6 +3572,7 @@ main (int argc, char *argv[])
 	struct server_context ctx;
 	server_context_init (&ctx);
 	irc_register_handlers (&ctx);
+	irc_register_cap_handlers (&ctx);
 
 	struct error *e = NULL;
 	if (!read_config_file (&ctx.config, &e))