kike: implement the WHOIS command

The code is starting to stink a bit, refactor imminent.

src/kike.c

@@ -29,6 +29,7 @@
 static struct config_item g_config_table[] =
 {
 	{ "server_name",     NULL,              "Server name"                    },
+	{ "server_info",     "My server",       "Brief server description"       },
 	{ "motd",            NULL,              "MOTD filename"                  },
 	{ "catalog",         NULL,              "catgets localization catalog"   },
 
@@ -259,6 +260,7 @@ struct client
 
 	unsigned mode;                      ///< User's mode
 	char *away_message;                 ///< Away message
+	time_t last_active;                 ///< Last PRIVMSG, to get idle time
 };
 
 static void
@@ -811,7 +813,13 @@ enum
 	IRC_RPL_ISON                  = 303,
 	IRC_RPL_UNAWAY                = 305,
 	IRC_RPL_NOWAWAY               = 306,
+	IRC_RPL_WHOISUSER             = 311,
+	IRC_RPL_WHOISSERVER           = 312,
+	IRC_RPL_WHOISOPERATOR         = 313,
 	IRC_RPL_ENDOFWHO              = 315,
+	IRC_RPL_WHOISIDLE             = 317,
+	IRC_RPL_ENDOFWHOIS            = 318,
+	IRC_RPL_WHOISCHANNELS         = 319,
 	IRC_RPL_LIST                  = 322,
 	IRC_RPL_LISTEND               = 323,
 	IRC_RPL_CHANNELMODEIS         = 324,
@@ -880,7 +888,13 @@ static const char *g_default_replies[] =
 	[IRC_RPL_ISON] = ":%s",
 	[IRC_RPL_UNAWAY] = ":You are no longer marked as being away",
 	[IRC_RPL_NOWAWAY] = ":You have been marked as being away",
+	[IRC_RPL_WHOISUSER] = "%s %s %s * :%s",
+	[IRC_RPL_WHOISSERVER] = "%s %s :%s",
+	[IRC_RPL_WHOISOPERATOR] = "%s :is an IRC operator",
 	[IRC_RPL_ENDOFWHO] = "%s :End of WHO list",
+	[IRC_RPL_WHOISIDLE] = "%s %d :seconds idle",
+	[IRC_RPL_ENDOFWHOIS] = "%s :End of WHOIS list",
+	[IRC_RPL_WHOISCHANNELS] = "%s :%s",
 	[IRC_RPL_LIST] = "%s %d :%s",
 	[IRC_RPL_LISTEND] = ":End of LIST",
 	[IRC_RPL_CHANNELMODEIS] = "%s +%s",
@@ -1347,6 +1361,8 @@ static void
 irc_handle_privmsg (const struct irc_message *msg, struct client *c)
 {
 	irc_handle_user_message (msg, c, "PRIVMSG", true);
+	// Let's not care too much about success or failure
+	c->last_active = time (NULL);
 }
 
 static void
@@ -1578,6 +1594,87 @@ irc_handle_who (const struct irc_message *msg, struct client *c)
 	irc_send_reply (c, IRC_RPL_ENDOFWHO, shown_mask);
 }
 
+static void
+irc_send_whois_reply (struct client *c, const struct client *target)
+{
+	const char *nick = target->nickname;
+	irc_send_reply (c, IRC_RPL_WHOISUSER, nick, target->username,
+		target->hostname, target->realname);
+	irc_send_reply (c, IRC_RPL_WHOISSERVER, nick, target->ctx->server_name,
+		str_map_find (&c->ctx->config, "server_info"));
+	if (target->mode & IRC_USER_MODE_OPERATOR)
+		irc_send_reply (c, IRC_RPL_WHOISOPERATOR, nick);
+	irc_send_reply (c, IRC_RPL_WHOISIDLE, nick,
+		(int) (time (NULL) - target->last_active));
+
+	struct str_map_iter iter;
+	str_map_iter_init (&iter, &c->ctx->channels);
+	struct channel *chan;
+	struct channel_user *channel_user;
+	while ((chan = str_map_iter_next (&iter)))
+		if ((channel_user = channel_get_user (chan, target))
+		 && (!(chan->modes & (IRC_CHAN_MODE_PRIVATE | IRC_CHAN_MODE_SECRET))
+			|| channel_get_user (chan, c)))
+		{
+			struct str item;
+			str_init (&item);
+			if (channel_user->modes & IRC_CHAN_MODE_OPERATOR)
+				str_append_c (&item, '@');
+			else if (channel_user->modes & IRC_CHAN_MODE_VOICE)
+				str_append_c (&item, '+');
+			str_append (&item, chan->name);
+			str_append_c (&item, ' ');
+
+			// TODO: try to merge the results into as few messages as possible
+			irc_send_reply (c, IRC_RPL_WHOISCHANNELS, nick, item.str);
+
+			str_free (&item);
+		}
+
+	irc_send_reply (c, IRC_RPL_ENDOFWHOIS, nick);
+}
+
+static void
+irc_handle_whois (const struct irc_message *msg, struct client *c)
+{
+	if (msg->params.len < 1)
+		RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
+	if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[0]))
+		RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[0]);
+
+	struct str_vector masks;
+	str_vector_init (&masks);
+	const char *masks_str = msg->params.vector[msg->params.len > 1];
+	split_str_ignore_empty (masks_str, ',', &masks);
+	for (size_t i = 0; i < masks.len; i++)
+	{
+		const char *mask = masks.vector[i];
+		struct client *target;
+		if (!strpbrk (mask, "*?"))
+		{
+			if (!(target = str_map_find (&c->ctx->users, mask)))
+				irc_send_reply (c, IRC_ERR_NOSUCHNICK, mask);
+			else
+				irc_send_whois_reply (c, target);
+		}
+		else
+		{
+			struct str_map_iter iter;
+			str_map_iter_init (&iter, &c->ctx->users);
+			bool found = false;
+			while ((target = str_map_iter_next (&iter))
+				&& !irc_fnmatch (mask, target->nickname))
+			{
+				irc_send_whois_reply (c, target);
+				found = true;
+			}
+			if (!found)
+				irc_send_reply (c, IRC_ERR_NOSUCHNICK, mask);
+		}
+	}
+	str_vector_free (&masks);
+}
+
 static void
 irc_send_rpl_topic (struct client *c, struct channel *chan)
 {
@@ -1901,6 +1998,7 @@ irc_register_handlers (struct server_context *ctx)
 		{ "LIST",     true,  irc_handle_list     },
 		{ "NAMES",    true,  irc_handle_names    },
 		{ "WHO",      true,  irc_handle_who      },
+		{ "WHOIS",    true,  irc_handle_whois    },
 		{ "ISON",     true,  irc_handle_ison     },
 	};
 
@@ -2239,6 +2337,7 @@ on_irc_client_available (const struct pollfd *pfd, void *user_data)
 		c->ctx = ctx;
 		c->socket_fd = fd;
 		c->hostname = xstrdup (host);
+		c->last_active = time (NULL);
 		LIST_PREPEND (ctx->clients, c);
 		ctx->n_clients++;