From ecad9f32c82f50312010ab41f7702d1329bc511e Mon Sep 17 00:00:00 2001
From: Alexander Barton <alex@barton.de>
Date: Sat, 16 Jan 2010 22:30:55 +0100
Subject: [PATCH] Clean up and document IRC_JOIN() and join_allowed() functions

---
 src/ngircd/irc-channel.c | 72 ++++++++++++++++++++++++++--------------
 1 file changed, 47 insertions(+), 25 deletions(-)

diff --git a/src/ngircd/irc-channel.c b/src/ngircd/irc-channel.c
index af0f0668..010be352 100644
--- a/src/ngircd/irc-channel.c
+++ b/src/ngircd/irc-channel.c
@@ -62,9 +62,18 @@ part_from_all_channels(CLIENT* client, CLIENT *target)
 }
 
 
+/**
+ * Check weather a local client is allowed to join an already existing
+ * channel or not.
+ * @param Client Client that sent the JOIN command
+ * @param chan Channel to check
+ * @param channame Name of the channel
+ * @param key Provided channel key (or NULL if none has been provided)
+ * @return true if client is allowed to join channel, false otherwise
+ */
 static bool
-join_allowed(CLIENT *Client, CLIENT *target, CHANNEL *chan,
-			const char *channame, const char *key)
+join_allowed(CLIENT *Client, CHANNEL *chan, const char *channame,
+	     const char *key)
 {
 	bool is_invited, is_banned;
 	const char *channel_modes;
@@ -73,32 +82,40 @@ join_allowed(CLIENT *Client, CLIENT *target, CHANNEL *chan,
 	if (strchr(Client_Modes(Client), 'o'))
 		return true;
 
-	is_banned = Lists_Check(Channel_GetListBans(chan), target);
-	is_invited = Lists_Check(Channel_GetListInvites(chan), target);
+	is_banned = Lists_Check(Channel_GetListBans(chan), Client);
+	is_invited = Lists_Check(Channel_GetListInvites(chan), Client);
 
 	if (is_banned && !is_invited) {
-		IRC_WriteStrClient(Client, ERR_BANNEDFROMCHAN_MSG, Client_ID(Client), channame);
+		/* Client is banned from channel (and not on invite list) */
+		IRC_WriteStrClient(Client, ERR_BANNEDFROMCHAN_MSG,
+				   Client_ID(Client), channame);
 		return false;
 	}
 
 	channel_modes = Channel_Modes(chan);
 	if ((strchr(channel_modes, 'i')) && !is_invited) {
-		/* Channel is "invite-only" (and Client wasn't invited) */
-		IRC_WriteStrClient(Client, ERR_INVITEONLYCHAN_MSG, Client_ID(Client), channame);
+		/* Channel is "invite-only" and client is not on invite list */
+		IRC_WriteStrClient(Client, ERR_INVITEONLYCHAN_MSG,
+				   Client_ID(Client), channame);
 		return false;
 	}
 
-	/* Is the channel protected by a key? */
-	if (!Channel_CheckKey(chan, target, key ? key : "")) {
+	if (!Channel_CheckKey(chan, Client, key ? key : "")) {
+		/* Channel is protected by a channel key and the client
+		 * didn't specify the correct one */
 		IRC_WriteStrClient(Client, ERR_BADCHANNELKEY_MSG,
 				   Client_ID(Client), channame);
 		return false;
 	}
-	/* Are there already too many members? */
-	if ((strchr(channel_modes, 'l')) && (Channel_MaxUsers(chan) <= Channel_MemberCount(chan))) {
-		IRC_WriteStrClient(Client, ERR_CHANNELISFULL_MSG, Client_ID(Client), channame);
+
+	if ((strchr(channel_modes, 'l')) &&
+	    (Channel_MaxUsers(chan) <= Channel_MemberCount(chan))) {
+		/* There are more clints joined to this channel than allowed */
+		IRC_WriteStrClient(Client, ERR_CHANNELISFULL_MSG,
+				   Client_ID(Client), channame);
 		return false;
 	}
+
 	return true;
 }
 
@@ -270,20 +287,23 @@ IRC_JOIN( CLIENT *Client, REQUEST *Req )
 
 		/* Local client? */
 		if (Client_Type(Client) == CLIENT_USER) {
-			/* Test if the user has reached his maximum channel count */
-			if ((Conf_MaxJoins > 0) && (Channel_CountForUser(Client) >= Conf_MaxJoins))
-				return IRC_WriteStrClient(Client, ERR_TOOMANYCHANNELS_MSG,
-							Client_ID(Client), channame);
-			if (!chan) {
-				/*
-				 * New Channel: first user will be channel operator
-				 * unless this is a modeless channel.
-				 */
+			/* Test if the user has reached the channel limit */
+			if ((Conf_MaxJoins > 0) &&
+			    (Channel_CountForUser(Client) >= Conf_MaxJoins))
+				return IRC_WriteStrClient(Client,
+						ERR_TOOMANYCHANNELS_MSG,
+						Client_ID(Client), channame);
+			if (chan) {
+				/* Already existing channel: check if the
+				 * client is allowed to join */
+				if (!join_allowed(Client, chan, channame, key))
+					break;
+			} else {
+				/* New channel: first user will become channel
+				 * operator unless this is a modeless channel */
 				if (*channame != '+')
 					flags = "o";
-			} else
-				if (!join_allowed(Client, target, chan, channame, key))
-					break;
+			}
 
 			/* Local client: update idle time */
 			Conn_UpdateIdle(Client_Conn(Client));
@@ -293,7 +313,9 @@ IRC_JOIN( CLIENT *Client, REQUEST *Req )
 			 * that the "one shot" entries (generated by INVITE
 			 * commands) in this list become deleted when a user
 			 * joins a channel this way. */
-			if (chan) (void)Lists_Check(Channel_GetListInvites(chan), target);
+			if (chan)
+				(void)Lists_Check(Channel_GetListInvites(chan),
+						  target);
 		}
 
 		/* Join channel (and create channel if it doesn't exist) */
-- 
2.39.2