send.c re-work PREFIXES ======== Server prefixes are the ":%s" strings at the beginning of messages. They are used by servers to route the message properly and by servers to local clients to update their idea of who is whom. ":nick!user@host" is a prefix ":name" where name is either a nick or name of a server is another valid prefix. Typical prefix for a local client to a channel: ":Dianora!db@irc.db.net" for a prefix to a remote server: ":Dianora" e.g. as seen locally on a channel: ":Dianora!db@irc.db.net PRIVMSG #us-opers :ON TOP OF ...\r\n" e.g. as seen sent to a remote server: ":Dianora PRIVMSG #us-opers :ON TOP OF ...\r\n" It has been argued that full prefixes sent locally are a waste of bandwidth (Isomer from Undernet has argued this). i.e. instead of sending: ":nick!user@host" for a local prefix, one could just send ":nick".. Unfortunately, this breaks many clients badly. Personally I feel that until clients are updated to understand that a full prefix isn't always going to be sent, that this should be held off on. As much as possible, prefix generation is now moved "upstairs" as much as possible. i.e. if its known its a local client only, then the onus of the prefix generation, is the users, not hidden in send.c This allows somewhat faster code to be written, as the prefix doesn't have to be regenerated over and over again. Prefixes aren't sent in all cases, such as a new user using NICK A prefix is needed when it must be routed. i.e. NICK newnick There is obviously no prefix needed from a locally connected client. FUNCTIONS ========= sendto_one() - Should be used for _local_ clients only it expects the prefix to be pre-built by user. usage - sendto_one(struct Client *to, char *pattern, ...); typical use: sendto_one(acptr,":%s NOTICE %s :I'm tired", me.name); Note: This was from a server "me" hence only one name in prefix. This would be an example of a client sptr, noticing acptr IF acptr is known to be a local client: sendto_one(acptr,":%s!%s@%s NOTICE %s :You there?", sptr->name, sptr->username, sptr->host, acptr->name); sendto_channel_butone() - This function sends a var args message to a channel globally, except to the client specified as "one", the prefix is built by this function on the fly as it has to be sent both to local clients on this server and to remote servers. usage - sendto_channel_butone(struct Client *one, struct Client *from, struct Channel *chptr, const char *pattern, ... ); sendto_channel_butone(cptr, sptr, chptr "PRIVMSG %s :HI!", chptr->chname); e.g. if channel message is coming from "cptr" it must not be sent back to cptr. sendto_ll_serv_butone(struct Client *one, struct Client *sptr, int add, const char *pattern, ...) - This function is almost identical to sendto_channel_butone however, it will also not send on a nick as given by sptr, if target server does not "know" about it. As the name implies, it is used for "lazylinks" sendto_serv_butone() - This function sends specified var args message to all connected servers except the client "one" usage - sendto_serv_butone(struct Client *one, const char *pattern, ... ); sendto_cap_serv_butone() - This function sends specified var args message to all connected servers except the client "one" with capability specified. NOTE: sendto_serv_butone() could be replaced with a generalized version of this function. i.e. CAP_ALL usage - sendto_cap_serv_butone(int cap, struct Client *one, const char *pattern, ... ); sendto_common_channels_local() - This function is used only by m_nick and exit_one_client its used to propagate nick changes to all channels user is in, and QUIT messages to all channels user is in. As it only sends to local clients, prefix generation is left to the user. It also sends the message to the user if the user isn't on any channels. usage - sendto_common_channels_local(struct Client *user, const char *pattern, ...); sendto_channel_local() - This function is used only to send locally, never to remote servers. This is useful when removing local chanops, or adding a local chanop. MODE/SJOIN sent to remote server allows that server to propagate mode changes to its clients locally. usage - sendto_channel_local(type, struct Channel *chptr, const char *pattern, ... ); prefix must be pre-built. type is a flag denoting ONE of ALL_MEMBERS - all members locally are sent to NON_CHANOPS - only non-chanops see this ONLY_CHANOPS_VOICED - both chanops and voiced see this ONLY_CHANOPS - only chanops see this sendto_match_butone() match_it() - both only used for the old style oper masking i.e. /msg #hostmask which in hyb7 is /msg $#hostmask or /msg $servermask in hyb7 /msg $$servermask usage - match_it(struct Client *one, const char *mask, int what); one is the client to match on either hostmask or servermask mask is the actual mask what is either MATCH_HOST or MATCH_SERVER usage - sendto_match_butone(struct Client *one, struct Client *from, char *mark, int what, const char *pattern, ... ); sendto_channel_remote() - Is only used to send a message to a remote server sendto_match_cap_servs() - Is used only to send MODE lists to remote server who are capable of it. i.e. MODE #channel +e nick!user@host sendto_match_noncap_servs() - Is used only to send MODE lists to remote servers that are not capable of it. i.e. MODE #channel +o nick - This allows you to send a MODE #channel +h nick via sendto_match_cap_servs and MODE #channel +o nick to servers which dont support it. sendto_anywhere() - Allows the sending of a message to any client on the net without knowing whether its local or remote. The penalty is the calculation of a run-time prefix. It is less efficient then sendto_one() usage - sendto_anywhere(struct Client *to, struct Client *from, const char *pattern, ...); e.g. sendto_anywhere(acptr, sptr, "PRIVMSG Larz :Hi, Where ever you are"); sendto_realops_flags() - combines old sendto_realops and sendto_realops_flags sends specified message to opers locally only depending on flags. FLAGS_ALL is a special case to send to any oper. usage - sendto_realops_flags(int flags, const char *pattern, ... ); e.g. sendto_realops_flags(FLAGS_ALL, "Don't eat the yellow snow"); sendto_wallops_flags() - sends specified message to opers locally, depending on flags. used for messages that need to be in wallops form usage - sendto_wall_flags(int flags, struct Client *, const char *patterm ...); e.g. sendto_wallops_flags(FLAGS_LOCOPS, sptr, "Message"); ts_warn() - Only used to send warning messages to all opers without flooding them with warnings. It limits the number of warnings to no more than 5 every 5 seconds. It probably can go away now. usage - ts_warn(const char *pattern, ... ); *** LOCAL HELPER FUNCTIONS (static) *** sendto_format() - Used to format a varargs buffer into given buffer returns length of buffer built, enforces RFC1459 length limits and appends \r\n as per rfc. usage - sendto_format(char *sendbuf, const char *pattern, ... ); send_trim() - This local function simply trims a char string to fit inside 512 bytes as per rfc1459, adding a cr/lf pair as needed. It does not check to make sure original string has a cr/lf. usage - int send_trim(char buffer, int len); returns length as modified or not, modifies buffer in-place. sendto_list_local() - This local function sends given message to given dlink_list with data == a local client. This is used by sendto_common_channels_local() and by sendto_channel_local() It could easily be extended to sendto "groups" of otherwise unrelated users, not just channel groups. usage - sendto_list_local(dlink_list *list, const char *sendbuf, int len); sendto_list_anywhere() - This local function sends a message to all members as given in a dlink_list, whether they are remote or local clients. It is used by sendto_channel_butone() It could easily be extended to sendto "groups" of otherwise unrelated users, not just channel groups. usage: sendto_list_anywhere(struct Client *one, struct Client *from, dlink_list *list, const char *local_sendbuf, int local_len, const char *remote_sendbuf, int remote_len); send_message() - This local function does the actual send of message usage: send_message(struct Client *to, char *msg, int len); The message has to be pre-formatted and the length must be pre-calculated. -- Diane Bruce $Id: send.txt,v 1.2 2004/02/02 23:43:38 ircd Exp $