source: irc.c @ e731120

  /********************************************************************\
  * BitlBee -- An IRC to other IM-networks gateway                     *
  *                                                                    *
  * Copyright 2002-2004 Wilmer van der Gaast and others                *
  \********************************************************************/

/* The big hairy IRCd part of the project                               */

/*
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License with
  the Debian GNU/Linux distribution in /usr/share/common-licenses/GPL;
  if not, write to the Free Software Foundation, Inc., 59 Temple Place,
  Suite 330, Boston, MA  02111-1307  USA
*/

#define BITLBEE_CORE
#include "bitlbee.h"
#include "crypting.h"
#include "ipc.h"

static gboolean irc_userping( gpointer _irc, int fd, b_input_condition cond );

GSList *irc_connection_list = NULL;

static char *passchange( set_t *set, char *value )
{
        irc_t *irc = set->data;
        
        irc_setpass( irc, value );
        irc_usermsg( irc, "Password successfully changed" );
        return NULL;
}

irc_t *irc_new( int fd )
{
        irc_t *irc;
        struct sockaddr_storage sock;
        socklen_t socklen = sizeof( sock );
        
        irc = g_new0( irc_t, 1 );
        
        irc->fd = fd;
        sock_make_nonblocking( irc->fd );
        
        irc->r_watch_source_id = b_input_add( irc->fd, GAIM_INPUT_READ, bitlbee_io_current_client_read, irc );
        
        irc->status = USTATUS_OFFLINE;
        irc->last_pong = gettime();
        
        irc->userhash = g_hash_table_new( g_str_hash, g_str_equal );
        irc->watches = g_hash_table_new( g_str_hash, g_str_equal );
        
        strcpy( irc->umode, UMODE );
        irc->mynick = g_strdup( ROOT_NICK );
        irc->channel = g_strdup( ROOT_CHAN );
        
        if( global.conf->hostname )
        {
                irc->myhost = g_strdup( global.conf->hostname );
        }
        else if( getsockname( irc->fd, (struct sockaddr*) &sock, &socklen ) == 0 ) 
        {
                char buf[NI_MAXHOST+1];

                if( getnameinfo( (struct sockaddr *) &sock, socklen, buf,
                                 NI_MAXHOST, NULL, -1, 0 ) == 0 )
                {
                        irc->myhost = g_strdup( ipv6_unwrap( buf ) );
                }
        }
        
        if( getpeername( irc->fd, (struct sockaddr*) &sock, &socklen ) == 0 )
        {
                char buf[NI_MAXHOST+1];

                if( getnameinfo( (struct sockaddr *)&sock, socklen, buf,
                                 NI_MAXHOST, NULL, -1, 0 ) == 0 )
                {
                        irc->host = g_strdup( ipv6_unwrap( buf ) );
                }
        }
        
        if( irc->host == NULL )
                irc->host = g_strdup( "localhost.localdomain" );
        if( irc->myhost == NULL )
                irc->myhost = g_strdup( "localhost.localdomain" );
        
        if( global.conf->ping_interval > 0 && global.conf->ping_timeout > 0 )
                irc->ping_source_id = b_timeout_add( global.conf->ping_interval * 1000, irc_userping, irc );
        
        irc_write( irc, ":%s NOTICE AUTH :%s", irc->myhost, "BitlBee-IRCd initialized, please go on" );

        irc_connection_list = g_slist_append( irc_connection_list, irc );
        
        set_add( &irc->set, "away_devoice", "true",  set_eval_away_devoice, irc );
        set_add( &irc->set, "auto_connect", "true", set_eval_bool, irc );
        set_add( &irc->set, "auto_reconnect", "false", set_eval_bool, irc );
        set_add( &irc->set, "auto_reconnect_delay", "300", set_eval_int, irc );
        set_add( &irc->set, "buddy_sendbuffer", "false", set_eval_bool, irc );
        set_add( &irc->set, "buddy_sendbuffer_delay", "200", set_eval_int, irc );
        set_add( &irc->set, "charset", "utf-8", set_eval_charset, irc );
        set_add( &irc->set, "debug", "false", set_eval_bool, irc );
        set_add( &irc->set, "default_target", "root", NULL, irc );
        set_add( &irc->set, "display_namechanges", "false", set_eval_bool, irc );
        set_add( &irc->set, "handle_unknown", "root", NULL, irc );
        set_add( &irc->set, "lcnicks", "true", set_eval_bool, irc );
        set_add( &irc->set, "ops", "both", set_eval_ops, irc );
        set_add( &irc->set, "password", NULL, passchange, irc );
        set_add( &irc->set, "private", "true", set_eval_bool, irc );
        set_add( &irc->set, "query_order", "lifo", NULL, irc );
        set_add( &irc->set, "save_on_quit", "true", set_eval_bool, irc );
        set_add( &irc->set, "simulate_netsplit", "true", set_eval_bool, irc );
        set_add( &irc->set, "strip_html", "true", NULL, irc );
        set_add( &irc->set, "to_char", ": ", set_eval_to_char, irc );
        set_add( &irc->set, "typing_notice", "false", set_eval_bool, irc );
        
        conf_loaddefaults( irc );
        
        return( irc );
}

/* immed=1 makes this function pretty much equal to irc_free(), except that
   this one will "log". In case the connection is already broken and we
   shouldn't try to write to it. */
void irc_abort( irc_t *irc, int immed, char *format, ... )
{
        if( format != NULL )
        {
                va_list params;
                char *reason;
                
                va_start( params, format );
                reason = g_strdup_vprintf( format, params );
                va_end( params );
                
                if( !immed )
                        irc_write( irc, "ERROR :Closing link: %s", reason );
                
                ipc_to_master_str( "OPERMSG :Client exiting: %s@%s [%s]\r\n",
                                   irc->nick ? irc->nick : "(NONE)", irc->host, reason );
                
                g_free( reason );
        }
        else
        {
                if( !immed )
                        irc_write( irc, "ERROR :Closing link" );
                
                ipc_to_master_str( "OPERMSG :Client exiting: %s@%s [%s]\r\n",
                                   irc->nick ? irc->nick : "(NONE)", irc->host, "No reason given" );
        }
        
        irc->status |= USTATUS_SHUTDOWN;
        if( irc->sendbuffer && !immed )
        {
                /* We won't read from this socket anymore. Instead, we'll connect a timer
                   to it that should shut down the connection in a second, just in case
                   bitlbee_.._write doesn't do it first. */
                
                b_event_remove( irc->r_watch_source_id );
                irc->r_watch_source_id = b_timeout_add( 1000, (b_event_handler) irc_free, irc );
        }
        else
        {
                irc_free( irc );
        }
}

static gboolean irc_free_hashkey( gpointer key, gpointer value, gpointer data )
{
        g_free( key );
        
        return( TRUE );
}

/* Because we have no garbage collection, this is quite annoying */
void irc_free(irc_t * irc)
{
        account_t *account;
        user_t *user, *usertmp;
        help_t *helpnode, *helpnodetmp;
        
        log_message( LOGLVL_INFO, "Destroying connection with fd %d", irc->fd );
        
        if( irc->status & USTATUS_IDENTIFIED && set_getbool( &irc->set, "save_on_quit" ) ) 
                if( storage_save( irc, TRUE ) != STORAGE_OK )
                        irc_usermsg( irc, "Error while saving settings!" );
        
        closesocket( irc->fd );
        
        if( irc->ping_source_id > 0 )
                b_event_remove( irc->ping_source_id );
        b_event_remove( irc->r_watch_source_id );
        if( irc->w_watch_source_id > 0 )
                b_event_remove( irc->w_watch_source_id );
        
        irc_connection_list = g_slist_remove( irc_connection_list, irc );
        
        for (account = irc->accounts; account; account = account->next) {
                if (account->ic) {
                        imc_logout(account->ic, TRUE);
                } else if (account->reconnect) {
                        cancel_auto_reconnect(account);
                }
        }
        
        g_free(irc->sendbuffer);
        g_free(irc->readbuffer);
        
        g_free(irc->nick);
        g_free(irc->user);
        g_free(irc->host);
        g_free(irc->realname);
        g_free(irc->password);
        
        g_free(irc->myhost);
        g_free(irc->mynick);
        
        g_free(irc->channel);
        
        while (irc->queries != NULL)
                query_del(irc, irc->queries);
        
        while (irc->accounts)
                if (irc->accounts->ic == NULL)
                        account_del(irc, irc->accounts);
                else
                        /* Nasty hack, but account_del() doesn't work in this
                           case and we don't want infinite loops, do we? ;-) */
                        irc->accounts = irc->accounts->next;
        
        while (irc->set)
                set_del(&irc->set, irc->set->key);
        
        if (irc->users != NULL) {
                user = irc->users;
                while (user != NULL) {
                        g_free(user->nick);
                        g_free(user->away);
                        g_free(user->handle);
                        if(user->user!=user->nick) g_free(user->user);
                        if(user->host!=user->nick) g_free(user->host);
                        if(user->realname!=user->nick) g_free(user->realname);
                        b_event_remove(user->sendbuf_timer);
                                        
                        usertmp = user;
                        user = user->next;
                        g_free(usertmp);
                }
        }
        
        g_hash_table_foreach_remove(irc->userhash, irc_free_hashkey, NULL);
        g_hash_table_destroy(irc->userhash);
        
        g_hash_table_foreach_remove(irc->watches, irc_free_hashkey, NULL);
        g_hash_table_destroy(irc->watches);
        
        if (irc->help != NULL) {
                helpnode = irc->help;
                while (helpnode != NULL) {
                        g_free(helpnode->string);
                        
                        helpnodetmp = helpnode;
                        helpnode = helpnode->next;
                        g_free(helpnodetmp);
                }
        }
        g_free(irc);
        
        if( global.conf->runmode == RUNMODE_INETD || global.conf->runmode == RUNMODE_FORKDAEMON )
                b_main_quit();
}

/* USE WITH CAUTION!
   Sets pass without checking */
void irc_setpass (irc_t *irc, const char *pass) 
{
        g_free (irc->password);
        
        if (pass) {
                irc->password = g_strdup (pass);
        } else {
                irc->password = NULL;
        }
}

void irc_process( irc_t *irc )
{
        char **lines, *temp, **cmd, *cs;
        int i;

        if( irc->readbuffer != NULL )
        {
                lines = irc_tokenize( irc->readbuffer );
                
                for( i = 0; *lines[i] != '\0'; i ++ )
                {
                        char conv[IRC_MAX_LINE+1];
                        
                        /* [WvG] Because irc_tokenize splits at every newline, the lines[] list
                            should end with an empty string. This is why this actually works.
                            Took me a while to figure out, Maurits. :-P */
                        if( lines[i+1] == NULL )
                        {
                                temp = g_strdup( lines[i] );
                                g_free( irc->readbuffer );
                                irc->readbuffer = temp;
                                i ++;
                                break;
                        }
                        
                        if( ( cs = set_getstr( &irc->set, "charset" ) ) )
                        {
                                conv[IRC_MAX_LINE] = 0;
                                if( do_iconv( cs, "UTF-8", lines[i], conv, 0, IRC_MAX_LINE - 2 ) == -1 )
                                {
                                        if( irc->status & USTATUS_LOGGED_IN )
                                                irc_usermsg( irc, "Error: Charset mismatch detected. The charset "
                                                                  "setting is currently set to %s, so please make "
                                                                  "sure your IRC client will send and accept text in "
                                                                  "that charset, or tell BitlBee which charset to "
                                                                  "expect by changing the charset setting. See "
                                                                  "`help set charset' for more information. Your "
                                                                  "message was ignored.", cs );
                                        *conv = 0;
                                }
                                lines[i] = conv;
                        }
                        
                        if( ( cmd = irc_parse_line( lines[i] ) ) == NULL )
                                continue;
                        irc_exec( irc, cmd );
                        
                        g_free( cmd );
                        
                        /* Shouldn't really happen, but just in case... */
                        if( !g_slist_find( irc_connection_list, irc ) )
                        {
                                g_free( lines );
                                return;
                        }
                }
                
                if( lines[i] != NULL )
                {
                        g_free( irc->readbuffer );
                        irc->readbuffer = NULL;
                }
                
                g_free( lines );
        }
}

/* Splits a long string into separate lines. The array is NULL-terminated and, unless the string
   contains an incomplete line at the end, ends with an empty string. */
char **irc_tokenize( char *buffer )
{
        int i, j;
        char **lines;

        /* Count the number of elements we're gonna need. */
        for( i = 0, j = 1; buffer[i] != '\0'; i ++ )
        {
                if( buffer[i] == '\n' )
                        if( buffer[i+1] != '\r' && buffer[i+1] != '\n' )
                                j ++;
        }
        
        /* Allocate j+1 elements. */
        lines = g_new( char *, j + 1 );
        
        /* NULL terminate our list. */ 
        lines[j] = NULL;
        
        lines[0] = buffer;
        
        /* Split the buffer in several strings, using \r\n as our seperator, where \r is optional.
         * Although this is not in the RFC, some braindead ircds (newnet's) use this, so some clients might too. 
         */
        for( i = 0, j = 0; buffer[i] != '\0'; i ++)
        {
                if( buffer[i] == '\n' )
                {
                        buffer[i] = '\0';
                        
                        if( i > 0 && buffer[i-1] == '\r' )
                                buffer[i-1] = '\0';
                        if( buffer[i+1] != '\r' && buffer[i+1] != '\n' )
                                lines[++j] = buffer + i + 1;
                }
        }
        
        return( lines );
}

/* Split an IRC-style line into little parts/arguments. */
char **irc_parse_line( char *line )
{
        int i, j;
        char **cmd;
        
        /* Move the line pointer to the start of the command, skipping spaces and the optional prefix. */
        if( line[0] == ':' )
        {
                for( i = 0; line[i] != ' '; i ++ );
                line = line + i;
        }
        for( i = 0; line[i] == ' '; i ++ );
        line = line + i;
        
        /* If we're already at the end of the line, return. If not, we're going to need at least one element. */
        if( line[0] == '\0')
                return NULL;
        
        /* Count the number of char **cmd elements we're going to need. */
        j = 1;
        for( i = 0; line[i] != '\0'; i ++ )
        {
                if( line[i] == ' ' )
                {
                        j ++;
                        
                        if( line[i+1] == ':' )
                                break;
                }
        }       

        /* Allocate the space we need. */
        cmd = g_new( char *, j + 1 );
        cmd[j] = NULL;
        
        /* Do the actual line splitting, format is:
         * Input: "PRIVMSG #bitlbee :foo bar"
         * Output: cmd[0]=="PRIVMSG", cmd[1]=="#bitlbee", cmd[2]=="foo bar", cmd[3]==NULL
         */

        cmd[0] = line;
        for( i = 0, j = 0; line[i] != '\0'; i ++ )
        {
                if( line[i] == ' ' )
                {
                        line[i] = '\0';
                        cmd[++j] = line + i + 1;
                        
                        if( line[i+1] == ':' )
                        {
                                cmd[j] ++;
                                break;
                        }
                }
        }
        
        return cmd;
}

/* Converts such an array back into a command string. Mainly used for the IPC code right now. */
char *irc_build_line( char **cmd )
{
        int i, len;
        char *s;
        
        if( cmd[0] == NULL )
                return NULL;
        
        len = 1;
        for( i = 0; cmd[i]; i ++ )
                len += strlen( cmd[i] ) + 1;
        
        if( strchr( cmd[i-1], ' ' ) != NULL )
                len ++;
        
        s = g_new0( char, len + 1 );
        for( i = 0; cmd[i]; i ++ )
        {
                if( cmd[i+1] == NULL && strchr( cmd[i], ' ' ) != NULL )
                        strcat( s, ":" );
                
                strcat( s, cmd[i] );
                
                if( cmd[i+1] )
                        strcat( s, " " );
        }
        strcat( s, "\r\n" );
        
        return s;
}

void irc_reply( irc_t *irc, int code, char *format, ... )
{
        char text[IRC_MAX_LINE];
        va_list params;
        
        va_start( params, format );
        g_vsnprintf( text, IRC_MAX_LINE, format, params );
        va_end( params );
        irc_write( irc, ":%s %03d %s %s", irc->myhost, code, irc->nick?irc->nick:"*", text );
        
        return;
}

int irc_usermsg( irc_t *irc, char *format, ... )
{
        char text[1024];
        va_list params;
        char is_private = 0;
        user_t *u;
        
        u = user_find( irc, irc->mynick );
        is_private = u->is_private;
        
        va_start( params, format );
        g_vsnprintf( text, sizeof( text ), format, params );
        va_end( params );
        
        return( irc_msgfrom( irc, u->nick, text ) );
}

void irc_write( irc_t *irc, char *format, ... ) 
{
        va_list params;

        va_start( params, format );
        irc_vawrite( irc, format, params );     
        va_end( params );

        return;

}

void irc_vawrite( irc_t *irc, char *format, va_list params )
{
        int size;
        char line[IRC_MAX_LINE+1], *cs;
                
        /* Don't try to write anything new anymore when shutting down. */
        if( irc->status & USTATUS_SHUTDOWN )
                return;
        
        line[IRC_MAX_LINE] = 0;
        g_vsnprintf( line, IRC_MAX_LINE - 2, format, params );
        
        strip_newlines( line );
        if( ( cs = set_getstr( &irc->set, "charset" ) ) && ( g_strcasecmp( cs, "utf-8" ) != 0 ) )
        {
                char conv[IRC_MAX_LINE+1];
                
                conv[IRC_MAX_LINE] = 0;
                if( do_iconv( "UTF-8", cs, line, conv, 0, IRC_MAX_LINE - 2 ) != -1 )
                        strcpy( line, conv );
        }
        strcat( line, "\r\n" );
        
        if( irc->sendbuffer != NULL )
        {
                size = strlen( irc->sendbuffer ) + strlen( line );
                irc->sendbuffer = g_renew ( char, irc->sendbuffer, size + 1 );
                strcpy( ( irc->sendbuffer + strlen( irc->sendbuffer ) ), line );
        }
        else
        {
                irc->sendbuffer = g_strdup(line);
        }
        
        if( irc->w_watch_source_id == 0 )
        {
                /* If the buffer is empty we can probably write, so call the write event handler
                   immediately. If it returns TRUE, it should be called again, so add the event to
                   the queue. If it's FALSE, we emptied the buffer and saved ourselves some work
                   in the event queue. */
                /* Really can't be done as long as the code doesn't do error checking very well:
                if( bitlbee_io_current_client_write( irc, irc->fd, GAIM_INPUT_WRITE ) ) */
                
                /* So just always do it via the event handler. */
                irc->w_watch_source_id = b_input_add( irc->fd, GAIM_INPUT_WRITE, bitlbee_io_current_client_write, irc );
        }
        
        return;
}

void irc_write_all( int now, char *format, ... )
{
        va_list params;
        GSList *temp;   
        
        va_start( params, format );
        
        temp = irc_connection_list;
        while( temp != NULL )
        {
                irc_t *irc = temp->data;
                
                if( now )
                {
                        g_free( irc->sendbuffer );
                        irc->sendbuffer = g_strdup( "\r\n" );
                }
                irc_vawrite( temp->data, format, params );
                if( now )
                {
                        bitlbee_io_current_client_write( irc, irc->fd, GAIM_INPUT_WRITE );
                }
                temp = temp->next;
        }
        
        va_end( params );
        return;
} 

void irc_names( irc_t *irc, char *channel )
{
        user_t *u;
        char namelist[385] = "";
        struct groupchat *c = NULL;
        char *ops = set_getstr( &irc->set, "ops" );
        
        /* RFCs say there is no error reply allowed on NAMES, so when the
           channel is invalid, just give an empty reply. */
        
        if( g_strcasecmp( channel, irc->channel ) == 0 )
        {
                for( u = irc->users; u; u = u->next ) if( u->online )
                {
                        if( strlen( namelist ) + strlen( u->nick ) > sizeof( namelist ) - 4 )
                        {
                                irc_reply( irc, 353, "= %s :%s", channel, namelist );
                                *namelist = 0;
                        }
                        
                        if( u->ic && !u->away && set_getbool( &irc->set, "away_devoice" ) )
                                strcat( namelist, "+" );
                        else if( ( strcmp( u->nick, irc->mynick ) == 0 && ( strcmp( ops, "root" ) == 0 || strcmp( ops, "both" ) == 0 ) ) ||
                                 ( strcmp( u->nick, irc->nick ) == 0 && ( strcmp( ops, "user" ) == 0 || strcmp( ops, "both" ) == 0 ) ) )
                                strcat( namelist, "@" );
                        
                        strcat( namelist, u->nick );
                        strcat( namelist, " " );
                }
        }
        else if( ( c = irc_chat_by_channel( irc, channel ) ) )
        {
                GList *l;
                
                /* root and the user aren't in the channel userlist but should
                   show up in /NAMES, so list them first: */
                sprintf( namelist, "%s%s %s%s ", strcmp( ops, "root" ) == 0 || strcmp( ops, "both" ) ? "@" : "", irc->mynick,
                                                 strcmp( ops, "user" ) == 0 || strcmp( ops, "both" ) ? "@" : "", irc->nick );
                
                for( l = c->in_room; l; l = l->next ) if( ( u = user_findhandle( c->ic, l->data ) ) )
                {
                        if( strlen( namelist ) + strlen( u->nick ) > sizeof( namelist ) - 4 )
                        {
                                irc_reply( irc, 353, "= %s :%s", channel, namelist );
                                *namelist = 0;
                        }
                        
                        strcat( namelist, u->nick );
                        strcat( namelist, " " );
                }
        }
        
        if( *namelist )
                irc_reply( irc, 353, "= %s :%s", channel, namelist );
        
        irc_reply( irc, 366, "%s :End of /NAMES list", channel );
}

int irc_check_login( irc_t *irc )
{
        if( irc->user && irc->nick )
        {
                if( global.conf->authmode == AUTHMODE_CLOSED && !( irc->status & USTATUS_AUTHORIZED ) )
                {
                        irc_reply( irc, 464, ":This server is password-protected." );
                        return 0;
                }
                else
                {
                        irc_login( irc );
                        return 1;
                }
        }
        else
        {
                /* More information needed. */
                return 0;
        }
}

void irc_login( irc_t *irc )
{
        user_t *u;
        
        irc_reply( irc,   1, ":Welcome to the BitlBee gateway, %s", irc->nick );
        irc_reply( irc,   2, ":Host %s is running BitlBee " BITLBEE_VERSION " " ARCH "/" CPU ".", irc->myhost );
        irc_reply( irc,   3, ":%s", IRCD_INFO );
        irc_reply( irc,   4, "%s %s %s %s", irc->myhost, BITLBEE_VERSION, UMODES UMODES_PRIV, CMODES );
        irc_reply( irc,   5, "PREFIX=(ov)@+ CHANTYPES=#& CHANMODES=,,,%s NICKLEN=%d NETWORK=BitlBee CASEMAPPING=rfc1459 MAXTARGETS=1 WATCH=128 :are supported by this server", CMODES, MAX_NICK_LENGTH - 1 );
        irc_motd( irc );
        irc->umode[0] = '\0';
        irc_umode_set( irc, "+" UMODE, 1 );

        u = user_add( irc, irc->mynick );
        u->host = g_strdup( irc->myhost );
        u->realname = g_strdup( ROOT_FN );
        u->online = 1;
        u->send_handler = root_command_string;
        u->is_private = 0; /* [SH] The channel is root's personal playground. */
        irc_spawn( irc, u );
        
        u = user_add( irc, NS_NICK );
        u->host = g_strdup( irc->myhost );
        u->realname = g_strdup( ROOT_FN );
        u->online = 0;
        u->send_handler = root_command_string;
        u->is_private = 1; /* [SH] NickServ is not in the channel, so should always /query. */
        
        u = user_add( irc, irc->nick );
        u->user = g_strdup( irc->user );
        u->host = g_strdup( irc->host );
        u->realname = g_strdup( irc->realname );
        u->online = 1;
        irc_spawn( irc, u );
        
        irc_usermsg( irc, "Welcome to the BitlBee gateway!\n\nIf you've never used BitlBee before, please do read the help information using the \x02help\x02 command. Lots of FAQs are answered there." );
        
        if( global.conf->runmode == RUNMODE_FORKDAEMON || global.conf->runmode == RUNMODE_DAEMON )
                ipc_to_master_str( "CLIENT %s %s :%s\r\n", irc->host, irc->nick, irc->realname );
        
        irc->status |= USTATUS_LOGGED_IN;
}

void irc_motd( irc_t *irc )
{
        int fd;
        
        fd = open( global.conf->motdfile, O_RDONLY );
        if( fd == -1 )
        {
                irc_reply( irc, 422, ":We don't need MOTDs." );
        }
        else
        {
                char linebuf[80];       /* Max. line length for MOTD's is 79 chars. It's what most IRC networks seem to do. */
                char *add, max;
                int len;
                
                linebuf[79] = len = 0;
                max = sizeof( linebuf ) - 1;
                
                irc_reply( irc, 375, ":- %s Message Of The Day - ", irc->myhost );
                while( read( fd, linebuf + len, 1 ) == 1 )
                {
                        if( linebuf[len] == '\n' || len == max )
                        {
                                linebuf[len] = 0;
                                irc_reply( irc, 372, ":- %s", linebuf );
                                len = 0;
                        }
                        else if( linebuf[len] == '%' )
                        {
                                read( fd, linebuf + len, 1 );
                                if( linebuf[len] == 'h' )
                                        add = irc->myhost;
                                else if( linebuf[len] == 'v' )
                                        add = BITLBEE_VERSION;
                                else if( linebuf[len] == 'n' )
                                        add = irc->nick;
                                else
                                        add = "%";
                                
                                strncpy( linebuf + len, add, max - len );
                                while( linebuf[++len] );
                        }
                        else if( len < max )
                        {
                                len ++;
                        }
                }
                irc_reply( irc, 376, ":End of MOTD" );
                close( fd );
        }
}

void irc_topic( irc_t *irc, char *channel )
{
        struct groupchat *c = irc_chat_by_channel( irc, channel );
        
        if( c && c->topic )
                irc_reply( irc, 332, "%s :%s", channel, c->topic );
        else if( g_strcasecmp( channel, irc->channel ) == 0 )
                irc_reply( irc, 332, "%s :%s", channel, CONTROL_TOPIC );
        else
                irc_reply( irc, 331, "%s :No topic for this channel", channel );
}

void irc_umode_set( irc_t *irc, char *s, int allow_priv )
{
        /* allow_priv: Set to 0 if s contains user input, 1 if you want
           to set a "privileged" mode (+o, +R, etc). */
        char m[256], st = 1, *t;
        int i;
        char changes[512], *p, st2 = 2;
        char badflag = 0;
        
        memset( m, 0, sizeof( m ) );
        
        for( t = irc->umode; *t; t ++ )
                m[(int)*t] = 1;

        p = changes;
        for( t = s; *t; t ++ )
        {
                if( *t == '+' || *t == '-' )
                        st = *t == '+';
                else if( st == 0 || ( strchr( UMODES, *t ) || ( allow_priv && strchr( UMODES_PRIV, *t ) ) ) )
                {
                        if( m[(int)*t] != st)
                        {
                                if( st != st2 )
                                        st2 = st, *p++ = st ? '+' : '-';
                                *p++ = *t;
                        }
                        m[(int)*t] = st;
                }
                else
                        badflag = 1;
        }
        *p = '\0';
        
        memset( irc->umode, 0, sizeof( irc->umode ) );
        
        for( i = 0; i < 256 && strlen( irc->umode ) < ( sizeof( irc->umode ) - 1 ); i ++ )
                if( m[i] )
                        irc->umode[strlen(irc->umode)] = i;
        
        if( badflag )
                irc_reply( irc, 501, ":Unknown MODE flag" );
        /* Deliberately no !user@host on the prefix here */
        if( *changes )
                irc_write( irc, ":%s MODE %s %s", irc->nick, irc->nick, changes );
}

void irc_spawn( irc_t *irc, user_t *u )
{
        irc_join( irc, u, irc->channel );
}

void irc_join( irc_t *irc, user_t *u, char *channel )
{
        char *nick;
        
        if( ( g_strcasecmp( channel, irc->channel ) != 0 ) || user_find( irc, irc->nick ) )
                irc_write( irc, ":%s!%s@%s JOIN :%s", u->nick, u->user, u->host, channel );
        
        if( nick_cmp( u->nick, irc->nick ) == 0 )
        {
                irc_write( irc, ":%s MODE %s +%s", irc->myhost, channel, CMODE );
                irc_names( irc, channel );
                irc_topic( irc, channel );
        }
        
        nick = g_strdup( u->nick );
        nick_lc( nick );
        if( g_hash_table_lookup( irc->watches, nick ) )
        {
                irc_reply( irc, 600, "%s %s %s %d :%s", u->nick, u->user, u->host, (int) time( NULL ), "logged online" );
        }
        g_free( nick );
}

void irc_part( irc_t *irc, user_t *u, char *channel )
{
        irc_write( irc, ":%s!%s@%s PART %s :%s", u->nick, u->user, u->host, channel, "" );
}

void irc_kick( irc_t *irc, user_t *u, char *channel, user_t *kicker )
{
        irc_write( irc, ":%s!%s@%s KICK %s %s :%s", kicker->nick, kicker->user, kicker->host, channel, u->nick, "" );
}

void irc_kill( irc_t *irc, user_t *u )
{
        char *nick, *s;
        char reason[128];
        
        if( u->ic && u->ic->flags & OPT_LOGGING_OUT && set_getbool( &irc->set, "simulate_netsplit" ) )
        {
                if( u->ic->acc->server )
                        g_snprintf( reason, sizeof( reason ), "%s %s", irc->myhost,
                                    u->ic->acc->server );
                else if( ( s = strchr( u->ic->acc->user, '@' ) ) )
                        g_snprintf( reason, sizeof( reason ), "%s %s", irc->myhost,
                                    s + 1 );
                else
                        g_snprintf( reason, sizeof( reason ), "%s %s.%s", irc->myhost,
                                    u->ic->acc->prpl->name, irc->myhost );
                
                /* proto_opt might contain garbage after the : */
                if( ( s = strchr( reason, ':' ) ) )
                        *s = 0;
        }
        else
        {
                strcpy( reason, "Leaving..." );
        }
        
        irc_write( irc, ":%s!%s@%s QUIT :%s", u->nick, u->user, u->host, reason );
        
        nick = g_strdup( u->nick );
        nick_lc( nick );
        if( g_hash_table_lookup( irc->watches, nick ) )
        {
                irc_reply( irc, 601, "%s %s %s %d :%s", u->nick, u->user, u->host, (int) time( NULL ), "logged offline" );
        }
        g_free( nick );
}

int irc_send( irc_t *irc, char *nick, char *s, int flags )
{
        struct groupchat *c = NULL;
        user_t *u = NULL;
        
        if( *nick == '#' || *nick == '&' )
        {
                if( !( c = irc_chat_by_channel( irc, nick ) ) )
                {
                        irc_reply( irc, 403, "%s :Channel does not exist", nick );
                        return( 0 );
                }
        }
        else
        {
                u = user_find( irc, nick );
                
                if( !u )
                {
                        if( irc->is_private )
                                irc_reply( irc, 401, "%s :Nick does not exist", nick );
                        else
                                irc_usermsg( irc, "Nick `%s' does not exist!", nick );
                        return( 0 );
                }
        }
        
        if( *s == 1 && s[strlen(s)-1] == 1 )
        {
                if( g_strncasecmp( s + 1, "ACTION", 6 ) == 0 )
                {
                        if( s[7] == ' ' ) s ++;
                        s += 3;
                        *(s++) = '/';
                        *(s++) = 'm';
                        *(s++) = 'e';
                        *(s++) = ' ';
                        s -= 4;
                        s[strlen(s)-1] = 0;
                }
                else if( g_strncasecmp( s + 1, "VERSION", 7 ) == 0 )
                {
                        u = user_find( irc, irc->mynick );
                        irc_privmsg( irc, u, "NOTICE", irc->nick, "", "\001VERSION BitlBee " BITLBEE_VERSION " " ARCH "/" CPU "\001" );
                        return( 1 );
                }
                else if( g_strncasecmp( s + 1, "PING", 4 ) == 0 )
                {
                        u = user_find( irc, irc->mynick );
                        irc_privmsg( irc, u, "NOTICE", irc->nick, "", s );
                        return( 1 );
                }
                else if( g_strncasecmp( s + 1, "TYPING", 6 ) == 0 )
                {
                        if( u && u->ic && u->ic->acc->prpl->send_typing && strlen( s ) >= 10 )
                        {
                                time_t current_typing_notice = time( NULL );
                                
                                if( current_typing_notice - u->last_typing_notice >= 5 )
                                {
                                        u->ic->acc->prpl->send_typing( u->ic, u->handle, ( s[8] - '0' ) << 8 );
                                        u->last_typing_notice = current_typing_notice;
                                }
                        }
                        return( 1 );
                }
                else
                {
                        irc_usermsg( irc, "Non-ACTION CTCP's aren't supported" );
                        return( 0 );
                }
        }
        
        if( u )
        {
                /* For the next message, we probably do have to send new notices... */
                u->last_typing_notice = 0;
                u->is_private = irc->is_private;
                
                if( u->is_private )
                {
                        if( !u->online )
                                irc_reply( irc, 301, "%s :%s", u->nick, "User is offline" );
                        else if( u->away )
                                irc_reply( irc, 301, "%s :%s", u->nick, u->away );
                }
                
                if( u->send_handler )
                {
                        u->send_handler( irc, u, s, flags );
                        return 1;
                }
        }
        else if( c && c->ic && c->ic->acc && c->ic->acc->prpl )
        {
                return( imc_chat_msg( c, s, 0 ) );
        }
        
        return( 0 );
}

static gboolean buddy_send_handler_delayed( gpointer data, gint fd, b_input_condition cond )
{
        user_t *u = data;
        
        /* Shouldn't happen, but just to be sure. */
        if( u->sendbuf_len < 2 )
                return FALSE;
        
        u->sendbuf[u->sendbuf_len-2] = 0; /* Cut off the last newline */
        imc_buddy_msg( u->ic, u->handle, u->sendbuf, u->sendbuf_flags );
        
        g_free( u->sendbuf );
        u->sendbuf = NULL;
        u->sendbuf_len = 0;
        u->sendbuf_timer = 0;
        u->sendbuf_flags = 0;
        
        return FALSE;
}

void buddy_send_handler( irc_t *irc, user_t *u, char *msg, int flags )
{
        if( !u || !u->ic ) return;
        
        if( set_getbool( &irc->set, "buddy_sendbuffer" ) && set_getint( &irc->set, "buddy_sendbuffer_delay" ) > 0 )
        {
                int delay;
                
                if( u->sendbuf_len > 0 && u->sendbuf_flags != flags)
                {
                        /* Flush the buffer */
                        b_event_remove( u->sendbuf_timer );
                        buddy_send_handler_delayed( u, -1, 0 );
                }

                if( u->sendbuf_len == 0 )
                {
                        u->sendbuf_len = strlen( msg ) + 2;
                        u->sendbuf = g_new( char, u->sendbuf_len );
                        u->sendbuf[0] = 0;
                        u->sendbuf_flags = flags;
                }
                else
                {
                        u->sendbuf_len += strlen( msg ) + 1;
                        u->sendbuf = g_renew( char, u->sendbuf, u->sendbuf_len );
                }
                
                strcat( u->sendbuf, msg );
                strcat( u->sendbuf, "\n" );
                
                delay = set_getint( &irc->set, "buddy_sendbuffer_delay" );
                if( delay <= 5 )
                        delay *= 1000;
                
                if( u->sendbuf_timer > 0 )
                        b_event_remove( u->sendbuf_timer );
                u->sendbuf_timer = b_timeout_add( delay, buddy_send_handler_delayed, u );
        }
        else
        {
                imc_buddy_msg( u->ic, u->handle, msg, flags );
        }
}

int irc_privmsg( irc_t *irc, user_t *u, char *type, char *to, char *prefix, char *msg )
{
        char last = 0;
        char *s = msg, *line = msg;
        
        /* The almighty linesplitter .. woohoo!! */
        while( !last )
        {
                if( *s == '\r' && *(s+1) == '\n' )
                        *(s++) = 0;
                if( *s == '\n' )
                {
                        last = s[1] == 0;
                        *s = 0;
                }
                else
                {
                        last = s[0] == 0;
                }
                if( *s == 0 )
                {
                        if( g_strncasecmp( line, "/me ", 4 ) == 0 && ( !prefix || !*prefix ) && g_strcasecmp( type, "PRIVMSG" ) == 0 )
                        {
                                irc_write( irc, ":%s!%s@%s %s %s :\001ACTION %s\001", u->nick, u->user, u->host,
                                           type, to, line + 4 );
                        }
                        else
                        {
                                irc_write( irc, ":%s!%s@%s %s %s :%s%s", u->nick, u->user, u->host,
                                           type, to, prefix ? prefix : "", line );
                        }
                        line = s + 1;
                }
                s ++;
        }
        
        return( 1 );
}

int irc_msgfrom( irc_t *irc, char *nick, char *msg )
{
        user_t *u = user_find( irc, nick );
        static char *prefix = NULL;
        
        if( !u ) return( 0 );
        if( prefix && *prefix ) g_free( prefix );
        
        if( !u->is_private && nick_cmp( u->nick, irc->mynick ) != 0 )
        {
                int len = strlen( irc->nick) + 3;
                prefix = g_new (char, len );
                g_snprintf( prefix, len, "%s%s", irc->nick, set_getstr( &irc->set, "to_char" ) );
                prefix[len-1] = 0;
        }
        else
        {
                prefix = "";
        }
        
        return( irc_privmsg( irc, u, "PRIVMSG", u->is_private ? irc->nick : irc->channel, prefix, msg ) );
}

int irc_noticefrom( irc_t *irc, char *nick, char *msg )
{
        user_t *u = user_find( irc, nick );
        
        if( u )
                return( irc_privmsg( irc, u, "NOTICE", irc->nick, "", msg ) );
        else
                return( 0 );
}

/* Returns 0 if everything seems to be okay, a number >0 when there was a
   timeout. The number returned is the number of seconds we received no
   pongs from the user. When not connected yet, we don't ping but drop the
   connection when the user fails to connect in IRC_LOGIN_TIMEOUT secs. */
static gboolean irc_userping( gpointer _irc, gint fd, b_input_condition cond )
{
        irc_t *irc = _irc;
        int rv = 0;
        
        if( !( irc->status & USTATUS_LOGGED_IN ) )
        {
                if( gettime() > ( irc->last_pong + IRC_LOGIN_TIMEOUT ) )
                        rv = gettime() - irc->last_pong;
        }
        else
        {
                if( ( gettime() > ( irc->last_pong + global.conf->ping_interval ) ) && !irc->pinging )
                {
                        irc_write( irc, "PING :%s", IRC_PING_STRING );
                        irc->pinging = 1;
                }
                else if( gettime() > ( irc->last_pong + global.conf->ping_timeout ) )
                {
                        rv = gettime() - irc->last_pong;
                }
        }
        
        if( rv > 0 )
        {
                irc_abort( irc, 0, "Ping Timeout: %d seconds", rv );
                return FALSE;
        }
        
        return TRUE;
}

struct groupchat *irc_chat_by_channel( irc_t *irc, char *channel )
{
        struct groupchat *c;
        account_t *a;
        
        /* This finds the connection which has a conversation which belongs to this channel */
        for( a = irc->accounts; a; a = a->next )
        {
                if( a->ic == NULL )
                        continue;
                
                c = a->ic->groupchats;
                while( c )
                {
                        if( c->channel && g_strcasecmp( c->channel, channel ) == 0 )
                                return c;
                        
                        c = c->next;
                }
        }
        
        return NULL;
}