source: nick.c @ 5674207

  /********************************************************************\
  * BitlBee -- An IRC to other IM-networks gateway                     *
  *                                                                    *
  * Copyright 2002-2007 Wilmer van der Gaast and others                *
  \********************************************************************/

/* Some stuff to fetch, save and handle nicknames for your buddies      */

/*
  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"

/* Store handles in lower case and strip spaces, because AIM is braindead. */
static char *clean_handle( const char *orig )
{
        char *new = g_malloc( strlen( orig ) + 1 );
        int i = 0;
        
        do {
                if (*orig != ' ')
                        new[i++] = tolower( *orig );
        }
        while (*(orig++));
        
        return new;
}

void nick_set( account_t *acc, const char *handle, const char *nick )
{
        char *store_handle, *store_nick = g_malloc( MAX_NICK_LENGTH + 1 );
        
        store_handle = clean_handle( handle );
        store_nick[MAX_NICK_LENGTH] = 0;
        strncpy( store_nick, nick, MAX_NICK_LENGTH );
        nick_strip( store_nick );
        
        g_hash_table_replace( acc->nicks, store_handle, store_nick );
}

char *nick_get( account_t *acc, const char *handle )
{
        static char nick[MAX_NICK_LENGTH+1];
        char *store_handle, *found_nick;
        
        memset( nick, 0, MAX_NICK_LENGTH + 1 );
        
        store_handle = clean_handle( handle );
        /* Find out if we stored a nick for this person already. If not, try
           to generate a sane nick automatically. */
        if( ( found_nick = g_hash_table_lookup( acc->nicks, store_handle ) ) )
        {
                strncpy( nick, found_nick, MAX_NICK_LENGTH );
        }
        else
        {
                char *s;
                
                g_snprintf( nick, MAX_NICK_LENGTH, "%s", handle );
                if( ( s = strchr( nick, '@' ) ) )
                        while( *s )
                                *(s++) = 0;
                
                nick_strip( nick );
                if( set_getbool( &acc->irc->set, "lcnicks" ) )
                        nick_lc( nick );
        }
        g_free( store_handle );
        
        /* Make sure the nick doesn't collide with an existing one by adding
           underscores and that kind of stuff, if necessary. */
        nick_dedupe( acc, handle, nick );
        
        return nick;
}

void nick_dedupe( account_t *acc, const char *handle, char nick[MAX_NICK_LENGTH+1] )
{
        int inf_protection = 256;
        
        /* Now, find out if the nick is already in use at the moment, and make
           subtle changes to make it unique. */
        while( !nick_ok( nick ) || user_find( acc->irc, nick ) )
        {
                if( strlen( nick ) < ( MAX_NICK_LENGTH - 1 ) )
                {
                        nick[strlen(nick)+1] = 0;
                        nick[strlen(nick)] = '_';
                }
                else
                {
                        nick[0] ++;
                }
                
                if( inf_protection-- == 0 )
                {
                        int i;
                        
                        irc_usermsg( acc->irc, "Warning: Almost had an infinite loop in nick_get()! "
                                               "This used to be a fatal BitlBee bug, but we tried to fix it. "
                                               "This message should *never* appear anymore. "
                                               "If it does, please *do* send us a bug report! "
                                               "Please send all the following lines in your report:" );
                        
                        irc_usermsg( acc->irc, "Trying to get a sane nick for handle %s", handle );
                        for( i = 0; i < MAX_NICK_LENGTH; i ++ )
                                irc_usermsg( acc->irc, "Char %d: %c/%d", i, nick[i], nick[i] );
                        
                        irc_usermsg( acc->irc, "FAILED. Returning an insane nick now. Things might break. "
                                               "Good luck, and please don't forget to paste the lines up here "
                                               "in #bitlbee on OFTC or in a mail to wilmer@gaast.net" );
                        
                        g_snprintf( nick, MAX_NICK_LENGTH + 1, "xx%x", rand() );
                        
                        break;
                }
        }
}

/* Just check if there is a nickname set for this buddy or if we'd have to
   generate one. */
int nick_saved( account_t *acc, const char *handle )
{
        char *store_handle, *found;
        
        store_handle = clean_handle( handle );
        found = g_hash_table_lookup( acc->nicks, store_handle );
        g_free( store_handle );
        
        return found != NULL;
}

void nick_del( account_t *acc, const char *handle )
{
        g_hash_table_remove( acc->nicks, handle );
}


/* Character maps, _lc_[x] == _uc_[x] (but uppercase), according to the RFC's.
   With one difference, we allow dashes. */

static char *nick_lc_chars = "0123456789abcdefghijklmnopqrstuvwxyz{}^`-_|";
static char *nick_uc_chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ[]~`-_\\";

void nick_strip( char *nick )
{
        int i, j;
        
        for( i = j = 0; nick[i] && j < MAX_NICK_LENGTH; i++ )
        {
                if( strchr( nick_lc_chars, nick[i] ) || 
                    strchr( nick_uc_chars, nick[i] ) )
                {
                        nick[j] = nick[i];
                        j++;
                }
        }
        if( isdigit( nick[0] ) )
        {
                char *orig;
                
                orig = g_strdup( nick );
                g_snprintf( nick, MAX_NICK_LENGTH, "_%s", orig );
                g_free( orig );
                j ++;
        }
        while( j <= MAX_NICK_LENGTH )
                nick[j++] = '\0';
}

int nick_ok( const char *nick )
{
        const char *s;
        
        /* Empty/long nicks are not allowed, nor numbers at [0] */
        if( !*nick || isdigit( nick[0] ) || strlen( nick ) > MAX_NICK_LENGTH )
                return( 0 );
        
        for( s = nick; *s; s ++ )
                if( !strchr( nick_lc_chars, *s ) && !strchr( nick_uc_chars, *s ) )
                        return( 0 );
        
        return( 1 );
}

int nick_lc( char *nick )
{
        static char tab[128] = { 0 };
        int i;
        
        if( tab['A'] == 0 )
                for( i = 0; nick_lc_chars[i]; i ++ )
                {
                        tab[(int)nick_uc_chars[i]] = nick_lc_chars[i];
                        tab[(int)nick_lc_chars[i]] = nick_lc_chars[i];
                }
        
        for( i = 0; nick[i]; i ++ )
        {
                if( !tab[(int)nick[i]] )
                        return( 0 );
                
                nick[i] = tab[(int)nick[i]];
        }
        
        return( 1 );
}

int nick_uc( char *nick )
{
        static char tab[128] = { 0 };
        int i;
        
        if( tab['A'] == 0 )
                for( i = 0; nick_lc_chars[i]; i ++ )
                {
                        tab[(int)nick_uc_chars[i]] = nick_uc_chars[i];
                        tab[(int)nick_lc_chars[i]] = nick_uc_chars[i];
                }
        
        for( i = 0; nick[i]; i ++ )
        {
                if( !tab[(int)nick[i]] )
                        return( 0 );
                
                nick[i] = tab[(int)nick[i]];
        }
        
        return( 1 );
}

int nick_cmp( const char *a, const char *b )
{
        char aa[1024] = "", bb[1024] = "";
        
        strncpy( aa, a, sizeof( aa ) - 1 );
        strncpy( bb, b, sizeof( bb ) - 1 );
        if( nick_lc( aa ) && nick_lc( bb ) )
        {
                return( strcmp( aa, bb ) );
        }
        else
        {
                return( -1 );   /* Hmm... Not a clear answer.. :-/ */
        }
}

char *nick_dup( const char *nick )
{
        return g_strndup( nick, MAX_NICK_LENGTH );
}