source: nick.c @ eabe6d4

  /********************************************************************\
  * BitlBee -- An IRC to other IM-networks gateway                     *
  *                                                                    *
  * Copyright 2002-2012 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., 51 Franklin St.,
  Fifth Floor, Boston, MA  02110-1301  USA
*/

#define BITLBEE_CORE
#include "bitlbee.h"

/* Character maps, _lc_[x] == _uc_[x] (but uppercase), according to the RFC's.
   With one difference, we allow dashes. These are used to do uc/lc conversions
   and strip invalid chars. */
static char *nick_lc_chars = "0123456789abcdefghijklmnopqrstuvwxyz{}^`-_|";
static char *nick_uc_chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ[]~`-_\\";

/* 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++] = g_ascii_tolower( *orig );
        }
        while (*(orig++));
        
        return new;
}

void nick_set_raw( account_t *acc, const char *handle, const char *nick )
{
        char *store_handle, *store_nick = g_malloc( MAX_NICK_LENGTH + 1 );
        irc_t *irc = (irc_t *) acc->bee->ui_data;
        
        store_handle = clean_handle( handle );
        store_nick[MAX_NICK_LENGTH] = '\0';
        strncpy( store_nick, nick, MAX_NICK_LENGTH );
        nick_strip( irc, store_nick );
        
        g_hash_table_replace( acc->nicks, store_handle, store_nick );
}

void nick_set( bee_user_t *bu, const char *nick )
{
        nick_set_raw( bu->ic->acc, bu->handle, nick );
}

char *nick_get( bee_user_t *bu )
{
        static char nick[MAX_NICK_LENGTH+1];
        char *store_handle, *found_nick;
        irc_t *irc = (irc_t *) bu->bee->ui_data;
        
        memset( nick, 0, MAX_NICK_LENGTH + 1 );
        
        store_handle = clean_handle( bu->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( bu->ic->acc->nicks, store_handle ) ) )
        {
                strncpy( nick, found_nick, MAX_NICK_LENGTH );
        }
        else if( ( found_nick = nick_gen( bu ) ) )
        {
                strncpy( nick, found_nick, MAX_NICK_LENGTH );
                g_free( found_nick );
        }
        else
        {
                /* Keep this fallback since nick_gen() can return NULL in some cases. */
                char *s;
                
                g_snprintf( nick, MAX_NICK_LENGTH, "%s", bu->handle );
                if( ( s = strchr( nick, '@' ) ) )
                        while( *s )
                                *(s++) = 0;
                
                nick_strip( irc, nick );
                if( set_getbool( &bu->bee->set, "lcnicks" ) )
                        nick_lc( irc, 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( bu, nick );
        
        return nick;
}

char *nick_gen( bee_user_t *bu )
{
        gboolean ok = FALSE; /* Set to true once the nick contains something unique. */
        GString *ret = g_string_sized_new( MAX_NICK_LENGTH + 1 );
        char *rets;
        irc_t *irc = (irc_t *) bu->bee->ui_data;
        char *fmt = set_getstr( &bu->ic->acc->set, "nick_format" ) ? :
                    set_getstr( &bu->bee->set, "nick_format" );
        
        while( fmt && *fmt && ret->len < MAX_NICK_LENGTH )
        {
                char *part = NULL, chop = '\0', *asc = NULL, *s;
                int len = INT_MAX;
                
                if( *fmt != '%' )
                {
                        g_string_append_c( ret, *fmt );
                        fmt ++;
                        continue;
                }
                
                fmt ++;
                while( *fmt )
                {
                        /* -char means chop off everything from char */
                        if( *fmt == '-' )
                        {
                                chop = fmt[1];
                                if( chop == '\0' )
                                {
                                        g_string_free( ret, TRUE );
                                        return NULL;
                                }
                                fmt += 2;
                        }
                        else if( g_ascii_isdigit( *fmt ) )
                        {
                                len = 0;
                                /* Grab a number. */
                                while( g_ascii_isdigit( *fmt ) )
                                        len = len * 10 + ( *(fmt++) - '0' );
                        }
                        else if( g_strncasecmp( fmt, "nick", 4 ) == 0 )
                        {
                                part = bu->nick ? : bu->handle;
                                fmt += 4;
                                ok |= TRUE;
                                break;
                        }
                        else if( g_strncasecmp( fmt, "handle", 6 ) == 0 )
                        {
                                part = bu->handle;
                                fmt += 6;
                                ok |= TRUE;
                                break;
                        }
                        else if( g_strncasecmp( fmt, "full_name", 9 ) == 0 )
                        {
                                part = bu->fullname;
                                fmt += 9;
                                ok |= part && *part;
                                break;
                        }
                        else if( g_strncasecmp( fmt, "first_name", 10 ) == 0 )
                        {
                                part = bu->fullname;
                                fmt += 10;
                                ok |= part && *part;
                                chop = ' ';
                                break;
                        }
                        else if( g_strncasecmp( fmt, "group", 5 ) == 0 )
                        {
                                part = bu->group ? bu->group->name : NULL;
                                fmt += 5;
                                break;
                        }
                        else if( g_strncasecmp( fmt, "account", 7 ) == 0 )
                        {
                                part = bu->ic->acc->tag;
                                fmt += 7;
                                break;
                        }
                        else
                        {
                                g_string_free( ret, TRUE );
                                return NULL;
                        }
                }
                
                if( !part )
                        continue;
                
                /* Credits to Josay_ in #bitlbee for this idea. //TRANSLIT
                   should do lossy/approximate conversions, so letters with
                   accents don't just get stripped. Note that it depends on
                   LC_CTYPE being set to something other than C/POSIX. */
                if( !( irc && irc->status & IRC_UTF8_NICKS ) )
                        part = asc = g_convert_with_fallback( part, -1, "ASCII//TRANSLIT",
                                                              "UTF-8", "", NULL, NULL, NULL );
                
                if( part && chop && ( s = strchr( part, chop ) ) )
                        len = MIN( len, s - part );
                
                if( part )
                {
                        if( len < INT_MAX )
                                g_string_append_len( ret, part, len );
                        else
                                g_string_append( ret, part );
                }
                g_free( asc );
        }
        
        rets = g_string_free( ret, FALSE );
        if( ok && rets && *rets )
        {
                nick_strip( irc, rets );
                rets[MAX_NICK_LENGTH] = '\0';
                return rets;
        }
        g_free( rets );
        return NULL;
}

void nick_dedupe( bee_user_t *bu, char nick[MAX_NICK_LENGTH+1] )
{
        irc_t *irc = (irc_t*) bu->bee->ui_data;
        int inf_protection = 256;
        irc_user_t *iu;
        
        /* Now, find out if the nick is already in use at the moment, and make
           subtle changes to make it unique. */
        while( !nick_ok( irc, nick ) ||
               ( ( iu = irc_user_by_name( irc, nick ) ) && iu->bu != bu ) )
        {
                if( strlen( nick ) < ( MAX_NICK_LENGTH - 1 ) )
                {
                        nick[strlen(nick)+1] = 0;
                        nick[strlen(nick)] = '_';
                }
                else
                {
                        nick[0] ++;
                }
                
                if( inf_protection-- == 0 )
                {
                        g_snprintf( nick, MAX_NICK_LENGTH + 1, "xx%x", rand() );
                        
                        irc_rootmsg( irc, "Warning: Something went wrong while trying "
                                          "to generate a nickname for contact %s on %s.",
                                          bu->handle, bu->ic->acc->tag );
                        irc_rootmsg( irc, "This might be a bug in BitlBee, or the result "
                                          "of a faulty nick_format setting. Will use %s "
                                          "instead.", nick );
                        
                        break;
                }
        }
}

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

void nick_del( bee_user_t *bu )
{
        g_hash_table_remove( bu->ic->acc->nicks, bu->handle );
}


void nick_strip( irc_t *irc, char *nick )
{
        int len = 0;
        
        if( irc && ( irc->status & IRC_UTF8_NICKS ) )
        {
                gunichar c;
                char *p = nick, *n, tmp[strlen(nick)+1];
                
                while( p && *p )
                {
                        c = g_utf8_get_char_validated( p, -1 );
                        n = g_utf8_find_next_char( p, NULL );
                        
                        if( ( c < 0x7f && !( strchr( nick_lc_chars, c ) ||
                                             strchr( nick_uc_chars, c ) ) ) ||
                            !g_unichar_isgraph( c ) )
                        {
                                strcpy( tmp, n );
                                strcpy( p, tmp );
                        }
                        else
                                p = n;
                }
                if( p )
                        len = p - nick;
        }
        else
        {
                int i;
                
                for( i = len = 0; nick[i] && len < MAX_NICK_LENGTH; i++ )
                {
                        if( strchr( nick_lc_chars, nick[i] ) || 
                            strchr( nick_uc_chars, nick[i] ) )
                        {
                                nick[len] = nick[i];
                                len++;
                        }
                }
        }
        if( g_ascii_isdigit( nick[0] ) )
        {
                char *orig;
                
                /* First character of a nick can't be a digit, so insert an
                   underscore if necessary. */
                orig = g_strdup( nick );
                g_snprintf( nick, MAX_NICK_LENGTH, "_%s", orig );
                g_free( orig );
                len ++;
        }
        while( len <= MAX_NICK_LENGTH )
                nick[len++] = '\0';
}

gboolean nick_ok( irc_t *irc, const char *nick )
{
        const char *s;
        
        /* Empty/long nicks are not allowed, nor numbers at [0] */
        if( !*nick || g_ascii_isdigit( nick[0] ) || strlen( nick ) > MAX_NICK_LENGTH )
                return 0;
        
        if( irc && ( irc->status & IRC_UTF8_NICKS ) )
        {
                gunichar c;
                const char *p = nick, *n;
                
                while( p && *p )
                {
                        c = g_utf8_get_char_validated( p, -1 );
                        n = g_utf8_find_next_char( p, NULL );
                        
                        if( ( c < 0x7f && !( strchr( nick_lc_chars, c ) ||
                                             strchr( nick_uc_chars, c ) ) ) ||
                            !g_unichar_isgraph( c ) )
                        {
                                return FALSE;
                        }
                        p = n;
                }
        }
        else
        {
                for( s = nick; *s; s ++ )
                        if( !strchr( nick_lc_chars, *s ) && !strchr( nick_uc_chars, *s ) )
                                return FALSE;
        }
        
        return TRUE;
}

int nick_lc( irc_t *irc, 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];
                }
        
        if( irc && ( irc->status & IRC_UTF8_NICKS ) )
        {
                gchar *down = g_utf8_strdown( nick, -1 );
                if( strlen( down ) > strlen( nick ) )
                {
                        /* Well crap. Corrupt it if we have to. */
                        down[strlen(nick)] = '\0';
                }
                strcpy( nick, down );
                g_free( down );
        }
        
        for( i = 0; nick[i]; i ++ )
                if( ((guchar)nick[i]) < 0x7f )
                        nick[i] = tab[(guchar)nick[i]];
        
        return nick_ok( irc, nick );
}

int nick_cmp( irc_t *irc, 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( irc, aa ) && nick_lc( irc, bb ) )
        {
                return( strcmp( aa, bb ) );
        }
        else
        {
                return( -1 );   /* Hmm... Not a clear answer.. :-/ */
        }
}