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list.h

/*
GOCR Copyright (C) 2000  Joerg Schulenburg Joerg.Schulenburg@physik.uni-magdeburg.de 
GOCR API Copyright (C) 2001 Bruno Barberi Gnecco <brunobg@sourceforge.net>

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
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#ifndef GOCR_LIST_H
#define GOCR_LIST_H

/*
 * Structures
 */
 
struct element {
   struct element *next, *previous;
   void *data;
};
typedef struct element Element;

struct list {
   Element *header;
   Element *tail;
   Element **fix;               /* fixes the list_del header problem */
   Element **current;           /* for(each_element) */
   int n;                       /* number of elements */
   int level;                   /* level of nested fors */
};
typedef struct list List;

/*
 * Functions
 */

void    list_init               ( List *l );
int     list_app                ( List *l, void *data );
int     list_ins                ( List *l, void *data_after, void *data);
Element*list_element_from_data  ( List *l, void *data );
int     list_del                ( List *l, void *data );
void    list_free               ( List *l );
int     list_higher_level       ( List *l );
void    list_lower_level        ( List *l );
void *  list_next               ( List *l, void *data );
void *  list_prev               ( List *l, void *data );
void    list_sort               ( List *l, int (*compare)(const void *, const void *) );

#define list_empty(l)                   ((l)->header == NULL ? 1 : 0)
#define list_get_header(l)              ((l)->header->data)
#define list_get_tail(l)                ((l)->tail->data)
#define list_get_current(l)             ((l)->current[(l)->level]->data)
#define list_get_cur_prev(l)            ((l)->current[(l)->level]->previous == NULL ? \
                        NULL : (l)->current[(l)->level]->previous->data )
#define list_get_cur_next(l)            ((l)->current[(l)->level]->next == NULL ? \
                        NULL : (l)->current[(l)->level]->next->data )
#define list_total(l)                   ((l)->n)

#define for_each_data(l)                \
 if (list_higher_level(l) == 0) { \
   for ( ; (l)->current[(l)->level]; (l)->current[(l)->level] = \
        (l)->current[(l)->level]->next ) { \
     if ( (l)->fix[(l)->level] ) { /* fix level */\
       int i; \
       for ( i = (l)->level - 1; i >= 0; i-- ) {  \
       /* check if some other copy of (l)->fix[(l)->level] exists */ \
        \
         if ( (l)->fix[i] == (l)->fix[(l)->level] ) break; \
       } \
       if ( i < 0 ) { /* no, it doesn't. Free it */ \
         free((l)->fix[(l)->level]); \
       } \
       (l)->fix[(l)->level] = NULL; \
     }

#define end_for_each(l)                 \
   } \
 list_lower_level(l); \
 }

#endif

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