sll.c

Go to the documentation of this file.

/*
 * A utility file. A single linked list.
 *
 * Started date   : 10-11-91
 * Written by     : C. Gaspar
 * UNIX adjustment: G.C. Ballintijn
 *
 */

#define DIMLIB
#include <dim.h>


void sll_init( SLL* head )
{
        head->next = (SLL *)0;
}


int sll_insert_queue( SLL* head, SLL* item )
{
        SLL *auxp;

        DISABLE_AST
        auxp = head;
        while( auxp->next )
                auxp = auxp->next;
        auxp->next = item;
        item->next = 0;
        ENABLE_AST
        return(1);
}


SLL *sll_search( SLL* head, char *data, int size )
{
        DISABLE_AST
        while( (head = head->next) )
        {
                if( !memcmp(head->user_info, data, (size_t)size) )
                {
                        break;
                }
        }
        ENABLE_AST
        return(head);
}


SLL *sll_get_next(SLL* item)
{
        DISABLE_AST
        if( item )
                item = item->next;
        ENABLE_AST
        return(item);
}


int sll_empty( SLL* head )
{
        register int ret;
 
        DISABLE_AST
        if(head->next)
                ret = 0;
        else
                ret = 1;
        ENABLE_AST
        return(ret);
}


int sll_remove( SLL* head, SLL* item )
{
        register int ret = 0;

        DISABLE_AST
        while( head->next )
        {
                if( head->next == item )
                {
                        head->next = item->next;
                        ret = 1;
                        break;
                }
                head = head->next;
        }
        ENABLE_AST
        return(ret);
}       


SLL *sll_remove_head( SLL* head ) 
{
        register SLL *auxp;

        DISABLE_AST
        if( (auxp = head->next) )
        {
                head->next = auxp->next;
        }
        ENABLE_AST
        return(auxp);
}

SLL *sll_get_head( SLL* head ) 
{
        register SLL *auxp;

        DISABLE_AST
        auxp = head->next;
        ENABLE_AST
        return(auxp);
}


SLL *sll_search_next_remove( SLL* item, int offset, char *data, int size )
{
        register SLL *auxp;
 
        DISABLE_AST
        while( (auxp = item->next) )
        {
                if( !memcmp(&(auxp->user_info[offset]), data, (size_t)size) )
                {
                        item->next = auxp->next;
                        break;
                }
                item = auxp;
        }
        ENABLE_AST
        return(auxp);
}