ftptest.leeds.ac.uk/2015.02.ftptest.leeds.ac.uk.tar/ftptest.leeds.ac.uk/bionet/CAE-GROUP/SCL-WIN3x/FED_PLUS.EXE/LINKLIST.C

C/C++ Source or Header | 1994-07-25 | 4KB | 235 lines

static char rcsid[] = "$Id: linklist.c,v 1.2 1993/10/15 18:49:55 libes Exp $";

/*
 * This work was supported by the United States Government, and is
 * not subject to copyright.
 *
 * $Log: linklist.c,v $
 * Revision 1.2  1993/10/15  18:49:55  libes
 * CADDETC certified
 *
 * Revision 1.4  1993/01/19  22:17:27  libes
 * *** empty log message ***
 *
 * Revision 1.3  1992/08/18  17:16:22  libes
 * rm'd extraneous error messages
 *
 * Revision 1.2  1992/06/08  18:08:05  libes
 * prettied up interface to print_objects_when_running
 */

#define LINKLIST_C
#include "linklist.h"

void
LISTinitialize(void)
{
    MEMinitialize(&LINK_fl,sizeof(struct Link),500,100);
    MEMinitialize(&LIST_fl,sizeof(struct Linked_List),100,50);

    ERROR_empty_list = ERRORcreate(
"Empty list in %s.", SEVERITY_ERROR);

}

Boolean
LISTempty(Linked_List list)
{
    if (!list) return true;
    return (list->mark->next == list->mark);
}

Linked_List
LISTcreate()
{
    Linked_List list = LIST_new();
    list->mark = LINK_new();
    list->mark->next = list->mark->prev = list->mark;
    return(list);
}

#if 0
/* could optimize this function! */
Linked_List
LISTcreate_with(Generic g)
{
    Linked_List dst = LISTcreate();
    LISTadd(dst,g);
    return(dst);
}
#endif

Linked_List
LISTcopy(Linked_List src)
{
    Linked_List dst = LISTcreate();
    LISTdo(src,x,Generic)
        LISTadd(dst,x);
    LISTod
    return dst;
}


void
LISTfree(list)
Linked_List list;
{
    Link p, q = list->mark->next;

    for (p = q->next; p != list->mark; q = p, p = p->next) {
            LINK_destroy(q);
    }
    if (q != list->mark) LINK_destroy(q);
    LINK_destroy(list->mark);
    LIST_destroy(list);
}

Generic
LISTadd_first(Linked_List list, Generic item)
{
    Link        node;

    node = LINK_new();
    node->data = item;
    (node->next = list->mark->next)->prev = node;
    (list->mark->next = node)->prev = list->mark;
    return item;
}

Generic
LISTadd_last(Linked_List list, Generic item)
{
    Link        node;

    node = LINK_new();
    node->data = item;
    (node->prev = list->mark->prev)->next = node;
    (list->mark->prev = node)->next = list->mark;
    return item;
}

Generic
LISTadd_after(Linked_List list, Link link, Generic item)
{
    Link node;

    if (link == LINK_NULL)
    LISTadd_first(list, item);
    else {
    node = LINK_new();
    node->data = item;
    (node->next = link->next)->prev = node;
    (link->next = node)->prev = link;
    }
    return item;
}

Generic
LISTadd_before(Linked_List list, Link link, Generic item)
{
    Link node;

    if (link == LINK_NULL)
    LISTadd_last(list, item);
    else {
    node = LINK_new();
    node->data = item;

    link->prev->next = node;    /* fix up previous link */
    node->prev = link->prev;
    node->next = link;
    link->prev = node;        /* fix up next link */
    }
    return item;
}


Generic
LISTremove_first(Linked_List list)
{
    Link        node;
    Generic        item;

    node = list->mark->next;
    if (node == list->mark) {
    ERRORreport(ERROR_empty_list, "LISTremove_first");
    return NULL;
    }
    item = node->data;
    (list->mark->next = node->next)->prev = list->mark;
    LINK_destroy(node);
    return item;
}

/* 1st arg is historical and can be removed */
/*ARGSUSED*/
Generic
LISTremove(Linked_List list, Link link)
{
    Generic        item;

    link->next->prev = link->prev;
    link->prev->next = link->next;
    item = link->data;
    LINK_destroy(link);
    return item;
}

Generic
LISTget_first(Linked_List list)
{
    Link node;
    Generic item;

    node = list->mark->next;
    if (node == list->mark) {
    return NULL;
    }
    item = node->data;
    return item;
}
Generic
LISTget_second(Linked_List list)
{
    Link        node;
    Generic        item;

    node = list->mark->next;
    if (node == list->mark) {
    return NULL;
    }
    node = node->next;
    if (node == list->mark) {
    return NULL;
    }
    item = node->data;
    return item;
}

/* first is 1, not 0 */
Generic
LISTget_nth(Linked_List list, int n)
{
    int count = 1;
    Link node;

    for (node = list->mark->next; node != list->mark; node = node->next) {
        if (n == count++) return(node->data);
    }
    return(0);
}

int
LISTget_length(Linked_List list)
{
    Link node;
    int count = 0;

    if (!list) return 0;

    for (node = list->mark->next; node != list->mark; node = node->next) {
        count++;
    }
    return count;
}