source: vis_dev/glu-2.3/src/sparse/sparse_int.h @ 26

#include "sparse.h"
#include "util.h"


/*
 *  sorted, double-linked list insertion
 *
 *  type: object type
 *
 *  first, last: fields (in header) to head and tail of the list
 *  count: field (in header) of length of the list
 *
 *  next, prev: fields (in object) to link next and previous objects
 *  value: field (in object) which controls the order
 *
 *  newval: value field for new object
 *  e: an object to use if insertion needed (set to actual value used)
 */

#define sorted_insert(type, first, last, count, next, prev, value, newval, e) \
    if (last == 0) { \
        e->value = newval; \
        first = e; \
        last = e; \
        e->next = 0; \
        e->prev = 0; \
        count++; \
    } else if (last->value < newval) { \
        e->value = newval; \
        last->next = e; \
        e->prev = last; \
        last = e; \
        e->next = 0; \
        count++; \
    } else if (first->value > newval) { \
        e->value = newval; \
        first->prev = e; \
        e->next = first; \
        first = e; \
        e->prev = 0; \
        count++; \
    } else { \
        type *p; \
        for(p = first; p->value < newval; p = p->next) \
            ; \
        if (p->value > newval) { \
            e->value = newval; \
            p = p->prev; \
            p->next->prev = e; \
            e->next = p->next; \
            p->next = e; \
            e->prev = p; \
            count++; \
        } else { \
            e = p; \
        } \
    }


/*
 *  double linked-list deletion
 */
#define dll_unlink(p, first, last, next, prev, count) { \
    if (p->prev == 0) { \
        first = p->next; \
    } else { \
        p->prev->next = p->next; \
    } \
    if (p->next == 0) { \
        last = p->prev; \
    } else { \
        p->next->prev = p->prev; \
    } \
    count--; \
}


#ifdef FAST_AND_LOOSE
extern sm_element *sm_element_freelist;
extern sm_row *sm_row_freelist;
extern sm_col *sm_col_freelist;

#define sm_element_alloc(newobj) \
    if (sm_element_freelist == NIL(sm_element)) { \
        newobj = ALLOC(sm_element, 1); \
    } else { \
        newobj = sm_element_freelist; \
        sm_element_freelist = sm_element_freelist->next_col; \
    } \
    newobj->user_word = NIL(char); \

#define sm_element_free(e) \
    (e->next_col = sm_element_freelist, sm_element_freelist = e)

#else

#define sm_element_alloc(newobj)        \
    newobj = ALLOC(sm_element, 1);      \
    newobj->user_word = NIL(char);
#define sm_element_free(e)              \
    FREE(e)
#endif


EXTERN void sm_row_remove_element(sm_row *, sm_element *);
EXTERN void sm_col_remove_element(sm_col *, sm_element *);

/* LINTLIBRARY */