list.cpp

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#include <../../nrnconf.h>
/* /local/src/master/nrn/src/modlunit/list.c,v 1.3 1997/11/24 16:19:10 hines Exp */
 
/* The following routines support the concept of a list.
That is, one can insert at the head of a list or append to the tail of a
list with linsert<type>() and lappend<type>().
 
In addition, one can insert an item before a known item and it will be
placed in the proper list.
 
Items point to strings, symbols, etc. Note that more than one item in the
same or several lists can point to the same string, symbol.
 
Finally, knowing an item, one can determine the preceding and following
items with next() and prev().
 
Deletion, replacement and moving blocks of items is also supported.
*/
/* For model, makelist and append have been added */
/* Implementation
  The list is a doubly linked list. A special item with element 0 is
  always at the tail of the list and is denoted as the List pointer itself.
  list->next point to the first item in the list and
  list->prev points to the last item in the list.
    i.e. the list is circular
  Note that in an empty list next and prev points to itself.
 
It is intended that this implementation be hidden from the user via the
following function calls.
*/
 
#include <stdlib.h>
#include <cstring>
#include "model.h"
#include "parse1.hpp"
 
#define DEBUG 0
#if DEBUG
static int debugtoken = 1;
#else
static int debugtoken = 0;
#endif
 
static Item* newitem() {
    return (Item*) emalloc(sizeof(Item));
}
 
List* newlist() {
    Item* i;
    i = newitem();
    i->prev = i;
    i->next = i;
    i->element = (void*) 0;
    i->itemtype = 0;
    return (List*) i;
}
 
void freelist(List** plist) /*free the list but not the elements*/
{
    Item *i1, *i2;
    if (!(*plist)) {
        return;
    }
    for (i1 = (*plist)->next; i1 != *plist; i1 = i2) {
        i2 = i1->next;
        free(i1);
    }
    free(*plist);
    *plist = (List*) 0;
}
 
static Item* linkitem(Item* item) {
    Item* i;
 
    i = newitem();
    i->prev = item->prev;
    i->next = item;
    item->prev = i;
    i->prev->next = i;
    return i;
}
 
Item* car(List* list) {
    Item* q = (Item*) list;
    assert(q && q->itemtype == 0);
    return next(q);
}
 
Item* next(Item* item) {
    assert(item->next->itemtype); /* never return the list item */
    return item->next;
}
 
Item* prev(Item* item) {
    assert(item->prev->itemtype); /* never return the list item */
    return item->prev;
}
 
Item* insertstr(Item* item, const char* str) /* insert a copy of the string before item */
/* a copy is made because strings are often assembled into a reusable buffer*/
{
    Item* i;
 
    i = linkitem(item);
    i->element = (void*) stralloc(str, (char*) 0);
    i->itemtype = STRING;
    return i;
}
 
Item* insertitem(Item* item, Item* itm) /* insert a item pointer before item */
{
    Item* i;
 
    i = linkitem(item);
    i->element = (void*) itm;
    i->itemtype = ITEM;
    return i;
}
 
Item* insertsym(Item* item, Symbol* sym) /* insert a symbol before item */
/* a copy is not made because we need the same symbol in different lists */
{
    Item* i;
 
    i = linkitem(item);
    i->element = (void*) sym;
    i->itemtype = SYMBOL;
    return i;
}
 
Item* linsertstr(List* list, const char* str) {
    return insertstr(list->next, str);
}
 
Item* lappendstr(List* list, const char* str) {
    return insertstr(list, str);
}
 
Item* linsertsym(List* list, Symbol* sym) {
    return insertsym(list->next, sym);
}
 
Item* lappendsym(List* list, Symbol* sym) {
    return insertsym(list, sym);
}
 
Item* lappenditem(List* list, Item* item) {
    return insertitem(list, item);
}
 
void remove(Item* item) {
    assert(item->itemtype); /* can't delete list */
    item->next->prev = item->prev;
    item->prev->next = item->next;
    free(item);
}
 
static long mallocsize = 0;
static long mallocpieces = 0;
 
char* emalloc(unsigned n) { /* check return from malloc */
    char* p;
 
    p = static_cast<char*>(malloc(n));
    if (p == (char*) 0) {
        memory_usage();
        diag("out of memory", (char*) 0);
    }
    mallocsize += n;
    mallocpieces++;
    return p;
}
 
void memory_usage() {
    Fprintf(stderr, "malloc'ed a total of %ld bytes in %ld pieces\n", mallocsize, mallocpieces);
}
 
char* stralloc(const char* buf, char* rel) {
    /* allocate space, copy buf, and free rel */
    char* s;
    s = (char*) emalloc((unsigned) (strlen(buf) + 1));
    Strcpy(s, buf);
    if (rel) {
        free(rel);
    }
    return s;
}
 
void deltokens(Item* q1, Item* q2) /* delete tokens from q1 to q2 */
{
    /* It is a serious error if q2 precedes q1 */
    Item* q;
    for (q = q1; q != q2;) {
        q = q->next;
        remove(q->prev);
    }
    remove(q2);
}
 
void move(Item* q1, Item* q2, Item* q3) /* move q1 to q2 and insert before q3*/
{
    /* it is a serious error if q2 precedes q1 */
    assert(q1 && q2);
    assert(q1->itemtype && q2->itemtype);
    q1->prev->next = q2->next; /* remove from first list */
    q2->next->prev = q1->prev;
 
    q1->prev = q3->prev;
    q3->prev->next = q1;
    q3->prev = q2;
    q2->next = q3;
}
 
void movelist(Item* q1, Item* q2, List* s) /* move q1 to q2 from old list to end of list s*/
{
    move(q1, q2, s);
}
 
void replacstr(Item* q, const char* s) {
    q->itemtype = STRING;
    q->element = (void*) stralloc(s, (char*) 0);
}
 
Item* putintoken(const char* s, short type, short toktype) { /* make sure a symbol exists for s and
                                                       append to intoken list */
    Symbol* sym;
    Item* q;
    static int linenum = 0;
 
    if (debugtoken) {
        Fprintf(stderr, "%s|", s);
    }
    if (s == (char*) 0)
        diag("internal error", " in putintoken");
    switch (type) {
    case STRING:
    case REAL:
    case INTEGER:
        q = insertstr(intoken, s);
        q->itemsubtype = toktype;
        return q;
    case NEWLINE:
        q = insertsym(intoken, SYM0);
        q->itemtype = NEWLINE;
        q->itemsubtype = ++linenum;
        return q;
    default:
        if ((sym = lookup(s)) == SYM0) {
            sym = install(s, type);
        }
        break;
    }
    q = insertsym(intoken, sym);
    if (toktype) {
        q->itemsubtype = toktype;
    } else {
        q->itemsubtype = sym->type;
    }
    return q;
}
 
#include <stdarg.h>
 
/* make a list of item pointers: notice that the items themselves remain
in whatever list they happen to be in. */
/* usage is q = makelist(n, q1, q2,..., qn); and q is of type LIST and
   is not in any list */
 
Item* makelist(int narg, ...) {
    va_list ap;
    int i;
    List* l;
    Item *ql, *q;
 
    l = newlist();
    ql = newitem();
    ql->itemtype = LIST;
    ql->element = (void*) l;
    va_start(ap, narg);
    for (i = 0; i < narg; i++) {
        q = va_arg(ap, Item*);
        append(ql, q);
    }
    va_end(ap);
 
    return ql;
}
 
void append(Item* ql, Item* q) {
    assert(ql->itemtype == LIST);
    IGNORE(insertitem((Item*) (LST(ql)), q));
}
 
Item* prepend(Item* ql, Item* q) {
    List* l;
 
    assert(ql->itemtype == LIST);
    l = LST(ql);
    IGNORE(insertitem((Item*) l->next, q));
    return ql;
}
 
/* An item which is an array of item pointers. Note where the size of
the array is held. */
 
Item* itemarray(int narg, ...) {
    va_list ap;
    int i;
    Item *ql, *q, **qa;
 
    ql = newitem();
    va_start(ap, narg);
    ql->itemtype = ITEMARRAY;
    qa = (Item**) emalloc((unsigned) (narg + 1) * sizeof(Item*));
    qa++;
    ql->element = (void*) qa;
    for (i = 0; i < narg; i++) {
        q = va_arg(ap, Item*);
        qa[i] = q;
    }
    va_end(ap);
    ITMA(ql)[-1] = (Item*) ((size_t) narg);
    return ql;
}