cpython/Objects/listobject.c

/* List object implementation */

#include "allobjects.h"

object *
newlistobject(size)
	int size;
{
	int i;
	listobject *op;
	if (size < 0) {
		err_badcall();
		return NULL;
	}
	op = (listobject *) malloc(sizeof(listobject));
	if (op == NULL) {
		return err_nomem();
	}
	if (size <= 0) {
		op->ob_item = NULL;
	}
	else {
		op->ob_item = (object **) malloc(size * sizeof(object *));
		if (op->ob_item == NULL) {
			free((ANY *)op);
			return err_nomem();
		}
	}
	NEWREF(op);
	op->ob_type = &Listtype;
	op->ob_size = size;
	for (i = 0; i < size; i++)
		op->ob_item[i] = NULL;
	return (object *) op;
}

int
getlistsize(op)
	object *op;
{
	if (!is_listobject(op)) {
		err_badcall();
		return -1;
	}
	else
		return ((listobject *)op) -> ob_size;
}

object *
getlistitem(op, i)
	object *op;
	int i;
{
	if (!is_listobject(op)) {
		err_badcall();
		return NULL;
	}
	if (i < 0 || i >= ((listobject *)op) -> ob_size) {
		err_setstr(IndexError, "list index out of range");
		return NULL;
	}
	return ((listobject *)op) -> ob_item[i];
}

int
setlistitem(op, i, newitem)
	register object *op;
	register int i;
	register object *newitem;
{
	register object *olditem;
	if (!is_listobject(op)) {
		if (newitem != NULL)
			DECREF(newitem);
		err_badcall();
		return -1;
	}
	if (i < 0 || i >= ((listobject *)op) -> ob_size) {
		if (newitem != NULL)
			DECREF(newitem);
		err_setstr(IndexError, "list assignment index out of range");
		return -1;
	}
	olditem = ((listobject *)op) -> ob_item[i];
	((listobject *)op) -> ob_item[i] = newitem;
	if (olditem != NULL)
		DECREF(olditem);
	return 0;
}

static int
ins1(self, where, v)
	listobject *self;
	int where;
	object *v;
{
	int i;
	object **items;
	if (v == NULL) {
		err_badcall();
		return -1;
	}
	items = self->ob_item;
	RESIZE(items, object *, self->ob_size+1);
	if (items == NULL) {
		err_nomem();
		return -1;
	}
	if (where < 0)
		where = 0;
	if (where > self->ob_size)
		where = self->ob_size;
	for (i = self->ob_size; --i >= where; )
		items[i+1] = items[i];
	INCREF(v);
	items[where] = v;
	self->ob_item = items;
	self->ob_size++;
	return 0;
}

int
inslistitem(op, where, newitem)
	object *op;
	int where;
	object *newitem;
{
	if (!is_listobject(op)) {
		err_badcall();
		return -1;
	}
	return ins1((listobject *)op, where, newitem);
}

int
addlistitem(op, newitem)
	object *op;
	object *newitem;
{
	if (!is_listobject(op)) {
		err_badcall();
		return -1;
	}
	return ins1((listobject *)op,
		(int) ((listobject *)op)->ob_size, newitem);
}

/* Methods */

static void
list_dealloc(op)
	listobject *op;
{
	int i;
	for (i = 0; i < op->ob_size; i++) {
		if (op->ob_item[i] != NULL)
			DECREF(op->ob_item[i]);
	}
	if (op->ob_item != NULL)
		free((ANY *)op->ob_item);
	free((ANY *)op);
}

static void
list_print(op, fp, flags)
	listobject *op;
	FILE *fp;
	int flags;
{
	int i;
	fprintf(fp, "[");
	for (i = 0; i < op->ob_size && !StopPrint; i++) {
		if (i > 0) {
			fprintf(fp, ", ");
		}
		printobject(op->ob_item[i], fp, flags);
	}
	fprintf(fp, "]");
}

object *
list_repr(v)
	listobject *v;
{
	object *s, *t, *comma;
	int i;
	s = newstringobject("[");
	comma = newstringobject(", ");
	for (i = 0; i < v->ob_size && s != NULL; i++) {
		if (i > 0)
			joinstring(&s, comma);
		t = reprobject(v->ob_item[i]);
		joinstring(&s, t);
		DECREF(t);
	}
	DECREF(comma);
	t = newstringobject("]");
	joinstring(&s, t);
	DECREF(t);
	return s;
}

static int
list_compare(v, w)
	listobject *v, *w;
{
	int len = (v->ob_size < w->ob_size) ? v->ob_size : w->ob_size;
	int i;
	for (i = 0; i < len; i++) {
		int cmp = cmpobject(v->ob_item[i], w->ob_item[i]);
		if (cmp != 0)
			return cmp;
	}
	return v->ob_size - w->ob_size;
}

static int
list_length(a)
	listobject *a;
{
	return a->ob_size;
}

static object *
list_item(a, i)
	listobject *a;
	int i;
{
	if (i < 0 || i >= a->ob_size) {
		err_setstr(IndexError, "list index out of range");
		return NULL;
	}
	INCREF(a->ob_item[i]);
	return a->ob_item[i];
}

static object *
list_slice(a, ilow, ihigh)
	listobject *a;
	int ilow, ihigh;
{
	listobject *np;
	int i;
	if (ilow < 0)
		ilow = 0;
	else if (ilow > a->ob_size)
		ilow = a->ob_size;
	if (ihigh < 0)
		ihigh = 0;
	if (ihigh < ilow)
		ihigh = ilow;
	else if (ihigh > a->ob_size)
		ihigh = a->ob_size;
	np = (listobject *) newlistobject(ihigh - ilow);
	if (np == NULL)
		return NULL;
	for (i = ilow; i < ihigh; i++) {
		object *v = a->ob_item[i];
		INCREF(v);
		np->ob_item[i - ilow] = v;
	}
	return (object *)np;
}

static object *
list_concat(a, bb)
	listobject *a;
	object *bb;
{
	int size;
	int i;
	listobject *np;
	if (!is_listobject(bb)) {
		err_badarg();
		return NULL;
	}
#define b ((listobject *)bb)
	size = a->ob_size + b->ob_size;
	np = (listobject *) newlistobject(size);
	if (np == NULL) {
		return err_nomem();
	}
	for (i = 0; i < a->ob_size; i++) {
		object *v = a->ob_item[i];
		INCREF(v);
		np->ob_item[i] = v;
	}
	for (i = 0; i < b->ob_size; i++) {
		object *v = b->ob_item[i];
		INCREF(v);
		np->ob_item[i + a->ob_size] = v;
	}
	return (object *)np;
#undef b
}

static int
list_ass_item(a, i, v)
	listobject *a;
	int i;
	object *v;
{
	if (i < 0 || i >= a->ob_size) {
		err_setstr(IndexError, "list assignment index out of range");
		return -1;
	}
	if (v == NULL)
		return list_ass_slice(a, i, i+1, v);
	INCREF(v);
	DECREF(a->ob_item[i]);
	a->ob_item[i] = v;
	return 0;
}

static int
list_ass_slice(a, ilow, ihigh, v)
	listobject *a;
	int ilow, ihigh;
	object *v;
{
	object **item;
	int n; /* Size of replacement list */
	int d; /* Change in size */
	int k; /* Loop index */
#define b ((listobject *)v)
	if (v == NULL)
		n = 0;
	else if (is_listobject(v))
		n = b->ob_size;
	else {
		err_badarg();
		return -1;
	}
	if (ilow < 0)
		ilow = 0;
	else if (ilow > a->ob_size)
		ilow = a->ob_size;
	if (ihigh < 0)
		ihigh = 0;
	if (ihigh < ilow)
		ihigh = ilow;
	else if (ihigh > a->ob_size)
		ihigh = a->ob_size;
	item = a->ob_item;
	d = n - (ihigh-ilow);
	if (d <= 0) { /* Delete -d items; DECREF ihigh-ilow items */
		for (k = ilow; k < ihigh; k++)
			DECREF(item[k]);
		if (d < 0) {
			for (/*k = ihigh*/; k < a->ob_size; k++)
				item[k+d] = item[k];
			a->ob_size += d;
			RESIZE(item, object *, a->ob_size); /* Can't fail */
			a->ob_item = item;
		}
	}
	else { /* Insert d items; DECREF ihigh-ilow items */
		RESIZE(item, object *, a->ob_size + d);
		if (item == NULL) {
			err_nomem();
			return -1;
		}
		for (k = a->ob_size; --k >= ihigh; )
			item[k+d] = item[k];
		for (/*k = ihigh-1*/; k >= ilow; --k)
			DECREF(item[k]);
		a->ob_item = item;
		a->ob_size += d;
	}
	for (k = 0; k < n; k++, ilow++) {
		object *w = b->ob_item[k];
		INCREF(w);
		item[ilow] = w;
	}
	return 0;
#undef b
}

static object *
ins(self, where, v)
	listobject *self;
	int where;
	object *v;
{
	if (ins1(self, where, v) != 0)
		return NULL;
	INCREF(None);
	return None;
}

static object *
listinsert(self, args)
	listobject *self;
	object *args;
{
	int i;
	if (args == NULL || !is_tupleobject(args) || gettuplesize(args) != 2) {
		err_badarg();
		return NULL;
	}
	if (!getintarg(gettupleitem(args, 0), &i))
		return NULL;
	return ins(self, i, gettupleitem(args, 1));
}

static object *
listappend(self, args)
	listobject *self;
	object *args;
{
	return ins(self, (int) self->ob_size, args);
}

static int
cmp(v, w)
	char *v, *w;
{
	return cmpobject(* (object **) v, * (object **) w);
}

static object *
listsort(self, args)
	listobject *self;
	object *args;
{
	if (args != NULL) {
		err_badarg();
		return NULL;
	}
	err_clear();
	if (self->ob_size > 1)
		qsort((char *)self->ob_item,
				(int) self->ob_size, sizeof(object *), cmp);
	if (err_occurred())
		return NULL;
	INCREF(None);
	return None;
}

int
sortlist(v)
	object *v;
{
	if (v == NULL || !is_listobject(v)) {
		err_badcall();
		return -1;
	}
	v = listsort((listobject *)v, (object *)NULL);
	if (v == NULL)
		return -1;
	DECREF(v);
	return 0;
}

static struct methodlist list_methods[] = {
	{"append",	listappend},
	{"insert",	listinsert},
	{"sort",	listsort},
	{NULL,		NULL}		/* sentinel */
};

static object *
list_getattr(f, name)
	listobject *f;
	char *name;
{
	return findmethod(list_methods, (object *)f, name);
}

static sequence_methods list_as_sequence = {
	list_length,	/*sq_length*/
	list_concat,	/*sq_concat*/
	0,		/*sq_repeat*/
	list_item,	/*sq_item*/
	list_slice,	/*sq_slice*/
	list_ass_item,	/*sq_ass_item*/
	list_ass_slice,	/*sq_ass_slice*/
};

typeobject Listtype = {
	OB_HEAD_INIT(&Typetype)
	0,
	"list",
	sizeof(listobject),
	0,
	list_dealloc,	/*tp_dealloc*/
	list_print,	/*tp_print*/
	list_getattr,	/*tp_getattr*/
	0,		/*tp_setattr*/
	list_compare,	/*tp_compare*/
	list_repr,	/*tp_repr*/
	0,		/*tp_as_number*/
	&list_as_sequence,	/*tp_as_sequence*/
	0,		/*tp_as_mapping*/
};