harvey/sys/src/cmd/gs/src/zarray.c

/* Copyright (C) 1989, 1992, 1993, 1999 Aladdin Enterprises.  All rights reserved.
  
  This software is provided AS-IS with no warranty, either express or
  implied.
  
  This software is distributed under license and may not be copied,
  modified or distributed except as expressly authorized under the terms
  of the license contained in the file LICENSE in this distribution.
  
  For more information about licensing, please refer to
  http://www.ghostscript.com/licensing/. For information on
  commercial licensing, go to http://www.artifex.com/licensing/ or
  contact Artifex Software, Inc., 101 Lucas Valley Road #110,
  San Rafael, CA  94903, U.S.A., +1(415)492-9861.
*/

/* $Id: zarray.c,v 1.5 2004/08/04 19:36:13 stefan Exp $ */
/* Array operators */
#include "memory_.h"
#include "ghost.h"
#include "ialloc.h"
#include "ipacked.h"
#include "oper.h"
#include "store.h"

/* The generic operators (copy, get, put, getinterval, putinterval, */
/* length, and forall) are implemented in zgeneric.c. */

/* <int> array <array> */
int
zarray(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    uint size;
    int code;

    check_int_leu(*op, max_array_size);
    size = op->value.intval;
    code = ialloc_ref_array((ref *)op, a_all, size, "array");
    if (code < 0)
	return code;
    refset_null(op->value.refs, size);
    return 0;
}

/* <array> aload <obj_0> ... <obj_n-1> <array> */
private int
zaload(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    ref aref;
    uint asize;

    ref_assign(&aref, op);
    if (!r_is_array(&aref))
	return_op_typecheck(op);
    check_read(aref);
    asize = r_size(&aref);
    if (asize > ostop - op) {	/* Use the slow, general algorithm. */
	int code = ref_stack_push(&o_stack, asize);
	uint i;
	const ref_packed *packed = aref.value.packed;

	if (code < 0)
	    return code;
	for (i = asize; i > 0; i--, packed = packed_next(packed))
	    packed_get(imemory, packed, ref_stack_index(&o_stack, i));
	*osp = aref;
	return 0;
    }
    if (r_has_type(&aref, t_array))
	memcpy(op, aref.value.refs, asize * sizeof(ref));
    else {
	uint i;
	const ref_packed *packed = aref.value.packed;
	os_ptr pdest = op;

	for (i = 0; i < asize; i++, pdest++, packed = packed_next(packed))
	    packed_get(imemory, packed, pdest);
    }
    push(asize);
    ref_assign(op, &aref);
    return 0;
}

/* <obj_0> ... <obj_n-1> <array> astore <array> */
private int
zastore(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    uint size;
    int code;

    check_write_type(*op, t_array);
    size = r_size(op);
    if (size > op - osbot) {
	/* The store operation might involve other stack segments. */
	ref arr;

	if (size >= ref_stack_count(&o_stack))
	    return_error(e_stackunderflow);
	arr = *op;
	code = ref_stack_store(&o_stack, &arr, size, 1, 0, true, idmemory,
			       "astore");
	if (code < 0)
	    return code;
	ref_stack_pop(&o_stack, size);
	*ref_stack_index(&o_stack, 0) = arr;
    } else {
	code = refcpy_to_old(op, 0, op - size, size, idmemory, "astore");
	if (code < 0)
	    return code;
	op[-(int)size] = *op;
	pop(size);
    }
    return 0;
}

/* ------ Initialization procedure ------ */

const op_def zarray_op_defs[] =
{
    {"1aload", zaload},
    {"1array", zarray},
    {"1astore", zastore},
    op_def_end(0)
};