/* Copyright (C) 2001-2018 Artifex Software, Inc.
   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.

   Refer to licensing information at http://www.artifex.com or contact
   Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
   CA 94945, U.S.A., +1(415)492-9861, for further information.
*/


/* 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_type(*op, t_integer);
    if (op->value.intval < 0)
        return_error(gs_error_rangecheck);
    if (op->value.intval > max_array_size)
        return_error(gs_error_limitcheck);
    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> */
static 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> */
static int
zastore(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    uint size;
    int code;

    if (!r_is_array(op))
        return_op_typecheck(op);
    size = r_size(op);
    /* Amazingly, the following is valid: 0 array noaccess astore */
    if (size == 0)
        return 0;
    if (!r_has_type_attrs(op, t_array, a_write))
        return_error(gs_error_invalidaccess);
    if (size > op - osbot) {
        /* The store operation might involve other stack segments. */
        ref arr;

        if (size >= ref_stack_count(&o_stack))
            return_error(gs_error_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)
};
