/* Copyright (C) 1989, 1992, 1993 Aladdin Enterprises.  All rights reserved.
  
  This file is part of GNU Ghostscript.
  
  GNU Ghostscript is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility to
  anyone for the consequences of using it or for whether it serves any
  particular purpose or works at all, unless he says so in writing.  Refer
  to the GNU Ghostscript General Public License for full details.
  
*/

/* zarray.c */
/* Array operators */
#include "memory_.h"
#include "ghost.h"
#include "errors.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(register os_ptr op)
{	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(register os_ptr op)
{	ref aref;
	ref_assign(&aref, op);
	if ( !r_is_array(&aref) )
	  return_op_typecheck(op);
	check_read(aref);
#define 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(packed, ref_stack_index(&o_stack, i));
		*osp = aref;
		return 0;
	}
	if ( r_has_type(&aref, t_array) )
		memcpy((char *)op, (const char *)aref.value.refs,
		       asize * sizeof(ref));
	else
	   {	register ushort i;
		const ref_packed *packed = aref.value.packed;
		os_ptr pdest = op;
		for ( i = 0; i < asize; i++, pdest++ )
			packed_get(packed, pdest),
			packed = packed_next(packed);
	   }
	push(asize);
#undef asize
	ref_assign(op, &aref);
	return 0;
}

/* <obj_0> ... <obj_n-1> <array> astore <array> */
private int
zastore(register os_ptr op)
{	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,
				       "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, "astore");
		if ( code < 0 )
		  return code;
		op[-(int)size] = *op;
		pop(size);
	  }
	return 0;
}

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

BEGIN_OP_DEFS(zarray_op_defs) {
	{"1aload", zaload},
	{"1array", zarray},
	{"1astore", zastore},
END_OP_DEFS(0) }
