/* Copyright (C) 1997, 1998 Aladdin Enterprises.  All rights reserved.

   This file is part of Aladdin Ghostscript.

   Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
   or distributor accepts any responsibility for the consequences of using it,
   or for whether it serves any particular purpose or works at all, unless he
   or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
   License (the "License") for full details.

   Every copy of Aladdin Ghostscript must include a copy of the License,
   normally in a plain ASCII text file named PUBLIC.  The License grants you
   the right to copy, modify and redistribute Aladdin Ghostscript, but only
   under certain conditions described in the License.  Among other things, the
   License requires that the copyright notice and this notice be preserved on
   all copies.
 */

/*$Id: zmisc3.c $ */
/* Miscellaneous LanguageLevel 3 operators */
#include "ghost.h"
#include "gsclipsr.h"
#include "oper.h"
#include "igstate.h"
#include "store.h"

/* - clipsave - */
private int
zclipsave(os_ptr op)
{
    return gs_clipsave(igs);
}

/* - cliprestore - */
private int
zcliprestore(os_ptr op)
{
    return gs_cliprestore(igs);
}

/* <proc1> <proc2> .eqproc <bool> */
/*
 * Test whether two procedures are equal to depth 10.
 * This is the equality test used by idiom recognition in 'bind'.
 */
#define MAX_DEPTH 10		/* depth is per Adobe specification */
typedef struct ref2_s {
    ref proc1, proc2;
} ref2_t;
private int
zeqproc(register os_ptr op)
{
    ref2_t stack[MAX_DEPTH + 1];
    ref2_t *top = stack;

    make_array(&stack[0].proc1, 0, 1, op - 1);
    make_array(&stack[0].proc2, 0, 1, op);
    for (;;) {
	long i;

	if (r_size(&top->proc1) == 0) {
	    /* Finished these arrays, go up to next level. */
	    if (top == stack) {
		/* We're done matching: it succeeded. */
		make_true(op - 1);
		pop(1);
		return 0;
	    }
	    --top;
	    continue;
	}
	/* Look at the next elements of the arrays. */
	i = r_size(&top->proc1) - 1;
	array_get(&top->proc1, i, &top[1].proc1);
	array_get(&top->proc2, i, &top[1].proc2);
	r_dec_size(&top->proc1, 1);
	++top;
	/*
	 * Amazingly enough, the objects' executable attributes are not
	 * required to match.  This means { x load } will match { /x load },
	 * even though this is clearly wrong.
	 */
#if 0
	if (r_has_attr(&top->proc1, a_executable) !=
	    r_has_attr(&top->proc2, a_executable)
	    )
	    break;
#endif
	if (obj_eq(&top->proc1, &top->proc2)) {
	    /* Names don't match strings. */
	    if (r_type(&top->proc1) != r_type(&top->proc2) &&
		(r_type(&top->proc1) == t_name ||
		 r_type(&top->proc2) == t_name)
		)
		break;
	    --top;		/* no recursion */
	    continue;
	}
	if (r_is_array(&top->proc1) && r_is_array(&top->proc2) &&
	    r_size(&top->proc1) == r_size(&top->proc2) &&
	    top < stack + (MAX_DEPTH - 1)
	    ) {
	    /* Descend into the arrays. */
	    continue;
	}
	break;
    }
    /* An exit from the loop indicates that matching failed. */
    make_false(op - 1);
    pop(1);
    return 0;
}

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

const op_def zmisc3_op_defs[] =
{
    op_def_begin_ll3(),
    {"0cliprestore", zcliprestore},
    {"0clipsave", zclipsave},
    {"2.eqproc", zeqproc},
    op_def_end(0)
};
