/*
 * Copyright (c) 2020, 2020, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package com.oracle.svm.core.c.struct;

import org.graalvm.nativeimage.ImageSingletons;
import org.graalvm.nativeimage.c.struct.CStruct;
import org.graalvm.nativeimage.c.struct.RawStructure;
import org.graalvm.word.PointerBase;
import org.graalvm.word.UnsignedWord;
import org.graalvm.word.WordFactory;

Supplies static methods that provide access to the offset of fields of CStruct and RawStructure structures. /**
 * Supplies static methods that provide access to the offset of fields of {@link CStruct} and
 * {@link RawStructure} structures.
 */
public final class OffsetOf {
    public interface Support {
        int offsetOf(Class<? extends PointerBase> clazz, String fieldName);
    }

    private OffsetOf() {
    }

    public static int get(Class<? extends PointerBase> clazz, String fieldName) {
        return ImageSingletons.lookup(Support.class).offsetOf(clazz, fieldName);
    }

    public static UnsignedWord unsigned(Class<? extends PointerBase> clazz, String fieldName) {
        return WordFactory.unsigned(get(clazz, fieldName));
    }
}