/*
 * Copyright (c) 2016, 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.
 *
 * 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.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package jdk.tools.jaotc.jnilibelf;

import java.nio.ByteOrder;

import jdk.tools.jaotc.jnilibelf.JNILibELFAPI.ELF;

Class that abstracts ELF target details.
/**
 * Class that abstracts ELF target details.
 *
 */
public class JNIELFTargetInfo {
    
ELF Class of the target.
/**
     * ELF Class of the target.
     */
    private static final int elfClass;
    
Target architecture.
/**
     * Target architecture.
     */
    private static final int arch;
    
Architecture endian-ness.
/**
     * Architecture endian-ness.
     */
    private static final int endian;

    
Target OS string.
/**
     * Target OS string.
     */
    private static final String osName;

    static {
        // Find the target arch details
        String archStr = System.getProperty("os.arch").toLowerCase();
        String datamodelStr = System.getProperty("sun.arch.data.model");

        if (datamodelStr.equals("32")) {
            elfClass = ELF.ELFCLASS32;
        } else if (datamodelStr.equals("64")) {
            elfClass = ELF.ELFCLASS64;
        } else {
            System.out.println("Failed to discover ELF class!");
            elfClass = ELF.ELFCLASSNONE;
        }

        ByteOrder bo = ByteOrder.nativeOrder();
        if (bo == ByteOrder.LITTLE_ENDIAN) {
            endian = ELF.ELFDATA2LSB;
        } else if (bo == ByteOrder.BIG_ENDIAN) {
            endian = ELF.ELFDATA2MSB;
        } else {
            System.out.println("Failed to discover endian-ness!");
            endian = ELF.ELFDATANONE;
        }

        if (archStr.equals("x86")) {
            arch = ELF.EM_386;
        } else if (archStr.equals("amd64") || archStr.equals("x86_64")) {
            arch = ELF.EM_X64_64;
        } else if (archStr.equals("sparcv9")) {
            arch = ELF.EM_SPARCV9;
        } else {
            System.out.println("Unsupported architecture " + archStr);
            arch = ELF.EM_NONE;
        }

        osName = System.getProperty("os.name").toLowerCase();
    }

    public static int getELFArch() {
        return arch;
    }

    public static int getELFClass() {
        return elfClass;
    }

    public static int getELFEndian() {
        return endian;
    }

    public static String getOsName() {
        return osName;
    }

    public static int createReloca() {
        switch (arch) {
            case ELF.EM_X64_64:
                return 1;
            default:
                return 0;
        }
    }

    public static int sizeOfSymtabEntry() {
        return JNILibELFAPI.size_of_Sym(elfClass);
    }

    public static int sizeOfRelocEntry() {
        if (createReloca() == 1) {
            return JNILibELFAPI.size_of_Rela(elfClass);
        } else {
            return JNILibELFAPI.size_of_Rel(elfClass);
        }
    }
}