acmi.l2.clientmod.l2_version_switcher.Util.java Source code

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Here is the source code for acmi.l2.clientmod.l2_version_switcher.Util.java

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/*
 * Copyright (c) 2016 acmi
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package acmi.l2.clientmod.l2_version_switcher;

import org.apache.commons.io.IOUtils;
import org.apache.commons.io.output.NullOutputStream;
import org.tukaani.xz.LZMAInputStream;

import java.io.*;
import java.nio.charset.StandardCharsets;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class Util {
    public static List<FileInfo> getFileInfo(InputStream is) {
        return new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_16)).lines().map(FileInfo::parse)
                .collect(Collectors.toList());
    }

    public static InputStream getUnzipStream(InputStream input) throws IOException {
        return new LZMAInputStream(input);
    }

    public static boolean hashEquals(File file, String hashString) throws IOException {
        try {
            MessageDigest md = MessageDigest.getInstance("sha-1");
            try (FileInputStream hashBytes = new FileInputStream(file)) {
                DigestInputStream dis = new DigestInputStream(hashBytes, md);
                IOUtils.copy(dis, NullOutputStream.NULL_OUTPUT_STREAM);
            }
            byte[] hash = md.digest();
            return Arrays.equals(hash, parseHexBinary(hashString));
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
    }

    public static byte[] parseHexBinary(String s) {
        int len = s.length();

        if (len % 2 != 0) {
            throw new IllegalArgumentException("hexBinary needs to be even-length: " + s);
        }

        byte[] out = new byte[len / 2];

        for (int i = 0; i < len; i += 2) {
            int h = hexToBin(s.charAt(i));
            int l = hexToBin(s.charAt(i + 1));
            if (h == -1 || l == -1) {
                throw new IllegalArgumentException("contains illegal character for hexBinary: " + s);
            }

            out[i / 2] = (byte) (h * 16 + l);
        }

        return out;
    }

    private static int hexToBin(char ch) {
        if ('0' <= ch && ch <= '9') {
            return ch - '0';
        }
        if ('A' <= ch && ch <= 'F') {
            return ch - 'A' + 10;
        }
        if ('a' <= ch && ch <= 'f') {
            return ch - 'a' + 10;
        }
        return -1;
    }
}