/*******************************************************************************
* Copyright (c) 2007, 2013 Wind River Systems, Inc. and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Wind River Systems - initial API and implementation
*******************************************************************************/
package org.eclipse.tcf.core;
/**
* Methods for translating Base64 encoded strings to byte arrays and back.
* @noinstantiate This class is not intended to be instantiated by clients.
*/
public final class Base64 {
public static char[] toBase64(byte[] buf, int pos, int len) {
char[] out_buf = new char[4 * ((len + 2) / 3)];
int end = pos + len;
int out_pos = 0;
while (pos < end) {
int byte0 = buf[pos++] & 0xff;
out_buf[out_pos++] = int2char[byte0 >> 2];
if (pos == end) {
out_buf[out_pos++] = int2char[(byte0 << 4) & 0x3f];
out_buf[out_pos++] = '=';
out_buf[out_pos++] = '=';
}
else {
int byte1 = buf[pos++] & 0xff;
out_buf[out_pos++] = int2char[(byte0 << 4) & 0x3f | (byte1 >> 4)];
if (pos == end) {
out_buf[out_pos++] = int2char[(byte1 << 2) & 0x3f];
out_buf[out_pos++] = '=';
}
else {
int byte2 = buf[pos++] & 0xff;
out_buf[out_pos++] = int2char[(byte1 << 2) & 0x3f | (byte2 >> 6)];
out_buf[out_pos++] = int2char[byte2 & 0x3f];
}
}
}
assert out_pos == out_buf.length;
return out_buf;
}
public static void toByteArray(byte[] buf, int offs, int size, char[] inp) {
int out_pos = offs;
if (inp != null) {
int inp_len = inp.length;
if (inp_len % 4 != 0) {
throw new IllegalArgumentException(
"BASE64 string length must be a multiple of four.");
}
int out_len = inp_len / 4 * 3;
if (inp_len > 0 && inp[inp_len - 1] == '=') {
out_len--;
if (inp[inp_len - 2] == '=') {
out_len--;
}
}
if (out_len > size) {
throw new IllegalArgumentException(
"BASE64 data array is longer then destination buffer.");
}
int inp_pos = 0;
while (inp_pos < inp_len) {
int n0, n1, n2, n3;
char ch0 = inp[inp_pos++];
char ch1 = inp[inp_pos++];
char ch2 = inp[inp_pos++];
char ch3 = inp[inp_pos++];
if (ch0 >= char2int.length || (n0 = char2int[ch0]) < 0) {
throw new IllegalArgumentException("Illegal character " + ch0);
}
if (ch1 >= char2int.length || (n1 = char2int[ch1]) < 0) {
throw new IllegalArgumentException("Illegal character " + ch1);
}
buf[out_pos++] = (byte)((n0 << 2) | (n1 >> 4));
if (ch2 == '=') break;
if (ch2 >= char2int.length || (n2 = char2int[ch2]) < 0) {
throw new IllegalArgumentException("Illegal character " + ch2);
}
buf[out_pos++] = (byte)((n1 << 4) | (n2 >> 2));
if (ch3 == '=') break;
if (ch3 >= char2int.length || (n3 = char2int[ch3]) < 0) {
throw new IllegalArgumentException("Illegal character " + ch3);
}
buf[out_pos++] = (byte)((n2 << 6) | n3);
}
assert out_pos == offs + out_len;
}
while (out_pos < offs + size) buf[out_pos++] = 0;
}
public static byte[] toByteArray(char[] inp) {
int inp_len = inp.length;
int out_len = inp_len / 4 * 3;
if (inp_len > 0 && inp[inp_len - 1] == '=') {
out_len--;
if (inp[inp_len - 2] == '=') {
out_len--;
}
}
byte[] buf = new byte[out_len];
toByteArray(buf, 0, buf.length, inp);
return buf;
}
/*
* See RFC 2045.
*/
private static final char int2char[] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/'
};
/*
* See RFC 2045
*/
private static final byte char2int[] = {
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, 62, -1, -1, -1, 63,
52, 53, 54, 55, 56, 57, 58, 59,
60, 61, -1, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22,
23, 24, 25, -1, -1, -1, -1, -1,
-1, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51
};
}