/*
* ====================================================================
* Copyright (c) 2004-2012 TMate Software Ltd. All rights reserved.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://svnkit.com/license.html
* If newer versions of this license are posted there, you may use a
* newer version instead, at your option.
* ====================================================================
*/
package org.tmatesoft.svn.core.internal.util;
import java.nio.CharBuffer;
/**
* @version 1.3
* @author TMate Software Ltd.
*/
public class SVNBase64 {
public static String byteArrayToBase64(byte[] a) {
return byteArrayToBase64(a, false);
}
public static String byteArrayToAltBase64(byte[] a) {
return byteArrayToBase64(a, true);
}
private static String byteArrayToBase64(byte[] a, boolean alternate) {
int aLen = a.length;
int numFullGroups = aLen / 3;
int numBytesInPartialGroup = aLen - 3 * numFullGroups;
int resultLen = 4 * ((aLen + 2) / 3);
StringBuffer result = new StringBuffer(resultLen);
char[] intToAlpha = (alternate ? intToAltBase64 : intToBase64);
// Translate all full groups from byte array elements to SVNBase64
int inCursor = 0;
for (int i = 0; i < numFullGroups; i++) {
int byte0 = a[inCursor++] & 0xff;
int byte1 = a[inCursor++] & 0xff;
int byte2 = a[inCursor++] & 0xff;
result.append(intToAlpha[byte0 >> 2]);
result.append(intToAlpha[(byte0 << 4) & 0x3f | (byte1 >> 4)]);
result.append(intToAlpha[(byte1 << 2) & 0x3f | (byte2 >> 6)]);
result.append(intToAlpha[byte2 & 0x3f]);
}
// Translate partial group if present
if (numBytesInPartialGroup != 0) {
int byte0 = a[inCursor++] & 0xff;
result.append(intToAlpha[byte0 >> 2]);
if (numBytesInPartialGroup == 1) {
result.append(intToAlpha[(byte0 << 4) & 0x3f]);
result.append("==");
} else {
// assert numBytesInPartialGroup == 2;
int byte1 = a[inCursor++] & 0xff;
result.append(intToAlpha[(byte0 << 4) & 0x3f | (byte1 >> 4)]);
result.append(intToAlpha[(byte1 << 2) & 0x3f]);
result.append('=');
}
}
// assert inCursor == a.length;
// assert result.length() == resultLen;
return result.toString();
}
private static final char intToBase64[] = { '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', '+', '/' };
private static final char intToAltBase64[] = { '!', '"', '#', '$', '%',
'&', '\'', '(', ')', ',', '-', '.', ':', ';', '<', '>', '@', '[',
']', '^', '`', '_', '{', '|', '}', '~', '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', '+', '?' };
/**
* Translates the specified SVNBase64 string (as per Preferences.get(byte[]))
* into a byte array.
*
* @throws IllegalArgumentException
* if <tt>s</tt> is not a valid SVNBase64 string.
*/
public static int base64ToByteArray(StringBuffer s, byte[] buffer) {
try {
return base64ToByteArray(s, buffer, false);
} catch (ArrayIndexOutOfBoundsException e) {
throw new IllegalArgumentException("Invalid SVNBase64 string: " + s.toString(), e);
}
}
public static int base64ToByteArray(char[] s, byte[] buffer) {
try {
return base64ToByteArray(s, buffer, false);
} catch (ArrayIndexOutOfBoundsException e) {
throw new IllegalArgumentException("Invalid SVNBase64 string: " + s.toString(), e);
}
}
public static StringBuffer normalizeBase64(StringBuffer in) {
StringBuffer result = new StringBuffer();
for (int i = 0; i < in.length(); i++) {
if (Character.isWhitespace(in.charAt(i))) {
continue;
}
result.append(in.charAt(i));
}
return result;
}
public static char[] normalizeBase64(char[] in) {
final CharBuffer cb = CharBuffer.allocate(in.length);
for (int i = 0; i < in.length; i++) {
if (Character.isWhitespace(in[i])) {
continue;
}
cb.put(in[i]);
}
final char[] result;
try {
if (cb.position() == in.length) {
result = in;
} else {
result = new char[cb.position()];
cb.flip();
cb.get(result);
}
} finally {
if (cb.hasArray()) {
SVNEncodingUtil.clearArray(cb.array());
}
}
return result;
}
private static int base64ToByteArray(StringBuffer sb, byte[] result, boolean alternate) {
return base64ToByteArray(sb.toString().toCharArray(), result, alternate);
}
private static int base64ToByteArray(char[] s, byte[] result, boolean alternate) {
byte[] alphaToInt = (alternate ? altBase64ToInt : base64ToInt);
int sLen = s.length;
int numGroups = sLen / 4;
if (4 * numGroups != sLen) {
numGroups++;
sLen = 4 * numGroups;
}
int missingBytesInLastGroup = 0;
int numFullGroups = numGroups;
if (sLen != 0) {
if (charAt(s, sLen - 1) == '=') {
missingBytesInLastGroup++;
numFullGroups--;
}
if (charAt(s, sLen - 2) == '=')
missingBytesInLastGroup++;
}
int resultLength = 3 * numGroups - missingBytesInLastGroup;
// Translate all full groups from base64 to byte array elements
int inCursor = 0, outCursor = 0;
for (int i = 0; i < numFullGroups; i++) {
int ch0 = alphaToInt[charAt(s, inCursor++)];
int ch1 = alphaToInt[charAt(s, inCursor++)];
int ch2 = alphaToInt[charAt(s, inCursor++)];
int ch3 = alphaToInt[charAt(s, inCursor++)];
result[outCursor++] = (byte) ((ch0 << 2) | (ch1 >> 4));
result[outCursor++] = (byte) ((ch1 << 4) | (ch2 >> 2));
result[outCursor++] = (byte) ((ch2 << 6) | ch3);
}
// Translate partial group, if present
if (missingBytesInLastGroup != 0) {
int ch0 = alphaToInt[charAt(s, inCursor++)];
int ch1 = alphaToInt[charAt(s, inCursor++)];
result[outCursor++] = (byte) ((ch0 << 2) | (ch1 >> 4));
if (missingBytesInLastGroup == 1) {
int ch2 = alphaToInt[charAt(s, inCursor++)];
result[outCursor++] = (byte) ((ch1 << 4) | (ch2 >> 2));
}
}
return resultLength;
}
private static char charAt(char[] array, int index) {
if (index >= array.length) {
return '=';
}
return array[index];
}
/**
* Translates the specified character, which is assumed to be in the "Base
* 64 Alphabet" into its equivalent 6-bit positive integer.
*
* @throws IllegalArgumentException
* or ArrayOutOfBoundsException if c is not in the SVNBase64
* Alphabet.
*/
/*
* private static int base64toInt(char c, byte[] alphaToInt) { int result =
* alphaToInt[c]; if (result < 0) throw new
* IllegalArgumentException("Illegal character " + c); return result; }
*/
/**
* This array is a lookup table that translates unicode characters drawn
* from the "SVNBase64 Alphabet" (as specified in Table 1 of RFC 2045) into
* their 6-bit positive integer equivalents. Characters that are not in the
* SVNBase64 alphabet but fall within the bounds of the array are translated to
* -1.
*/
private static final byte base64ToInt[] = { -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 };
/**
* This array is the analogue of base64ToInt, but for the nonstandard
* variant that avoids the use of uppercase alphabetic characters.
*/
private static final byte altBase64ToInt[] = { -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, 0, 1, 2, 3, 4, 5, 6, 7, 8, -1,
62, 9, 10, 11, -1, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 12, 13,
14, -1, 15, 63, 16, -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, 17, -1, 18,
19, 21, 20, 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, 22, 23, 24, 25 };
}