/*
* Funambol is a mobile platform developed by Funambol, Inc.
* Copyright (C) 2003 - 2007 Funambol, Inc.
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU Affero General Public License version 3 as published by
* the Free Software Foundation with the addition of the following permission
* added to Section 15 as permitted in Section 7(a): FOR ANY PART OF THE COVERED
* WORK IN WHICH THE COPYRIGHT IS OWNED BY FUNAMBOL, FUNAMBOL DISCLAIMS THE
* WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
*
* This program 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 for more
* details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA.
*
* You can contact Funambol, Inc. headquarters at 643 Bair Island Road, Suite
* 305, Redwood City, CA 94063, USA, or at email address info@funambol.com.
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License version 3.
*
* In accordance with Section 7(b) of the GNU Affero General Public License
* version 3, these Appropriate Legal Notices must retain the display of the
* "Powered by Funambol" logo. If the display of the logo is not reasonably
* feasible for technical reasons, the Appropriate Legal Notices must display
* the words "Powered by Funambol".
*/
package com.funambol.util;
import java.io.ByteArrayOutputStream;
import java.io.UnsupportedEncodingException;
/**
* A class containing static methods to perform decoding from <b>quoted
* printable</b> content transfer encoding and to encode into
*/
public class QuotedPrintable {
private static byte HT = 0x09; // \t
private static byte LF = 0x0A; // \n
private static byte CR = 0x0D; // \r
private static final byte ESCAPE_CHAR = '=';
private static final byte TAB = 9;
private static final byte SPACE = 32;
/**
* BitSet of printable characters as defined in RFC 1521.
*/
private static final boolean SAFE_CHARS[] = new boolean [256];
static {
for (int i = 33; i <= 60; i++) {
SAFE_CHARS[i] = true;
}
for (int i = 62; i <= 126; i++) {
SAFE_CHARS[i] = true;
}
SAFE_CHARS[TAB] = true;
SAFE_CHARS[SPACE] = true;
}
/**
* A method to decode quoted printable encoded data.
* It overrides the same input byte array to save memoty. Can be done
* because the result is surely smaller than the input.
*
* @param qp
* a byte array to decode.
* @return the length of the decoded array.
*/
public static int decode(byte [] qp) {
int qplen = qp.length;
int retlen = 0;
for (int i=0; i < qplen; i++) {
// Handle encoded chars
if (qp[i] == '=') {
if (qplen - i > 2) {
// The sequence can be complete, check it
if (qp[i+1] == CR && qp[i+2] == LF) {
// soft line break, ignore it
i += 2;
continue;
} else if (isHexDigit(qp[i+1]) && isHexDigit(qp[i+2]) ) {
// convert the number into an integer, taking
// the ascii digits stored in the array.
qp[retlen++]=(byte)(getHexValue(qp[i+1])*16
+ getHexValue(qp[i+2]));
i += 2;
continue;
} else {
Log.error("decode: Invalid sequence = " + qp[i+1] + qp[i+2]);
}
}
// In all wrong cases leave the original bytes
// (see RFC 2045). They can be incomplete sequence,
// or a '=' followed by non hex digit.
}
// RFC 2045 says to exclude control characters mistakenly
// present (unencoded) in the encoded stream.
// As an exception, we keep unencoded tabs (0x09)
if( (qp[i] >= 0x20 && qp[i] <= 0x7f) ||
qp[i] == HT || qp[i] == CR || qp[i] == LF) {
qp[retlen++] = qp[i];
}
}
return retlen;
}
private static boolean isHexDigit(byte b) {
return ( (b>=0x30 && b<=0x39) || (b>=0x41&&b<=0x46) );
}
private static byte getHexValue(byte b) {
return (byte)Character.digit((char)b, 16);
}
public static String decode(byte[] qp, String enc) {
int len=decode(qp);
try {
return new String(qp, 0, len, enc);
} catch (UnsupportedEncodingException e) {
Log.error("qp.decode: "+ enc + " not supported. " + e.toString());
return new String(qp, 0, len);
}
}
/**
* Encodes an array of bytes into an array of quoted-printable 7-bit characters.
* @param bytes Array of bytes to be encoded
* @return Array of bytes containing quoted-printable representation of the input
*/
public static final byte[] encode(byte[] bytes) {
if (bytes == null) {
return null;
}
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
for (int i = 0; i < bytes.length; i++) {
int b = bytes[i];
if (b < 0) {
b = 256 + b;
}
if (SAFE_CHARS[b]) {
buffer.write(b);
} else {
buffer.write(ESCAPE_CHAR);
String hexValue = Integer.toHexString(b);
// The value must be printed as double digits
if (hexValue.length() < 2) {
hexValue = "0" + hexValue;
}
// Now print it
byte values[] = hexValue.toUpperCase().getBytes();
for(int j=0;j<values.length;++j) {
buffer.write(values[j]);
}
}
}
return buffer.toByteArray();
}
/**
* Encodes a String into a String of quoted-printable 7-bit characters.
* @param str string to be encoded
* @param enc the encoding in which the string is encoded
* @return a string containing quoted-printable representation of the input
*/
public static final String encode(String str, String enc) throws UnsupportedEncodingException {
if (str == null) {
return null;
}
return new String(encode(str.getBytes(enc)), enc);
}
/**
* Encodes a String into a String of quoted-printable 7-bit characters.
* @param str string to be encoded
* @return a string containing quoted-printable representation of the input
*/
public static final String encode(String str) throws UnsupportedEncodingException {
if (str == null) {
return null;
}
return new String(encode(str.getBytes()));
}
}