| /**************************************************************** |
| * Licensed to the Apache Software Foundation (ASF) under one * |
| * or more contributor license agreements. See the NOTICE file * |
| * distributed with this work for additional information * |
| * regarding copyright ownership. The ASF licenses this file * |
| * to you under the Apache License, Version 2.0 (the * |
| * "License"); you may not use this file except in compliance * |
| * with the License. You may obtain a copy of the License at * |
| * * |
| * http://www.apache.org/licenses/LICENSE-2.0 * |
| * * |
| * Unless required by applicable law or agreed to in writing, * |
| * software distributed under the License is distributed on an * |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * |
| * KIND, either express or implied. See the License for the * |
| * specific language governing permissions and limitations * |
| * under the License. * |
| ****************************************************************/ |
| |
| package org.apache.james.mime4j.util; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| /** |
| * Utility methods related to codecs. |
| */ |
| public class CodecUtil { |
| |
| |
| public static final byte[] CRLF = {'\r', '\n'}; |
| |
| public static final byte[] CRLF_CRLF = {'\r', '\n', '\r', '\n'}; |
| |
| private static final int DEFAULT_ENCODING_BUFFER_SIZE = 1024; |
| |
| private static final byte SPACE = 0x20; |
| private static final byte EQUALS = 0x3D; |
| private static final byte CR = 0x0D; |
| private static final byte LF = 0x0A; |
| private static final byte QUOTED_PRINTABLE_LAST_PLAIN = 0x7E; |
| private static final int QUOTED_PRINTABLE_MAX_LINE_LENGTH = 76; |
| private static final int QUOTED_PRINTABLE_OCTETS_PER_ESCAPE = 3; |
| private static final byte[] HEX_DIGITS = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; |
| |
| /** |
| * Copies the contents of one stream to the other. |
| * @param in not null |
| * @param out not null |
| * @throws IOException |
| */ |
| public static void copy(final InputStream in, final OutputStream out) throws IOException { |
| final byte[] buffer = new byte[DEFAULT_ENCODING_BUFFER_SIZE]; |
| int inputLength; |
| while (-1 != (inputLength = in.read(buffer))) { |
| out.write(buffer, 0, inputLength); |
| } |
| } |
| |
| /** |
| * Encodes the given stream using Quoted-Printable. |
| * This assumes that text is binary and therefore escapes |
| * all line endings. |
| * @param in not null |
| * @param out not null |
| * @throws IOException |
| */ |
| public static void encodeQuotedPrintableBinary(final InputStream in, final OutputStream out) throws IOException { |
| |
| BinaryQuotedPrintableEncoder encoder = new BinaryQuotedPrintableEncoder(DEFAULT_ENCODING_BUFFER_SIZE); |
| encoder.encode(in, out); |
| } |
| |
| private static final class BinaryQuotedPrintableEncoder { |
| private final byte[] inBuffer; |
| private final byte[] outBuffer; |
| |
| private int nextSoftBreak; |
| private int inputIndex; |
| private int outputIndex; |
| private int inputLength; |
| private InputStream in; |
| private OutputStream out; |
| |
| |
| public BinaryQuotedPrintableEncoder(int bufferSize) { |
| inBuffer = new byte[bufferSize]; |
| outBuffer = new byte[3*bufferSize]; |
| inputLength = 0; |
| outputIndex = 0; |
| nextSoftBreak = QUOTED_PRINTABLE_MAX_LINE_LENGTH + 1; |
| in = null; |
| out = null; |
| } |
| |
| public void encode(final InputStream in, final OutputStream out) throws IOException { |
| this.in = in; |
| this.out = out; |
| nextSoftBreak = QUOTED_PRINTABLE_MAX_LINE_LENGTH + 1; |
| read(); |
| while(inputLength > -1) { |
| while (inputIndex < inputLength) { |
| final byte next = inBuffer[inputIndex]; |
| encode(next); |
| inputIndex++; |
| } |
| read(); |
| } |
| flushOutput(); |
| } |
| |
| private void read() throws IOException { |
| inputLength = in.read(inBuffer); |
| inputIndex = 0; |
| } |
| |
| private void encode(byte next) throws IOException { |
| if (next <= SPACE) { |
| escape(next); |
| } else if (next > QUOTED_PRINTABLE_LAST_PLAIN) { |
| escape(next); |
| } else if (next == EQUALS) { |
| escape(next); |
| } else { |
| plain(next); |
| } |
| } |
| |
| private void plain(byte next) throws IOException { |
| if (--nextSoftBreak <= 1) { |
| softBreak(); |
| } |
| write(next); |
| } |
| |
| private void escape(byte next) throws IOException { |
| if (--nextSoftBreak <= QUOTED_PRINTABLE_OCTETS_PER_ESCAPE) { |
| softBreak(); |
| } |
| write(EQUALS); |
| --nextSoftBreak; |
| write(HEX_DIGITS[next >> 4]); |
| --nextSoftBreak; |
| write(HEX_DIGITS[next % 0x10]); |
| } |
| |
| private void write(byte next) throws IOException { |
| outBuffer[outputIndex] = next; |
| if (outputIndex >= outBuffer.length) { |
| flushOutput(); |
| } else { |
| outputIndex++; |
| } |
| } |
| |
| private void softBreak() throws IOException { |
| write(EQUALS); |
| write(CR); |
| write(LF); |
| nextSoftBreak = QUOTED_PRINTABLE_MAX_LINE_LENGTH; |
| } |
| |
| private void flushOutput() throws IOException { |
| if (outputIndex < outBuffer.length) { |
| out.write(outBuffer, 0, outputIndex); |
| } else { |
| out.write(outBuffer); |
| } |
| outputIndex = 0; |
| } |
| } |
| |
| /** |
| * Encodes the given stream using Base64. |
| * @param in not null |
| * @param out not null |
| * @throws IOException |
| */ |
| public static void encodeBase64(final InputStream in, final OutputStream out) throws IOException { |
| Base64Encoder encoder = new Base64Encoder(DEFAULT_ENCODING_BUFFER_SIZE); |
| encoder.encode(in, out); |
| } |
| |
| private static final class Base64Encoder { |
| private static final int MASK = 0x3F; |
| private static final int FIRST_MASK = MASK << 18; |
| private static final int SECOND_MASK = MASK << 12; |
| private static final int THIRD_MASK = MASK << 6; |
| private static final int FORTH_MASK = MASK; |
| |
| private static final byte[] ENCODING = {'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 final byte[] in; |
| private final byte[] out; |
| |
| public Base64Encoder(final int inputBufferSize) { |
| in = new byte[inputBufferSize]; |
| int outputBufferSize = ((int) Math.floor((4*inputBufferSize) / 3f) + 3); |
| outputBufferSize = outputBufferSize + 2 * (int) Math.floor(outputBufferSize / 76f); |
| out = new byte[outputBufferSize]; |
| } |
| |
| public void encode(final InputStream inStream, final OutputStream outStream) throws IOException { |
| int inputLength = inStream.read(in); |
| while (inputLength > -1) { |
| int outputLength = encodeInputBuffer(inputLength); |
| if (outputLength > 0) { |
| outStream.write(out, 0, outputLength); |
| } |
| inputLength = inStream.read(in); |
| } |
| } |
| |
| private int encodeInputBuffer(final int inputLength) { |
| if (inputLength == 0) { |
| return 0; |
| } |
| int inputIndex = 0; |
| int outputIndex = 0; |
| while (inputLength - inputIndex > 2) { |
| int one = (toInt(in[inputIndex++]) << 16); |
| int two = (toInt(in[inputIndex++]) << 8); |
| int three = toInt(in[inputIndex++]); |
| int quantum = one | two | three; |
| int index = (quantum & FIRST_MASK) >> 18; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & SECOND_MASK) >> 12; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & THIRD_MASK) >> 6; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & FORTH_MASK); |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| } |
| |
| switch (inputLength - inputIndex) { |
| case 1: |
| int quantum = in[inputIndex++] << 16; |
| int index = (quantum & FIRST_MASK) >> 18; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & SECOND_MASK) >> 12; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| outputIndex = setResult(out, outputIndex, (byte) '='); |
| outputIndex = setResult(out, outputIndex, (byte) '='); |
| break; |
| |
| case 2: |
| quantum = (in[inputIndex++] << 16) + (in[inputIndex++] << 8); |
| index = (quantum & FIRST_MASK) >> 18; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & SECOND_MASK) >> 12; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| index = (quantum & THIRD_MASK) >> 6; |
| outputIndex = setResult(out, outputIndex, ENCODING[index]); |
| outputIndex = setResult(out, outputIndex, (byte) '='); |
| break; |
| } |
| |
| return outputIndex; |
| } |
| |
| private int toInt(byte b) { |
| return 255 & b; |
| } |
| |
| private int setResult(byte[] results, int outputIndex, byte value) { |
| results[outputIndex++] = value; |
| outputIndex = checkLineLength(results, outputIndex); |
| return outputIndex; |
| } |
| |
| private int checkLineLength(byte[] results, int outputIndex) { |
| if (outputIndex == 76 || outputIndex > 76 && (outputIndex - 2*Math.floor(outputIndex/76f - 1)) % 76 == 0) { |
| results[outputIndex++] = '\r'; |
| results[outputIndex++] = '\n'; |
| } |
| return outputIndex; |
| } |
| } |
| } |