| /* |
| * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @(#)QPDecoderStream.java 1.9 02/04/02 |
| */ |
| |
| |
| |
| package com.sun.xml.internal.messaging.saaj.packaging.mime.util; |
| |
| import java.io.*; |
| |
| /** |
| * This class implements a QP Decoder. It is implemented as |
| * a FilterInputStream, so one can just wrap this class around |
| * any input stream and read bytes from this filter. The decoding |
| * is done as the bytes are read out. |
| * |
| * @author John Mani |
| */ |
| |
| public class QPDecoderStream extends FilterInputStream { |
| protected byte[] ba = new byte[2]; |
| protected int spaces = 0; |
| |
| /** |
| * Create a Quoted Printable decoder that decodes the specified |
| * input stream. |
| * @param in the input stream |
| */ |
| public QPDecoderStream(InputStream in) { |
| super(new PushbackInputStream(in, 2)); // pushback of size=2 |
| } |
| |
| /** |
| * Read the next decoded byte from this input stream. The byte |
| * is returned as an <code>int</code> in the range <code>0</code> |
| * to <code>255</code>. If no byte is available because the end of |
| * the stream has been reached, the value <code>-1</code> is returned. |
| * This method blocks until input data is available, the end of the |
| * stream is detected, or an exception is thrown. |
| * |
| * @return the next byte of data, or <code>-1</code> if the end of the |
| * stream is reached. |
| * @exception IOException if an I/O error occurs. |
| */ |
| @Override |
| public int read() throws IOException { |
| if (spaces > 0) { |
| // We have cached space characters, return one |
| spaces--; |
| return ' '; |
| } |
| |
| int c = in.read(); |
| |
| if (c == ' ') { |
| // Got space, keep reading till we get a non-space char |
| while ((c = in.read()) == ' ') |
| spaces++; |
| |
| if (c == '\r' || c == '\n' || c == -1) |
| // If the non-space char is CR/LF/EOF, the spaces we got |
| // so far is junk introduced during transport. Junk 'em. |
| spaces = 0; |
| else { |
| // The non-space char is NOT CR/LF, the spaces are valid. |
| ((PushbackInputStream)in).unread(c); |
| c = ' '; |
| } |
| return c; // return either <SPACE> or <CR/LF> |
| } |
| else if (c == '=') { |
| // QP Encoded atom. Decode the next two bytes |
| int a = in.read(); |
| |
| if (a == '\n') { |
| /* Hmm ... not really confirming QP encoding, but lets |
| * allow this as a LF terminated encoded line .. and |
| * consider this a soft linebreak and recurse to fetch |
| * the next char. |
| */ |
| return read(); |
| } else if (a == '\r') { |
| // Expecting LF. This forms a soft linebreak to be ignored. |
| int b = in.read(); |
| if (b != '\n') |
| /* Not really confirming QP encoding, but |
| * lets allow this as well. |
| */ |
| ((PushbackInputStream)in).unread(b); |
| return read(); |
| } else if (a == -1) { |
| // Not valid QP encoding, but we be nice and tolerant here ! |
| return -1; |
| } else { |
| ba[0] = (byte)a; |
| ba[1] = (byte)in.read(); |
| try { |
| return ASCIIUtility.parseInt(ba, 0, 2, 16); |
| } catch (NumberFormatException nex) { |
| /* |
| System.err.println( |
| "Illegal characters in QP encoded stream: " + |
| ASCIIUtility.toString(ba, 0, 2) |
| ); |
| */ |
| |
| ((PushbackInputStream)in).unread(ba); |
| return c; |
| } |
| } |
| } |
| return c; |
| } |
| |
| /** |
| * Reads up to <code>len</code> decoded bytes of data from this input stream |
| * into an array of bytes. This method blocks until some input is |
| * available. |
| * <p> |
| * |
| * @param buf the buffer into which the data is read. |
| * @param off the start offset of the data. |
| * @param len the maximum number of bytes read. |
| * @return the total number of bytes read into the buffer, or |
| * <code>-1</code> if there is no more data because the end of |
| * the stream has been reached. |
| * @exception IOException if an I/O error occurs. |
| */ |
| @Override |
| public int read(byte[] buf, int off, int len) throws IOException { |
| int i, c; |
| for (i = 0; i < len; i++) { |
| if ((c = read()) == -1) { |
| if (i == 0) // At end of stream, so we should |
| i = -1; // return -1 , NOT 0. |
| break; |
| } |
| buf[off+i] = (byte)c; |
| } |
| return i; |
| } |
| |
| /** |
| * Tests if this input stream supports marks. Currently this class |
| * does not support marks |
| */ |
| @Override |
| public boolean markSupported() { |
| return false; |
| } |
| |
| /** |
| * Returns the number of bytes that can be read from this input |
| * stream without blocking. The QP algorithm does not permit |
| * a priori knowledge of the number of bytes after decoding, so |
| * this method just invokes the <code>available</code> method |
| * of the original input stream. |
| */ |
| @Override |
| public int available() throws IOException { |
| // This is bogus ! We don't really know how much |
| // bytes are available *after* decoding |
| return in.available(); |
| } |
| |
| /**** begin TEST program |
| public static void main(String argv[]) throws Exception { |
| FileInputStream infile = new FileInputStream(argv[0]); |
| QPDecoderStream decoder = new QPDecoderStream(infile); |
| int c; |
| |
| while ((c = decoder.read()) != -1) |
| System.out.print((char)c); |
| System.out.println(); |
| } |
| *** end TEST program ****/ |
| } |