diff options
Diffstat (limited to 'java/com/android/voicemailomtp/src/org/apache/james/mime4j/decoder/QuotedPrintableInputStream.java')
| -rw-r--r-- | java/com/android/voicemailomtp/src/org/apache/james/mime4j/decoder/QuotedPrintableInputStream.java | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/java/com/android/voicemailomtp/src/org/apache/james/mime4j/decoder/QuotedPrintableInputStream.java b/java/com/android/voicemailomtp/src/org/apache/james/mime4j/decoder/QuotedPrintableInputStream.java new file mode 100644 index 000000000..e43f398f9 --- /dev/null +++ b/java/com/android/voicemailomtp/src/org/apache/james/mime4j/decoder/QuotedPrintableInputStream.java @@ -0,0 +1,229 @@ +/**************************************************************** + * 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.decoder; + +import java.io.IOException; +import java.io.InputStream; + +//BEGIN android-changed: Stubbing out logging +import org.apache.james.mime4j.Log; +import org.apache.james.mime4j.LogFactory; +//END android-changed + +/** + * Performs Quoted-Printable decoding on an underlying stream. + * + * + * + * @version $Id: QuotedPrintableInputStream.java,v 1.3 2004/11/29 13:15:47 ntherning Exp $ + */ +public class QuotedPrintableInputStream extends InputStream { + private static Log log = LogFactory.getLog(QuotedPrintableInputStream.class); + + private InputStream stream; + ByteQueue byteq = new ByteQueue(); + ByteQueue pushbackq = new ByteQueue(); + private byte state = 0; + + public QuotedPrintableInputStream(InputStream stream) { + this.stream = stream; + } + + /** + * Closes the underlying stream. + * + * @throws IOException on I/O errors. + */ + public void close() throws IOException { + stream.close(); + } + + public int read() throws IOException { + fillBuffer(); + if (byteq.count() == 0) + return -1; + else { + byte val = byteq.dequeue(); + if (val >= 0) + return val; + else + return val & 0xFF; + } + } + + /** + * Pulls bytes out of the underlying stream and places them in the + * pushback queue. This is necessary (vs. reading from the + * underlying stream directly) to detect and filter out "transport + * padding" whitespace, i.e., all whitespace that appears immediately + * before a CRLF. + * + * @throws IOException Underlying stream threw IOException. + */ + private void populatePushbackQueue() throws IOException { + //Debug.verify(pushbackq.count() == 0, "PopulatePushbackQueue called when pushback queue was not empty!"); + + if (pushbackq.count() != 0) + return; + + while (true) { + int i = stream.read(); + switch (i) { + case -1: + // stream is done + pushbackq.clear(); // discard any whitespace preceding EOF + return; + case ' ': + case '\t': + pushbackq.enqueue((byte)i); + break; + case '\r': + case '\n': + pushbackq.clear(); // discard any whitespace preceding EOL + pushbackq.enqueue((byte)i); + return; + default: + pushbackq.enqueue((byte)i); + return; + } + } + } + + /** + * Causes the pushback queue to get populated if it is empty, then + * consumes and decodes bytes out of it until one or more bytes are + * in the byte queue. This decoding step performs the actual QP + * decoding. + * + * @throws IOException Underlying stream threw IOException. + */ + private void fillBuffer() throws IOException { + byte msdChar = 0; // first digit of escaped num + while (byteq.count() == 0) { + if (pushbackq.count() == 0) { + populatePushbackQueue(); + if (pushbackq.count() == 0) + return; + } + + byte b = (byte)pushbackq.dequeue(); + + switch (state) { + case 0: // start state, no bytes pending + if (b != '=') { + byteq.enqueue(b); + break; // state remains 0 + } else { + state = 1; + break; + } + case 1: // encountered "=" so far + if (b == '\r') { + state = 2; + break; + } else if ((b >= '0' && b <= '9') || (b >= 'A' && b <= 'F') || (b >= 'a' && b <= 'f')) { + state = 3; + msdChar = b; // save until next digit encountered + break; + } else if (b == '=') { + /* + * Special case when == is encountered. + * Emit one = and stay in this state. + */ + if (log.isWarnEnabled()) { + log.warn("Malformed MIME; got =="); + } + byteq.enqueue((byte)'='); + break; + } else { + if (log.isWarnEnabled()) { + log.warn("Malformed MIME; expected \\r or " + + "[0-9A-Z], got " + b); + } + state = 0; + byteq.enqueue((byte)'='); + byteq.enqueue(b); + break; + } + case 2: // encountered "=\r" so far + if (b == '\n') { + state = 0; + break; + } else { + if (log.isWarnEnabled()) { + log.warn("Malformed MIME; expected " + + (int)'\n' + ", got " + b); + } + state = 0; + byteq.enqueue((byte)'='); + byteq.enqueue((byte)'\r'); + byteq.enqueue(b); + break; + } + case 3: // encountered =<digit> so far; expecting another <digit> to complete the octet + if ((b >= '0' && b <= '9') || (b >= 'A' && b <= 'F') || (b >= 'a' && b <= 'f')) { + byte msd = asciiCharToNumericValue(msdChar); + byte low = asciiCharToNumericValue(b); + state = 0; + byteq.enqueue((byte)((msd << 4) | low)); + break; + } else { + if (log.isWarnEnabled()) { + log.warn("Malformed MIME; expected " + + "[0-9A-Z], got " + b); + } + state = 0; + byteq.enqueue((byte)'='); + byteq.enqueue(msdChar); + byteq.enqueue(b); + break; + } + default: // should never happen + log.error("Illegal state: " + state); + state = 0; + byteq.enqueue(b); + break; + } + } + } + + /** + * Converts '0' => 0, 'A' => 10, etc. + * @param c ASCII character value. + * @return Numeric value of hexadecimal character. + */ + private byte asciiCharToNumericValue(byte c) { + if (c >= '0' && c <= '9') { + return (byte)(c - '0'); + } else if (c >= 'A' && c <= 'Z') { + return (byte)(0xA + (c - 'A')); + } else if (c >= 'a' && c <= 'z') { + return (byte)(0xA + (c - 'a')); + } else { + /* + * This should never happen since all calls to this method + * are preceded by a check that c is in [0-9A-Za-z] + */ + throw new IllegalArgumentException((char) c + + " is not a hexadecimal digit"); + } + } + +} |