Add support for InfoZIP invented extra fields for Unicode file names and comments. Submitted by Wolfgang Glas. Merge from commons-compress revision 745528

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@745531 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -348,6 +348,9 @@ Fixed bugs:
    VM was running) for files with an unexpected internal structure.
    Bugzilla Report 46559.
 
+ * The zip package now supports the extra fields invented by InfoZIP
+   in order to store Unicode file names and comments.
+
 Other changes:
 --------------
  * A HostInfo task was added performing information on hosts, including info on 

src/main/org/apache/tools/zip/AbstractUnicodeExtraField.java

@@ -0,0 +1,147 @@
+/*
+ *  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.tools.zip;
+
+import java.io.UnsupportedEncodingException;
+import java.util.zip.CRC32;
+import java.util.zip.ZipException;
+
+/**
+ * A common base class for Unicode extra information extra fields.
+ */
+public abstract class AbstractUnicodeExtraField implements ZipExtraField {
+    private long nameCRC32;
+    private byte[] unicodeName;
+    private byte[] data;
+
+    protected AbstractUnicodeExtraField() {
+    }
+
+    /**
+     * Assemble as unicode path extension form the name and encoding
+     * of the orginal zip entry.
+     * 
+     * @param name The file name or comment.
+     * @param zipEncoding The encoding of the filenames in the zip
+     * file, usually <code>"CP437"</code>.
+     */
+    protected AbstractUnicodeExtraField(String name, String zipEncoding) {
+
+        byte[] filename = ZipEncodingHelper.encodeName(name, zipEncoding);
+
+        CRC32 crc32 = new CRC32();
+        crc32.update(filename);
+        nameCRC32 = crc32.getValue();
+
+        try {
+            unicodeName = name.getBytes("UTF-8");
+        } catch (UnsupportedEncodingException e) {
+            throw new RuntimeException("FATAL: UTF-8 encoding not supported.",
+                                       e);
+        }
+    }
+
+    private void assembleData() {
+        if (unicodeName == null) {
+            return;
+        }
+
+        data = new byte[5 + unicodeName.length];
+        // version 1
+        data[0] = 0x01;
+        System.arraycopy(ZipLong.getBytes(nameCRC32), 0, data, 1, 4);
+        System.arraycopy(unicodeName, 0, data, 5, unicodeName.length);
+    }
+
+    /**
+     * @return The CRC32 checksum of the filename or comment as
+     *         encoded in the central directory of the zip file.
+     */
+    public long getNameCRC32() {
+        return nameCRC32;
+    }
+
+    /**
+     * @param nameCRC32 The CRC32 checksum of the filename as encoded
+     *         in the central directory of the zip file to set.
+     */
+    public void setNameCRC32(long nameCRC32) {
+        nameCRC32 = nameCRC32;
+        data = null;
+    }
+
+    /**
+     * @return The utf-8 encoded name.
+     */
+    public byte[] getUnicodeName() {
+        return unicodeName;
+    }
+
+    /**
+     * @param unicodeName The utf-8 encoded name to set.
+     */
+    public void setUnicodeName(byte[] unicodeName) {
+        unicodeName = unicodeName;
+        data = null;
+    }
+
+    public byte[] getCentralDirectoryData() {
+        if (data == null) {
+            this.assembleData();
+        }
+        return data;
+    }
+
+    public ZipShort getCentralDirectoryLength() {
+        if (data == null) {
+            assembleData();
+        }
+        return new ZipShort(data.length);
+    }
+
+    public byte[] getLocalFileDataData() {
+        return getCentralDirectoryData();
+    }
+
+    public ZipShort getLocalFileDataLength() {
+        return getCentralDirectoryLength();
+    }
+
+    public void parseFromLocalFileData(byte[] buffer, int offset, int length)
+        throws ZipException {
+
+        if (length < 5) {
+            throw new ZipException("UniCode path extra data must have at least"
+                                   + " 5 bytes.");
+        }
+
+        int version = buffer[offset];
+
+        if (version != 0x01) {
+            throw new ZipException("Unsupported version [" + version
+                                   + "] for UniCode path extra data.");
+        }
+
+        nameCRC32 = ZipLong.getValue(buffer, offset + 1);
+        unicodeName = new byte[length - 5];
+        System.arraycopy(buffer, offset + 5, unicodeName, 0, length - 5);
+        data = null;
+    }
+
+}

src/main/org/apache/tools/zip/ExtraFieldUtils.java

@@ -44,6 +44,8 @@ public class ExtraFieldUtils {
         implementations = new HashMap();
         register(AsiExtraField.class);
         register(JarMarker.class);
+        register(UnicodePathExtraField.class);
+        register(UnicodeCommentExtraField.class);
     }
 
     /**

src/main/org/apache/tools/zip/UnicodeCommentExtraField.java

@@ -0,0 +1,60 @@
+/*
+ *  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.tools.zip;
+
+/**
+ * Info-ZIP Unicode Comment Extra Field (0x6375):
+ *
+ * <p>Stores the UTF-8 version of the file comment as stored in the
+ * central directory header.</p>
+ *
+ * <pre>
+ *         Value         Size        Description
+ *         -----         ----        -----------
+ *  (UCom) 0x6375        Short       tag for this extra block type ("uc")
+ *         TSize         Short       total data size for this block
+ *         Version       1 byte      version of this extra field, currently 1
+ *         ComCRC32      4 bytes     Comment Field CRC32 Checksum
+ *         UnicodeCom    Variable    UTF-8 version of the entry comment
+ * </pre>
+ */
+public class UnicodeCommentExtraField extends AbstractUnicodeExtraField {
+
+    public static final ZipShort UCOM_ID = new ZipShort(0x6375);
+
+    public UnicodeCommentExtraField () { 
+    }
+
+    /**
+     * Assemble as unicode comment extension form the comment and
+     * encoding of the orginal zip entry.
+     * 
+     * @param name The file name
+     * @param zipEncoding The encoding of the comment in the zip file,
+     * usually <code>"CP437"</code>.
+     */
+    public UnicodeCommentExtraField(String name, String zipEncoding) {
+        super(name, zipEncoding);
+    }
+
+    public ZipShort getHeaderId() {
+        return UCOM_ID;
+    }
+
+}

src/main/org/apache/tools/zip/UnicodePathExtraField.java

@@ -0,0 +1,59 @@
+/*
+ *  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.tools.zip;
+
+/**
+ * Info-ZIP Unicode Path Extra Field (0x7075):
+ *
+ * <p>Stores the UTF-8 version of the file name field as stored in the 
+ * local header and central directory header.</p>
+ *
+ * <pre>
+ *         Value         Size        Description
+ *         -----         ----        -----------
+ * (UPath) 0x7075        Short       tag for this extra block type ("up")
+ *         TSize         Short       total data size for this block
+ *         Version       1 byte      version of this extra field, currently 1
+ *         NameCRC32     4 bytes     File Name Field CRC32 Checksum
+ *         UnicodeName   Variable    UTF-8 version of the entry File Name
+ * </pre>
+ */
+public class UnicodePathExtraField extends AbstractUnicodeExtraField {
+
+    public static final ZipShort UPATH_ID = new ZipShort(0x7075);
+
+    public UnicodePathExtraField () { 
+    }
+
+    /**
+     * Assemble as unicode path extension form the name and encoding
+     * of the orginal zip entry.
+     * 
+     * @param name The file name
+     * @param zipEncoding The encoding of the filename in the zip
+     * file, usually <code>"CP437"</code>.
+     */
+    public UnicodePathExtraField(String name, String zipEncoding) {
+        super(name, zipEncoding);
+    }
+
+    public ZipShort getHeaderId() {
+        return UPATH_ID;
+    }
+}

src/main/org/apache/tools/zip/ZipEncodingHelper.java

@@ -0,0 +1,171 @@
+/*
+ *  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.tools.zip;
+
+import java.nio.ByteBuffer;
+import java.nio.CharBuffer;
+import java.nio.charset.Charset;
+import java.nio.charset.CharsetEncoder;
+import java.nio.charset.CoderResult;
+import java.nio.charset.CodingErrorAction;
+
+/**
+ * Static helper functions for robustly encoding filenames in zip files. 
+ */
+abstract class ZipEncodingHelper {
+
+    /**
+     * Grow a byte buffer, so it has a minimal capacity or at least
+     * the double capacity of the original buffer 
+     * 
+     * @param b The original buffer.
+     * @param newCapacity The minimal requested new capacity.
+     * @return A byte buffer <code>r</code> with
+     *         <code>r.capacity() = max(b.capacity()*2,newCapacity)</code> and
+     *         all the data contained in <code>b</code> copied to the beginning
+     *         of <code>r</code>.
+     *
+     */
+    static ByteBuffer growBuffer(ByteBuffer b, int newCapacity) {
+        b.limit(b.position());
+        b.rewind();
+
+        int c2 = b.capacity() * 2;
+        ByteBuffer on = ByteBuffer.allocate(c2 < newCapacity ? newCapacity : c2);
+
+        on.put(b);
+        return on;
+    }
+
+
+    /**
+     * The hexadecimal digits <code>0,...,9,A,...,F</code> encoded as
+     * ASCII bytes.
+     */
+    private static final byte[] HEX_DIGITS =
+        new byte [] {
+        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41,
+        0x42, 0x43, 0x44, 0x45, 0x46
+    };
+
+    /**
+     * Encode a filename or a comment to a byte array suitable for
+     * storing it to a serialized zip entry.
+     * 
+     * Examples (in pseudo-notation, right hand side is C-style notation):
+     * <pre>
+     *  encodeName("\u20AC_for_Dollar.txt","CP437") = "%U20AC_for_Dollar.txt"
+     *  encodeName("\u00D6lf\u00E4sser.txt","CP437") = "\231lf\204sser.txt"
+     * </pre>
+     * 
+     * @param name The filename or comment with possible non-ASCII
+     * unicode characters.
+     * @param encoding A valid encoding name. The standard zip
+     *                 encoding is <code>"CP437"</code>,
+     *                 <code>"UTF-8"</code> is supported in ZIP file
+     *                 version <code>6.3</code> or later.
+     * @return A byte array containing the mapped file
+     *         name. Unmappable characters or malformed character
+     *         sequences are mapped to a sequence of utf-16 words
+     *         encoded in the format <code>%Uxxxx</code>.
+     */
+    static final byte[] encodeName(String name, String encoding) {
+        Charset cs = Charset.forName(encoding);
+        CharsetEncoder enc = cs.newEncoder();
+
+        enc.onMalformedInput(CodingErrorAction.REPORT);
+        enc.onUnmappableCharacter(CodingErrorAction.REPORT);
+
+        CharBuffer cb = CharBuffer.wrap(name);
+        ByteBuffer out = ByteBuffer.allocate(name.length()
+                                             + (name.length() + 1) / 2);
+
+        while (cb.remaining() > 0) {
+            CoderResult res = enc.encode(cb, out,true);
+
+            if (res.isUnmappable() || res.isMalformed()) {
+
+                // write the unmappable characters in utf-16
+                // pseudo-URL encoding style to ByteBuffer.
+                if (res.length() * 6 > out.remaining()) {
+                    out = growBuffer(out,out.position() + res.length() * 6);
+                }
+
+                for (int i=0; i<res.length(); ++i) {
+                    out.put((byte) '%');
+                    out.put((byte) 'U');
+
+                    char c = cb.get();
+
+                    out.put(HEX_DIGITS[(c >> 12)&0x0f]);
+                    out.put(HEX_DIGITS[(c >> 8)&0x0f]);
+                    out.put(HEX_DIGITS[(c >> 4)&0x0f]);
+                    out.put(HEX_DIGITS[c & 0x0f]);
+                }
+
+            } else if (res.isOverflow()) {
+
+                out = growBuffer(out, 0);
+
+            } else if (res.isUnderflow()) {
+
+                enc.flush(out);
+                break;
+
+            }
+        }
+
+        byte [] ret = new byte[out.position()];
+        out.rewind();
+        out.get(ret);
+
+        return ret;
+    }
+
+    /**
+     * Return, whether a filename or a comment may be encoded to a
+     * byte array suitable for storing it to a serialized zip entry
+     * without any losses.
+     * 
+     * Examples (in pseudo-notation, right hand side is C-style notation):
+     * <pre>
+     *  canEncodeName("\u20AC_for_Dollar.txt","CP437") = false
+     *  canEncodeName("\u20AC_for_Dollar.txt","UTF-8") = true
+     *  canEncodeName("\u00D6lf\u00E4sser.txt","CP437") = true
+     * </pre>
+     * 
+     * @param name The filename or comment with possible non-ASCII
+     * unicode characters.
+     * @param encoding A valid encoding name. The standard zip
+     *                 encoding is <code>"CP437"</code>,
+     *                 <code>"UTF-8"</code> is supported in ZIP file
+     *                 version <code>6.3</code> or later.
+     * @return Whether the given encoding may encode the given name.
+     */
+    static final boolean canEncodeName(String name, String encoding) {
+
+        Charset cs = Charset.forName(encoding);
+
+        CharsetEncoder enc = cs.newEncoder();
+        enc.onMalformedInput(CodingErrorAction.REPORT);
+        enc.onUnmappableCharacter(CodingErrorAction.REPORT);
+
+        return enc.canEncode(name);
+    }
+}