| /* |
| * 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.jasper.xmlparser; |
| |
| import java.io.InputStream; |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.UTFDataFormatException; |
| import org.apache.jasper.compiler.Localizer; |
| |
| /** |
| * @author Andy Clark, IBM |
| * |
| * @version $Id$ |
| */ |
| public class UTF8Reader |
| extends Reader { |
| |
| private org.apache.commons.logging.Log log= |
| org.apache.commons.logging.LogFactory.getLog( UTF8Reader.class ); |
| |
| // |
| // Constants |
| // |
| |
| /** Default byte buffer size (2048). */ |
| public static final int DEFAULT_BUFFER_SIZE = 2048; |
| |
| // debugging |
| |
| /** Debug read. */ |
| private static final boolean DEBUG_READ = false; |
| |
| // |
| // Data |
| // |
| |
| /** Input stream. */ |
| protected InputStream fInputStream; |
| |
| /** Byte buffer. */ |
| protected byte[] fBuffer; |
| |
| /** Offset into buffer. */ |
| protected int fOffset; |
| |
| /** Surrogate character. */ |
| private int fSurrogate = -1; |
| |
| // |
| // Constructors |
| // |
| |
| /** |
| * Constructs a UTF-8 reader from the specified input stream, |
| * buffer size and MessageFormatter. |
| * |
| * @param inputStream The input stream. |
| * @param size The initial buffer size. |
| */ |
| public UTF8Reader(InputStream inputStream, int size) { |
| fInputStream = inputStream; |
| fBuffer = new byte[size]; |
| } |
| |
| // |
| // Reader methods |
| // |
| |
| /** |
| * Read a single character. This method will block until a character is |
| * available, an I/O error occurs, or the end of the stream is reached. |
| * |
| * <p> Subclasses that intend to support efficient single-character input |
| * should override this method. |
| * |
| * @return The character read, as an integer in the range 0 to 16383 |
| * (<tt>0x00-0xffff</tt>), or -1 if the end of the stream has |
| * been reached |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public int read() throws IOException { |
| |
| // decode character |
| int c = fSurrogate; |
| if (fSurrogate == -1) { |
| // NOTE: We use the index into the buffer if there are remaining |
| // bytes from the last block read. -Ac |
| int index = 0; |
| |
| // get first byte |
| int b0 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b0 == -1) { |
| return -1; |
| } |
| |
| // UTF-8: [0xxx xxxx] |
| // Unicode: [0000 0000] [0xxx xxxx] |
| if (b0 < 0x80) { |
| c = (char)b0; |
| } |
| |
| // UTF-8: [110y yyyy] [10xx xxxx] |
| // Unicode: [0000 0yyy] [yyxx xxxx] |
| else if ((b0 & 0xE0) == 0xC0) { |
| int b1 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b1 == -1) { |
| expectedByte(2, 2); |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| invalidByte(2, 2, b1); |
| } |
| c = ((b0 << 6) & 0x07C0) | (b1 & 0x003F); |
| } |
| |
| // UTF-8: [1110 zzzz] [10yy yyyy] [10xx xxxx] |
| // Unicode: [zzzz yyyy] [yyxx xxxx] |
| else if ((b0 & 0xF0) == 0xE0) { |
| int b1 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b1 == -1) { |
| expectedByte(2, 3); |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| invalidByte(2, 3, b1); |
| } |
| int b2 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b2 == -1) { |
| expectedByte(3, 3); |
| } |
| if ((b2 & 0xC0) != 0x80) { |
| invalidByte(3, 3, b2); |
| } |
| c = ((b0 << 12) & 0xF000) | ((b1 << 6) & 0x0FC0) | |
| (b2 & 0x003F); |
| } |
| |
| // UTF-8: [1111 0uuu] [10uu zzzz] [10yy yyyy] [10xx xxxx]* |
| // Unicode: [1101 10ww] [wwzz zzyy] (high surrogate) |
| // [1101 11yy] [yyxx xxxx] (low surrogate) |
| // * uuuuu = wwww + 1 |
| else if ((b0 & 0xF8) == 0xF0) { |
| int b1 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b1 == -1) { |
| expectedByte(2, 4); |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| invalidByte(2, 3, b1); |
| } |
| int b2 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b2 == -1) { |
| expectedByte(3, 4); |
| } |
| if ((b2 & 0xC0) != 0x80) { |
| invalidByte(3, 3, b2); |
| } |
| int b3 = index == fOffset |
| ? fInputStream.read() : fBuffer[index++] & 0x00FF; |
| if (b3 == -1) { |
| expectedByte(4, 4); |
| } |
| if ((b3 & 0xC0) != 0x80) { |
| invalidByte(4, 4, b3); |
| } |
| int uuuuu = ((b0 << 2) & 0x001C) | ((b1 >> 4) & 0x0003); |
| if (uuuuu > 0x10) { |
| invalidSurrogate(uuuuu); |
| } |
| int wwww = uuuuu - 1; |
| int hs = 0xD800 | |
| ((wwww << 6) & 0x03C0) | ((b1 << 2) & 0x003C) | |
| ((b2 >> 4) & 0x0003); |
| int ls = 0xDC00 | ((b2 << 6) & 0x03C0) | (b3 & 0x003F); |
| c = hs; |
| fSurrogate = ls; |
| } |
| |
| // error |
| else { |
| invalidByte(1, 1, b0); |
| } |
| } |
| |
| // use surrogate |
| else { |
| fSurrogate = -1; |
| } |
| |
| // return character |
| if (DEBUG_READ) { |
| if (log.isDebugEnabled()) |
| log.debug("read(): 0x"+Integer.toHexString(c)); |
| } |
| return c; |
| |
| } // read():int |
| |
| /** |
| * Read characters into a portion of an array. This method will block |
| * until some input is available, an I/O error occurs, or the end of the |
| * stream is reached. |
| * |
| * @param ch Destination buffer |
| * @param offset Offset at which to start storing characters |
| * @param length Maximum number of characters to read |
| * |
| * @return The number of characters read, or -1 if the end of the |
| * stream has been reached |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public int read(char ch[], int offset, int length) throws IOException { |
| |
| // handle surrogate |
| int out = offset; |
| if (fSurrogate != -1) { |
| ch[offset + 1] = (char)fSurrogate; |
| fSurrogate = -1; |
| length--; |
| out++; |
| } |
| |
| // read bytes |
| int count = 0; |
| if (fOffset == 0) { |
| // adjust length to read |
| if (length > fBuffer.length) { |
| length = fBuffer.length; |
| } |
| |
| // perform read operation |
| count = fInputStream.read(fBuffer, 0, length); |
| if (count == -1) { |
| return -1; |
| } |
| count += out - offset; |
| } |
| |
| // skip read; last character was in error |
| // NOTE: Having an offset value other than zero means that there was |
| // an error in the last character read. In this case, we have |
| // skipped the read so we don't consume any bytes past the |
| // error. By signalling the error on the next block read we |
| // allow the method to return the most valid characters that |
| // it can on the previous block read. -Ac |
| else { |
| count = fOffset; |
| fOffset = 0; |
| } |
| |
| // convert bytes to characters |
| final int total = count; |
| for (int in = 0; in < total; in++) { |
| int b0 = fBuffer[in] & 0x00FF; |
| |
| // UTF-8: [0xxx xxxx] |
| // Unicode: [0000 0000] [0xxx xxxx] |
| if (b0 < 0x80) { |
| ch[out++] = (char)b0; |
| continue; |
| } |
| |
| // UTF-8: [110y yyyy] [10xx xxxx] |
| // Unicode: [0000 0yyy] [yyxx xxxx] |
| if ((b0 & 0xE0) == 0xC0) { |
| int b1 = -1; |
| if (++in < total) { |
| b1 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b1 = fInputStream.read(); |
| if (b1 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fOffset = 1; |
| return out - offset; |
| } |
| expectedByte(2, 2); |
| } |
| count++; |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fOffset = 2; |
| return out - offset; |
| } |
| invalidByte(2, 2, b1); |
| } |
| int c = ((b0 << 6) & 0x07C0) | (b1 & 0x003F); |
| ch[out++] = (char)c; |
| count -= 1; |
| continue; |
| } |
| |
| // UTF-8: [1110 zzzz] [10yy yyyy] [10xx xxxx] |
| // Unicode: [zzzz yyyy] [yyxx xxxx] |
| if ((b0 & 0xF0) == 0xE0) { |
| int b1 = -1; |
| if (++in < total) { |
| b1 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b1 = fInputStream.read(); |
| if (b1 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fOffset = 1; |
| return out - offset; |
| } |
| expectedByte(2, 3); |
| } |
| count++; |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fOffset = 2; |
| return out - offset; |
| } |
| invalidByte(2, 3, b1); |
| } |
| int b2 = -1; |
| if (++in < total) { |
| b2 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b2 = fInputStream.read(); |
| if (b2 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fOffset = 2; |
| return out - offset; |
| } |
| expectedByte(3, 3); |
| } |
| count++; |
| } |
| if ((b2 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fBuffer[2] = (byte)b2; |
| fOffset = 3; |
| return out - offset; |
| } |
| invalidByte(3, 3, b2); |
| } |
| int c = ((b0 << 12) & 0xF000) | ((b1 << 6) & 0x0FC0) | |
| (b2 & 0x003F); |
| ch[out++] = (char)c; |
| count -= 2; |
| continue; |
| } |
| |
| // UTF-8: [1111 0uuu] [10uu zzzz] [10yy yyyy] [10xx xxxx]* |
| // Unicode: [1101 10ww] [wwzz zzyy] (high surrogate) |
| // [1101 11yy] [yyxx xxxx] (low surrogate) |
| // * uuuuu = wwww + 1 |
| if ((b0 & 0xF8) == 0xF0) { |
| int b1 = -1; |
| if (++in < total) { |
| b1 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b1 = fInputStream.read(); |
| if (b1 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fOffset = 1; |
| return out - offset; |
| } |
| expectedByte(2, 4); |
| } |
| count++; |
| } |
| if ((b1 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fOffset = 2; |
| return out - offset; |
| } |
| invalidByte(2, 4, b1); |
| } |
| int b2 = -1; |
| if (++in < total) { |
| b2 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b2 = fInputStream.read(); |
| if (b2 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fOffset = 2; |
| return out - offset; |
| } |
| expectedByte(3, 4); |
| } |
| count++; |
| } |
| if ((b2 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fBuffer[2] = (byte)b2; |
| fOffset = 3; |
| return out - offset; |
| } |
| invalidByte(3, 4, b2); |
| } |
| int b3 = -1; |
| if (++in < total) { |
| b3 = fBuffer[in] & 0x00FF; |
| } |
| else { |
| b3 = fInputStream.read(); |
| if (b3 == -1) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fBuffer[2] = (byte)b2; |
| fOffset = 3; |
| return out - offset; |
| } |
| expectedByte(4, 4); |
| } |
| count++; |
| } |
| if ((b3 & 0xC0) != 0x80) { |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fBuffer[1] = (byte)b1; |
| fBuffer[2] = (byte)b2; |
| fBuffer[3] = (byte)b3; |
| fOffset = 4; |
| return out - offset; |
| } |
| invalidByte(4, 4, b2); |
| } |
| |
| // decode bytes into surrogate characters |
| int uuuuu = ((b0 << 2) & 0x001C) | ((b1 >> 4) & 0x0003); |
| if (uuuuu > 0x10) { |
| invalidSurrogate(uuuuu); |
| } |
| int wwww = uuuuu - 1; |
| int zzzz = b1 & 0x000F; |
| int yyyyyy = b2 & 0x003F; |
| int xxxxxx = b3 & 0x003F; |
| int hs = 0xD800 | ((wwww << 6) & 0x03C0) | (zzzz << 2) | (yyyyyy >> 4); |
| int ls = 0xDC00 | ((yyyyyy << 6) & 0x03C0) | xxxxxx; |
| |
| // set characters |
| ch[out++] = (char)hs; |
| ch[out++] = (char)ls; |
| count -= 2; |
| continue; |
| } |
| |
| // error |
| if (out > offset) { |
| fBuffer[0] = (byte)b0; |
| fOffset = 1; |
| return out - offset; |
| } |
| invalidByte(1, 1, b0); |
| } |
| |
| // return number of characters converted |
| if (DEBUG_READ) { |
| if (log.isDebugEnabled()) |
| log.debug("read(char[],"+offset+','+length+"): count="+count); |
| } |
| return count; |
| |
| } // read(char[],int,int) |
| |
| /** |
| * Skip characters. This method will block until some characters are |
| * available, an I/O error occurs, or the end of the stream is reached. |
| * |
| * @param n The number of characters to skip |
| * |
| * @return The number of characters actually skipped |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public long skip(long n) throws IOException { |
| |
| long remaining = n; |
| final char[] ch = new char[fBuffer.length]; |
| do { |
| int length = ch.length < remaining ? ch.length : (int)remaining; |
| int count = read(ch, 0, length); |
| if (count > 0) { |
| remaining -= count; |
| } |
| else { |
| break; |
| } |
| } while (remaining > 0); |
| |
| long skipped = n - remaining; |
| return skipped; |
| |
| } // skip(long):long |
| |
| /** |
| * Tell whether this stream is ready to be read. |
| * |
| * @return True if the next read() is guaranteed not to block for input, |
| * false otherwise. Note that returning false does not guarantee that the |
| * next read will block. |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public boolean ready() throws IOException { |
| return false; |
| } // ready() |
| |
| /** |
| * Tell whether this stream supports the mark() operation. |
| */ |
| public boolean markSupported() { |
| return false; |
| } // markSupported() |
| |
| /** |
| * Mark the present position in the stream. Subsequent calls to reset() |
| * will attempt to reposition the stream to this point. Not all |
| * character-input streams support the mark() operation. |
| * |
| * @param readAheadLimit Limit on the number of characters that may be |
| * read while still preserving the mark. After |
| * reading this many characters, attempting to |
| * reset the stream may fail. |
| * |
| * @exception IOException If the stream does not support mark(), |
| * or if some other I/O error occurs |
| */ |
| public void mark(int readAheadLimit) throws IOException { |
| throw new IOException( |
| Localizer.getMessage("jsp.error.xml.operationNotSupported", |
| "mark()", "UTF-8")); |
| } |
| |
| /** |
| * Reset the stream. If the stream has been marked, then attempt to |
| * reposition it at the mark. If the stream has not been marked, then |
| * attempt to reset it in some way appropriate to the particular stream, |
| * for example by repositioning it to its starting point. Not all |
| * character-input streams support the reset() operation, and some support |
| * reset() without supporting mark(). |
| * |
| * @exception IOException If the stream has not been marked, |
| * or if the mark has been invalidated, |
| * or if the stream does not support reset(), |
| * or if some other I/O error occurs |
| */ |
| public void reset() throws IOException { |
| fOffset = 0; |
| fSurrogate = -1; |
| } // reset() |
| |
| /** |
| * Close the stream. Once a stream has been closed, further read(), |
| * ready(), mark(), or reset() invocations will throw an IOException. |
| * Closing a previously-closed stream, however, has no effect. |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public void close() throws IOException { |
| fInputStream.close(); |
| } // close() |
| |
| // |
| // Private methods |
| // |
| |
| /** Throws an exception for expected byte. */ |
| private void expectedByte(int position, int count) |
| throws UTFDataFormatException { |
| |
| throw new UTFDataFormatException( |
| Localizer.getMessage("jsp.error.xml.expectedByte", |
| Integer.toString(position), |
| Integer.toString(count))); |
| |
| } // expectedByte(int,int,int) |
| |
| /** Throws an exception for invalid byte. */ |
| private void invalidByte(int position, int count, int c) |
| throws UTFDataFormatException { |
| |
| throw new UTFDataFormatException( |
| Localizer.getMessage("jsp.error.xml.invalidByte", |
| Integer.toString(position), |
| Integer.toString(count))); |
| } // invalidByte(int,int,int,int) |
| |
| /** Throws an exception for invalid surrogate bits. */ |
| private void invalidSurrogate(int uuuuu) throws UTFDataFormatException { |
| |
| throw new UTFDataFormatException( |
| Localizer.getMessage("jsp.error.xml.invalidHighSurrogate", |
| Integer.toHexString(uuuuu))); |
| } // invalidSurrogate(int) |
| |
| } // class UTF8Reader |
