diff options
Diffstat (limited to 'libjava/classpath/java/util/zip/Inflater.java')
| -rw-r--r-- | libjava/classpath/java/util/zip/Inflater.java | 438 |
1 files changed, 219 insertions, 219 deletions
diff --git a/libjava/classpath/java/util/zip/Inflater.java b/libjava/classpath/java/util/zip/Inflater.java index f529dc691c6..0f094d66744 100644 --- a/libjava/classpath/java/util/zip/Inflater.java +++ b/libjava/classpath/java/util/zip/Inflater.java @@ -7,7 +7,7 @@ GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. - + GNU Classpath 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 @@ -43,7 +43,7 @@ package java.util.zip; */ /** - * Inflater is used to decompress data that has been compressed according + * Inflater is used to decompress data that has been compressed according * to the "deflate" standard described in rfc1950. * * The usage is as following. First you have to set some input with @@ -51,10 +51,10 @@ package java.util.zip; * inflate any bytes there may be three reasons: * <ul> * <li>needsInput() returns true because the input buffer is empty. - * You have to provide more input with <code>setInput()</code>. + * You have to provide more input with <code>setInput()</code>. * NOTE: needsInput() also returns true when, the stream is finished. * </li> - * <li>needsDictionary() returns true, you have to provide a preset + * <li>needsDictionary() returns true, you have to provide a preset * dictionary with <code>setDictionary()</code>.</li> * <li>finished() returns true, the inflater has finished.</li> * </ul> @@ -69,15 +69,15 @@ package java.util.zip; public class Inflater { /* Copy lengths for literal codes 257..285 */ - private static final int CPLENS[] = - { + private static final int CPLENS[] = + { 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258 }; - - /* Extra bits for literal codes 257..285 */ - private static final int CPLEXT[] = - { + + /* Extra bits for literal codes 257..285 */ + private static final int CPLEXT[] = + { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0 }; @@ -88,11 +88,11 @@ public class Inflater 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577 }; - + /* Extra bits for distance codes */ private static final int CPDEXT[] = { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, - 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, + 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13 }; @@ -122,10 +122,10 @@ public class Inflater * Only valid if mode is DECODE_DICT or DECODE_CHKSUM. */ private int readAdler; - /** + /** * The number of bits needed to complete the current state. This * is valid, if mode is DECODE_DICT, DECODE_CHKSUM, - * DECODE_HUFFMAN_LENBITS or DECODE_HUFFMAN_DISTBITS. + * DECODE_HUFFMAN_LENBITS or DECODE_HUFFMAN_DISTBITS. */ private int neededBits; private int repLength, repDist; @@ -133,7 +133,7 @@ public class Inflater /** * True, if the last block flag was set in the last block of the * inflated stream. This means that the stream ends after the - * current block. + * current block. */ private boolean isLastBlock; @@ -143,7 +143,7 @@ public class Inflater private long totalOut; /** * The total number of bytes set with setInput(). This is not the - * value returned by getTotalIn(), since this also includes the + * value returned by getTotalIn(), since this also includes the * unprocessed input. */ private long totalIn; @@ -198,7 +198,7 @@ public class Inflater * for the Sun implementation). Exists only for compatibility * with Sun's JDK, where the compressor allocates native memory. * If you call any method (even reset) afterwards the behaviour is - * <i>undefined</i>. + * <i>undefined</i>. */ public void end () { @@ -214,7 +214,7 @@ public class Inflater * Returns true, if the inflater has finished. This means, that no * input is needed and no output can be produced. */ - public boolean finished() + public boolean finished() { return mode == FINISHED && outputWindow.getAvailable() == 0; } @@ -230,18 +230,18 @@ public class Inflater { return needsDictionary() ? readAdler : (int) adler.getValue(); } - + /** * Gets the number of unprocessed input. Useful, if the end of the * stream is reached and you want to further process the bytes after - * the deflate stream. + * the deflate stream. * @return the number of bytes of the input which were not processed. */ public int getRemaining() { return input.getAvailableBytes(); } - + /** * Gets the total number of processed compressed input bytes. * @return the total number of bytes of processed input bytes. @@ -283,11 +283,11 @@ public class Inflater /** * Inflates the compressed stream to the output buffer. If this * returns 0, you should check, whether needsDictionary(), - * needsInput() or finished() returns true, to determine why no + * needsInput() or finished() returns true, to determine why no * further output is produced. * @param buf the output buffer. * @return the number of bytes written to the buffer, 0 if no further - * output can be produced. + * output can be produced. * @exception DataFormatException if deflated stream is invalid. * @exception IllegalArgumentException if buf has length 0. */ @@ -299,13 +299,13 @@ public class Inflater /** * Inflates the compressed stream to the output buffer. If this * returns 0, you should check, whether needsDictionary(), - * needsInput() or finished() returns true, to determine why no + * needsInput() or finished() returns true, to determine why no * further output is produced. * @param buf the output buffer. * @param off the offset into buffer where the output should start. * @param len the maximum length of the output. * @return the number of bytes written to the buffer, 0 if no further - * output can be produced. + * output can be produced. * @exception DataFormatException if deflated stream is invalid. * @exception IndexOutOfBoundsException if the off and/or len are wrong. */ @@ -351,7 +351,7 @@ public class Inflater * * <em>NOTE</em>: This method also returns true when the stream is finished. */ - public boolean needsInput () + public boolean needsInput () { return input.needsInput (); } @@ -381,7 +381,7 @@ public class Inflater * @param buffer the dictionary. * @exception IllegalStateException if no dictionary is needed. * @exception IllegalArgumentException if the dictionary checksum is - * wrong. + * wrong. */ public void setDictionary (byte[] buffer) { @@ -398,7 +398,7 @@ public class Inflater * @param len the length of the dictionary. * @exception IllegalStateException if no dictionary is needed. * @exception IllegalArgumentException if the dictionary checksum is - * wrong. + * wrong. * @exception IndexOutOfBoundsException if the off and/or len are wrong. */ public void setDictionary (byte[] buffer, int off, int len) @@ -420,7 +420,7 @@ public class Inflater * @param buf the input. * @exception IllegalStateException if no input is needed. */ - public void setInput (byte[] buf) + public void setInput (byte[] buf) { setInput (buf, 0, buf.length); } @@ -430,11 +430,11 @@ public class Inflater * returns true. * @param buf the input. * @param off the offset into buffer where the input starts. - * @param len the length of the input. + * @param len the length of the input. * @exception IllegalStateException if no input is needed. * @exception IndexOutOfBoundsException if the off and/or len are wrong. */ - public void setInput (byte[] buf, int off, int len) + public void setInput (byte[] buf, int off, int len) { input.setInput (buf, off, len); totalIn += len; @@ -442,7 +442,7 @@ public class Inflater /** * Decodes the deflate header. - * @return false if more input is needed. + * @return false if more input is needed. * @exception DataFormatException if header is invalid. */ private boolean decodeHeader () throws DataFormatException @@ -451,48 +451,48 @@ public class Inflater if (header < 0) return false; input.dropBits(16); - + /* The header is written in "wrong" byte order */ header = ((header << 8) | (header >> 8)) & 0xffff; if (header % 31 != 0) throw new DataFormatException("Header checksum illegal"); - + if ((header & 0x0f00) != (Deflater.DEFLATED << 8)) throw new DataFormatException("Compression Method unknown"); - /* Maximum size of the backwards window in bits. + /* Maximum size of the backwards window in bits. * We currently ignore this, but we could use it to make the * inflater window more space efficient. On the other hand the * full window (15 bits) is needed most times, anyway. int max_wbits = ((header & 0x7000) >> 12) + 8; */ - + if ((header & 0x0020) == 0) // Dictionary flag? { - mode = DECODE_BLOCKS; + mode = DECODE_BLOCKS; } else { - mode = DECODE_DICT; - neededBits = 32; + mode = DECODE_DICT; + neededBits = 32; } return true; } - + /** * Decodes the dictionary checksum after the deflate header. - * @return false if more input is needed. + * @return false if more input is needed. */ private boolean decodeDict () { while (neededBits > 0) { - int dictByte = input.peekBits(8); - if (dictByte < 0) - return false; - input.dropBits(8); - readAdler = (readAdler << 8) | dictByte; - neededBits -= 8; + int dictByte = input.peekBits(8); + if (dictByte < 0) + return false; + input.dropBits(8); + readAdler = (readAdler << 8) | dictByte; + neededBits -= 8; } return false; } @@ -501,226 +501,226 @@ public class Inflater * Decodes the huffman encoded symbols in the input stream. * @return false if more input is needed, true if output window is * full or the current block ends. - * @exception DataFormatException if deflated stream is invalid. + * @exception DataFormatException if deflated stream is invalid. */ private boolean decodeHuffman () throws DataFormatException { int free = outputWindow.getFreeSpace(); while (free >= 258) { - int symbol; - switch (mode) - { - case DECODE_HUFFMAN: - /* This is the inner loop so it is optimized a bit */ - while (((symbol = litlenTree.getSymbol(input)) & ~0xff) == 0) - { - outputWindow.write(symbol); - if (--free < 258) - return true; - } - if (symbol < 257) - { - if (symbol < 0) - return false; - else - { - /* symbol == 256: end of block */ - distTree = null; - litlenTree = null; - mode = DECODE_BLOCKS; - return true; - } - } - - try - { - repLength = CPLENS[symbol - 257]; - neededBits = CPLEXT[symbol - 257]; - } - catch (ArrayIndexOutOfBoundsException ex) - { - throw new DataFormatException("Illegal rep length code"); - } - /* fall through */ - case DECODE_HUFFMAN_LENBITS: - if (neededBits > 0) - { - mode = DECODE_HUFFMAN_LENBITS; - int i = input.peekBits(neededBits); - if (i < 0) - return false; - input.dropBits(neededBits); - repLength += i; - } - mode = DECODE_HUFFMAN_DIST; - /* fall through */ - case DECODE_HUFFMAN_DIST: - symbol = distTree.getSymbol(input); - if (symbol < 0) - return false; - try - { - repDist = CPDIST[symbol]; - neededBits = CPDEXT[symbol]; - } - catch (ArrayIndexOutOfBoundsException ex) - { - throw new DataFormatException("Illegal rep dist code"); - } - /* fall through */ - case DECODE_HUFFMAN_DISTBITS: - if (neededBits > 0) - { - mode = DECODE_HUFFMAN_DISTBITS; - int i = input.peekBits(neededBits); - if (i < 0) - return false; - input.dropBits(neededBits); - repDist += i; - } - outputWindow.repeat(repLength, repDist); - free -= repLength; - mode = DECODE_HUFFMAN; - break; - default: - throw new IllegalStateException(); - } + int symbol; + switch (mode) + { + case DECODE_HUFFMAN: + /* This is the inner loop so it is optimized a bit */ + while (((symbol = litlenTree.getSymbol(input)) & ~0xff) == 0) + { + outputWindow.write(symbol); + if (--free < 258) + return true; + } + if (symbol < 257) + { + if (symbol < 0) + return false; + else + { + /* symbol == 256: end of block */ + distTree = null; + litlenTree = null; + mode = DECODE_BLOCKS; + return true; + } + } + + try + { + repLength = CPLENS[symbol - 257]; + neededBits = CPLEXT[symbol - 257]; + } + catch (ArrayIndexOutOfBoundsException ex) + { + throw new DataFormatException("Illegal rep length code"); + } + /* fall through */ + case DECODE_HUFFMAN_LENBITS: + if (neededBits > 0) + { + mode = DECODE_HUFFMAN_LENBITS; + int i = input.peekBits(neededBits); + if (i < 0) + return false; + input.dropBits(neededBits); + repLength += i; + } + mode = DECODE_HUFFMAN_DIST; + /* fall through */ + case DECODE_HUFFMAN_DIST: + symbol = distTree.getSymbol(input); + if (symbol < 0) + return false; + try + { + repDist = CPDIST[symbol]; + neededBits = CPDEXT[symbol]; + } + catch (ArrayIndexOutOfBoundsException ex) + { + throw new DataFormatException("Illegal rep dist code"); + } + /* fall through */ + case DECODE_HUFFMAN_DISTBITS: + if (neededBits > 0) + { + mode = DECODE_HUFFMAN_DISTBITS; + int i = input.peekBits(neededBits); + if (i < 0) + return false; + input.dropBits(neededBits); + repDist += i; + } + outputWindow.repeat(repLength, repDist); + free -= repLength; + mode = DECODE_HUFFMAN; + break; + default: + throw new IllegalStateException(); + } } return true; } /** * Decodes the adler checksum after the deflate stream. - * @return false if more input is needed. + * @return false if more input is needed. * @exception DataFormatException if checksum doesn't match. */ private boolean decodeChksum () throws DataFormatException { while (neededBits > 0) { - int chkByte = input.peekBits(8); - if (chkByte < 0) - return false; - input.dropBits(8); - readAdler = (readAdler << 8) | chkByte; - neededBits -= 8; + int chkByte = input.peekBits(8); + if (chkByte < 0) + return false; + input.dropBits(8); + readAdler = (readAdler << 8) | chkByte; + neededBits -= 8; } if ((int) adler.getValue() != readAdler) throw new DataFormatException("Adler chksum doesn't match: " - +Integer.toHexString((int)adler.getValue()) - +" vs. "+Integer.toHexString(readAdler)); + +Integer.toHexString((int)adler.getValue()) + +" vs. "+Integer.toHexString(readAdler)); mode = FINISHED; return false; } /** * Decodes the deflated stream. - * @return false if more input is needed, or if finished. + * @return false if more input is needed, or if finished. * @exception DataFormatException if deflated stream is invalid. */ private boolean decode () throws DataFormatException { - switch (mode) + switch (mode) { case DECODE_HEADER: - return decodeHeader(); + return decodeHeader(); case DECODE_DICT: - return decodeDict(); + return decodeDict(); case DECODE_CHKSUM: - return decodeChksum(); + return decodeChksum(); case DECODE_BLOCKS: - if (isLastBlock) - { - if (nowrap) - { - mode = FINISHED; - return false; - } - else - { - input.skipToByteBoundary(); - neededBits = 32; - mode = DECODE_CHKSUM; - return true; - } - } - - int type = input.peekBits(3); - if (type < 0) - return false; - input.dropBits(3); - - if ((type & 1) != 0) - isLastBlock = true; - switch (type >> 1) - { - case DeflaterConstants.STORED_BLOCK: - input.skipToByteBoundary(); - mode = DECODE_STORED_LEN1; - break; - case DeflaterConstants.STATIC_TREES: - litlenTree = InflaterHuffmanTree.defLitLenTree; - distTree = InflaterHuffmanTree.defDistTree; - mode = DECODE_HUFFMAN; - break; - case DeflaterConstants.DYN_TREES: - dynHeader = new InflaterDynHeader(); - mode = DECODE_DYN_HEADER; - break; - default: - throw new DataFormatException("Unknown block type "+type); - } - return true; + if (isLastBlock) + { + if (nowrap) + { + mode = FINISHED; + return false; + } + else + { + input.skipToByteBoundary(); + neededBits = 32; + mode = DECODE_CHKSUM; + return true; + } + } + + int type = input.peekBits(3); + if (type < 0) + return false; + input.dropBits(3); + + if ((type & 1) != 0) + isLastBlock = true; + switch (type >> 1) + { + case DeflaterConstants.STORED_BLOCK: + input.skipToByteBoundary(); + mode = DECODE_STORED_LEN1; + break; + case DeflaterConstants.STATIC_TREES: + litlenTree = InflaterHuffmanTree.defLitLenTree; + distTree = InflaterHuffmanTree.defDistTree; + mode = DECODE_HUFFMAN; + break; + case DeflaterConstants.DYN_TREES: + dynHeader = new InflaterDynHeader(); + mode = DECODE_DYN_HEADER; + break; + default: + throw new DataFormatException("Unknown block type "+type); + } + return true; case DECODE_STORED_LEN1: - { - if ((uncomprLen = input.peekBits(16)) < 0) - return false; - input.dropBits(16); - mode = DECODE_STORED_LEN2; - } - /* fall through */ + { + if ((uncomprLen = input.peekBits(16)) < 0) + return false; + input.dropBits(16); + mode = DECODE_STORED_LEN2; + } + /* fall through */ case DECODE_STORED_LEN2: - { - int nlen = input.peekBits(16); - if (nlen < 0) - return false; - input.dropBits(16); - if (nlen != (uncomprLen ^ 0xffff)) - throw new DataFormatException("broken uncompressed block"); - mode = DECODE_STORED; - } - /* fall through */ + { + int nlen = input.peekBits(16); + if (nlen < 0) + return false; + input.dropBits(16); + if (nlen != (uncomprLen ^ 0xffff)) + throw new DataFormatException("broken uncompressed block"); + mode = DECODE_STORED; + } + /* fall through */ case DECODE_STORED: - { - int more = outputWindow.copyStored(input, uncomprLen); - uncomprLen -= more; - if (uncomprLen == 0) - { - mode = DECODE_BLOCKS; - return true; - } - return !input.needsInput(); - } + { + int more = outputWindow.copyStored(input, uncomprLen); + uncomprLen -= more; + if (uncomprLen == 0) + { + mode = DECODE_BLOCKS; + return true; + } + return !input.needsInput(); + } case DECODE_DYN_HEADER: - if (!dynHeader.decode(input)) - return false; - litlenTree = dynHeader.buildLitLenTree(); - distTree = dynHeader.buildDistTree(); - mode = DECODE_HUFFMAN; - /* fall through */ + if (!dynHeader.decode(input)) + return false; + litlenTree = dynHeader.buildLitLenTree(); + distTree = dynHeader.buildDistTree(); + mode = DECODE_HUFFMAN; + /* fall through */ case DECODE_HUFFMAN: case DECODE_HUFFMAN_LENBITS: case DECODE_HUFFMAN_DIST: case DECODE_HUFFMAN_DISTBITS: - return decodeHuffman(); + return decodeHuffman(); case FINISHED: - return false; + return false; default: - throw new IllegalStateException(); - } + throw new IllegalStateException(); + } } } |
