--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/sun/net/www/http/ChunkedInputStream.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,771 @@
+/*
+ * Copyright 1999-2006 Sun Microsystems, Inc. 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package sun.net.www.http;
+
+import java.io.*;
+import java.util.*;
+
+import sun.net.*;
+import sun.net.www.*;
+
+/**
+ * A <code>ChunkedInputStream</code> provides a stream for reading a body of
+ * a http message that can be sent as a series of chunks, each with its own
+ * size indicator. Optionally the last chunk can be followed by trailers
+ * containing entity-header fields.
+ * <p>
+ * A <code>ChunkedInputStream</code> is also <code>Hurryable</code> so it
+ * can be hurried to the end of the stream if the bytes are available on
+ * the underlying stream.
+ */
+public
+class ChunkedInputStream extends InputStream implements Hurryable {
+
+ /**
+ * The underlying stream
+ */
+ private InputStream in;
+
+ /**
+ * The <code>HttpClient</code> that should be notified when the chunked stream has
+ * completed.
+ */
+ private HttpClient hc;
+
+ /**
+ * The <code>MessageHeader</code> that is populated with any optional trailer
+ * that appear after the last chunk.
+ */
+ private MessageHeader responses;
+
+ /**
+ * The size, in bytes, of the chunk that is currently being read.
+ * This size is only valid if the current position in the underlying
+ * input stream is inside a chunk (ie: state == STATE_READING_CHUNK).
+ */
+ private int chunkSize;
+
+ /**
+ * The number of bytes read from the underlying stream for the current
+ * chunk. This value is always in the range <code>0</code> through to
+ * <code>chunkSize</code>
+ */
+ private int chunkRead;
+
+ /**
+ * The internal buffer array where chunk data is available for the
+ * application to read.
+ */
+ private byte chunkData[] = new byte[4096];
+
+ /**
+ * The current position in the buffer. It contains the index
+ * of the next byte to read from <code>chunkData</code>
+ */
+ private int chunkPos;
+
+ /**
+ * The index one greater than the index of the last valid byte in the
+ * buffer. This value is always in the range <code>0</code> through
+ * <code>chunkData.length</code>.
+ */
+ private int chunkCount;
+
+ /**
+ * The internal buffer where bytes from the underlying stream can be
+ * read. It may contain bytes representing chunk-size, chunk-data, or
+ * trailer fields.
+ */
+ private byte rawData[] = new byte[32];
+
+ /**
+ * The current position in the buffer. It contains the index
+ * of the next byte to read from <code>rawData</code>
+ */
+ private int rawPos;
+
+ /**
+ * The index one greater than the index of the last valid byte in the
+ * buffer. This value is always in the range <code>0</code> through
+ * <code>rawData.length</code>.
+ */
+ private int rawCount;
+
+ /**
+ * Indicates if an error was encountered when processing the chunked
+ * stream.
+ */
+ private boolean error;
+
+ /**
+ * Indicates if the chunked stream has been closed using the
+ * <code>close</code> method.
+ */
+ private boolean closed;
+
+ /**
+ * State to indicate that next field should be :-
+ * chunk-size [ chunk-extension ] CRLF
+ */
+ static final int STATE_AWAITING_CHUNK_HEADER = 1;
+
+ /**
+ * State to indicate that we are currently reading the chunk-data.
+ */
+ static final int STATE_READING_CHUNK = 2;
+
+ /**
+ * Indicates that a chunk has been completely read and the next
+ * fields to be examine should be CRLF
+ */
+ static final int STATE_AWAITING_CHUNK_EOL = 3;
+
+ /**
+ * Indicates that all chunks have been read and the next field
+ * should be optional trailers or an indication that the chunked
+ * stream is complete.
+ */
+ static final int STATE_AWAITING_TRAILERS = 4;
+
+ /**
+ * State to indicate that the chunked stream is complete and
+ * no further bytes should be read from the underlying stream.
+ */
+ static final int STATE_DONE = 5;
+
+ /**
+ * Indicates the current state.
+ */
+ private int state;
+
+
+ /**
+ * Check to make sure that this stream has not been closed.
+ */
+ private void ensureOpen() throws IOException {
+ if (closed) {
+ throw new IOException("stream is closed");
+ }
+ }
+
+
+ /**
+ * Ensures there is <code>size</code> bytes available in
+ * <code>rawData</code>. This requires that we either
+ * shift the bytes in use to the begining of the buffer
+ * or allocate a large buffer with sufficient space available.
+ */
+ private void ensureRawAvailable(int size) {
+ if (rawCount + size > rawData.length) {
+ int used = rawCount - rawPos;
+ if (used + size > rawData.length) {
+ byte tmp[] = new byte[used + size];
+ if (used > 0) {
+ System.arraycopy(rawData, rawPos, tmp, 0, used);
+ }
+ rawData = tmp;
+ } else {
+ if (used > 0) {
+ System.arraycopy(rawData, rawPos, rawData, 0, used);
+ }
+ }
+ rawCount = used;
+ rawPos = 0;
+ }
+ }
+
+
+ /**
+ * Close the underlying input stream by either returning it to the
+ * keep alive cache or closing the stream.
+ * <p>
+ * As a chunked stream is inheritly persistent (see HTTP 1.1 RFC) the
+ * underlying stream can be returned to the keep alive cache if the
+ * stream can be completely read without error.
+ */
+ private void closeUnderlying() throws IOException {
+ if (in == null) {
+ return;
+ }
+
+ if (!error && state == STATE_DONE) {
+ hc.finished();
+ } else {
+ if (!hurry()) {
+ hc.closeServer();
+ }
+ }
+
+ in = null;
+ }
+
+ /**
+ * Attempt to read the remainder of a chunk directly into the
+ * caller's buffer.
+ * <p>
+ * Return the number of bytes read.
+ */
+ private int fastRead(byte[] b, int off, int len) throws IOException {
+
+ // assert state == STATE_READING_CHUNKS;
+
+ int remaining = chunkSize - chunkRead;
+ int cnt = (remaining < len) ? remaining : len;
+ if (cnt > 0) {
+ int nread;
+ try {
+ nread = in.read(b, off, cnt);
+ } catch (IOException e) {
+ error = true;
+ throw e;
+ }
+ if (nread > 0) {
+ chunkRead += nread;
+ if (chunkRead >= chunkSize) {
+ state = STATE_AWAITING_CHUNK_EOL;
+ }
+ return nread;
+ }
+ error = true;
+ throw new IOException("Premature EOF");
+ } else {
+ return 0;
+ }
+ }
+
+ /**
+ * Process any outstanding bytes that have already been read into
+ * <code>rawData</code>.
+ * <p>
+ * The parsing of the chunked stream is performed as a state machine with
+ * <code>state</code> representing the current state of the processing.
+ * <p>
+ * Returns when either all the outstanding bytes in rawData have been
+ * processed or there is insufficient bytes available to continue
+ * processing. When the latter occurs <code>rawPos</code> will not have
+ * been updated and thus the processing can be restarted once further
+ * bytes have been read into <code>rawData</code>.
+ */
+ private void processRaw() throws IOException {
+ int pos;
+ int i;
+
+ while (state != STATE_DONE) {
+
+ switch (state) {
+
+ /**
+ * We are awaiting a line with a chunk header
+ */
+ case STATE_AWAITING_CHUNK_HEADER:
+ /*
+ * Find \n to indicate end of chunk header. If not found when there is
+ * insufficient bytes in the raw buffer to parse a chunk header.
+ */
+ pos = rawPos;
+ while (pos < rawCount) {
+ if (rawData[pos] == '\n') {
+ break;
+ }
+ pos++;
+ }
+ if (pos >= rawCount) {
+ return;
+ }
+
+ /*
+ * Extract the chunk size from the header (ignoring extensions).
+ */
+ String header = new String(rawData, rawPos, pos-rawPos+1, "US-ASCII");
+ for (i=0; i < header.length(); i++) {
+ if (Character.digit(header.charAt(i), 16) == -1)
+ break;
+ }
+ try {
+ chunkSize = Integer.parseInt(header.substring(0, i), 16);
+ } catch (NumberFormatException e) {
+ error = true;
+ throw new IOException("Bogus chunk size");
+ }
+
+ /*
+ * Chunk has been parsed so move rawPos to first byte of chunk
+ * data.
+ */
+ rawPos = pos + 1;
+ chunkRead = 0;
+
+ /*
+ * A chunk size of 0 means EOF.
+ */
+ if (chunkSize > 0) {
+ state = STATE_READING_CHUNK;
+ } else {
+ state = STATE_AWAITING_TRAILERS;
+ }
+ break;
+
+
+ /**
+ * We are awaiting raw entity data (some may have already been
+ * read). chunkSize is the size of the chunk; chunkRead is the
+ * total read from the underlying stream to date.
+ */
+ case STATE_READING_CHUNK :
+ /* no data available yet */
+ if (rawPos >= rawCount) {
+ return;
+ }
+
+ /*
+ * Compute the number of bytes of chunk data available in the
+ * raw buffer.
+ */
+ int copyLen = Math.min( chunkSize-chunkRead, rawCount-rawPos );
+
+ /*
+ * Expand or compact chunkData if needed.
+ */
+ if (chunkData.length < chunkCount + copyLen) {
+ int cnt = chunkCount - chunkPos;
+ if (chunkData.length < cnt + copyLen) {
+ byte tmp[] = new byte[cnt + copyLen];
+ System.arraycopy(chunkData, chunkPos, tmp, 0, cnt);
+ chunkData = tmp;
+ } else {
+ System.arraycopy(chunkData, chunkPos, chunkData, 0, cnt);
+ }
+ chunkPos = 0;
+ chunkCount = cnt;
+ }
+
+ /*
+ * Copy the chunk data into chunkData so that it's available
+ * to the read methods.
+ */
+ System.arraycopy(rawData, rawPos, chunkData, chunkCount, copyLen);
+ rawPos += copyLen;
+ chunkCount += copyLen;
+ chunkRead += copyLen;
+
+ /*
+ * If all the chunk has been copied into chunkData then the next
+ * token should be CRLF.
+ */
+ if (chunkSize - chunkRead <= 0) {
+ state = STATE_AWAITING_CHUNK_EOL;
+ } else {
+ return;
+ }
+ break;
+
+
+ /**
+ * Awaiting CRLF after the chunk
+ */
+ case STATE_AWAITING_CHUNK_EOL:
+ /* not available yet */
+ if (rawPos + 1 >= rawCount) {
+ return;
+ }
+
+ if (rawData[rawPos] != '\r') {
+ error = true;
+ throw new IOException("missing CR");
+ }
+ if (rawData[rawPos+1] != '\n') {
+ error = true;
+ throw new IOException("missing LF");
+ }
+ rawPos += 2;
+
+ /*
+ * Move onto the next chunk
+ */
+ state = STATE_AWAITING_CHUNK_HEADER;
+ break;
+
+
+ /**
+ * Last chunk has been read so not we're waiting for optional
+ * trailers.
+ */
+ case STATE_AWAITING_TRAILERS:
+
+ /*
+ * Do we have an entire line in the raw buffer?
+ */
+ pos = rawPos;
+ while (pos < rawCount) {
+ if (rawData[pos] == '\n') {
+ break;
+ }
+ pos++;
+ }
+ if (pos >= rawCount) {
+ return;
+ }
+
+ if (pos == rawPos) {
+ error = true;
+ throw new IOException("LF should be proceeded by CR");
+ }
+ if (rawData[pos-1] != '\r') {
+ error = true;
+ throw new IOException("LF should be proceeded by CR");
+ }
+
+ /*
+ * Stream done so close underlying stream.
+ */
+ if (pos == (rawPos + 1)) {
+
+ state = STATE_DONE;
+ closeUnderlying();
+
+ return;
+ }
+
+ /*
+ * Extract any tailers and append them to the message
+ * headers.
+ */
+ String trailer = new String(rawData, rawPos, pos-rawPos, "US-ASCII");
+ i = trailer.indexOf(':');
+ if (i == -1) {
+ throw new IOException("Malformed tailer - format should be key:value");
+ }
+ String key = (trailer.substring(0, i)).trim();
+ String value = (trailer.substring(i+1, trailer.length())).trim();
+
+ responses.add(key, value);
+
+ /*
+ * Move onto the next trailer.
+ */
+ rawPos = pos+1;
+ break;
+
+ } /* switch */
+ }
+ }
+
+
+ /**
+ * Reads any available bytes from the underlying stream into
+ * <code>rawData</code> and returns the number of bytes of
+ * chunk data available in <code>chunkData</code> that the
+ * application can read.
+ */
+ private int readAheadNonBlocking() throws IOException {
+
+ /*
+ * If there's anything available on the underlying stream then we read
+ * it into the raw buffer and process it. Processing ensures that any
+ * available chunk data is made available in chunkData.
+ */
+ int avail = in.available();
+ if (avail > 0) {
+
+ /* ensure that there is space in rawData to read the available */
+ ensureRawAvailable(avail);
+
+ int nread;
+ try {
+ nread = in.read(rawData, rawCount, avail);
+ } catch (IOException e) {
+ error = true;
+ throw e;
+ }
+ if (nread < 0) {
+ error = true; /* premature EOF ? */
+ return -1;
+ }
+ rawCount += nread;
+
+ /*
+ * Process the raw bytes that have been read.
+ */
+ processRaw();
+ }
+
+ /*
+ * Return the number of chunked bytes available to read
+ */
+ return chunkCount - chunkPos;
+ }
+
+ /**
+ * Reads from the underlying stream until there is chunk data
+ * available in <code>chunkData</code> for the application to
+ * read.
+ */
+ private int readAheadBlocking() throws IOException {
+
+ do {
+ /*
+ * All of chunked response has been read to return EOF.
+ */
+ if (state == STATE_DONE) {
+ return -1;
+ }
+
+ /*
+ * We must read into the raw buffer so make sure there is space
+ * available. We use a size of 32 to avoid too much chunk data
+ * being read into the raw buffer.
+ */
+ ensureRawAvailable(32);
+ int nread;
+ try {
+ nread = in.read(rawData, rawCount, rawData.length-rawCount);
+ } catch (IOException e) {
+ error = true;
+ throw e;
+ }
+
+ /**
+ * If we hit EOF it means there's a problem as we should never
+ * attempt to read once the last chunk and trailers have been
+ * received.
+ */
+ if (nread < 0) {
+ error = true;
+ throw new IOException("Premature EOF");
+ }
+
+ /**
+ * Process the bytes from the underlying stream
+ */
+ rawCount += nread;
+ processRaw();
+
+ } while (chunkCount <= 0);
+
+ /*
+ * Return the number of chunked bytes available to read
+ */
+ return chunkCount - chunkPos;
+ }
+
+ /**
+ * Read ahead in either blocking or non-blocking mode. This method
+ * is typically used when we run out of available bytes in
+ * <code>chunkData</code> or we need to determine how many bytes
+ * are available on the input stream.
+ */
+ private int readAhead(boolean allowBlocking) throws IOException {
+
+ /*
+ * Last chunk already received - return EOF
+ */
+ if (state == STATE_DONE) {
+ return -1;
+ }
+
+ /*
+ * Reset position/count if data in chunkData is exhausted.
+ */
+ if (chunkPos >= chunkCount) {
+ chunkCount = 0;
+ chunkPos = 0;
+ }
+
+ /*
+ * Read ahead blocking or non-blocking
+ */
+ if (allowBlocking) {
+ return readAheadBlocking();
+ } else {
+ return readAheadNonBlocking();
+ }
+ }
+
+ /**
+ * Creates a <code>ChunkedInputStream</code> and saves its arguments, for
+ * later use.
+ *
+ * @param in the underlying input stream.
+ * @param hc the HttpClient
+ * @param responses the MessageHeader that should be populated with optional
+ * trailers.
+ */
+ public ChunkedInputStream(InputStream in, HttpClient hc, MessageHeader responses) throws IOException {
+
+ /* save arguments */
+ this.in = in;
+ this.responses = responses;
+ this.hc = hc;
+
+ /*
+ * Set our initial state to indicate that we are first starting to
+ * look for a chunk header.
+ */
+ state = STATE_AWAITING_CHUNK_HEADER;
+ }
+
+ /**
+ * See
+ * the general contract of the <code>read</code>
+ * method of <code>InputStream</code>.
+ *
+ * @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.
+ * @see java.io.FilterInputStream#in
+ */
+ public synchronized int read() throws IOException {
+ ensureOpen();
+ if (chunkPos >= chunkCount) {
+ if (readAhead(true) <= 0) {
+ return -1;
+ }
+ }
+ return chunkData[chunkPos++] & 0xff;
+ }
+
+
+ /**
+ * Reads bytes from this stream into the specified byte array, starting at
+ * the given offset.
+ *
+ * @param b destination buffer.
+ * @param off offset at which to start storing bytes.
+ * @param len maximum number of bytes to read.
+ * @return the number of bytes read, or <code>-1</code> if the end of
+ * the stream has been reached.
+ * @exception IOException if an I/O error occurs.
+ */
+ public synchronized int read(byte b[], int off, int len)
+ throws IOException
+ {
+ ensureOpen();
+ if ((off < 0) || (off > b.length) || (len < 0) ||
+ ((off + len) > b.length) || ((off + len) < 0)) {
+ throw new IndexOutOfBoundsException();
+ } else if (len == 0) {
+ return 0;
+ }
+
+ int avail = chunkCount - chunkPos;
+ if (avail <= 0) {
+ /*
+ * Optimization: if we're in the middle of the chunk read
+ * directly from the underlying stream into the caller's
+ * buffer
+ */
+ if (state == STATE_READING_CHUNK) {
+ return fastRead( b, off, len );
+ }
+
+ /*
+ * We're not in the middle of a chunk so we must read ahead
+ * until there is some chunk data available.
+ */
+ avail = readAhead(true);
+ if (avail < 0) {
+ return -1; /* EOF */
+ }
+ }
+ int cnt = (avail < len) ? avail : len;
+ System.arraycopy(chunkData, chunkPos, b, off, cnt);
+ chunkPos += cnt;
+
+ return cnt;
+ }
+
+ /**
+ * Returns the number of bytes that can be read from this input
+ * stream without blocking.
+ *
+ * @return the number of bytes that can be read from this input
+ * stream without blocking.
+ * @exception IOException if an I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public synchronized int available() throws IOException {
+ ensureOpen();
+
+ int avail = chunkCount - chunkPos;
+ if(avail > 0) {
+ return avail;
+ }
+
+ avail = readAhead(false);
+
+ if (avail < 0) {
+ return 0;
+ } else {
+ return avail;
+ }
+ }
+
+ /**
+ * Close the stream by either returning the connection to the
+ * keep alive cache or closing the underlying stream.
+ * <p>
+ * If the chunked response hasn't been completely read we
+ * try to "hurry" to the end of the response. If this is
+ * possible (without blocking) then the connection can be
+ * returned to the keep alive cache.
+ *
+ * @exception IOException if an I/O error occurs.
+ */
+ public synchronized void close() throws IOException {
+ if (closed) {
+ return;
+ }
+ closeUnderlying();
+ closed = true;
+ }
+
+ /**
+ * Hurry the input stream by reading everything from the underlying
+ * stream. If the last chunk (and optional trailers) can be read without
+ * blocking then the stream is considered hurried.
+ * <p>
+ * Note that if an error has occured or we can't get to last chunk
+ * without blocking then this stream can't be hurried and should be
+ * closed.
+ */
+ public synchronized boolean hurry() {
+ if (in == null || error) {
+ return false;
+ }
+
+ try {
+ readAhead(false);
+ } catch (Exception e) {
+ return false;
+ }
+
+ if (error) {
+ return false;
+ }
+
+ return (state == STATE_DONE);
+ }
+
+}