internalinputbuffer.java

业界著名的tomcat服务器的最新6.0的源代码。

/*
 *  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.coyote.http11;

import java.io.IOException;
import java.io.InputStream;
import java.io.EOFException;

import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.buf.MessageBytes;
import org.apache.tomcat.util.http.MimeHeaders;
import org.apache.tomcat.util.res.StringManager;

import org.apache.coyote.InputBuffer;
import org.apache.coyote.Request;

/**
 * Implementation of InputBuffer which provides HTTP request header parsing as
 * well as transfer decoding.
 *
 * @author <a href="mailto:[e-mail]">Remy Maucherat</a>
 */
public class InternalInputBuffer implements InputBuffer {


    // -------------------------------------------------------------- Constants


    // ----------------------------------------------------------- Constructors


    /**
     * Default constructor.
     */
    public InternalInputBuffer(Request request) {
        this(request, Constants.DEFAULT_HTTP_HEADER_BUFFER_SIZE);
    }


    /**
     * Alternate constructor.
     */
    public InternalInputBuffer(Request request, int headerBufferSize) {

        this.request = request;
        headers = request.getMimeHeaders();

        buf = new byte[headerBufferSize];

        inputStreamInputBuffer = new InputStreamInputBuffer();

        filterLibrary = new InputFilter[0];
        activeFilters = new InputFilter[0];
        lastActiveFilter = -1;

        parsingHeader = true;
        swallowInput = true;

    }


    // -------------------------------------------------------------- Variables


    /**
     * The string manager for this package.
     */
    protected static StringManager sm =
        StringManager.getManager(Constants.Package);


    // ----------------------------------------------------- Instance Variables


    /**
     * Associated Coyote request.
     */
    protected Request request;


    /**
     * Headers of the associated request.
     */
    protected MimeHeaders headers;


    /**
     * State.
     */
    protected boolean parsingHeader;


    /**
     * Swallow input ? (in the case of an expectation)
     */
    protected boolean swallowInput;


    /**
     * Pointer to the current read buffer.
     */
    protected byte[] buf;


    /**
     * Last valid byte.
     */
    protected int lastValid;


    /**
     * Position in the buffer.
     */
    protected int pos;


    /**
     * Pos of the end of the header in the buffer, which is also the
     * start of the body.
     */
    protected int end;


    /**
     * Underlying input stream.
     */
    protected InputStream inputStream;


    /**
     * Underlying input buffer.
     */
    protected InputBuffer inputStreamInputBuffer;


    /**
     * Filter library.
     * Note: Filter[0] is always the "chunked" filter.
     */
    protected InputFilter[] filterLibrary;


    /**
     * Active filters (in order).
     */
    protected InputFilter[] activeFilters;


    /**
     * Index of the last active filter.
     */
    protected int lastActiveFilter;


    // ------------------------------------------------------------- Properties


    /**
     * Set the underlying socket input stream.
     */
    public void setInputStream(InputStream inputStream) {

        // FIXME: Check for null ?

        this.inputStream = inputStream;

    }


    /**
     * Get the underlying socket input stream.
     */
    public InputStream getInputStream() {

        return inputStream;

    }


    /**
     * Add an input filter to the filter library.
     */
    public void addFilter(InputFilter filter) {

        // FIXME: Check for null ?

        InputFilter[] newFilterLibrary = 
            new InputFilter[filterLibrary.length + 1];
        for (int i = 0; i < filterLibrary.length; i++) {
            newFilterLibrary[i] = filterLibrary[i];
        }
        newFilterLibrary[filterLibrary.length] = filter;
        filterLibrary = newFilterLibrary;

        activeFilters = new InputFilter[filterLibrary.length];

    }


    /**
     * Get filters.
     */
    public InputFilter[] getFilters() {

        return filterLibrary;

    }


    /**
     * Clear filters.
     */
    public void clearFilters() {

        filterLibrary = new InputFilter[0];
        lastActiveFilter = -1;

    }


    /**
     * Add an input filter to the filter library.
     */
    public void addActiveFilter(InputFilter filter) {

        if (lastActiveFilter == -1) {
            filter.setBuffer(inputStreamInputBuffer);
        } else {
            for (int i = 0; i <= lastActiveFilter; i++) {
                if (activeFilters[i] == filter)
                    return;
            }
            filter.setBuffer(activeFilters[lastActiveFilter]);
        }

        activeFilters[++lastActiveFilter] = filter;

        filter.setRequest(request);

    }


    /**
     * Set the swallow input flag.
     */
    public void setSwallowInput(boolean swallowInput) {
        this.swallowInput = swallowInput;
    }


    // --------------------------------------------------------- Public Methods


    /**
     * Recycle the input buffer. This should be called when closing the 
     * connection.
     */
    public void recycle() {

        // Recycle Request object
        request.recycle();

        inputStream = null;
        lastValid = 0;
        pos = 0;
        lastActiveFilter = -1;
        parsingHeader = true;
        swallowInput = true;

    }


    /**
     * End processing of current HTTP request.
     * Note: All bytes of the current request should have been already 
     * consumed. This method only resets all the pointers so that we are ready
     * to parse the next HTTP request.
     */
    public void nextRequest() {

        // Recycle Request object
        request.recycle();

        // Copy leftover bytes to the beginning of the buffer
        if (lastValid - pos > 0) {
            int npos = 0;
            int opos = pos;
            while (lastValid - opos > opos - npos) {
                System.arraycopy(buf, opos, buf, npos, opos - npos);
                npos += pos;
                opos += pos;
            }
            System.arraycopy(buf, opos, buf, npos, lastValid - opos);
        }

        // Recycle filters
        for (int i = 0; i <= lastActiveFilter; i++) {
            activeFilters[i].recycle();
        }

        // Reset pointers
        lastValid = lastValid - pos;
        pos = 0;
        lastActiveFilter = -1;
        parsingHeader = true;
        swallowInput = true;

    }


    /**
     * End request (consumes leftover bytes).
     * 
     * @throws IOException an undelying I/O error occured
     */
    public void endRequest()
        throws IOException {

        if (swallowInput && (lastActiveFilter != -1)) {
            int extraBytes = (int) activeFilters[lastActiveFilter].end();
            pos = pos - extraBytes;
        }

    }


    /**
     * Read the request line. This function is meant to be used during the 
     * HTTP request header parsing. Do NOT attempt to read the request body 
     * using it.
     *
     * @throws IOException If an exception occurs during the underlying socket
     * read operations, or if the given buffer is not big enough to accomodate
     * the whole line.
     */
    public void parseRequestLine()
        throws IOException {

        int start = 0;

        //
        // Skipping blank lines
        //

        byte chr = 0;
        do {

            // Read new bytes if needed
            if (pos >= lastValid) {
                if (!fill())
                    throw new EOFException(sm.getString("iib.eof.error"));
            }

            chr = buf[pos++];

        } while ((chr == Constants.CR) || (chr == Constants.LF));

        pos--;

        // Mark the current buffer position
        start = pos;

        //
        // Reading the method name
        // Method name is always US-ASCII
        //