/*

 * Copyright (c) 2002, 2019, Oracle and/or its affiliates. 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.

 *

 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/**

 * @test

 * @bug 4774503

 * @library /test/lib

 * @summary Calling HttpURLConnection's disconnect method after the

 *          response has been received causes havoc with persistent

 *          connections.

 */

import java.net.*;

import java.io.*;

import java.util.*;

import jdk.test.lib.net.URIBuilder;

public class DisconnectAfterEOF {

    /*

     * Worker thread to service single connection - can service

     * multiple http requests on same connection.

     */

    static class Worker extends Thread {

        Socket s;

        Worker(Socket s) {

            this.s = s;

        }

        public void run() {

            try {

                InputStream in = s.getInputStream();

                PrintStream out = new PrintStream(

                                        new BufferedOutputStream(

                                                s.getOutputStream() ));

                byte b[] = new byte[1024];

                int n = -1;

                int cl = -1;

                int remaining = -1;

                StringBuffer sb = new StringBuffer();

                boolean close = false;

                boolean inBody = false;

                for (;;) {

                    boolean sendResponse = false;

                    try {

                        n = in.read(b);

                    } catch (IOException ioe) {

                        n = -1;

                    }

                    if (n <= 0) {

                        if (inBody) {

                            System.err.println("ERROR: Client closed before before " +

                                "entire request received.");

                        }

                        return;

                    }

                    // reading entity-body

                    if (inBody) {

                        if (n > remaining) {

                            System.err.println("Receiving more than expected!!!");

                            return;

                        }

                        remaining -= n;

                        if (remaining == 0) {

                            sendResponse = true;

                            n = 0;

                        } else {

                            continue;

                        }

                    }

                    // reading headers

                    for (int i=0; i<n; i++) {

                        char c = (char)b[i];

                        if (c != '\n') {

                            sb.append(c);

                            continue;

                        }

                        // Got end-of-line

                        int len = sb.length();

                        if (len > 0) {

                            if (sb.charAt(len-1) != '\r') {

                                System.err.println("Unexpected CR in header!!");

                                return;

                            }

                        }

                        sb.setLength(len-1);

                        // empty line

                        if (sb.length() == 0) {

                            if (cl < 0) {

                                System.err.println("Content-Length not found!!!");

                                return;

                            }

                            // the surplus is body data

                            int dataRead = n - (i+1);

                            remaining = cl - dataRead;

                            if (remaining > 0) {

                                inBody = true;

                                break;

                            } else {

                                // entire body has been read

                                sendResponse = true;

                            }

                        } else {

                            // non-empty line - check for Content-Length

                            String line = sb.toString().toLowerCase();

                            if (line.startsWith("content-length")) {

                                StringTokenizer st = new StringTokenizer(line, ":");

                                st.nextToken();

                                cl = Integer.parseInt(st.nextToken().trim());

                            }

                            if (line.startsWith("connection")) {

                                StringTokenizer st = new StringTokenizer(line, ":");

                                st.nextToken();

                                if (st.nextToken().trim().equals("close")) {

                                    close =true;

                                }

                            }

                        }

                        sb = new StringBuffer();

                    }

                   if (sendResponse) {

                        // send a large response

                        int rspLen = 32000;

                        out.print("HTTP/1.1 200 OK\r\n");

                        out.print("Content-Length: " + rspLen + "\r\n");

                        out.print("\r\n");

                        if (rspLen > 0)

                            out.write(new byte[rspLen]);

                        out.flush();

                        if (close)

                            return;

                        sendResponse = false;

                        inBody = false;

                        cl = -1;

                   }

                }

            } catch (IOException ioe) {

            } finally {

                try {

                    s.close();

                } catch (Exception e) { }

                System.out.println("+ Worker thread shutdown.");

            }

        }

    }

    /*

     * Server thread to accept connection and create worker threads

     * to service each connection.

     */

    static class Server extends Thread {

        ServerSocket ss;

        Server(ServerSocket ss) {

            this.ss = ss;

        }

        public void run() {

            try {

                for (;;) {

                    Socket s = ss.accept();

                    Worker w = new Worker(s);

                    w.start();

                }

            } catch (IOException ioe) {

            }

            System.out.println("+ Server shutdown.");

        }

        public void shutdown() {

            try {

                ss.close();

            } catch (IOException ioe) { }

        }

    }

    static URLConnection doRequest(String uri) throws IOException {

        uc.setDoOutput(true);

        OutputStream out = uc.getOutputStream();

        out.write(new byte[16000]);

        // force the request to be sent

        uc.getInputStream();

        return uc;

    }

    static URLConnection doResponse(URLConnection uc) throws IOException {

        int cl = ((HttpURLConnection)uc).getContentLength();

        byte b[] = new byte[4096];

        int n;

        do {

            n = uc.getInputStream().read(b);

            if (n > 0) cl -= n;

        } while (n > 0);

        if (cl != 0) {

            throw new RuntimeException("ERROR: content-length mismatch");

        }

        return uc;

    }

    public static void main(String args[]) throws Exception {

        // start server

        InetAddress loopback = InetAddress.getLoopbackAddress();

        ServerSocket ss = new ServerSocket();

        ss.bind(new InetSocketAddress(loopback, 0));

        Server svr = new Server(ss);

        svr.start();

        String uri = URIBuilder.newBuilder()

                     .scheme("http")

                     .loopback()

                     .port(ss.getLocalPort())

                     .path("/foo.html")

                     .build().toString();

        /*

         * The following is the test scenario we create here :-

         *

         * 1. We do a http request/response and read the response

         *    to EOF. As it's a persistent connection the idle

         *    connection should go into the keep-alive cache for a

         *    few seconds.

         *

         * 2. We start a second request but don't read the response.

         *    As the request is to the same server we can assume it

         *    (for our implementation anyway) that it will use the

         *    same TCP connection.

         *

         * 3. We "disconnect" the first HttpURLConnection. This

         *    should be no-op because the connection is in use

         *    but another request. However with 1.3.1 and 1.4/1.4.1

         *    this causes the TCP connection for the second request

         *    to be closed.

         *

         */

        URLConnection uc1 = doRequest(uri);

        doResponse(uc1);

        Thread.sleep(2000);

        URLConnection uc2 = doRequest(uri);

        ((HttpURLConnection)uc1).disconnect();

        IOException ioe = null;

        try {

            doResponse(uc2);

        } catch (IOException x) {

            ioe = x;

        }

        ((HttpURLConnection)uc2).disconnect();

        /*

         * Shutdown server as we are done. Worker threads created

         * by the server will shutdown automatically when the

         * client connection closes.

         */

        svr.shutdown();

        if (ioe != null) {

            throw ioe;

        }

    }

}