/*

 * 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.

 *

 */

/**

 * @test

 * @bug 4507412

 * @bug 4506998

 * @summary Check that a 304 "Not-Modified" response from a server

 *          doesn't cause http client to close a keep-alive

 *          connection.

 *          Check that a content-length of 0 results in an

 *          empty input stream.

 */

import java.net.*;

import java.io.*;

public class ZeroContentLength {

    /*

     * Is debugging enabled - start with -d to enable.

     */

    static boolean debug = false;

    static void debug(String msg) {

        if (debug)

            System.out.println(msg);

    }

    /*

     * The response string and content-length that

     * the server should return;

     */

    static String response;

    static int contentLength;

    static synchronized void setResponse(String rsp, int cl) {

        response = rsp;

        contentLength = cl;

    }

    /*

     * Worker thread to service single connection - can service

     * multiple http requests on same connection.

     */

    class Worker extends Thread {

        Socket s;

        int id;

        Worker(Socket s, int id) {

            this.s = s;

            this.id = id;

        }

        public void run() {

            try {

                s.setSoTimeout(2000);

                int max = 100;

                for (;;) {

                    // read entire request from client

                    byte b[] = new byte[100];

                    InputStream in = s.getInputStream();

                    int n, total=0;

                    try {

                        do {

                            n = in.read(b);

                            if (n > 0) total += n;

                        } while (n > 0);

                    } catch (SocketTimeoutException e) { }

                    debug("worker " + id +

                        ": Read request from client " +

                        "(" + total + " bytes).");

                    if (total == 0) {

                        debug("worker: " + id + ": Shutdown");

                        return;

                    }

                    // response to client

                    PrintStream out = new PrintStream(

                                        new BufferedOutputStream(

                                                s.getOutputStream() ));

                    out.print("HTTP/1.1 " + response + "\r\n");

                    if (contentLength >= 0) {

                        out.print("Content-Length: " + contentLength +

                                    "\r\n");

                    }

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

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

                        out.write( (byte)'.' );

                    }

                    out.flush();

                    debug("worked " + id +

                        ": Sent response to client, length: " + contentLength);

                    if (--max == 0) {

                        s.close();

                        return;

                    }

                }

            } catch (Exception e) {

                e.printStackTrace();

            } finally {

                try {

                    s.close();

                } catch (Exception e) { }

            }

        }

    }

    /*

     * Server thread to accept connection and create worker threads

     * to service each connection.

     */

    class Server extends Thread {

        ServerSocket ss;

        int connectionCount;

        boolean shutdown = false;

        Server(ServerSocket ss) {

            this.ss = ss;

        }

        public synchronized int connectionCount() {

            return connectionCount;

        }

        public synchronized void shutdown() {

            shutdown = true;

        }

        public void run() {

            try {

                ss.setSoTimeout(2000);

                for (;;) {

                    Socket s;

                    try {

                        debug("server: Waiting for connections");

                        s = ss.accept();

                    } catch (SocketTimeoutException te) {

                        synchronized (this) {

                            if (shutdown) {

                                debug("server: Shuting down.");

                                return;

                            }

                        }

                        continue;

                    }

                    int id;

                    synchronized (this) {

                        id = connectionCount++;

                    }

                    Worker w = new Worker(s, id);

                    w.start();

                    debug("server: Started worker " + id);

                }

            } catch (Exception e) {

                e.printStackTrace();

            } finally {

                try {

                    ss.close();

                } catch (Exception e) { }

            }

        }

    }

    /*

     * Make a single http request and return the content length

     * received. Also do sanity check to ensure that the

     * content-length header matches the total received on

     * the input stream.

     */

    int doRequest(String uri) throws Exception {

        URL url = new URL(uri);

        HttpURLConnection http = (HttpURLConnection)url.openConnection();

        int cl = http.getContentLength();

        InputStream in = http.getInputStream();

        byte b[] = new byte[100];

        int total = 0;

        int n;

        do {

            n = in.read(b);

            if (n > 0) total += n;

        } while (n > 0);

        in.close();

        if (cl >= 0 && total != cl) {

            System.err.println("content-length header indicated: " + cl);

            System.err.println("Actual received: " + total);

            throw new Exception("Content-length didn't match actual received");

        }

        return total;

    }

    /*

     * Send http requests to "server" and check that they all

     * use the same network connection and that the content

     * length corresponds to the content length expected.

     * stream.

     */

    ZeroContentLength() throws Exception {

        /* start the server */

        ServerSocket ss = new ServerSocket(0);

        Server svr = new Server(ss);

        svr.start();

        String uri = "http://localhost:" +

                     Integer.toString(ss.getLocalPort()) +

                     "/foo.html";

        int expectedTotal = 0;

        int actualTotal = 0;

        System.out.println("**********************************");

        System.out.println("200 OK, content-length:1024 ...");

        setResponse("200 OK", 1024);

        for (int i=0; i<5; i++) {

            actualTotal += doRequest(uri);

            expectedTotal += 1024;

        }

        System.out.println("**********************************");

        System.out.println("200 OK, content-length:0 ...");

        setResponse("200 OK", 0);

        for (int i=0; i<5; i++) {

            actualTotal += doRequest(uri);

        }

        System.out.println("**********************************");

        System.out.println("304 Not-Modified, (no content-length) ...");

        setResponse("304 Not-Modifed", -1);

        for (int i=0; i<5; i++) {

            actualTotal += doRequest(uri);

        }

        System.out.println("**********************************");

        System.out.println("204 No-Content, (no content-length) ...");

        setResponse("204 No-Content", -1);

        for (int i=0; i<5; i++) {

            actualTotal += doRequest(uri);

        }

        // shutdown server - we're done.

        svr.shutdown();

        System.out.println("**********************************");

        if (actualTotal == expectedTotal) {

            System.out.println("Passed: Actual total equal to expected total");

        } else {

            throw new Exception("Actual total != Expected total!!!");

        }

        int cnt = svr.connectionCount();

        if (cnt == 1) {

            System.out.println("Passed: Only 1 connection established");

        } else {

            throw new Exception("Test failed: Number of connections " +

                "established: " + cnt + " - see log for details.");

        }

    }

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

        if (args.length > 0 && args[0].equals("-d")) {

            debug = true;

        }

        new ZeroContentLength();

    }

}