151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/* 251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Copyright (c) 1994, 2002, Oracle and/or its affiliates. All rights reserved. 351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is free software; you can redistribute it and/or modify it 651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * under the terms of the GNU General Public License version 2 only, as 751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * published by the Free Software Foundation. Oracle designates this 851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * particular file as subject to the "Classpath" exception as provided 951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * by Oracle in the LICENSE file that accompanied this code. 1051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is distributed in the hope that it will be useful, but WITHOUT 1251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * version 2 for more details (a copy is included in the LICENSE file that 1551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * accompanied this code). 1651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * You should have received a copy of the GNU General Public License version 1851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2 along with this work; if not, write to the Free Software Foundation, 1951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * or visit www.oracle.com if you need additional information or have any 2351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * questions. 2451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 2551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipackage sun.net; 2751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskiimport java.io.*; 2951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 3051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/** 3151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This class provides input and output streams for telnet clients. 3251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This class overrides write to do CRLF processing as specified in 3351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * RFC 854. The class assumes it is running on a system where lines 3451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * are terminated with a single newline <LF> character. 3551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 3651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This is the relevant section of RFC 824 regarding CRLF processing: 3751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 3851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <pre> 3951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The sequence "CR LF", as defined, will cause the NVT to be 4051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * positioned at the left margin of the next print line (as would, 4151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * for example, the sequence "LF CR"). However, many systems and 4251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * terminals do not treat CR and LF independently, and will have to 4351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * go to some effort to simulate their effect. (For example, some 4451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * terminals do not have a CR independent of the LF, but on such 4551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * terminals it may be possible to simulate a CR by backspacing.) 4651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Therefore, the sequence "CR LF" must be treated as a single "new 4751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * line" character and used whenever their combined action is 4851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * intended; the sequence "CR NUL" must be used where a carriage 4951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * return alone is actually desired; and the CR character must be 5051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * avoided in other contexts. This rule gives assurance to systems 5151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * which must decide whether to perform a "new line" function or a 5251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * multiple-backspace that the TELNET stream contains a character 5351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * following a CR that will allow a rational decision. 5451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 5551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Note that "CR LF" or "CR NUL" is required in both directions 5651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * (in the default ASCII mode), to preserve the symmetry of the 5751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * NVT model. Even though it may be known in some situations 5851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * (e.g., with remote echo and suppress go ahead options in 5951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * effect) that characters are not being sent to an actual 6051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * printer, nonetheless, for the sake of consistency, the protocol 6151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * requires that a NUL be inserted following a CR not followed by 6251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * a LF in the data stream. The converse of this is that a NUL 6351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * received in the data stream after a CR (in the absence of 6451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * options negotiations which explicitly specify otherwise) should 6551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * be stripped out prior to applying the NVT to local character 6651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * set mapping. 6751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * </pre> 6851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 6951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @author Jonathan Payne 7051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 7151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipublic class TelnetOutputStream extends BufferedOutputStream { 7351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski boolean stickyCRLF = false; 7451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski boolean seenCR = false; 7551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean binaryMode = false; 7751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public TelnetOutputStream(OutputStream fd, boolean binary) { 7951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super(fd); 8051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski binaryMode = binary; 8151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 8251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 8351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 8451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * set the stickyCRLF flag. Tells wether the terminal considers CRLF as a single 8551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * char. 8651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 8751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @param on the <code>boolean</code> to set the flag to. 8851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 8951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public void setStickyCRLF(boolean on) { 9051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski stickyCRLF = on; 9151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 9251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 9351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 9451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Writes the int to the stream and does CR LF processing if necessary. 9551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 9651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public void write(int c) throws IOException { 9751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (binaryMode) { 9851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write(c); 9951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return; 10051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 10151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 10251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (seenCR) { 10351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (c != '\n') 10451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write(0); 10551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write(c); 10651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (c != '\r') 10751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski seenCR = false; 10851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } else { // !seenCR 10951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (c == '\n') { 11051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write('\r'); 11151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write('\n'); 11251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return; 11351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 11451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (c == '\r') { 11551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (stickyCRLF) 11651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski seenCR = true; 11751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski else { 11851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write('\r'); 11951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski c = 0; 12051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 12151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 12251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write(c); 12351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 12451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 12551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 12651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 12751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Write the bytes at offset <i>off</i> in buffer <i>bytes</i> for 12851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <i>length</i> bytes. 12951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 13051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public void write(byte bytes[], int off, int length) throws IOException { 13151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (binaryMode) { 13251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski super.write(bytes, off, length); 13351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return; 13451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 13551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 13651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (--length >= 0) { 13751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski write(bytes[off++]); 13851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 13951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 14051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski} 141