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/*
* This file is part of lanterna (http://code.google.com/p/lanterna/).
*
* lanterna is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see
* If requested, it handles Control-C input to terminate the program, and hooks
* into Unix WINCH signal to detect when the user has resized the terminal,
* if supported by the JVM.
*
* @author Andreas
* @author Martin
*/
public abstract class UnixLikeTTYTerminal extends UnixLikeTerminal {
private final File ttyDev;
private String sttyStatusToRestore;
/**
* Creates a UnixTerminal using a specified input stream, output stream and character set, with a custom size
* querier instead of using the default one. This way you can override size detection (if you want to force the
* terminal to a fixed size, for example). You also choose how you want ctrl+c key strokes to be handled.
*
* @param ttyDev TTY device file that is representing this terminal session, will be used when calling stty to make
* it operate on this session
* @param terminalInput Input stream to read terminal input from
* @param terminalOutput Output stream to write terminal output to
* @param terminalCharset Character set to use when converting characters to bytes
* @param terminalCtrlCBehaviour Special settings on how the terminal will behave, see {@code UnixTerminalMode} for
* more details
* @throws IOException If there was an I/O error while setting up the terminal
*/
protected UnixLikeTTYTerminal(
File ttyDev,
InputStream terminalInput,
OutputStream terminalOutput,
Charset terminalCharset,
CtrlCBehaviour terminalCtrlCBehaviour) throws IOException {
super(terminalInput,
terminalOutput,
terminalCharset,
terminalCtrlCBehaviour);
this.ttyDev = ttyDev;
// Take ownership of the terminal
realAcquire();
}
@Override
protected void acquire() throws IOException {
// Hack!
}
private void realAcquire() throws IOException {
super.acquire();
}
@Override
protected void registerTerminalResizeListener(final Runnable onResize) throws IOException {
try {
Class signalClass = Class.forName("sun.misc.Signal");
for(Method m : signalClass.getDeclaredMethods()) {
if("handle".equals(m.getName())) {
Object windowResizeHandler = Proxy.newProxyInstance(getClass().getClassLoader(), new Class[]{Class.forName("sun.misc.SignalHandler")}, new InvocationHandler() {
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
if("handle".equals(method.getName())) {
onResize.run();
}
return null;
}
});
m.invoke(null, signalClass.getConstructor(String.class).newInstance("WINCH"), windowResizeHandler);
}
}
}
catch(Throwable ignore) {
// We're probably running on a non-Sun JVM and there's no way to catch signals without resorting to native
// code integration
}
}
@Override
protected void saveTerminalSettings() throws IOException {
sttyStatusToRestore = exec(getSTTYCommand(), "-g").trim();
}
@Override
protected void restoreTerminalSettings() throws IOException {
if(sttyStatusToRestore != null) {
exec(getSTTYCommand(), sttyStatusToRestore);
}
}
@Override
protected void keyEchoEnabled(boolean enabled) throws IOException {
exec(getSTTYCommand(), enabled ? "echo" : "-echo");
}
@Override
protected void canonicalMode(boolean enabled) throws IOException {
exec(getSTTYCommand(), enabled ? "icanon" : "-icanon");
if(!enabled) {
exec(getSTTYCommand(), "min", "1");
}
}
@Override
protected void keyStrokeSignalsEnabled(boolean enabled) throws IOException {
if(enabled) {
exec(getSTTYCommand(), "intr", "^C");
}
else {
exec(getSTTYCommand(), "intr", "undef");
}
}
protected String runSTTYCommand(String... parameters) throws IOException {
List commandLine = new ArrayList(Collections.singletonList(
getSTTYCommand()));
commandLine.addAll(Arrays.asList(parameters));
return exec(commandLine.toArray(new String[commandLine.size()]));
}
protected String exec(String... cmd) throws IOException {
if (ttyDev != null) {
//Here's what we try to do, but that is Java 7+ only:
// processBuilder.redirectInput(ProcessBuilder.Redirect.from(ttyDev));
//instead, for Java 6, we join the cmd into a scriptlet with redirection
//and replace cmd by a call to sh with the scriptlet:
StringBuilder sb = new StringBuilder();
for (String arg : cmd) { sb.append(arg).append(' '); }
sb.append("< ").append(ttyDev);
cmd = new String[] { "sh", "-c", sb.toString() };
}
ProcessBuilder pb = new ProcessBuilder(cmd);
Process process = pb.start();
ByteArrayOutputStream stdoutBuffer = new ByteArrayOutputStream();
InputStream stdout = process.getInputStream();
int readByte = stdout.read();
while(readByte >= 0) {
stdoutBuffer.write(readByte);
readByte = stdout.read();
}
ByteArrayInputStream stdoutBufferInputStream = new ByteArrayInputStream(stdoutBuffer.toByteArray());
BufferedReader reader = new BufferedReader(new InputStreamReader(stdoutBufferInputStream));
StringBuilder builder = new StringBuilder();
String line;
while((line = reader.readLine()) != null) {
builder.append(line);
}
reader.close();
return builder.toString();
}
private String getSTTYCommand() {
return "/bin/stty";
}
}