TerminalBuilder.java
/*
* Copyright (c) 2002-2021, the original author(s).
*
* This software is distributable under the BSD license. See the terms of the
* BSD license in the documentation provided with this software.
*
* https://opensource.org/licenses/BSD-3-Clause
*/
package org.jline.terminal;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.charset.UnsupportedCharsetException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Optional;
import java.util.ServiceLoader;
import java.util.concurrent.atomic.AtomicReference;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import org.jline.terminal.impl.AbstractPosixTerminal;
import org.jline.terminal.impl.AbstractTerminal;
import org.jline.terminal.impl.DumbTerminal;
import org.jline.terminal.spi.TerminalProvider;
import org.jline.utils.Log;
import org.jline.utils.OSUtils;
/**
* Builder class to create terminals.
*/
public final class TerminalBuilder {
//
// System properties
//
public static final String PROP_ENCODING = "org.jline.terminal.encoding";
public static final String PROP_CODEPAGE = "org.jline.terminal.codepage";
public static final String PROP_TYPE = "org.jline.terminal.type";
public static final String PROP_PROVIDERS = "org.jline.terminal.providers";
public static final String PROP_PROVIDERS_DEFAULT = "jansi,jna,exec";
public static final String PROP_JNA = "org.jline.terminal.jna";
public static final String PROP_JANSI = "org.jline.terminal.jansi";
public static final String PROP_EXEC = "org.jline.terminal.exec";
public static final String PROP_DUMB = "org.jline.terminal.dumb";
public static final String PROP_DUMB_COLOR = "org.jline.terminal.dumb.color";
public static final String PROP_OUTPUT = "org.jline.terminal.output";
public static final String PROP_OUTPUT_OUT = "out";
public static final String PROP_OUTPUT_ERR = "err";
public static final String PROP_OUTPUT_OUT_ERR = "out-err";
public static final String PROP_OUTPUT_ERR_OUT = "err-out";
//
// Other system properties controlling various jline parts
//
public static final String PROP_NON_BLOCKING_READS = "org.jline.terminal.pty.nonBlockingReads";
public static final String PROP_COLOR_DISTANCE = "org.jline.utils.colorDistance";
public static final String PROP_DISABLE_ALTERNATE_CHARSET = "org.jline.utils.disableAlternateCharset";
//
// System properties controlling how FileDescriptor are create.
// The value can be a comma separated list of defined mechanisms.
//
public static final String PROP_FILE_DESCRIPTOR_CREATION_MODE = "org.jline.terminal.pty.fileDescriptorCreationMode";
public static final String PROP_FILE_DESCRIPTOR_CREATION_MODE_NATIVE = "native";
public static final String PROP_FILE_DESCRIPTOR_CREATION_MODE_REFLECTION = "reflection";
public static final String PROP_FILE_DESCRIPTOR_CREATION_MODE_DEFAULT = "reflection,native";
//
// Terminal output control
//
public enum SystemOutput {
SysOut,
SysErr,
SysOutOrSysErr,
SysErrOrSysOut
}
/**
* Returns the default system terminal.
* Terminals should be closed properly using the {@link Terminal#close()}
* method in order to restore the original terminal state.
*
* <p>
* This call is equivalent to:
* <code>builder().build()</code>
* </p>
*
* @return the default system terminal
* @throws IOException if an error occurs
*/
public static Terminal terminal() throws IOException {
return builder().build();
}
/**
* Creates a new terminal builder instance.
*
* @return a builder
*/
public static TerminalBuilder builder() {
return new TerminalBuilder();
}
private static final AtomicReference<Terminal> SYSTEM_TERMINAL = new AtomicReference<>();
private static final AtomicReference<Terminal> TERMINAL_OVERRIDE = new AtomicReference<>();
private String name;
private InputStream in;
private OutputStream out;
private String type;
private Charset encoding;
private int codepage;
private Boolean system;
private SystemOutput systemOutput;
private Boolean jna;
private Boolean jansi;
private Boolean exec;
private Boolean dumb;
private Boolean color;
private Attributes attributes;
private Size size;
private boolean nativeSignals = false;
private Terminal.SignalHandler signalHandler = Terminal.SignalHandler.SIG_DFL;
private boolean paused = false;
private TerminalBuilder() {}
public TerminalBuilder name(String name) {
this.name = name;
return this;
}
public TerminalBuilder streams(InputStream in, OutputStream out) {
this.in = in;
this.out = out;
return this;
}
public TerminalBuilder system(boolean system) {
this.system = system;
return this;
}
/**
* Indicates which standard stream should be used when displaying to the terminal.
* The default is to use the system output stream.
* Building a system terminal will fail if one of the stream specified is not linked
* to the controlling terminal.
*
* @param systemOutput The mode to choose the output stream.
* @return The builder.
*/
public TerminalBuilder systemOutput(SystemOutput systemOutput) {
this.systemOutput = systemOutput;
return this;
}
public TerminalBuilder jna(boolean jna) {
this.jna = jna;
return this;
}
public TerminalBuilder jansi(boolean jansi) {
this.jansi = jansi;
return this;
}
public TerminalBuilder exec(boolean exec) {
this.exec = exec;
return this;
}
public TerminalBuilder dumb(boolean dumb) {
this.dumb = dumb;
return this;
}
public TerminalBuilder type(String type) {
this.type = type;
return this;
}
public TerminalBuilder color(boolean color) {
this.color = color;
return this;
}
/**
* Set the encoding to use for reading/writing from the console.
* If {@code null} (the default value), JLine will automatically select
* a {@link Charset}, usually the default system encoding. However,
* on some platforms (e.g. Windows) it may use a different one depending
* on the {@link Terminal} implementation.
*
* <p>Use {@link Terminal#encoding()} to get the {@link Charset} that
* should be used for a {@link Terminal}.</p>
*
* @param encoding The encoding to use or null to automatically select one
* @return The builder
* @throws UnsupportedCharsetException If the given encoding is not supported
* @see Terminal#encoding()
*/
public TerminalBuilder encoding(String encoding) throws UnsupportedCharsetException {
return encoding(encoding != null ? Charset.forName(encoding) : null);
}
/**
* Set the {@link Charset} to use for reading/writing from the console.
* If {@code null} (the default value), JLine will automatically select
* a {@link Charset}, usually the default system encoding. However,
* on some platforms (e.g. Windows) it may use a different one depending
* on the {@link Terminal} implementation.
*
* <p>Use {@link Terminal#encoding()} to get the {@link Charset} that
* should be used to read/write from a {@link Terminal}.</p>
*
* @param encoding The encoding to use or null to automatically select one
* @return The builder
* @see Terminal#encoding()
*/
public TerminalBuilder encoding(Charset encoding) {
this.encoding = encoding;
return this;
}
/**
* @param codepage the codepage
* @return The builder
* @deprecated JLine now writes Unicode output independently from the selected
* code page. Using this option will only make it emulate the selected code
* page for {@link Terminal#input()} and {@link Terminal#output()}.
*/
@Deprecated
public TerminalBuilder codepage(int codepage) {
this.codepage = codepage;
return this;
}
/**
* Attributes to use when creating a non system terminal,
* i.e. when the builder has been given the input and
* output streams using the {@link #streams(InputStream, OutputStream)} method
* or when {@link #system(boolean)} has been explicitly called with
* <code>false</code>.
*
* @param attributes the attributes to use
* @return The builder
* @see #size(Size)
* @see #system(boolean)
*/
public TerminalBuilder attributes(Attributes attributes) {
this.attributes = attributes;
return this;
}
/**
* Initial size to use when creating a non system terminal,
* i.e. when the builder has been given the input and
* output streams using the {@link #streams(InputStream, OutputStream)} method
* or when {@link #system(boolean)} has been explicitly called with
* <code>false</code>.
*
* @param size the initial size
* @return The builder
* @see #attributes(Attributes)
* @see #system(boolean)
*/
public TerminalBuilder size(Size size) {
this.size = size;
return this;
}
public TerminalBuilder nativeSignals(boolean nativeSignals) {
this.nativeSignals = nativeSignals;
return this;
}
public TerminalBuilder signalHandler(Terminal.SignalHandler signalHandler) {
this.signalHandler = signalHandler;
return this;
}
/**
* Initial paused state of the terminal (defaults to false).
* By default, the terminal is started, but in some cases,
* one might want to make sure the input stream is not consumed
* before needed, in which case the terminal needs to be created
* in a paused state.
* @param paused the initial paused state
* @return The builder
* @see Terminal#pause()
*/
public TerminalBuilder paused(boolean paused) {
this.paused = paused;
return this;
}
public Terminal build() throws IOException {
Terminal override = TERMINAL_OVERRIDE.get();
Terminal terminal = override != null ? override : doBuild();
if (override != null) {
Log.debug(() -> "Overriding terminal with global value set by TerminalBuilder.setTerminalOverride");
}
Log.debug(() -> "Using terminal " + terminal.getClass().getSimpleName());
if (terminal instanceof AbstractPosixTerminal) {
Log.debug(() -> "Using pty "
+ ((AbstractPosixTerminal) terminal).getPty().getClass().getSimpleName());
}
return terminal;
}
private Terminal doBuild() throws IOException {
String name = this.name;
if (name == null) {
name = "JLine terminal";
}
Charset encoding = this.encoding;
if (encoding == null) {
String charsetName = System.getProperty(PROP_ENCODING);
if (charsetName != null && Charset.isSupported(charsetName)) {
encoding = Charset.forName(charsetName);
}
}
if (encoding == null) {
int codepage = this.codepage;
if (codepage <= 0) {
String str = System.getProperty(PROP_CODEPAGE);
if (str != null) {
codepage = Integer.parseInt(str);
}
}
if (codepage >= 0) {
encoding = getCodepageCharset(codepage);
} else {
encoding = StandardCharsets.UTF_8;
}
}
String type = this.type;
if (type == null) {
type = System.getProperty(PROP_TYPE);
}
if (type == null) {
type = System.getenv("TERM");
}
Boolean jna = this.jna;
if (jna == null) {
jna = getBoolean(PROP_JNA, true);
}
Boolean jansi = this.jansi;
if (jansi == null) {
jansi = getBoolean(PROP_JANSI, true);
}
Boolean exec = this.exec;
if (exec == null) {
exec = getBoolean(PROP_EXEC, true);
}
Boolean dumb = this.dumb;
if (dumb == null) {
dumb = getBoolean(PROP_DUMB, null);
}
IllegalStateException exception = new IllegalStateException("Unable to create a terminal");
List<TerminalProvider> providers = new ArrayList<>();
if (jna) {
try {
TerminalProvider provider = TerminalProvider.load("jna");
providers.add(provider);
} catch (Throwable t) {
Log.debug("Unable to load JNA support: ", t);
exception.addSuppressed(t);
}
}
if (jansi) {
try {
TerminalProvider provider = TerminalProvider.load("jansi");
providers.add(provider);
} catch (Throwable t) {
Log.debug("Unable to load JANSI support: ", t);
exception.addSuppressed(t);
}
}
if (exec) {
try {
TerminalProvider provider = TerminalProvider.load("exec");
providers.add(provider);
} catch (Throwable t) {
Log.debug("Unable to load EXEC support: ", t);
exception.addSuppressed(t);
}
}
List<String> order = Arrays.asList(
System.getProperty(PROP_PROVIDERS, PROP_PROVIDERS_DEFAULT).split(","));
providers.sort(Comparator.comparing(l -> {
int idx = order.indexOf(l);
return idx >= 0 ? idx : Integer.MAX_VALUE;
}));
Terminal terminal = null;
if ((system != null && system) || (system == null && in == null && out == null)) {
if (system != null
&& ((in != null && !in.equals(System.in))
|| (out != null && !out.equals(System.out) && !out.equals(System.err)))) {
throw new IllegalArgumentException("Cannot create a system terminal using non System streams");
}
if (attributes != null || size != null) {
Log.warn("Attributes and size fields are ignored when creating a system terminal");
}
if (out != null) {
if (out.equals(System.out)) {
systemOutput = SystemOutput.SysOut;
} else if (out.equals(System.err)) {
systemOutput = SystemOutput.SysErr;
}
}
if (systemOutput == null) {
String str = System.getProperty(PROP_OUTPUT);
if (str != null) {
switch (str.trim().toLowerCase(Locale.ROOT)) {
case PROP_OUTPUT_OUT:
systemOutput = SystemOutput.SysOut;
break;
case PROP_OUTPUT_ERR:
systemOutput = SystemOutput.SysErr;
break;
case PROP_OUTPUT_OUT_ERR:
systemOutput = SystemOutput.SysOutOrSysErr;
break;
case PROP_OUTPUT_ERR_OUT:
systemOutput = SystemOutput.SysErrOrSysOut;
break;
default:
Log.debug("Unsupported value for " + PROP_OUTPUT + ": " + str + ". Supported values are: "
+ String.join(
", ",
PROP_OUTPUT_OUT,
PROP_OUTPUT_ERR,
PROP_OUTPUT_OUT_ERR,
PROP_OUTPUT_ERR_OUT)
+ ".");
}
}
}
if (systemOutput == null) {
systemOutput = SystemOutput.SysOutOrSysErr;
}
Map<TerminalProvider.Stream, Boolean> system = Stream.of(TerminalProvider.Stream.values())
.collect(Collectors.toMap(
stream -> stream, stream -> providers.stream().anyMatch(p -> p.isSystemStream(stream))));
TerminalProvider.Stream console = select(system, systemOutput);
if (system.get(TerminalProvider.Stream.Input) && console != null) {
if (attributes != null || size != null) {
Log.warn("Attributes and size fields are ignored when creating a system terminal");
}
boolean ansiPassThrough = OSUtils.IS_CONEMU;
// Cygwin defaults to XTERM, but actually supports 256 colors,
// so if the value comes from the environment, change it to xterm-256color
if ((OSUtils.IS_CYGWIN || OSUtils.IS_MSYSTEM)
&& "xterm".equals(type)
&& this.type == null
&& System.getProperty(PROP_TYPE) == null) {
type = "xterm-256color";
}
for (TerminalProvider provider : providers) {
if (terminal == null) {
try {
terminal = provider.sysTerminal(
name,
type,
ansiPassThrough,
encoding,
nativeSignals,
signalHandler,
paused,
console);
} catch (Throwable t) {
Log.debug("Error creating " + provider.name() + " based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
}
if (terminal == null && OSUtils.IS_WINDOWS && !jna && !jansi && (dumb == null || !dumb)) {
throw new IllegalStateException("Unable to create a system terminal. On windows, either "
+ "JNA or JANSI library is required. Make sure to add one of those in the classpath.");
}
}
if (terminal instanceof AbstractTerminal) {
AbstractTerminal t = (AbstractTerminal) terminal;
if (SYSTEM_TERMINAL.compareAndSet(null, t)) {
t.setOnClose(() -> SYSTEM_TERMINAL.compareAndSet(t, null));
} else {
exception.addSuppressed(new IllegalStateException("A system terminal is already running. "
+ "Make sure to use the created system Terminal on the LineReaderBuilder if you're using one "
+ "or that previously created system Terminals have been correctly closed."));
terminal.close();
terminal = null;
}
}
if (terminal == null && (dumb == null || dumb)) {
// forced colored dumb terminal
Boolean color = this.color;
if (color == null) {
color = getBoolean(PROP_DUMB_COLOR, null);
}
if (dumb == null) {
// detect emacs using the env variable
if (color == null) {
String emacs = System.getenv("INSIDE_EMACS");
if (emacs != null && emacs.contains("comint")) {
color = true;
}
}
// detect Intellij Idea
if (color == null) {
// using the env variable on windows
String ideHome = System.getenv("IDE_HOME");
if (ideHome != null) {
color = true;
} else {
// using the parent process command on unix/mac
String command = getParentProcessCommand();
if (command != null && command.endsWith("/idea")) {
color = true;
}
}
}
if (color == null) {
color = console != null && System.getenv("TERM") != null;
}
if (Log.isDebugEnabled()) {
Log.warn("input is tty: {}", system.get(TerminalProvider.Stream.Input));
Log.warn("output is tty: {}", system.get(TerminalProvider.Stream.Output));
Log.warn("error is tty: {}", system.get(TerminalProvider.Stream.Error));
Log.warn("Creating a dumb terminal", exception);
} else {
Log.warn(
"Unable to create a system terminal, creating a dumb terminal (enable debug logging for more information)");
}
} else {
if (color == null) {
color = false;
}
}
terminal = new DumbTerminal(
name,
color ? Terminal.TYPE_DUMB_COLOR : Terminal.TYPE_DUMB,
new FileInputStream(FileDescriptor.in),
new FileOutputStream(
console == TerminalProvider.Stream.Output ? FileDescriptor.out : FileDescriptor.err),
encoding,
signalHandler);
}
} else {
for (TerminalProvider provider : providers) {
if (terminal == null) {
try {
terminal = provider.newTerminal(
name, type, in, out, encoding, signalHandler, paused, attributes, size);
} catch (Throwable t) {
Log.debug("Error creating " + provider.name() + " based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
}
}
if (terminal == null) {
throw exception;
}
return terminal;
}
private TerminalProvider.Stream select(Map<TerminalProvider.Stream, Boolean> system, SystemOutput systemOutput) {
switch (systemOutput) {
case SysOut:
return select(system, TerminalProvider.Stream.Output);
case SysErr:
return select(system, TerminalProvider.Stream.Error);
case SysOutOrSysErr:
return select(system, TerminalProvider.Stream.Output, TerminalProvider.Stream.Error);
case SysErrOrSysOut:
return select(system, TerminalProvider.Stream.Error, TerminalProvider.Stream.Output);
}
return null;
}
private static TerminalProvider.Stream select(
Map<TerminalProvider.Stream, Boolean> system, TerminalProvider.Stream... streams) {
for (TerminalProvider.Stream s : streams) {
if (system.get(s)) {
return s;
}
}
return null;
}
private static String getParentProcessCommand() {
try {
Class<?> phClass = Class.forName("java.lang.ProcessHandle");
Object current = phClass.getMethod("current").invoke(null);
Object parent = ((Optional<?>) phClass.getMethod("parent").invoke(current)).orElse(null);
Method infoMethod = phClass.getMethod("info");
Object info = infoMethod.invoke(parent);
Object command = ((Optional<?>)
infoMethod.getReturnType().getMethod("command").invoke(info))
.orElse(null);
return (String) command;
} catch (Throwable t) {
return null;
}
}
private static Boolean getBoolean(String name, Boolean def) {
try {
String str = System.getProperty(name);
if (str != null) {
return Boolean.parseBoolean(str);
}
} catch (IllegalArgumentException | NullPointerException e) {
}
return def;
}
private static <S> S load(Class<S> clazz) {
return ServiceLoader.load(clazz, clazz.getClassLoader()).iterator().next();
}
private static final int UTF8_CODE_PAGE = 65001;
private static Charset getCodepageCharset(int codepage) {
// http://docs.oracle.com/javase/6/docs/technotes/guides/intl/encoding.doc.html
if (codepage == UTF8_CODE_PAGE) {
return StandardCharsets.UTF_8;
}
String charsetMS = "ms" + codepage;
if (Charset.isSupported(charsetMS)) {
return Charset.forName(charsetMS);
}
String charsetCP = "cp" + codepage;
if (Charset.isSupported(charsetCP)) {
return Charset.forName(charsetCP);
}
return Charset.defaultCharset();
}
/**
* Allows an application to override the result of {@link #build()}. The
* intended use case is to allow a container or server application to control
* an embedded application that uses a LineReader that uses Terminal
* constructed with TerminalBuilder.build but provides no public api for setting
* the <code>LineReader</code> of the {@link Terminal}. For example, the sbt
* build tool uses a <code>LineReader</code> to implement an interactive shell.
* One of its supported commands is <code>console</code> which invokes
* the scala REPL. The scala REPL also uses a <code>LineReader</code> and it
* is necessary to override the {@link Terminal} used by the the REPL to
* share the same {@link Terminal} instance used by sbt.
*
* <p>
* When this method is called with a non-null {@link Terminal}, all subsequent
* calls to {@link #build()} will return the provided {@link Terminal} regardless
* of how the {@link TerminalBuilder} was constructed. The default behavior
* of {@link TerminalBuilder} can be restored by calling setTerminalOverride
* with a null {@link Terminal}
* </p>
*
* <p>
* Usage of setTerminalOverride should be restricted to cases where it
* isn't possible to update the api of the nested application to accept
* a {@link Terminal instance}.
* </p>
*
* @param terminal the {@link Terminal} to globally override
*/
@Deprecated
public static void setTerminalOverride(final Terminal terminal) {
TERMINAL_OVERRIDE.set(terminal);
}
}