org.gradle.logging.internal.TerminalDetector.java Source code

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Here is the source code for org.gradle.logging.internal.TerminalDetector.java

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/*
 * Copyright 2010 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.gradle.logging.internal;

import org.apache.commons.io.IOUtils;
import org.fusesource.jansi.WindowsAnsiOutputStream;
import org.gradle.api.GradleException;
import org.gradle.api.UncheckedIOException;
import org.gradle.api.specs.Spec;
import org.gradle.util.OperatingSystem;
import org.gradle.util.PosixUtil;

import java.io.*;

public class TerminalDetector implements Spec<FileDescriptor> {
    public TerminalDetector(File libCacheDir) {
        // Some hackery to prevent JNA from creating a shared lib in the tmp dir, as it does not clean things up
        File tmpDir = new File(libCacheDir, "jna");
        tmpDir.mkdirs();
        String libName = OperatingSystem.current() instanceof OperatingSystem.MacOs ? "libjnidispatch.jnilib"
                : System.mapLibraryName("jnidispatch");
        File libFile = new File(tmpDir, libName);
        if (!libFile.exists()) {
            String resourceName = "/com/sun/jna/" + OperatingSystem.current().getNativePrefix() + "/" + libName;
            try {
                InputStream lib = getClass().getResourceAsStream(resourceName);
                if (lib == null) {
                    throw new GradleException(
                            String.format("Could not locate JNA native lib resource '%s'.", resourceName));
                }
                try {
                    FileOutputStream outputStream = new FileOutputStream(libFile);
                    try {
                        IOUtils.copy(lib, outputStream);
                    } finally {
                        outputStream.close();
                    }
                } finally {
                    lib.close();
                }
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }
        }
        System.setProperty("jna.boot.library.path", tmpDir.getAbsolutePath());
    }

    public boolean isSatisfiedBy(FileDescriptor element) {
        if (OperatingSystem.current().isWindows()) {
            // Use Jansi's detection mechanism
            try {
                new WindowsAnsiOutputStream(new ByteArrayOutputStream());
                return true;
            } catch (IOException ignore) {
                // Not attached to a console
                return false;
            }
        }

        // Use jna-posix to determine if we're connected to a terminal
        if (!PosixUtil.current().isatty(element)) {
            return false;
        }

        // Dumb terminal doesn't support control codes. Should really be using termcap database.
        String term = System.getenv("TERM");
        if (term != null && term.equals("dumb")) {
            return false;
        }

        // Assume a terminal
        return true;
    }
}