org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java - sop/jgit - Git at Google

 /*
  * Copyright (C) 2009, Google Inc.
  * Copyright (C) 2009, Robin Rosenberg <robin.rosenberg@dewire.com>
  * Copyright (C) 2009, Yann Simon <yann.simon.fr@gmail.com>
  * Copyright (C) 2012, Daniel Megert <daniel_megert@ch.ibm.com>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
  * under the terms of the Eclipse Distribution License v1.0 which
  * accompanies this distribution, is reproduced below, and is
  * available at http://www.eclipse.org/org/documents/edl-v10.php
  *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or
  * without modification, are permitted provided that the following
  * conditions are met:
  *
  * - Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  *
  * - Redistributions in binary form must reproduce the above
  *   copyright notice, this list of conditions and the following
  *   disclaimer in the documentation and/or other materials provided
  *   with the distribution.
  *
  * - Neither the name of the Eclipse Foundation, Inc. nor the
  *   names of its contributors may be used to endorse or promote
  *   products derived from this software without specific prior
  *   written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 package org.eclipse.jgit.util;

 import java.io.File;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Locale;
 import java.util.TimeZone;

 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.ObjectChecker;
 import org.eclipse.jgit.storage.file.FileBasedConfig;
 import org.eclipse.jgit.util.time.MonotonicClock;
 import org.eclipse.jgit.util.time.MonotonicSystemClock;

 /**
  * Interface to read values from the system.
  * <p>
  * When writing unit tests, extending this interface with a custom class
  * permits to simulate an access to a system variable or property and
  * permits to control the user's global configuration.
  * </p>
  */
 public abstract class SystemReader {
 	private static final SystemReader DEFAULT;

 	private static Boolean isMacOS;

 	private static Boolean isWindows;

 	static {
 		SystemReader r = new Default();
 		r.init();
 		DEFAULT = r;
 	}

 	private static class Default extends SystemReader {
 		private volatile String hostname;

 		@Override
 		public String getenv(String variable) {
 			return System.getenv(variable);
 		}

 		@Override
 		public String getProperty(String key) {
 			return System.getProperty(key);
 		}

 		@Override
 		public FileBasedConfig openSystemConfig(Config parent, FS fs) {
 			File configFile = fs.getGitSystemConfig();
 			if (configFile == null) {
 				return new FileBasedConfig(null, fs) {
 					@Override
 					public void load() {
 						// empty, do not load
 					}

 					@Override
 					public boolean isOutdated() {
 						// regular class would bomb here
 						return false;
 					}
 				};
 			}
 			return new FileBasedConfig(parent, configFile, fs);
 		}

 		@Override
 		public FileBasedConfig openUserConfig(Config parent, FS fs) {
 			final File home = fs.userHome();
 			return new FileBasedConfig(parent, new File(home, ".gitconfig"), fs); //$NON-NLS-1$
 		}

 		@Override
 		public String getHostname() {
 			if (hostname == null) {
 				try {
 					InetAddress localMachine = InetAddress.getLocalHost();
 					hostname = localMachine.getCanonicalHostName();
 				} catch (UnknownHostException e) {
 					// we do nothing
 					hostname = "localhost"; //$NON-NLS-1$
 				}
 				assert hostname != null;
 			}
 			return hostname;
 		}

 		@Override
 		public long getCurrentTime() {
 			return System.currentTimeMillis();
 		}

 		@Override
 		public int getTimezone(long when) {
 			return getTimeZone().getOffset(when) / (60 * 1000);
 		}
 	}

 	private static SystemReader INSTANCE = DEFAULT;

 	/** @return the live instance to read system properties. */
 	public static SystemReader getInstance() {
 		return INSTANCE;
 	}

 	/**
 	 * @param newReader
 	 *            the new instance to use when accessing properties, or null for
 	 *            the default instance.
 	 */
 	public static void setInstance(SystemReader newReader) {
 		isMacOS = null;
 		isWindows = null;
 		if (newReader == null)
 			INSTANCE = DEFAULT;
 		else {
 			newReader.init();
 			INSTANCE = newReader;
 		}
 	}

 	private ObjectChecker platformChecker;

 	private void init() {
 		// Creating ObjectChecker must be deferred. Unit tests change
 		// behavior of is{Windows,MacOS} in constructor of subclass.
 		if (platformChecker == null)
 			setPlatformChecker();
 	}

 	/**
 	 * Should be used in tests when the platform is explicitly changed.
 	 *
 	 * @since 3.6
 	 */
 	protected final void setPlatformChecker() {
 		platformChecker = new ObjectChecker()
 			.setSafeForWindows(isWindows())
 			.setSafeForMacOS(isMacOS());
 	}

 	/**
 	 * Gets the hostname of the local host. If no hostname can be found, the
 	 * hostname is set to the default value "localhost".
 	 *
 	 * @return the canonical hostname
 	 */
 	public abstract String getHostname();

 	/**
 	 * @param variable system variable to read
 	 * @return value of the system variable
 	 */
 	public abstract String getenv(String variable);

 	/**
 	 * @param key of the system property to read
 	 * @return value of the system property
 	 */
 	public abstract String getProperty(String key);

 	/**
 	 * @param parent
 	 *            a config with values not found directly in the returned config
 	 * @param fs
 	 *            the file system abstraction which will be necessary to perform
 	 *            certain file system operations.
 	 * @return the git configuration found in the user home
 	 */
 	public abstract FileBasedConfig openUserConfig(Config parent, FS fs);

 	/**
 	 * @param parent
 	 *            a config with values not found directly in the returned
 	 *            config. Null is a reasonable value here.
 	 * @param fs
 	 *            the file system abstraction which will be necessary to perform
 	 *            certain file system operations.
 	 * @return the gitonfig configuration found in the system-wide "etc"
 	 *         directory
 	 */
 	public abstract FileBasedConfig openSystemConfig(Config parent, FS fs);

 	/**
 	 * @return the current system time
 	 */
 	public abstract long getCurrentTime();

 	/**
 	 * @return clock instance preferred by this system.
 	 * @since 4.6
 	 */
 	public MonotonicClock getClock() {
 		return new MonotonicSystemClock();
 	}

 	/**
 	 * @param when TODO
 	 * @return the local time zone
 	 */
 	public abstract int getTimezone(long when);

 	/**
 	 * @return system time zone, possibly mocked for testing
 	 * @since 1.2
 	 */
 	public TimeZone getTimeZone() {
 		return TimeZone.getDefault();
 	}

 	/**
 	 * @return the locale to use
 	 * @since 1.2
 	 */
 	public Locale getLocale() {
 		return Locale.getDefault();
 	}

 	/**
 	 * Returns a simple date format instance as specified by the given pattern.
 	 *
 	 * @param pattern
 	 *            the pattern as defined in
 	 *            {@link SimpleDateFormat#SimpleDateFormat(String)}
 	 * @return the simple date format
 	 * @since 2.0
 	 */
 	public SimpleDateFormat getSimpleDateFormat(String pattern) {
 		return new SimpleDateFormat(pattern);
 	}

 	/**
 	 * Returns a simple date format instance as specified by the given pattern.
 	 *
 	 * @param pattern
 	 *            the pattern as defined in
 	 *            {@link SimpleDateFormat#SimpleDateFormat(String)}
 	 * @param locale
 	 *            locale to be used for the {@code SimpleDateFormat}
 	 * @return the simple date format
 	 * @since 3.2
 	 */
 	public SimpleDateFormat getSimpleDateFormat(String pattern, Locale locale) {
 		return new SimpleDateFormat(pattern, locale);
 	}

 	/**
 	 * Returns a date/time format instance for the given styles.
 	 *
 	 * @param dateStyle
 	 *            the date style as specified in
 	 *            {@link DateFormat#getDateTimeInstance(int, int)}
 	 * @param timeStyle
 	 *            the time style as specified in
 	 *            {@link DateFormat#getDateTimeInstance(int, int)}
 	 * @return the date format
 	 * @since 2.0
 	 */
 	public DateFormat getDateTimeInstance(int dateStyle, int timeStyle) {
 		return DateFormat.getDateTimeInstance(dateStyle, timeStyle);
 	}

 	/**
 	 * @return true if we are running on a Windows.
 	 */
 	public boolean isWindows() {
 		if (isWindows == null) {
 			String osDotName = getOsName();
 			isWindows = Boolean.valueOf(osDotName.startsWith("Windows")); //$NON-NLS-1$
 		}
 		return isWindows.booleanValue();
 	}

 	/**
 	 * @return true if we are running on Mac OS X
 	 */
 	public boolean isMacOS() {
 		if (isMacOS == null) {
 			String osDotName = getOsName();
 			isMacOS = Boolean.valueOf(
 					"Mac OS X".equals(osDotName) || "Darwin".equals(osDotName)); //$NON-NLS-1$ //$NON-NLS-2$
 		}
 		return isMacOS.booleanValue();
 	}

 	private String getOsName() {
 		return AccessController.doPrivileged(new PrivilegedAction<String>() {
 			@Override
 			public String run() {
 				return getProperty("os.name"); //$NON-NLS-1$
 			}
 		});
 	}

 	/**
 	 * Check tree path entry for validity.
 	 * <p>
 	 * Scans a multi-directory path string such as {@code "src/main.c"}.
 	 *
 	 * @param path path string to scan.
 	 * @throws CorruptObjectException path is invalid.
 	 * @since 3.6
 	 */
 	public void checkPath(String path) throws CorruptObjectException {
 		platformChecker.checkPath(path);
 	}

 	/**
 	 * Check tree path entry for validity.
 	 * <p>
 	 * Scans a multi-directory path string such as {@code "src/main.c"}.
 	 *
 	 * @param path
 	 *            path string to scan.
 	 * @throws CorruptObjectException
 	 *             path is invalid.
 	 * @since 4.2
 	 */
 	public void checkPath(byte[] path) throws CorruptObjectException {
 		platformChecker.checkPath(path, 0, path.length);
 	}
 }
	/*
	* Copyright (C) 2009, Google Inc.
	* Copyright (C) 2009, Robin Rosenberg <robin.rosenberg@dewire.com>
	* Copyright (C) 2009, Yann Simon <yann.simon.fr@gmail.com>
	* Copyright (C) 2012, Daniel Megert <daniel_megert@ch.ibm.com>
	* and other copyright owners as documented in the project's IP log.
	*
	* This program and the accompanying materials are made available
	* under the terms of the Eclipse Distribution License v1.0 which
	* accompanies this distribution, is reproduced below, and is
	* available at http://www.eclipse.org/org/documents/edl-v10.php
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials provided
	* with the distribution.
	*
	* - Neither the name of the Eclipse Foundation, Inc. nor the
	* names of its contributors may be used to endorse or promote
	* products derived from this software without specific prior
	* written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
	* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
	* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
	* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	package org.eclipse.jgit.util;

	import java.io.File;
	import java.net.InetAddress;
	import java.net.UnknownHostException;
	import java.security.AccessController;
	import java.security.PrivilegedAction;
	import java.text.DateFormat;
	import java.text.SimpleDateFormat;
	import java.util.Locale;
	import java.util.TimeZone;

	import org.eclipse.jgit.errors.CorruptObjectException;
	import org.eclipse.jgit.lib.Config;
	import org.eclipse.jgit.lib.ObjectChecker;
	import org.eclipse.jgit.storage.file.FileBasedConfig;
	import org.eclipse.jgit.util.time.MonotonicClock;
	import org.eclipse.jgit.util.time.MonotonicSystemClock;

	/**
	* Interface to read values from the system.
	* <p>
	* When writing unit tests, extending this interface with a custom class
	* permits to simulate an access to a system variable or property and
	* permits to control the user's global configuration.
	* </p>
	*/
	public abstract class SystemReader {
	private static final SystemReader DEFAULT;

	private static Boolean isMacOS;

	private static Boolean isWindows;

	static {
	SystemReader r = new Default();
	r.init();
	DEFAULT = r;
	}

	private static class Default extends SystemReader {
	private volatile String hostname;

	@Override
	public String getenv(String variable) {
	return System.getenv(variable);
	}

	@Override
	public String getProperty(String key) {
	return System.getProperty(key);
	}

	@Override
	public FileBasedConfig openSystemConfig(Config parent, FS fs) {
	File configFile = fs.getGitSystemConfig();
	if (configFile == null) {
	return new FileBasedConfig(null, fs) {
	@Override
	public void load() {
	// empty, do not load
	}

	@Override
	public boolean isOutdated() {
	// regular class would bomb here
	return false;
	}
	};
	}
	return new FileBasedConfig(parent, configFile, fs);
	}

	@Override
	public FileBasedConfig openUserConfig(Config parent, FS fs) {
	final File home = fs.userHome();
	return new FileBasedConfig(parent, new File(home, ".gitconfig"), fs); //$NON-NLS-1$
	}

	@Override
	public String getHostname() {
	if (hostname == null) {
	try {
	InetAddress localMachine = InetAddress.getLocalHost();
	hostname = localMachine.getCanonicalHostName();
	} catch (UnknownHostException e) {
	// we do nothing
	hostname = "localhost"; //$NON-NLS-1$
	}
	assert hostname != null;
	}
	return hostname;
	}

	@Override
	public long getCurrentTime() {
	return System.currentTimeMillis();
	}

	@Override
	public int getTimezone(long when) {
	return getTimeZone().getOffset(when) / (60 * 1000);
	}
	}

	private static SystemReader INSTANCE = DEFAULT;

	/** @return the live instance to read system properties. */
	public static SystemReader getInstance() {
	return INSTANCE;
	}

	/**
	* @param newReader
	* the new instance to use when accessing properties, or null for
	* the default instance.
	*/
	public static void setInstance(SystemReader newReader) {
	isMacOS = null;
	isWindows = null;
	if (newReader == null)
	INSTANCE = DEFAULT;
	else {
	newReader.init();
	INSTANCE = newReader;
	}
	}

	private ObjectChecker platformChecker;

	private void init() {
	// Creating ObjectChecker must be deferred. Unit tests change
	// behavior of is{Windows,MacOS} in constructor of subclass.
	if (platformChecker == null)
	setPlatformChecker();
	}

	/**
	* Should be used in tests when the platform is explicitly changed.
	*
	* @since 3.6
	*/
	protected final void setPlatformChecker() {
	platformChecker = new ObjectChecker()
	.setSafeForWindows(isWindows())
	.setSafeForMacOS(isMacOS());
	}

	/**
	* Gets the hostname of the local host. If no hostname can be found, the
	* hostname is set to the default value "localhost".
	*
	* @return the canonical hostname
	*/
	public abstract String getHostname();

	/**
	* @param variable system variable to read
	* @return value of the system variable
	*/
	public abstract String getenv(String variable);

	/**
	* @param key of the system property to read
	* @return value of the system property
	*/
	public abstract String getProperty(String key);

	/**
	* @param parent
	* a config with values not found directly in the returned config
	* @param fs
	* the file system abstraction which will be necessary to perform
	* certain file system operations.
	* @return the git configuration found in the user home
	*/
	public abstract FileBasedConfig openUserConfig(Config parent, FS fs);

	/**
	* @param parent
	* a config with values not found directly in the returned
	* config. Null is a reasonable value here.
	* @param fs
	* the file system abstraction which will be necessary to perform
	* certain file system operations.
	* @return the gitonfig configuration found in the system-wide "etc"
	* directory
	*/
	public abstract FileBasedConfig openSystemConfig(Config parent, FS fs);

	/**
	* @return the current system time
	*/
	public abstract long getCurrentTime();

	/**
	* @return clock instance preferred by this system.
	* @since 4.6
	*/
	public MonotonicClock getClock() {
	return new MonotonicSystemClock();
	}

	/**
	* @param when TODO
	* @return the local time zone
	*/
	public abstract int getTimezone(long when);

	/**
	* @return system time zone, possibly mocked for testing
	* @since 1.2
	*/
	public TimeZone getTimeZone() {
	return TimeZone.getDefault();
	}

	/**
	* @return the locale to use
	* @since 1.2
	*/
	public Locale getLocale() {
	return Locale.getDefault();
	}

	/**
	* Returns a simple date format instance as specified by the given pattern.
	*
	* @param pattern
	* the pattern as defined in
	* {@link SimpleDateFormat#SimpleDateFormat(String)}
	* @return the simple date format
	* @since 2.0
	*/
	public SimpleDateFormat getSimpleDateFormat(String pattern) {
	return new SimpleDateFormat(pattern);
	}

	/**
	* Returns a simple date format instance as specified by the given pattern.
	*
	* @param pattern
	* the pattern as defined in
	* {@link SimpleDateFormat#SimpleDateFormat(String)}
	* @param locale
	* locale to be used for the {@code SimpleDateFormat}
	* @return the simple date format
	* @since 3.2
	*/
	public SimpleDateFormat getSimpleDateFormat(String pattern, Locale locale) {
	return new SimpleDateFormat(pattern, locale);
	}

	/**
	* Returns a date/time format instance for the given styles.
	*
	* @param dateStyle
	* the date style as specified in
	* {@link DateFormat#getDateTimeInstance(int, int)}
	* @param timeStyle
	* the time style as specified in
	* {@link DateFormat#getDateTimeInstance(int, int)}
	* @return the date format
	* @since 2.0
	*/
	public DateFormat getDateTimeInstance(int dateStyle, int timeStyle) {
	return DateFormat.getDateTimeInstance(dateStyle, timeStyle);
	}

	/**
	* @return true if we are running on a Windows.
	*/
	public boolean isWindows() {
	if (isWindows == null) {
	String osDotName = getOsName();
	isWindows = Boolean.valueOf(osDotName.startsWith("Windows")); //$NON-NLS-1$
	}
	return isWindows.booleanValue();
	}

	/**
	* @return true if we are running on Mac OS X
	*/
	public boolean isMacOS() {
	if (isMacOS == null) {
	String osDotName = getOsName();
	isMacOS = Boolean.valueOf(
	"Mac OS X".equals(osDotName) \|\| "Darwin".equals(osDotName)); //$NON-NLS-1$ //$NON-NLS-2$
	}
	return isMacOS.booleanValue();
	}

	private String getOsName() {
	return AccessController.doPrivileged(new PrivilegedAction<String>() {
	@Override
	public String run() {
	return getProperty("os.name"); //$NON-NLS-1$
	}
	});
	}

	/**
	* Check tree path entry for validity.
	* <p>
	* Scans a multi-directory path string such as {@code "src/main.c"}.
	*
	* @param path path string to scan.
	* @throws CorruptObjectException path is invalid.
	* @since 3.6
	*/
	public void checkPath(String path) throws CorruptObjectException {
	platformChecker.checkPath(path);
	}

	/**
	* Check tree path entry for validity.
	* <p>
	* Scans a multi-directory path string such as {@code "src/main.c"}.
	*
	* @param path
	* path string to scan.
	* @throws CorruptObjectException
	* path is invalid.
	* @since 4.2
	*/
	public void checkPath(byte[] path) throws CorruptObjectException {
	platformChecker.checkPath(path, 0, path.length);
	}
	}