platform/util/src/com/intellij/openapi/util/io/FileSystemUtil.java - platform/tools/idea - Git at Google

 /*
  * Copyright 2000-2014 JetBrains s.r.o.
  *
  * 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 com.intellij.openapi.util.io;

 import com.intellij.Patches;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.util.SystemInfo;
 import com.intellij.openapi.util.io.win32.FileInfo;
 import com.intellij.openapi.util.io.win32.IdeaWin32;
 import com.intellij.util.ArrayUtil;
 import com.intellij.util.SystemProperties;
 import com.sun.jna.Library;
 import com.sun.jna.Memory;
 import com.sun.jna.Native;
 import com.sun.jna.Pointer;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.annotations.TestOnly;

 import java.io.File;
 import java.io.IOException;
 import java.lang.reflect.Array;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.*;

 import static com.intellij.util.BitUtil.isSet;
 import static com.intellij.util.BitUtil.notSet;

 /**
  * @version 11.1
  */
 public class FileSystemUtil {
   static final String FORCE_USE_NIO2_KEY = "idea.io.use.nio2";
   static final String COARSE_TIMESTAMP = "idea.io.coarse.ts";

   private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.util.io.FileSystemUtil");

   private abstract static class Mediator {
     @Nullable
     protected abstract FileAttributes getAttributes(@NotNull String path) throws Exception;

     @Nullable
     protected abstract String resolveSymLink(@NotNull String path) throws Exception;

     protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception { return false; }

     @NotNull
     private String getName() { return getClass().getSimpleName().replace("MediatorImpl", ""); }
   }

   @NotNull
   private static Mediator ourMediator = getMediator();

   private static Mediator getMediator() {
     Throwable error = null;
     final boolean forceUseNio2 = SystemProperties.getBooleanProperty(FORCE_USE_NIO2_KEY, false);

     if (!forceUseNio2) {
       if (SystemInfo.isWindows && IdeaWin32.isAvailable()) {
         try {
           return check(new IdeaWin32MediatorImpl());
         }
         catch (Throwable t) {
           error = t;
         }
       }
       else if (SystemInfo.isLinux || SystemInfo.isMac || SystemInfo.isSolaris || SystemInfo.isFreeBSD) {
         try {
           return check(new JnaUnixMediatorImpl());
         }
         catch (Throwable t) {
           error = t;
         }
       }
     }

     if (SystemInfo.isJavaVersionAtLeast("1.7") && !"1.7.0-ea".equals(SystemInfo.JAVA_VERSION)) {
       try {
         return check(new Nio2MediatorImpl());
       }
       catch (Throwable t) {
         error = t;
       }
     }

     final String message =
       "Failed to load filesystem access layer (" + SystemInfo.OS_NAME + ", " + SystemInfo.JAVA_VERSION + ", " + forceUseNio2 + ")";
     LOG.error(message, error);

     return new FallbackMediatorImpl();
   }

   private static Mediator check(final Mediator mediator) throws Exception {
     final String quickTestPath = SystemInfo.isWindows ? "C:\\" :  "/";
     mediator.getAttributes(quickTestPath);
     return mediator;
   }

   private FileSystemUtil() { }

   @Nullable
   public static FileAttributes getAttributes(@NotNull String path) {
     try {
       return ourMediator.getAttributes(path);
     }
     catch (Exception e) {
       LOG.warn(e);
     }
     return null;
   }

   @Nullable
   public static FileAttributes getAttributes(@NotNull File file) {
     return getAttributes(file.getPath());
   }

   public static long lastModified(@NotNull File file) {
     FileAttributes attributes = getAttributes(file);
     return attributes != null ? attributes.lastModified : 0;
   }

   /**
    * Checks if a last element in the path is a symlink.
    */
   public static boolean isSymLink(@NotNull String path) {
     if (SystemInfo.areSymLinksSupported) {
       final FileAttributes attributes = getAttributes(path);
       return attributes != null && attributes.isSymLink();
     }
     return false;
   }

   /**
    * Checks if a last element in the path is a symlink.
    */
   public static boolean isSymLink(@NotNull File file) {
     return isSymLink(file.getAbsolutePath());
   }

   @Nullable
   public static String resolveSymLink(@NotNull String path) {
     try {
       final String realPath = ourMediator.resolveSymLink(path);
       if (realPath != null && new File(realPath).exists()) {
         return realPath;
       }
     }
     catch (Exception e) {
       LOG.warn(e);
     }
     return null;
   }

   @Nullable
   public static String resolveSymLink(@NotNull File file) {
     return resolveSymLink(file.getAbsolutePath());
   }

   /** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
   @SuppressWarnings("UnusedDeclaration")
   public static int getPermissions(@NotNull String path) {
     return -1;
   }

   /** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
   @SuppressWarnings("UnusedDeclaration")
   public static int getPermissions(@NotNull File file) {
     return -1;
   }

   /** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
   @SuppressWarnings("UnusedDeclaration")
   public static void setPermissions(@NotNull String path, int permissions) { }

   /** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
   @SuppressWarnings({"UnusedDeclaration", "deprecation"})
   public static void setPermissions(@NotNull File file, int permissions) { }

   /**
    * Gives the second file permissions of the first one if possible; returns true if succeed.
    * Will do nothing on Windows.
    */
   public static boolean clonePermissions(@NotNull String source, @NotNull String target) {
     try {
       return ourMediator.clonePermissions(source, target);
     }
     catch (Exception e) {
       LOG.warn(e);
       return false;
     }
   }


   private static class Nio2MediatorImpl extends Mediator {
     private final Object myDefaultFileSystem;
     private final Method myGetPath;
     private final Method myIsSymbolicLink;
     private final Object myLinkOptions;
     private final Object myNoFollowLinkOptions;
     private final Method myReadAttributes;
     private final Method mySetAttribute;
     private final Method myToMillis;
     private final String mySchema;

     private Nio2MediatorImpl() throws Exception {
       //noinspection ConstantConditions
       assert Patches.USE_REFLECTION_TO_ACCESS_JDK7;

       myDefaultFileSystem = Class.forName("java.nio.file.FileSystems").getMethod("getDefault").invoke(null);

       final Class<?> fsClass = Class.forName("java.nio.file.FileSystem");
       myGetPath = fsClass.getMethod("getPath", String.class, String[].class);
       myGetPath.setAccessible(true);

       final Class<?> pathClass = Class.forName("java.nio.file.Path");
       final Class<?> filesClass = Class.forName("java.nio.file.Files");
       myIsSymbolicLink = filesClass.getMethod("isSymbolicLink", pathClass);
       myIsSymbolicLink.setAccessible(true);

       final Class<?> linkOptClass = Class.forName("java.nio.file.LinkOption");
       myLinkOptions = Array.newInstance(linkOptClass, 0);
       myNoFollowLinkOptions = Array.newInstance(linkOptClass, 1);
       Array.set(myNoFollowLinkOptions, 0, linkOptClass.getField("NOFOLLOW_LINKS").get(null));

       final Class<?> linkOptArrClass = myLinkOptions.getClass();
       myReadAttributes = filesClass.getMethod("readAttributes", pathClass, String.class, linkOptArrClass);
       myReadAttributes.setAccessible(true);
       mySetAttribute = filesClass.getMethod("setAttribute", pathClass, String.class, Object.class, linkOptArrClass);
       mySetAttribute.setAccessible(true);

       final Class<?> fileTimeClass = Class.forName("java.nio.file.attribute.FileTime");
       myToMillis = fileTimeClass.getMethod("toMillis");
       myToMillis.setAccessible(true);

       mySchema = SystemInfo.isWindows ? "dos:*" : "posix:*";
     }

     @Override
     protected FileAttributes getAttributes(@NotNull String path) throws Exception {
       try {
         Object pathObj = myGetPath.invoke(myDefaultFileSystem, path, ArrayUtil.EMPTY_STRING_ARRAY);

         Map attributes = (Map)myReadAttributes.invoke(null, pathObj, mySchema, myNoFollowLinkOptions);
         boolean isSymbolicLink = (Boolean)attributes.get("isSymbolicLink");
         if (isSymbolicLink) {
           try {
             attributes = (Map)myReadAttributes.invoke(null, pathObj, mySchema, myLinkOptions);
           }
           catch (InvocationTargetException e) {
             final Throwable cause = e.getCause();
             if (cause != null && "java.nio.file.NoSuchFileException".equals(cause.getClass().getName())) {
               return FileAttributes.BROKEN_SYMLINK;
             }
           }
         }

         boolean isDirectory = (Boolean)attributes.get("isDirectory");
         boolean isOther = (Boolean)attributes.get("isOther");
         long size = (Long)attributes.get("size");
         long lastModified = (Long)myToMillis.invoke(attributes.get("lastModifiedTime"));
         if (SystemInfo.isWindows) {
           boolean isHidden = new File(path).getParent() == null ? false : (Boolean)attributes.get("hidden");
           boolean isWritable = !(Boolean)attributes.get("readonly");
           return new FileAttributes(isDirectory, isOther, isSymbolicLink, isHidden, size, lastModified, isWritable);
         }
         else {
           boolean isWritable = new File(path).canWrite();
           return new FileAttributes(isDirectory, isOther, isSymbolicLink, false, size, lastModified, isWritable);
         }
       }
       catch (InvocationTargetException e) {
         final Throwable cause = e.getCause();
         if (cause != null && ("java.nio.file.NoSuchFileException".equals(cause.getClass().getName()) ||
                               "java.nio.file.InvalidPathException".equals(cause.getClass().getName()))) {
           LOG.debug(cause);
           return null;
         }
         throw e;
       }
     }

     @Override
     protected String resolveSymLink(@NotNull final String path) throws Exception {
       if (!new File(path).exists()) return null;
       final Object pathObj = myGetPath.invoke(myDefaultFileSystem, path, ArrayUtil.EMPTY_STRING_ARRAY);
       final Method toRealPath = pathObj.getClass().getMethod("toRealPath", myLinkOptions.getClass());
       toRealPath.setAccessible(true);
       return toRealPath.invoke(pathObj, myLinkOptions).toString();
     }

     @Override
     protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
       if (SystemInfo.isUnix) {
         Object pathObj = myGetPath.invoke(myDefaultFileSystem, source, ArrayUtil.EMPTY_STRING_ARRAY);
         Map attributes = (Map)myReadAttributes.invoke(null, pathObj, "posix:permissions", myLinkOptions);
         if (attributes != null) {
           Object permissions = attributes.get("permissions");
           if (permissions instanceof Collection) {
             mySetAttribute.invoke(null, pathObj, "posix:permissions", permissions, myLinkOptions);
             return true;
           }
         }
       }

       return false;
     }
   }


   private static class IdeaWin32MediatorImpl extends Mediator {
     private IdeaWin32 myInstance = IdeaWin32.getInstance();

     @Override
     protected FileAttributes getAttributes(@NotNull final String path) throws Exception {
       final FileInfo fileInfo = myInstance.getInfo(path);
       return fileInfo != null ? fileInfo.toFileAttributes() : null;
     }

     @Override
     protected String resolveSymLink(@NotNull final String path) throws Exception {
       return myInstance.resolveSymLink(path);
     }
   }


   // thanks to SVNKit for the idea of platform-specific offsets
   private static class JnaUnixMediatorImpl extends Mediator {
     @SuppressWarnings({"OctalInteger", "SpellCheckingInspection"})
     private interface LibC extends Library {
       int S_MASK = 0177777;
       int S_IFLNK = 0120000;  // symbolic link
       int S_IFREG = 0100000;  // regular file
       int S_IFDIR = 0040000;  // directory
       int PERM_MASK = 0777;
       int WRITE_MASK = 0222;
       int W_OK = 2;           // write permission flag for access(2)

       int getuid();
       int getgid();
       int lstat(String path, Pointer stat);
       int stat(String path, Pointer stat);
       int __lxstat64(int ver, String path, Pointer stat);
       int __xstat64(int ver, String path, Pointer stat);
       int chmod(String path, int mode);
       int access(String path, int mode);
     }

     private static final int[] LINUX_32 =  {16, 44, 72, 24, 28};
     private static final int[] LINUX_64 =  {24, 48, 88, 28, 32};
     private static final int[] BSD_32 =    { 8, 48, 32, 12, 16};
     private static final int[] BSD_64 =    { 8, 72, 40, 12, 16};
     private static final int[] SUN_OS_32 = {20, 48, 64, 28, 32};
     private static final int[] SUN_OS_64 = {16, 40, 64, 24, 28};

     private static final int OFF_MODE = 0;
     private static final int OFF_SIZE = 1;
     private static final int OFF_TIME = 2;
     private static final int OFF_UID  = 3;
     private static final int OFF_GID  = 4;

     private final LibC myLibC;
     private final int[] myOffsets;
     private final int myUid;
     private final int myGid;
     private final boolean myCoarseTs = SystemProperties.getBooleanProperty(COARSE_TIMESTAMP, false);

     private JnaUnixMediatorImpl() throws Exception {
       myOffsets = SystemInfo.isLinux ? (SystemInfo.is32Bit ? LINUX_32 : LINUX_64) :
                   SystemInfo.isMac | SystemInfo.isFreeBSD ? (SystemInfo.is32Bit ? BSD_32 : BSD_64) :
                   SystemInfo.isSolaris ? (SystemInfo.is32Bit ? SUN_OS_32 : SUN_OS_64) :
                   null;
       if (myOffsets == null || myOffsets.length != 5) throw new IllegalStateException("Unsupported OS: " + SystemInfo.OS_NAME);

       myLibC = (LibC)Native.loadLibrary("c", LibC.class);
       myUid = myLibC.getuid();
       myGid = myLibC.getgid();
     }

     @Override
     protected FileAttributes getAttributes(@NotNull String path) throws Exception {
       Memory buffer = new Memory(256);
       int res = SystemInfo.isLinux ? myLibC.__lxstat64(0, path, buffer) : myLibC.lstat(path, buffer);
       if (res != 0) return null;

       int mode = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.S_MASK;
       boolean isSymlink = (mode & LibC.S_IFLNK) == LibC.S_IFLNK;
       if (isSymlink) {
         res = SystemInfo.isLinux ? myLibC.__xstat64(0, path, buffer) : myLibC.stat(path, buffer);
         if (res != 0) {
           return FileAttributes.BROKEN_SYMLINK;
         }
         mode = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.S_MASK;
       }

       boolean isDirectory = (mode & LibC.S_IFDIR) == LibC.S_IFDIR;
       boolean isSpecial = !isDirectory && (mode & LibC.S_IFREG) == 0;
       long size = buffer.getLong(myOffsets[OFF_SIZE]);
       long mTime1 = SystemInfo.is32Bit ? buffer.getInt(myOffsets[OFF_TIME]) : buffer.getLong(myOffsets[OFF_TIME]);
       long mTime2 = myCoarseTs ? 0 : SystemInfo.is32Bit ? buffer.getInt(myOffsets[OFF_TIME] + 4) : buffer.getLong(myOffsets[OFF_TIME] + 8);
       long mTime = mTime1 * 1000 + mTime2 / 1000000;

       boolean writable = ownFile(buffer) ? (mode & LibC.WRITE_MASK) != 0 : myLibC.access(path, LibC.W_OK) == 0;

       return new FileAttributes(isDirectory, isSpecial, isSymlink, false, size, mTime, writable);
     }

     @Override
     protected String resolveSymLink(@NotNull final String path) throws Exception {
       try {
         return new File(path).getCanonicalPath();
       }
       catch (IOException e) {
         String message = e.getMessage();
         if (message != null && message.toLowerCase(Locale.US).contains("too many levels of symbolic links")) {
           LOG.debug(e);
           return null;
         }
         throw new IOException("Cannot resolve '" + path + "'", e);
       }
     }

     @Override
     protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
       Memory buffer = new Memory(256);
       int res = SystemInfo.isLinux ? myLibC.__xstat64(0, source, buffer) : myLibC.stat(source, buffer);
       if (res == 0) {
         int permissions = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.PERM_MASK;
         return myLibC.chmod(target, permissions) == 0;
       }

       return false;
     }

     private boolean ownFile(Memory buffer) {
       return buffer.getInt(myOffsets[OFF_UID]) == myUid && buffer.getInt(myOffsets[OFF_GID]) == myGid;
     }
   }


   private static class FallbackMediatorImpl extends Mediator {
     // from java.io.FileSystem
     private static final int BA_REGULAR   = 0x02;
     private static final int BA_DIRECTORY = 0x04;
     private static final int BA_HIDDEN    = 0x08;

     private final Object myFileSystem;
     private final Method myGetBooleanAttributes;

     private FallbackMediatorImpl() {
       Object fileSystem;
       Method getBooleanAttributes;
       try {
         final Class<?> fsClass = Class.forName("java.io.FileSystem");
         final Method getFileSystem = fsClass.getMethod("getFileSystem");
         getFileSystem.setAccessible(true);
         fileSystem = getFileSystem.invoke(null);
         getBooleanAttributes = fsClass.getDeclaredMethod("getBooleanAttributes", File.class);
         getBooleanAttributes.setAccessible(true);
       }
       catch (Throwable t) {
         fileSystem = null;
         getBooleanAttributes = null;
       }
       myFileSystem = fileSystem;
       myGetBooleanAttributes = getBooleanAttributes;
     }

     @Override
     protected FileAttributes getAttributes(@NotNull final String path) throws Exception {
       final File file = new File(path);
       if (myFileSystem != null) {
         final int flags = (Integer)myGetBooleanAttributes.invoke(myFileSystem, file);
         if (flags != 0) {
           final boolean isDirectory = isSet(flags, BA_DIRECTORY);
           final boolean isSpecial = notSet(flags, BA_REGULAR | BA_DIRECTORY);
           final boolean isHidden = isSet(flags, BA_HIDDEN);
           return new FileAttributes(isDirectory, isSpecial, false, isHidden, file.length(), file.lastModified(), file.canWrite());
         }
       }
       else {
         if (file.exists()) {
           final boolean isDirectory = file.isDirectory();
           final boolean isSpecial = !isDirectory && !file.isFile();
           final boolean isHidden = file.isHidden();
           return new FileAttributes(isDirectory, isSpecial, false, isHidden, file.length(), file.lastModified(), file.canWrite());
         }
       }

       return null;
     }

     @Override
     protected String resolveSymLink(@NotNull final String path) throws Exception {
       return new File(path).getCanonicalPath();
     }

     @Override
     protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
       if (SystemInfo.isUnix) {
         File srcFile = new File(source);
         File dstFile = new File(target);
         return dstFile.setWritable(srcFile.canWrite(), true) && dstFile.setExecutable(srcFile.canExecute(), true);
       }

       return false;
     }
   }

   @TestOnly
   static void resetMediator() {
     ourMediator = getMediator();
   }

   @TestOnly
   static String getMediatorName() {
     return ourMediator.getName();
   }
 }
	/*
	* Copyright 2000-2014 JetBrains s.r.o.
	*
	* 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 com.intellij.openapi.util.io;

	import com.intellij.Patches;
	import com.intellij.openapi.diagnostic.Logger;
	import com.intellij.openapi.util.SystemInfo;
	import com.intellij.openapi.util.io.win32.FileInfo;
	import com.intellij.openapi.util.io.win32.IdeaWin32;
	import com.intellij.util.ArrayUtil;
	import com.intellij.util.SystemProperties;
	import com.sun.jna.Library;
	import com.sun.jna.Memory;
	import com.sun.jna.Native;
	import com.sun.jna.Pointer;
	import org.jetbrains.annotations.NotNull;
	import org.jetbrains.annotations.Nullable;
	import org.jetbrains.annotations.TestOnly;

	import java.io.File;
	import java.io.IOException;
	import java.lang.reflect.Array;
	import java.lang.reflect.InvocationTargetException;
	import java.lang.reflect.Method;
	import java.util.*;

	import static com.intellij.util.BitUtil.isSet;
	import static com.intellij.util.BitUtil.notSet;

	/**
	* @version 11.1
	*/
	public class FileSystemUtil {
	static final String FORCE_USE_NIO2_KEY = "idea.io.use.nio2";
	static final String COARSE_TIMESTAMP = "idea.io.coarse.ts";

	private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.util.io.FileSystemUtil");

	private abstract static class Mediator {
	@Nullable
	protected abstract FileAttributes getAttributes(@NotNull String path) throws Exception;

	@Nullable
	protected abstract String resolveSymLink(@NotNull String path) throws Exception;

	protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception { return false; }

	@NotNull
	private String getName() { return getClass().getSimpleName().replace("MediatorImpl", ""); }
	}

	@NotNull
	private static Mediator ourMediator = getMediator();

	private static Mediator getMediator() {
	Throwable error = null;
	final boolean forceUseNio2 = SystemProperties.getBooleanProperty(FORCE_USE_NIO2_KEY, false);

	if (!forceUseNio2) {
	if (SystemInfo.isWindows && IdeaWin32.isAvailable()) {
	try {
	return check(new IdeaWin32MediatorImpl());
	}
	catch (Throwable t) {
	error = t;
	}
	}
	else if (SystemInfo.isLinux \|\| SystemInfo.isMac \|\| SystemInfo.isSolaris \|\| SystemInfo.isFreeBSD) {
	try {
	return check(new JnaUnixMediatorImpl());
	}
	catch (Throwable t) {
	error = t;
	}
	}
	}

	if (SystemInfo.isJavaVersionAtLeast("1.7") && !"1.7.0-ea".equals(SystemInfo.JAVA_VERSION)) {
	try {
	return check(new Nio2MediatorImpl());
	}
	catch (Throwable t) {
	error = t;
	}
	}

	final String message =
	"Failed to load filesystem access layer (" + SystemInfo.OS_NAME + ", " + SystemInfo.JAVA_VERSION + ", " + forceUseNio2 + ")";
	LOG.error(message, error);

	return new FallbackMediatorImpl();
	}

	private static Mediator check(final Mediator mediator) throws Exception {
	final String quickTestPath = SystemInfo.isWindows ? "C:\\" : "/";
	mediator.getAttributes(quickTestPath);
	return mediator;
	}

	private FileSystemUtil() { }

	@Nullable
	public static FileAttributes getAttributes(@NotNull String path) {
	try {
	return ourMediator.getAttributes(path);
	}
	catch (Exception e) {
	LOG.warn(e);
	}
	return null;
	}

	@Nullable
	public static FileAttributes getAttributes(@NotNull File file) {
	return getAttributes(file.getPath());
	}

	public static long lastModified(@NotNull File file) {
	FileAttributes attributes = getAttributes(file);
	return attributes != null ? attributes.lastModified : 0;
	}

	/**
	* Checks if a last element in the path is a symlink.
	*/
	public static boolean isSymLink(@NotNull String path) {
	if (SystemInfo.areSymLinksSupported) {
	final FileAttributes attributes = getAttributes(path);
	return attributes != null && attributes.isSymLink();
	}
	return false;
	}

	/**
	* Checks if a last element in the path is a symlink.
	*/
	public static boolean isSymLink(@NotNull File file) {
	return isSymLink(file.getAbsolutePath());
	}

	@Nullable
	public static String resolveSymLink(@NotNull String path) {
	try {
	final String realPath = ourMediator.resolveSymLink(path);
	if (realPath != null && new File(realPath).exists()) {
	return realPath;
	}
	}
	catch (Exception e) {
	LOG.warn(e);
	}
	return null;
	}

	@Nullable
	public static String resolveSymLink(@NotNull File file) {
	return resolveSymLink(file.getAbsolutePath());
	}

	/** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
	@SuppressWarnings("UnusedDeclaration")
	public static int getPermissions(@NotNull String path) {
	return -1;
	}

	/** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
	@SuppressWarnings("UnusedDeclaration")
	public static int getPermissions(@NotNull File file) {
	return -1;
	}

	/** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
	@SuppressWarnings("UnusedDeclaration")
	public static void setPermissions(@NotNull String path, int permissions) { }

	/** @deprecated use {@link #clonePermissions(String, String)} (to remove in IDEA 14) */
	@SuppressWarnings({"UnusedDeclaration", "deprecation"})
	public static void setPermissions(@NotNull File file, int permissions) { }

	/**
	* Gives the second file permissions of the first one if possible; returns true if succeed.
	* Will do nothing on Windows.
	*/
	public static boolean clonePermissions(@NotNull String source, @NotNull String target) {
	try {
	return ourMediator.clonePermissions(source, target);
	}
	catch (Exception e) {
	LOG.warn(e);
	return false;
	}
	}


	private static class Nio2MediatorImpl extends Mediator {
	private final Object myDefaultFileSystem;
	private final Method myGetPath;
	private final Method myIsSymbolicLink;
	private final Object myLinkOptions;
	private final Object myNoFollowLinkOptions;
	private final Method myReadAttributes;
	private final Method mySetAttribute;
	private final Method myToMillis;
	private final String mySchema;

	private Nio2MediatorImpl() throws Exception {
	//noinspection ConstantConditions
	assert Patches.USE_REFLECTION_TO_ACCESS_JDK7;

	myDefaultFileSystem = Class.forName("java.nio.file.FileSystems").getMethod("getDefault").invoke(null);

	final Class<?> fsClass = Class.forName("java.nio.file.FileSystem");
	myGetPath = fsClass.getMethod("getPath", String.class, String[].class);
	myGetPath.setAccessible(true);

	final Class<?> pathClass = Class.forName("java.nio.file.Path");
	final Class<?> filesClass = Class.forName("java.nio.file.Files");
	myIsSymbolicLink = filesClass.getMethod("isSymbolicLink", pathClass);
	myIsSymbolicLink.setAccessible(true);

	final Class<?> linkOptClass = Class.forName("java.nio.file.LinkOption");
	myLinkOptions = Array.newInstance(linkOptClass, 0);
	myNoFollowLinkOptions = Array.newInstance(linkOptClass, 1);
	Array.set(myNoFollowLinkOptions, 0, linkOptClass.getField("NOFOLLOW_LINKS").get(null));

	final Class<?> linkOptArrClass = myLinkOptions.getClass();
	myReadAttributes = filesClass.getMethod("readAttributes", pathClass, String.class, linkOptArrClass);
	myReadAttributes.setAccessible(true);
	mySetAttribute = filesClass.getMethod("setAttribute", pathClass, String.class, Object.class, linkOptArrClass);
	mySetAttribute.setAccessible(true);

	final Class<?> fileTimeClass = Class.forName("java.nio.file.attribute.FileTime");
	myToMillis = fileTimeClass.getMethod("toMillis");
	myToMillis.setAccessible(true);

	mySchema = SystemInfo.isWindows ? "dos:" : "posix:";
	}

	@Override
	protected FileAttributes getAttributes(@NotNull String path) throws Exception {
	try {
	Object pathObj = myGetPath.invoke(myDefaultFileSystem, path, ArrayUtil.EMPTY_STRING_ARRAY);

	Map attributes = (Map)myReadAttributes.invoke(null, pathObj, mySchema, myNoFollowLinkOptions);
	boolean isSymbolicLink = (Boolean)attributes.get("isSymbolicLink");
	if (isSymbolicLink) {
	try {
	attributes = (Map)myReadAttributes.invoke(null, pathObj, mySchema, myLinkOptions);
	}
	catch (InvocationTargetException e) {
	final Throwable cause = e.getCause();
	if (cause != null && "java.nio.file.NoSuchFileException".equals(cause.getClass().getName())) {
	return FileAttributes.BROKEN_SYMLINK;
	}
	}
	}

	boolean isDirectory = (Boolean)attributes.get("isDirectory");
	boolean isOther = (Boolean)attributes.get("isOther");
	long size = (Long)attributes.get("size");
	long lastModified = (Long)myToMillis.invoke(attributes.get("lastModifiedTime"));
	if (SystemInfo.isWindows) {
	boolean isHidden = new File(path).getParent() == null ? false : (Boolean)attributes.get("hidden");
	boolean isWritable = !(Boolean)attributes.get("readonly");
	return new FileAttributes(isDirectory, isOther, isSymbolicLink, isHidden, size, lastModified, isWritable);
	}
	else {
	boolean isWritable = new File(path).canWrite();
	return new FileAttributes(isDirectory, isOther, isSymbolicLink, false, size, lastModified, isWritable);
	}
	}
	catch (InvocationTargetException e) {
	final Throwable cause = e.getCause();
	if (cause != null && ("java.nio.file.NoSuchFileException".equals(cause.getClass().getName()) \|\|
	"java.nio.file.InvalidPathException".equals(cause.getClass().getName()))) {
	LOG.debug(cause);
	return null;
	}
	throw e;
	}
	}

	@Override
	protected String resolveSymLink(@NotNull final String path) throws Exception {
	if (!new File(path).exists()) return null;
	final Object pathObj = myGetPath.invoke(myDefaultFileSystem, path, ArrayUtil.EMPTY_STRING_ARRAY);
	final Method toRealPath = pathObj.getClass().getMethod("toRealPath", myLinkOptions.getClass());
	toRealPath.setAccessible(true);
	return toRealPath.invoke(pathObj, myLinkOptions).toString();
	}

	@Override
	protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
	if (SystemInfo.isUnix) {
	Object pathObj = myGetPath.invoke(myDefaultFileSystem, source, ArrayUtil.EMPTY_STRING_ARRAY);
	Map attributes = (Map)myReadAttributes.invoke(null, pathObj, "posix:permissions", myLinkOptions);
	if (attributes != null) {
	Object permissions = attributes.get("permissions");
	if (permissions instanceof Collection) {
	mySetAttribute.invoke(null, pathObj, "posix:permissions", permissions, myLinkOptions);
	return true;
	}
	}
	}

	return false;
	}
	}


	private static class IdeaWin32MediatorImpl extends Mediator {
	private IdeaWin32 myInstance = IdeaWin32.getInstance();

	@Override
	protected FileAttributes getAttributes(@NotNull final String path) throws Exception {
	final FileInfo fileInfo = myInstance.getInfo(path);
	return fileInfo != null ? fileInfo.toFileAttributes() : null;
	}

	@Override
	protected String resolveSymLink(@NotNull final String path) throws Exception {
	return myInstance.resolveSymLink(path);
	}
	}


	// thanks to SVNKit for the idea of platform-specific offsets
	private static class JnaUnixMediatorImpl extends Mediator {
	@SuppressWarnings({"OctalInteger", "SpellCheckingInspection"})
	private interface LibC extends Library {
	int S_MASK = 0177777;
	int S_IFLNK = 0120000; // symbolic link
	int S_IFREG = 0100000; // regular file
	int S_IFDIR = 0040000; // directory
	int PERM_MASK = 0777;
	int WRITE_MASK = 0222;
	int W_OK = 2; // write permission flag for access(2)

	int getuid();
	int getgid();
	int lstat(String path, Pointer stat);
	int stat(String path, Pointer stat);
	int __lxstat64(int ver, String path, Pointer stat);
	int __xstat64(int ver, String path, Pointer stat);
	int chmod(String path, int mode);
	int access(String path, int mode);
	}

	private static final int[] LINUX_32 = {16, 44, 72, 24, 28};
	private static final int[] LINUX_64 = {24, 48, 88, 28, 32};
	private static final int[] BSD_32 = { 8, 48, 32, 12, 16};
	private static final int[] BSD_64 = { 8, 72, 40, 12, 16};
	private static final int[] SUN_OS_32 = {20, 48, 64, 28, 32};
	private static final int[] SUN_OS_64 = {16, 40, 64, 24, 28};

	private static final int OFF_MODE = 0;
	private static final int OFF_SIZE = 1;
	private static final int OFF_TIME = 2;
	private static final int OFF_UID = 3;
	private static final int OFF_GID = 4;

	private final LibC myLibC;
	private final int[] myOffsets;
	private final int myUid;
	private final int myGid;
	private final boolean myCoarseTs = SystemProperties.getBooleanProperty(COARSE_TIMESTAMP, false);

	private JnaUnixMediatorImpl() throws Exception {
	myOffsets = SystemInfo.isLinux ? (SystemInfo.is32Bit ? LINUX_32 : LINUX_64) :
	SystemInfo.isMac \| SystemInfo.isFreeBSD ? (SystemInfo.is32Bit ? BSD_32 : BSD_64) :
	SystemInfo.isSolaris ? (SystemInfo.is32Bit ? SUN_OS_32 : SUN_OS_64) :
	null;
	if (myOffsets == null \|\| myOffsets.length != 5) throw new IllegalStateException("Unsupported OS: " + SystemInfo.OS_NAME);

	myLibC = (LibC)Native.loadLibrary("c", LibC.class);
	myUid = myLibC.getuid();
	myGid = myLibC.getgid();
	}

	@Override
	protected FileAttributes getAttributes(@NotNull String path) throws Exception {
	Memory buffer = new Memory(256);
	int res = SystemInfo.isLinux ? myLibC.__lxstat64(0, path, buffer) : myLibC.lstat(path, buffer);
	if (res != 0) return null;

	int mode = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.S_MASK;
	boolean isSymlink = (mode & LibC.S_IFLNK) == LibC.S_IFLNK;
	if (isSymlink) {
	res = SystemInfo.isLinux ? myLibC.__xstat64(0, path, buffer) : myLibC.stat(path, buffer);
	if (res != 0) {
	return FileAttributes.BROKEN_SYMLINK;
	}
	mode = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.S_MASK;
	}

	boolean isDirectory = (mode & LibC.S_IFDIR) == LibC.S_IFDIR;
	boolean isSpecial = !isDirectory && (mode & LibC.S_IFREG) == 0;
	long size = buffer.getLong(myOffsets[OFF_SIZE]);
	long mTime1 = SystemInfo.is32Bit ? buffer.getInt(myOffsets[OFF_TIME]) : buffer.getLong(myOffsets[OFF_TIME]);
	long mTime2 = myCoarseTs ? 0 : SystemInfo.is32Bit ? buffer.getInt(myOffsets[OFF_TIME] + 4) : buffer.getLong(myOffsets[OFF_TIME] + 8);
	long mTime = mTime1 * 1000 + mTime2 / 1000000;

	boolean writable = ownFile(buffer) ? (mode & LibC.WRITE_MASK) != 0 : myLibC.access(path, LibC.W_OK) == 0;

	return new FileAttributes(isDirectory, isSpecial, isSymlink, false, size, mTime, writable);
	}

	@Override
	protected String resolveSymLink(@NotNull final String path) throws Exception {
	try {
	return new File(path).getCanonicalPath();
	}
	catch (IOException e) {
	String message = e.getMessage();
	if (message != null && message.toLowerCase(Locale.US).contains("too many levels of symbolic links")) {
	LOG.debug(e);
	return null;
	}
	throw new IOException("Cannot resolve '" + path + "'", e);
	}
	}

	@Override
	protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
	Memory buffer = new Memory(256);
	int res = SystemInfo.isLinux ? myLibC.__xstat64(0, source, buffer) : myLibC.stat(source, buffer);
	if (res == 0) {
	int permissions = (SystemInfo.isLinux ? buffer.getInt(myOffsets[OFF_MODE]) : buffer.getShort(myOffsets[OFF_MODE])) & LibC.PERM_MASK;
	return myLibC.chmod(target, permissions) == 0;
	}

	return false;
	}

	private boolean ownFile(Memory buffer) {
	return buffer.getInt(myOffsets[OFF_UID]) == myUid && buffer.getInt(myOffsets[OFF_GID]) == myGid;
	}
	}


	private static class FallbackMediatorImpl extends Mediator {
	// from java.io.FileSystem
	private static final int BA_REGULAR = 0x02;
	private static final int BA_DIRECTORY = 0x04;
	private static final int BA_HIDDEN = 0x08;

	private final Object myFileSystem;
	private final Method myGetBooleanAttributes;

	private FallbackMediatorImpl() {
	Object fileSystem;
	Method getBooleanAttributes;
	try {
	final Class<?> fsClass = Class.forName("java.io.FileSystem");
	final Method getFileSystem = fsClass.getMethod("getFileSystem");
	getFileSystem.setAccessible(true);
	fileSystem = getFileSystem.invoke(null);
	getBooleanAttributes = fsClass.getDeclaredMethod("getBooleanAttributes", File.class);
	getBooleanAttributes.setAccessible(true);
	}
	catch (Throwable t) {
	fileSystem = null;
	getBooleanAttributes = null;
	}
	myFileSystem = fileSystem;
	myGetBooleanAttributes = getBooleanAttributes;
	}

	@Override
	protected FileAttributes getAttributes(@NotNull final String path) throws Exception {
	final File file = new File(path);
	if (myFileSystem != null) {
	final int flags = (Integer)myGetBooleanAttributes.invoke(myFileSystem, file);
	if (flags != 0) {
	final boolean isDirectory = isSet(flags, BA_DIRECTORY);
	final boolean isSpecial = notSet(flags, BA_REGULAR \| BA_DIRECTORY);
	final boolean isHidden = isSet(flags, BA_HIDDEN);
	return new FileAttributes(isDirectory, isSpecial, false, isHidden, file.length(), file.lastModified(), file.canWrite());
	}
	}
	else {
	if (file.exists()) {
	final boolean isDirectory = file.isDirectory();
	final boolean isSpecial = !isDirectory && !file.isFile();
	final boolean isHidden = file.isHidden();
	return new FileAttributes(isDirectory, isSpecial, false, isHidden, file.length(), file.lastModified(), file.canWrite());
	}
	}

	return null;
	}

	@Override
	protected String resolveSymLink(@NotNull final String path) throws Exception {
	return new File(path).getCanonicalPath();
	}

	@Override
	protected boolean clonePermissions(@NotNull String source, @NotNull String target) throws Exception {
	if (SystemInfo.isUnix) {
	File srcFile = new File(source);
	File dstFile = new File(target);
	return dstFile.setWritable(srcFile.canWrite(), true) && dstFile.setExecutable(srcFile.canExecute(), true);
	}

	return false;
	}
	}

	@TestOnly
	static void resetMediator() {
	ourMediator = getMediator();
	}

	@TestOnly
	static String getMediatorName() {
	return ourMediator.getName();
	}
	}