HADOOP-9413. Add common utils for File#setReadable/Writable/Executable & File#canRead/Write/Execute that work cross-platform. Contributed by Ivan Mitic.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1477376 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -532,6 +532,9 @@ Trunk (Unreleased)
     HADOOP-9524. Fix ShellCommandFencer to work on Windows.
     (Arpit Agarwal via suresh)
 
+    HADOOP-9413. Add common utils for File#setReadable/Writable/Executable &
+    File#canRead/Write/Execute that work cross-platform. (Ivan Mitic via suresh)
+    
 Release 2.0.5-beta - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileUtil.java

@@ -44,7 +44,6 @@ import org.apache.hadoop.io.nativeio.NativeIO;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.util.Shell.ShellCommandExecutor;
-
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
@@ -148,9 +147,9 @@ public class FileUtil {
    * Pure-Java implementation of "chmod +rwx f".
    */
   private static void grantPermissions(final File f) {
-      f.setExecutable(true);
+      FileUtil.setExecutable(f, true);
-      f.setReadable(true);
+      FileUtil.setReadable(f, true);
-      f.setWritable(true);
+      FileUtil.setWritable(f, true);
   }
 
   private static boolean deleteImpl(final File f, final boolean doLog) {
@@ -851,6 +850,129 @@ public class FileUtil {
     execCommand(file, cmd);
   }
 
+  /**
+   * Platform independent implementation for {@link File#setReadable(boolean)}
+   * File#setReadable does not work as expected on Windows.
+   * @param f input file
+   * @param readable
+   * @return true on success, false otherwise
+   */
+  public static boolean setReadable(File f, boolean readable) {
+    if (Shell.WINDOWS) {
+      try {
+        String permission = readable ? "u+r" : "u-r";
+        FileUtil.chmod(f.getCanonicalPath(), permission, false);
+        return true;
+      } catch (IOException ex) {
+        return false;
+      }
+    } else {
+      return f.setReadable(readable);
+    }
+  }
+
+  /**
+   * Platform independent implementation for {@link File#setWritable(boolean)}
+   * File#setWritable does not work as expected on Windows.
+   * @param f input file
+   * @param writable
+   * @return true on success, false otherwise
+   */
+  public static boolean setWritable(File f, boolean writable) {
+    if (Shell.WINDOWS) {
+      try {
+        String permission = writable ? "u+w" : "u-w";
+        FileUtil.chmod(f.getCanonicalPath(), permission, false);
+        return true;
+      } catch (IOException ex) {
+        return false;
+      }
+    } else {
+      return f.setWritable(writable);
+    }
+  }
+
+  /**
+   * Platform independent implementation for {@link File#setExecutable(boolean)}
+   * File#setExecutable does not work as expected on Windows.
+   * Note: revoking execute permission on folders does not have the same
+   * behavior on Windows as on Unix platforms. Creating, deleting or renaming
+   * a file within that folder will still succeed on Windows.
+   * @param f input file
+   * @param executable
+   * @return true on success, false otherwise
+   */
+  public static boolean setExecutable(File f, boolean executable) {
+    if (Shell.WINDOWS) {
+      try {
+        String permission = executable ? "u+x" : "u-x";
+        FileUtil.chmod(f.getCanonicalPath(), permission, false);
+        return true;
+      } catch (IOException ex) {
+        return false;
+      }
+    } else {
+      return f.setExecutable(executable);
+    }
+  }
+
+  /**
+   * Platform independent implementation for {@link File#canRead()}
+   * @param f input file
+   * @return On Unix, same as {@link File#canRead()}
+   *         On Windows, true if process has read access on the path
+   */
+  public static boolean canRead(File f) {
+    if (Shell.WINDOWS) {
+      try {
+        return NativeIO.Windows.access(f.getCanonicalPath(),
+            NativeIO.Windows.AccessRight.ACCESS_READ);
+      } catch (IOException e) {
+        return false;
+      }
+    } else {
+      return f.canRead();
+    }
+  }
+
+  /**
+   * Platform independent implementation for {@link File#canWrite()}
+   * @param f input file
+   * @return On Unix, same as {@link File#canWrite()}
+   *         On Windows, true if process has write access on the path
+   */
+  public static boolean canWrite(File f) {
+    if (Shell.WINDOWS) {
+      try {
+        return NativeIO.Windows.access(f.getCanonicalPath(),
+            NativeIO.Windows.AccessRight.ACCESS_WRITE);
+      } catch (IOException e) {
+        return false;
+      }
+    } else {
+      return f.canWrite();
+    }
+  }
+
+  /**
+   * Platform independent implementation for {@link File#canExecute()}
+   * @param f input file
+   * @return On Unix, same as {@link File#canExecute()}
+   *         On Windows, true if process has execute access on the path
+   */
+  public static boolean canExecute(File f) {
+    if (Shell.WINDOWS) {
+      try {
+        return NativeIO.Windows.access(f.getCanonicalPath(),
+            NativeIO.Windows.AccessRight.ACCESS_EXECUTE);
+      } catch (IOException e) {
+        return false;
+      }
+    } else {
+      return f.canExecute();
+    }
+  }
+
   /**
    * Set permissions to the required value. Uses the java primitives instead
    * of forking if group == other.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/LocalFileSystem.java

@@ -103,7 +103,8 @@ public class LocalFileSystem extends ChecksumFileSystem {
       String device = new DF(f, getConf()).getMount();
       File parent = f.getParentFile();
       File dir = null;
-      while (parent!=null && parent.canWrite() && parent.toString().startsWith(device)) {
+      while (parent != null && FileUtil.canWrite(parent) &&
+          parent.toString().startsWith(device)) {
         dir = parent;
         parent = parent.getParentFile();
       }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/nativeio/NativeIO.java

@@ -356,6 +356,43 @@ public class NativeIO {
     /** Windows only methods used for getOwner() implementation */
     private static native String getOwner(FileDescriptor fd) throws IOException;
 
+    /** Supported list of Windows access right flags */
+    public static enum AccessRight {
+      ACCESS_READ (0x0001),      // FILE_READ_DATA
+      ACCESS_WRITE (0x0002),     // FILE_WRITE_DATA
+      ACCESS_EXECUTE (0x0020);   // FILE_EXECUTE
+
+      private final int accessRight;
+      AccessRight(int access) {
+        accessRight = access;
+      }
+
+      public int accessRight() {
+        return accessRight;
+      }
+    };
+
+    /** Windows only method used to check if the current process has requested
+     *  access rights on the given path. */
+    private static native boolean access0(String path, int requestedAccess);
+
+    /**
+     * Checks whether the current process has desired access rights on
+     * the given path.
+     * 
+     * Longer term this native function can be substituted with JDK7
+     * function Files#isReadable, isWritable, isExecutable.
+     *
+     * @param path input path
+     * @param desiredAccess ACCESS_READ, ACCESS_WRITE or ACCESS_EXECUTE
+     * @return true if access is allowed
+     * @throws IOException I/O exception on error
+     */
+    public static boolean access(String path, AccessRight desiredAccess)
+        throws IOException {
+      return access0(path, desiredAccess.accessRight());
+    }
+
     static {
       if (NativeCodeLoader.isNativeCodeLoaded()) {
         try {

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/DiskChecker.java

@@ -23,6 +23,7 @@ import java.io.IOException;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
+import org.apache.hadoop.fs.FileUtil;
 import org.apache.hadoop.fs.LocalFileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
@@ -160,12 +161,8 @@ public class DiskChecker {
                                    + dir.toString());
     }
 
-    if (Shell.WINDOWS) {
-      checkAccessByFileSystemInteraction(dir);
-    } else {
     checkAccessByFileMethods(dir);
   }
-  }
 
   /**
    * Checks that the current running process can read, write, and execute the
@@ -177,68 +174,19 @@ public class DiskChecker {
    */
   private static void checkAccessByFileMethods(File dir)
       throws DiskErrorException {
-    if (!dir.canRead()) {
+    if (!FileUtil.canRead(dir)) {
       throw new DiskErrorException("Directory is not readable: "
                                    + dir.toString());
     }
 
-    if (!dir.canWrite()) {
+    if (!FileUtil.canWrite(dir)) {
       throw new DiskErrorException("Directory is not writable: "
                                    + dir.toString());
     }
 
-    if (!dir.canExecute()) {
+    if (!FileUtil.canExecute(dir)) {
       throw new DiskErrorException("Directory is not executable: "
                                    + dir.toString());
     }
   }
-
-  /**
-   * Checks that the current running process can read, write, and execute the
-   * given directory by attempting each of those operations on the file system.
-   * This method contains several workarounds to known JVM bugs that cause
-   * File.canRead, File.canWrite, and File.canExecute to return incorrect results
-   * on Windows with NTFS ACLs.  See:
-   * http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6203387
-   * These bugs are supposed to be fixed in JDK7.
-   * 
-   * @param dir File to check
-   * @throws DiskErrorException if dir is not readable, not writable, or not
-   *   executable
-   */
-  private static void checkAccessByFileSystemInteraction(File dir)
-      throws DiskErrorException {
-    // Make sure we can read the directory by listing it.
-    if (dir.list() == null) {
-      throw new DiskErrorException("Directory is not readable: "
-                                   + dir.toString());
-    }
-
-    // Make sure we can write to the directory by creating a temp file in it.
-    try {
-      File tempFile = File.createTempFile("checkDirAccess", null, dir);
-      if (!tempFile.delete()) {
-        throw new DiskErrorException("Directory is not writable: "
-                                     + dir.toString());
-      }
-    } catch (IOException e) {
-      throw new DiskErrorException("Directory is not writable: "
-                                   + dir.toString(), e);
-    }
-
-    // Make sure the directory is executable by trying to cd into it.  This
-    // launches a separate process.  It does not change the working directory of
-    // the current process.
-    try {
-      String[] cdCmd = new String[] { "cmd", "/C", "cd",
-          dir.getAbsolutePath() };
-      Shell.execCommand(null, cdCmd, SHELL_TIMEOUT);
-    } catch (Shell.ExitCodeException e) {
-      throw new DiskErrorException("Directory is not executable: "
-                                   + dir.toString(), e);
-    } catch (IOException e) {
-      throw new DiskErrorException("Directory is not executable: "
-                                   + dir.toString(), e);
-    }
-  }
 }

hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/nativeio/NativeIO.c

@@ -812,6 +812,42 @@ cleanup:
 #endif
 }
 
+/*
+ * Class:     org_apache_hadoop_io_nativeio_NativeIO_Windows
+ * Method:    access0
+ * Signature: (Ljava/lang/String;I)Z
+ */
+JNIEXPORT jboolean JNICALL Java_org_apache_hadoop_io_nativeio_NativeIO_00024Windows_access0
+  (JNIEnv *env, jclass clazz, jstring jpath, jint jaccess)
+{
+#ifdef UNIX
+  THROW(env, "java/io/IOException",
+    "The function access0(path, access) is not supported on Unix");
+  return NULL;
+#endif
+
+#ifdef WINDOWS
+  LPCWSTR path = NULL;
+  DWORD dwRtnCode = ERROR_SUCCESS;
+  ACCESS_MASK access = (ACCESS_MASK)jaccess;
+  BOOL allowed = FALSE;
+
+  path = (LPCWSTR) (*env)->GetStringChars(env, jpath, NULL);
+  if (!path) goto cleanup; // exception was thrown
+
+  dwRtnCode = CheckAccessForCurrentUser(path, access, &allowed);
+  if (dwRtnCode != ERROR_SUCCESS) {
+    throw_ioe(env, dwRtnCode);
+    goto cleanup;
+  }
+
+cleanup:
+  if (path) (*env)->ReleaseStringChars(env, jpath, path);
+
+  return (jboolean)allowed;
+#endif
+}
+
 JNIEXPORT void JNICALL 
 Java_org_apache_hadoop_io_nativeio_NativeIO_renameTo0(JNIEnv *env, 
 jclass clazz, jstring jsrc, jstring jdst)

hadoop-common-project/hadoop-common/src/main/winutils/include/winutils.h

@@ -110,6 +110,11 @@ void SystemInfoUsage();
 DWORD GetFileInformationByName(__in LPCWSTR pathName,  __in BOOL followLink,
   __out LPBY_HANDLE_FILE_INFORMATION lpFileInformation);
 
+DWORD CheckAccessForCurrentUser(
+  __in PCWSTR pathName,
+  __in ACCESS_MASK requestedAccess,
+  __out BOOL *allowed);
+
 DWORD ConvertToLongPath(__in PCWSTR path, __deref_out PWSTR *newPath);
 
 DWORD GetSidFromAcctNameW(__in PCWSTR acctName, __out PSID* ppSid);

hadoop-common-project/hadoop-common/src/main/winutils/libwinutils.c

@@ -567,7 +567,7 @@ static DWORD GetEffectiveRightsForSid(PSECURITY_DESCRIPTOR psd,
   PSID pSid,
   PACCESS_MASK pAccessRights)
 {
-  AUTHZ_RESOURCE_MANAGER_HANDLE hManager;
+  AUTHZ_RESOURCE_MANAGER_HANDLE hManager = NULL;
   LUID unusedId = { 0 };
   AUTHZ_CLIENT_CONTEXT_HANDLE hAuthzClientContext = NULL;
   DWORD dwRtnCode = ERROR_SUCCESS;
@@ -581,6 +581,10 @@ static DWORD GetEffectiveRightsForSid(PSECURITY_DESCRIPTOR psd,
     return GetLastError();
   }
 
+  // Pass AUTHZ_SKIP_TOKEN_GROUPS to the function to avoid querying user group
+  // information for access check. This allows us to model POSIX permissions
+  // on Windows, where a user can have less permissions than a group it
+  // belongs to.
   if(!AuthzInitializeContextFromSid(AUTHZ_SKIP_TOKEN_GROUPS,
     pSid, hManager, NULL, unusedId, NULL, &hAuthzClientContext))
   {
@@ -594,16 +598,115 @@ static DWORD GetEffectiveRightsForSid(PSECURITY_DESCRIPTOR psd,
     ret = dwRtnCode;
     goto GetEffectiveRightsForSidEnd;
   }
-  if (!AuthzFreeContext(hAuthzClientContext))
-  {
-    ret = GetLastError();
-    goto GetEffectiveRightsForSidEnd;
-  }
 
 GetEffectiveRightsForSidEnd:
+  if (hManager != NULL)
+  {
+    (void)AuthzFreeResourceManager(hManager);
+  }
+  if (hAuthzClientContext != NULL)
+  {
+    (void)AuthzFreeContext(hAuthzClientContext);
+  }
+
   return ret;
 }
 
+//----------------------------------------------------------------------------
+// Function: CheckAccessForCurrentUser
+//
+// Description:
+//   Checks if the current process has the requested access rights on the given
+//   path. Based on the following MSDN article:
+//   http://msdn.microsoft.com/en-us/library/windows/desktop/ff394771(v=vs.85).aspx
+//
+// Returns:
+//   ERROR_SUCCESS: on success
+//
+DWORD CheckAccessForCurrentUser(
+  __in PCWSTR pathName,
+  __in ACCESS_MASK requestedAccess,
+  __out BOOL *allowed)
+{
+  DWORD dwRtnCode = ERROR_SUCCESS;
+
+  LPWSTR longPathName = NULL;
+  HANDLE hProcessToken = NULL;
+  PSECURITY_DESCRIPTOR pSd = NULL;
+
+  AUTHZ_RESOURCE_MANAGER_HANDLE hManager = NULL;
+  AUTHZ_CLIENT_CONTEXT_HANDLE hAuthzClientContext = NULL;
+  LUID Luid = {0, 0};
+
+  ACCESS_MASK currentUserAccessRights = 0;
+
+  // Prepend the long path prefix if needed
+  dwRtnCode = ConvertToLongPath(pathName, &longPathName);
+  if (dwRtnCode != ERROR_SUCCESS)
+  {
+    goto CheckAccessEnd;
+  }
+
+  // Get SD of the given path. OWNER and DACL security info must be
+  // requested, otherwise, AuthzAccessCheck fails with invalid parameter
+  // error.
+  dwRtnCode = GetNamedSecurityInfo(longPathName, SE_FILE_OBJECT,
+    OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION |
+    DACL_SECURITY_INFORMATION,
+    NULL, NULL, NULL, NULL, &pSd);
+  if (dwRtnCode != ERROR_SUCCESS)
+  {
+    goto CheckAccessEnd;
+  }
+
+  // Get current process token
+  if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hProcessToken))
+  {
+    dwRtnCode = GetLastError();
+    goto CheckAccessEnd;
+  }
+
+  if (!AuthzInitializeResourceManager(AUTHZ_RM_FLAG_NO_AUDIT, NULL, NULL,
+    NULL, NULL, &hManager))
+  {
+    dwRtnCode = GetLastError();
+    goto CheckAccessEnd;
+  }
+
+  if(!AuthzInitializeContextFromToken(0, hProcessToken, hManager, NULL,
+    Luid, NULL, &hAuthzClientContext))
+  {
+    dwRtnCode = GetLastError();
+    goto CheckAccessEnd;
+  }
+
+  dwRtnCode = GetAccess(hAuthzClientContext, pSd, &currentUserAccessRights);
+  if (dwRtnCode != ERROR_SUCCESS)
+  {
+    goto CheckAccessEnd;
+  }
+
+  *allowed = ((currentUserAccessRights & requestedAccess) == requestedAccess);
+
+CheckAccessEnd:
+  LocalFree(longPathName);
+  LocalFree(pSd);
+  if (hProcessToken != NULL)
+  {
+    CloseHandle(hProcessToken);
+  }
+  if (hManager != NULL)
+  {
+    (void)AuthzFreeResourceManager(hManager);
+  }
+  if (hAuthzClientContext != NULL)
+  {
+    (void)AuthzFreeContext(hAuthzClientContext);
+  }
+
+  return dwRtnCode;
+}
+
 //----------------------------------------------------------------------------
 // Function: FindFileOwnerAndPermission
 //

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestFileUtil.java

@@ -353,15 +353,15 @@ public class TestFileUtil {
   }
   
   private static void grantPermissions(final File f) {
-    f.setReadable(true);
+    FileUtil.setReadable(f, true);
-    f.setWritable(true);
+    FileUtil.setWritable(f, true);
-    f.setExecutable(true);
+    FileUtil.setExecutable(f, true);
   }
   
   private static void revokePermissions(final File f) {
-     f.setWritable(false);
+     FileUtil.setWritable(f, false);
-     f.setExecutable(false);
+     FileUtil.setExecutable(f, false);
-     f.setReadable(false);
+     FileUtil.setReadable(f, false);
   }
   
   // Validates the return value.

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestLocalFileSystem.java

@@ -59,7 +59,7 @@ public class TestLocalFileSystem {
   
   @After
   public void after() throws IOException {
-    base.setWritable(true);
+    FileUtil.setWritable(base, true);
     FileUtil.fullyDelete(base);
     assertTrue(!base.exists());
   }
@@ -298,7 +298,7 @@ public class TestLocalFileSystem {
     final File dir1 = new File(base, "dir1");
     final File dir2 = new File(dir1, "dir2");
     dir2.mkdirs();
-    assertTrue(dir2.exists() && dir2.canWrite());
+    assertTrue(dir2.exists() && FileUtil.canWrite(dir2));
     
     final String dataFileName = "corruptedData";
     final Path dataPath = new Path(new File(dir2, dataFileName).toURI());
@@ -321,7 +321,7 @@ public class TestLocalFileSystem {
     // this is a hack to force the #reportChecksumFailure() method to stop
     // climbing up at the 'base' directory and use 'dir1/bad_files' as the 
     // corrupted files storage:
-    base.setWritable(false);
+    FileUtil.setWritable(base, false);
     
     FSDataInputStream dataFsdis = fileSys.open(dataPath);
     FSDataInputStream checksumFsdis = fileSys.open(checksumPath);

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/io/nativeio/TestNativeIO.java

@@ -240,6 +240,44 @@ public class TestNativeIO {
 
   }
 
+  /** Validate access checks on Windows */
+  @Test (timeout = 30000)
+  public void testAccess() throws Exception {
+    if (!Path.WINDOWS) {
+      return;
+    }
+
+    File testFile = new File(TEST_DIR, "testfileaccess");
+    assertTrue(testFile.createNewFile());
+
+    // Validate ACCESS_READ
+    FileUtil.setReadable(testFile, false);
+    assertFalse(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_READ));
+
+    FileUtil.setReadable(testFile, true);
+    assertTrue(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_READ));
+
+    // Validate ACCESS_WRITE
+    FileUtil.setWritable(testFile, false);
+    assertFalse(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_WRITE));
+
+    FileUtil.setWritable(testFile, true);
+    assertTrue(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_WRITE));
+
+    // Validate ACCESS_EXECUTE
+    FileUtil.setExecutable(testFile, false);
+    assertFalse(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_EXECUTE));
+
+    FileUtil.setExecutable(testFile, true);
+    assertTrue(NativeIO.Windows.access(testFile.getAbsolutePath(),
+        NativeIO.Windows.AccessRight.ACCESS_EXECUTE));
+  }
+
   @Test (timeout = 30000)
   public void testOpenMissingWithoutCreate() throws Exception {
     if (Path.WINDOWS) {

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/net/unix/TemporarySocketDirectory.java

@@ -23,6 +23,7 @@ import java.io.IOException;
 import java.util.Random;
 
 import org.apache.commons.io.FileUtils;
+import org.apache.hadoop.fs.FileUtil;
 
 /**
  * Create a temporary directory in which sockets can be created.
@@ -37,7 +38,7 @@ public class TemporarySocketDirectory implements Closeable {
     dir = new File(tmp, "socks." + (System.currentTimeMillis() +
         "." + (new Random().nextInt())));
     dir.mkdirs();
-    dir.setWritable(true, true);
+    FileUtil.setWritable(dir, true);
   }
 
   public File getDir() {

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestShell.java

@@ -28,6 +28,8 @@ import java.lang.management.ManagementFactory;
 import java.lang.management.ThreadInfo;
 import java.lang.management.ThreadMXBean;
 
+import org.apache.hadoop.fs.FileUtil;
+
 public class TestShell extends TestCase {
 
   private static class Command extends Shell {
@@ -92,7 +94,7 @@ public class TestShell extends TestCase {
     PrintWriter writer = new PrintWriter(new FileOutputStream(shellFile));
     writer.println(timeoutCommand);
     writer.close();
-    shellFile.setExecutable(true);
+    FileUtil.setExecutable(shellFile, true);
     Shell.ShellCommandExecutor shexc 
     = new Shell.ShellCommandExecutor(new String[]{shellFile.getAbsolutePath()},
                                       null, null, 100);