Added umount command and unmount() API

Co-authored-by: LSantha <LSantha@users.noreply.github.com>

Author: opencode-agent[bot]

fs/descriptors/org.jnode.fs.command.xml

@@ -43,6 +43,7 @@
     <alias name="eject" class="org.jnode.fs.command.EjectCommand"/>
     <alias name="mount" class="org.jnode.fs.command.MountCommand"/>
     <alias name="sync" class="org.jnode.fs.command.SyncCommand"/>
+    <alias name="umount" class="org.jnode.fs.command.UnmountCommand"/>
   </extension>
 
   <extension point="org.jnode.shell.syntaxes">
@@ -61,11 +62,16 @@
       </sequence>
     </syntax>
     <syntax alias="sync">
-      <empty description="Flush all mounted filesystems to disk"/>
+      <empty description="Flush all mounted filesystems"/>
       <sequence description="Flush the filesystem at a specific path">
         <argument argLabel="path" description="the path of the filesystem to flush"/>
       </sequence>
     </syntax>
+    <syntax alias="umount">
+      <sequence description="Unmount the filesystem at the given path">
+        <argument argLabel="directory"/>
+      </sequence>
+    </syntax>
   </extension>
 
   <extension point="org.jnode.security.permissions">

fs/src/commands/org/jnode/fs/command/UnmountCommand.java

@@ -0,0 +1,69 @@
+/*
+ * $Id$
+ *
+ * Copyright (C) 2003-2015 JNode.org
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; If not, write to the Free Software Foundation, Inc., 
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+ 
+package org.jnode.fs.command;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import org.jnode.fs.service.FileSystemService;
+import org.jnode.naming.InitialNaming;
+import org.jnode.shell.AbstractCommand;
+import org.jnode.shell.syntax.Argument;
+import org.jnode.shell.syntax.FileArgument;
+
+/**
+ * Unmount a filesystem.
+ */
+public class UnmountCommand extends AbstractCommand {
+
+    private final FileArgument argDir =
+        new FileArgument("directory", Argument.MANDATORY,
+            "the mount point to unmount");
+
+    public UnmountCommand() {
+        super("Unmount a filesystem");
+        registerArguments(argDir);
+    }
+
+    public static void main(String[] args) throws Exception {
+        new UnmountCommand().execute(args);
+    }
+
+    public void execute() throws Exception {
+        FileSystemService fss = InitialNaming.lookup(FileSystemService.NAME);
+        PrintWriter out = getOutput().getPrintWriter();
+        PrintWriter err = getError().getPrintWriter();
+        String path = argDir.getValue().getCanonicalPath();
+
+        if (!fss.isMount(path)) {
+            err.println("Not a mount point: " + path);
+            err.println("Use 'mount' to list mounted filesystems.");
+            exit(1);
+        }
+
+        try {
+            fss.unmount(path);
+            out.println("Unmounted " + path);
+        } catch (IOException ex) {
+            err.println("Failed to unmount " + path + ": " + ex.getMessage());
+            exit(1);
+        }
+    }
+}

fs/src/fs/org/jnode/fs/service/FileSystemService.java

@@ -115,6 +115,16 @@ public <T extends FileSystemType<?>> T getFileSystemType(Class<T> name)
      */
     public boolean isMount(String fullPath);
 
+    /**
+     * Unmount the filesystem at the given path.
+     * Flushes the filesystem, closes it, and removes the mount point.
+     *
+     * @param fullPath the mount point path
+     * @throws IOException if flush or close fails
+     * @throws IllegalArgumentException if path is not a mount point
+     */
+    public void unmount(String fullPath) throws IOException;
+
     /**
      * Gets the filesystem API.
      */

fs/src/fs/org/jnode/fs/service/def/FileSystemAPIImpl.java

@@ -37,6 +37,7 @@
 import org.jnode.fs.FSDirectory;
 import org.jnode.fs.FSEntry;
 import org.jnode.fs.FileSystem;
+import org.jnode.fs.spi.AbstractFileSystem;
 import org.jnode.java.io.VMFileHandle;
 
 /**
@@ -460,8 +461,37 @@ void mount(String fullPath, FileSystem<?> fs, String fsPath) throws IOException
             fullPath = File.separatorChar + fullPath;
         }
 
-        mountPoints.put(fullPath, fs); // TODO handle removal (+ add unmount
-                                        // method) of filesystems
+        mountPoints.put(fullPath, fs);
+    }
+
+    /**
+     * Unmount the filesystem at the given path.
+     * Flushes the filesystem, closes it, and removes the mount point.
+     *
+     * @param fullPath the mount point path
+     * @throws IOException if flush or close fails
+     * @throws IllegalArgumentException if path is not a mount point
+     */
+    void unmount(String fullPath) throws IOException {
+        if (fullPath.charAt(0) != File.separatorChar) {
+            fullPath = File.separatorChar + fullPath;
+        }
+
+        FileSystem<?> fs = mountPoints.remove(fullPath);
+        if (fs == null) {
+            throw new IllegalArgumentException("Not a mount point: " + fullPath);
+        }
+
+        try {
+            if (!fs.isReadOnly() && fs instanceof AbstractFileSystem) {
+                ((AbstractFileSystem<?>) fs).flush();
+            }
+            vfs.unregisterFileSystem(fs.getDevice());
+            fs.close();
+        } catch (IOException ex) {
+            mountPoints.put(fullPath, fs);
+            throw ex;
+        }
     }
 
     /**

fs/src/fs/org/jnode/fs/service/def/FileSystemPlugin.java

@@ -147,6 +147,18 @@ public void mount(String fullPath, FileSystem<?> fs, String fsPath) throws IOExc
         api.mount(VMFile.getNormalizedPath(fullPath), fs, fsPath);
     }
 
+    /**
+     * Unmount the filesystem at the given path.
+     * Flushes the filesystem, closes it, and removes the mount point.
+     *
+     * @param fullPath the mount point path
+     * @throws IOException if flush or close fails
+     * @throws IllegalArgumentException if path is not a mount point
+     */
+    public void unmount(String fullPath) throws IOException {
+        api.unmount(VMFile.getNormalizedPath(fullPath));
+    }
+
     /**
      * Return a map (fullPath -> FileSystem) of mount points
      * @return a copy of the internal map, sorted by fullPath