Add removable drive manager with placeholder task implementations.

bramble-android/src/main/java/org/briarproject/bramble/plugin/file/AndroidRemovableDrivePlugin.java

@@ -12,7 +12,7 @@ import java.io.OutputStream;
 
 import javax.annotation.concurrent.Immutable;
 
-import static org.briarproject.bramble.api.plugin.RemovableDriveConstants.PROP_URI;
+import static org.briarproject.bramble.api.plugin.file.RemovableDriveConstants.PROP_URI;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
 
 @Immutable

bramble-android/src/main/java/org/briarproject/bramble/plugin/file/AndroidRemovableDrivePluginFactory.java

@@ -13,7 +13,7 @@ import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
 import static java.util.concurrent.TimeUnit.DAYS;
-import static org.briarproject.bramble.api.plugin.RemovableDriveConstants.ID;
+import static org.briarproject.bramble.api.plugin.file.RemovableDriveConstants.ID;
 
 @Immutable
 @NotNullByDefault

bramble-api/src/main/java/org/briarproject/bramble/api/Consumer.java

@@ -0,0 +1,9 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface Consumer<T> {
+
+	void accept(T t);
+}

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/file/FileConstants.java

@@ -1,4 +1,4 @@
-package org.briarproject.bramble.api.plugin;
+package org.briarproject.bramble.api.plugin.file;
 
 public interface FileConstants {
 

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/file/RemovableDriveConstants.java

@@ -1,4 +1,6 @@
-package org.briarproject.bramble.api.plugin;
+package org.briarproject.bramble.api.plugin.file;
+
+import org.briarproject.bramble.api.plugin.TransportId;
 
 public interface RemovableDriveConstants {
 

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/file/RemovableDriveManager.java

@@ -0,0 +1,40 @@
+package org.briarproject.bramble.api.plugin.file;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.io.File;
+
+import javax.annotation.Nullable;
+
+@NotNullByDefault
+public interface RemovableDriveManager {
+
+	/**
+	 * Returns the currently running reader task for the given contact,
+	 * or null if no task is running.
+	 */
+	@Nullable
+	RemovableDriveTask getCurrentReaderTask(ContactId c);
+
+	/**
+	 * Returns the currently running writer task for the given contact,
+	 * or null if no task is running.
+	 */
+	@Nullable
+	RemovableDriveTask getCurrentWriterTask(ContactId c);
+
+	/**
+	 * Starts and returns a reader task for the given contact, reading from
+	 * the given file. If a reader task for the contact is already running,
+	 * it will be returned and the file argument will be ignored.
+	 */
+	RemovableDriveTask startReaderTask(ContactId c, File f);
+
+	/**
+	 * Starts and returns a writer task for the given contact, writing to
+	 * the given file. If a writer task for the contact is already running,
+	 * it will be returned and the file argument will be ignored.
+	 */
+	RemovableDriveTask startWriterTask(ContactId c, File f);
+}

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/file/RemovableDriveTask.java

@@ -0,0 +1,34 @@
+package org.briarproject.bramble.api.plugin.file;
+
+import org.briarproject.bramble.api.event.EventExecutor;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.io.File;
+
+@NotNullByDefault
+public interface RemovableDriveTask {
+
+	/**
+	 * Returns the file that this task is reading from or writing to.
+	 */
+	File getFile();
+
+	/**
+	 * Adds an observer to the task.
+	 */
+	void addObserver(Observer o);
+
+	/**
+	 * Removes an observer from the task.
+	 */
+	void removeObserver(Observer o);
+
+	interface Observer {
+
+		@EventExecutor
+		void onProgress(long written, long total);
+
+		@EventExecutor
+		void onCompletion(boolean success);
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/AbstractRemovableDrivePlugin.java

@@ -20,7 +20,7 @@ import javax.annotation.concurrent.Immutable;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.plugin.Plugin.State.ACTIVE;
-import static org.briarproject.bramble.api.plugin.RemovableDriveConstants.ID;
+import static org.briarproject.bramble.api.plugin.file.RemovableDriveConstants.ID;
 import static org.briarproject.bramble.util.LogUtils.logException;
 
 @Immutable

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FilePlugin.java

@@ -15,8 +15,8 @@ import java.util.logging.Logger;
 
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
-import static org.briarproject.bramble.api.plugin.FileConstants.PROP_PATH;
 import static org.briarproject.bramble.api.plugin.Plugin.State.ACTIVE;
+import static org.briarproject.bramble.api.plugin.file.FileConstants.PROP_PATH;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
 

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriveManagerImpl.java

@@ -0,0 +1,83 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.event.EventExecutor;
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.file.RemovableDriveManager;
+import org.briarproject.bramble.api.plugin.file.RemovableDriveTask;
+
+import java.io.File;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executor;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.ThreadSafe;
+import javax.inject.Inject;
+
+@ThreadSafe
+@NotNullByDefault
+class RemovableDriveManagerImpl
+		implements RemovableDriveManager, RemovableDriveTaskRegistry {
+
+	private final Executor ioExecutor, eventExecutor;
+	private final ConcurrentHashMap<ContactId, RemovableDriveTask>
+			readers = new ConcurrentHashMap<>();
+	private final ConcurrentHashMap<ContactId, RemovableDriveTask>
+			writers = new ConcurrentHashMap<>();
+
+	@Inject
+	RemovableDriveManagerImpl(@IoExecutor Executor ioExecutor,
+			@EventExecutor Executor eventExecutor) {
+		this.ioExecutor = ioExecutor;
+		this.eventExecutor = eventExecutor;
+	}
+
+	@Nullable
+	@Override
+	public RemovableDriveTask getCurrentReaderTask(ContactId c) {
+		return readers.get(c);
+	}
+
+	@Nullable
+	@Override
+	public RemovableDriveTask getCurrentWriterTask(ContactId c) {
+		return writers.get(c);
+	}
+
+	@Override
+	public RemovableDriveTask startReaderTask(ContactId c, File f) {
+		RemovableDriverReaderTask task =
+				new RemovableDriverReaderTask(eventExecutor, this, c, f);
+		RemovableDriveTask old = readers.putIfAbsent(c, task);
+		if (old == null) {
+			ioExecutor.execute(task);
+			return task;
+		} else {
+			return old;
+		}
+	}
+
+	@Override
+	public RemovableDriveTask startWriterTask(ContactId c, File f) {
+		RemovableDriverWriterTask task =
+				new RemovableDriverWriterTask(eventExecutor, this, c, f);
+		RemovableDriveTask old = writers.putIfAbsent(c, task);
+		if (old == null) {
+			ioExecutor.execute(task);
+			return task;
+		} else {
+			return old;
+		}
+	}
+
+	@Override
+	public void removeReader(ContactId c, RemovableDriveTask task) {
+		readers.remove(c, task);
+	}
+
+	@Override
+	public void removeWriter(ContactId c, RemovableDriveTask task) {
+		writers.remove(c, task);
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriveModule.java

@@ -0,0 +1,19 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.plugin.file.RemovableDriveManager;
+
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class RemovableDriveModule {
+
+	@Provides
+	@Singleton
+	RemovableDriveManager provideRemovableDriveManager(
+			RemovableDriveManagerImpl removableDriveManager) {
+		return removableDriveManager;
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDrivePlugin.java

@@ -11,7 +11,7 @@ import java.io.OutputStream;
 
 import javax.annotation.concurrent.Immutable;
 
-import static org.briarproject.bramble.api.plugin.RemovableDriveConstants.PROP_PATH;
+import static org.briarproject.bramble.api.plugin.file.RemovableDriveConstants.PROP_PATH;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
 
 @Immutable

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDrivePluginFactory.java

@@ -11,7 +11,7 @@ import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
 import static java.util.concurrent.TimeUnit.DAYS;
-import static org.briarproject.bramble.api.plugin.RemovableDriveConstants.ID;
+import static org.briarproject.bramble.api.plugin.file.RemovableDriveConstants.ID;
 
 @Immutable
 @NotNullByDefault

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriveTaskImpl.java

@@ -0,0 +1,54 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.Consumer;
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.file.RemovableDriveTask;
+
+import java.io.File;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executor;
+
+import javax.annotation.concurrent.ThreadSafe;
+
+@ThreadSafe
+@NotNullByDefault
+abstract class RemovableDriveTaskImpl implements RemovableDriveTask, Runnable {
+
+	private final Executor eventExecutor;
+	final RemovableDriveTaskRegistry registry;
+	final ContactId contactId;
+	final File file;
+	private final List<Observer> observers = new CopyOnWriteArrayList<>();
+
+	RemovableDriveTaskImpl(Executor eventExecutor,
+			RemovableDriveTaskRegistry registry, ContactId contactId,
+			File file) {
+		this.contactId = contactId;
+		this.file = file;
+		this.registry = registry;
+		this.eventExecutor = eventExecutor;
+	}
+
+	@Override
+	public File getFile() {
+		return file;
+	}
+
+	@Override
+	public void addObserver(Observer o) {
+		observers.add(o);
+	}
+
+	@Override
+	public void removeObserver(Observer o) {
+		observers.remove(o);
+	}
+
+	void visitObservers(Consumer<Observer> visitor) {
+		eventExecutor.execute(() -> {
+			for (Observer o : observers) visitor.accept(o);
+		});
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriveTaskRegistry.java

@@ -0,0 +1,13 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.plugin.file.RemovableDriveTask;
+
+@NotNullByDefault
+interface RemovableDriveTaskRegistry {
+
+	void removeReader(ContactId c, RemovableDriveTask task);
+
+	void removeWriter(ContactId c, RemovableDriveTask task);
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriverReaderTask.java

@@ -0,0 +1,46 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.IoUtils.tryToClose;
+import static org.briarproject.bramble.util.LogUtils.logException;
+
+@NotNullByDefault
+class RemovableDriverReaderTask extends RemovableDriveTaskImpl {
+
+	private final static Logger LOG =
+			getLogger(RemovableDriverReaderTask.class.getName());
+
+	RemovableDriverReaderTask(Executor eventExecutor,
+			RemovableDriveTaskRegistry registry, ContactId contactId,
+			File file) {
+		super(eventExecutor, registry, contactId, file);
+	}
+
+	@Override
+	public void run() {
+		// TODO
+		InputStream in = null;
+		try {
+			visitObservers(o -> o.onProgress(0, 100));
+			in = new FileInputStream(file);
+			visitObservers(o -> o.onCompletion(true));
+		} catch (IOException e) {
+			logException(LOG, WARNING, e);
+			visitObservers(o -> o.onCompletion(false));
+		} finally {
+			tryToClose(in, LOG, WARNING);
+			registry.removeReader(contactId, this);
+		}
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/plugin/file/RemovableDriverWriterTask.java

@@ -0,0 +1,46 @@
+package org.briarproject.bramble.plugin.file;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.concurrent.Executor;
+import java.util.logging.Logger;
+
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.util.IoUtils.tryToClose;
+import static org.briarproject.bramble.util.LogUtils.logException;
+
+@NotNullByDefault
+class RemovableDriverWriterTask extends RemovableDriveTaskImpl {
+
+	private static final Logger LOG =
+			getLogger(RemovableDriverWriterTask.class.getName());
+
+	RemovableDriverWriterTask(Executor eventExecutor,
+			RemovableDriveTaskRegistry registry, ContactId contactId,
+			File file) {
+		super(eventExecutor, registry, contactId, file);
+	}
+
+	@Override
+	public void run() {
+		// TODO
+		OutputStream out = null;
+		try {
+			visitObservers(o -> o.onProgress(0, 100));
+			out = new FileOutputStream(file);
+			visitObservers(o -> o.onCompletion(true));
+		} catch (IOException e) {
+			logException(LOG, WARNING, e);
+			visitObservers(o -> o.onCompletion(false));
+		} finally {
+			tryToClose(out, LOG, WARNING);
+			registry.removeWriter(contactId, this);
+		}
+	}
+}

briar-android/src/main/java/org/briarproject/briar/android/AndroidComponent.java

@@ -28,6 +28,7 @@ import org.briarproject.bramble.api.system.AndroidExecutor;
 import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.LocationUtils;
+import org.briarproject.bramble.plugin.file.RemovableDriveModule;
 import org.briarproject.bramble.plugin.tor.CircumventionProvider;
 import org.briarproject.bramble.system.ClockModule;
 import org.briarproject.briar.BriarCoreEagerSingletons;
@@ -83,7 +84,8 @@ import dagger.Component;
 		AppModule.class,
 		AttachmentModule.class,
 		ClockModule.class,
-		MediaModule.class
+		MediaModule.class,
+		RemovableDriveModule.class
 })
 public interface AndroidComponent
 		extends BrambleCoreEagerSingletons, BrambleAndroidEagerSingletons,