| /* |
| * Copyright (C) 2006 The Android Open Source Project |
| * |
| * 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 android.os; |
| import java.io.File; |
| import java.io.FileDescriptor; |
| import java.io.FileInputStream; |
| import java.io.FileNotFoundException; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.net.Socket; |
| |
| /** |
| * The FileDescriptor returned by {@link Parcel#readFileDescriptor}, allowing |
| * you to close it when done with it. |
| */ |
| public class ParcelFileDescriptor implements Parcelable { |
| private final FileDescriptor mFileDescriptor; |
| private boolean mClosed; |
| //this field is to create wrapper for ParcelFileDescriptor using another |
| //PartialFileDescriptor but avoid invoking close twice |
| //consider ParcelFileDescriptor A(fileDescriptor fd), ParcelFileDescriptor B(A) |
| //in this particular case fd.close might be invoked twice. |
| private final ParcelFileDescriptor mParcelDescriptor; |
| |
| /** |
| * For use with {@link #open}: if {@link #MODE_CREATE} has been supplied |
| * and this file doesn't already exist, then create the file with |
| * permissions such that any application can read it. |
| */ |
| public static final int MODE_WORLD_READABLE = 0x00000001; |
| |
| /** |
| * For use with {@link #open}: if {@link #MODE_CREATE} has been supplied |
| * and this file doesn't already exist, then create the file with |
| * permissions such that any application can write it. |
| */ |
| public static final int MODE_WORLD_WRITEABLE = 0x00000002; |
| |
| /** |
| * For use with {@link #open}: open the file with read-only access. |
| */ |
| public static final int MODE_READ_ONLY = 0x10000000; |
| |
| /** |
| * For use with {@link #open}: open the file with write-only access. |
| */ |
| public static final int MODE_WRITE_ONLY = 0x20000000; |
| |
| /** |
| * For use with {@link #open}: open the file with read and write access. |
| */ |
| public static final int MODE_READ_WRITE = 0x30000000; |
| |
| /** |
| * For use with {@link #open}: create the file if it doesn't already exist. |
| */ |
| public static final int MODE_CREATE = 0x08000000; |
| |
| /** |
| * For use with {@link #open}: erase contents of file when opening. |
| */ |
| public static final int MODE_TRUNCATE = 0x04000000; |
| |
| /** |
| * For use with {@link #open}: append to end of file while writing. |
| */ |
| public static final int MODE_APPEND = 0x02000000; |
| |
| /** |
| * Create a new ParcelFileDescriptor accessing a given file. |
| * |
| * @param file The file to be opened. |
| * @param mode The desired access mode, must be one of |
| * {@link #MODE_READ_ONLY}, {@link #MODE_WRITE_ONLY}, or |
| * {@link #MODE_READ_WRITE}; may also be any combination of |
| * {@link #MODE_CREATE}, {@link #MODE_TRUNCATE}, |
| * {@link #MODE_WORLD_READABLE}, and {@link #MODE_WORLD_WRITEABLE}. |
| * |
| * @return Returns a new ParcelFileDescriptor pointing to the given |
| * file. |
| * |
| * @throws FileNotFoundException Throws FileNotFoundException if the given |
| * file does not exist or can not be opened with the requested mode. |
| */ |
| public static ParcelFileDescriptor open(File file, int mode) |
| throws FileNotFoundException { |
| String path = file.getPath(); |
| SecurityManager security = System.getSecurityManager(); |
| if (security != null) { |
| security.checkRead(path); |
| if ((mode&MODE_WRITE_ONLY) != 0) { |
| security.checkWrite(path); |
| } |
| } |
| |
| if ((mode&MODE_READ_WRITE) == 0) { |
| throw new IllegalArgumentException( |
| "Must specify MODE_READ_ONLY, MODE_WRITE_ONLY, or MODE_READ_WRITE"); |
| } |
| |
| FileDescriptor fd = Parcel.openFileDescriptor(path, mode); |
| return fd != null ? new ParcelFileDescriptor(fd) : null; |
| } |
| |
| /** |
| * Create a new ParcelFileDescriptor from the specified Socket. |
| * |
| * @param socket The Socket whose FileDescriptor is used to create |
| * a new ParcelFileDescriptor. |
| * |
| * @return A new ParcelFileDescriptor with the FileDescriptor of the |
| * specified Socket. |
| */ |
| public static ParcelFileDescriptor fromSocket(Socket socket) { |
| FileDescriptor fd = getFileDescriptorFromSocket(socket); |
| return fd != null ? new ParcelFileDescriptor(fd) : null; |
| } |
| |
| // Extracts the file descriptor from the specified socket and returns it untouched |
| private static native FileDescriptor getFileDescriptorFromSocket(Socket socket); |
| |
| /** |
| * Create two ParcelFileDescriptors structured as a data pipe. The first |
| * ParcelFileDescriptor in the returned array is the read side; the second |
| * is the write side. |
| */ |
| public static ParcelFileDescriptor[] createPipe() throws IOException { |
| FileDescriptor[] fds = new FileDescriptor[2]; |
| int res = createPipeNative(fds); |
| if (res == 0) { |
| ParcelFileDescriptor[] pfds = new ParcelFileDescriptor[2]; |
| pfds[0] = new ParcelFileDescriptor(fds[0]); |
| pfds[1] = new ParcelFileDescriptor(fds[1]); |
| return pfds; |
| } |
| throw new IOException("Unable to create pipe: errno=" + -res); |
| } |
| |
| private static native int createPipeNative(FileDescriptor[] outFds); |
| |
| /** |
| * @hide Please use createPipe() or ContentProvider.openPipeHelper(). |
| * Gets a file descriptor for a read-only copy of the given data. |
| * |
| * @param data Data to copy. |
| * @param name Name for the shared memory area that may back the file descriptor. |
| * This is purely informative and may be {@code null}. |
| * @return A ParcelFileDescriptor. |
| * @throws IOException if there is an error while creating the shared memory area. |
| */ |
| @Deprecated |
| public static ParcelFileDescriptor fromData(byte[] data, String name) throws IOException { |
| if (data == null) return null; |
| MemoryFile file = new MemoryFile(name, data.length); |
| if (data.length > 0) { |
| file.writeBytes(data, 0, 0, data.length); |
| } |
| file.deactivate(); |
| FileDescriptor fd = file.getFileDescriptor(); |
| return fd != null ? new ParcelFileDescriptor(fd) : null; |
| } |
| |
| /** |
| * Retrieve the actual FileDescriptor associated with this object. |
| * |
| * @return Returns the FileDescriptor associated with this object. |
| */ |
| public FileDescriptor getFileDescriptor() { |
| return mFileDescriptor; |
| } |
| |
| /** |
| * Return the total size of the file representing this fd, as determined |
| * by stat(). Returns -1 if the fd is not a file. |
| */ |
| public native long getStatSize(); |
| |
| /** |
| * This is needed for implementing AssetFileDescriptor.AutoCloseOutputStream, |
| * and I really don't think we want it to be public. |
| * @hide |
| */ |
| public native long seekTo(long pos); |
| |
| /** |
| * Close the ParcelFileDescriptor. This implementation closes the underlying |
| * OS resources allocated to represent this stream. |
| * |
| * @throws IOException |
| * If an error occurs attempting to close this ParcelFileDescriptor. |
| */ |
| public void close() throws IOException { |
| synchronized (this) { |
| if (mClosed) return; |
| mClosed = true; |
| } |
| if (mParcelDescriptor != null) { |
| // If this is a proxy to another file descriptor, just call through to its |
| // close method. |
| mParcelDescriptor.close(); |
| } else { |
| Parcel.closeFileDescriptor(mFileDescriptor); |
| } |
| } |
| |
| /** |
| * An InputStream you can create on a ParcelFileDescriptor, which will |
| * take care of calling {@link ParcelFileDescriptor#close |
| * ParcelFileDescriptor.close()} for you when the stream is closed. |
| */ |
| public static class AutoCloseInputStream extends FileInputStream { |
| private final ParcelFileDescriptor mFd; |
| |
| public AutoCloseInputStream(ParcelFileDescriptor fd) { |
| super(fd.getFileDescriptor()); |
| mFd = fd; |
| } |
| |
| @Override |
| public void close() throws IOException { |
| try { |
| mFd.close(); |
| } finally { |
| super.close(); |
| } |
| } |
| } |
| |
| /** |
| * An OutputStream you can create on a ParcelFileDescriptor, which will |
| * take care of calling {@link ParcelFileDescriptor#close |
| * ParcelFileDescriptor.close()} for you when the stream is closed. |
| */ |
| public static class AutoCloseOutputStream extends FileOutputStream { |
| private final ParcelFileDescriptor mFd; |
| |
| public AutoCloseOutputStream(ParcelFileDescriptor fd) { |
| super(fd.getFileDescriptor()); |
| mFd = fd; |
| } |
| |
| @Override |
| public void close() throws IOException { |
| try { |
| mFd.close(); |
| } finally { |
| super.close(); |
| } |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "{ParcelFileDescriptor: " + mFileDescriptor + "}"; |
| } |
| |
| @Override |
| protected void finalize() throws Throwable { |
| try { |
| if (!mClosed) { |
| close(); |
| } |
| } finally { |
| super.finalize(); |
| } |
| } |
| |
| public ParcelFileDescriptor(ParcelFileDescriptor descriptor) { |
| super(); |
| mParcelDescriptor = descriptor; |
| mFileDescriptor = mParcelDescriptor.mFileDescriptor; |
| } |
| |
| /*package */ParcelFileDescriptor(FileDescriptor descriptor) { |
| super(); |
| if (descriptor == null) { |
| throw new NullPointerException("descriptor must not be null"); |
| } |
| mFileDescriptor = descriptor; |
| mParcelDescriptor = null; |
| } |
| |
| /* Parcelable interface */ |
| public int describeContents() { |
| return Parcelable.CONTENTS_FILE_DESCRIPTOR; |
| } |
| |
| /** |
| * {@inheritDoc} |
| * If {@link Parcelable#PARCELABLE_WRITE_RETURN_VALUE} is set in flags, |
| * the file descriptor will be closed after a copy is written to the Parcel. |
| */ |
| public void writeToParcel(Parcel out, int flags) { |
| out.writeFileDescriptor(mFileDescriptor); |
| if ((flags&PARCELABLE_WRITE_RETURN_VALUE) != 0 && !mClosed) { |
| try { |
| close(); |
| } catch (IOException e) { |
| // Empty |
| } |
| } |
| } |
| |
| public static final Parcelable.Creator<ParcelFileDescriptor> CREATOR |
| = new Parcelable.Creator<ParcelFileDescriptor>() { |
| public ParcelFileDescriptor createFromParcel(Parcel in) { |
| return in.readFileDescriptor(); |
| } |
| public ParcelFileDescriptor[] newArray(int size) { |
| return new ParcelFileDescriptor[size]; |
| } |
| }; |
| |
| } |