The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package android.os; |
| 18 | import java.io.File; |
| 19 | import java.io.FileDescriptor; |
| 20 | import java.io.FileInputStream; |
| 21 | import java.io.FileNotFoundException; |
| 22 | import java.io.FileOutputStream; |
| 23 | import java.io.IOException; |
| 24 | import java.net.Socket; |
| 25 | |
| 26 | /** |
| 27 | * The FileDescriptor returned by {@link Parcel#readFileDescriptor}, allowing |
| 28 | * you to close it when done with it. |
| 29 | */ |
| 30 | public class ParcelFileDescriptor implements Parcelable { |
| 31 | private final FileDescriptor mFileDescriptor; |
| 32 | private boolean mClosed; |
| 33 | //this field is to create wrapper for ParcelFileDescriptor using another |
| 34 | //PartialFileDescriptor but avoid invoking close twice |
| 35 | //consider ParcelFileDescriptor A(fileDescriptor fd), ParcelFileDescriptor B(A) |
| 36 | //in this particular case fd.close might be invoked twice. |
| 37 | private final ParcelFileDescriptor mParcelDescriptor; |
| 38 | |
| 39 | /** |
| 40 | * For use with {@link #open}: if {@link #MODE_CREATE} has been supplied |
| 41 | * and this file doesn't already exist, then create the file with |
| 42 | * permissions such that any application can read it. |
| 43 | */ |
| 44 | public static final int MODE_WORLD_READABLE = 0x00000001; |
| 45 | |
| 46 | /** |
| 47 | * For use with {@link #open}: if {@link #MODE_CREATE} has been supplied |
| 48 | * and this file doesn't already exist, then create the file with |
| 49 | * permissions such that any application can write it. |
| 50 | */ |
| 51 | public static final int MODE_WORLD_WRITEABLE = 0x00000002; |
| 52 | |
| 53 | /** |
| 54 | * For use with {@link #open}: open the file with read-only access. |
| 55 | */ |
| 56 | public static final int MODE_READ_ONLY = 0x10000000; |
| 57 | |
| 58 | /** |
| 59 | * For use with {@link #open}: open the file with write-only access. |
| 60 | */ |
| 61 | public static final int MODE_WRITE_ONLY = 0x20000000; |
| 62 | |
| 63 | /** |
| 64 | * For use with {@link #open}: open the file with read and write access. |
| 65 | */ |
| 66 | public static final int MODE_READ_WRITE = 0x30000000; |
| 67 | |
| 68 | /** |
| 69 | * For use with {@link #open}: create the file if it doesn't already exist. |
| 70 | */ |
| 71 | public static final int MODE_CREATE = 0x08000000; |
| 72 | |
| 73 | /** |
| 74 | * For use with {@link #open}: erase contents of file when opening. |
| 75 | */ |
| 76 | public static final int MODE_TRUNCATE = 0x04000000; |
| 77 | |
| 78 | /** |
| 79 | * For use with {@link #open}: append to end of file while writing. |
| 80 | */ |
| 81 | public static final int MODE_APPEND = 0x02000000; |
| 82 | |
| 83 | /** |
| 84 | * Create a new ParcelFileDescriptor accessing a given file. |
| 85 | * |
| 86 | * @param file The file to be opened. |
| 87 | * @param mode The desired access mode, must be one of |
| 88 | * {@link #MODE_READ_ONLY}, {@link #MODE_WRITE_ONLY}, or |
| 89 | * {@link #MODE_READ_WRITE}; may also be any combination of |
| 90 | * {@link #MODE_CREATE}, {@link #MODE_TRUNCATE}, |
| 91 | * {@link #MODE_WORLD_READABLE}, and {@link #MODE_WORLD_WRITEABLE}. |
| 92 | * |
| 93 | * @return Returns a new ParcelFileDescriptor pointing to the given |
| 94 | * file. |
| 95 | * |
| 96 | * @throws FileNotFoundException Throws FileNotFoundException if the given |
| 97 | * file does not exist or can not be opened with the requested mode. |
| 98 | */ |
| 99 | public static ParcelFileDescriptor open(File file, int mode) |
| 100 | throws FileNotFoundException { |
| 101 | String path = file.getPath(); |
| 102 | SecurityManager security = System.getSecurityManager(); |
| 103 | if (security != null) { |
| 104 | security.checkRead(path); |
| 105 | if ((mode&MODE_WRITE_ONLY) != 0) { |
| 106 | security.checkWrite(path); |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | if ((mode&MODE_READ_WRITE) == 0) { |
| 111 | throw new IllegalArgumentException( |
| 112 | "Must specify MODE_READ_ONLY, MODE_WRITE_ONLY, or MODE_READ_WRITE"); |
| 113 | } |
| 114 | |
| 115 | FileDescriptor fd = Parcel.openFileDescriptor(path, mode); |
Dianne Hackborn | 1866839 | 2010-03-23 22:10:55 -0700 | [diff] [blame] | 116 | return fd != null ? new ParcelFileDescriptor(fd) : null; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Create a new ParcelFileDescriptor from the specified Socket. |
| 121 | * |
| 122 | * @param socket The Socket whose FileDescriptor is used to create |
| 123 | * a new ParcelFileDescriptor. |
| 124 | * |
| 125 | * @return A new ParcelFileDescriptor with the FileDescriptor of the |
| 126 | * specified Socket. |
| 127 | */ |
| 128 | public static ParcelFileDescriptor fromSocket(Socket socket) { |
| 129 | FileDescriptor fd = getFileDescriptorFromSocket(socket); |
Dianne Hackborn | 1866839 | 2010-03-23 22:10:55 -0700 | [diff] [blame] | 130 | return fd != null ? new ParcelFileDescriptor(fd) : null; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 131 | } |
| 132 | |
| 133 | // Extracts the file descriptor from the specified socket and returns it untouched |
| 134 | private static native FileDescriptor getFileDescriptorFromSocket(Socket socket); |
| 135 | |
| 136 | /** |
Dianne Hackborn | 23fdaf6 | 2010-08-06 12:16:55 -0700 | [diff] [blame] | 137 | * Create two ParcelFileDescriptors structured as a data pipe. The first |
| 138 | * ParcelFileDescriptor in the returned array is the read side; the second |
| 139 | * is the write side. |
| 140 | */ |
| 141 | public static ParcelFileDescriptor[] createPipe() throws IOException { |
| 142 | FileDescriptor[] fds = new FileDescriptor[2]; |
| 143 | int res = createPipeNative(fds); |
| 144 | if (res == 0) { |
| 145 | ParcelFileDescriptor[] pfds = new ParcelFileDescriptor[2]; |
| 146 | pfds[0] = new ParcelFileDescriptor(fds[0]); |
| 147 | pfds[1] = new ParcelFileDescriptor(fds[1]); |
| 148 | return pfds; |
| 149 | } |
| 150 | throw new IOException("Unable to create pipe: errno=" + -res); |
| 151 | } |
| 152 | |
| 153 | private static native int createPipeNative(FileDescriptor[] outFds); |
| 154 | |
| 155 | /** |
Dianne Hackborn | 540f86a | 2011-01-11 17:52:22 -0800 | [diff] [blame] | 156 | * @hide Please use createPipe() or ContentProvider.openPipeHelper(). |
Bjorn Bringert | a006b472 | 2010-04-14 14:43:26 +0100 | [diff] [blame] | 157 | * Gets a file descriptor for a read-only copy of the given data. |
| 158 | * |
| 159 | * @param data Data to copy. |
| 160 | * @param name Name for the shared memory area that may back the file descriptor. |
| 161 | * This is purely informative and may be {@code null}. |
| 162 | * @return A ParcelFileDescriptor. |
| 163 | * @throws IOException if there is an error while creating the shared memory area. |
| 164 | */ |
Dianne Hackborn | a2ea747 | 2010-12-20 12:10:01 -0800 | [diff] [blame] | 165 | @Deprecated |
Bjorn Bringert | a006b472 | 2010-04-14 14:43:26 +0100 | [diff] [blame] | 166 | public static ParcelFileDescriptor fromData(byte[] data, String name) throws IOException { |
| 167 | if (data == null) return null; |
| 168 | MemoryFile file = new MemoryFile(name, data.length); |
| 169 | if (data.length > 0) { |
| 170 | file.writeBytes(data, 0, 0, data.length); |
| 171 | } |
| 172 | file.deactivate(); |
| 173 | FileDescriptor fd = file.getFileDescriptor(); |
| 174 | return fd != null ? new ParcelFileDescriptor(fd) : null; |
| 175 | } |
| 176 | |
| 177 | /** |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 178 | * Retrieve the actual FileDescriptor associated with this object. |
| 179 | * |
| 180 | * @return Returns the FileDescriptor associated with this object. |
| 181 | */ |
| 182 | public FileDescriptor getFileDescriptor() { |
| 183 | return mFileDescriptor; |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Return the total size of the file representing this fd, as determined |
| 188 | * by stat(). Returns -1 if the fd is not a file. |
| 189 | */ |
| 190 | public native long getStatSize(); |
| 191 | |
| 192 | /** |
| 193 | * This is needed for implementing AssetFileDescriptor.AutoCloseOutputStream, |
| 194 | * and I really don't think we want it to be public. |
| 195 | * @hide |
| 196 | */ |
| 197 | public native long seekTo(long pos); |
| 198 | |
| 199 | /** |
| 200 | * Close the ParcelFileDescriptor. This implementation closes the underlying |
| 201 | * OS resources allocated to represent this stream. |
| 202 | * |
| 203 | * @throws IOException |
| 204 | * If an error occurs attempting to close this ParcelFileDescriptor. |
| 205 | */ |
| 206 | public void close() throws IOException { |
Dianne Hackborn | 1866839 | 2010-03-23 22:10:55 -0700 | [diff] [blame] | 207 | synchronized (this) { |
| 208 | if (mClosed) return; |
| 209 | mClosed = true; |
| 210 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 211 | if (mParcelDescriptor != null) { |
| 212 | // If this is a proxy to another file descriptor, just call through to its |
| 213 | // close method. |
| 214 | mParcelDescriptor.close(); |
| 215 | } else { |
| 216 | Parcel.closeFileDescriptor(mFileDescriptor); |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * An InputStream you can create on a ParcelFileDescriptor, which will |
| 222 | * take care of calling {@link ParcelFileDescriptor#close |
Christopher Tate | fa9e7c0 | 2010-05-06 12:07:10 -0700 | [diff] [blame] | 223 | * ParcelFileDescriptor.close()} for you when the stream is closed. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 224 | */ |
| 225 | public static class AutoCloseInputStream extends FileInputStream { |
| 226 | private final ParcelFileDescriptor mFd; |
| 227 | |
| 228 | public AutoCloseInputStream(ParcelFileDescriptor fd) { |
| 229 | super(fd.getFileDescriptor()); |
| 230 | mFd = fd; |
| 231 | } |
| 232 | |
| 233 | @Override |
| 234 | public void close() throws IOException { |
Brian Carlstrom | fd9ddd1 | 2010-11-04 11:24:58 -0700 | [diff] [blame] | 235 | try { |
| 236 | mFd.close(); |
| 237 | } finally { |
| 238 | super.close(); |
| 239 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 240 | } |
| 241 | } |
| 242 | |
| 243 | /** |
| 244 | * An OutputStream you can create on a ParcelFileDescriptor, which will |
| 245 | * take care of calling {@link ParcelFileDescriptor#close |
Christopher Tate | fa9e7c0 | 2010-05-06 12:07:10 -0700 | [diff] [blame] | 246 | * ParcelFileDescriptor.close()} for you when the stream is closed. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 247 | */ |
| 248 | public static class AutoCloseOutputStream extends FileOutputStream { |
| 249 | private final ParcelFileDescriptor mFd; |
| 250 | |
| 251 | public AutoCloseOutputStream(ParcelFileDescriptor fd) { |
| 252 | super(fd.getFileDescriptor()); |
| 253 | mFd = fd; |
| 254 | } |
| 255 | |
| 256 | @Override |
| 257 | public void close() throws IOException { |
Brian Carlstrom | fd9ddd1 | 2010-11-04 11:24:58 -0700 | [diff] [blame] | 258 | try { |
| 259 | mFd.close(); |
| 260 | } finally { |
| 261 | super.close(); |
| 262 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 263 | } |
| 264 | } |
| 265 | |
| 266 | @Override |
| 267 | public String toString() { |
| 268 | return "{ParcelFileDescriptor: " + mFileDescriptor + "}"; |
| 269 | } |
| 270 | |
| 271 | @Override |
| 272 | protected void finalize() throws Throwable { |
| 273 | try { |
| 274 | if (!mClosed) { |
| 275 | close(); |
| 276 | } |
| 277 | } finally { |
| 278 | super.finalize(); |
| 279 | } |
| 280 | } |
| 281 | |
| 282 | public ParcelFileDescriptor(ParcelFileDescriptor descriptor) { |
| 283 | super(); |
| 284 | mParcelDescriptor = descriptor; |
| 285 | mFileDescriptor = mParcelDescriptor.mFileDescriptor; |
| 286 | } |
| 287 | |
| 288 | /*package */ParcelFileDescriptor(FileDescriptor descriptor) { |
| 289 | super(); |
Dianne Hackborn | 1866839 | 2010-03-23 22:10:55 -0700 | [diff] [blame] | 290 | if (descriptor == null) { |
| 291 | throw new NullPointerException("descriptor must not be null"); |
| 292 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 293 | mFileDescriptor = descriptor; |
| 294 | mParcelDescriptor = null; |
| 295 | } |
| 296 | |
| 297 | /* Parcelable interface */ |
| 298 | public int describeContents() { |
| 299 | return Parcelable.CONTENTS_FILE_DESCRIPTOR; |
| 300 | } |
| 301 | |
Dan Egnor | b3e4ef3 | 2010-07-20 09:03:35 -0700 | [diff] [blame] | 302 | /** |
| 303 | * {@inheritDoc} |
| 304 | * If {@link Parcelable#PARCELABLE_WRITE_RETURN_VALUE} is set in flags, |
| 305 | * the file descriptor will be closed after a copy is written to the Parcel. |
| 306 | */ |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 307 | public void writeToParcel(Parcel out, int flags) { |
| 308 | out.writeFileDescriptor(mFileDescriptor); |
| 309 | if ((flags&PARCELABLE_WRITE_RETURN_VALUE) != 0 && !mClosed) { |
| 310 | try { |
| 311 | close(); |
| 312 | } catch (IOException e) { |
| 313 | // Empty |
| 314 | } |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | public static final Parcelable.Creator<ParcelFileDescriptor> CREATOR |
| 319 | = new Parcelable.Creator<ParcelFileDescriptor>() { |
| 320 | public ParcelFileDescriptor createFromParcel(Parcel in) { |
| 321 | return in.readFileDescriptor(); |
| 322 | } |
| 323 | public ParcelFileDescriptor[] newArray(int size) { |
| 324 | return new ParcelFileDescriptor[size]; |
| 325 | } |
| 326 | }; |
| 327 | |
| 328 | } |