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 | |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 19 | import android.util.Log; |
Jeff Sharkey | 184a010 | 2013-07-10 16:19:52 -0700 | [diff] [blame] | 20 | import android.util.Slog; |
| 21 | |
| 22 | import libcore.io.ErrnoException; |
| 23 | import libcore.io.IoUtils; |
| 24 | import libcore.io.Libcore; |
| 25 | import libcore.io.OsConstants; |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 26 | |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 27 | import java.io.BufferedInputStream; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 28 | import java.io.ByteArrayOutputStream; |
| 29 | import java.io.File; |
Jeff Sharkey | 184a010 | 2013-07-10 16:19:52 -0700 | [diff] [blame] | 30 | import java.io.FileDescriptor; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 31 | import java.io.FileInputStream; |
Wink Saville | 6d25a99 | 2011-06-03 17:03:51 -0700 | [diff] [blame] | 32 | import java.io.FileNotFoundException; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 33 | import java.io.FileOutputStream; |
Mike Lockwood | da8bb74 | 2011-05-28 13:24:04 -0400 | [diff] [blame] | 34 | import java.io.FileWriter; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 35 | import java.io.IOException; |
| 36 | import java.io.InputStream; |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 37 | import java.util.Arrays; |
| 38 | import java.util.Comparator; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 39 | import java.util.regex.Pattern; |
Wink Saville | 6d25a99 | 2011-06-03 17:03:51 -0700 | [diff] [blame] | 40 | import java.util.zip.CRC32; |
| 41 | import java.util.zip.CheckedInputStream; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 42 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 43 | /** |
| 44 | * Tools for managing files. Not for public consumption. |
| 45 | * @hide |
| 46 | */ |
Wink Saville | 6d25a99 | 2011-06-03 17:03:51 -0700 | [diff] [blame] | 47 | public class FileUtils { |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 48 | private static final String TAG = "FileUtils"; |
| 49 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 50 | public static final int S_IRWXU = 00700; |
| 51 | public static final int S_IRUSR = 00400; |
| 52 | public static final int S_IWUSR = 00200; |
| 53 | public static final int S_IXUSR = 00100; |
| 54 | |
| 55 | public static final int S_IRWXG = 00070; |
| 56 | public static final int S_IRGRP = 00040; |
| 57 | public static final int S_IWGRP = 00020; |
| 58 | public static final int S_IXGRP = 00010; |
| 59 | |
| 60 | public static final int S_IRWXO = 00007; |
| 61 | public static final int S_IROTH = 00004; |
| 62 | public static final int S_IWOTH = 00002; |
| 63 | public static final int S_IXOTH = 00001; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 64 | |
| 65 | /** Regular expression for safe filenames: no spaces or metacharacters */ |
| 66 | private static final Pattern SAFE_FILENAME_PATTERN = Pattern.compile("[\\w%+,./=_-]+"); |
| 67 | |
Jeff Sharkey | 184a010 | 2013-07-10 16:19:52 -0700 | [diff] [blame] | 68 | /** |
| 69 | * Set owner and mode of of given {@link File}. |
| 70 | * |
| 71 | * @param mode to apply through {@code chmod} |
| 72 | * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| 73 | * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| 74 | * @return 0 on success, otherwise errno. |
| 75 | */ |
| 76 | public static int setPermissions(File path, int mode, int uid, int gid) { |
| 77 | return setPermissions(path.getAbsolutePath(), mode, uid, gid); |
| 78 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 79 | |
Jeff Sharkey | 184a010 | 2013-07-10 16:19:52 -0700 | [diff] [blame] | 80 | /** |
| 81 | * Set owner and mode of of given path. |
| 82 | * |
| 83 | * @param mode to apply through {@code chmod} |
| 84 | * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| 85 | * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| 86 | * @return 0 on success, otherwise errno. |
| 87 | */ |
| 88 | public static int setPermissions(String path, int mode, int uid, int gid) { |
| 89 | try { |
| 90 | Libcore.os.chmod(path, mode); |
| 91 | } catch (ErrnoException e) { |
| 92 | Slog.w(TAG, "Failed to chmod(" + path + "): " + e); |
| 93 | return e.errno; |
| 94 | } |
| 95 | |
| 96 | if (uid >= 0 || gid >= 0) { |
| 97 | try { |
| 98 | Libcore.os.chown(path, uid, gid); |
| 99 | } catch (ErrnoException e) { |
| 100 | Slog.w(TAG, "Failed to chown(" + path + "): " + e); |
| 101 | return e.errno; |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | return 0; |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Set owner and mode of of given {@link FileDescriptor}. |
| 110 | * |
| 111 | * @param mode to apply through {@code chmod} |
| 112 | * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| 113 | * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| 114 | * @return 0 on success, otherwise errno. |
| 115 | */ |
| 116 | public static int setPermissions(FileDescriptor fd, int mode, int uid, int gid) { |
| 117 | try { |
| 118 | Libcore.os.fchmod(fd, mode); |
| 119 | } catch (ErrnoException e) { |
| 120 | Slog.w(TAG, "Failed to fchmod(): " + e); |
| 121 | return e.errno; |
| 122 | } |
| 123 | |
| 124 | if (uid >= 0 || gid >= 0) { |
| 125 | try { |
| 126 | Libcore.os.fchown(fd, uid, gid); |
| 127 | } catch (ErrnoException e) { |
| 128 | Slog.w(TAG, "Failed to fchown(): " + e); |
| 129 | return e.errno; |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * Return owning UID of given path, otherwise -1. |
| 138 | */ |
| 139 | public static int getUid(String path) { |
| 140 | try { |
| 141 | return Libcore.os.stat(path).st_uid; |
| 142 | } catch (ErrnoException e) { |
| 143 | return -1; |
| 144 | } |
| 145 | } |
Dianne Hackborn | 053f61d | 2013-06-26 18:07:43 -0700 | [diff] [blame] | 146 | |
Dianne Hackborn | 8bdf593 | 2010-10-15 12:54:40 -0700 | [diff] [blame] | 147 | /** |
| 148 | * Perform an fsync on the given FileOutputStream. The stream at this |
| 149 | * point must be flushed but not yet closed. |
| 150 | */ |
| 151 | public static boolean sync(FileOutputStream stream) { |
| 152 | try { |
| 153 | if (stream != null) { |
| 154 | stream.getFD().sync(); |
| 155 | } |
| 156 | return true; |
| 157 | } catch (IOException e) { |
| 158 | } |
| 159 | return false; |
| 160 | } |
| 161 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 162 | // copy a file from srcFile to destFile, return true if succeed, return |
| 163 | // false if fail |
| 164 | public static boolean copyFile(File srcFile, File destFile) { |
| 165 | boolean result = false; |
| 166 | try { |
| 167 | InputStream in = new FileInputStream(srcFile); |
| 168 | try { |
| 169 | result = copyToFile(in, destFile); |
| 170 | } finally { |
| 171 | in.close(); |
| 172 | } |
| 173 | } catch (IOException e) { |
| 174 | result = false; |
| 175 | } |
| 176 | return result; |
| 177 | } |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 178 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 179 | /** |
| 180 | * Copy data from a source stream to destFile. |
| 181 | * Return true if succeed, return false if failed. |
| 182 | */ |
| 183 | public static boolean copyToFile(InputStream inputStream, File destFile) { |
| 184 | try { |
Dianne Hackborn | 1afd1c9 | 2010-03-18 22:47:17 -0700 | [diff] [blame] | 185 | if (destFile.exists()) { |
| 186 | destFile.delete(); |
| 187 | } |
Dianne Hackborn | 8bdf593 | 2010-10-15 12:54:40 -0700 | [diff] [blame] | 188 | FileOutputStream out = new FileOutputStream(destFile); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 189 | try { |
| 190 | byte[] buffer = new byte[4096]; |
| 191 | int bytesRead; |
| 192 | while ((bytesRead = inputStream.read(buffer)) >= 0) { |
| 193 | out.write(buffer, 0, bytesRead); |
| 194 | } |
| 195 | } finally { |
Dianne Hackborn | 8bdf593 | 2010-10-15 12:54:40 -0700 | [diff] [blame] | 196 | out.flush(); |
| 197 | try { |
| 198 | out.getFD().sync(); |
| 199 | } catch (IOException e) { |
| 200 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 201 | out.close(); |
| 202 | } |
| 203 | return true; |
| 204 | } catch (IOException e) { |
| 205 | return false; |
| 206 | } |
| 207 | } |
| 208 | |
| 209 | /** |
| 210 | * Check if a filename is "safe" (no metacharacters or spaces). |
| 211 | * @param file The file to check |
| 212 | */ |
| 213 | public static boolean isFilenameSafe(File file) { |
| 214 | // Note, we check whether it matches what's known to be safe, |
| 215 | // rather than what's known to be unsafe. Non-ASCII, control |
| 216 | // characters, etc. are all unsafe by default. |
| 217 | return SAFE_FILENAME_PATTERN.matcher(file.getPath()).matches(); |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * Read a text file into a String, optionally limiting the length. |
| 222 | * @param file to read (will not seek, so things like /proc files are OK) |
| 223 | * @param max length (positive for head, negative of tail, 0 for no limit) |
| 224 | * @param ellipsis to add of the file was truncated (can be null) |
| 225 | * @return the contents of the file, possibly truncated |
| 226 | * @throws IOException if something goes wrong reading the file |
| 227 | */ |
| 228 | public static String readTextFile(File file, int max, String ellipsis) throws IOException { |
| 229 | InputStream input = new FileInputStream(file); |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 230 | // wrapping a BufferedInputStream around it because when reading /proc with unbuffered |
| 231 | // input stream, bytes read not equal to buffer size is not necessarily the correct |
| 232 | // indication for EOF; but it is true for BufferedInputStream due to its implementation. |
| 233 | BufferedInputStream bis = new BufferedInputStream(input); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 234 | try { |
Dan Egnor | 42471dd | 2010-01-07 17:25:22 -0800 | [diff] [blame] | 235 | long size = file.length(); |
| 236 | if (max > 0 || (size > 0 && max == 0)) { // "head" mode: read the first N bytes |
| 237 | if (size > 0 && (max == 0 || size < max)) max = (int) size; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 238 | byte[] data = new byte[max + 1]; |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 239 | int length = bis.read(data); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 240 | if (length <= 0) return ""; |
| 241 | if (length <= max) return new String(data, 0, length); |
| 242 | if (ellipsis == null) return new String(data, 0, max); |
| 243 | return new String(data, 0, max) + ellipsis; |
Dan Egnor | 42471dd | 2010-01-07 17:25:22 -0800 | [diff] [blame] | 244 | } else if (max < 0) { // "tail" mode: keep the last N |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 245 | int len; |
| 246 | boolean rolled = false; |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 247 | byte[] last = null; |
| 248 | byte[] data = null; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 249 | do { |
| 250 | if (last != null) rolled = true; |
| 251 | byte[] tmp = last; last = data; data = tmp; |
| 252 | if (data == null) data = new byte[-max]; |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 253 | len = bis.read(data); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 254 | } while (len == data.length); |
| 255 | |
| 256 | if (last == null && len <= 0) return ""; |
| 257 | if (last == null) return new String(data, 0, len); |
| 258 | if (len > 0) { |
| 259 | rolled = true; |
| 260 | System.arraycopy(last, len, last, 0, last.length - len); |
| 261 | System.arraycopy(data, 0, last, last.length - len, len); |
| 262 | } |
| 263 | if (ellipsis == null || !rolled) return new String(last); |
| 264 | return ellipsis + new String(last); |
Dan Egnor | 42471dd | 2010-01-07 17:25:22 -0800 | [diff] [blame] | 265 | } else { // "cat" mode: size unknown, read it all in streaming fashion |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 266 | ByteArrayOutputStream contents = new ByteArrayOutputStream(); |
| 267 | int len; |
| 268 | byte[] data = new byte[1024]; |
| 269 | do { |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 270 | len = bis.read(data); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 271 | if (len > 0) contents.write(data, 0, len); |
| 272 | } while (len == data.length); |
| 273 | return contents.toString(); |
| 274 | } |
| 275 | } finally { |
Guang Zhu | 9061981 | 2012-10-12 15:50:44 -0700 | [diff] [blame] | 276 | bis.close(); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 277 | input.close(); |
| 278 | } |
| 279 | } |
Mike Lockwood | da8bb74 | 2011-05-28 13:24:04 -0400 | [diff] [blame] | 280 | |
| 281 | /** |
| 282 | * Writes string to file. Basically same as "echo -n $string > $filename" |
| 283 | * |
| 284 | * @param filename |
| 285 | * @param string |
| 286 | * @throws IOException |
| 287 | */ |
| 288 | public static void stringToFile(String filename, String string) throws IOException { |
| 289 | FileWriter out = new FileWriter(filename); |
| 290 | try { |
| 291 | out.write(string); |
| 292 | } finally { |
| 293 | out.close(); |
| 294 | } |
| 295 | } |
Wink Saville | 1b9a6a6 | 2011-06-04 07:31:35 -0700 | [diff] [blame] | 296 | |
Wink Saville | 6d25a99 | 2011-06-03 17:03:51 -0700 | [diff] [blame] | 297 | /** |
| 298 | * Computes the checksum of a file using the CRC32 checksum routine. |
| 299 | * The value of the checksum is returned. |
| 300 | * |
| 301 | * @param file the file to checksum, must not be null |
| 302 | * @return the checksum value or an exception is thrown. |
| 303 | */ |
| 304 | public static long checksumCrc32(File file) throws FileNotFoundException, IOException { |
| 305 | CRC32 checkSummer = new CRC32(); |
| 306 | CheckedInputStream cis = null; |
| 307 | |
| 308 | try { |
| 309 | cis = new CheckedInputStream( new FileInputStream(file), checkSummer); |
| 310 | byte[] buf = new byte[128]; |
| 311 | while(cis.read(buf) >= 0) { |
| 312 | // Just read for checksum to get calculated. |
| 313 | } |
| 314 | return checkSummer.getValue(); |
| 315 | } finally { |
| 316 | if (cis != null) { |
| 317 | try { |
| 318 | cis.close(); |
| 319 | } catch (IOException e) { |
| 320 | } |
| 321 | } |
| 322 | } |
| 323 | } |
Jeff Sharkey | d952690 | 2013-03-14 14:11:57 -0700 | [diff] [blame] | 324 | |
| 325 | /** |
| 326 | * Delete older files in a directory until only those matching the given |
| 327 | * constraints remain. |
| 328 | * |
| 329 | * @param minCount Always keep at least this many files. |
| 330 | * @param minAge Always keep files younger than this age. |
| 331 | */ |
| 332 | public static void deleteOlderFiles(File dir, int minCount, long minAge) { |
| 333 | if (minCount < 0 || minAge < 0) { |
| 334 | throw new IllegalArgumentException("Constraints must be positive or 0"); |
| 335 | } |
| 336 | |
| 337 | final File[] files = dir.listFiles(); |
| 338 | if (files == null) return; |
| 339 | |
| 340 | // Sort with newest files first |
| 341 | Arrays.sort(files, new Comparator<File>() { |
| 342 | @Override |
| 343 | public int compare(File lhs, File rhs) { |
| 344 | return (int) (rhs.lastModified() - lhs.lastModified()); |
| 345 | } |
| 346 | }); |
| 347 | |
| 348 | // Keep at least minCount files |
| 349 | for (int i = minCount; i < files.length; i++) { |
| 350 | final File file = files[i]; |
| 351 | |
| 352 | // Keep files newer than minAge |
| 353 | final long age = System.currentTimeMillis() - file.lastModified(); |
| 354 | if (age > minAge) { |
| 355 | Log.d(TAG, "Deleting old file " + file); |
| 356 | file.delete(); |
| 357 | } |
| 358 | } |
| 359 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 360 | } |