| /* |
| * 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 static android.system.OsConstants.SPLICE_F_MORE; |
| import static android.system.OsConstants.SPLICE_F_MOVE; |
| import static android.system.OsConstants.S_ISFIFO; |
| import static android.system.OsConstants.S_ISREG; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.provider.DocumentsContract.Document; |
| import android.system.ErrnoException; |
| import android.system.Os; |
| import android.system.StructStat; |
| import android.text.TextUtils; |
| import android.util.Log; |
| import android.util.Slog; |
| import android.webkit.MimeTypeMap; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| |
| import libcore.io.IoUtils; |
| import libcore.util.EmptyArray; |
| |
| import java.io.BufferedInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.File; |
| import java.io.FileDescriptor; |
| import java.io.FileInputStream; |
| import java.io.FileNotFoundException; |
| import java.io.FileOutputStream; |
| import java.io.FilenameFilter; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.nio.charset.StandardCharsets; |
| import java.util.Arrays; |
| import java.util.Comparator; |
| import java.util.Objects; |
| import java.util.concurrent.TimeUnit; |
| import java.util.regex.Pattern; |
| import java.util.zip.CRC32; |
| import java.util.zip.CheckedInputStream; |
| |
| /** |
| * Tools for managing files. Not for public consumption. |
| * @hide |
| */ |
| public class FileUtils { |
| private static final String TAG = "FileUtils"; |
| |
| public static final int S_IRWXU = 00700; |
| public static final int S_IRUSR = 00400; |
| public static final int S_IWUSR = 00200; |
| public static final int S_IXUSR = 00100; |
| |
| public static final int S_IRWXG = 00070; |
| public static final int S_IRGRP = 00040; |
| public static final int S_IWGRP = 00020; |
| public static final int S_IXGRP = 00010; |
| |
| public static final int S_IRWXO = 00007; |
| public static final int S_IROTH = 00004; |
| public static final int S_IWOTH = 00002; |
| public static final int S_IXOTH = 00001; |
| |
| /** Regular expression for safe filenames: no spaces or metacharacters. |
| * |
| * Use a preload holder so that FileUtils can be compile-time initialized. |
| */ |
| private static class NoImagePreloadHolder { |
| public static final Pattern SAFE_FILENAME_PATTERN = Pattern.compile("[\\w%+,./=_-]+"); |
| } |
| |
| private static final File[] EMPTY = new File[0]; |
| |
| private static final boolean ENABLE_COPY_OPTIMIZATIONS = true; |
| |
| private static final long COPY_CHECKPOINT_BYTES = 524288; |
| |
| public interface CopyListener { |
| public void onProgress(long progress); |
| } |
| |
| /** |
| * Set owner and mode of of given {@link File}. |
| * |
| * @param mode to apply through {@code chmod} |
| * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| * @return 0 on success, otherwise errno. |
| */ |
| public static int setPermissions(File path, int mode, int uid, int gid) { |
| return setPermissions(path.getAbsolutePath(), mode, uid, gid); |
| } |
| |
| /** |
| * Set owner and mode of of given path. |
| * |
| * @param mode to apply through {@code chmod} |
| * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| * @return 0 on success, otherwise errno. |
| */ |
| public static int setPermissions(String path, int mode, int uid, int gid) { |
| try { |
| Os.chmod(path, mode); |
| } catch (ErrnoException e) { |
| Slog.w(TAG, "Failed to chmod(" + path + "): " + e); |
| return e.errno; |
| } |
| |
| if (uid >= 0 || gid >= 0) { |
| try { |
| Os.chown(path, uid, gid); |
| } catch (ErrnoException e) { |
| Slog.w(TAG, "Failed to chown(" + path + "): " + e); |
| return e.errno; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Set owner and mode of of given {@link FileDescriptor}. |
| * |
| * @param mode to apply through {@code chmod} |
| * @param uid to apply through {@code chown}, or -1 to leave unchanged |
| * @param gid to apply through {@code chown}, or -1 to leave unchanged |
| * @return 0 on success, otherwise errno. |
| */ |
| public static int setPermissions(FileDescriptor fd, int mode, int uid, int gid) { |
| try { |
| Os.fchmod(fd, mode); |
| } catch (ErrnoException e) { |
| Slog.w(TAG, "Failed to fchmod(): " + e); |
| return e.errno; |
| } |
| |
| if (uid >= 0 || gid >= 0) { |
| try { |
| Os.fchown(fd, uid, gid); |
| } catch (ErrnoException e) { |
| Slog.w(TAG, "Failed to fchown(): " + e); |
| return e.errno; |
| } |
| } |
| |
| return 0; |
| } |
| |
| public static void copyPermissions(File from, File to) throws IOException { |
| try { |
| final StructStat stat = Os.stat(from.getAbsolutePath()); |
| Os.chmod(to.getAbsolutePath(), stat.st_mode); |
| Os.chown(to.getAbsolutePath(), stat.st_uid, stat.st_gid); |
| } catch (ErrnoException e) { |
| throw e.rethrowAsIOException(); |
| } |
| } |
| |
| /** |
| * Return owning UID of given path, otherwise -1. |
| */ |
| public static int getUid(String path) { |
| try { |
| return Os.stat(path).st_uid; |
| } catch (ErrnoException e) { |
| return -1; |
| } |
| } |
| |
| /** |
| * Perform an fsync on the given FileOutputStream. The stream at this |
| * point must be flushed but not yet closed. |
| */ |
| public static boolean sync(FileOutputStream stream) { |
| try { |
| if (stream != null) { |
| stream.getFD().sync(); |
| } |
| return true; |
| } catch (IOException e) { |
| } |
| return false; |
| } |
| |
| /** |
| * @deprecated use {@link #copy(InputStream, OutputStream)} instead. |
| */ |
| @Deprecated |
| public static boolean copyFile(File srcFile, File destFile) { |
| try { |
| copyFileOrThrow(srcFile, destFile); |
| return true; |
| } catch (IOException e) { |
| return false; |
| } |
| } |
| |
| /** |
| * @deprecated use {@link #copy(InputStream, OutputStream)} instead. |
| */ |
| @Deprecated |
| public static void copyFileOrThrow(File srcFile, File destFile) throws IOException { |
| try (InputStream in = new FileInputStream(srcFile)) { |
| copyToFileOrThrow(in, destFile); |
| } |
| } |
| |
| /** |
| * @deprecated use {@link #copy(InputStream, OutputStream)} instead. |
| */ |
| @Deprecated |
| public static boolean copyToFile(InputStream inputStream, File destFile) { |
| try { |
| copyToFileOrThrow(inputStream, destFile); |
| return true; |
| } catch (IOException e) { |
| return false; |
| } |
| } |
| |
| /** |
| * @deprecated use {@link #copy(InputStream, OutputStream)} instead. |
| */ |
| @Deprecated |
| public static void copyToFileOrThrow(InputStream in, File destFile) throws IOException { |
| if (destFile.exists()) { |
| destFile.delete(); |
| } |
| try (FileOutputStream out = new FileOutputStream(destFile)) { |
| copy(in, out); |
| try { |
| Os.fsync(out.getFD()); |
| } catch (ErrnoException e) { |
| throw e.rethrowAsIOException(); |
| } |
| } |
| } |
| |
| public static void copy(File from, File to) throws IOException { |
| try (FileInputStream in = new FileInputStream(from); |
| FileOutputStream out = new FileOutputStream(to)) { |
| copy(in, out); |
| } |
| } |
| |
| public static void copy(InputStream in, OutputStream out) throws IOException { |
| copy(in, out, null, null); |
| } |
| |
| public static void copy(InputStream in, OutputStream out, CopyListener listener, |
| CancellationSignal signal) throws IOException { |
| if (ENABLE_COPY_OPTIMIZATIONS) { |
| if (in instanceof FileInputStream && out instanceof FileOutputStream) { |
| copy(((FileInputStream) in).getFD(), ((FileOutputStream) out).getFD(), |
| listener, signal); |
| } |
| } |
| |
| // Worse case fallback to userspace |
| copyInternalUserspace(in, out, listener, signal); |
| } |
| |
| public static void copy(FileDescriptor in, FileDescriptor out) throws IOException { |
| copy(in, out, null, null); |
| } |
| |
| public static void copy(FileDescriptor in, FileDescriptor out, CopyListener listener, |
| CancellationSignal signal) throws IOException { |
| if (ENABLE_COPY_OPTIMIZATIONS) { |
| try { |
| final StructStat st_in = Os.fstat(in); |
| final StructStat st_out = Os.fstat(out); |
| if (S_ISREG(st_in.st_mode) && S_ISREG(st_out.st_mode)) { |
| copyInternalSendfile(in, out, listener, signal); |
| } else if (S_ISFIFO(st_in.st_mode) || S_ISFIFO(st_out.st_mode)) { |
| copyInternalSplice(in, out, listener, signal); |
| } |
| } catch (ErrnoException e) { |
| throw e.rethrowAsIOException(); |
| } |
| } |
| |
| // Worse case fallback to userspace |
| copyInternalUserspace(in, out, listener, signal); |
| } |
| |
| /** |
| * Requires one of input or output to be a pipe. |
| */ |
| @VisibleForTesting |
| public static void copyInternalSplice(FileDescriptor in, FileDescriptor out, |
| CopyListener listener, CancellationSignal signal) throws ErrnoException { |
| long progress = 0; |
| long checkpoint = 0; |
| |
| long t; |
| while ((t = Os.splice(in, null, out, null, COPY_CHECKPOINT_BYTES, |
| SPLICE_F_MOVE | SPLICE_F_MORE)) != 0) { |
| progress += t; |
| checkpoint += t; |
| |
| if (checkpoint >= COPY_CHECKPOINT_BYTES) { |
| if (signal != null) { |
| signal.throwIfCanceled(); |
| } |
| if (listener != null) { |
| listener.onProgress(progress); |
| } |
| checkpoint = 0; |
| } |
| } |
| } |
| |
| /** |
| * Requires both input and output to be a regular file. |
| */ |
| @VisibleForTesting |
| public static void copyInternalSendfile(FileDescriptor in, FileDescriptor out, |
| CopyListener listener, CancellationSignal signal) throws ErrnoException { |
| long progress = 0; |
| long checkpoint = 0; |
| |
| long t; |
| while ((t = Os.sendfile(out, in, null, COPY_CHECKPOINT_BYTES)) != 0) { |
| progress += t; |
| checkpoint += t; |
| |
| if (checkpoint >= COPY_CHECKPOINT_BYTES) { |
| if (signal != null) { |
| signal.throwIfCanceled(); |
| } |
| if (listener != null) { |
| listener.onProgress(progress); |
| } |
| checkpoint = 0; |
| } |
| } |
| } |
| |
| @VisibleForTesting |
| public static void copyInternalUserspace(FileDescriptor in, FileDescriptor out, |
| CopyListener listener, CancellationSignal signal) throws IOException { |
| copyInternalUserspace(new FileInputStream(in), new FileOutputStream(out), listener, signal); |
| } |
| |
| @VisibleForTesting |
| public static void copyInternalUserspace(InputStream in, OutputStream out, |
| CopyListener listener, CancellationSignal signal) throws IOException { |
| long progress = 0; |
| long checkpoint = 0; |
| byte[] buffer = new byte[8192]; |
| |
| int t; |
| while ((t = in.read(buffer)) != -1) { |
| out.write(buffer, 0, t); |
| |
| progress += t; |
| checkpoint += t; |
| |
| if (checkpoint >= COPY_CHECKPOINT_BYTES) { |
| if (signal != null) { |
| signal.throwIfCanceled(); |
| } |
| if (listener != null) { |
| listener.onProgress(progress); |
| } |
| checkpoint = 0; |
| } |
| } |
| } |
| |
| /** |
| * Check if a filename is "safe" (no metacharacters or spaces). |
| * @param file The file to check |
| */ |
| public static boolean isFilenameSafe(File file) { |
| // Note, we check whether it matches what's known to be safe, |
| // rather than what's known to be unsafe. Non-ASCII, control |
| // characters, etc. are all unsafe by default. |
| return NoImagePreloadHolder.SAFE_FILENAME_PATTERN.matcher(file.getPath()).matches(); |
| } |
| |
| /** |
| * Read a text file into a String, optionally limiting the length. |
| * @param file to read (will not seek, so things like /proc files are OK) |
| * @param max length (positive for head, negative of tail, 0 for no limit) |
| * @param ellipsis to add of the file was truncated (can be null) |
| * @return the contents of the file, possibly truncated |
| * @throws IOException if something goes wrong reading the file |
| */ |
| public static String readTextFile(File file, int max, String ellipsis) throws IOException { |
| InputStream input = new FileInputStream(file); |
| // wrapping a BufferedInputStream around it because when reading /proc with unbuffered |
| // input stream, bytes read not equal to buffer size is not necessarily the correct |
| // indication for EOF; but it is true for BufferedInputStream due to its implementation. |
| BufferedInputStream bis = new BufferedInputStream(input); |
| try { |
| long size = file.length(); |
| if (max > 0 || (size > 0 && max == 0)) { // "head" mode: read the first N bytes |
| if (size > 0 && (max == 0 || size < max)) max = (int) size; |
| byte[] data = new byte[max + 1]; |
| int length = bis.read(data); |
| if (length <= 0) return ""; |
| if (length <= max) return new String(data, 0, length); |
| if (ellipsis == null) return new String(data, 0, max); |
| return new String(data, 0, max) + ellipsis; |
| } else if (max < 0) { // "tail" mode: keep the last N |
| int len; |
| boolean rolled = false; |
| byte[] last = null; |
| byte[] data = null; |
| do { |
| if (last != null) rolled = true; |
| byte[] tmp = last; last = data; data = tmp; |
| if (data == null) data = new byte[-max]; |
| len = bis.read(data); |
| } while (len == data.length); |
| |
| if (last == null && len <= 0) return ""; |
| if (last == null) return new String(data, 0, len); |
| if (len > 0) { |
| rolled = true; |
| System.arraycopy(last, len, last, 0, last.length - len); |
| System.arraycopy(data, 0, last, last.length - len, len); |
| } |
| if (ellipsis == null || !rolled) return new String(last); |
| return ellipsis + new String(last); |
| } else { // "cat" mode: size unknown, read it all in streaming fashion |
| ByteArrayOutputStream contents = new ByteArrayOutputStream(); |
| int len; |
| byte[] data = new byte[1024]; |
| do { |
| len = bis.read(data); |
| if (len > 0) contents.write(data, 0, len); |
| } while (len == data.length); |
| return contents.toString(); |
| } |
| } finally { |
| bis.close(); |
| input.close(); |
| } |
| } |
| |
| public static void stringToFile(File file, String string) throws IOException { |
| stringToFile(file.getAbsolutePath(), string); |
| } |
| |
| /* |
| * Writes the bytes given in {@code content} to the file whose absolute path |
| * is {@code filename}. |
| */ |
| public static void bytesToFile(String filename, byte[] content) throws IOException { |
| if (filename.startsWith("/proc/")) { |
| final int oldMask = StrictMode.allowThreadDiskWritesMask(); |
| try (FileOutputStream fos = new FileOutputStream(filename)) { |
| fos.write(content); |
| } finally { |
| StrictMode.setThreadPolicyMask(oldMask); |
| } |
| } else { |
| try (FileOutputStream fos = new FileOutputStream(filename)) { |
| fos.write(content); |
| } |
| } |
| } |
| |
| /** |
| * Writes string to file. Basically same as "echo -n $string > $filename" |
| * |
| * @param filename |
| * @param string |
| * @throws IOException |
| */ |
| public static void stringToFile(String filename, String string) throws IOException { |
| bytesToFile(filename, string.getBytes(StandardCharsets.UTF_8)); |
| } |
| |
| /** |
| * Computes the checksum of a file using the CRC32 checksum routine. |
| * The value of the checksum is returned. |
| * |
| * @param file the file to checksum, must not be null |
| * @return the checksum value or an exception is thrown. |
| */ |
| public static long checksumCrc32(File file) throws FileNotFoundException, IOException { |
| CRC32 checkSummer = new CRC32(); |
| CheckedInputStream cis = null; |
| |
| try { |
| cis = new CheckedInputStream( new FileInputStream(file), checkSummer); |
| byte[] buf = new byte[128]; |
| while(cis.read(buf) >= 0) { |
| // Just read for checksum to get calculated. |
| } |
| return checkSummer.getValue(); |
| } finally { |
| if (cis != null) { |
| try { |
| cis.close(); |
| } catch (IOException e) { |
| } |
| } |
| } |
| } |
| |
| /** |
| * Delete older files in a directory until only those matching the given |
| * constraints remain. |
| * |
| * @param minCount Always keep at least this many files. |
| * @param minAgeMs Always keep files younger than this age, in milliseconds. |
| * @return if any files were deleted. |
| */ |
| public static boolean deleteOlderFiles(File dir, int minCount, long minAgeMs) { |
| if (minCount < 0 || minAgeMs < 0) { |
| throw new IllegalArgumentException("Constraints must be positive or 0"); |
| } |
| |
| final File[] files = dir.listFiles(); |
| if (files == null) return false; |
| |
| // Sort with newest files first |
| Arrays.sort(files, new Comparator<File>() { |
| @Override |
| public int compare(File lhs, File rhs) { |
| return Long.compare(rhs.lastModified(), lhs.lastModified()); |
| } |
| }); |
| |
| // Keep at least minCount files |
| boolean deleted = false; |
| for (int i = minCount; i < files.length; i++) { |
| final File file = files[i]; |
| |
| // Keep files newer than minAgeMs |
| final long age = System.currentTimeMillis() - file.lastModified(); |
| if (age > minAgeMs) { |
| if (file.delete()) { |
| Log.d(TAG, "Deleted old file " + file); |
| deleted = true; |
| } |
| } |
| } |
| return deleted; |
| } |
| |
| /** |
| * Test if a file lives under the given directory, either as a direct child |
| * or a distant grandchild. |
| * <p> |
| * Both files <em>must</em> have been resolved using |
| * {@link File#getCanonicalFile()} to avoid symlink or path traversal |
| * attacks. |
| */ |
| public static boolean contains(File[] dirs, File file) { |
| for (File dir : dirs) { |
| if (contains(dir, file)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Test if a file lives under the given directory, either as a direct child |
| * or a distant grandchild. |
| * <p> |
| * Both files <em>must</em> have been resolved using |
| * {@link File#getCanonicalFile()} to avoid symlink or path traversal |
| * attacks. |
| */ |
| public static boolean contains(File dir, File file) { |
| if (dir == null || file == null) return false; |
| return contains(dir.getAbsolutePath(), file.getAbsolutePath()); |
| } |
| |
| public static boolean contains(String dirPath, String filePath) { |
| if (dirPath.equals(filePath)) { |
| return true; |
| } |
| if (!dirPath.endsWith("/")) { |
| dirPath += "/"; |
| } |
| return filePath.startsWith(dirPath); |
| } |
| |
| public static boolean deleteContentsAndDir(File dir) { |
| if (deleteContents(dir)) { |
| return dir.delete(); |
| } else { |
| return false; |
| } |
| } |
| |
| public static boolean deleteContents(File dir) { |
| File[] files = dir.listFiles(); |
| boolean success = true; |
| if (files != null) { |
| for (File file : files) { |
| if (file.isDirectory()) { |
| success &= deleteContents(file); |
| } |
| if (!file.delete()) { |
| Log.w(TAG, "Failed to delete " + file); |
| success = false; |
| } |
| } |
| } |
| return success; |
| } |
| |
| private static boolean isValidExtFilenameChar(char c) { |
| switch (c) { |
| case '\0': |
| case '/': |
| return false; |
| default: |
| return true; |
| } |
| } |
| |
| /** |
| * Check if given filename is valid for an ext4 filesystem. |
| */ |
| public static boolean isValidExtFilename(String name) { |
| return (name != null) && name.equals(buildValidExtFilename(name)); |
| } |
| |
| /** |
| * Mutate the given filename to make it valid for an ext4 filesystem, |
| * replacing any invalid characters with "_". |
| */ |
| public static String buildValidExtFilename(String name) { |
| if (TextUtils.isEmpty(name) || ".".equals(name) || "..".equals(name)) { |
| return "(invalid)"; |
| } |
| final StringBuilder res = new StringBuilder(name.length()); |
| for (int i = 0; i < name.length(); i++) { |
| final char c = name.charAt(i); |
| if (isValidExtFilenameChar(c)) { |
| res.append(c); |
| } else { |
| res.append('_'); |
| } |
| } |
| trimFilename(res, 255); |
| return res.toString(); |
| } |
| |
| private static boolean isValidFatFilenameChar(char c) { |
| if ((0x00 <= c && c <= 0x1f)) { |
| return false; |
| } |
| switch (c) { |
| case '"': |
| case '*': |
| case '/': |
| case ':': |
| case '<': |
| case '>': |
| case '?': |
| case '\\': |
| case '|': |
| case 0x7F: |
| return false; |
| default: |
| return true; |
| } |
| } |
| |
| /** |
| * Check if given filename is valid for a FAT filesystem. |
| */ |
| public static boolean isValidFatFilename(String name) { |
| return (name != null) && name.equals(buildValidFatFilename(name)); |
| } |
| |
| /** |
| * Mutate the given filename to make it valid for a FAT filesystem, |
| * replacing any invalid characters with "_". |
| */ |
| public static String buildValidFatFilename(String name) { |
| if (TextUtils.isEmpty(name) || ".".equals(name) || "..".equals(name)) { |
| return "(invalid)"; |
| } |
| final StringBuilder res = new StringBuilder(name.length()); |
| for (int i = 0; i < name.length(); i++) { |
| final char c = name.charAt(i); |
| if (isValidFatFilenameChar(c)) { |
| res.append(c); |
| } else { |
| res.append('_'); |
| } |
| } |
| // Even though vfat allows 255 UCS-2 chars, we might eventually write to |
| // ext4 through a FUSE layer, so use that limit. |
| trimFilename(res, 255); |
| return res.toString(); |
| } |
| |
| @VisibleForTesting |
| public static String trimFilename(String str, int maxBytes) { |
| final StringBuilder res = new StringBuilder(str); |
| trimFilename(res, maxBytes); |
| return res.toString(); |
| } |
| |
| private static void trimFilename(StringBuilder res, int maxBytes) { |
| byte[] raw = res.toString().getBytes(StandardCharsets.UTF_8); |
| if (raw.length > maxBytes) { |
| maxBytes -= 3; |
| while (raw.length > maxBytes) { |
| res.deleteCharAt(res.length() / 2); |
| raw = res.toString().getBytes(StandardCharsets.UTF_8); |
| } |
| res.insert(res.length() / 2, "..."); |
| } |
| } |
| |
| public static String rewriteAfterRename(File beforeDir, File afterDir, String path) { |
| if (path == null) return null; |
| final File result = rewriteAfterRename(beforeDir, afterDir, new File(path)); |
| return (result != null) ? result.getAbsolutePath() : null; |
| } |
| |
| public static String[] rewriteAfterRename(File beforeDir, File afterDir, String[] paths) { |
| if (paths == null) return null; |
| final String[] result = new String[paths.length]; |
| for (int i = 0; i < paths.length; i++) { |
| result[i] = rewriteAfterRename(beforeDir, afterDir, paths[i]); |
| } |
| return result; |
| } |
| |
| /** |
| * Given a path under the "before" directory, rewrite it to live under the |
| * "after" directory. For example, {@code /before/foo/bar.txt} would become |
| * {@code /after/foo/bar.txt}. |
| */ |
| public static File rewriteAfterRename(File beforeDir, File afterDir, File file) { |
| if (file == null || beforeDir == null || afterDir == null) return null; |
| if (contains(beforeDir, file)) { |
| final String splice = file.getAbsolutePath().substring( |
| beforeDir.getAbsolutePath().length()); |
| return new File(afterDir, splice); |
| } |
| return null; |
| } |
| |
| private static File buildUniqueFileWithExtension(File parent, String name, String ext) |
| throws FileNotFoundException { |
| File file = buildFile(parent, name, ext); |
| |
| // If conflicting file, try adding counter suffix |
| int n = 0; |
| while (file.exists()) { |
| if (n++ >= 32) { |
| throw new FileNotFoundException("Failed to create unique file"); |
| } |
| file = buildFile(parent, name + " (" + n + ")", ext); |
| } |
| |
| return file; |
| } |
| |
| /** |
| * Generates a unique file name under the given parent directory. If the display name doesn't |
| * have an extension that matches the requested MIME type, the default extension for that MIME |
| * type is appended. If a file already exists, the name is appended with a numerical value to |
| * make it unique. |
| * |
| * For example, the display name 'example' with 'text/plain' MIME might produce |
| * 'example.txt' or 'example (1).txt', etc. |
| * |
| * @throws FileNotFoundException |
| */ |
| public static File buildUniqueFile(File parent, String mimeType, String displayName) |
| throws FileNotFoundException { |
| final String[] parts = splitFileName(mimeType, displayName); |
| return buildUniqueFileWithExtension(parent, parts[0], parts[1]); |
| } |
| |
| /** |
| * Generates a unique file name under the given parent directory, keeping |
| * any extension intact. |
| */ |
| public static File buildUniqueFile(File parent, String displayName) |
| throws FileNotFoundException { |
| final String name; |
| final String ext; |
| |
| // Extract requested extension from display name |
| final int lastDot = displayName.lastIndexOf('.'); |
| if (lastDot >= 0) { |
| name = displayName.substring(0, lastDot); |
| ext = displayName.substring(lastDot + 1); |
| } else { |
| name = displayName; |
| ext = null; |
| } |
| |
| return buildUniqueFileWithExtension(parent, name, ext); |
| } |
| |
| /** |
| * Splits file name into base name and extension. |
| * If the display name doesn't have an extension that matches the requested MIME type, the |
| * extension is regarded as a part of filename and default extension for that MIME type is |
| * appended. |
| */ |
| public static String[] splitFileName(String mimeType, String displayName) { |
| String name; |
| String ext; |
| |
| if (Document.MIME_TYPE_DIR.equals(mimeType)) { |
| name = displayName; |
| ext = null; |
| } else { |
| String mimeTypeFromExt; |
| |
| // Extract requested extension from display name |
| final int lastDot = displayName.lastIndexOf('.'); |
| if (lastDot >= 0) { |
| name = displayName.substring(0, lastDot); |
| ext = displayName.substring(lastDot + 1); |
| mimeTypeFromExt = MimeTypeMap.getSingleton().getMimeTypeFromExtension( |
| ext.toLowerCase()); |
| } else { |
| name = displayName; |
| ext = null; |
| mimeTypeFromExt = null; |
| } |
| |
| if (mimeTypeFromExt == null) { |
| mimeTypeFromExt = "application/octet-stream"; |
| } |
| |
| final String extFromMimeType = MimeTypeMap.getSingleton().getExtensionFromMimeType( |
| mimeType); |
| if (Objects.equals(mimeType, mimeTypeFromExt) || Objects.equals(ext, extFromMimeType)) { |
| // Extension maps back to requested MIME type; allow it |
| } else { |
| // No match; insist that create file matches requested MIME |
| name = displayName; |
| ext = extFromMimeType; |
| } |
| } |
| |
| if (ext == null) { |
| ext = ""; |
| } |
| |
| return new String[] { name, ext }; |
| } |
| |
| private static File buildFile(File parent, String name, String ext) { |
| if (TextUtils.isEmpty(ext)) { |
| return new File(parent, name); |
| } else { |
| return new File(parent, name + "." + ext); |
| } |
| } |
| |
| public static @NonNull String[] listOrEmpty(@Nullable File dir) { |
| if (dir == null) return EmptyArray.STRING; |
| final String[] res = dir.list(); |
| if (res != null) { |
| return res; |
| } else { |
| return EmptyArray.STRING; |
| } |
| } |
| |
| public static @NonNull File[] listFilesOrEmpty(@Nullable File dir) { |
| if (dir == null) return EMPTY; |
| final File[] res = dir.listFiles(); |
| if (res != null) { |
| return res; |
| } else { |
| return EMPTY; |
| } |
| } |
| |
| public static @NonNull File[] listFilesOrEmpty(@Nullable File dir, FilenameFilter filter) { |
| if (dir == null) return EMPTY; |
| final File[] res = dir.listFiles(filter); |
| if (res != null) { |
| return res; |
| } else { |
| return EMPTY; |
| } |
| } |
| |
| public static @Nullable File newFileOrNull(@Nullable String path) { |
| return (path != null) ? new File(path) : null; |
| } |
| |
| /** |
| * Creates a directory with name {@code name} under an existing directory {@code baseDir}. |
| * Returns a {@code File} object representing the directory on success, {@code null} on |
| * failure. |
| */ |
| public static @Nullable File createDir(File baseDir, String name) { |
| final File dir = new File(baseDir, name); |
| |
| if (dir.exists()) { |
| return dir.isDirectory() ? dir : null; |
| } |
| |
| return dir.mkdir() ? dir : null; |
| } |
| |
| /** |
| * Round the given size of a storage device to a nice round power-of-two |
| * value, such as 256MB or 32GB. This avoids showing weird values like |
| * "29.5GB" in UI. |
| */ |
| public static long roundStorageSize(long size) { |
| long val = 1; |
| long pow = 1; |
| while ((val * pow) < size) { |
| val <<= 1; |
| if (val > 512) { |
| val = 1; |
| pow *= 1000; |
| } |
| } |
| return val * pow; |
| } |
| |
| @VisibleForTesting |
| public static class MemoryPipe extends Thread implements AutoCloseable { |
| private final FileDescriptor[] pipe; |
| private final byte[] data; |
| private final boolean sink; |
| |
| private MemoryPipe(byte[] data, boolean sink) throws IOException { |
| try { |
| this.pipe = Os.pipe(); |
| } catch (ErrnoException e) { |
| throw e.rethrowAsIOException(); |
| } |
| this.data = data; |
| this.sink = sink; |
| } |
| |
| private MemoryPipe startInternal() { |
| super.start(); |
| return this; |
| } |
| |
| public static MemoryPipe createSource(byte[] data) throws IOException { |
| return new MemoryPipe(data, false).startInternal(); |
| } |
| |
| public static MemoryPipe createSink(byte[] data) throws IOException { |
| return new MemoryPipe(data, true).startInternal(); |
| } |
| |
| public FileDescriptor getFD() { |
| return sink ? pipe[1] : pipe[0]; |
| } |
| |
| public FileDescriptor getInternalFD() { |
| return sink ? pipe[0] : pipe[1]; |
| } |
| |
| @Override |
| public void run() { |
| final FileDescriptor fd = getInternalFD(); |
| try { |
| int i = 0; |
| while (i < data.length) { |
| if (sink) { |
| i += Os.read(fd, data, i, data.length - i); |
| } else { |
| i += Os.write(fd, data, i, data.length - i); |
| } |
| } |
| } catch (IOException | ErrnoException e) { |
| throw new RuntimeException(e); |
| } finally { |
| if (sink) { |
| SystemClock.sleep(TimeUnit.SECONDS.toMillis(1)); |
| } |
| IoUtils.closeQuietly(fd); |
| } |
| } |
| |
| @Override |
| public void close() throws Exception { |
| IoUtils.closeQuietly(getFD()); |
| } |
| } |
| } |